Archive for February, 2011

February 23, 2011

>Toward Computers That Fit on a Pen Tip: New Technologies Usher in the Millimeter-Scale Computing Era

>

 

A prototype implantable eye pressure monitor for glaucoma patients is believed to contain the first complete millimeter-scale computing system.And a compact radio that needs no tuning to find the right frequency could be a key enabler to organizing millimeter-scale systems into wireless sensor networks. These networks could one day track pollution, monitor structural integrity, perform surveillance, or make virtually any object smart and trackable.Both developments at the University of Michigan are significant milestones in the march toward millimeter-scale computing, believed to be the next electronics frontier.Researchers are presenting papers on each at the International Solid-State Circuits Conference (ISSCC) in San Francisco. The work is being led by three faculty members in the U-M Department of Electrical Engineering and Computer Science: professors Dennis Sylvester and David Blaauw, and assistant professor David Wentzloff.

Bell’s Law and the promise of pervasive computing

Nearly invisible millimeter-scale systems could enable ubiquitous computing, and the researchers say that’s the future of the industry. They point to Bell’s Law, a corollary to Moore’s Law. (Moore’s says that the number of transistors on an integrated circuit doubles every two years, roughly doubling processing power.) Bell’s Law says there’s a new class of smaller, cheaper computers about every decade. With each new class, the volume shrinks by two orders of magnitude and the number of systems per person increases. The law has held from 1960s’ mainframes through the ’80s’ personal computers, the ’90s’ notebooks and the new millennium’s smart phones.”When you get smaller than hand-held devices, you turn to these monitoring devices,” Blaauw said. “The next big challenge is to achieve millimeter-scale systems, which have a host of new applications for monitoring our bodies, our environment and our buildings. Because they’re so small, you could manufacture hundreds of thousands on one wafer. There could be 10s to 100s of them per person and it’s this per capita increase that fuels the semiconductor industry’s growth.”

The first complete millimeter-scale system

Blaauw and Sylvester’s new system is targeted toward medical applications. The work they present at ISSCC focuses on a pressure monitor designed to be implanted in the eye to conveniently and continuously track the progress of glaucoma, a potentially blinding disease. (The device is expected to be commercially available several years from now.) In a package that’s just over 1 cubic millimeter, the system fits an ultra low-power microprocessor, a pressure sensor, memory, a thin-film battery, a solar cell and a wireless radio with an antenna that can transmit data to an external reader device that would be held near the eye.”This is the first true millimeter-scale complete computing system,” Sylvester said.”Our work is unique in the sense that we’re thinking about complete systems in which all the components are low-power and fit on the chip. We can collect data, store it and transmit it. The applications for systems of this size are endless.”The processor in the eye pressure monitor is the third generation of the researchers’ Phoenix chip, which uses a unique power gating architecture and an extreme sleep mode to achieve ultra-low power consumption. The newest system wakes every 15 minutes to take measurements and consumes an average of 5.3 nanowatts. To keep the battery charged, it requires exposure to 10 hours of indoor light each day or 1.5 hours of sunlight. It can store up to a week’s worth of information.While this system is miniscule and complete, its radio doesn’t equip it to talk to other devices like it. That’s an important feature for any system targeted toward wireless sensor networks.

A unique compact radio to enable wireless sensor networks

Wentzloff and doctoral student Kuo-Ken Huang have taken a step toward enabling such node-to-node communication. They’ve developed a consolidated radio with an on-chip antenna that doesn’t need the bulky external crystal that engineers rely on today when two isolated devices need to talk to each other. The crystal reference keeps time and selects a radio frequency band. Integrating the antenna and eliminating this crystal significantly shrinks the radio system. Wentzloff’s is less than 1 cubic millimeter in size.He and Huang’s key innovation is to engineer the new antenna to keep time on its own and serve as its own reference. By integrating the antenna through an advanced CMOS process, they can precisely control its shape and size and therefore how it oscillates in response to electrical signals.”Antennas have a natural resonant frequency for electrical signals that is defined by their geometry, much like a pure audio tone on a tuning fork,” Wentzloff said. “By designing a circuit to monitor the signal on the antenna and measure how close it is to the antenna’s natural resonance, we can lock the transmitted signal to the antenna’s resonant frequency.””This is the first integrated antenna that also serves as its own reference. The radio on our chip doesn’t need external tuning. Once you deploy a network of these, they’ll automatically align at the same frequency.”The researchers are now working on lowering the radio’s power consumption so that it’s compatible with millimeter-scale batteries.

