Computer Science & AI,News & Press - A Blog by Fausto Intilla (WWW.OLOSCIENCE.COM)

The Internet of Things: Toolbox to Help Objects Communicating Via the Net.

2011-06-18T07:48:00.000-07:00

ScienceDaily (June 17, 2011) — Increasingly, the things people use on a daily basis can be connected to the Internet. An alarm clock not only rings, but can also switch on the coffee machine while turning on the light. But what is needed to ensure that the Internet of Things operates as efficiently as possible? Thus far, the Internet has been an arena reserved for people. But now more and more physical objects are being connected to the Internet: we read emails on our mobile telephones, we have electricity meters that report readings automatically, and pulse monitors and running shoes that publish information about our daily jog directly on Facebook.
Tools for collaboration The Internet of Things will introduce new smart objects to our homes. One challenge is to find effective solutions to enable different products to work together. Currently no standardised tools or distribution platforms exist in this area.
A group of Norwegian researchers have been addressing this issue. In the research project Infrastructure for Integrated Services (ISIS) they have created a platform for developing and distributing applications for the Internet of Things. The platform encompasses a programming tool for developers, called Arctis and the website ISIS Store for downloading applications. The project has received funding from the Research Council of Norway's Large-scale Programme VERDIKT.
Simple programming
Arctis was developed by researchers at the Norwegian University of Science and Technology (NTNU). One of them is postdoctoral researcher Frank Alexander Kraemer.
"In a 'smart' everyday life objects and applications often need to be connected to several different communication services, sensors and other components. At the same time they need to respond quickly to changes and the actions of users. This requires very good control over concurrence in the system, which can be difficult to achieve with normal programming," he explains.
Dr Kraemer believes that the tool will make it easier to create new applications, adapt them to existing applications and update software as necessary.
"Developing a simple application with Arctis can be as easy as fitting together two building blocks, but more advanced applications can also be created, depending on what you are looking for," Dr Kraemer continues.
Talking to each other
"It is the collaborative system ICE Composition Engine (ICE) that will govern the whole thing and allow the objects to talk to each other," explains Reidar Martin Svendsen, project manager at the Norwegian telecommunications company the Telenor Group.
ICE can both manage the communication between objects in your home and keep track of any updates. The system is installed on a modem, a decoder or an adapter in the home and provides the user with a local gateway which ensures that the Internet of Things will continue to work even when the user is offline.
Key developers
Telenor is seeking to become an operator for the Internet of Things by acting as a link between developers and end-users. But if the company is to succeed, a sufficient number of developers will need to choose to use its tools.
"We have established our own App Store where talented developers can publish the new applications they create and end-users can buy and download the applications they need. Basically, you can choose software according to your own needs and preferences," says Mr Svendsen.
The downloaded applications can be combined as needed using a software programme called Puzzle. The Puzzle programme is a user interface to the ICE system.
Safe connections
For the project to flourish, people have to be willing to pay for the applications. There are already many similar applications available online free-of-charge through the data infrastructure platform Pachube, for example. Why are users going to pay for something they can download legally and at no cost?
"It is better if a well-known operator is responsible for critical systems such as house alarms. For these types of systems you should go via the App Store to a supplier you trust. You don't know anything about the intentions of those who put out programmes free-of-charge on the Internet. But if your system needs updating or you require a service, it is an advantage to be using a reputable, recognised operator," explains Mr Svendsen.
"On the whole it will be up to the developers to decide what to charge for. At the ISIS Store there are currently a number of applications available that can be downloaded free-of-charge," he continues.

Story Source:
The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by The Research Council of Norway. The original article was written by Geir Aas/Else Lie; translation by Anna Godson/Carol B. Eckmann.

Faster and More Efficient Software for the US Air Force.

2010-01-12T11:24:00.001-08:00

Source: ScienceDaily

------------------------

ScienceDaily (Jan. 12, 2010) — Researchers at the University of Nebraska in Lincoln have addressed the issue of faulty software by developing an algorithm and open source tool that is 300 times faster at generating tests and also reduces current software testing time.

The new algorithm has potential to increase the efficiency of the software testing process across systems.
The project, funded in part by an Air Force Office of Scientific Research (AFOSR) Young Investigator Award and through a National Science Foundation Early CAREER Award, is of particular interest to the military because of the potential to reduce errors in theater. This technology will also be helpful to the private sector where some agencies are reporting financial losses of up to 50 billion dollars per year because of poor software.
"Software failures have the potential to cause financial, environmental or bodily harm," said lead researcher, Dr. Myra Cohen. "Our techniques will help to improve the quality of software in the military to help ensure that those systems behave properly in the field."
"The ultimate goal of research like this is not just to reduce software testing costs, but to do so while maintaining or even increasing confidence in the tests themselves," said AFOSR Program Manager, Dr. David Luginbuhl who is overseeing Cohen's work.
"Although algorithms exist that can produce samples for testing, few can handle dependencies between features well. Either they run slowly or they select very large test schedules, which means that testing takes too long," said Cohen.
Her project, called "Just Enough Testing" aims to re-use test results across different systems that share similar sets of features so the time to test a single system is reduced.
Large and complex families of software systems are common, and within them, groups of interacting features may cause faults to occur. The scientists have examined ways to ensure that faults are found earlier and more often in these types of systems.
"In the long term, we expect that as software product lines are used to produce large numbers of systems, and as they mature over time, we will be able to deploy new systems faster and with less likelihood of failure," she said.

Story Source:
Adapted from materials provided by Air Force Office of Scientific Research.

'Wet' Computing Systems to Boost Processing Power.

2010-01-12T11:19:00.000-08:00

Source: ScienceDaily

---------------------------

ScienceDaily (Jan. 12, 2010) — A new kind of information processing technology inspired by chemical processes in living systems is being developed by researchers at the University of Southampton.

Dr Maurits de Planque and Dr Klaus-Peter Zauner at the University's School of Electronics and Computer Science (ECS) are working on a project which has just received €1.8 from the European Union's Future and Emerging Technologies (FET) Proactive Initiatives, which recognises ground-breaking work which has already demonstrated important potential.
The researchers, Dr de Planque, a biochemist, and Dr Zauner, a computer scientist, will adapt brain processes to a 'wet' information processing scenario by setting up chemicals in a tube which behave like the transistors in a computer chip
"What we are developing here is a very crude, minimal liquid brain and the final computer will be 'wet' just like our brain," said Dr Zauner. "People realise now that the best information processes we have are in our heads and as we are increasingly finding that silicon has its limitations in terms of information processing, we need to explore other approaches, which is exactly what we are doing here."
The project, entitled Artificial Wet Neuronal Networks from Compartmentalised Excitable Chemical Material, which is being co-ordinated by Friedrich Schiller University Jena with other project partners, the University of the West of England, Bristol and the Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, will run for three years and involves three complementary objectives.
The first is to engineer lipid-coated water droplets, inspired by biological cells, containing an excitable chemical medium and then to connect the droplets into networks in which they can communicate through chemical signals. The second objective is to design information-processing architectures based on the droplets and to demonstrate purposeful information processing in droplet architectures. The third objective is to establish and explore the potential and limitations of droplet architectures.
"Our system will copy some key features of neuronal pathways in the brain and will be capable of excitation, self-repair and self-assembly," said Dr de Planque.

Story Source:
Adapted from materials provided by University of Southampton, via AlphaGalileo.

New multi-touch screen technology developed (with Video)

2010-01-12T06:24:00.000-08:00

Source: Physorg.com

Scientists from New York University have formed a company to bring flexible multi-touch screens using a new technology to a range of devices, from e-readers to musical instruments. The new touch screens respond to all kinds of objects, as well as fingers and hands.

The team, led by Ken Perlin and Ilya Rosenberg from the Media Research Laboratory, formed their company Touchco to develop IFSR (interpolating force-sensitive resistance) technology, which uses resistors sensitive to the force or pressure applied to touch points. This, along with scanning technology and positional interpolation, allows for (theoretically) unlimited simultaneous touch inputs (in contrast to other touch technologies such as the capacitive touch screen used by iPhone, which can track limited touch points). It has low power requirements and is inexpensive, since Touchco expects to sell the screen material at $10 per square foot. The technology is easily scalable for use in small or large devices.

Perlin said that the IFSR technology is likely to appear in a new range of e-readers later this year, and will also be used in laptops or notebooks, and new types of musical instruments. In computer applications the touch pads allow the user to control the cursor with a light touch, but to select and manipulate objects when more pressure is applied.
The company has also been collaborating with Disney to develop a digital sketchbook that will use sensitive pressure sensors capable of differentiating between the touch of a hand, a pencil, brush or eraser. Drawing pictures is just one of many possible applications of the technology.

The touch pads consist of layers of FSR ink sandwiched between opaque or transparent sheets of plastic onto which conductive wires are printed. The total thickness is only 0.25 mm. When pressure is applied to an FSR sensor a current flows from the wires in one layer to the wires in the other layer, and the pressure applied is determined by the amount of electric current flowing from layer to layer. Arranging sensors in a grid would have been expensive and impractical, so Touchco developed scanners to measure the touches and determine their positions. Resolution is 254 µm (100 dpi), but this can be increased by decreasing the wire spacing.
Touchco has already begun selling developer kits to device manufacturers and expects to see IFSR technology finding many applications during 2010.

More information: Touchco: http://touchco.com/

Stanford Univesity: We're emulating the brain ...in silicon!

2010-01-12T04:32:00.001-08:00

Source: Stanford University/Bioengineering Department

Welcome to Brains in Silicon. Learn about the lab, get to know the brains that work here, and find out about new projects that you could join. We have crafted two complementary objectives: To use existing knowledge of brain function in designing an affordable supercomputer—one that can itself serve as a tool to investigate brain function—feeding back and contributing to a fundamental, biological understanding of how the brain works.We model brains using an approach far more efficient than software simulation: We emulate the flow of ions directly with the flow of electrons—don't worry, on the outside it looks just like software.Welcome and enjoy your time here!

Statistics Page

2010-01-11T13:40:00.000-08:00

map counter

blog counter

flag counter

First Intelligent Financial Search Engine Developed.

2009-10-01T11:12:00.001-07:00

SOURCE

ScienceDaily (Sep. 30, 2009) — Researchers from the Carlos III University of Madrid (UCM3) have completed the development of the first search engine designed to search for information from the financial and stock market sector based on semantic technology, which enables one to make more accurate thematic searches adapted to the needs of each user.

Unlike conventional search engines, SONAR -so named by its creators- enables the user to perform structured searches which are not based solely on concordance with a series of key words. This corporate financial search engine based on semantic technology, as described on the project website (http://www.proyecto-sonar.org), was developed by researchers from the UC3M in partnership with the University of Murcia, el Instituto de Empresa (the Business Institute) and the company Indra.
According to its creators, it has two main advantages. First, its effectiveness in a concrete domain- that of finance- which is closely defined and has very precise vocabulary. According to Juan Miguel Gómez Berbís, from the Computer Department of the UC3M “This verticality distinguishes SONAR from other more generic search engines, such as Google or Bing” Second, its capacity to establish relations between news, share valuations and prices via logical reasoning.
The first prototype works by making use of semantic web elements. Basically, the system collects data from both public information sources (Internet) and private, corporate ones (Intranet), adds them to a repository of semantically recorded data (labelled and structured) and allows intelligent access to this data. To achieve this, the platform incorporates an inference engine, a mechanism capable of performing reasoning tasks on the recorded information, as well as a natural language processor, which helps the user to perform the search in the simplest way possible. In this way the results obtained are matched to requests, eliminating ambiguities in polysemic terms, for example in searches carried out by users on stored data. “SONAR enables us to establish relations between different sources of information and discover and expand our knowledge, while at the same time it allows us to classify them so that users can get much more benefit from the experience”
Potential users
This search tool is designed for both private investors and large financial concerns. Its creators anticipate that it will be a very useful tool for analysts and stockbrokers. “It will be especially useful to the finance departments of banks and saving banks or to add to an existing search engine added value over its competitors” Gómez Berbís points out. And the search for accurate, reliable, relevant information in this business area has become a key factor in a domain where speed and quality of data are critical factors with an exceptional impact on business processes.
According to the researchers, this project aims to respond to a need from the financial sector, that is, the analysis of a large volume of information in order to take decisions. In this way, the execution of this project will allow the financial community to have access to a set of intelligent systems for the aggregated search of information in the financial domain and enable them to improve procedures for integrating company information and processes.
Researchers are currently incorporating new functions into the search tool and also receiving requests to adapt it to other domains, such as transport and biotechnology. In any case, the project is constantly evolving in order to enhance accuracy and reliability. “In SONAR2 we are working on two Intelligent Decision Support Systems for Financial Investments, one based on Fundamental Analysis and the other on Technical Chartist Analysis, which assists the work of the trader and average investor”, reveals professor Gómez Berbis.
Adapted from materials provided by Universidad Carlos III de Madrid.

Ants Vs. Worms: New Computer Security Mimics Nature.

2009-09-28T12:20:00.001-07:00

SOURCE

ScienceDaily (Sep. 28, 2009) — In the never-ending battle to protect computer networks from intruders, security experts are deploying a new defense modeled after one of nature’s hardiest creatures — the ant.

Unlike traditional security devices, which are static, these “digital ants” wander through computer networks looking for threats, such as “computer worms” — self-replicating programs designed to steal information or facilitate unauthorized use of machines. When a digital ant detects a threat, it doesn’t take long for an army of ants to converge at that location, drawing the attention of human operators who step in to investigate.
The concept, called “swarm intelligence,” promises to transform cyber security because it adapts readily to changing threats.
“In nature, we know that ants defend against threats very successfully,” explains Professor of Computer Science Errin Fulp, an expert in security and computer networks. “They can ramp up their defense rapidly, and then resume routine behavior quickly after an intruder has been stopped. We were trying to achieve that same framework in a computer system.”
Current security devices are designed to defend against all known threats at all times, but the bad guys who write malware — software created for malicious purposes — keep introducing slight variations to evade computer defenses.
As new variations are discovered and updates issued, security programs gobble more resources, antivirus scans take longer and machines run slower — a familiar problem for most computer users.
Glenn Fink, a research scientist at Pacific Northwest National Laboratory (PNNL) in Richland, Wash., came up with the idea of copying ant behavior. PNNL, one of 10 Department of Energy laboratories, conducts cutting-edge research in cyber security.
Fink was familiar with Fulp’s expertise developing faster scans using parallel processing — dividing computer data into batches like lines of shoppers going through grocery store checkouts, where each lane is focused on certain threats. He invited Fulp and Wake Forest graduate students Wes Featherstun and Brian Williams to join a project there this summer that tested digital ants on a network of 64 computers.
Swarm intelligence, the approach developed by PNNL and Wake Forest, divides up the process of searching for specific threats.
“Our idea is to deploy 3,000 different types of digital ants, each looking for evidence of a threat,” Fulp says. “As they move about the network, they leave digital trails modeled after the scent trails ants in nature use to guide other ants. Each time a digital ant identifies some evidence, it is programmed to leave behind a stronger scent. Stronger scent trails attract more ants, producing the swarm that marks a potential computer infection.”
In the study this summer, Fulp introduced a worm into the network, and the digital ants successfully found it. PNNL has extended the project this semester, and Featherstun and Williams plan to incorporate the research into their master’s theses.
Fulp says the new security approach is best suited for large networks that share many identical machines, such as those found in governments, large corporations and universities.
Computer users need not worry that a swarm of digital ants will decide to take up residence in their machine by mistake. Digital ants cannot survive without software “sentinels” located at each machine, which in turn report to network “sergeants” monitored by humans, who supervise the colony and maintain ultimate control.
Adapted from materials provided by Wake Forest University. Original article written by Eric Frazier, Office of Communications and External Relations.

Reconstruct Mars Automatically In Minutes.

2009-09-20T01:27:00.001-07:00

SOURCE

ScienceDaily (Sep. 18, 2009) — A computer system is under development that can automatically combine images of the Martian surface, captured by landers or rovers, in order to reproduce a three dimensional view of the red planet. The resulting model can be viewed from any angle, giving astronomers a realistic and immersive impression of the landscape.

The new development has been presented at the European Planetary Science Congress in Potsdam by Dr Michal Havlena.
“The feeling of ‘being right there’ will give scientists a much better understanding of the images. The only input we need are the captured raw images and the internal camera calibration. After minutes of computation on a standard PC, a three dimensional model of the captured scene is obtained,” said Dr Havlena.
The growing amount of available imagery from Mars is nearly impossible to handle for the manual image processing techniques used to date. The new automated method, which allows fast high quality image processing, was developed at the Center for Machine Perception of the Technical University of Prague, under the supervision of Tomas Pajdla, as a part of the EU FP7 Project PRoVisG.
From the technical point of view, the image processing consists of three stages: the first step is determining the image order. If the input images are unordered, i.e. they do not form a sequence but still are somehow connected, a state-of-the-art image indexing technique is able to find images of cameras observing the same part of the scene. To start with, up to a thousand features on each image are detected and “translated” into visual words, according to a visual vocabulary trained on images from Mars. Then, starting from an arbitrary image, the following image is selected if it shares the highest number of visual words with the previous image.
The second step of the pipeline, the so-called ‘structure-from-motion computation’, helps scientists determine the accurate camera positions and rotations in three dimensional space. Just five corresponding features are enough to obtain a relative camera pose between the two images that have been selected as sequential.
The last and most important step is the so-called ‘dense 3D model generation’ of the captured scene, which essentially creates and fuses the Martian surface depth maps. To do this, the model uses the disparities (parallaxes) present in images taken at two distinct camera positions, which were identified in the second step.
“The pipeline has already been used successfully to reconstruct a three dimensional model from nine images captured by the Phoenix Mars Lander, which were obtained just after performing some digging operation on the Mars surface,” said Dr Havlena.
“The challenge is now to reconstruct larger parts of the surface of the red planet, captured by the Mars Exploration Rovers Spirit and Opportunity,” concluded Dr Havlena.
Adapted from materials provided by Europlanet Media Centre, via AlphaGalileo.

Quantum Computing: From qubits to qudits, with five energy levels

2009-08-13T22:21:00.001-07:00

Source: ScienceDaily

ScienceDaily (Aug. 13, 2009) — Scientists at UC Santa Barbara have devised a new type of superconducting circuit that behaves quantum mechanically – but has up to five levels of energy instead of the usual two. The findings are published in the August 7 issue of Science.

These circuits act like artificial atoms in that they can only gain or lose energy in packets, or quanta, by jumping between discrete energy levels. "In our previous work, we focused on systems with just two energy levels, 'qubits,' because they are the quantum analog of 'bits,' which have two states, on and off," said Matthew Neeley, first author and a graduate student at UCSB.
He explained that in this work they operated a quantum circuit as a more complicated artificial atom with up to five energy levels. The generic term for such a system is "qudit," where 'd' refers to the number of energy levels –– in this case, 'd' equals five.
"This is the quantum analog of a switch that has several allowed positions, rather than just two," said Neeley. "Because it has more energy levels, the physics of a qudit is richer than for just a single qubit. This allows us to explore certain aspects of quantum mechanics that go beyond what can be observed with a qubit."
Just as bits are used as the fundamental building blocks of computers, qubits could one day be used as building blocks of a quantum computer, a device that exploits the laws of quantum mechanics to perform certain computations faster than can be done with classical bits alone. "Qudits can be used in quantum computers as well, and there are even cases where qudits could be used to speed up certain operations with a quantum computer," said Neeley. "Most research to date has focused on qubit systems, but we hope our experimental demonstration will motivate more effort on qudits, as an addition to the quantum information processing toolbox."
The senior co-author of the paper is John M. Martinis, professor of physics at UCSB. Other co-authors from UCSB are: Markus Ansmann, Radoslaw C. Bialczak, Max Hofheinz, Erik Lucero, Aaron D. O'Connell, Daniel Sank, Haohua Wang, James Wenner, and Andrew N. Cleland. Another co-author, Michael R. Geller, is from the University of Georgia.
Adapted from materials provided by University of California - Santa Barbara.

This Article Will Self-destruct: Tool To Make Online Personal Data Vanish

2009-07-22T08:41:00.001-07:00

SOURCE

ScienceDaily (July 22, 2009) — Computers have made it virtually impossible to leave the past behind. College Facebook posts or pictures can resurface during a job interview. A lost cell phone can expose personal photos or text messages. A legal investigation can subpoena the entire contents of a home or work computer, uncovering incriminating, inconvenient or just embarrassing details from the past.

The University of Washington has developed a way to make such information expire. After a set time period, electronic communications such as e-mail, Facebook posts and chat messages would automatically self-destruct, becoming irretrievable from all Web sites, inboxes, outboxes, backup sites and home computers. Not even the sender could retrieve them.
"If you care about privacy, the Internet today is a very scary place," said UW computer scientist Tadayoshi Kohno. "If people understood the implications of where and how their e-mail is stored, they might be more careful or not use it as often."
The team of UW computer scientists developed a prototype system called Vanish that can place a time limit on text uploaded to any Web service through a Web browser. After a set time text written using Vanish will, in essence, self-destruct. A paper about the project went public today and will be presented at the Usenix Security Symposium Aug. 10-14 in Montreal.
Co-authors on the paper are doctoral student Roxana Geambasu, assistant professor Tadayoshi Kohno, professor Hank Levy and undergraduate student Amit Levy, all with the UW's department of computer science and engineering. The research was funded by the National Science Foundation, the Alfred P. Sloan Foundation and Intel Corp.
"When you send out a sensitive e-mail to a few friends you have no idea where that e-mail is going to end up," Geambasu said. "For instance, your friend could lose her laptop or cell phone, her data could be exposed by malware or a hacker, or a subpoena could require your e-mail service to reveal your messages. If you want to ensure that your message never gets out, how do you do that?"
Many people believe that pressing the "delete" button will make their data go away.
"The reality is that many Web services archive data indefinitely, well after you've pressed delete," Geambasu said.
Simply encrypting the data can be risky in the long term, the researchers say. The data can be exposed years later, for example, by legal actions that force an individual or company to reveal the encryption key. Current trends in the computing and legal landscapes are making the problem more widespread.
"In today's world, private information is scattered all over the Internet, and we can't control the lifetime of that data," said Hank Levy. "And as we transition to a future based on cloud computing, where enormous, anonymous datacenters run the vast majority of our applications and store nearly all of our data, we will lose even more control."
The Vanish prototype washes away data using the natural turnover, called "churn," on large file-sharing systems known as peer-to-peer networks. For each message that it sends, Vanish creates a secret key, which it never reveals to the user, and then encrypts the message with that key. It then divides the key into dozens of pieces and sprinkles those pieces on random computers that belong to worldwide file-sharing networks, the same ones often used to share music or movie files. The file-sharing system constantly changes as computers join or leave the network, meaning that over time parts of the key become permanently inaccessible. Once enough key parts are lost, the original message can no longer be deciphered.
In the current Vanish prototype, the network's computers purge their memories every eight hours. (An option on Vanish lets users keep their data for any multiple of eight hours.)
Unlike existing commercial encryption services, a message sent using Vanish is kept private by an inherent property of the decentralized file-sharing networks it uses.
"A major advantage of Vanish is that users don't need to trust us, or any service that we provide, to protect or delete the data," Geambasu says.
Researchers liken using Vanish to writing a message in the sand at low tide, where it can be read for only a few hours before the tide comes in and permanently washes it away. Erasing the data doesn't require any special action by the sender, the recipient or any third party service.
"Our goal was really to come up with a system where, through a property of nature, the message, or the data, disappears," Levy says.
Vanish was released today as a free, open-source tool that works with the Firefox browser. To work, both the sender and the recipient must have installed the tool. The sender then highlights any sensitive text entered into the browser and presses the "Vanish" button. The tool encrypts the information with a key unknown even to the sender.
That text can be read, for a limited time only, when the recipient highlights the text and presses the "Vanish" button to unscramble it. After eight hours the message will be impossible to unscramble and will remain gibberish forever.
Vanish works with any text entered into a Web browser: Web-based e-mail such as Hotmail, Yahoo and Gmail, Web chat, or the social networking sites MySpace and Facebook. The Vanish prototype now works only for text, but researchers said the same technique could work for any type of data, such as digital photos.
It is technically possible to save information sent with Vanish. A recipient could print e-mail and save it, or cut and paste unencrypted text into a word-processing document, or photograph an unscrambled message. Vanish is meant to protect communication between two trusted parties, researchers say.
"Today many people pick up the phone when they want to talk with a lawyer or have a private conversation," Kohno said. "But more and more communication is happening online. Vanish is designed to give people the same privacy for e-mail and the Web that they expect for a phone conversation."
The paper and research prototype are at http://vanish.cs.washington.edu.
Adapted from materials provided by University of Washington.

Program For Cyber Security 'Neighborhood Watch' Developed

2009-07-17T01:18:00.001-07:00

SOURCE

ScienceDaily (July 16, 2009) — U.S. Department of Energy laboratories fight off millions of cyber attacks every year, but a near real-time dialog between these labs about this hostile activity has never existed – until now.

Scientists at DOE's Argonne National Laboratory have devised a program that allows for Cyber Security defense systems to communicate when attacked and transmit that information to cyber systems at other institutions in the hopes of strengthening the overall cyber security posture of the complex.
"The Federated Model for Cyber Security acts as a virtual neighborhood watch program. If one institution is attacked; secure and timely communication to others in the Federation will aide in protecting them from that same attack through active response," cyber security officer Michael Skwarek said.
Prior to the development of the Federated Model for Cyber Security, the exchange of hostile activity was solely on the shoulders of the human element. In cyber attacks, every second counts and the quicker that such information can be securely shared, will assist in strengthening others against similar attacks. With millions of cyber security probes a day, the human element will not be successful alone.
"This program addresses the need for the exchange of hostile activity information, with the goal of reducing the time to react across the complex. History has shown, hostile activity is often targeted at more than one location, and having our defenses ready and armed will assist greatly." Skwarek said.
Currently, the program is capable of transmitting information regarding hostile IP addresses and domain names, and will soon be able to share hostile email address and web URLs to others in the Federation.
The development of this program led to Skwarek along with Argonne's cyber security team members Matt Kwiatkowski, Tami Martin, Scott Pinkerton, Chris Poetzel, Gene Rackow and Conrad Zadlo winning the DOE's 2009 Cyber Security Innovation and Technology Achievement Award.
The Federated Model for Cyber Security has proved to be an important cyber security and communication tool. Use in the private sector, as well as in institutions with heavy collaborative efforts, can realize an operational gain by leveraging the power of sharing and learning from others on what they see and defend against on a daily basis.
Adapted from materials provided by DOE/Argonne National Laboratory.

Tracking The Life And Death Of News

2009-07-14T00:45:00.001-07:00

SOURCE

ScienceDaily (July 14, 2009) — As more and more news appears on the Internet as well as in print, it becomes possible to map the global flow of news by observing it online. Using this strategy, Cornell computer scientists have managed to track and analyze the "news cycle" -- the way stories rise and fall in popularity.

Jon Kleinberg, the Tisch University Professor of Computer Science at Cornell, postdoctoral researcher Jure Leskovec and graduate student Lars Backstrom tracked 1.6 million online news sites, including 20,000 mainstream media sites and a vast array of blogs, over the three-month period leading up to the 2008 presidential election -- a total of 90 million articles, one of the largest analyses anywhere of online news. They found a consistent rhythm as stories rose into prominence and then fell off over just a few days, with a "heartbeat" pattern of handoffs between blogs and mainstream media. In mainstream media, they found, a story rises to prominence slowly then dies quickly; in the blogosphere, stories rise in popularity very quickly but then stay around longer, as discussion goes back and forth. Eventually though, almost every story is pushed aside by something newer.
"The movement of news to the Internet makes it possible to quantify something that was otherwise very hard to measure -- the temporal dynamics of the news," said Kleinberg. "We want to understand the full news ecosystem, and online news is now an accurate enough reflection of the full ecosystem to make this possible. This is one [very early] step toward creating tools that would help people understand the news, where it's coming from and how it's arising from the confluence of many sources."
The researchers also say their work suggests an answer to a longstanding question: Is the "news cycle" just a way to describe our perception of what's going on in the media, or is it a real phenomenon that can be measured? They opt for the latter, and offer a mathematical explanation of how it works.
The research was presented at the Association for Computing Machinery Special Interest Group on Conference on Knowledge Discovery and Data Mining Conference June 28-July 1 in Paris.
The ideal, Kleinberg said, would be to track "memes," or ideas, through cyberspace, but deciding what an article is about is still a major challenge for computing. The researchers sidestepped that obstacle by tracking quotations that appear in news stories, since quotes remain fairly consistent even though the overall story may be presented in very different ways by different writers.
Even quotes may change slightly or "mutate" as they pass from one article to another, so the researchers developed an algorithm that could identify and group similar but slightly different phrases. In simple terms, the computer identified short phrases that were part of longer phrases, using those connections to create "phrase clusters." Then they tracked the volume of posts in each phrase cluster over time. In the August and September data they found threads rising and falling on a more or less weekly basis, with major peaks corresponding to the Democratic and Republican conventions, the "lipstick on a pig" discussion, rising concern over the financial crisis and discussions of a bailout plan.
The slow rise of a new story in the mainstream, the researchers suggest, results from imitation -- as more sites carried a story, other sites were more likely to pick it up. But the life of a story is limited, as new stories quickly push out the old. A mathematical model based on the interaction of imitation and recency predicted the pattern fairly well, the researchers said, while predictions based on either imitation or recency alone couldn't come close.
Watching how stories moved between mainstream media and blogs revealed a sharp dip and rise the researchers described as a "heartbeat." When a story first appears, there is a small rise in activity in both spheres; as mainstream activity increases, the proportion blogs contribute becomes small; but soon the blog activity shoots up, peaking an average of 2.5 hours after the mainstream peak. Almost all stories started in the mainstream. Only 3.5 percent of the stories tracked appeared first dominantly in the blogosphere and then moved to the mainstream.
The mathematical model needs to be refined, the researchers said, and they suggested further study of how stories move between sites with opposing political orientation. "It will be useful to further understand the roles different participants play in the process," the researchers concluded, "as their collective behavior leads directly to the ways in which all of us experience news and its consequences."
Adapted from materials provided by Cornell University.

Quantum Computers And Tossing A Coin In The Microcosm

2009-07-10T01:26:00.001-07:00

SOURCE

ScienceDaily (July 9, 2009) — When you toss a coin, you either get heads or tails. By contrast, things are not so definite at the microcosmic level. An atomic 'coin' can display a superposition of heads and tails when it has been thrown. However, this only happens if you do not look at the coin. If you do, it decides in favour of one of the two states. If you leave the decision where a quantum particle should go to a coin like this, you get unusual effects. For the first time, physicists at the University of Bonn have demonstrated these effects in an experiment with caesium.

Let's assume we carried out the following experiment: we put a coin in the hand of a test person. We'll simply call this person Hans. Hans's task is now to toss the coin several times. Whenever the coin turns up 'heads', his task is to take a step to the right. By contrast, if it turns up 'tails', he takes a step to the left. After 10 throws we look where Hans is standing. Probably he won't have moved too far from his initial position, as 'heads' and 'tails' turn up more or less equally often. In order to walk 10 paces to the right, Hans would have to get 10 'heads' successively. And that tends not happen that often.
Now, we assume that Hans is a very patient person. He is so patient that he does this experiment 1000 times successively. After each go, we record his position. When at the end we display this result as a graph, we get a typical bell curve. Hans very often ends up somewhere close to his starting positions after 10 throws. By contrast, we seldom find him far to the left or right.
The experiment is called a 'random walk'. The phenomenon can be found in many areas of modern science, e.g. as Brownian motion. In the world of quantum physics, there is an analogy with intriguing new properties, the 'quantum walk'. Up to now, this was a more or less a theoretical construct, but physicists at the University of Bonn have now actually carried out this kind of 'quantum walk'.
A single caesium atom held in a kind of tweezers composed of laser beams served as a random walker and coin at the same time. Atoms can adopt different quantum mechanical states, similar to head and tails of a coin facing upwards. Yet at the microcosmic level everything is a little more complicated. This is because quantum particles can exist in a superposition of different states. Basically, in that case 'a bit of heads' and 'a bit of tails' are facing upwards. Physicists also call this superposition.
Using two conveyor belts made of laser beams, the Bonn physicists pulled their caesium atom in two opposite directions, the 'heads' part to the right, the 'tails' part to the left. 'This way we were able to move both states apart by fractions of a thousandth of a millimetre,' Dr. Artur Widera from the Bonn Institute of Applied Physics explains. After that, the scientists 'threw the dice once more' and put each of both components into a superposition of heads and tails again.
After several steps of this 'quantum walk' a caesium atom like this that has been stretched apart is basically everywhere. Only when you measure its position does it 'decide' at which position of the 'catwalk' it wants to turn up. The probability of its position is predominantly determined by a second effect of quantum mechanics. This is due to two parts of the atom being able to reinforce themselves or annihilate themselves. As in the case of light physicists call this interference.
As in the example of Hans the coin thrower, you can now carry out this 'quantum walk' many times. You then also get a curve which reflects the atom's probability of presence. And that is precisely what the physicists from Bonn measured. 'Our curve is clearly different from the results obtained in classical random walks. It does not have its maximum at the centre, but at the edges,' Artur Widera's colleague Michal Karski points out. 'This is exactly what we expect from theoretical considerations and what makes the quantum walk so attractive for applications.' For comparison the scientists destroyed the quantum mechanical superposition after every single 'throw of the coin'. Then the 'quantum walk' becomes a 'random walk', and the caesium atom behaves like Hans. 'And that is exactly the effect we see,' Michal Karski says.
Professor Dieter Meschede's group has been working on the development of so-called quantum computers now for many years. With the 'quantum walk' the team has now achieved a further seminal step on this path. 'With the effect we have demonstrated, entirely new algorithms can be implemented,' Artur Widera explains. Search processes are one example. Today, if you want to trace a single one in a row of zeros, you have to check all the digits individually. The time taken therefore increases linearly with the number of digits. By contrast, using the 'quantum walk' algorithm the random walker can search in many different places simultaneously. The search for the proverbial needle in a haystack would thus be greatly speeded up.
Their research will be published in the July 10 issue of the scientific journal Science.
Adapted from materials provided by University of Bonn.

DIY Production In 'Second Life' Factory

2009-07-07T12:25:00.000-07:00

SOURCE

ScienceDaily (July 7, 2009) — Anyone who wants to can now produce their own vehicle in a factory on the “Second Life” Internet platform. They can program the industrial robots, and transport and assemble the individual parts themselves. Learning platforms provide relevant background information.

In the “transparent factory”, car enthusiasts can watch vehicles being assembled part by part, and a new system set up by researchers of the Fraunhofer Institute for Manufacturing Engineering and Automation IPA even enables users to try their own hand at producing a quad bike, a four-wheeled motorbike. They can switch on conveyor belts, program industrial robots, and paint the frame themselves. At the end, they can zoom out of the factory hall with their finished product without paying a single cent. How is this possible? Because the factory does not exist in the real world but on the Internet platform of “Second Life”, a virtual world through which users can move in the form of a virtual figure known as an “avatar”.
“With the ‘factory of eMotions’, we want to familiarize people with a modern, technically advanced factory. We also want to demonstrate how the latest media can set things in motion,” says IPA scientist
Stefan Seitz. “Second Life has grown steadily: While in 2007, between 20,000 and 40,000 people were simultaneously online at any given time, this number has now risen to between 50,000 and 80,000.” In the factory, users first of all indicate which quad model they would like to produce. Powerful or fuel-saving? Black, silver or red? What type of wheel rims? They can choose from a variety of models as they please. Once their avatar has made a choice, production can begin. The parts list is sent out, and all components are manufactured, assembled and subjected to a quality inspection. The avatar can watch the production process and interact at certain stages. Learning platforms located at various points in the factory hall provide users with relevant background information. How is the production process controlled? How does a press work?
“The main challenge lay in reproducing the control logic for production – in other words, teaching the system how to produce a part on Machine A, transport it to Machine B and mount it there. Until now, the ‘Second Life’ platform has offered no support for this,” says Seitz. The researchers have developed a modular system which also enables any other product to be made. Industrial companies and private users can use the building blocks to set up their own virtual factories. The scientists have even integrated a speech recognition system, so the machines and robots can also be controlled by telephone. The factory will be revealed to the public in early July on the occasion of the IPA’s 50th anniversary.
Adapted from materials provided by Fraunhofer-Gesellschaft.

Physicists Find Way To Control Individual Bits In Quantum Computers.

2009-07-07T10:42:00.001-07:00

SOURCE

ScienceDaily (July 7, 2009) — Physicists at the National Institute of Standards and Technology (NIST) have overcome a hurdle in quantum computer development, having devised a viable way to manipulate a single "bit" in a quantum processor without disturbing the information stored in its neighbors. The approach, which makes novel use of polarized light to create "effective" magnetic fields, could bring the long-sought computers a step closer to reality.

A great challenge in creating a working quantum computer is maintaining control over the carriers of information, the "switches" in a quantum processor while isolating them from the environment. These quantum bits, or "qubits," have the uncanny ability to exist in both "on" and "off" positions simultaneously, giving quantum computers the power to solve problems conventional computers find intractable – such as breaking complex cryptographic codes.
One approach to quantum computer development aims to use a single isolated rubidium atom as a qubit. Each such rubidium atom can take on any of eight different energy states, so the design goal is to choose two of these energy states to represent the on and off positions. Ideally, these two states should be completely insensitive to stray magnetic fields that can destroy the qubit's ability to be simultaneously on and off, ruining calculations. However, choosing such "field-insensitive" states also makes the qubits less sensitive to those magnetic fields used intentionally to select and manipulate them. "It's a bit of a catch-22," says NIST's Nathan Lundblad. "The more sensitive to individual control you make the qubits, the more difficult it becomes to make them work properly."
To solve the problem of using magnetic fields to control the individual atoms while keeping stray fields at bay, the NIST team used two pairs of energy states within the same atom. Each pair is best suited to a different task: One pair is used as a "memory" qubit for storing information, while the second "working" pair comprises a qubit to be used for computation. While each pair of states is field- insensitive, transitions between the memory and working states are sensitive, and amenable to field control. When a memory qubit needs to perform a computation, a magnetic field can make it change hats. And it can do this without disturbing nearby memory qubits.
The NIST team demonstrated this approach in an array of atoms grouped into pairs, using the technique to address one member of each pair individually. Grouping the atoms into pairs, Lundblad says, allows the team to simplify the problem from selecting one qubit out of many to selecting one out of two – which, as they show in their paper, can be done by creating an effective magnetic field, not with electric current as is ordinarily done, but with a beam of polarized light.
The polarized-light technique, which the NIST team developed, can be extended to select specific qubits out of a large group, making it useful for addressing individual qubits in a quantum processor without affecting those nearby. "If a working quantum computer is ever to be built," Lundblad says, "these problems need to be addressed, and we think we've made a good case for how to do it." But, he adds, the long-term challenge to quantum computing remains: integrating all of the required ingredients into a single apparatus with many qubits.
Journal reference:
N. Lundblad, J.M. Obrecht, I.B. Spielman, and J.V. Porto. Field-sensitive addressing and control of field-insensitive neutral-atom qubits. Nature Physics, July 5, 2009
Adapted from materials provided by National Institute of Standards and Technology (NIST).

Computer Scientists Develop Model For Studying Arrangements Of Tissue Networks By Cell Division

2009-07-03T05:20:00.000-07:00

SOURCE

ScienceDaily (July 3, 2009) — Computer scientists at Harvard have developed a framework for studying the arrangement of tissue networks created by cell division across a diverse set of organisms, including fruit flies, tadpoles, and plants.

The finding, published in the June 2009 issue of PLoS Computational Biology, could lead to insights about how multicellular systems achieve (or fail to achieve) robustness from the seemingly random behavior of groups of cells and provide a roadmap for researchers seeking to artificially emulate complex biological behavior.
"We developed a model that allows us to study the topologies of tissues, or how cells connect to each other, and understand how that connectivity network is created through generations of cell division," says senior author Radhika Nagpal, Assistant Professor of Computer Science at the Harvard School of Engineering and Applied Sciences (SEAS) and a core faculty member of the Wyss Institute for Biologically Inspired Engineering. "Given a cell division strategy, even if cells divide at random, very predictable 'signature' features emerge at the tissue level."
Using their computational model, Nagpal and her collaborators demonstrated that the regularity of the tissue, such as the percentage of hexagons and the overall cell shape distribution, can act as an indicator for inferring properties about the cell division mechanism itself. In the epithelial tissues of growing organisms, from fruit flies to humans, the ability to cope with often unpredictable variations (referred to as robustness) is critical for normal development. Rapid growth, entailing large amounts of cell division, must be balanced with the proper regulation of overall tissue and organ architecture.
"Even with modern imaging methods, we can rarely directly 'ask' the cell how it decided upon which way to divide. The computational tool allows us to generate and eliminate hypotheses about cell division. Looking at the final assembled tissue gives us a clue about what assembly process was used," explains Nagpal.
The model also sheds light on a prior discovery made by the team: that many proliferating epithelia, from plants to frogs, show a nearly identical cell shape distribution. While the reasons are not clear, the authors suggest that the high regularity observed in nature requires a strong correlation between how neighboring cells divide. While plants and fruit flies, for example, seem to have conserved cell shape distributions, the two organisms have, based on the computational and experimental evidence, evolved distinct ways of achieving such a pattern.
"Ultimately, the work offers a beautiful example of the way biological development can take advantage of very local and often random processes to create large-scale robust systems. Cells react to local context but still create organisms with incredible global predictability," says Nagpal.
In the future, the team plans to use their approach to detect and study various mutations that adversely affect cell division process in epithelial tissues. Epithelial tissues are common throughout animals and form important structures in humans from skin to the inner lining of organs. Deviations from normal division can result in abnormal growth during early development and to the formation of cancers in adults.
"One day we may even be able to use our model to help researchers understand other kinds of natural cellular networks, from tissues to geological crack formations, and, by taking inspiration from biology, design more robust computer networks," adds Nagpal.
Nagpal's collaborators included Ankit B. Patel and William T. Gibson, both at Harvard, and Dr. Matthew C. Gibson at Stower's Institute.
Adapted from materials provided by Harvard University, via EurekAlert!, a service of AAAS.

Optical Computer Closer: Optical Transistor Made From Single Molecule

2009-07-02T08:34:00.000-07:00

SOURCE

ScienceDaily (July 2, 2009) — ETH Zurich researchers have successfully created an optical transistor from a single molecule. This has brought them one step closer to an optical computer.

Internet connections and computers need to be ever faster and more powerful nowadays. However, conventional central processing units (CPUs) limit the performance of computers, for example because they produce an enormous amount of heat. The millions of transistors that switch and amplify the electronic signals in the CPUs are responsible for this. One square centimeter of CPU can emit up to 125 watts of heat, which is more than ten times as much as a square centimeter of an electric hotplate.
Photons instead of electrons
This is why scientists have been trying for some time to find ways to produce integrated circuits that operate on the basis of photons instead of electrons. The reason is that photons do not only generate much less heat than electrons, but they also enable considerably higher data transfer rates.
Although a large part of telecommunications engineering nowadays is based on optical signal transmission, the necessary encoding of the information is generated using electronically controlled switches. A compact optical transistor is still a long way off. Vahid Sandoghdar, Professor at the Laboratory of Physical Chemistry of ETH Zurich, explains that, “Comparing the current state of this technology with that of electronics, we are somewhat closer to the vacuum tube amplifiers that were around in the fifties than we are to today’s integrated circuits.”
However, his research group has now achieved a decisive breakthrough by successfully creating an optical transistor with a single molecule. For this, they have made use of the fact that a molecule’s energy is quantized: when laser light strikes a molecule that is in its ground state, the light is absorbed. As a result, the laser beam is quenched. Conversely, it is possible to release the absorbed energy again in a targeted way with a second light beam. This occurs because the beam changes the molecule’s quantum state, with the result that the light beam is amplified. This so-called stimulated emission, which Albert Einstein described over 90 years ago, also forms the basis for the principle of the laser.
Focusing on a nano scale
Jaesuk Hwang, first author of the study and a scientific member of Sandoghdar’s nano-optics group, explains that, “Amplification in a conventional laser is achieved by an enormous number of molecules.” By focusing a laser beam on only a single tiny molecule, the ETH Zurich scientists have now been able to generate stimulated emission using just one molecule. They were helped in this by the fact that, at low temperatures, molecules seem to increase their apparent surface area for interaction with light . The researchers therefore needed to cool the molecule down to minus 272 degrees Celsius (minus 457.6 degrees Fahrenheit), i.e. one degree above absolute zero. In this case, the enlarged surface area corresponded approximately to the diameter of the focused laser beam.
Switching light with light
By using one laser beam to prepare the quantum state of a single molecule in a controlled fashion, scientists could significantly attenuate or amplify a second laser beam. This mode of operation is identical to that of a conventional transistor, in which electrical potential can be used to modulate a second signal.
Thus component parts such as the new single molecule transistor may also pave the way for a quantum computer. Sandoghdar says, “Many more years of research will still be needed before photons replace electrons in transistors. In the meantime, scientists will learn to manipulate and control quantum systems in a targeted way, moving them closer to the dream of a quantum computer.”
Journal reference:
J. Hwang, M. Pototschnig, R. Lettow, G. Zumofen, A. Renn, S. Götzinger, V. Sandoghda. A single-molecule opzical transistor. Nature, 460, 76-80 DOI: 10.1038/nature08134
Adapted from materials provided by ETH Zurich.

Quantum Communications One Step Closer: Novel Ion Trap For Sensing Force And Light Developed

2009-07-01T08:24:00.001-07:00

SOURCE

ScienceDaily (July 1, 2009) — Miniature devices for trapping ions (electrically charged atoms) are common components in atomic clocks and quantum computing research. Now, a novel ion trap geometry demonstrated at the National Institute of Standards and Technology (NIST) could usher in a new generation of applications because the device holds promise as a stylus for sensing very small forces or as an interface for efficient transfer of individual light particles for quantum communications.

The "stylus trap," built by physicists from NIST and Germany's University of Erlangen-Nuremberg, is described in Nature Physics. It uses fairly standard techniques to cool ions with laser light and trap them with electromagnetic fields. But whereas in conventional ion traps, the ions are surrounded by the trapping electrodes, in the stylus trap a single ion is captured above the tip of a set of steel electrodes, forming a point-like probe. The open trap geometry allows unprecedented access to the trapped ion, and the electrodes can be maneuvered close to surfaces. The researchers theoretically modeled and then built several different versions of the trap and characterized them using single magnesium ions.
The new trap, if used to measure forces with the ion as a stylus probe tip, is about one million times more sensitive than an atomic force microscope using a cantilever as a sensor because the ion is lighter in mass and reacts more strongly to small forces. In addition, ions offer combined sensitivity to both electric and magnetic fields or other force fields, producing a more versatile sensor than, for example, neutral atoms or quantum dots. By either scanning the ion trap near a surface or moving a sample near the trap, a user could map out the near-surface electric and magnetic fields. The ion is extremely sensitive to electric fields oscillating at between approximately 100 kilohertz and 10 megahertz.
The new trap also might be placed in the focus of a parabolic (cone-shaped) mirror so that light beams could be focused directly on the ion. Under the right conditions, single photons, particles of light, could be transferred between an optical fiber and the single ion with close to 95 percent efficiency. Efficient atom-fiber interfaces are crucial in long-distance quantum key cryptography (QKD), the best method known for protecting the privacy of a communications channel. In quantum computing research, fluorescent light emitted by ions could be collected with similar efficiency as a read-out signal. The new trap also could be used to compare heating rates of different electrode surfaces, a rapid approach to investigating a long-standing problem in the design of ion-trap quantum computers.
Research on the stylus trap was supported by the Intelligence Advanced Research Projects Activity.
Journal reference:
R. Maiwald, D. Leibfried, J. Britton, J.C. Bergquist, G. Leuchs, and D.J. Wineland. Stylus ion trap for enhanced access and sensing. Nature Physics, Online June 28
Adapted from materials provided by National Institute of Standards and Technology.

Sunspots Revealed In Striking Detail By Supercomputers

2009-06-19T03:12:00.000-07:00

SOURCE

ScienceDaily (June 18, 2009) — In a breakthrough that will help scientists unlock mysteries of the Sun and its impacts on Earth, an international team of scientists led by the National Center for Atmospheric Research (NCAR) has created the first-ever comprehensive computer model of sunspots. The resulting visuals capture both scientific detail and remarkable beauty.

The high-resolution simulations of sunspot pairs open the way for researchers to learn more about the vast mysterious dark patches on the Sun's surface. Sunspots are associated with massive ejections of charged plasma that can cause geomagnetic storms and disrupt communications and navigational systems. They also contribute to variations in overall solar output, which can affect weather on Earth and exert a subtle influence on climate patterns.
The research, by scientists at NCAR and the Max Planck Institute for Solar System Research (MPS) in Germany, is being published June 18 in Science Express.
"This is the first time we have a model of an entire sunspot," says lead author Matthias Rempel, a scientist at NCAR's High Altitude Observatory. "If you want to understand all the drivers of Earth's atmospheric system, you have to understand how sunspots emerge and evolve. Our simulations will advance research into the inner workings of the Sun as well as connections between solar output and Earth's atmosphere."
Ever since outward flows from the center of sunspots were discovered 100 years ago, scientists have worked toward explaining the complex structure of sunspots, whose number peaks and wanes during the 11-year solar cycle. Sunspots encompass intense magnetic activity that is associated with solar flares and massive ejections of plasma that can buffet Earth's atmosphere. The resulting damage to power grids, satellites, and other sensitive technological systems takes an economic toll on a rising number of industries.
Creating such detailed simulations would not have been possible even as recently as a few years ago, before the latest generation of supercomputers and a growing array of instruments to observe the Sun. The model enables scientists to capture the convective flow and movement of energy that underlie the sunspots, which is not directly detectable by instruments.
The work was supported by the National Science Foundation, NCAR's sponsor. The research team improved a computer model, developed at MPS, that built upon numerical codes for magnetized fluids that had been created at the University of Chicago.
Computer model provides a unified physical explanation
The new simulations capture pairs of sunspots with opposite polarity. In striking detail, they reveal the dark central region, or umbra, with brighter umbral dots, as well as webs of elongated narrow filaments with flows of mass streaming away from the spots in the outer penumbral regions.
The model suggests that the magnetic fields within sunspots need to be inclined in certain directions in order to create such complex structures. The authors conclude that there is a unified physical explanation for the structure of sunspots in umbra and penumbra that is the consequence of convection in a magnetic field with varying properties.
The simulations can help scientists decipher the mysterious, subsurface forces in the Sun that cause sunspots. Such work may lead to an improved understanding of variations in solar output and their impacts on Earth.
Supercomputing at 76 trillion calculations per second
To create the model, the research team designed a virtual, three-dimensional domain that simulates an area on the Sun measuring about 31,000 miles by 62,000 miles and about 3,700 miles in depth - an expanse as long as eight times Earth's diameter and as deep as Earth's radius. The scientists then used a series of equations involving fundamental physical laws of energy transfer, fluid dynamics, magnetic induction and feedback, and other phenomena to simulate sunspot dynamics at 1.8 billion points within the virtual expanse, each spaced about 10 to 20 miles apart. For weeks, they solved the equations on NCAR's new bluefire supercomputer, an IBM machine that can perform 76 trillion calculations per second.
The work drew on increasingly detailed observations from a network of ground- and space-based instruments to verify that the model captured sunspots realistically.
The new model is far more detailed and realistic than previous simulations that failed to capture the complexities of the outer penumbral region. The researchers noted, however, that even their new model does not accurately capture the lengths of the filaments in parts of the penumbra. They can refine the model by placing the grid points even closer together, but that would require more computing power than is currently available.
"Advances in supercomputing power are enabling us to close in on some of the most fundamental processes of the Sun," says Michael Knoelker, director of NCAR's High Altitude Observatory and a co-author of the paper. "With this breakthrough simulation, an overall comprehensive physical picture is emerging for everything that observers have associated with the appearance, formation, dynamics, and the decay of sunspots on the Sun's surface."
The University Corporation for Atmospheric Research manages the National Center for Atmospheric Research under sponsorship by the National Science Foundation.
Adapted from materials provided by National Center for Atmospheric Research/University Corporation for Atmospheric Research.

Human Eye Inspires Advance In Computer Vision From Boston College Researchers

2009-06-19T03:09:00.001-07:00

SOURCE

ScienceDaily (June 18, 2009) — Inspired by the behavior of the human eye, Boston College computer scientists have developed a technique that lets computers see objects as fleeting as a butterfly or tropical fish with nearly double the accuracy and 10 times the speed of earlier methods.

The linear solution to one of the most vexing challenges to advancing computer vision has direct applications in the fields of action and object recognition, surveillance, wide-base stereo microscopy and three-dimensional shape reconstruction, according to the researchers, who will report on their advance at the upcoming annual IEEE meeting on computer vision.
BC computer scientists Hao Jiang and Stella X. Yu developed a novel solution of linear algorithms to streamline the computer's work. Previously, computer visualization relied on software that captured the live image then hunted through millions of possible object configurations to find a match. Further compounding the challenge, even more images needed to be searched as objects moved, altering scale and orientation.
Rather than combing through the image bank – a time- and memory-consuming computing task – Jiang and Yu turned to the mechanics of the human eye to give computers better vision.
"When the human eye searches for an object it looks globally for the rough location, size and orientation of the object. Then it zeros in on the details," said Jiang, an assistant professor of computer science. "Our method behaves in a similar fashion, using a linear approximation to explore the search space globally and quickly; then it works to identify the moving object by frequently updating trust search regions."
Trust search regions act as visual touchstones the computer returns to again and again. Jiang and Yu's solution focuses on the mathematically-generated template of an image, which looks like a constellation when lines are drawn to connect the stars. Using the researchers' new algorithms, computer software identifies an object using the template of a trust search region. The program then adjusts the trust search regions as the object moves and finds its mathematical matches, relaying that shifting image to a memory bank or a computer screen to record or display the object.
Jiang says using linear approximation in a sequence of trust regions enables the new program to maintain spatial consistency as an object moves and reduces the number of variables that need to be optimized from several million to just a few hundred. That increased the speed of image matching 10 times over compared with previous methods, he said.
The researchers tested the software on a variety of images and videos – from a butterfly to a stuffed Teddy Bear – and report achieving a 95 percent detection rate at a fraction of the complexity. Previous so-called "greedy" methods of search and match achieved a detection rate of approximately 50 percent, Jiang said.
Jiang will present the team's findings at the IEEE Conference on Computer Vision and Pattern Recognition 2009, which takes place June 20-25 in Miami.
Adapted from materials provided by Boston College, via EurekAlert!, a service of AAAS.

Hybrid System Of Human-Machine Interaction Created

2009-06-19T03:04:00.001-07:00

SOURCE

ScienceDaily (June 17, 2009) — Scientists at FAU have created a "hybrid" system to examine real-time interactions between humans and machines (virtual partners). By pitting human against machine, they open up the possibility of exploring and understanding a wide variety of interactions between minds and machines, and establishing the first step toward a much friendlier union of man and machine, and perhaps even creating a different kind of machine altogether.

For more than 25 years, scientists in the Center for Complex Systems and Brain Sciences (CCSBS) in Florida Atlantic University’s Charles E. Schmidt College of Science, and others around the world, have been trying to decipher the laws of coordinated behavior called “coordination dynamics”.
Unlike the laws of motion of physical bodies, the equations of coordination dynamics describe how the coordination states of a system evolve over time, as observed through special quantities called collective variables. These collective variables typically span the interaction of organism and environment. Imagine a machine whose behavior is based on the very equations that are supposed to govern human coordination. Then imagine a human interacting with such a machine whereby the human can modify the behavior of the machine and the machine can modify the behavior of the human.
In a groundbreaking study published in the June 3 issue of PLoS One and titled “Virtual Partner Interaction (VPI): exploring novel behaviors via coordination dynamics,” an interdisciplinary group of scientists in the CCSBS created VPI, a hybrid system of a human interacting with a machine. These scientists placed the equations of human coordination dynamics into the machine and studied real-time interactions between the human and virtual partners. Their findings open up the possibility of exploring and understanding a wide variety of interactions between minds and machines. VPI may be the first step toward establishing a much friendlier union of man and machine, and perhaps even creating a different kind of machine altogether.
“With VPI, a human and a ‘virtual partner’ are reciprocally coupled in real-time,” said Dr. J. A. Scott Kelso, the Glenwood and Martha Creech Eminent Scholar in Science at FAU and the lead author of the study. “The human acquires information about his partner’s behavior through perception, and the virtual partner continuously detects the human’s behavior through the input of sensors. Our approach is analogous to the dynamic clamp used to study the dynamics of interactions between neurons, but now scaled up to the level of behaving humans.”
In this first ever study of VPI, machine and human behaviors were chosen to be quite simple. Both partners were tasked to coordinate finger movements with one another. The human executed the task with the intention of performing in-phase coordination with the machine, thereby trying to synchronize his/her flexion and extension movements with those of the virtual partner’s.
The machine, on the other hand, executed the task with the competing goal of performing anti-phase coordination with the human, thereby trying to extend its finger when the human flexed and vice versa. Pitting machine against human through opposing task demands was a way the scientists chose to enhance the formation of emergent behavior, and also allowed them to examine each partner’s individual contribution to the coupled behavior. An intriguing outcome of the experiments was that human subjects ascribed intentions to the machine, reporting that it was “messing” with them.
“The symmetry between the human and the machine, and the fact that they carry the same laws of coordination dynamics, is a key to this novel scientific framework,” said co-author Dr. Gonzalo de Guzman, a physicist and research associate professor at the FAU center. “The design of the virtual partner mirrors the equations of motion of the human neurobehavioral system. The laws obtained from accumulated studies describe how the parts of the human body and brain self-organize, and address the issue of self-reference, a condition leading to complexity.”
One ready application of VPI is the study of the dynamics of complex brain processes such as those involved in social behavior. The extended parameter range opens up the possibility of systematically driving functional process of the brain (neuromarkers) to better understand their roles. The scientists in this study anticipate that just as many human skills are acquired by observing other human beings; human and machine will learn novel patterns of behavior by interacting with each other.
“Interactions with ever proliferating technological devices often place high skill demands on users who have little time to develop these skills,” said Kelso. “The opportunity presented through VPI is that equally useful and informative new behaviors may be uncovered despite the built-in asymmetry of the human-machine interaction.”
While stable and intermittent coordination behaviors emerged that had previously been observed in ordinary human social interactions, the scientists also discovered novel behaviors or strategies that have never previously been observed in human social behavior. The emergence of such novel behaviors demonstrates the scientific potential of the VPI human-machine framework.
Modifying the dynamics of the virtual partner with the purpose of inducing a desired human behavior, such as learning a new skill or as a tool for therapy and rehabilitation, are among several applications of VPI.
“The integration of complexity in to the behavioral and neural sciences has just begun,” said Dr. Emmanuelle Tognoli, research assistant professor in FAU’s CCSBS and co-author of the study. “VPI is a move away from simple protocols in which systems are ‘poked’ by virtue of ‘stimuli’ to understanding more complex, reciprocally connected systems where meaningful interactions occur.”
Research for this study was supported by the National Science Foundation program “Human and Social Dynamics,” the National Institute of Mental Health’s “Innovations Award,” “Basic and Translational Research Opportunities in the Social Neuroscience of Mental Health,” and the Office of Naval Research Code 30. Kelso’s research is also supported by the Pierre de Fermat Chaire d’Excellence and Tognoli’s research is supported by the Davimos Family Endowment for Excellence in Science.
Adapted from materials provided by Florida Atlantic University, via Newswise.