Greg Chen, a doctoral student in the Department of Electrical Engineering and Computer Science, presents “A Cubic-Millimeter Energy-Autonomous Wireless Intraocular Pressure Monitor.” The researchers are collaborating with Ken Wise, the William Gould Dow Distinguished University Professor of Electrical Engineering and Computer Science on the packaging of the sensor, and with Paul Lichter, chair of the Department of Ophthalmology and Visual Sciences at the U-M Medical School, for the implantation studies. Huang presents “A 60GHz Antenna-Referenced Frequency-Locked Loop in 0.13μm CMOS for Wireless Sensor Networks.” This research is funded by the National Science Foundation. The university is pursuing patent protection for the intellectual property, and is seeking commercialization partners to help bring the technology to market.

Courtesy : ScienceDaily

 

Advertisements
February 17, 2011

>Running on a Faster Track: Researchers Develop Scheduling Tool to Save Time on Public Transport

>

 

What matters for commuters is not just if the train will be on time, but how long the journey will take. It’s an important factor in public transportation and can make the difference in helping commuters choose mass transit over more polluting and costly transport like cars or airplanes.Dr. Tal Raviv and his graduate student Mor Kaspi of Tel Aviv University’s Department of Industrial Engineering in the Iby and Aladar Fleischman Faculty of Engineering have developed a tool that makes passenger train journeys shorter, especially when transfers are involved — a computer-based system to shave precious travel minutes off a passenger’s journey.

Dr. Raviv’s solution, the “Service Oriented Timetable,” relies on computers and complicated algorithms to do the scheduling. “Our solution is useful for any metropolitan region where passengers are transferring from one train to another, and where train service providers need to ensure that the highest number of travellers can make it from Point A to Point B as quickly as possible,” says Dr. Raviv.

 

Saves time and resources

In the recent economic downturn, more people are seeking to scale back their monthly transportation costs. Public transportation is a win-win — good for both the bank account and the environment. But when travel routes are complicated by transfers, it becomes a hard job to manage who can wait — and who can’t — between trains.

Another factor is consumer preference. Ideally, each passenger would like a direct train to his destination, with no stops en route. But passengers with different itineraries must compete for the system’s resources. Adding a stop at a certain station will improve service for passengers for whom the station is the final destination, but will cause a delay for passengers who are only passing through it. The question is how to devise a schedule which is fair for everyone. What are the decisions that will improve the overall condition of passengers in the train system?

It’s not about adding more resources to the system, but more intelligently managing what’s already there, Dr. Raviv explains.

 

More time on the train, less time on the platform

In their train timetabling system, Dr. Raviv and Kaspi study the timetables to find places in the train scheduling system that can be optimized so passengers make it to their final destination faster.

Traditionally, train planners looked for solutions based on the frequency of trains passing through certain stops. Dr. Raviv and Kaspi, however, are developing a high-tech solution for scheduling trains that considers the total travel time of passengers, including their waiting time at transfer stations.

“Let’s say you commute to Manhattan from New Jersey every day. We can find a way to synchronize trains to minimize the average travel time of passengers,” says Dr. Raviv. “That will make people working in New York a lot happier.”

The project has already been simulated on the Israel Railway, reducing the average travel time per commuter from 60 to 48 minutes. The tool can be most useful in countries and cities, he notes, where train schedules are robust and very complicated.

The researchers won a competition of the Railway Application Section of the International Institute for Operation Research and Management Science (INFORMS) last November for their computer program that optimizes a refuelling schedule for freight trains. Dr. Raviv also works on optimizing other forms of public transport, including the bike-sharing programs found in over 400 cities around the world today.

Courtesy ScienceDaily

 