Endless Original Music: Computer Program Creates Music Based On Emotions

2009-06-05T06:44:00.000-07:00

SOURCE

ScienceDaily (June 2, 2009) — A group of researchers from the University of Granada (UGR) has developed Inmamusys, a software program that can create music in response to emotions that arise in the listener. By using artificial intelligence (AI) techniques, the program enables original, copyright-free and emotion-inspiring music to be played continuously.

UGR researchers Miguel Delgado, Waldo Fajardo and Miguel Molina decided to design a software program that would enable a person who knew nothing about composition to create music. The system they devised, using AI, is called Inmamusys, an acronym for Intelligent Multiagent Music System, and is able to compose and play music in real time.
If successful, this prototype, which has been described recently in the journal Expert Systems with Applications, looks likely to bring about great changes in terms of the intrusive and repetitive canned music played in public places.
Miguel Molina, lead author of the study, says that while the repertoire of such canned music is very limited, the new invention can be used to create a pleasant, non-repetitive musical environment for anyone who has to be within earshot throughout the day.
Everyone's ears have suffered the effects of repetitively-played canned music, be it in workplaces, hospital environments or during phone calls made to directory inquiries numbers. On this basis, the research team decided that it would be "very interesting to design and build an intelligent system able to generate music automatically, ensuring the correct degree of emotiveness (in order to manage the environment created) and originality (guaranteeing that the tunes composed are not repeated, and are original and endless)."
Inmamusys has the necessary knowledge to compose emotive music through the use of AI techniques. In designing and developing the system, the researchers worked on the abstract representation of the concepts necessary to deal with emotions and feelings. To achieve this, Molina says, "we designed a modular system that includes, among other things, a two-level multiagent architecture."
A survey was used to evaluate the system, with the results showing that users are able to identify the type of music composed by the computer. A person with no musical knowledge whatsoever can use this artificial musical composer, because the user need do nothing more than decide on the type of music."
Beneath the system's ease of use, Miguel Molina reveals that a complex framework is at work to allow the computer to imitate a feature as human as creativity. Aside from creativity, music also requires specific knowledge.
According to Molina, this "is usually something done by human beings, although they do not understand how they do it. In reality, there are numerous processes involved in the creation of music and, unfortunately, we still do not understand many of them. Others are so complex that we cannot analyse them, despite the enormous power of current computing tools. Nowadays, thanks to the advances made in computer sciences, there are areas of research -- such as artificial intelligence -- that seek to reproduce human behaviour. One of the most difficult facets of all to reproduce is creativity."
Farewell to copyright payments
Commercial development of this prototype will not only change the way in which research is carried out into the relationship between computers and emotions, the means of interacting with music and structures by which music is composed in the future. It will also serve, say the study's authors, to reduce costs.
According to the researchers, "music is highly present in our leisure and working environments, and a large number of the places we visit have canned music systems. Playing these pieces of music involves copyright payments. Our system will make these music copyright payments a thing of the past."
Journal reference:
Miguel Delgado; Waldo Fajardo; Miguel Molina-Solana. Inmamusys: Intelligent multiagent music system. Expert Systems with Applications, 2009; 36 (3): 4574 DOI: 10.1016/j.eswa.2008.05.028
Adapted from materials provided by Plataforma SINC, via AlphaGalileo.

Computer Graphics Researchers Simulate The Sounds Of Water And Other Liquids

2009-06-05T06:40:00.001-07:00

SOURCE

ScienceDaily (June 4, 2009) — Splash, splatter, babble, sploosh, drip, drop, bloop and ploop!

Those are some of the sounds that have been missing from computer graphic simulations of water and other fluids, according to researchers in Cornell's Department of Computer Science, who have come up with new algorithms to simulate such sounds to go with the images.
The work by Doug James, associate professor of computer science, and graduate student Changxi Zheng will be reported at the 2009 ACM SIGGRAPH conference Aug. 3-7 in New Orleans. It is the first step in a broader research program on sound synthesis supported by a $1.2 million grant from the Human Centered Computing Program of the National Science Foundation (NSF) to James, assistant professor Kavita Bala and associate professor Steve Marschner.
In computer-animated movies, sound can be added after the fact from recordings or by Foley artists. But as virtual worlds grow increasingly interactive and immersive, the researchers point out, sounds will need to be generated automatically to fit events that can't be predicted in advance. Recordings can be cued in, but can be repetitive and not always well matched to what's happening.
"We have no way to efficiently compute the sounds of water splashing, paper crumpling, hands clapping, wind in trees or a wine glass dropped onto the floor," the researchers said in their research proposal.
Along with fluid sounds, the research also will simulate sounds made by objects in contact, like a bin of Legos; the noisy vibrations of thin shells, like trash cans or cymbals; and the sounds of brittle fracture, like breaking glass and the clattering of the resulting debris.
All the simulations will be based on the physics of the objects being simulated in computer graphics, calculating how those objects would vibrate if they actually existed, and how those vibrations would produce acoustic waves in the air. Physics-based simulations also can be used in design, just as visual simulation is now, James said. "You can tell what it's going to sound like before you build it," he explained, noting that a lot of effort often goes into making things quieter.
In their SIGGRAPH paper, Zheng and James report that most of the sounds of water are created by tiny air bubbles that form as water pours and splashes. Moving water traps air bubbles on the scale of a millimeter or so. Surface tension contracts the bubbles, compressing the air inside until it pushes back and expands the bubble. The repeated expansion and contraction over milliseconds generates vibrations in the water that eventually make its surface vibrate, acting like a loudspeaker to create sound waves in the air.
The simulation method developed by the Cornell researchers starts with the geometry of the scene, figures out where the bubbles would be and how they're moving, computes the expected vibrations and finally the sounds they would produce. The simulation is done on a highly parallel computer, with each processor computing the effects of multiple bubbles. The researchers have fine-tuned the results by comparing their simulations with real water sounds.
Demonstration videos of simulations of falling, pouring, splashing and babbling water are available at http://www.cs.cornell.edu/projects/HarmonicFluids.
The current methods still require hours of offline computing time, and work best on compact sound sources, the researchers noted, but they said further development should make possible the real-time performance needed for interactive virtual environments and deal with larger sound sources such as swimming pools or perhaps even Niagara Falls. They also plan to approach the more complex collections of bubbles in foam or plumes.
The research reported in the SIGGRAPH paper was supported in part by an NSF Faculty Early Career Award to James, and by the Alfred P. Sloan Foundation, Pixar, Intel and Autodesk.
Adapted from materials provided by Cornell University. Original article written by Bill Steele.

The Future of The Web:Mozilla Labs Aurora - Concept Browser (Video by Adaptive Path, Internet Browser )

2009-05-24T23:37:00.000-07:00

Is a room-temperature, solid-state quantum computer mere fantasy?

2009-05-15T07:46:00.001-07:00

SOURCE

Marshall StonehamLondon Centre for Nanotechnology and Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK
Published April 27, 2009
Creating a practical solid-state quantum computer is seriously hard. Getting such a computer to operate at room temperature is even more challenging. Is such a quantum computer possible at all? If so, which schemes might have a chance of success?

In his 2008 Newton Medal talk, Anton Zeilinger of the University of Vienna said: “We have to find ways to build quantum computers in the solid state at room temperature—that’s the challenge.” [1] This challenge spawns further challenges: Why do we need a quantum computer anyway? What would constitute a quantum computer? Why does the solid state seem essential? And would a cooled system, perhaps with thermoelectric cooling, be good enough?
Some will say the answer is obvious. But these answers vary from “It’s been done already” to “It can’t be done at all.” Some of the “not at all” group believe high temperatures just don’t agree with quantum mechanics. Others recognize that their favored systems cannot work at room temperature. Some scientists doubt that serious quantum computing is possible anyway. Are there methods that might just be able to meet Zeilinger’s challenge?
The questions that challenge
What is a computer? Standard classical computers use bits for encoding numbers, and the bits are manipulated by the classical gates that can execute AND and OR operations, for example. A classical bit has a value of 0 or 1, according to whether some small subunit is electrically charged or uncharged. Other forms are possible: the bits for a classical spintronic computer might be spins along or opposite to a magnetic field. Even the most modest computers on sale today incorporate complex networks of a few types of gates to control huge numbers of bits. If there are so few bits that you can count them on your fingers, it can’t seriously be considered a computer.
What do we mean by quantum? Being sure a phenomenon is “quantum” isn’t simple. Quantum ideas aren’t intuitive yet. Could you convince your banker that quantum physics could improve her bank’s security? Perhaps three questions identify the issues. First, how do you describe the state of a system? The usual descriptors, wave functions and density matrices, underlie wavelike interference and entanglement. Entanglement describes the correlations between local measurements on two particles, which I call their “quantum dance.” Entanglement is the resource that could make quantum computing worthwhile. The enemy of entanglement is decoherence, just as friction is the enemy of mechanical computers. Second, how does this quantum state change if it is not observed? It evolves deterministically, described by the Schrödinger equation. The probabilistic results of measurements emerge when one asks the third question: how to describe observations and their effects. Measurement modifies entanglement, often destroying it, as it singles out a specific state. This is one way that you can tell if an eavesdropper intercepted your message in a quantum communications system.
Proposed quantum computers have qubits manipulated by a few types of quantum gates, in a complex network. But the parallels are not complete [2]. Each classical bit has a definite value, it can only be 0 or 1, it can be copied without changing its value, it can be read without changing its value and, when left alone, its value will not change significantly. Reading one classical bit does not affect other (unread) bits. You must run the computer to compute the result of a computation. Every one of those statements is false for qubits, even that last statement. There is a further difference. For a classical computer, the process is Load → Run → Read, whereas for a quantum computer, the steps are Prepare → Evolve → Measure, or, as in one case discussed later, merely Prepare → Measure.
Why do we need a quantum computer? The major reasons stem from challenges to mainstream silicon technology. Markets demand enhanced power efficiency, miniaturization, and speed. These enhancements have their limits. Future technology scenarios developed for the semiconductor industry’s own roadmap [3] imply that the number of electrons needed to switch a transistor should fall to just 1 (one single electron) before 2020. Should we follow this innovative yet incremental roadmap, and trust to new tricks, or should we seek a radical technology, with wholly novel quantum components operating alongside existing silicon and photonic technologies? Any device with nanoscale features inevitably displays some types of quantum behavior, so why not make a virtue of necessity and exploit quantum ideas? Quantum-based ideas may offer a major opportunity, just as the atom gave the chemical industry in the 19th century, and the electron gave microelectronics in the 20th century. Quantum sciences could transform 21st century technologies.
Why choose the solid state for quantum computing? Quantum devices nearly always mean nanoscale devices, ultimately because useful electronic wave functions are fairly compact [4]. Complex devices with controlled features at this scale need the incredible know-how we have acquired with silicon technology. Moreover, quantum computers will be operated by familiar silicon technology. Operation will be easier if classical controls can be integrated with the quantum device, and easiest if the quantum device is silicon compatible. And scaling up, the linking of many basic and extremely small units is a routine demand for silicon devices. With silicon technologies, there are also good ways to link electronics and photonics. So an ideal quantum device would not just meet quantum performance criteria, but would be based on silicon; it would use off-the-shelf techniques (even sophisticated ones) suitable for a near-future generation fabrication plant. A cloud on the horizon concerns decoherence: can entanglement be sustained long enough in a large enough system for a useful quantum calculation?
All the objections
It has been done already? Some beautiful work demonstrating critical steps, including initializing a spin system and transfer of quantum information, has been done at room temperature with nitrogen-vacancy (NV-) centers in diamond [5]. Very few qubits were involved, and scaling up to a useful computer seems unlikely without new ideas. But the combination of photons—intrinsically insensitive to temperature—with defects or dopants with long decoherence times leaves hope.
It can’t be done: serious quantum computing simply isn’t possible anyway. Could any quantum computer work at all? Is it credible that we can build a system big enough to be useful, yet one that isn’t defeated by loss of entanglement or degraded quantum coherence? Certainly there are doubters, who note how friction defeated 19th century mechanical computers. Others have given believable arguments that computing based on entanglement is possible [6]. Of course, it may prove that some hybrid, a sort of quantum-assisted classical computing, will prove the crucial step.
It can’t be done: quantum behavior disappears at higher temperatures. Confusion can arise because quantum phenomena show up in two ways. In quantum statistics, the quantal ħ appears as ħω/kT. When statistics matter most, near equilibrium, high temperatures T oppose the quantum effects of ħ. However, in quantum dynamics, ħ can appear unassociated with T, opening new channels of behavior. Quantum information processing relies on staying away from equilibrium, so the rates of many individual processes compete in complex ways: dynamics dominate. Whatever the practical problems, there is no intrinsic problem with quantum computing at high temperatures.
It can’t be done: the right qubits don’t exist. True, some qubits are not available at room temperature. These include superconducting qubits and those based on Bose-Einstein condensates. In Kane’s seminal approach [7], the high polarizability needed for phosphorus-doped silicon (Si:P) corresponds to a low ionization donor energy, so the qubits disappear (or decohere) at room temperature. In what follows, I shall look at methods without such problems.
What needs to be done: Implementing quantum computing
David DiVincenzo at IBM Research Labs devised a checklist [8] that conveniently defines minimal (but seriously challenging) needs for a credible quantum computer. There must be a well-defined set of quantum states, such as electron spin states, to use as qubits. One needs scalability, so that enough qubits (let’s say 20, though 200 would be better) linked by entanglement are available to make a serious quantum computer. Operation demands a means to initialize and prepare suitable pure quantum states, a means to manipulate qubits to carry out a desired quantum evolution, and means to read out the results. Decoherence must be slow enough to allow these operations.
What does this checklist imply for solid-state quantum computing? Are there solid-state systems with decoherence mechanisms, key energies, and qubit control systems that might work at useful temperatures, ideally room temperature? Solid-state technologies have good prospects for scalability. There is a good chance that there are ingenious ways to link the many qubits and quantum gates needed for almost any serious application. However, decoherence might be fast. This may be less of a problem than imagined, for fast operating speeds go hand in hand with fast decoherence. Fast processing needs strong interactions, and such strong interactions will usually cause decoherence [9].
For spin-based solid-state quantum computing, most routes to initialization group into four categories. First, there are optical methods (including microwaves), based on selection rules, such as those used for NV- experiments. Then there are spintronic approaches, using a source (perhaps a ferromagnet) of spin-polarized electrons or excitons. (Note that spins have been transferred over distances of nearly a micron at room temperature [10].) Then there are brute force methods aiming for thermal equilibrium in a very large magnetic field, where the ratio of Zeeman splitting to thermal energy kBT is large. And finally there are tricks involving extra qubits that are not used in calculations. Of these methods, the optical and spintronic concepts seem most promising for room-temperature operation.
For readout, there are two broad strategies. Most ideas for spin-based quantum information processing aim at the sequential readout of individual spins. However, there are other less-developed ideas in which the ensemble of relevant spins is looked at together, as in some neutron scattering studies of antiferromagnetic crystals. What methods are there for probing single spins, if the sequential strategy is chosen? First, there is direct frequency discrimination, including the use of Zeeman splitting, of hyperfine structure, and so on. Ideas from atom trap experiments suggest that one can continue to interrogate a spin with a sequence of photons that do not change the qubit [11]. Such methods might work at room temperature, at least if the relevant spectral lines remain sharp enough. Second, there are many ways to exploit spin-dependent rates of carrier scatter or trapping. One might examine how mobile polarized spins are scattered by a fixed spin that is to be measured. Or the spin of a mobile carrier might be measured by its propensity for capture or scatter by fixed spin, or by some combination of polarized mobile spins and interferometry. At room temperature, the problem is practice rather than principle, and acceptable methods seem possible. A third way is to use relative tunnel rates, where one spin state can be blocked. Tunneling-based methods can become very hard at higher temperatures. There are then various ideas, all of which seem to be both tricky and relatively slow, but I may be being pessimistic. These include the use of circularly polarized light and magneto-optics, the direct detection of spin resonance with a scanning tunneling microscope, the exploitation of large spin-orbit coupling, or the direct measurement of a force with a scanning probe having a magnetic tip.
For the manipulations during operation, probably the most important ways use electromagnetic radiation, whether optical, microwave or radio frequency. Other controls, such as ultrasonics or surface acoustic waves, are less flexible. Electromagnetic methods might well operate at room temperature. Other suggestions invoke nanoscale electrodes. I do not know of any that look both credible and scalable.
Hopes for higher temperature operation
In what follows, I shall concentrate on two proposals as examples, with apologies to those whose suggestions I am omitting. Both of the proposals use optical methods to control spins, but do so in wholly different ways. The first is a scheme for optically controlled spintronics that I, Andrew Fisher, and Thornton Greenland proposed [11, 12]. The second route exploits entanglement of states of distant atoms by interference [13] in the context of measurement-based quantum computing [14]. A broader discussion of the materials needed is given in Ref. [15].
Optically controlled spintronics [11, 12]. Think of a thin film of silicon, perhaps 10 nm thick, isotopically pure to avoid nuclear spins, on top of an oxide substrate (Fig. 1). The simple architecture described is essentially two dimensional. Now imagine the film randomly doped with two species of deep donor—one species as qubits, the other to control the qubits. In their ground states, these species should have negligible interactions. When a control donor is excited, the electron’s wave function spreads out more, and its overlap with two of the qubit donors will create an entangling interaction between those two qubits (Fig. 2). Shaped pulses of optical excitation of chosen control donors guide the quantum dance (entanglement) of chosen qubit donors [16].
For controlling entanglement in this way, typical donor spacings in silicon must be of the order of tens of nanometers. Optically, one can only address regions of the order of a wavelength across, say 1000 nm. The limit of optical spatial resolution is a factor 100 larger than donor spacings needed for entanglement. How can one address chosen pairs of qubits? The smallest area on which we can focus light contains many spins. The answer is to exploit the randomness inevitable in standard fabrication and doping. Within a given patch of the film a wavelength across, the optical absorptions will be inhomogeneously broadened from dopant randomness. Even the steps at the silicon interfaces are helpful because the film thickness variations shift transition energies from one dopant site to another. Light of different wavelengths will excite different control donors in this patch, and so manipulate the entanglements of different qubits. Reasonable assumptions suggest one might make use of perhaps 20 gates or so per patch. Controlled links among 20 qubits would be very good by present standards, though further scale up—the linking of patches—would be needed for a serious computer (Fig. 3). The optically controlled spintronics strategy [11, 12] separates the two roles: qubit spins store quantum information, and controls manipulate quantum information. These roles require different figures of merit.
To operate at room temperature, qubits must stay in their ground states, and their decoherence—loss of quantum information—must be slow enough. Shallow donors like Si:P or Si:Bi thermally ionize too readily for room-temperature operations, though one could demonstrate principles at low temperatures with these materials. Double donors like Si:Mg+ or Si:Se+ have ionization energies of about half the silicon band gap and might be deep enough. Most defects in diamond are stable at room temperature, including substitutional N in diamond and the NV- center on which so many experiments have been done.
What about decoherence? First, whatever enables entanglement also causes decoherence. This is why fast switching means fast decoherence, and slow decoherence implies slow switching. Optical control involves manipulation of the qubits by stimulated absorption and emission in controlled optical excitation sequences, so spontaneous emission will cause decoherence. For shallow donors, like Si:P, the excitation energy is less than the maximum silicon phonon energy; even at low temperatures, one-phonon emission causes rapid decoherence. Second, spin-lattice relaxation in qubit ground states destroys quantum information. Large spin-orbit coupling is bad news, so avoiding high atomic number species helps. Spin lattice relaxation data at room temperature are not yet available for those Si donors (like Si:Se+) where one-phonon processes are eliminated because their first excited state lies more than the maximum phonon energy above the ground state. In diamond at room temperature, the spin-lattice relaxation time for substitutional nitrogen is very good (~1 ms) and a number of other centers have times ~0.1 ms. Third, excited state processes can be problems, and two-photon ionization puts constraints on wavelengths and optical intensities. Fourth, the qubits could lose quantum information to the control atoms. This can be sorted out by choosing the right form of excitation pulses [16]. Fifth, interactions with other spins, including nuclear spins, set limits, but there are helpful strategies, like using isotopically pure silicon [17].
The control dopants require different criteria. The wave functions of electronically excited controls overlap and interact with two or more qubits to manipulate entanglements between these qubits. The transiently excited state wave function of the control must have the right spatial extent and lifetime. While centers like Si:As could be used to show the ideas, for room-temperature operation one would choose perhaps a double donor in silicon, or substitutional phosphorus in diamond. The control dopant must have sharp optical absorption lines, since what determines the number of independent gates available in a patch is the ratio of the spread of excitation energies, inhomogeneously broadened, to the (homogeneous) linewidth. The spread of excitation energies—inhomogeneous broadening is beneficial in this optical spintronics approach [11, 12]—has several causes, some controllable. Randomness of relative control-qubit positions and orientations is important, and it seems possible to improve the distribution by using self-organization to eliminate unusable close encounters. Steps on the silicon interfaces are also helpful, provided there are no unpaired spins. Overall, various experimental data and theoretical analyses indicate likely inhomogeneous widths are a few percent of the excitation energy.
A checklist of interesting systems as qubits or controls shows some significant gaps in knowledge of defects in solids. Surprisingly little is known about electronic excited states in diamond or silicon, apart from energies and (sometimes) symmetries. Little is known about spin lattice relaxation and excited state kinetics at temperatures above liquid nitrogen, except for the shallow donors that are unlikely to be good choices for a serious quantum computer. There are few studies of stabilities of several species present at one time. Can we be sure to have isolated P in diamond? Would it lose an electron to substitutional N to yield the useless species P+ and N- ? Will most P be found as the irrelevant (spin S=0) PV- center?
What limits the number of gates in a patch is the number of control atoms that can be resolved spectroscopically one from another. As the temperature rises, the lines get broader, so this number falls and scaling becomes harder. Note the zero phonon linewidth need not be simply related to the fraction of the intensity in the sidebands. Above liquid nitrogen temperatures, these homogeneous optical widths increase fast. Thus we have two clear limits to room-temperature operation. The first is qubit decoherence, especially from spin lattice relaxation. The second is control linewidths becoming too large, reducing scalability, which may prove a more powerful limit.
Entangled states of distant atoms or solid-state defects created by interference. A wholly different approach generates quantum entanglement between remote systems by performing measurements on them in a certain way [13]. The systems might be two diamonds, each containing a single NV- center prepared in specific electron spin states, the two centers tuned to have exactly the same optical energies (Fig. 4). The measurement involves “single shot” optical excitation. Both systems are exposed to a weak laser pulse that, on average, will achieve one excitation. The single system excited will emit a photon that, after passing though beam splitters and an interferometer, is detected without giving information as to which system was excited (Fig. 5). “Remote entanglement” is achieved, subject to some strong conditions. The electronic quantum information can be swapped to more robust nuclear states (a so-called brokering process). This brokered information can then be recovered when needed to implement a strategy of measurement-based quantum information processing [14].
The materials and equipment needs, while different from those of optically controlled spintronics, have features in common. For remote entanglement, a random distribution of centers is used, with one from each zone chosen because of their match to each other. The excitation energies of the two distant centers must stay equal very accurately, and this equality must be stable over time, but can be monitored. There are some challenges here, since there will be energy shifts when other defect species in any one of the systems change charge or spin state (the difficulty is present but less severe for the optical control approach). As for optically controlled spintronics [11, 12], scale-up requires narrow lines, and becomes harder at higher temperatures, though there are ways to reduce the problem. Remote entanglement needs interferometric stability, avoiding problems when there are different temperature fluctuations for the paths from the separate systems. Again, there are credible strategies to reduce the effects.
So is room-temperature quantum computing feasible?
Spectroscopy is a generic need for both optically controlled spintronics and remote entanglement approaches. Both need qubits (the electron qubit for the measurement-based approach) with slow decoherence, a significant multiple of switching times. Both need sharp optical transitions with weak phonon sidebands to avoid loss of quantum information. A few zero phonon lines do indeed remain sharp at room temperature. The sharp lines should have frequencies stable over extended times. This mix of properties is hard to meet, but by no means impossible.
Perhaps the hardest conditions have yet to be mentioned. A quantum gate is no more a quantum computer than a transistor is a classical computer. Putting all the components of a quantum computer together could prove really hard. System integration may be the ultimate challenge. Quantum information processing (QIP) will need to exploit standard silicon technology to run the quantum system; and QIP must work alongside a feasible laser optics system. The optical systems are seriously complicated, though each feature seems manageable. It may be necessary to go to architectures even more complicated than those I have described. It might even prove useful to combine elements of remote entanglement and optical spin control, whether this is regarded as using remote entanglement to link spin patches, or as having spin patches instead of NV- centers as nodes for remote entanglements. A short article like this has to miss out many features of importance, not least questions of error correction, but a major message is that, even in the most rudimentary approaches, we have to think through all of the system when talking of a possible computer.
And what would you do with a quantum computer if you had one? Proposals that do not demand room temperature range from probable, like decryption or directory searching, to the possible, like modeling quantum systems, and even to the difficult yet perhaps conceivable, like modeling turbulence. More frivolous applications, like the computer games that drive many of today’s developments, make much more sense if they work at ambient temperatures. And available quantum processing at room temperature would surely stimulate inventive new ideas, just as solid-state lasers led to compact disc technology.
Summing up, where do we stand? At liquid nitrogen temperatures, say 77 K, quantum computing is surely possible, if quantum computing is possible at all. At dry ice temperatures, say 195 K, quantum computing seems reasonably possible. At temperatures that can be reached by thermoelectric or thermomagnetic cooling, say 260 K, things are harder, but there is hope. Yet we know that small (say 2–3 qubit) quantum devices operate at room temperature. It seems likely, to me at least, that a quantum computer of say 20 qubits will operate at room temperature. I do not say it will be easy. Will such a QIP device be as portable as a laptop? I won’t rule that out, but the answer is not obvious on present designs.
Acknowledgments
This work was supported in part by EPSRC through its Basic Technologies program. I am especially grateful for input from Gabriel Aeppli, Polina Bayvell, Simon Benjamin, Ian Boyd, Andrea Del Duce, Andrew Fisher, Tony Harker, Andy Kerridge, Brendon Lovett, Stephen Lynch, Gavin Morley, Seb Savory, and Jason Smith. I am particularly grateful to Simon Benjamin and Stephen Lynch for preparing the initial versions of the figures.
References
http://www.iop.org/activity/awards/International%20Award/page_31978.html..
C. P. Williams and S. H. Clearwater, Ultimate Zero and One: Computing at the Quantum Frontier (Copernicus, New York, 2000)[Amazon][WorldCat].
International Technology Roadmap for Semiconductors, http://www.itrs.net/.
General discussions relevant here: R. W. Keyes, J. Phys. Condens. Matter 17, V9 (2005); R. W. Keyes, J. Phys. Condens. Matter 18, S703 (2006); T. P. Spiller and W. J. Munro, J. Phys. Condens. Matter 18, V1 (2006); R. Tsu, Int. J. High Speed Electronics and Systems 9, 145 (1998); R. W. Keyes, Appl. Phys. A 76, 737 (2003); M. I. Dyakonov, Future Trends in Microelectronics: Up the Nano Creek, edited by S. Luryi, J. Xu, and A. Zaslavsky (Wiley, Hoboken, NJ, 2007)[Amazon][WorldCat].
Examples include: E. van Oort, N. B. Manson, and M. Glasbeek, J. Phys. C 21, 4385 (1988); F. T. Charnock and T. A. Kennedy, Phys. Rev. B 64, 041201 (2001); J. Wrachtrup et al., Opt. Spectrosc. 91, 429 (2001); J. Wrachtrup and F. Jelezko, J. Phys. Condens. Matter 18, S807 (2006); R. Hanson, F. M. Mendoza, R. J. Epstein, and D. D. Awschalom, Phys. Rev. Lett. 97, 087601 (2006); A. D. Greentree, P. Olivero, M. Draganski, E. Trajkov, J. R. Rabeau, P. Reichart, B. C. Gibson, S. Rubanov, S. T. Huntington, D. N. Jamieson, and S. Prawer, J. Phys. Condens. Matter 18, S825 (2006).
M. B. Plenio and P. L. Knight, Philos. Trans. R. Soc. London A 453, 2017 (1997).
B. E. Kane, Nature 393, 133 (1998).
D. P. DiVincenzo and D. Loss, Superlattices Microstruct. 23, 419 (1998).
A. J. Fisher, Philos. Trans. R. Soc. London A 361, 1441 (2003); http://arxiv.org/abs/quant-ph/0211200v1..
V. Dediu, M. Murgia, F. C. Matacotta, C. Taliani, and S. Barbanera, Solid State Commun. 122, 181 (2002).
A. M. Stoneham, A. J. Fisher, and P. T. Greenland, J. Phys Condens. Matter 15, L447 (2003).
R. Rodriquez, A .J. Fisher, P. T. Greenland, and A. M. Stoneham, J. Phys. Condens. Matter 16, 2757 (2004).
C. Cabrillo, J. I. Cirac, P. García-Fernández, and P. Zoller, Phys. Rev. A 58, 1025 (1999).
S. C. Benjamin,B. W. Lovett and J. M. Smith, Laser Photonics Rev. (to be published).
A. M. Stoneham, Materials Today 11, 32 (2008).
A. Kerridge, A. H. Harker, and A. M. Stoneham, J. Phy. Condens. Matter 19, 282201 (2007); E. M. Gauger et al., New J. Phys. 10, 073027 (2008).
A. M. Tyryshkin, J. J. L. Morton, S. C. Benjamin, A. Ardavan, G. A. D. Briggs, J. W. Ager, and S. A. Lyon, J. Phys. Condens. Matter 18, S783 (2006).
About the Author
Marshall Stoneham
Marshall Stoneham is Emeritus Massey Professor of Physics at University College London. He is a Fellow of the Royal Society, and also of the American Physical Society and of the Institute of Physics. Before joining UCL in 1995, he was the Chief Scientist of the UK Atomic Energy Authority, which involved him in many areas of science and technology, from quantum diffusion to nuclear safety. He was awarded the Guthrie gold medal of the Institute of Physics in 2006, and the Royal Society’s Zeneca Prize in 1995. He is the author of over 500 papers, and of a number of books, including Theory of Defects in Solids, now an Oxford Classic, and The Wind Ensemble Sourcebook that won the 1997 Oldman Prize. Marshall Stoneham is based in the London Centre for Nanotechnology, where he finds the scope for new ideas especially stimulating. His scientific interests range from new routes to solid-state quantum computing through materials modeling to biological physics, where his work on the interaction of small scent molecules with receptors has attracted much attention. He is the co-founder of two physics-based firms.

The Origin of Artificial Species: Creating Artificial Personalities

2009-05-15T02:10:00.000-07:00

SOURCE

(Left) Rity was developed to test the world’s first robot “chromosomes,” which allow it to have an artificial genome-based personality. (Right) A representation of Rity’s artificial genome. Darker shades represent higher gene values, and red represents negative values. Image credit: Jong-Hwan Kim, et al. ©2009 IEEE.
(PhysOrg.com) -- Does your robot seem to be acting a bit neurotic? Maybe it's just their personality. Recently, a team of researchers has designed computer-coded genomes for artificial creatures in which a specific personality is encoded. The ability to give artificial life forms their own individual personalities could not only improve the natural interactions between humans and artificial creatures, but also initiate the study of “The Origin of Artificial Species,” the researchers suggest.

The first artificial creature to receive the genomic personality is Rity, a dog-like software character that lives in a virtual 3D world in a PC. Rity’s genome is composed of 14 chromosomes, which together are composed of a total of 1,764 genes, each with its own value. Rather than manually assign the gene values, which would be difficult and time-consuming, the researchers proposed an evolutionary process that generates a genome with a specific personality desired by a user. The process is described in a recent study by authors Jong-Hwan Kim of KAIST in Daejeon, Korea; Chi-Ho Lee of the Samsung Economic Research Institute in Seoul, Korea; and Kang-Hee Lee of Samsung Electronics Company, Ltd., in Suwon-si, Korea.
“This is the first time that an artificial creature like a robot or software agent has been given a genome with a personality,” Kim told PhysOrg.com. “I proposed a new concept of an artificial chromosome as the essence to define the personality of an artificial creature and to pass on its traits to the next generation, like a genetic inheritance. It is critical to provide an impression that the robot is a living creature. With this respect, having emotions enhances natural human-robot interaction for human-robot symbiosis in the coming years.”
As the researchers explain, an autonomous artificial creature - whether a physical robot or software agent - can behave, interact, and react to environmental stimuli. Rity, for example, can interact with humans in the physical world using information through a mouse, a camera, or a microphone, with 47 perceptions. For instance, a single click and double click on Rity are perceived as “patted” and “hit,” respectively. Dragging Rity slowly and softly is perceived as “soothed,” and dragging it quickly and wildly as “shocked.”
To react to these stimuli in real time, Rity relies on its internal states which are composed of three units - motivation, homeostasis, and emotion - and controlled by its internal control architecture. The three units have a total of 14 states, which are the basis of the 14 chromosomes: the motivation unit includes six states (curiosity, intimacy, monotony, avoidance, greed, and the desire to control); the homeostasis unit includes three states (fatigue, hunger, and drowsiness); and the emotion unit has five states (happiness, sadness, anger, fear, and neutral).
“In Rity, internal states such as motivation, homeostasis and emotion change according to the incoming perception,” Kim said. “If Rity sees its master, its emotion becomes happy and its motivation may be ‘greeting and approaching’ him or her. It means the change of internal states and the activated behavior accordingly is internal and external responses to the incoming stimulus.”
The internal control architecture processes incoming sensor information, calculates each value of internal states as its response, and sends the calculated values to the behavior selection module to generate a proper behavior. Finally, the behavior selection module probabilistically selects a behavior through a voting mechanism, where each reasonable behavior has its own voting value. Unreasonable behaviors are prevented with matrix masks, while a reflexive behavior module, which imitates an animal’s instinct, deals with urgent situations such as running into a wall and enables a more immediate response.
“Rity was developed to test the world's first robotic ‘chromosomes,’ which are a set of computerized DNA (Deoxyribonucleic acid) code for creating robots that can think, feel, reason, express desire or intention, and could ultimately reproduce their kind, and evolve as a distinct species in a virtual world,” Kim said. “Rity can express its feeling through facial expression and behavior just like a living creature.”
As the researchers explain, each of the 14 chromosomes in Rity’s genome is composed of three gene vectors: the fundamental gene vector, the internal-state-related gene vector, and the behavior-related gene vector. As each chromosome is represented by 2 F-genes, 47 I-genes, and 77 B-genes, Rity has 1,764 genes in total. Each gene can have a range of values represented by real numbers. While genes are inherited, mutations may also occur. The nature of the genetic coding is such that a single gene can influence multiple behaviors, and also a single behavior can be influenced by multiple genes.
Depending on the values of the genes, the researchers specified five personalities (“the Big Five personality dimensions”) and their opposites to classify an artificial creature’s personality traits: extroverted/introverted, agreeable/antagonistic, conscientious/negligent, openness/closeness, and neurotic/emotionally stable.
To demonstrate an artificial genome, the researchers used their evolutionary algorithm to generate two contrasting personalities for Rity - agreeable and antagonistic - and compare Rity’s behavior in the different cases. Running the algorithm through 3,000 generations took about 12 hours to generate a genome encoding a desired personality by a Pentium 4, 2 GHz processor. For comparison, the researchers also used manual and random processes to generate genomes with agreeable and antagonistic personalities, though neither outperformed the evolutionary algorithm in terms of personality consistency and similarity to desired personality. Finally, the researchers also verified the accuracy of the evolutionary genome encoding by observing how the artificial creature reacted to a series of stimuli.
“The genome is an essential one encoding a mechanism for growth, reproduction and evolution, which necessarily defines ‘The Origin of Artificial Species,’” Kim said. “It means the origin stems from a computerized genetic code, which defines the mechanism for growing, multiplying and evolving along with its propensity to ‘feel’ happy, sad, angry, sleepy, hungry, afraid, etc.”
As the researchers showed, a 2D representation of the genome can enable users to view the chromosomes of the three gene types and easily insert or delete certain chromosomes or genes related to an artificial creature’s personality.
In the future, the researchers plan to combine the genome-based personality with the artificial creature’s own experiences in order to influence the creature’s behavioral responses. They also plan to classify and standardize the different behaviors in order to generalize the artificial genome structure.
More information:
Robot Intelligence Technology Lab: http://rit.kaist.ac.kr/home/ArtificialCreatures
Jong-Hwan Kim, Chi-Ho Lee, and Kang-Hee Lee. “Evolutionary Generative Process for an Artificial Creature’s Personality.” IEEE Transactions on Systems, Man, and Cybernetics - Part C: Applications and Reviews, Vol. 39, No. 3, May 2009.
Copyright 2009 PhysOrg.com. All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com.

Faster Computers, Electronic Devices Possible After Scientists Create Large-area Graphene On Copper

2009-05-10T23:02:00.000-07:00

SOURCE

ScienceDaily (May 11, 2009) — The creation of large-area graphene using copper may enable the manufacture of new graphene-based devices that meet the scaling requirements of the semiconductor industry, leading to faster computers and electronics, according to a team of scientists and engineers at The University of Texas at Austin.

"Graphene could lead to faster computers that use less power, and to other sorts of devices for communications such as very high-frequency (radio-frequency-millimeter wave) devices," said Professor and physical chemist Rod Ruoff, one of the corresponding authors on the Science article. "Graphene might also find use as optically transparent and electrically conductive films for image display technology and for use in solar photovoltaic electrical power generation."
Graphene, an atom-thick layer of carbon atoms bonded to one another in a "chickenwire" arrangement of hexagons, holds great potential for nanoelectronics, including memory, logic, analog, opto-electronic devices and potentially many others. It also shows promise for electrical energy storage for supercapacitors and batteries, for use in composites, for thermal management, in chemical-biological sensing and as a new sensing material for ultra-sensitive pressure sensors.
"There is a critical need to synthesize graphene on silicon wafers with methods that are compatible with the existing semiconductor industry processes," Ruoff said. "Doing so will enable nanoelectronic circuits to be made with the exceptional efficiencies that the semiconductor industry is well known for."
Graphene can show very high electron- and hole-mobility; as a result, the switching speed of nanoelectronic devices based on graphene can in principle be extremely high. Also, graphene is "flat" when placed on a substrate (or base material) such as a silicon wafer and, thus, is compatible with the wafer-processing approaches of the semiconductor industry. The exceptional mechanical properties of graphene may also enable it to be used as a membrane material in nanoelectromechanical systems, as a sensitive pressure sensor and as a detector for chemical or biological molecules or cells.
The university researchers, including post-doctoral fellow Xuesong Li, and Luigi Colombo, a TI Fellow from Texas Instruments, Inc., grew graphene on copper foils whose area is limited only by the furnace used. They demonstrated for the first time that centimeter-square areas could be covered almost entirely with mono-layer graphene, with a small percentage (less than five percent) of the area being bi-layer or tri-layer flakes. The team then created dual-gated field effect transistors with the top gate electrically isolated from the graphene by a very thin layer of alumina, to determine the carrier mobility. The devices showed that the mobility, a key metric for electronic devices, is significantly higher than that of silicon, the principal semiconductor of most electronic devices, and comparable to natural graphite.
"We used chemical-vapor deposition from a mixture of methane and hydrogen to grow graphene on the copper foils," said Ruoff. "The solubility of carbon in copper being very low, and the ability to achieve large grain size in the polycrystalline copper substrate are appealing factors for its use as a substrate --along with the fact that the semiconductor industry has extensive experience with the use of thin copper films on silicon wafers. By using a variety of characterization methods we were able to conclude that growth on copper shows significant promise as a potential path for high quality graphene on 300-millimeter silicon wafers."
The university's effort was funded in part by the state of Texas, the South West Academy for Nanoelectronics (SWAN) and the DARPA CERA Center. Electrical and computer engineering Professor Sanjay Banerjee, a co-author of the Science paper, directs both SWAN and the DARPA Center.
"By having a materials scientist of Colombo's caliber with such extensive knowledge about all aspects of semiconductor processing and now co-developing the materials science of graphene with us, I think our team exemplifies what collaboration between industrial scientists and engineers with university personnel can be," said Ruoff, who holds the Cockrell Family Regents Chair #7. "This industry-university collaboration supports both the understanding of the fundamental science as well its application."
Other co-authors of the work not previously mentioned include: research associate Richard Piner of the Department of Mechanical Engineering; Assistant Professor Emanuel Tutuc of the Department of Electrical and Computer Engineering; post-doctoral fellows Jinho An, Weiwei Cai, Inhwa Jung, Aruna Velamakanni and Dongxing Yang in the Department of Mechanical Engineering; and graduate students Seyoung Kim and Junghyo Nah in the Department of Electrical and Computer Engineering.
Journal reference:
Li et al. Large-Area Synthesis of High-Quality and Uniform Graphene Films on Copper Foils. Science, 2009; DOI: 10.1126/science.1171245
Adapted from materials provided by University of Texas at Austin, via EurekAlert!, a service of AAAS.

NIST demonstrates method for reducing errors in quantum computing

2009-05-10T12:42:00.001-07:00

SOURCE

A team of researchers working at the National Institute of Standards and Technology in Boulder, Colo., have demonstrated the effectiveness of using microwave pulses to suppress errors in quantum bits, or qubits, the media for carrying and manipulating data in the still experimental field of quantum computing.
The dynamical decoupling technique using microwave pulses they tested is not new, said John Bollinger, lead scientist on the project.
“It’s something we borrowed from the [magnetic resonance imaging] community that was developed in the ’50s and ’60s,” Bollinger said. “Our work is a validation of an idea that has been out there.”
But the experiments also advanced the theories, said Michael J. Biercuk, a NIST researcher who took part in the work. By using new pulse sequences, researchers demonstrated that the number of errors introduced into quantum computing through environmental noise could be reduced by an order of magnitude. This means the expected error rate can be brought down to well below the threshold for fault tolerance in quantum computing.
The ability to suppress errors before they accumulate is important because qubits are to subject to the introduction of errors through stray electromagnetic “noise” in the environment. To date, there is no practical way to correct these qubit errors.
The work was described in the April 23 issue of Nature.
Quantum computing uses subatomic particles rather than binary bits to carry and manipulate information. While a traditional bit is either on or off, a 1 or a 0, a qubit can exist in both states simultaneously. Once harnessed, this superposition of states should let quantum computers extract patterns from possible outputs of huge computations without performing all of them, allowing them to crack complex problems not solvable by traditional binary computers.
The researchers used an array of about 1,000 ultracold beryllium ions held in a magnetic field as the qubits. Sequences of microwave pulses were used to reverse changes introduced into the quantum states. The pulses in effect decouple the qubits from electromagnetic noise in the environment.
Work on using the technique for suppressing quantum errors began a decade ago, Biercuk said. “Our work validated essentially all of the work” that had been done up to this point. It also introduced new ideas by moving the pulses relative to each other in the patterns, rather than increasing the number of pulses. The results showed an unexpectedly high rate of error suppression.

The novel pulse sequences are tailored to the specific noise environment. The effective sequences can be found quickly through an experimental feedback technique and were shown to significantly outperform other sequences. The researchers tested these sequences under realistic noise conditions for different qubit technologies, making their results broadly applicable.
Announcement of the work comes a little more than a month after other NIST researchers showed that a promising technique for correcting quantum errors would not work. The technique, called transversal encoded quantum gates, seemed simple at first. “But after substantial effort, no one was able to find a quantum code to do that,” said information theorist Bryan Eastin. “We were able to show that a way doesn’t exist.”
The transversal operations used by Eastin were a “specific case” of error correction, Biercuk said, and the work does not mean that error correction cannot be done in quantum computers. Effective techniques for suppressing errors would mean that any error correction method would also be more effective, since there would be fewer errors to deal with.
But quantum computing still is some years away. Biercuk said that practical quantum computing already has been demonstrated with arrays of several coupled qubits. “That is wonderful from an experimental point of view, but it is not useful,” he said.
A quantum computer useful for doing complex simulations would require an array of about 100 qubits, he said. “That’s at least a decade away.” A computer capable of doing cryptographic factoring on a scale that cannot be done effectively by traditional computers still is 20 to 30 years off, he said.

By William Jackson

Neural Networks Used To Improve Wind Speed Forecasting

2009-05-07T01:52:00.001-07:00

SOURCE

ScienceDaily (May 6, 2009) — A team of researchers from the University of Alcala (UAH) and the Complutense University in Madrid (UCM) have invented a new method for predicting the wind speed of wind farm aerogenerators. The system is based on combining the use of weather forecasting models and artificial neural networks and enables researchers to calculate the energy that wind farms will produce two days in advance.

"The aim of the hybrid method we have developed is to predict the wind speed in each of the aerogenerators in a wind farm", explained Sancho Salcedo, an engineer at the Escuela Politécnica Superior and co-author of the study, published on-line in the journal Renewable Energy.
In order to develop the new model, the scientists used information provided by the Global Forecasting System from the US National Centers for Environmental Prediction. The data from this system cover the entire planet with a resolution of approximately 100 kilometres and are available for free on the internet.
Researchers are able to make more detailed predictions by integrating the so-called ‘fifth generation mesoscale model (MM5), from the US National Center of Atmospheric Research, designed to enhance resolution to 15x15 kilometres.
"This information is still not enough to predict the wind speed of one particular aerogenerador, which is why we applied artificial neural networks," Salcedo clarified. These networks are automatic information learning and processing systems that simulate the workings of animal nervous systems. In this case, they use the temperature, atmospheric pressure and wind speed data provided by forecasting models, as well as the data gathered by the aerogenerators themselves.
With these data, once the system has been "trained", predictions regarding wind speed will be made between one and 48 hours in advance. Wind farms are obliged by law to supply these predictions to Red Eléctrica Española, the company that delivers electricity and runs the Spanish electricity system.
Salcedo says the method can be applied immediately: "If the wind speed of one aerogenerator can be predicted, then we can estimate how much energy it will produce. Therefore, by summing the predictions for each ‘aero', we can forecast the production of an entire wind farm." The method has already been used very successfully at the wind farm in Fuentasanta, in Albacete.
Millions of Euros could be saved
Researchers are continuing to improve the method and recently proposed the use of several global forecasting models instead of just one, according to an article published this year in Neurocomputing. As a result, several sets of observations are obtained, which are then applied to banks of neural networks to achieve a more accurate prediction of aerogenerator wind speeds.
The results obtained reveal an improvement of 2% in predictions compared to the previous model. "Although this may seem like a small improvement, it is really substantial, as we are talking about an improvement in predicting energy production that could be worth millions of euros, Salcedo concluded.
Journal references:
Salcedo-Sanz et al. Hybridizing the fifth generation mesoscale model with artificial neural networks for short-term wind speed prediction. Renewable Energy, 2009; 34 (6): 1451 DOI: 10.1016/j.renene.2008.10.017
Salcedosanz et al. Accurate short-term wind speed prediction by exploiting diversity in input data using banks of artificial neural networks. Neurocomputing, 2009; 72 (4-6): 1336 DOI: 10.1016/j.neucom.2008.09.010
Adapted from materials provided by Plataforma SINC.

”Are You Living in a Computer Simulation?”

2009-04-11T09:18:00.000-07:00

SOURCE

No longer relegated to the domain of science fiction or the ravings of street corner lunatics, the “simulation argument” has increasingly become a serious theory amongst academics, one that has been best articulated by philosopher Nick Bostrom.
In his seminal paper ”Are You Living in a Computer Simulation?” Bostrom applies the assumption of substrate-independence, the idea that mental states can reside on multiple types of physical substrates, including the digital realm. He speculates that a computer running a suitable program could in fact be conscious. He also argues that future civilizations will very likely be able to pull off this trick and that many of the technologies required to do so have already been shown to be compatible with known physical laws and engineering constraints.

Harnessing computational powerSimilar to futurists Ray Kurzweil and Vernor Vinge, Bostrom believes that enormous amounts of computing power will be available in the future. Moore’s Law, which describes an eerily regular exponential increase in processing power, is showing no signs of waning, nor is it obvious that it ever will.To build these kinds of simulations, a posthuman civilization would have to embark upon computational megaprojects. As Bostrom notes, determining an upper bound for computational power is difficult, but a number of thinkers have given it a shot. Eric Drexler has outlined a design for a system the size of a sugar cube that would perform 10^21 instructions per second. Robert Bradbury gives a rough estimate of 10^42 operations per second for a computer with a mass on order of a large planet. Seth Lloyd calculates an upper bound for a 1 kg computer of 5*10^50 logical operations per second carried out on ~10^31 bits – this would likely be done on a quantum computer or computers built of out of nuclear matter or plasma [check out this article and this article for more information].More radically, John Barrow has demonstrated that, under a very strict set of cosmological conditions, indefinite information processing (pdf) can exist in an ever-expanding universe.At any rate, this extreme level of computational power is astounding and it defies human comprehension. It’s like imagining a universe within a universe—and that’s precisely be how it may be used.Worlds within worlds“Let us suppose for a moment that these predictions are correct,” writes Bostrom. “One thing that later generations might do with their super-powerful computers is run detailed simulations of their forebears or of people like their forebears.” And because their computers would be so powerful, notes Bostrom, they could run many such simulations.This observation, that there could be many simulations, led Bostrom to a fascinating conclusion. It’s conceivable, he argues, that the vast majority of minds like ours do not belong to the original species but rather to people simulated by the advanced descendants of the original species. If this were the case, “we would be rational to think that we are likely among the simulated minds rather than among the original biological ones.”Moreover, there is also the possibility that simulated civilizations may become posthuman themselves. Bostrom writes:

"They may then run their own ancestor-simulations on powerful computers they build in their simulated universe. Such computers would be “virtual machines”, a familiar concept in computer science. (Java script web-applets, for instance, run on a virtual machine – a simulated computer – inside your desktop.) Virtual machines can be stacked: it’s possible to simulate a machine simulating another machine, and so on, in arbitrarily many steps of iteration...we would have to suspect that the posthumans running our simulation are themselves simulated beings; and their creators, in turn, may also be simulated beings".

Given this matrioshkan possibility, the number of “real” minds across all existence should be vastly outnumbered by simulated minds. The suggestion that we’re not living in a simulation must therefore address the apparent gross improbabilities in question.Again, all this presupposes, of course, that civilizations are capable of surviving to the point where it’s possible to run simulations of forebears and that our descendants desire to do so. But as noted above, there doesn’t seem to be any reason to preclude such a technological feat.

Next: Kurzweil’s nano neural nets.

George Dvorsky serves on the Board of Directors for the Institute for Ethics and Emerging Technologies. George is the Director of Operations for Commune Media, an advertising and marketing firm that specializes in marketing science. George produces Sentient Developments blog and podcast.

Quantum Computers Will Require Complex Software To Manage Errors

2009-04-10T11:27:00.000-07:00

SOURCE

ScienceDaily (Apr. 9, 2009) — Highlighting another challenge to the development of quantum computers, theorists at the National Institute of Standards and Technology (NIST) have shown that a type of software operation, proposed as a solution to fundamental problems with the computers’ hardware, will not function as some designers had hoped.

Quantum computers—if they can ever be realized—will employ effects associated with atomic physics to solve otherwise intractable problems. But the NIST team has proved that the software in question, widely studied due to its simplicity and robustness to noise, is insufficient for performing arbitrary computations. This means that any software the computers use will have to employ far more complex and resource-intensive solutions to ensure the devices function effectively.
Unlike a conventional computer’s binary on-off switches, the building blocks of quantum computers, known as quantum bits, or “qubits,” have the mind-bending ability to exist in both “on” and “off” states simultaneously due to the so-called “superposition” principle of quantum physics. Once harnessed, the superposition principle should allow quantum computers to extract patterns from the possible outputs of a huge number of computations without actually performing all of them. This ability to extract overall patterns makes the devices potentially valuable for tasks such as codebreaking.
One issue, though, is that prototype quantum processors are prone to errors caused, for example, by noise from stray electric or magnetic fields. Conventional computers can guard against errors using techniques such as repetition, where the information in each bit is copied several times and the copies are checked against one another as the calculation proceeds. But this sort of redundancy is impossible in a quantum computer, where the laws of the quantum world forbid such information cloning.
To improve the efficiency of error correction, researchers are designing quantum computing architectures so as to limit the spread of errors. One of the simplest and most effective ways of ensuring this is by creating software that never permits qubits to interact if their errors might compound one another. Quantum software operations with this property are called “transversal encoded quantum gates.” NIST information theorist Bryan Eastin describes these gates as a solution both simple to employ and resistant to the noise of error-prone quantum processors. But the NIST team has proved mathematically that transversal gates cannot be used exclusively, meaning that more complex solutions for error management and correction must be employed.
Eastin says their result does not represent a setback to quantum computer development because researchers, unable to figure out how to employ transversal gates universally, have already developed other techniques for dealing with errors. “The findings could actually help move designers on to greener pastures,” he says. “There are some avenues of exploration that are less tempting now.”
Journal reference:
Eastin et al. Restrictions on Transversal Encoded Quantum Gate Sets. Physical Review Letters, 2009; 102 (11): 110502 DOI: 10.1103/PhysRevLett.102.110502
Adapted from materials provided by National Institute of Standards and Technology.

Software Fits Flexible Components

2009-03-23T11:58:00.001-07:00

SOURCE

ScienceDaily (Mar. 23, 2009) — Can the newly designed dashboard be easily installed? What paths should the assembly robot take so that the cables do not hit against the car body? A new software program simulates assembly paths and also factors in the pliability of components.

Car component designers not only have to ensure that their designs are visually appealing, they also have to think about the assembly process: Can the designed dashboard be easily installed in the new car model? What assembly paths need to be taken so that the component does not hit and scratch the car body? Thanks to a new software program, components that only exist in the form of CAD data can be virtually installed in the new car model by the assembly planners. If a component is too large to be maneuvered into place, the program gives concrete advice on where to change its shape.
The software was developed and has now been further improved by researchers at the Fraunhofer-Chalmers Research Centre for Industrial Mathematics FCC in Gothenburg, Sweden, and the Fraunhofer Institute for Industrial Mathematics ITWM in Kaiserslautern. “We can also include the pliability of components in the assembly simulation,” says ITWM group manager Dr.-Ing. Joachim Linn. “In the CAD data, flexible components such as plastic parts for the passenger compartment appear rigid, but during assembly they have to be slightly bent and pressed.”
How much force needs to be applied to bend the dashboard far enough to install it in the car? Can the job be done by just one employee and are special tools required? How can flexible brake hoses be installed most efficiently? The researchers also simulate the use of assembly robots, whose flexible supply lines often scrape against the car body, leaving small scratches. The program computes how the robot should move and fit the parts so that the cables do not hit the bodywork.
These computations are fast – like the CAD programs the designers are used to. “You can work interactively with the program, for example to make a component longer or shorter in just a few seconds. For this purpose we slimmed down the highly accurate structure-mechanical computation processes. The results are still accurate enough but are delivered in real time,” says Linn. Assembly paths, too, are computed within minutes. The researchers will give a live demonstration of the program at the Hannover-Messe (Hall 17, Stand D60) from April 20 to 24. The software is due to be launched on the market before the end of the year; support services and training material are already available.
Adapted from materials provided by Fraunhofer-Gesellschaft, via AlphaGalileo.

Fuzzy Logic And Grey Science

2009-03-17T09:02:00.000-07:00

SOURCE

ScienceDaily (Mar. 17, 2009) — If something is true it cannot be false, and if something is false it cannot be true. The same can be said of black and white. This principle of classical logic is one of the mainstays of the scientific method, but it loses effectiveness in the grey areas between these absolutes.

In other words, classical logic cannot adequately quantify elements that are black but also white, and which can only be differentiated by applying arbitrary distinctions of shades such as light grey, dark grey, or very dark grey. How many grains of sand can a desert lose before we cease to consider it a desert? How many degrees does the temperature in a room have to drop for it to be cold?
Fuzzy logic provides a channel for dealing scientifically with these qualitative concepts. “It is an extension of classical logic used to quantify vagueness”, explains Eduard Alarcón, a lecturer in the Department of Electronic Engineering at the UPC.
The concept of fuzzy logic derives from an article called “Fuzzy sets” published in 1965 by the engineer Lofti A. Zadeh. Eduard Alarcón explains that, “in classical logic, according to Bertrand Russell, from a set of antecedents is derived a set of consequents”. The system is based on a combination of rules taking the form “if” (antecedent), followed by “then” (consequent). “In fuzzy logic, both the antecedents and the consequents are fuzzy sets, which aim to quantify the vagueness of the qualifiers”, says Alarcón.
Joan Domingo, of the Department of Automatic Control, explains how fuzzy sets are used in a lighting control system. The system parameters, he explains, are a set of between three and six adjectives that describe the light intensity as, for example, “very low, low, sufficient, high and very high”. A series of light readings are taken, and a value is assigned to indicate the degree to which each reading corresponds to each of the adjectives. Thus, a very weak light could be assigned a value of 0.6 for “very low”, 0.3 could be “low”, and 0.1 “sufficient”. Each measurement is split between different sets, and the degree to which it corresponds to each one is represented by a function.
The system then applies a series of rules of the type “if ... then ...”, which are defined by an expert or directly integrated into the system. Thus, a rule might be, “if the light is very low, then we need to apply very high lighting”. These rules are applied to the input data using a chip- or algorithm-based inference motor. The output of each inference rule is an area, and the area of intersection of all the outputs is the final result, which is then translated into an action over the physical environment to which the system is applied.
These expert systems are based on rules that apply fuzzy logic, and have been integrated into electrical appliances, cameras, air-conditioning systems, industrial control systems and information technology in the last few decades.
More efficient appliances
Fuzzy systems also have a range of domestic applications, such as a washing machine that uses less detergent and water for lighter loads, or a control system for maintaining a comfortable temperature without switching on or off each time the thermostat registers a certain value, and without creating sudden rises or drops in temperature. This smooth transition between temperatures is achieved thanks to the degrees and zones used by fuzzy sets. Eduard Alarcón explains that fuzzy sets are analytical mathematical sets that provide a graded description referring to a specific zone. Each zone is independent of the others, and is therefore responsible for a single control action. By processing input values as degrees of zones, fuzzy systems can interpolate the results of different zones, thus ensuring that the resulting action is less abrupt.
Joan Domingo emphasizes the decision-making speed of inference motors which, unlike conventional processors, work in millions of fuzzy logic inferences per second (MFLIPS). “Classical control systems are analogue and slow, whereas fuzzy systems are digital and run at incredibly high speeds. Fuzzy systems are very easy to use, relatively quick to install, and produce excellent results”, he explains.
In addition to the development of new systems and devices, theoretical advances are also being made. For example, the Research Group on Functional Mathematical Modeling and Applications is currently studying improved fuzzy classification methods for solving problems caused by linguistic ambiguity in the definition of adjectives and imprecise measurement devices.
Control systems are the key product of fuzzy logic in the field automation and control, but UPC researchers are also incorporating fuzzy logic into the design of systems that will improve the quality of life of users in other areas, such as aeronautics and medical image analysis.
Detecting cancer cells
Can cancer cells be detected in a uterine tissue sample? Until recently, to answer this question a pathologist would have had to spend hours over the microscope examining a cytology sample of uterine tissue provided by a gynecologist. Samples of this size contain millions of cells, and prolonged examination can lead to tiredness and increased probability of error.
To minimize this risk, a joint research team from the UPC and Rovira i Virgili University, directed by Pilar Sobrevilla, of the Department of Applied Mathematics II, and Eduard Montseny, of the Department of Automatic Control, is working with the Hospital de Sant Pau to develop an automatic cytology image analysis system. Pilar Sobrevilla explains that “the system, which is based on fuzzy logic, isolates all of the cells in the image and determines their degree of normality”.
The system examines the image and determines the possible presence of abnormal cells on the basis of color and texture. The result is then displayed in a new image that highlights the areas containing cancerous cells. The process can be performed in real time, as the pathologist simply has to feed the original image into the device to obtain a modified version highlighting the areas that need to be examined more thoroughly.
The system is already used by the Hospital de Sant Pau, and researchers are working on a second phase of the project that, explains Sobrevilla, will enable users to pinpoint potentially affected areas with greater precision and obtain data that can be tailored to the specific information required by the doctor.
The same research group has also designed a system which uses a fuzzy logic algorithm to grade the quality of corneal tissue used in transplants, the first version of which is already used by the Tissue Bank of the Hospital de Sant Pau in Barcelona. The system analyzes images of corneal tissue to determine whether it is of suitable quality for transplantation, and factors in data on the general health of potential donors to determine whether they meet the relevant health requirements.
Fuzzy logic can also be used to model the noise pollution produced by planes at take-off and landing. Xavier Prats, of the Department of Mechanical Engineering, takes the idea a step further in his doctoral thesis, which describes a system for defining the optimal trajectory during these maneuvers to minimize the noise pollution affecting local residents. Joseba Quevedo, the joint director of the thesis with Vincenç Puig, explains that new satellite navigation systems have made it possible for planes to follow curved trajectories during take-off and landing, rather than the straight ascents and descents required previously.
By altering the trajectory, it is also possible to reduce the noise pollution suffered by those living close to airports, the severity of which depends on the tolerance of individuals, and is not an objective parameter such as the level of sound produced. As Quevedo explains, “A patient in a hospital ward does not hear things in the same way as a young person shopping in a market, and the perceived level of a particular sound can vary enormously between day-time and night-time due to changes in the acoustic level of the surroundings”. The system uses fuzzy logic to analyze the level of noise pollution and grade the annoyance caused to people in local facilities (such as hospitals, schools and markets) and residential areas located close to the airport. The analysis also takes into account the time of day and the distance at which the plane passes the area.
Fuzzy logic and soft computing
In 1991, Lofti A. Zadeh, a professor at the University of Berkeley and the founder of fuzzy logic, coined the term ‘soft computing’. This branch of artificial intelligence deals with the design of expert systems capable of managing inexact, uncertain and/or incomplete information. Fuzzy logic is one of the principal techniques in this field, together with evolutionary algorithms and neural networks. More than 2000 experts in soft computing from around the world will meet in Barcelona in July 2010 for the lEEE World Congress on Computational Intelligence, organized by the UPC researcher Pilar Sobrevilla.
Adapted from materials provided by Universitat Politècnica de Catalunya.

Sending Out Internet Warnings For Outages, Viruses

2009-03-17T00:08:00.000-07:00

SOURCE

ScienceDaily (Mar. 17, 2009) — A long-overdue internet early warning system for Europe could help the region avoid deliberate or inadvertent outages, reduce the spread of new computer viruses, and ensure continuity of services.

Malte Hesse and Norbert Pohlmann of the Institute for Internet Security at the University of Applied Sciences Gelsenkirchen, Germany, point out that there is a growing need to improve the stability and trustworthiness of the internet, whether one is referring to web access, email, instant messaging and file transfer systems.
They add that raising awareness of critical processes and components on the internet among those responsible for their operation is essential. Moreover, there is a need to learn about internet use so that needs and service demands can be best catered for.
The internet is an incredibly diffuse network with no single, centralised control hub. Its complexity is not bounded by geographical, political, administrative or cultural borders, which means it presents an amazing challenge to the global society hoping to make best use of it and avoid criminal and terrorist activity that might occur online.
The internet's strength lies in this decentralised structure, but that also represents a problem in that it is not governed and consists of almost 30,000 autonomous systems each managed by individual organisations mostly within the private sector. The researchers obtained this figure using their AiconViewer tool developed by colleague Stefan Dierichs in 2006. Unfortunately, private organisations are exposed to a high level of competition, especially in times of recession, and this precludes the open exchange of important management information.
Nevertheless, if a European early warning system is to be built there is a need for a shift in attitude. "The cooperation of companies, organisations and governments is important to create a global view of the internet. By that we will be able to detect attacks in time and answer interesting research questions about the internet," the researchers say.
Early warning systems are present in various systems and are a crucial component of effective risk management in enterprises and for national homeland security systems. In order to create a European early warning system, funding has to be provided mainly by public sources in combination with income which can be generated through added value for the private partners, the researchers conclude.
Journal reference:
Malte Hesse and Norbert Pohlmann. European internet early warning system. International Journal of Electronic Security and Digital Forensics, 2009, 2, 1-17
Adapted from materials provided by Inderscience, via AlphaGalileo.

Breakthrough For Post-4G Communications

2009-03-16T10:14:00.000-07:00

SOURCE

ScienceDaily (Mar. 14, 2009) — With much of the mobile world yet to migrate to 3G mobile communications, let alone 4G, European researchers are already working on a new technology able to deliver data wirelessly up to 12.5Gb/s.

The technology – known as ‘millimetre (mm)-wave’ or microwave photonics – has commercial applications not just in telecommunications (access and in-house networks) but also in instrumentation, radar, security, radio astronomy and other fields.
Despite the quantum leap in performance made possible by combining the latest radio and optics technologies to produce mm-wave components, it will probably only be a few years before there are real benefits for the average EU citizen.
This is thanks to research and development work being done by the EU-funded project IPHOBAC, which brings together partners from both academia and industry with the aim of developing a new class of components and systems for mm-wave applications.
The mm-wave band is the extremely high frequency part of the radio spectrum, from 30 to 300 gigahertz (GHz), and it gets it name from having a wavelength of one to 10mm. Until now, the band has been largely undeveloped, so the new technology makes available for exploitation more of the scarce and much-in-demand spectrum.
New products from Europe
IPHOBAC is not simply a ‘paper project’ where the technology is researched, but very much a practical exercise to develop and commercialise a new class of products with a ‘made in Europe’ label on them.
While several companies in Japan and the USA have been working on merging optical and radio frequency technologies, IPHOBAC is the world’s first fully integrated effort in the field, with a lot of different companies involved. This has resulted in the three-year project, which runs until end-2009, already having an impressive list of achievements to its name.
It recently unveiled a tiny component, a transmitter able to transmit a continuous signal not only through the entire mm-wave band but beyond. Its full range is 30 to 325GHz and even higher frequency operation is now under investigation. The first component worldwide able to deliver that range of performance, it will be used in both communications and radar systems. Other components developed by the project include 110GHz modulators, 110GHz photodetectors, 300GHz dual-mode lasers, 60GHz mode-locked lasers, and 60GHz transceivers.
Truly disruptive technology
Project coordinator Andreas Stöhr says millimetre-wave photonics is a truly disruptive technology for high frequency applications. “It offers unique capabilities such as ultra-wide tunability and low-phase noise which are not possible with competing technologies, such as electronics,” he says.
What this will mean in practical terms is not only ultra-fast wireless data transfer over telecommunications networks, but also a whole range of new applications (http://www.iphobac-survey.org).
One of these, a 60GHz Photonic Wireless System, was demonstrated at the ICT 2008 exhibition in Lyon and was voted into the Top Ten Best exhibits. The system allows wireless connectivity in full high definition (HD) between devices in the home, such as a set-top box, TV, PC, and mobile devices. It is the first home area network to demonstrate the speeds necessary for full wireless HD of up to 3Gb/s.
The system can also be used to provide multi-camera coverage of live events in HD. “There is no time to compress the signal as the director needs to see live feed from every camera to decide which picture to use, and ours is the only technology which can deliver fast enough data rates to transmit uncompressed HD video/audio signals,” says Stöhr.
The same technology has been demonstrated for access telecom networks and has delivered world record data rates of up to 12.5Gb/s over short- to medium-range wireless spans, or 1500 times the speed of upcoming 4G mobile networks.
One way in which the technology can be deployed in the relatively short term, according to Stöhr, is wirelessly supporting very fast broadband to remote areas. “You can have your fibre in the ground delivering 10Gb/s but we can deliver this by air to remote areas where there is no fibre or to bridge gaps in fibre networks,” he says.
Systems for outer space
The project is also developing systems for space applications, working with the European Space Agency. Stöhr said he could not reveal details as this has not yet been made public, save to say the systems will operate in the 100GHz band and are needed immediately.
There are various ongoing co-operation projects with industry to commercialise the components and systems, and some components are already at a pre-commercial stage and are being sold in limited numbers. There are also ongoing talks with some of the biggest names in telecommunications, including Siemens, Ericsson, Thales Communications and Malaysia Telecom.
“In just a few years time everybody will be able to see the results of the IPHOBAC project in telecommunications, in the home, in radio astronomy and in space. It is a completely new technology which will be used in many applications even medical ones where mm-wave devices to detect skin cancer are under investigation,” says Stöhr.
Adapted from materials provided by ICT Results.

'Map Of Science' Shows Scientists' Virtual Trails Through Online Services

2009-03-16T09:20:00.000-07:00

SOURCE

ScienceDaily (Mar. 16, 2009) — Los Alamos National Laboratory scientists have produced the world's first Map of Science—a high-resolution graphic depiction of the virtual trails scientists leave behind when they retrieve information from online services.

The research, led by Johan Bollen, appeared recently in PLoS One. “This research will be a crucial component of future efforts to study and predict scientific innovation, as well novel methods to determine the true impact of articles and journals,” Bollen said.
While science is of tremendous societal importance, it is difficult to probe the often hidden world of scientific creativity. Most studies of scientific activity rely on citation data, which takes a while to become available because both the cited publication and the publication of a particular citation can take years to appear. In other words, citation data observes science as it existed years in the past, not the present.
Bollen and colleagues from LANL and the Santa Fe Institute collected usage-log data gathered from a variety of publishers, aggregators, and universities spanning a period from 2006 to 2008. Their collection totaled nearly 1 billion online information requests. Because scientists typically read articles online well before they can be cited in subsequent publications, usage data reveal scientific activity nearly in real-time. Moreover, because log data reflect the interactions of all users—such as authors, science practitioners, and the informed public—they do not merely reflect the activities of scholarly authors.
Whenever a scientist accesses a paper online from a publisher, aggregator, university, or similar publishing service, the action is recorded by the servers of these Web portals. The resulting usage data contains a detailed record of the sequences of articles that scientists download as they explore their present interests. After counting the number of times that scientists, across hundreds of millions of requests, download one article after another, the research team calculated the probability that an article or journal accessed by a scientist would be followed by a subsequent article or journal as part of the scientists’ online behavior. Based on such behavior, the researchers created a map that graphically portrays a network of connected articles and journals.
Bollen and colleagues were surprised by the map’s scope and detail. Whereas maps based on citations favor the natural sciences, the team’s maps of science showed a prominent and central position for the humanities and social sciences, which, in many places, acted like interdisciplinary bridges connecting various other scientific domains. Sections of the maps were shaped by the activities of practitioners who read the scientific literature but do not frequently publish in its journals.
The maps furthermore revealed unexpected relations between scientific domains that point to emerging relationships that are capturing the collective interest of the scientific community—for instance a connection between ecology and architecture.
“We were surprised by the fine-grained structure of scientific activity that emerges from our maps,” said Bollen.
According to Bollen, future work will focus on issues involved in the sustainable management of large-scale usage data, as well the production of models that explain the online behavior of scientists and how it relates to the emergence of scientific innovation. This information will help funding agencies, policy makers, and the public to better understand how best to tap the ebb and flow of scientific inquiry and discovery.
The research team includes Bollen, Herbert Van de Sompel, Ryan Chute, and Lyudmila Balakireva of LANL’s Digital Library Research and Prototyping Team and Aric Hagberg, Luis Bettencourt and Marko A Rodriguez of LANL’s Mathematical Modeling and Analysis Group, and LANL’s Center for Nonlinear Studies. Bettencourt also is part of the Santa Fe Institute.
Bollen and colleagues received funding from the Andrew W. Mellon foundation to examine the potential of large-scale usage data. The study is part of the MESUR (Metrics from Scholarly Usage of Resources) project of which Bollen is the principal investigator. The MESUR usage database is now considered the largest of its kind.
Adapted from materials provided by DOE/Los Alamos National Laboratory.

Fighting Tomorrow's Hackers: Keeping Encryption Safe From Future Quantum Computers

2009-03-15T06:26:00.001-07:00

SOURCE

ScienceDaily (Feb. 6, 2009) — One of the themes of Dan Brown’s The Da Vinci Code is the need to keep vital and sensitive information secure. Today, we take it for granted that most of our information is safe because it's encrypted. Every time we use a credit card, transfer money from our checking accounts -- or even chat on a cell phone -- our personal information is protected by a cryptographic system.

But the development of quantum computers threatens to shatter the security of current cryptographic systems used by businesses and banks around the world.
“We need to develop a new encryption system now, before our current systems -- such as RSA -- becomes instantly obsolete with the advent of the first quantum computer,” says Prof. Oded Regev at Tel Aviv University’s Blavatnik School of Computer Science. To accomplish that, Prof. Regev has proposed the first safe and efficient system believed to be secure against the massive computational power of quantum computers and backed by a mathematical proof of security.
Secure for Centuries
Prof. Regev stresses it is imperative that a new cryptographic system be developed and implemented as soon as possible. One reason is that current information, encrypted with RSA, could be retroactively hacked in the future, once quantum computers are available. That means that bank and other financial information, medical records, and even digital signatures could instantly become visible.
“You don’t want this information to remain secure for just 5 or 10 years until quantum computers are built,” says Prof. Regev. “You want it to be safe for the next century. We need to develop alternatives to RSA now, before it’s too late.”
New Cryptographic System
Cryptographic systems are used to transmit secure information such as bank and online transactions, and typically rely on the assumption that the factoring problem is difficult to solve. As a simplified example, if the number 3088433 were transmitted, an eavesdropper wouldn’t be able to tell that the number is derived from the factors 1583 and 1951. “Quantum computers can ‘magically’ break all of these factoring-based cryptographic systems, something that would take billions of years for current computers to accomplish,” Prof. Regev explains.
The current gold standard in encryption is the universally used RSA cryptosystem, which will be instantly broken once quantum computers are a reality -- an event predicted to happen as early as the next decade. To replace RSA in this new reality, Prof. Regev combined ideas from quantum computation with the research of other leaders in the field to create a system that is efficient enough to be practical for real-world applications.
Prof. Regev’s work was first announced in the ACM Symposium on Theory of Computing and will appear in the Journal of the Association for Computing Machinery. His work has now become the foundation for several other cryptographic systems developed by researchers from Stanford Research Institute, Stanford University, and MIT. Its potential real-world applications are extensive, ranging from banking transactions to eBay and other online auctions to digital signatures that can remain secure for centuries.
Adapted from materials provided by Tel Aviv University.

How Small Can Computers Get? Computing In A Molecule

2009-03-15T06:23:00.000-07:00

SOURCE

ScienceDaily (Dec. 30, 2008) — Over the last 60 years, ever-smaller generations of transistors have driven exponential growth in computing power. Could molecules, each turned into miniscule computer components, trigger even greater growth in computing over the next 60?

Atomic-scale computing, in which computer processes are carried out in a single molecule or using a surface atomic-scale circuit, holds vast promise for the microelectronics industry. It allows computers to continue to increase in processing power through the development of components in the nano- and pico scale. In theory, atomic-scale computing could put computers more powerful than today’s supercomputers in everyone’s pocket.
“Atomic-scale computing researchers today are in much the same position as transistor inventors were before 1947. No one knows where this will lead,” says Christian Joachim of the French National Scientific Research Centre’s (CNRS) Centre for Material Elaboration & Structural Studies (CEMES) in Toulouse, France.
Joachim, the head of the CEMES Nanoscience and Picotechnology Group (GNS), is currently coordinating a team of researchers from 15 academic and industrial research institutes in Europe whose groundbreaking work on developing a molecular replacement for transistors has brought the vision of atomic-scale computing a step closer to reality. Their efforts, a continuation of work that began in the 1990s, are today being funded by the European Union in the Pico-Inside project.
In a conventional microprocessor – the “motor” of a modern computer – transistors are the essential building blocks of digital circuits, creating logic gates that process true or false signals. A few transistors are needed to create a single logic gate and modern microprocessors contain billions of them, each measuring around 100 nanometres.
Transistors have continued to shrink in size since Intel co-founder Gordon E. Moore famously predicted in 1965 that the number that can be placed on a processor would double roughly every two years. But there will inevitably come a time when the laws of quantum physics prevent any further shrinkage using conventional methods. That is where atomic-scale computing comes into play with a fundamentally different approach to the problem.
“Nanotechnology is about taking something and shrinking it to its smallest possible scale. It’s a top-down approach,” Joachim says. He and the Pico-Inside team are turning that upside down, starting from the atom, the molecule, and exploring if such a tiny bit of matter can be a logic gate, memory source, or more. “It is a bottom-up or, as we call it, 'bottom-bottom' approach because we do not want to reach the material scale,” he explains.
Joachim’s team has focused on taking one individual molecule and building up computer components, with the ultimate goal of hosting a logic gate in a single molecule.
How many atoms to build a computer?
“The question we have asked ourselves is how many atoms does it take to build a computer?” Joachim says. “That is something we cannot answer at present, but we are getting a better idea about it.”
The team has managed to design a simple logic gate with 30 atoms that perform the same task as 14 transistors, while also exploring the architecture, technology and chemistry needed to achieve computing inside a single molecule and to interconnect molecules.
They are focusing on two architectures: one that mimics the classical design of a logic gate but in atomic form, including nodes, loops, meshes etc., and another, more complex, process that relies on changes to the molecule’s conformation to carry out the logic gate inputs and quantum mechanics to perform the computation.
The logic gates are interconnected using scanning-tunnelling microscopes and atomic-force microscopes – devices that can measure and move individual atoms with resolutions down to 1/100 of a nanometre (that is one hundred millionth of a millimetre!). As a side project, partly for fun but partly to stimulate new lines of research, Joachim and his team have used the technique to build tiny nano-machines, such as wheels, gears, motors and nano-vehicles each consisting of a single molecule.
“Put logic gates on it and it could decide where to go,” Joachim notes, pointing to what would be one of the world’s first implementations of atomic-scale robotics.
The importance of the Pico-Inside team’s work has been widely recognised in the scientific community, though Joachim cautions that it is still very much fundamental research. It will be some time before commercial applications emerge from it. However, emerge they all but certainly will.
“Microelectronics needs us if logic gates – and as a consequence microprocessors – are to continue to get smaller,” Joachim says.
The Pico-Inside researchers, who received funding under the ICT strand of the EU’s Sixth Framework Programme, are currently drafting a roadmap to ensure computing power continues to increase in the future.
Adapted from materials provided by ICT Results.

Quantum Computing Closer To Reality As Mathematicians Chase Key Breakthrough

2009-03-15T06:16:00.000-07:00

SOURCE

ScienceDaily (Dec. 23, 2008) — The ability to exploit the extraordinary properties of quantum mechanics in novel applications, such as a new generation of super-fast computers, has come closer following recent progress with some of the remaining underlying mathematical problems. In particular, the operator theory used to describe interactions between particles at atomic scales or smaller where quantum mechanical properties are significant needs to be enhanced to deal with systems where digital information is processed or transmitted.

In essence, the theory involves mathematical analysis based on Hilbert Spaces, which are extensions of the conventional three dimensional Euclidean geometry to cope with additional dimensions, as are required to describe quantum systems.
These challenges in mathematical analysis and prospects for imminent progress were discussed at a recent conference on operator theory and analysis organised by the European Science Foundation (ESF) in collaboration with the European Mathematical Society and the Mathematical Research and Conference Center in Bedlewo, Poland. The conference brought together some of the world's leading mathematical physicists and quantum mechanics specialists to tackle the key fields relating to spectral theory, according to the conference's co-chair Pavel Kurasov from the Lund Institute of Technology in Sweden. Among the participants were Uzy Smilansky, one of the leading authorities on quantum chaos, from the Weizmann Institute of Technology in Israel, and Vladimir Peller, specialist in pure mathematical analysis at Michigan State University in the US.
As Kurasov pointed out, a big challenge lies in extending current operator theory to describe and analyse quantum transport in wires, as will be needed for a new generation of quantum computers. Such computers will allow some calculations to be executed much more quickly in parallel by exploiting quantum coherence, whereby a processing element can represent digital bits in multiple states at once. There is also the prospect of exploiting another quantum mechanical property, quantum entanglement, for quantum cryptography where encryption key information can be transmitted with the ability to detect any attempt at tampering or eavesdropping, facilitating totally secure communication. In fact quantum cryptography has already been demonstrated over real telecommunications links and will be one of the first commercial applications based exclusively on quantum mechanics.
The operator theory required for quantum information processing and transmission is already well developed for what are known as self-adjoint operators, which are used to describe the different quantum states of an ideal system, but cannot be used for systems like a communications network where dissipation occurs. "So far only self-adjoint models have been considered, but in order to describe systems with dissipation even non-self-adjoint operators should be used," said Kurasov. The aim set out at the ESF conference was to extend the theory to non self-adjoint operators, which can be used to analyse real systems. "These operators may be used to describe quantum transport in wires and waveguides and therefore will be used in design of the new generation of computers," said Kurasov."Physicists are doing experiments with such structures, but the theory is not developed yet. An important question here is fitting of the parameters so that models will describe effects that may be observed in experiments." This question was discussed during inspiring lecture by Boris Pavlov from Auckland University, New Zealand – world leading specialist in mathematical analysis who became interested in physical applications.
Intriguingly Kurasov hinted that a breakthrough was likely before the next ESF conference on the subject in two years time, on the problem of reconstructing the so called quantum graphs used to represent states and interactions of quantum systems from actual observations. This will play a vital role in constructing the intermediate components of a quantum computer needed to monitor its own state and provide output.
Kurasov noted that this ESF conference was one in a series on the operator analysis field organized every second year, with proceedings published regularly in a book series Operator Theory: Advances and Applications.
The ESF conference Operator Theory, Analysis and Mathematical Physics was held at the Mathematical Research and Conference Center, Będlewo in Poland in June 2008
Adapted from materials provided by European Science Foundation.

Tracking Tigers In 3-D

2009-03-14T06:29:00.001-07:00

SOURCE

ScienceDaily (Mar. 12, 2009) — New software developed with help from the Wildlife Conservation Society will allow tiger researchers to rapidly identify individual animals by creating a three-dimensional model using photos taken by remote cameras. The software, described in an issue of the journal Biology Letters, may also help identify the origin of tigers from confiscated skins.

The new software, developed by Conservation Research Ltd., creates a 3D model from scanned photos using algorithms similar to fingerprint-matching software used by criminologists.
The study's authors include Lex Hiby of Conservation Research Ltd., Phil Lovell of the Gatty Marine Laboratory's Sea Mammal Research Unit, and Narendra Patil, N. Samba Kumar, Arjun N. Gopalaswamy and K. Ullas Karanth all of the Wildlife Conservation Society's India Program.
Researchers currently calculate tiger populations by painstakingly reviewing hundreds of photos of animals caught by camera "traps" and then matching their individual stripe patterns, which are unique to each animal. Using a formula developed by renowned tiger expert Ullas Karanth of WCS, researchers accurately estimate local populations by how many times individual tigers are "recaptured" by the camera trap technique.
It is expected that the new software will allow researchers to rapidly identify animals, which in turn could speed up tiger conservation efforts.
"This new software will make it much easier for conservationists to identify individual tigers and estimate populations," said Ullas Karanth, Senior Conservation Scientist at the Wildlife Conservation Society and one of the study's co-authors. "The fundamentals of tiger conservation are knowing how many tigers live in a study area before you can start to measure success."
The study's authors found that the software, which can be downloaded for free at: http://www.conservationresearch.co.uk, was up to 95 percent accurate in matching tigers from scanned photos. Researches were also able to use the software to identify the origin of confiscated tiger skins based on solely on photos. Development of the software was funded through a Panthera project in collaboration with WCS.
Facilities for obtaining the images used for the construction of the three-dimensional surface model were provided by the Thrigby Hall Zoo, Norfolk, England. Centre for Wildlife Studies, Bangalore and the Wildlife Conservation Society, India Program provided images, local resources and staff time for this study, which was supported in part by a grant from the Liz Claiborne / Art Ortenberg Foundation.
Adapted from materials provided by Wildlife Conservation Society, via EurekAlert!, a service of AAAS.

Random Network Connectivity Can Be Delayed, But With Explosive Results, New Study Finds

2009-03-14T06:25:00.000-07:00

SOURCE

ScienceDaily (Mar. 12, 2009) — In the life of many successful networks, the connections between elements increase over time. As connections are added, there comes a critical moment when the network's overall connectivity rises rapidly with each new link.

Now a trio of mathematicians studying networks in which the formation of connections is governed by random processes, has provided new evidence that super-connectivity can be appreciably delayed. But the delay comes at a cost: when it finally happens, the transition is virtually instantaneous, like a film of water abruptly crystallizing into ice.
The team's findings — described in a paper with an accompanying commentary in the March 13 issue of the journal Science —could be useful in a number of fields: from efforts by epidemiologists to control the spread of disease, to communications experts developing new products.
"We have found that by making a small change in the rules governing the formation of a network, we can greatly manipulate the onset of large-scale connectivity," said Raissa D'Souza, an associate professor of mechanical and aeronautical engineering at UC Davis.
In the classic model of random network formation, known as the Erdös-Rényi model, connections are added from among a large collection of points one at a time by randomly selecting a pair of points to connect. Two points are considered to be in the same group if it is possible to go from one to another along a continuous line of connections. A group remains very small until the number of connections reaches at least half the number of points. After that, the growth of the largest group follows a steep upward curve.
D'Souza, along with co-investigators Dimitris Achlioptas at UC Santa Cruz and Joel Spencer at New York University, wanted to explore how a network would change if there were an element of choice injected into its formation. In their mathematical model, they considered two random connections in each step, and selected only one. To make their choice, they multiplied the number of points in the group linked to one end of a connection by the number of points linked to its other end. And in each case, they chose the connection that yielded the lower product.
As they expected, this process delayed the onset of super-connectivity. But the team's analysis provided strong evidence for a new phenomenon: when a system is suppressed like this, it builds up a kind of pressure. "This algorithm yields a very violent transition," Achlioptas said, "reaching a critical moment at which the probability that two points are connected jumps from essentially zero to more than 50 percent instantaneously."
Their calculations for this model have provided important insights that could be broadly applicable to understanding and influencing the behavior of various kinds of networks, D'Souza said, adding that the work should also spark a quest for a mathematical proof to back their findings, an endeavor that may require new mathematics.
"Consider this," she said. "Often we are presented with two alternatives, and must choose one. We have no control over which alternatives are presented, but we certainly can control what we choose."
Adapted from materials provided by University of California - Davis, via EurekAlert!, a service of AAAS.

Moving Mountains With the Brain, Not a Joystick

2008-06-08T08:18:00.000-07:00

Source:

http://www.nytimes.com/2008/06/08/technology/08novel.html?ref=business

E-mail: novelties@nytimes.com

STILL using a mouse, keyboard, joystick or motion sensor to control the action in a video game? It may be time to try brain power instead.

A new headset system picks up electrical activity from the brain, as well as from facial muscles and other spots, and translates it into on-screen commands. This lets players vanquish villains not with a click, but with a thought.
Put on the headset, made by Emotiv Systems in San Francisco, and when a giant boulder blocks the path in a game you are playing, you can levitate it — not by something as crude as a keystroke, but just by concentrating on raising it, said Tan Le, Emotiv’s president. The headset captures electrical signals when you concentrate; then the computer processes these signals and pairs a screen action with them, like lifting a stone or repairing a falling bridge.
The headset is the consumer cousin of brain-computer interfaces developed in research labs and used, for example, by monkeys who manipulate prosthetic arms with thoughts. The monkeys’ intentions are detected by sensors, translated into machine language and used to move the arm. In general, some interfaces use sensors implanted directly in the brain; others use electrode-studded caps.
For humans, Emotiv plans to have its noninvasive, wireless EPOC headset ($299) on sale in time for Christmas, Ms. Le said. With 16 sensors that lightly touch the head, it uses a standard technology, electroencephalography, or EEG, to pick up electrical signals from the scalp’s surface and convert them to actions that control or enhance what happens on screen.
To help players master the art of moving on-screen objects solely through concentration, the headset will come bundled with a game, set on a magical mountain, that includes practice exercises, said Geoffrey Mackellar, Emotiv’s research and development manager. “You clear the mind,” he said, and then do 30 to 40 seconds of training, by concentrating, for instance, on visualizing a block lifting from the earth. “On the first or second attempt, you can lift it at will.”
Other, harder challenges follow. In constant feedback, he said, the machine learns more about how users think just as users grow more skillful at concentrating.
Many game developers are incorporating the EPOC’s biofeedback abilities into their applications, Ms. Le said.
The system doesn’t just lift boulders. It can also detect some of a player’s facial expressions and emotional responses: smile, frown or wink, for instance, and an avatar on screen can do so, too. Grow bored during a battle, and the system can detect ennui and supply a few dragons, or change the music. The device tracks a total of about 30 responses.
A chip inside the headset collects the signals and sends them wirelessly to a receiver plugged into a U.S.B. port of the computer, where most of the processing occurs, Dr. Mackellar said.
The sleek Emotiv headset is a version of the EEG cap used for decades to record brain electrical activity, said Nathan Fox, a professor of human development at the University of Maryland.
“There can be as many as 256 electrodes at one time in a cap,” he said. ‘The placement corresponds in some rough approximation to brain areas that are underneath the scalp.”
Medical-grade EEG caps are used in research to eavesdrop on the brain as it plans motion and to translate these plans, for example, into cursor actions on a screen so paralyzed people can control a computer to write messages.
The Emotiv headset, too, taps the power of the mind, as well as using feedback from muscles, Dr. Mackellar said.
“We definitely read brain waves — no doubt about it — but we also read other things,” he said. “In classical EEG, movements of the face and muscles are regarded as noise. But we use some of it, rather than discard it.”
Anton Nijholt, a professor of computer science at the University of Twente in the Netherlands who does research on innovative interfaces for games, looks forward to the extra means of interaction that EEG headsets will provide. But he doesn’t think that all consumers will be able to use them to raise mountains.
“Not all people are able to display the mental activity necessary to move an object on a screen,” he said. “Some people may not be able to imagine movement in a way that EEG can detect.”
So far, Dr. Mackellar said, all 200 testers of the headset had indeed been able to move on-screen objects mentally.
ANOTHER headset, the Neural Impulse Actuator ($169), just released by the OCZ Technology Group in Sunnyvale, Calif., has three sensors in a headband that pick up electrical activity primarily from muscles and convert it into commands, said Michael Schuette, vice president for technology development. Players of shooting games, for instance, may use eye movement to trigger a shot, shaving milliseconds off of their response time and sparing their hands.
The exact source of the electrical activity the headset is picking up may not be important, said Dr. Jonathan Wolpaw, chief of the laboratory for nervous system disorders at the Wadsworth Center of the New York State Department of Health in Albany. He uses EEG caps as part of brain-computer interfaces for severely paralyzed people. His systems record brain activity alone, but for a consumer game device, a cap that picks up a mixture of brain and muscle activity may be acceptable.
“In a lot of these commercial uses, people don’t care if the activity is coming from the brain or forehead muscles,” he said. “It doesn’t matter to them so long as they can play the game.”

Fausto Intilla - www.oloscience.com

New Image-recognition Software Could Let Computers 'See' Like Humans Do

2008-05-27T22:24:00.001-07:00

Source:

http://www.sciencedaily.com/releases/2008/05/080526000936.htm

ScienceDaily (May 26, 2008) — It takes surprisingly few pixels of information to be able to identify the subject of an image, a team led by an MIT researcher has found. The discovery could lead to great advances in the automated identification of online images and, ultimately, provide a basis for computers to see like humans do.

Antonio Torralba, assistant professor in MIT's Computer Science and Artificial Intelligence Laboratory, and colleagues have been trying to find out what is the smallest amount of information--that is, the shortest numerical representation--that can be derived from an image that will provide a useful indication of its content.
Deriving such a short representation would be an important step toward making it possible to catalog the billions of images on the Internet automatically. At present, the only ways to search for images are based on text captions that people have entered by hand for each picture, and many images lack such information. Automatic identification would also provide a way to index pictures people download from digital cameras onto their computers, without having to go through and caption each one by hand. And ultimately it could lead to true machine vision, which could someday allow robots to make sense of the data coming from their cameras and figure out where they are.
"We're trying to find very short codes for images," says Torralba, "so that if two images have a similar sequence [of numbers], they are probably similar--composed of roughly the same object, in roughly the same configuration." If one image has been identified with a caption or title, then other images that match its numerical code would likely show the same object (such as a car, tree, or person) and so the name associated with one picture can be transferred to the others.
"With very large amounts of images, even relatively simple algorithms are able to perform fairly well" in identifying images this way, says Torralba. He will be presenting his latest findings this June in Alaska at a conference on Computer Vision and Pattern Recognition. The work was done in collaboration with Rob Fergus at the Courant Institute in New York University and Yair Weiss of Hebrew University in Jerusalem.
To find out how little image information is needed for people to recognize the subject of a picture, Torralba and his co-authors tried reducing images to lower and lower resolution, and seeing how many images at each level people could identify.
"We are able to recognize what is in images, even if the resolution is very low, because we know so much about images," he says. "The amount of information you need to identify most images is about 32 by 32." By contrast, even the small "thumbnail" images shown in a Google search are typically 100 by 100.
Even an inexpensive current digital camera produces images consisting of several megapixels of data--and each pixel typically consists of 24 bits (zero or one) of data. But Torralba and his collaborators devised a mathematical system that can reduce the data from each picture even further, and it turns out that many images are recognizable even when coded into a numerical representation containing as little as 256 to 1024 bits of data.
Using such small amounts of data per image makes it possible to search for similar pictures through millions of images in a database, using an ordinary PC, in less than a second, Torralba says. And unlike other methods that require first breaking down an image into sections containing different objects, this method uses the entire image, making it simple to apply to large datasets without human intervention.
For example, using the coding system they developed, Torralba and his colleagues were able to represent a set of 12.9 million images from the Internet with just 600 megabytes of data--small enough to fit in the RAM memory of most current PCs, and to be stored on a memory stick. The image database and software to enable searches of the database, are being made publicly available on the web.
Of course, a system using drastically reduced amounts of information can't come close to perfect identification. At present, the matching works for the most common kinds of images. "Not all images are created equal," he says. The more complex or unusual an image is, the less likely it is to be correctly matched. But for the most common objects in pictures--people, cars, flowers, buildings--the results are quite impressive.
The work is part of research being carried out by hundreds of teams around the world, aimed at analyzing the content of visual information. Torralba has also collaborated on related work with other MIT researchers including William Freeman, a professor in the Department of Electrical Engineering and Computer Science; Aude Oliva, professor in the Department of Brain and Cognitive Sciences; and graduate students Bryan Russell and Ce Liu, in CSAIL. Torralba's work is supported in part by a grant from the National Science Foundation.
Torralba stresses that the research is still preliminary and that there will always be problems with identifying the more-unusual subjects. It's similar to the way we recognize language, Torralba says. "There are many words you hear very often, but no matter how long you have been living, there will always be one that you haven't heard before. You always need to be able to understand [something new] from one example."

Fausto Intilla - www.oloscience.com

Diamond-Like Crystals Discovered In Brazilian Beetle Solve Issue For Future Optical Computers

2008-05-21T11:48:00.001-07:00

Source:

http://www.sciencedaily.com/releases/2008/05/080520090534.htm

ScienceDaily (May 21, 2008) — Researchers have been unable to build an ideal "photonic crystal" to manipulate visible light, impeding the dream of ultrafast optical computers. But now, University of Utah chemists have discovered that nature already has designed photonic crystals with the ideal, diamond-like structure: They are found in the shimmering, iridescent green scales of a beetle from Brazil.

"It appears that a simple creature like a beetle provides us with one of the technologically most sought-after structures for the next generation of computing," says study leader Michael Bartl, an assistant professor of chemistry and adjunct assistant professor of physics at the University of Utah. "Nature has simple ways of making structures and materials that are still unobtainable with our million-dollar instruments and engineering strategies."
The study by Bartl, University of Utah chemistry doctoral student Jeremy Galusha and colleagues is set to be published in a forthcoming edition of the journal Physical Review E.
The beetle is an inch-long weevil named Lamprocyphus augustus. The discovery of its scales' crystal structure represents the first time scientists have been able to work with a material with the ideal or "champion" architecture for a photonic crystal.
"Nature uses very simple strategies to design structures to manipulate light -- structures that are beyond the reach of our current abilities," Galusha says.
Bartl and Galusha now are trying to design a synthetic version of the beetle's photonic crystals, using scale material as a mold to make the crystals from a transparent semiconductor.
The scales can't be used in technological devices because they are made of fingernail-like chitin, which is not stable enough for long-term use, is not semiconducting and doesn't bend light adequately.
The University of Utah chemists conducted the study with coauthors Lauren Richey, a former Springville High School student now attending Brigham Young University; BYU biology Professor John Gardner; and Jennifer Cha, of IBM's Almaden Research Center in San Jose, Calif.
Quest for the Ideal or 'Champion' Photonic Crystal
Researchers are seeking photonic crystals as they aim to develop optical computers that run on light (photons) instead of electricity (electrons). Right now, light in near-infrared and visible wavelengths can carry data and communications through fiberoptic cables, but the data must be converted from light back to electricity before being processed in a computer.
The goal -- still years away -- is an ultrahigh-speed computer with optical integrated circuits or chips that run on light instead of electricity.
"You would be able to solve certain problems that we are not able to solve now," Bartl says. "For certain problems, an optical computer could do in seconds what regular computers need years for."
Researchers also are seeking ideal photonic crystals to amplify light and thus make solar cells more efficient, to capture light that would catalyze chemical reactions, and to generate tiny laser beams that would serve as light sources on optical chips.
"Photonic crystals are a new type of optical materials that manipulate light in non-classic ways," Bartl says. Some colors of light can pass through a photonic crystal at various speeds, while other wavelengths are reflected as the crystal acts like a mirror.
Bartl says there are many proposals for how light could be manipulated and controlled in new ways by photonic crystals, "however we still lack the proper materials that would allow us to create ideal photonic crystals to manipulate visible light. A material like this doesn't exist artificially or synthetically."
The ideal photonic crystal -- dubbed the "champion" crystal -- was described by scientists elsewhere in 1990. They showed that the optimal photonic crystal -- one that could manipulate light most efficiently -- would have the same crystal structure as the lattice of carbon atoms in diamond. Diamonds cannot be used as photonic crystals because their atoms are packed too tightly together to manipulate visible light.
When made from an appropriate material, a diamond-like structure would create a large "photonic bandgap," meaning the crystalline structure prevents the propagation of light of a certain range of wavelengths. Materials with such bandgaps are necessary if researchers are to engineer optical circuits that can manipulate visible light.
On the Path of the Beetle: From BYU to Belgium and Brazil
The new study has its roots in Richey's science fair project on iridescence in biology when she was a student at Utah's Springville High School. Gardner's group at BYU was helping her at the same time Galusha was using an electron microscope there and learned of Richey's project.
Richey wanted to examine an iridescent beetle, but lacked a complete specimen. So the researchers ordered Brazil's Lamprocyphus augustus from a Belgian insect dealer.
The beetle's shiny, sparkling green color is produced by the crystal structure of its scales, not by any pigment, Bartl says. The scales are made of chitin, which forms the external skeleton, or exoskeleton, of most insects and is similar to fingernail material. The scales are affixed to the beetle's exoskeleton. Each measures 200 microns (millionths of a meter) long by 100 microns wide. A human hair is about 100 microns thick.
Green light -- which has a wavelength of about 500 to 550 nanometers, or billionths of a meter -- cannot penetrate the scales' crystal structure, which acts like mirrors to reflect the green light, making the beetle appear iridescent green.
Bartl says the beetle was interesting because it was iridescent regardless of the angle from which it was viewed -- unlike most iridescent objects -- and because a preliminary electron microscope examination showed its scales did not have the structure typical of artificial photonic crystals.
"The color and structure looked interesting," Bartl says. "The question was: What was the exact three-dimensional structure that produces these unique optical properties?"
The Utah team's study is the first to show that "just as atoms are arranged in diamond crystals, so is the chitin structure of beetle scales," he says.
Galusha determined the 3-D structure of the scales using a scanning electron microscope. He cut a cross section of a scale, and then took an electron microscope image of it. Then he used a focused ion beam -- sort of a tiny sandblaster that shoots a beam of gallium ions -- to shave off the exposed end of the scale, and then took another image, doing so repeatedly until he had images of 150 cross-sections from the same scale.
Then the researchers "stacked" the images together in a computer, and determined the crystal structure of the scale material: a diamond-like or "champion" architecture, but with building blocks of chitin and air instead of the carbon atoms in diamond.
Next, Galusha and Bartl used optical studies and theory to predict optical properties of the scales' structure. The prediction matched reality: green iridescence.
Many iridescent objects appear that way only when viewed at certain angles, but the beetle remains iridescent from any angle. Bartl says the way the beetle does that is an "ingenious engineering strategy" that approximates a technology for controlling the propagation of visible light.
A single beetle scale is not a continuous crystal, but includes some 200 pieces of chitin, each with the diamond-based crystal structure but each oriented a different direction. So each piece reflects a slightly different wavelength or shade of green.
"Each piece is too small to be seen individually by your eye, so what you see is a composite effect," with the beetle appearing green from any angle, Bartl explains.
Scientists don't know how the beetle uses its color, but "because it is an unnatural green, it's likely not for camouflage," Bartl says. "It could be to attract mates."
The study was funded by the National Science Foundation, American Chemical Society, the University of Utah and Brigham Young University.

Fausto Intilla - www.oloscience.com

Researchers teach 'Second Life' avatar to think

2008-05-19T12:02:00.000-07:00

Source:

http://www.lse.co.uk

TROY, N.Y. (AP) - Edd Hifeng barely merits a second glance in 'Second Life.' A steel-gray robot with lanky limbs and linebacker shoulders, he looks like a typical avatar in the popular virtual world.But Edd is different.His actions are animated not by a person at a keyboard but by a computer.
Edd is a creation of artificial intelligence, or AI, by researchers at Rensselaer Polytechnic Institute, who endowed him with a limited ability to converse and reason. It turns out 'Second Life' is more than a place where pixelated avatars chat, interact and fly about. It's also a frontier in AI research because it's a controllable environment where testing intelligent creations is easier.'It's a very inexpensive way to test out our technologies right now,' said Selmer Bringsjord, director of the Rensselaer Artificial Intelligence and Reasoning Laboratory.Bringsjord sees Edd as a forerunner to more sophisticated creations that could interact with people inside three-dimensional projections of settings like subway stops or city streets. He said the holographic illusions could be used to train emergency workers or solve mysteries.But first, a virtual reality check.Edd is not running rampant through the cyber streets of 'Second Life.' He goes only where Bringsjord and his graduate students place him for tests. He can answer questions like 'Where are you from?' but understands only English that has previously been translated into mathematical logic.'Second Life' is attractive to researchers in part because virtual reality is less messy than plain-old reality. Researchers don't have to worry about wind, rain or coffee spills.And virtual worlds can push along AI research without forcing scientists to solve the most difficult problems -- like, say, creating a virtual human -- right away, said Michael Mateas, a computer science professor at the University of California at Santa Cruz.Researching in virtual realities has become increasingly popular the past couple years, said Mateas, leader of the school's Expressive Intelligence Studio for AI and gaming.'It's a fantastic sweet spot -- not too simple, not too complicated, high cultural value,' he said.Bringsjord is careful to point out that the computations for Edd's mental feats have been done on workstations and are not sapping 'Second Life' servers. The calculations will soon be performed on a supercomputer at Rensselaer with support from research co-sponsor IBM Corp.Operators of 'Second Life' don't seem concerned about synthetic agents lurking in their world. John Lester, Boston operations manager for Linden Lab, said the San Francisco-based company sees
a 'fascinating' opportunity for AI to evolve.
'I think the real future for this is when people take these AI-controlled avatars and let them free in 'Second Life,'' Lester said, ' ... let them randomly walk the grid.'That is years off by most experts' estimations. Edd's most sophisticated cognitive feat so far -- played out in 'Second Life' and posted on the Web -- involves him witnessing a gun being switched from one briefcase to another. Edd was able to infer that another 'Second Life' character who left the room during the switch would incorrectly think the gun was still in the first suitcase.This ability to make inferences about the thoughts of others is significant for an AI agent, though it puts Edd on par with a 4-year-old -- and the calculus required 'under the hood' to achieve this feat is mind-numbingly complex.A computer program smart enough to fool someone into thinking they're interacting with another person -- the traditional Holy Grail for AI researchers -- has been elusive. One huge problem is getting computers to understand concepts imparted in language, said Jeremy Bailenson, director of the Virtual Human Interaction Lab at Stanford University.AI agents do best in tightly controlled environments: Think of automated phone programs that recognize your responses when you say 'operator' or 'repair.'Bringsjord sees 'Second Life' as a way station. He eventually wants to create other environments where more sophisticated creations could display courage or deceive people, which would be the first step in developing technology to detect deception.The avatars could be projected at RPI's $145 million Experimental Media and Performing Arts Center, opening in October, which will include spaces for holographic projections. Officials call them 'holodecks' in homage to the virtual reality room on the 'Star Trek' television series.That sort of visual fidelity is many years down the line, just like complex AI. John Kolb, RPI's chief information officer, said the best three-dimensional effects still require viewers to wear special light-polarizing glasses.'If you want to do texture mapping on a wall for instance, that's easy. We can do that today,' Kolb said. 'If you want to start to build cognitive abilities into avatars, well, that's going to take a bit more work.'

Fausto Intilla - www.oloscience.com

Braille Converter Bridges The Information Gap

2008-05-12T11:08:00.000-07:00

Source:

http://www.sciencedaily.com/releases/2008/05/080508174310.htm

ScienceDaily (May 12, 2008) — A free, e-mail-based service that translates text into Braille and audio recordings is helping to bridge the information gap for blind and visually impaired people, giving them quick and easy access to books, news articles and web pages.
Developed by European researchers, the RoboBraille service offers a unique solution to the problem of converting text into Braille and audio without the need for users to operate complicated software.
“We started working in this field 20 years ago, developing software to translate text into Braille, but we discovered that users found the programs difficult to use – we therefore searched for a simpler solution,” explains project coordinator Lars Ballieu Christensen, who also works for Synscenter Refsnaes, a Danish centre for visually impaired children.
The result of the EU-funded project was RoboBraille, a service that requires no more skill with a computer than the ability to send an e-mail.
Users simply attach a text they want to translate in one of several recognised formats, from plain text and Word documents to HTML and XML. They then e-mail the text to the service’s server. Software agents then automatically begin the process of translating the text into Braille or converting it into an audio recording through a text-to-speech engine.
“The type of output and the language depends on the e-mail address the user sends the text to,” Christensen says. “A document sent to .org would be converted into spoken British English while a text sent to .org would be translated from Portuguese into six-dot Braille.”
The user then receives the translation back by e-mail, which can be read on a Braille printer or on a tactile display, a device connected to the computer with a series of pins that are raised or lowered to represent Braille characters.
RoboBraille can currently translate text written in English, Danish, Italian, Greek and Portuguese into Braille and speech. The service can also handle text-to-speech conversions in French and Lithuanian.
Christensen notes that the RoboBraille partners are constantly working on adding new languages to the service and plan to start providing Braille and audio translations for Russian, Spanish, German and Arabic. They are also working on making the service compatible with PDF documents and text scanned from images.
Up to 14,000 translations a day
At present, the service translates an average of 500 documents a day, although it could handle as many as 14,000. RoboBraille can return a simple text in Braille in under a minute while taking as long as 10 hours to provide an audio recording of a book.
As of January, the RoboBraille system had carried out 250,000 translations since it first went online.
The team have won widespread recognition for their work, receiving the 2007 Social Contribution Award from the British Computer Society in December while in April they were awarded the 2008 award for technological innovation from Milan-based Well-Tech.
“We initially started offering the service only in Denmark but to make it viable commercially we needed to broaden our horizons. Hence the eTen project which allowed us to involve other organisations across Europe in developing and expanding the service, not only geographically but also in terms of users,” Christensen says.
In addition to the blind and visually impaired, the service can also help dyslexics, people with reading difficulties and the illiterate. The project partners plan to continue to offer the service for free to such users and other individuals, while in parallel developing commercial services for companies and public institutions.
“Pharmaceutical companies in Europe will soon be required to ensure all medicine packaging is labelled in Braille and we are currently working with three big firms to provide that service,” Christensen explains. “Banks and insurance companies are also interested in using it to provide statements in Braille as too is the Danish tax office. In Italy there is interest in using it in the tourism sector.”
The RoboBraille team, which recently received an €1.1 million grant over four years from the Danish government, expect the service to be profitable within four or five years.
And although they are not actively seeking investors, they are interested in partnerships with organisations interested in collaborating on specific social projects.
RoboBraille was funded under the EU's eTEN programme for market validation and implementation.

Fausto Intilla - www.oloscience.com

Quantum Cryptography Cracked?

2008-05-12T08:55:00.000-07:00

Source:

http://www.spectrum.ieee.org/apr08/6203

29 April 2008—Quantum cryptography, touted by scientists as the ultimate unbreakable code, may turn out to be susceptible to eavesdropping after all when implemented practically, according to a Swedish duo.
“Quantum codes are supposed to guarantee 100 percent security,” says Jan-Ake Larsson, associate professor of mathematics at Linkoeping University, in Sweden. “If they don't live up to that promise, that's a problem.”
Larsson and his former graduate student Jorgen Cederlof, who now works for Google, say they have spotted a flaw in practical quantum codes. Their report on this flaw and a patch for the problem appear in the April issue of the IEEE Transactions on Information Theory.
The most secure codes currently in use rely on public-key cryptography, whose security stems from the fact that computers today cannot factor very large numbers within a useful time period. However, in theory, given sufficiently powerful computers, these codes can be cracked.
Quantum cryptography, in contrast, is supposed to be unbreakable, even in theory, because its security is based on a fundamental tenet of quantum mechanics. It turns out that the very act of measurement in quantum mechanics changes the nature of the quantum system being observed. Thus, if an eavesdropper listens in on a quantum message between two parties, he or she changes the message in a way that is detectable. Through a multistep process, quantum encryption systems—and there are at least three on the market now—use the security of quantum mechanics to generate cryptographic keys. These quantum keys are ciphers used to encode and decode messages.
The process of key generation, though based on quantum physics, also requires exchanging some information on a regular “classical” channel. Eavesdropping on the classical channel cannot be detected. One of the final steps in setting up a quantum key is to authenticate the communicating parties—determining that Bob is really talking to Alice, not some eavesdropper.
If there is no authentication, Alice and Bob will be open to a “man in the middle” attack, as it is termed by code breakers. The attack would work like this, Cederlof explains: “Now Eve comes along, buys a couple of [quantum encryption] devices identical to the ones Alice and Bob have, cuts the cables between Alice and Bob, and connects her devices at both ends. Now Alice will think she is talking to Bob, but in reality she is talking to Eve. Eve just acts as Bob would have, and after a while Alice and Eve have created a shared secret key. The same thing happens between Eve and Bob. When Alice tries to send an encrypted message to Bob, she will encrypt it with a key known only to Eve (but which Alice thinks only Bob knows). Eve intercepts the message, decrypts it, reads it, encrypts it with the key she shares with Bob, and sends it to Bob. Alice and Bob never suspect anything.”
The way around this is to communicate classically and make sure Alice is really talking to Bob. But that is exactly where the vulnerability lies.
“To our surprise, the authentication was not secure,” says Larsson. He and Cederlof say that it is difficult to eavesdrop, but the possibility does exist. In their paper they suggest a patch. “The modification we propose is basically an extra exchange of a small amount of random bits on the classical channel,” says Larsson.
According to Tassos Nakassis a computer scientist at the National Institute of Standards and Technology (NIST), in Gaithersburg, Md., the error may have originated because quantum cryptography is an emerging interdisciplinary field that combines advanced quantum physics with traditional code making. Authentication and its weaknesses may have gotten lost in the conversation between quantum physicists and classical cryptographers.
The Swedes went looking in just the right place for a vulnerability, according to Bruce Schneier, an expert in cryptography and chief technology officer at BT Counterpane, in Santa Clara, Calif. “Authentication has always been a problem with quantum crypto,” he says.
Audrius Berzanskis, chief operating officer at the quantum cryptography systems firm MagiQ Technologies, in New York City, claims his firm's systems are immune to this kind of attack, because they are overly conservative with respect to how they treat errors in the quantum channel—whether or not the errors are caused by an eavesdropper. This conservatism comes at the cost of the rate at which quantum keys are generated. And Berzanskis adds that Larsson and Cederlof's patch might allow the key rate to increase. Experts from outside quantum cryptography companies agree that the vulnerability is real, but most think it would be impractical to exploit.
“This is an interesting issue and worthy of the awareness of the community,” says physicist Joshua Bienfang, who works on quantum cryptography at NIST. But he notes that Larsson and Cederlof correctly emphasize that the attack relies on Eve capitalizing on opportunities that occur with very low probability. In their worst-case scenario, with a computationally omnipotent Eve, they estimate it would take something on the order of nine months to break the system. And he says that the patch offered should “firmly shut the door on this type of attack.”
Norbert Lutkenhaus, a physicist at the Institute for Quantum Computing, in Canada, summed it up. “Practically, I don't think it is a threat of any kind,” he says. “But it is good to know about the vulnerability.”

Fausto Intilla - www.oloscience.com

Location Spoofing Possible With WiFi Devices: Positioning System Used By IPhone/iPod Breached

2008-04-16T10:21:00.001-07:00

Source:
http://www.sciencedaily.com/releases/2008/04/080414145659.htm

ScienceDaily (Apr. 16, 2008) — Apple iPhone and iPod (touch) support a new self-localization feature that uses known locations of wireless access points as well as the device's own ability to detect access points. Now researchers at ETH Zurich/Swiss Federal Institute of Technology have demonstrated that positions displayed by the devices using this system can be falsified, making the use of this self-localization system unsuitable in a number of security- and safety-critical applications.
In January, Skyhook Wireless Inc. announced that Apple would use Skyhook's WiFi Positioning System (WPS) for its popular Map applications. The WPS database contains information on access points throughout the world. Skyhook itself provides most of the data in the database, with users contributing via direct entries to the database, and requests for localization. ETH Zurich Professor Srdjan Capkun of the Department of Computer Science and his team of researchers analysed the security of Skyhook's positioning system. The team's results demonstrate the vulnerability of Skyhook's and similar public WLAN positioning systems to location spoofing attacks.Impersonation and eliminationWhen an Apple iPod or iPhone wants to find its position, it detects its neighbouring access points, and sends this information to Skyhook servers. The servers then return the access point locations to the device. Based on this data, the device computes its location. To attack this localization process, Professor Capkun's team decided to use a dual approach. First, access points from a known remote location were impersonated. Second, signals sent by access points in the vicinity were eliminated by jamming. These actions created the illusion in localized devices that their locations were different from their actual physical locations.Simple falsificationSkyhook's WPS works by requiring a device to report the Media Access Control (MAC) addresses that it detects. However, since MAC addresses can be forged by rogue access points, they can be easily impersonated. Furthermore, access point signals can be jammed and signals from access points in the vicinity of the device can thus be eliminated. These two actions make location spoofing attacks possible.Compromised usageProfessor Capkun explained that by demonstrating these attacks, the team hoped to point out the limitations, despite guarantees, of public WLAN-based localization services as well as of applications for such services. He said "Given the relative simplicity of the performed attacks, it is clear that the use of WLAN-based public localization systems, such as Skyhook's WPS, should be restricted in security and safety-critical applications."Adapted from materials provided by ETH Zurich/Swiss Federal Institute of Technology, via EurekAlert!, a service of AAAS.

Fausto Intilla - www.oloscience.com

Getting Wired For Terahertz Computing

2008-04-15T21:41:00.001-07:00

Source:

http://www.sciencedaily.com/releases/2008/04/080414232716.htm

ScienceDaily (Apr. 15, 2008) — University of Utah engineers took an early step toward building superfast computers that run on far-infrared light instead of electricity: They made the equivalent of wires that carried and bent this form of light, also known as terahertz radiation, which is the last unexploited portion of the electromagnetic spectrum.

"We have taken a first step to making circuits that can harness or guide terahertz radiation," says Ajay Nahata, study leader and associate professor of electrical and computer engineering. "Eventually -- in a minimum of 10 years -- this will allow the development of superfast circuits, computers and communications."
Electricity is carried through metal wires. Light used for communication is transmitted through fiberoptic cables and split into different colors or "channels" of information using devices called waveguides. In a study to be published April 18 in the online journal Optics Express, Nahata and colleagues report they designed stainless steel foil sheets with patterns of perforations that successfully served as wire-like waveguides to transmit, bend, split or combine terahertz radiation.
"A waveguide is something that allows you to transport electromagnetic radiation from one point to another point, or distribute it across a circuit," Nahata says.
If terahertz radiation is to be used in computing and communication, it not only must be transmitted from one device to another, "but you have to process it," he adds. "This is where terahertz circuits are important. The long-term goal is to develop capabilities to create circuits that run faster than modern-day electronic circuits so we can have faster computers and faster data transfer via the Internet."
Nahata conducted the study with two doctoral students in electrical and computer engineering: Wenqi Zhu and Amit Agrawal.
Developing Terahertz Technology
The electromagnetic spectrum, which ranges from high to low frequencies (or short to long wavelengths), includes: gamma rays, X-rays, ultraviolet light, visible light (violet, blue, green, yellow, orange and red), infrared light (including radiant heat and terahertz radiation), microwaves, FM radio waves, television, short wave and AM radio.
Fiberoptic phone and data lines now use near-infrared light and some visible light. The only part of the spectrum not now used for communications or other practical purposes is terahertz-frequency or far-infrared radiation -- also nicknamed T-rays -- located on the spectrum between mid-infrared and microwaves.
With so much of the spectrum clogged by existing communications, engineers would like to harness terahertz frequencies for communication, much faster computing and even for anti-terrorism scanners and sensors able to detect biological, chemical or other weapons. Nahata says the new study is relevant mainly to computers that would use terahertz radiation to run at speeds much faster than current computers.
In March 2007, Nahata, Agrawal and others published a study in the journal Nature showing it was possible to control a signal of terahertz radiation using thin stainless steel foils perforated with round holes arranged in semi-regular patterns.
This February, British researchers reported they used computer simulations and some experiments to show that indentations punched across an entire sheet of copper-clad polymer could hold terahertz radiation close to the sheet's surface. That led them to conclude the far-infrared light could be guided along such a material's surface.
But the London researchers did not actually manipulate the direction the terahertz radiation moved, such as by bending or splitting it.
"We have demonstrated the ability to do this, which is a necessary requirement for making terahertz guided-wave circuits," Nahata says.
Circuits: From Electrical to Optical to Terahertz
Wires act as waveguides for electricity. Wires connect active devices such as transistors, which switch or adjust the electric signal. That is the basis for how computers work today. An electronic integrated circuit is a computer processor made of wires, transistors, resistors and capacitors on a semiconductor chip made of silicon.
In optical communications, the waveguides carry laser-generated light in fiberoptic cables and lines etched or deposited on an insulator or semiconductor surface. Nahata says photonic integrated circuits now are used for phone and Internet communications, mainly for combining or "multiplexing" different colors or channels of light entering a fiber-optic cable and separating or "demultiplexing" the different wavelengths exiting the cable.
"Electronic circuits today work at gigahertz frequencies -- billions of cycles per second. Electronic devices like a computer chip can operate at gigahertz," Nahata says. "What people would like to do is develop capabilities to transport and manipulate data at terahertz frequencies [trillions of hertz.] It's a speed issue. People want to be able to transfer data at higher speeds. People would like to download a movie in a few seconds."
"In this study, we've demonstrated the first step toward making circuits that use terahertz radiation and ultimately might work at terahertz speeds," or a thousand times faster than today's gigahertz-speed computers, Nahata says.
Channeling, Bending, Splitting and Coupling T-Rays
"People have been working on terahertz waveguides for a decade," he says. "We've shown how to make these waveguides on a flat surface so that you can make circuits just like electronic circuits on silicon chips."
The researchers used pieces of stainless steel foil about 4 inches long, 1 inch wide and 625 microns thick, or 6.25 times the thickness of a human hair. They perforated the metal with rectangular holes, each measuring 500 microns (five human hair widths) by 50 microns (a half a hair width). The rectangular holes were arranged side by side in three different patterns to form "wires" for terahertz radiation:
One line of rectangles that served as a "wire" and carried terahertz radiation.
A line that becomes two lines -- like the letter Y -- to split the far-infrared light, similar to a splitter used to route a home cable TV signal to separate television sets.
Two lines that curve close to each other in the middle -- like an X where the two lines come close but don't touch -- so the radiation could be "coupled," or moved from one line or "wire" to another.
The straight pattern successfully carried terahertz radiation in a straight line. The other two patterns "changed the direction the terahertz radiation was moving" by splitting it or coupling it, Nahata says. The study showed the terahertz radiation was closely confined both vertically (within 1.69 millimeters of the foil's surface) and horizontally (within 2 millimeters of the pattern of rectangles as it moved over them).
"All we've done is made the wires" for terahertz circuits, Nahata says. "Now the issue is how do we make devices [such as switches, transistors and modulators] at terahertz frequencies?"
When terahertz radiation is fed into the stainless steel waveguides, it spans a range of frequencies. One frequency is guided across the steel surface. That frequency is determined by the size of perforations in the foil. The engineers chose a frequency they could generate and measure: about 0.3 terahertz, or 300 gigahertz. Terahertz radiation is defined as ranging from 0.1 terahertz (or 100 gigahertz) to 10 terahertz.
The design of the waveguide means that it carries terahertz radiation in the form of surface plasma waves -- also known as plasmons or plasmon polaritons -- which are analogous to electrons in electrical devices or photons of light in optical devices. The surface plasma waves are waves of electromagnetic radiation at a terahertz frequency that are bound to the surface of the steel foil because they are interacting with moving electrons in the metal, Nahata says.
Adapted from materials provided by University of Utah, via EurekAlert!, a service of AAAS.

Fausto Intilla

www.oloscience.com

Supercomputers Simulating As Close As Possible To Reality

2008-04-14T10:04:00.000-07:00

Source: http://www.sciencedaily.com/releases/2008/04/080411150948.htm

ScienceDaily (Apr. 14, 2008) — Supercomputers simulate products and manufacturing processes with-in minutes. In the Computer Aided Robust Design CAROD project, Fraunhofer researchers are developing new methods and software that significantly improve the quality of the virtual components.

Trucks drive thousands of kilometers through Europe every month, taking oranges from Greece to Scandinavia, delivering Spanish vegetables to German wholesalers, and collecting milk from farms in the region to take it to central dairies. To make sure the tires, wheel rims and other parts will survive the many kilometers without breaking down, the manufacturers test prototypes in test rigs to discover their service life.
Such a test often lasts several weeks, yet it can be rendered useless by malfunctions, such as when bearings or sensors wear out. In the Computer Aided Robust Design (CAROD) project, research scientists from seven Fraunhofer Institutes are devising methods with which malfunctions of this nature can be simulated ahead of time. The researchers are using the results to develop sturdy test rigs for life-cycle tests.
“Today the development and testing of prototypes – be they entire cars or individual components – takes place mainly in the computer,” says Andreas Burblies, spokesman for the Fraunhofer Numerical Simulation Alliance. But this simulation only reflects reality to a limited extent. “As a rule, there are no parts or manufacturing processes in which all product or process properties are identical.
But the developers always get the same simulation results if they enter the same pa-rameters.” This is where the researchers come in with their Computer Aided Robust Design. The goal is to develop new methods and software that makes it possible to factor the real deviations into the simulation calculations. In this way mechatronic systems, crash tests or laser processing methods can be made even less vulnerable to errors and variations.
One of the pillars of the new technology is the Taguchi method. The Japanese scientist Genichi Taguchi developed a method of making products, processes and systems resistant to interference. It is already applied in quality management, enabling the industry to achieve the optimum product quality. The task of CAROD is to improve quality by taking faults, variations and breakdowns into account during the virtual design phase.
“We are aiming to get as close to the natural manufacturing conditions as possible with our simulations,” says Dr. Tanja Clees, project manager at the Fraunhofer Institute for Algorithms and Scientific Computing SCAI in Sankt Augustin. Right now it is still early days for the new simulation software, but the experts are confident of achieving good results very soon. CAROD can be seen at the Hannover Messe in Germany from April 21 through 25.
Adapted from materials provided by Fraunhofer-Gesellschaft.

Fausto Intilla - www.oloscience.com

Next-generation RAM: Remembering The Future

2007-12-23T09:53:00.000-08:00

Source:

http://www.sciencedaily.com/releases/2007/12/071221174912.htm

ScienceDaily (Dec. 23, 2007) — As electronics designers cram more and more components onto each chip, current technologies for making random-access memory (RAM) are running out of room. European researchers have a strong position in a new technology known as resistive RAM (RRAM) that could soon be replacing flash RAM in USB drives and other portable gadgets.
On the ‘semiconductor road map’ setting out the future of the microchip industry, current memory technologies are nearing the end of the road. Future computers and electronic gadgets will need memory chips that are smaller, faster and cheaper than those of today –and that means going back to basics.
Today’s random-access memory (RAM) falls mainly into three classes: static RAM (SRAM), dynamic RAM (DRAM), and flash memory. Each has its advantages and drawbacks; flash, for instance, is the only one to retain data when the power is switched off, but is slower.
According to Professor Paul Heremans of the University of Leuven in Belgium, circuit designers looking for the best performance often have to combine several memory types on the same chip. This adds complexity and cost.
A more serious issue is scalability. As designers pack more components onto each chip, the width of the smallest features is shrinking, from 130 nanometers (nm) in 2000 to 45 nm today. Existing memory technologies are good for several more generations, Heremans says, but are unlikely to make the transition to 22 nm (scheduled for 2011) or 16 nm (2018).
So we need new memory technologies that can be made smaller than those of today, as well as preferably being faster, power saving and non-volatile. The runners in the global memory technology race form a veritable alphabet soup of acronyms including MRAM, RRAM, FeRAM, Z-RAM, SONOS, and nano-RAM.
No universal solution
Early in 2004, Heremans became the coordinator of an EU-supported project that included two of Europe’s biggest semiconductor manufacturers: STMicroelectronics of Italy and Philips of the Netherlands. Heremans’ own institution, IMEC, is a leading independent research centre in microelectronics and nanotechnology. The Polish Academy of Sciences was the fourth partner in the project.
The Nosce Memorias (Latin for ‘Know your memories’) project started out to develop a universal memory that was fast, non-volatile, and flexible enough to replace several existing types. It had to be compatible with CMOS, the current standard chip manufacturing technology, and scalable for several generations below 45 nm.
As the research progressed it became clear that a universal memory would require too many compromises, notes Heremans. Instead, the team targeted a non-volatile memory that would have better performance and scalability than current flash technology.
Flash memory, used for USB ‘key-ring’ drives and digital cameras, can store data for years using transistors to retain electric charge. The technology can be scaled down for several more generations, Heremans says, but sooner or later it will reach a limit. Flash memory is also slow to read and needs high voltages to operate.
Exploring resistive memory
The hopes of Nosce Memorias rested on a technology known as resistive RAM (RRAM). Instead of storing information in transistors (flash memory) or capacitors (DRAM), RRAM relies on the ability to alter the electrical resistance of certain materials by applying an external voltage or current. RRAM is non-volatile, and its simple structure is ideal for future generations of CMOS chips.
The project looked at three types of RRAM. The first, known as a ferroelectric Schottky diode, was abandoned when the researchers realised they were unlikely to be able to create starting materials with the required properties.
The second technology studied was a metal-organic charge-transfer material called CuTCNQ. Although CuTCNQ has been known for around 20 years, its precise mode of operation was unclear, Heremans says. The team learned a lot about how this material works, developed new ways of preparing it, and succeeded in creating the smallest organic memory cells ever made, at 100 nm across.
Lastly, the team looked at RRAM based on organic semiconductors. Because this work did not start until halfway through the project, the results did not reach the same level as those for CuTCNQ, but significant progress was made.
EMMA carries on
When Nosce Memorias ended in March 2007, plenty of work remained to be done to create a workable RRAM.
The challenge was taken up by EMMA (Emerging Materials for Mass-storage Architectures), another EU-supported project that runs until September 2009. Like Nosce Memorias, EMMA is coordinated by IMEC and has STMicroelectronics as a member, though the other partners are different.
EMMA is working on the CuTCNQ developed by Nosce Memorias, as well as on metal oxides. For CuTCNQ, Heremans explains, the goals are to make the material more durable through better control of the switching mechanism, now that this is understood.
Extended working life is also important for the polymer semiconductors pioneered by Nosce Memorias. Low-cost polymer memory could be important in RFID tags (also called ORFID) for the remote identification of goods, equipment and people.
Adapted from materials provided by ICT Results.

Fausto Intilla
www.oloscience.com

New Computer Program Automates Chip Debugging

2007-11-06T22:39:00.000-08:00

Source:

http://www.sciencedaily.com/releases/2007/11/071105103927.htm

ScienceDaily (Nov. 6, 2007) — Fixing design bugs and wrong wire connections in computer chips after they've been fabricated in silicon is a tedious, trial-and-error process that often costs companies millions of dollars and months of time-to-market.
Engineering researchers at the University of Michigan say it doesn't have to be that way. They've developed a new technology to automate "post-silicon debugging."
"Today's silicon technology has reached such levels of small-scale fabrication and of sheer complexity that it is almost impossible to produce computer chips that work correctly under all scenarios," said Valeria Bertacco, assistant professor of electrical engineering and computer science and co-investigator in the new technology. "Almost all manufacturers must produce several prototypes of a given design before they attain a working chip."
FogClear, as the new method is called, uses puzzle-solving search algorithms to diagnose problems early on and automatically adjust the blueprint for the chip. It reduces parts of the process from days to hours.
"Practically all complicated chips have bugs and finding all bugs is intractable," said Igor Markov, associate professor of computer science and electrical engineering and another of FogClear's developers. "It's a paradox. Today, manufacturers are producing chips that must work for almost all applications, from e-mail to chess, but they cannot be validated for every possible condition. It's physically impossible."
In the current system, a chip design is first validated in simulations. Then a draft is cast in silicon, and this first prototype undergoes additional verification with more realistic applications. If a bug is detected at this stage, an engineer must narrow down the cause of the problem and then craft a fix that does not disrupt the delicate balance of all other components of the system. This can take several days. Engineers then produce new prototypes incorporating all the fixes. This process repeats until they arrive at a prototype that is free of bugs. For modern chips, the process of making sure a chip is free of bugs takes as much time as production.
"Bugs found post-silicon are often very difficult to diagnose and repair because it is difficult to monitor and control the signals that are buried inside a silicon die, or chip. Up until now engineers have handled post-silicon debugging more as an art than a science," said Kai-Hui Chang, a recent doctoral graduate who will present a paper on FogClear at the upcoming International Conference on Computer-Aided Design.
FogClear automates this debugging process. The computer-aided design tool can catch subtle errors that several months of simulations would still miss. Some bugs might take days or weeks before causing any miscomputation, and they might only do so under very rare circumstances, such as operating at high temperature. The new application searches for and finds the simplest way to fix a bug, the one that has the least impact on the working parts of the chip. The solution usually requires reconnecting certain wires, and does not affect transistors.
Chang, who received his doctorate in electrical engineering and computer science from U-M in August, will present Nov. 6 at the International Conference on Computer-Aided Design in San Jose, California. The paper is titled "Automating Post-Silicon Debugging and Repair." Markov and Bertacco are co-authors with Chang.
Adapted from materials provided by University of Michigan.

Fausto Intilla
www.oloscience.com

Computers With 'Common Sense'

2007-10-19T09:45:00.000-07:00

Source:

http://www.sciencedaily.com/releases/2007/10/071017174328.htm

ScienceDaily (Oct. 18, 2007) — Using a little-known Google Labs widget, computer scientists from UC San Diego and UCLA have brought common sense to an automated image labeling system. This common sense is the ability to use context to help identify objects in photographs.

For example, if a conventional automated object identifier has labeled a person, a tennis racket, a tennis court and a lemon in a photo, the new post-processing context check will re-label the lemon as a tennis ball.
“We think our paper is the first to bring external semantic context to the problem of object recognition,” said computer science professor Serge Belongie from UC San Diego.
The researchers show that the Google Labs tool called Google Sets can be used to provide external contextual information to automated object identifiers.
Google Sets generates lists of related items or objects from just a few examples. If you type in John, Paul and George, it will return the words Ringo, Beatles and John Lennon. If you type “neon” and “argon” it will give you the rest of the noble gasses.
“In some ways, Google Sets is a proxy for common sense. In our paper, we showed that you can use this common sense to provide contextual information that improves the accuracy of automated image labeling systems,” said Belongie.
The image labeling system is a three step process. First, an automated system splits the image up into different regions through the process of image segmentation. In the photo above, image segmentation separates the person, the court, the racket and the yellow sphere.
Next, an automated system provides a ranked list of probable labels for each of these image regions.
Finally, the system adds a dose of context by processing all the different possible combinations of labels within the image and maximizing the contextual agreement among the labeled objects within each picture.
It is during this step that Google Sets can be used as a source of context that helps the system turn a lemon into a tennis ball. In this case, these “semantic context constraints” helped the system disambiguate between visually similar objects.
In another example, the researchers show that an object originally labeled as a cow is (correctly) re-labeled as a boat when the other objects in the image – sky, tree, building and water – are considered during the post-processing context step. In this case, the semantic context constraints helped to correct an entirely wrong image label. The context information came from the co-occurrence of object labels in the training sets rather than from Google Sets.
The computer scientists also highlight other advances they bring to automated object identification. First, instead of doing just one image segmentation, the researchers generated a collection of image segmentations and put together a shortlist of stable image segmentations. This increases the accuracy of the segmentation process and provides an implicit shape description for each of the image regions.
Second, the researchers ran their object categorization model on each of the segmentations, rather than on individual pixels. This dramatically reduced the computational demands on the object categorization model.
In the two sets of images that the researchers tested, the categorization results improved considerably with inclusion of context. For one image dataset, the average categorization accuracy increased more than 10 percent using the semantic context provided by Google Sets. In a second dataset, the average categorization accuracy improved by about 2 percent using the semantic context provided by Google Sets. The improvements were higher when the researchers gleaned context information from data on co-occurrence of object labels in the training data set for the object identifier.
Right now, the researchers are exploring ways to extend context beyond the presence of objects in the same image. For example, they want to make explicit use of absolute and relative geometric relationships between objects in an image – such as “above” or “inside” relationships. This would mean that if a person were sitting on top of an animal, the system would consider the animal to be more likely a horse than a dog.
Reference: “Objects in Context,” by Andrew Rabinovich, Carolina Galleguillos, Eric Wiewiora and Serge Belongie from the Department of Computer Science and Engineering at the UCSD Jacobs School of Engineering. Andrea Vedaldi from the Department of Computer Science, UCLA.
The paper will be presented on Thursday 18 October 2007 at ICCV 2007 – the 11th IEEE International Conference on Computer Vision in Rio de Janeiro, Brazil.
Funders: National Science Foundation, Afred P. Sloan Research Fellowship, Air Force Office of Scientific Research, Office of Naval Research.
Adapted from materials provided by University of California - San Diego.

Fausto Intilla

www.oloscience.com

Thwarting The Growth Of Internet Black Markets

2007-10-16T23:30:00.000-07:00

Source:

http://www.sciencedaily.com/releases/2007/10/071015102827.htm

Science Daily — Carnegie Mellon University's Adrian Perrig and Jason Franklin, working in conjunction with Vern Paxson of the International Computer Science Institute and Stefan Savage of the University of California, San Diego, have designed new computer tools to better understand and potentially thwart the growth of Internet black markets, where attackers use well-developed business practices to hawk viruses, stolen data and attack services.
"These troublesome entrepreneurs even offer tech support and free updates for their malicious creations that run the gamut from denial of service attacks designed to overwhelm Web sites and servers to data stealing Trojan viruses," said Perrig, an associate professor of electrical and computer engineering and engineering and public policy.
In order to understand the millions of lines of data derived from monitoring the underground markets for more than seven months, Carnegie Mellon researchers developed automated techniques to measure and catalogue the activities of the shadowy online crooks who profit from spewed spam, virus-laden PCs and identity theft. The researchers estimate that the total value of the illegal materials available for sale in the seven-month period could total more than $37 million.
"Our research monitoring found that more than 80,000 potential credit card numbers were available through these illicit underground web economies," said Franklin, a Ph.D. student in computer science. However, the researchers warned that because checking the validity of the card numbers was not possible without credit card company assistance, the cards seen may not have been valid when they were observed.
Whatever the purchases, a buyer will typically contact the black market vendor privately using email, or in some cases, a private instant message. Money generally changes hands through non-bank payment services such as e-gold, making the criminals difficult to track.
To stem the flow of stolen credit cards and identity data, Carnegie Mellon researchers proposed two technical approaches to reduce the number of successful market transactions, including a slander attack and another technique, which were aimed at undercutting the cyber-crooks verification or reputation system.
"Just like you need to verify that individuals are honest on E-bay, online criminals need to verify that they are dealing with 'honest' criminals," Franklin said.
In a slander attack, an attacker eliminates the verified status of a buyer or seller through false defamation. "By eliminating the verified status of the honest individuals, an attacker establishes a lemon market where buyers are unable to distinguish the quality of the goods or services," Franklin said.
The researchers also propose to undercut the burgeoning black market activity by creating a deceptive sales environment.
Perrig's team developed a technique to establish fake verified-status identities that are difficult to distinguish from other-verified status sellers making it hard for buyers to identify the honest verified-status sellers from dishonest verified-status sellers.
"So, when the unwary buyer tries to collect the goods and services promised, the seller fails to provide the goods and services. Such behavior is known as 'ripping.' And it is the goal of all black market site's verification systems to minimize such behavior," said Franklin.
There have been successful takedowns against known black market sites, such as the U.S. Secret Service-run Operation Firewall three years ago. That operation against the notorious Shadowcrew resulted in 28 arrests around the globe, Carnegie Mellon researchers reported.
"The scary thing about all this is that you do not have to be in the know to find black markets, they are easy to find, easy to join and just a mouse click away," Franklin said.
"We believe these black markets are growing, so we will have even more incidents to monitor and study in the future," Perrig said.
That growth is also reflected in the latest Computer Security Institute (CSI) Computer Crime and Security Survey that shows average cyber-losses more than doubled after a five-year decline. The 2007 CSI survey reported that U.S. companies on average lost more than $300,000 to cyber crooks compared to $168,000 last year.
Note: This story has been adapted from material provided by Carnegie Mellon University.

Fausto Intilla
www.oloscience.com

Computer Security Can Double As Help For The Blind

2007-10-16T23:26:00.000-07:00

Source:

http://www.sciencedaily.com/releases/2007/10/071015093548.htm

Science Daily — Before you can post a comment to most blogs, you have to type in a series of distorted letters and numbers (a CAPTCHA) to prove that you are a person and not a computer attempting to add comment spam to the blog.

What if -- instead of wasting your time and energy typing something meaningless like SGO9DXG -- you could label an image or perform some other quick task that will help someone who is visually impaired do their grocery shopping?
In a position paper presented at Interactive Computer Vision (ICV) 2007 on October 15 in Rio de Janeiro, computer scientists from UC San Diego led by professor Serge Belongie outline a grid system that would allow CAPTCHAs to be used for this purpose -- and an endless number of other good causes.
"One of the application areas for my research is assistive technologyfor the blind. For example, there is an enormous amount of data that needs to be labeled for our grocery shopping aid to work. We are developing a wearable computer with a camera that can lead a visually impaired user to a desired product in a grocery store by analyzing the video stream. Our paper describes a way that people who are looking to prove that they are humans and not computers can help label still shots from video streams in real time," said Belongie.
The researchers call their system a "Soylent grid" which is a reference to the 1973 film Soylent Green (see more on this reference at the end of the article).
"The degree to which human beings could participate in the system (as remote sighted guides) ranges from none at all to virtually unlimited. If no human user is involved in the loop, only computer vision algorithms solve the identification problem. But in principle, if there were an unlimited number of humans in the loop, all the video frames could be submitted to a SOYLENT GRID, be solved immediately and sent back to the device to guide the user," the authors write in their paper.
From the front end, users who want to post a comment on a blog would be asked to perform a variety of tasks, instead of typing in a string of misshapen letters and numbers.
"You might be asked to click on the peanut butter jar or click the Cheetos bag in an image," said Belongie. "This would be one of the so called 'Where's Waldo' object detection tasks."
The task list also includes "Name that Thing" (object recognition), "Trace This" (image segmentation) and "Hot or Not" (choosing visually pleasing images).
"Our research on the personal shopper for the visually impaired -- called Grozi -- is a big motivation for this project. When we started the Grozi project, one of the students, Michele Merler -- who is now working on a Ph.D. at Columbia University -- captured 45 minutes of video footage from the campus grocery store and then endured weeks of manually intensive labor, drawing bounding boxes and identifying the 120 products we focused on. This is work the soylent grid could do," said Belongie.
From the back end, researchers and others who need images labeled would interact with clients (like a blog hosting company) that need to take advantage of the CAPTCHA and spam filtering capabilities of the grid.
"Getting this done is going to take an innovative collaboration between academia and industry. Calit2 could be uniquely instrumental in this project," said Belongie. "Right now we are working on a proposal that will outline exactly what we need -- access to X number of CAPTCHA requests in one week, for example. With this, we'll do a case study and demonstrate just how much data can be labeled with 99 percent reliability through the soylent grid. I'm hoping for people to say, 'Wow, I didn't know that kind of computation was available.'"
This work incorporates recent work from a variety of researchers, including computer scientist Luis von Ahn from Carnegie Mellon University. His reCAPTCHA project uses CAPTCHAs to digitize books.
Soylent Grid?
The researchers call their system a "Soylent grid" and titled their paper "Soylent Grid: it's Made of People! Both the grid name and paper name are references to the 1973 cult classic film Soylent Green, a dystopian science fiction film set in an overpopulated world in which the masses are reduced to eating different varieties of "soylent" -- a synthetic food that suggests both soybeans and lentils. The line from the movie that inspired the title of this paper comes is delivered when someone discovers that soylent green is actually made of cadavers from a government sponsored euthanasia program -- prompting the phrase "Soylent green, it's made of people!" The computer scientists are playing off this famous phrase with their title: "Soylent Grid: it's Made of People!" The idea being that people from all over the world need to jump through anti-spam hoops such as CAPTCHAs, and the power of these people can be harnessed through a grid structure to do some good in the world.
Article: "Soylent Grid: it's Made of People!" by Stephan Steinbach, Vincent Rabaud and Serge Belongie
Note: This story has been adapted from material provided by University of California - San Diego.

Fausto Intilla

www.oloscience.com

Quantum Computing Possibilites Enhanced With New Material

2007-10-09T11:16:00.000-07:00

Source:

http://www.sciencedaily.com/releases/2007/10/071008103647.htm

Science Daily — Scientists at Florida State University's National High Magnetic Field Laboratory and the university's Department of Chemistry and Biochemistry have introduced a new material that could be to computers of the future what silicon is to the computers of today.

The material -- a compound made from the elements potassium, niobium and oxygen, along with chromium ions -- could provide a technological breakthrough that leads to the development of new quantum computing technologies. Quantum computers would harness the power of atoms and molecules to perform memory and processing tasks on a scale far beyond those of current computers.
"The field of quantum information technology is in its infancy, and our work is another step forward in this fascinating field," said Saritha Nellutla, a postdoctoral associate at the magnet lab and lead author of the paper published in Physical Review Letters.
Semiconductor technology is close to reaching its performance limit. Over the years, processors have shrunk to their current size, with the components of a computer chip more than 1,000 times smaller than the thickness of a human hair. At those very small scales, quantum effects -- behaviors in matter that occur at the atomic and subatomic levels -- can start playing a role. By exploiting those behaviors, scientists hope to take computing to the next level.
In current computers, the basic unit of information is the "bit," which can have a value of 0 or 1. In so-called quantum computers, which currently exist only in theory, the basic unit is the "qubit" (short for quantum bit). A qubit can have not only a value of 0 or 1, but also all kinds of combinations of 0 and 1 -- including 0 and 1 at the same time -- meaning quantum computers could perform certain kinds of calculations much more effectively than current ones.
How scientists realize the promise of the theoretical qubit is not clear. Various designs and paths have been proposed, and one very promising idea is to use tiny magnetic fields, called "spins." Spins are associated with electrons and various atomic nuclei.
Magnet lab scientists used high magnetic fields and microwave radiation to "operate" on the spins in the new material they developed to get an indication of how long the spin could be controlled. Based on their experiments, the material could enable 500 operations in 10 microseconds before losing its ability to retain information, making it a good candidate for a qubit.
Putting this spin to work would usher in a technological revolution, because the spin state of an electron, in addition to its charge, could be used to carry, manipulate and store information.
"This material is very promising," said Naresh Dalal, a professor of chemistry and biochemistry at FSU and one of the paper's authors. "But additional synthetic and magnetic characterization work is needed before it could be made suitable for use in a device."
Dalal also serves as an adviser to FSU chemistry graduate student Mekhala Pati, who created the material.
Note: This story has been adapted from material provided by Florida State University.

Fausto Intilla

www.oloscience.com

Running Shipwreck Simulations Backwards Helps Identify Dangerous Waves

2007-10-04T23:30:00.000-07:00

Source:

http://www.sciencedaily.com/releases/2007/10/071001165915.htm

Science Daily — Big waves in fierce storms have long been the focus of ship designers in simulations testing new vessels.
But a new computer program and method of analysis by University of Michigan researchers makes it easy to see that a series of smaller waves—a situation much more likely to occur—could be just as dangerous.
"Like the Edmund Fitzgerald that sank in Michigan in 1975, many of the casualties that happen occur in circumstances that aren't completely understood, and therefore they are difficult to design for," said Armin Troesch, professor of naval architecture and marine engineering. "This analysis method and program gives ship designers a clearer picture of what they're up against."
Troesch and doctoral candidate Laura Alford will present a paper on their findings Oct. 2 at the International Symposium on Practical Design of Ships and Other Floating Structures, also known as PRADS 2007.
Today's ship design computer modeling programs are a lot like real life, in that they go from cause to effect. A scientist tells the computer what type of environmental conditions to simulate, asking, in essence, "What would waves like this do to this ship?" The computer answers with how the boat is likely to perform.
Alford and Troesch's method goes backwards, from effect to cause. To use their program, a scientist enters a particular ship response, perhaps the worst case scenario. The question this time is more like, "What are the possible wave configurations that could make this ship experience the worst case scenario?" The computer answers with a list of water conditions.
What struck the researchers when they performed their analysis was that quite often, the biggest ship response is not caused by the biggest waves. Wave height is only one contributing factor. Others are wave grouping, wave period (the amount of time between wave crests), and wave direction.
"In a lot of cases, you could have a rare response, but when we looked at just the wave heights that caused that response, we found they're not so rare," Alford said. "This is about operational conditions and what you can be safely sailing in. The safe wave height might be lower than we thought."
This new method is much faster than current simulations. Computational fluid dynamics modeling in use now works by subjecting the virtual ship to random waves. This method is extremely computationally intensive and a ship designer would have to go through months of data to pinpoint the worst case scenario.
Alford and Troesch's program and method of analysis takes about an hour. And it gives multiple possible wave configurations that could have statistically caused the end result.
There's an outcry in the shipping industry for advanced ship concepts, including designs with more than one hull, Troesch said. But because ships are so large and expensive to build, prototypes are uncommon. This new method is meant to be used in the early stages of design to rule out problematic architectures. And it is expected to help spur innovation.
A majority of international goods are still transported by ship, Troesch said.
The paper is called "A Methodology for Creating Design Ship Responses."
Note: This story has been adapted from material provided by University of Michigan.

Fausto Intilla
www.oloscience.com

Software 'Chipper' Speeds Debugging

2007-10-04T23:28:00.000-07:00

Source:

http://www.sciencedaily.com/releases/2007/10/071002135536.htm

Science Daily — Computer scientists at UC Davis have developed a technique to speed up program debugging by automatically "chipping" the software into smaller pieces so that bugs can be isolated more easily.
Computer programs consist of thousands, tens or even hundreds of thousands of lines of code. To isolate a bug in the code, programmers often break it into smaller pieces until they can pin down the error in a smaller stretch that is easier to manage. UC Davis graduate student Chad Sterling and Ron Olsson, professor of computer science, set out to automate that process.
"It's really tedious to go through thousands of lines of code," Olsson said.
The "Chipper" tools developed by Sterling and Olsson chip off pieces of software while preserving the program structure.
"The pieces have to work after they are cut down," Olsson said. "You can't just cut in mid-sentence."
In a recent paper in the journal "Software -- Practice and Experience," Olsson and Sterling describe ChipperJ, a version developed for the Java programming language. ChipperJ was able to reduce large programs to 20 to 35 percent of their former size in under an hour.
More information about automated program chipping is available on Olsson's Web site at http://www.cs.ucdavis.edu/~olsson/
Note: This story has been adapted from material provided by University of California, Davis.

Fausto Intilla
www.oloscience.com

'Dead Time' Limits Quantum Cryptography Speeds

2007-10-03T10:37:00.000-07:00

Source:

http://www.sciencedaily.com/releases/2007/09/070928104257.htm

Science Daily — Quantum cryptography is potentially the most secure method of sending encrypted information, but does it have a speed limit" According to a new paper* by researchers at the National Institute of Standards and Technology (NIST) and the Joint Quantum Institute** (JQI), technological and security issues will stall maximum transmission rates at levels comparable to that of a single broadband connection, such as a cable modem, unless researchers reduce "dead times" in the detectors that receive quantum-encrypted messages.
In quantum cryptography, a sender, usually designated Alice, transmits single photons, or particles of light, encoding 0s and 1s to a recipient, "Bob." The photons Bob receives and correctly measures make up the secret "key" that is used to decode a subsequent message. Because of the quantum rules, an eavesdropper, "Eve," cannot listen in on the key transmission without being detected, but she could monitor a more traditional communication (such as a phone call) that must take place between Alice and Bob to complete their communication.
Modern telecommunications hardware easily allows Alice to transmit photons at rates much faster than any Internet connection. But at least 90 percent (and more commonly 99.9 percent) of the photons do not make it to Bob's detectors, so that he receives only a small fraction of the photons sent by Alice. Alice can send more photons to Bob by cranking up the speed of her transmitter, but then, they'll run into problems with the detector's "dead time," the period during which the detector needs to recover after it detects a photon. Commercially available single-photon detectors need about 50-100 nanoseconds to recover before they can detect another photon, much slower than the 1 nanosecond between photons in a 1-Ghz transmission.
Not only does dead time limit the transmission rate of a message, but it also raises security issues for systems that use different detectors for 0s and 1s. In that important "phone call," Bob must report the time of each detection event. If he reports two detections occurring within the dead time of his detectors, then Eve can deduce that they could not have come from the same detector and correspond to opposite bit values.
Sure, Bob can choose not to report the second, closely spaced photon, but this further decreases the key production rate. And for the most secure type of encryption, known as a one-time pad, the key has to have as many bits of information as the message itself.
The speed limit would go up, says NIST physicist Joshua Bienfang, if researchers reduce the dead time in single-photon detectors, something that several groups are trying to do. According to Bienfang, higher speeds also would be useful for wireless cryptography between a ground station and a satellite in low-Earth orbit. Since the two only would be close enough to communicate for a small part of the day, it would be beneficial to send as much information as possible during a short time window.
* D.J. Rogers, J.C. Bienfang, A. Nakassis, H. Xu and C.W. Clark, Detector dead-time effects and paralyzability in high-speed quantum key distribution, New Journal of Physics (September 2007);EJ/abstract/-kwd=nj-2f2/1367-2630/9/9/319.
**The JQI is a research partnership that includes NIST and the University of Maryland.
Note: This story has been adapted from material provided by National Institute of Standards and Technology.

Fausto Intilla
www.oloscience.com

Technology Could Enable Computers To 'Read The Minds' Of Users

2007-10-03T10:23:00.000-07:00

Source:

http://www.sciencedaily.com/releases/2007/10/071001125649.htm

Science Daily — Tufts University researchers are developing techniques that could allow computers to respond to users' thoughts of frustration -- too much work -- or boredom--too little work. Applying non-invasive and easily portable imaging technology in new ways, they hope to gain real-time insight into the brain's more subtle emotional cues and help provide a more efficient way to get work done.
"New evaluation techniques that monitor user experiences while working with computers are increasingly necessary," said Robert Jacob, computer science professor and researcher. "One moment a user may be bored, and the next moment, the same user may be overwhelmed. Measuring mental workload, frustration and distraction is typically limited to qualitatively observing computer users or to administering surveys after completion of a task, potentially missing valuable insight into the users' changing experiences."
Sergio Fantini, biomedical engineering professor, in conjunction with Jacob's human-computer interaction (HCI) group, is studying functional near-infrared spectroscopy (fNIRS) technology that uses light to monitor brain blood flow as a proxy for workload stress a user may experience when performing an increasingly difficult task. A $445,000 grant from the National Science Foundation will allow the interdisciplinary team to incorporate real-time biomedical data with machine learning to produce a more in-tune computer user experience.
Lighting up the brain
"fNIRS is an emerging non-invasive, lightweight imaging tool which can measure blood oxygenation levels in the brain," said Fantini, also an associate dean for graduate education at Tufts' School of Engineering.
The fNIRS device, which looks like a futuristic headband, uses laser diodes to send near-infrared light through the forehead at a relatively shallow depth--only two to three centimeters--to interact with the brain's frontal lobe. Light usually passes through the body's tissues, except when it encounters oxygenated or deoxygenated hemoglobin in the blood. Light waves are absorbed by the active, blood-filled areas of the brain and any remaining light is diffusely reflected to the fNIRS detectors.
"fNIRS, like MRI, uses the idea that blood flow changes to compensate for the increased metabolic demands of the area of the brain that's being used," said Erin Solovey, a graduate researcher at the School of Engineering.
"We don't know how specific we can be about identifying users' different emotional states," said Fantini. "However, the particular area of the brain where the blood flow change occurs should provide indications of the brain metabolic changes and by extension workload, which could be a proxy for emotions like frustration."
In the initial experiments, Jacob and Fantini's groups determined how accurately fNIRS could register users' workload. While wearing the fNIRS device, test subjects viewed a multicolored cube consisting of eight smaller cubes with two, three or four different colors. As the cube rotated onscreen, subjects counted the number of colored squares in a series of 30 tasks. The fNIRS device and subsequent user surveys reflected greater difficulty as users kept track of increasing numbers of colors. The fNIRS data agreed with user surveys up to 83 percent of the time.
The Tufts group will present its initial results on using fNIRS to detect the user workload experience at the Association for Computing Machinery (ACM) symposium on user interface software and technology, to be held Oct. 7 through 10 in Newport, R.I.
"It seems that we can predict, with relatively high confidence, whether the subject was experiencing no workload, low workload, or high workload," said Leanne Hirshfield, a graduate researcher and lead author on the poster paper to be presented at the ACM symposium.
Note: This story has been adapted from material provided by Tufts University.

Fausto Intilla
www.oloscience.com

Any Digital Camera Can Take Multibillion-pixel Shots With New Device

2007-09-29T10:56:00.000-07:00

Source:

http://www.sciencedaily.com/releases/2007/09/070926111630.htm

Science Daily — Researchers at Carnegie Mellon University, in collaboration with scientists at NASA's Ames Research Center, have built a low-cost robotic device that enables any digital camera to produce breathtaking gigapixel (billions of pixels) panoramas, called GigaPans.

The technology gives people a new way to make and share images of their environment. It is being used by students to document their communities and by the Commonwealth of Pennsylvania to make Civil War sites accessible on the Web. To promote further sharing of this imagery, Carnegie Mellon has launched a public Web site, http://www.gigapan.org/, where people can upload and interactively explore panoramic images of any format.
In cooperation with Google, researchers also have created a GigaPan layer on Google Earth. Anyone using Google Earth can now fly into these GigaPan panoramas in the context of exploring the world.
Researchers have begun a public beta process with the GigaPan hardware, Web site, and software. The hardware technology enabling GigaPan images is a robotic camera mount, jointly designed and manufactured by Charmed Labs of Austin Texas. The tripod-like mount makes it possible for a digital camera to take hundreds of overlapping images of landscapes, buildings or rooms. Then, using software developed by Carnegie Mellon and Ames, these images can be arranged in a grid and digitally stitched together into a single image that could consist of tens of billions of pixels.
These huge image files can then be explored by zooming in on features of interest in a manner similar to Google Earth. "We have taken imagery and made it a new tool for exploration and for enhancing global understanding," said Illah Nourbakhsh, associate professor in the School of Computer Science's Robotics Institute. Nourbakhsh and Randy Sargent, senior systems scientist at Carnegie Mellon West in Moffett Field, Calif., led GigaPan's development. "An ordinary photo makes it possible to cross language barriers," Nourbakhsh explained. "But a GigaPan provides so much information that it leads to conversations between the person who took the panoramas and the people who are exploring it and discovering new details."
Last spring, the Pennsylvania Board of Tourism began to use GigaPan to enable people to virtually explore Civil War sites. The technology is also being used for Robot250, an arts-based robotics program in the Pittsburgh area. Robot250 will increase technical literacy by teaching students, artists and other members of the public how to build customized robots.
Nourbakhsh and his colleagues recently began to work with UNESCO's International Bureau of Education and its Associated Schools Network on a project that will link school children in different parts of the world in exploring issues of cultural identity through a classroom project. Middle school children from Pittsburgh to South Africa to Trinidad and Tobago will use the GigaPan camera to share images of their neighborhoods, lives and cultures. "This project will explore curriculum development from the local to the global level," said IBE Director Clementina Acedo.
"It is an extraordinary opportunity to link a school-community based educational practice with high-end technology in the service of children's innovative learning, personal development and world communication. Plans call for the experiences of these children from poorer and richer countries to be presented at the 48th session of the International Conference of Education scheduled to take place in Geneva in November 2008.
Besides being a tool for education, Nourbakhsh and Sargent see the GigaPan system as an important tool for ecologists, biologists and other scientists. They plan to foster this effort by making several dozen GigaPans available to leading scientists with support from the Fine Foundation of Pittsburgh.
Nourbakhsh hopes the non-commercial GigaPan site will help to develop a community of GigaPan producers and users. "We're not interested in becoming just another photo-sharing site," he said. "We want as many people as possible involved. GigaPan is not just about the vision of the person who makes the image. People who explore the image can make discoveries and gain insights in ways that may be just as important."
Sargent got the idea for GigaPan when he was a technical staff member at Ames Research Center, helping to develop software for combining images from NASA's Mars Exploration Rovers into panoramas. He became convinced that the same technology could open people's eyes to the diversity of their own planet. "It is increasingly important to give people a broad view of the world, particularly to help us understand different cultures and different environments," he said. "It's too easy to have blinders on and to only see and understand what is local."
The GigaPan camera system is part of a larger effort known as the Global Connection Project, led by Nourbakhsh and Sargent. Its purpose is to make people all over the world more aware of their neighbors.
Note: This story has been adapted from material provided by Carnegie Mellon University.

Fausto Intilla

www.oloscience.com

Superconducting Quantum Computing Cable Created

2007-09-27T02:35:00.000-07:00

Source:

http://www.sciencedaily.com/releases/2007/09/070926172232.htm

Science Daily — Physicists at the National Institute of Standards and Technology (NIST) have transferred information between two "artificial atoms" by way of electronic vibrations on a microfabricated aluminum cable, demonstrating a new component for potential ultra-powerful quantum computers of the future.

The setup resembles a miniature version of a cable-television transmission line, but with some powerful added features, including superconducting circuits with zero electrical resistance, and multi-tasking data bits that obey the unusual rules of quantum physics.
The resonant cable might someday be used in quantum computers, which would rely on quantum behavior to carry out certain functions, such as code-breaking and database searches, exponentially faster than today's most powerful computers.
Moreover, the superconducting components in the NIST demonstration offer the possibility of being easier to manufacture and scale up to a practical size than many competing candidates, such as individual atoms, for storing and transporting data in quantum computers.
Unlike traditional electronic devices, which store information in the form of digital bits that each possess a value of either 0 or 1, each superconducting circuit acts as a quantum bit, or qubit, which can hold values of 0 and 1 at the same time. Qubits in this "superposition" of both values may allow many more calculations to be performed simultaneously than is possible with traditional digital bits, offering the possibility of faster and more powerful computing devices. The resonant section of cable shuttling the information between the two superconducting circuits is known to engineers as a "quantum bus," and it could transport data between two or more qubits.
The NIST work is featured on the cover of the Sept. 27 issue of Nature. The scientists encoded information in one qubit, transferred this information as microwave energy to the resonant section of cable for a short storage time of 10 nanoseconds, and then successfully shuttled the information to a second qubit.
"We tested a new element for quantum information systems," says NIST physicist Ray Simmonds. "It's really significant because it means we can couple more qubits together and transfer information between them easily using one simple element."
The NIST work, together with another letter in the same issue of Nature by a Yale University group, is the first demonstration of a superconducting quantum bus. Whereas the NIST scientists used the bus to store and transfer information between independent qubits, the Yale group used it to enable an interaction of two qubits, creating a combined superposition state. These three actions, demonstrated collectively by the two groups, are essential for performing the basic functions needed in a superconductor-based quantum information processor of the future.
In addition to storing and transferring information, NIST's resonant cable also offers a means of "refreshing" superconducting qubits, which normally can maintain the same delicate quantum state for only half a microsecond. Disturbances such as electric or magnetic noise in the circuit can rapidly destroy a qubit's superposition state. With design improvements, the NIST technology might be used to repeatedly refresh the data and extend qubit lifetime more than 100-fold, sufficient to create a viable short-term quantum computer memory, Simmonds says. NIST's resonant cable might also be used to transfer quantum information between matter and light -- microwave energy is a low-frequency form of light -- and thus link quantum computers to ultra-secure quantum communications systems.
If they can be built, quantum computers -- harnessing the unusual rules of quantum mechanics, the principles governing nature's smallest particles -- might be used for applications such as fast and efficient code breaking, optimizing complex systems such as airline schedules, making counterfeit-proof money, and solving complex mathematical problems. Quantum information technology in general allows for custom-designed systems for fundamental tests of quantum physics and as-yet-unknown futuristic applications.
A superconducting qubit is about the width of a human hair. NIST researchers fabricate two qubits on a sapphire microchip, which sits in a shielded box about 8 cubic millimeters in size. The resonant section of cable is 7 millimeters long, similar to the coaxial wiring used in cable television but much thinner and flatter, zig-zagging around the 1.1 mm space between the two qubits. Like a guitar string, the resonant cable can be stimulated so that it hums or "resonates" at a particular tone or frequency in the microwave range. Quantum information is stored as energy in the form of microwave particles or photons.
The NIST research was supported in part by the Disruptive Technology Office.
*M.A. Sillanpää, J.I. Park, and R.W. Simmonds. 2007. Coherent quantum state storage and transfer between two phase qubits via a resonant cavity. Nature, Sept. 27.
Note: This story has been adapted from a news release issued by National Institute of Standards and Technology.

Fausto Intilla

www.oloscience.com

Two Giant Steps In Advancement Of Quantum Computing Achieved

2007-09-27T02:32:00.000-07:00

Source:

http://www.sciencedaily.com/releases/2007/09/070926172350.htm

Science Daily — Two major steps toward putting quantum computers into real practice -- sending a photon signal on demand from a qubit onto wires and transmitting the signal to a second, distant qubit -- have been brought about by a team of scientists at Yale.

The accomplishments are reported in sequential issues of Nature on September 20 and September 27, on which it is highlighted as the cover along with complementary work from a group at the National Institute of Standards and Technologies.
Over the past several years, the research team of Professors Robert Schoelkopf in applied physics and Steven Girvin in physics has explored the use of solid-state devices resembling microchips as the basic building blocks in the design of a quantum computer. Now, for the first time, they report that superconducting qubits, or artificial atoms, have been able to communicate information not only to their nearest neighbor, but also to a distant qubit on the chip.
This research now moves quantum computing from "having information" to "communicating information." In the past information had only been transferred directly from qubit to qubit in a superconducting system. Schoelkopf and Girvin's team has engineered a superconducting communication 'bus' to store and transfer information between distant quantum bits, or qubits, on a chip. This work, according to Schoelkopf, is the first step to making the fundamentals of quantum computing useful.
The first breakthrough reported is the ability to produce on demand -- and control -- single, discrete microwave photons as the carriers of encoded quantum information. While microwave energy is used in cell phones and ovens, their sources do not produce just one photon. This new system creates a certainty of producing individual photons.
"It is not very difficult to generate signals with one photon on average, but, it is quite difficult to generate exactly one photon each time. To encode quantum information on photons, you want there to be exactly one," according to postdoctoral associates Andrew Houck and David Schuster who are lead co-authors on the first paper.
"We are reporting the first such source for producing discrete microwave photons, and the first source to generate and guide photons entirely within an electrical circuit," said Schoelkopf.
In order to successfully perform these experiments, the researchers had to control electrical signals corresponding to one single photon. In comparison, a cell phone emits about 10^23 (100,000,000,000,000,000,000,000) photons per second. Further, the extremely low energy of microwave photons mandates the use of highly sensitive detectors and experiment temperatures just above absolute zero.
"In this work we demonstrate only the first half of quantum communication on a chip -- quantum information efficiently transferred from a stationary quantum bit to a photon or 'flying qubit,'" says Schoelkopf. "However, for on-chip quantum communication to become a reality, we need to be able to transfer information from the photon back to a qubit."
This is exactly what the researchers go on to report in the second breakthrough. Postdoctoral associate Johannes Majer and graduate student Jerry Chow, lead co-authors of the second paper, added a second qubit and used the photon to transfer a quantum state from one qubit to another. This was possible because the microwave photon could be guided on wires -- similarly to the way fiber optics can guide visible light -- and carried directly to the target qubit. "A novel feature of this experiment is that the photon used is only virtual," said Majer and Chow, "winking into existence for only the briefest instant before disappearing."
To allow the crucial communication between the many elements of a conventional computer, engineers wire them all together to form a data "bus," which is a key element of any computing scheme. Together the new Yale research constitutes the first demonstration of a "quantum bus" for a solid-state electronic system. This approach can in principle be extended to multiple qubits, and to connecting the parts of a future, more complex quantum computer.
However, Schoelkopf likened the current stage of development of quantum computing to conventional computing in the 1950's, when individual transistors were first being built. Standard computer microprocessors are now made up of a billion transistors, but first it took decades for physicists and engineers to develop integrated circuits with transistors that could be mass produced.
Schoelkopf and Girvin are members of the newly formed Yale Institute for Nanoscience and Quantum Engineering (YINQE), a broad interdisciplinary activity among faculty and students from across the university.
Other Yale authors involved in the research are J.M. Gambetta, J.A. Schreier, J. Koch, B.R. Johnson, L. Frunzio, A. Wallraff, A. Blais and Michel Devoret. Funding for the research was from the National Security Agency under the Army Research Office, the National Science Foundation and Yale University.
Citation: Nature 449, 328-331 (20 September 2007) doi:10.1038/nature06126 , Nature 450, 443-447 (27 September 2007) doi:10.1038/nature06184
Note: This story has been adapted from a news release issued by Yale University.

Fausto Intilla

www.oloscience.com

'Printers' That Can Make 3-D Solid Objects Soon To Enter Mainstream

2007-09-27T02:30:00.000-07:00

Source:

http://www.sciencedaily.com/releases/2007/09/070925081418.htm

Science Daily — It is a simple matter to print an E-book or other document directly from your computer, whether that document is on your hard drive, at a web site or in an email. But, imagine being able to 'print' solid objects, a piece of sports equipment, say, or a kitchen utensil, or even a prototype car design for wind tunnel tests. US researchers suggest such 3-D printer technology will soon enter the mainstream once a killer application emerges.
Such technology already exists and is maturing rapidly so that high-tech designers and others can share solid designs almost as quickly as sending a fax. The systems available are based on bath of liquid plastic which is solidified by laser light. The movements of the laser are controlled by a computer that reads a digitized 3D map of the solid object or design.
Writing in the Inderscience publication International Journal of Technology Marketing, US researchers discuss how this technology might eventually move into the mainstream allowing work environments to 3-D print equipment, whether that is plastic paperclips, teacups, or components that can be joined to make sophisticated devices, perhaps bolted together with printed nuts and bolts.
Physicist Phil Anderson of the School of Theoretical and Applied Science working with Cherie Ann Sherman of the Anisfield School of Business, both at Ramapo College of New Jersey, in Mahwah, New Jersey, explain how this technology, which is known formally as 'rapid prototyping' could revolutionize the way people buy goods.
It will allow them to buy or obtain a digital file representing a physical product electronically and then produce the object at a time and place convenient to them. The technology will be revolutionary in the same way that music downloads have shaken up the music industry. "This technology has the potential to generate a variety of new business models, which would enhance the average consumer's lifestyle," say the paper's authors.
The team discusses the current advanced applications of rapid prototyping which exist in the military where missing and damaged components can be produced at the site of action. Education too can make use of 3-D printing to allow students to make solid their experimental designs.
Also, product developers can share tangible prototypes by transferring the digitized design without the delay of shipping a solid object between sites, which may be separated by thousands of miles. The possibilities for consumer goods, individualized custom products, replacement components, and quick fixes for broken objects, are almost unlimited, the authors suggest.
From the business perspective, e-commerce sites will essentially become digital download sites with physical stores, retail employees, and shipping eliminated. It is only a matter of time before the 'killer application,' the 3-D equivalent of the mp3 music file, one might say, arrives to make owning a 3-D printer as necessary to the modern lifestyle as owning a microwave oven, a TV, or indeed a personal computer.
Note: This story has been adapted from a news release issued by Inderscience Publishers.

Fausto Intilla
www.oloscience.com

Computer Memory Designed In Nanoscale Can Retrieve Data 1,000 Times Faster

2007-09-19T04:57:00.000-07:00

Source:

http://www.sciencedaily.com/releases/2007/09/070917115319.htm

Science Daily — Scientists from the University of Pennsylvania have developed nanowires capable of storing computer data for 100,000 years and retrieving that data a thousand times faster than existing portable memory devices such as Flash memory and micro-drives, all using less power and space than current memory technologies.
Ritesh Agarwal, an assistant professor in the Department of Materials Science and Engineering, and colleagues developed a self-assembling nanowire of germanium antimony telluride, a phase-changing material that switches between amorphous and crystalline structures, the key to read/write computer memory. Fabrication of the nanoscale devices, roughly 100 atoms in diameter, was performed without conventional lithography, the blunt, top-down manufacturing process that employs strong chemicals and often produces unusable materials with space, size and efficiency limitations.
Instead, researchers used self-assembly, a process by which chemical reactants crystallize at lower temperatures mediated by nanoscale metal catalysts to spontaneously form nanowires that were 30-50 nanometers in diameter and 10 micrometers in length, and then they fabricated memory devices on silicon substrates.
"We measured the resulting nanowires for write-current amplitude, switching speed between amorphous and crystalline phases, long-term durability and data retention time," Agarwal said.
Tests showed extremely low power consumption for data encoding (0.7mW per bit). They also indicated the data writing, erasing and retrieval (50 nanoseconds) to be 1,000 times faster than conventional Flash memory and indicated the device would not lose data even after approximately 100,000 years of use, all with the potential to realize terabit-level nonvolatile memory device density.
"This new form of memory has the potential to revolutionize the way we share information, transfer data and even download entertainment as consumers," Agarwal said. "This represents a potential sea-change in the way we access and store data."
Phase-change memory in general features faster read/write, better durability and simpler construction compared with other memory technologies such as Flash. The challenge has been to reduce the size of phase change materials by conventional lithographic techniques without damaging their useful properties. Self-assembled phase-change nanowires, as created by Penn researchers, operate with less power and are easier to scale, providing a useful new strategy for ideal memory that provides efficient and durable control of memory several orders of magnitude greater than current technologies.
"The atomic scale of the nanodevices may represent the ultimate size limit in current-induced phase transition systems for non-volatile memory applications," Agarwal said.
Current solid-state technology for products like memory cards, digital cameras and personal data assistants traditionally utilize Flash memory, a non-volatile and durable computer memory that can be erased and reprogrammed electronically. Data on Flash drives provides most battery-powered devices with acceptable levels of durability and moderately fast data access. Yet the technology's limits are apparent. Digital cameras can't snap rapid-fire photos because it takes precious seconds to store the last photo to memory. If the memory device is fast, as in DRAM and SRAM used in computers, then it is volatile; if the plug on a desktop computer is pulled, all recent data entry is lost.
Therefore, a universal memory device is desired that can be scalable, fast, durable and nonvolatile, a difficult set of requirements which have now been demonstrated at Penn.
"Imagine being able to store hundreds of high-resolution movies in a small drive, downloading them and playing them without wasting time on data buffering, or imagine booting your laptop computer in a few seconds as you wouldn't need to transfer the operating system to active memory" Agarwal said.
The research was performed by Agarwal, Se-Ho Lee and Yeonwoong Jung of the Department of Materials Science and Engineering in the School of Engineering and Applied Science at Penn. The findings appear online in the journal Nature Nanotechnology and in the October print edition.
The research was supported by the Materials Research Science and Engineering Center at Penn, the University of Pennsylvania Research Foundation award and a grant from the National Science Foundation.
Note: This story has been adapted from a news release issued by University of Pennsylvania.

Fausto Intilla
www.oloscience.com

Getting There Faster With Virtual Reality

2007-09-11T22:59:00.000-07:00

Source:

http://www.sciencedaily.com/releases/2007/09/070909214527.htm

Science Daily — Is the navigation system too complex? Does it distract the driver’s attention from the traffic? To test electronic assistants, their developers have to build numerous prototypes – an expensive and time-consuming business. Tests in a virtual world make prototypes unnecessary.

The engineer stares intently at the display on the virtual dashboard. His task is to test the new driver assistance system from the user’s perspective. How seriously does it distract a driver to listen to a text message while negotiating a roundabout?
How does the driver apprehend a collision warning in the fog? Developers of electronic assistants have to build large numbers of prototypes and test countless functions. A great deal of time and money must therefore be invested before the product is ready to go on the market. Tomorrow’s engineers will have a much easier time: They can simply create virtual prototypes and simulate all the functions in a virtual world.
Car manufacturers and suppliers will be the chief beneficiaries of Personal Immersion® in future. Developed by the Fraunhofer Institute for Industrial Engineering IAO in Stuttgart, this virtual reality and stereoscopic interactive simulation system makes it possible to display tailored virtual environments for purposes such as the development of driver assistance systems.
“Our VR system not only simulates the instruments,” explains IAO project manager Manfred Dangelmaier. “Every level of this system is virtual. The user is seated in a virtual driving simulator, surrounded by a virtual world, facing a virtual dashboard with a virtual control system.” This allows the engineers to simulate every conceivable situation in order to test the man-machine interfaces. Whatever traffic situation is to be illustrated, and whatever demands the driver may make on the vehicle electronics, such as retrieving up-to-date traffic jam warnings – there are no limits to the imagination when testing these systems.
“Interactive simulation of this kind significantly cuts development time and costs,” says Dangelmaier. Virtual reality also facilitates communication within the interdisciplinary teams engaged in immersive design.
Up to now, a major problem in portraying virtual worlds was the projector resolution. “In technical terms, it is not easy to achieve a satisfactory portrayal of both the full-size surroundings and the close-up details at the same time in a virtual environment,” says Dangelmaier. But the researchers have solved the problem: Instead of the two projectors customary in VR systems, their systems operate with four projectors in a complex stereo projection setup. The scientists will be presenting potential applications at the International Motor Show (IAA) in Frankfurt on September 13 through 23.
Note: This story has been adapted from a news release issued by Fraunhofer-Gesellschaft.

Fausto Intilla

www.oloscience.com

Computerized Treatment Of Manuscripts

2007-09-07T00:25:00.000-07:00

Source:

http://www.sciencedaily.com/releases/2007/09/070906093357.htm

Science Daily — Researchers at the UAB Computer Vision Centre working on the automatic recognition of manuscript documents have designed a new system that is more efficient and reliable than currently existing ones.
The BSM (acronym for "Blurred Shape Model") has been designed to work with ancient, damaged or difficult to read manuscripts, handwritten scores and architectural drawings. It represents at the same time an effective human machine interface in automatically reproducing documents while they are being written or drawn.
Researchers based their work on the biological process of the human mind and its ability to see and interpret all types of images (recognition of shapes, structures, dimensions, etc.) to create description and classification models of handwritten symbols. However, this computerised system differs from others since it can detect variations, elastic deformations and uneven distortions that can appear when manually reproducing any type of symbol (letters, signs, drawings, etc.). Another advantage is the possibility to work in real time, only a few seconds after the document has been introduced into the computer.
The BSM differs from other existing systems which follow the same process when deciphering different types of symbols, since a standard process makes it more difficult to recognise the symbols after they have been introduced. In contrast, the methodology developed by the Computer Vision Centre can be adapted to each of the areas it is applied to.
To be able to analyse and recognise symbols, the system divides image regions into sub regions - with the help of a grid - and saves the information from each grid square, while registering even the smallest of differences (e.g. between p and b). Depending on the shape introduced, the system undergoes a process to distinguish the shape and also any possible deformations (the letter P for example would be registered as being rounder or having a shorter or longer stem, etc.). It then stores this information and classifies it automatically.
Researchers decided to test the efficiency of the system by experimenting with two application areas. They created a database of musical notes and a database of architectural symbols. The first was created from a collection of modern and ancient musical scores (from the 18th and 19th centuries) from the archives of the Barcelona Seminary, which included a total of 2,128 examples of three types of musical notes drawn by 24 different people. The second database included 2,762 examples of handwritten architectural symbols belonging to 14 different groups. Each group contained approximately 200 types of symbols drawn by 13 different people.
In order to compare the performance and reliability of the BSM, the same data was introduced into other similar systems. The BSM was capable of recognising musical notes with an exactness of over 98% and architectural symbols with an exactness of 90%.
Researchers at the Computer Vision Centre who developed the BSM were awarded the first prize in the third edition of the Iberian Conference on Pattern Recognition and Image Analysis (IbPRIA) which took place last June.
Note: This story has been adapted from a news release issued by Universitat Autonoma de Barcelona.

Fausto Intilla
www.oloscience.com