February 7, 2011

>Engineers Grow Nanolasers on Silicon, Pave Way for on-Chip Photonics

>

Engineers at the University of California, Berkeley, have found a way to grow They describe their work in a paper to be published Feb. 6 in an advanced online issue of the journal Nature Photonics.
“Our results impact a broad spectrum of scientific fields, including materials science, transistor technology, laser science, optoelectronics and optical physics,” said the study’s principal investigator, Connie Chang-Hasnain, UC Berkeley professor of electrical engineering and computer sciences.
The increasing performance demands of electronics have sent researchers in search of better ways to harness the inherent ability of light particles to carry far more data than electrical signals can. Optical interconnects are seen as a solution to overcoming the communications bottleneck within and between computer chips.
Because silicon, the material that forms the foundation of modern electronics, is extremely deficient at generating light, engineers have turned to another class of materials known as III-V (pronounced “three-five”) semiconductors to create light-based components such as light-emitting diodes (LEDs) and lasers.
But the researchers pointed out that marrying III-V with silicon to create a single optoelectronic chip has been problematic. For one, the atomic structures of the two materials are mismatched.
“Growing III-V semiconductor films on silicon is like forcing two incongruent puzzle pieces together,” said study lead author Roger Chen, a UC Berkeley graduate student in electrical engineering and computer sciences. “It can be done, but the material gets damaged in the process.”
Moreover, the manufacturing industry is set up for the production of silicon-based materials, so for practical reasons, the goal has been to integrate the fabrication of III-V devices into the existing infrastructure, the researchers said.
“Today’s massive silicon electronics infrastructure is extremely difficult to change for both economic and technological reasons, so compatibility with silicon fabrication is critical,” said Chang-Hasnain. “One problem is that growth of III-V semiconductors has traditionally involved high temperatures — 700 degrees Celsius or more — that would destroy the electronics. Meanwhile, other integration approaches have not been scalable.”
The UC Berkeley researchers overcame this limitation by finding a way to grow nanopillars made of indium gallium arsenide, a III-V material, onto a silicon surface at the relatively cool temperature of 400 degrees Celsius.
“Working at nanoscale levels has enabled us to grow high quality III-V materials at low temperatures such that silicon electronics can retain their functionality,” said Chen.
The researchers used metal-organic chemical vapor deposition to grow the nanopillars on the silicon. “This technique is potentially mass manufacturable, since such a system is already used commercially to make thin film solar cells and light emitting diodes,” said Chang-Hasnain.
Once the nanopillar was made, the researchers showed that it could generate near infrared laser light — a wavelength of about 950 nanometers — at room temperature. The hexagonal geometry dictated by the crystal structure of the nanopillars creates a new, efficient, light-trapping optical cavity. Light circulates up and down the structure in a helical fashion and amplifies via this optical feedback mechanism.
The unique approach of growing nanolasers directly onto silicon could lead to highly efficient silicon photonics, the researchers said. They noted that the miniscule dimensions of the nanopillars — smaller than one wavelength on each side, in some cases — make it possible to pack them into small spaces with the added benefit of consuming very little energy
“Ultimately, this technique may provide a powerful and new avenue for engineering on-chip nanophotonic devices such as lasers, photodetectors, modulators and solar cells,” said Chen.
“This is the first bottom-up integration of III-V nanolasers onto silicon chips using a growth process compatible with the CMOS (complementary metal oxide semiconductor) technology now used to make integrated circuits,” said Chang-Hasnain. “This research has the potential to catalyze an optoelectronics revolution in computing, communications, displays and optical signal processing. In the future, we expect to improve the characteristics of these lasers and ultimately control them electronically for a powerful marriage between photonic and electronic devices.”
The Defense Advanced Research Projects Agency and a Department of Defense National Security Science and Engineering Faculty Fellowship helped support this research.nanolasers directly onto a silicon surface, an achievement that could lead to a new class of faster, more efficient microprocessors, as well as to powerful biochemical sensors that use optoelectronic chips.
Thanks to ScienceDaily
February 7, 2011

>Math May Help Calculate Way to Find New Drugs for HIV and Other Diseases

>

Using mathematical concepts, Princeton researchers have developed a method of discovering new drugs for a range of diseases by calculating which physical properties of biological molecules may predict their effectiveness as medicines.
The technique already has identified several potential new drugs that were shown to be effective for fighting strains of HIV by researchers at Johns Hopkins University.
“The power of this is that it’s a general method,” said Princeton chemical and biological engineering professor Christodoulos Floudas, who led the research team. “It has proven successful in finding potential peptides to fight HIV, but it should also be effective in searching for drugs for other diseases.”
Floudas, the Stephen C. Macaleer ’63 Professor in Engineering and Applied Science, and Princeton engineering doctoral student Meghan Bellows-Peterson collaborated on the study with researchers at the Johns Hopkins University School of Medicine. Their findings were reported in the Nov. 17, 2010, issue of Biophysical Journal.
The researchers’ technique combines concepts from optimization theory, a field of mathematics that focuses on calculating the best option among a number of choices, with those of computational biology, which combines mathematics, statistics and computer science for biology research.
In the case of HIV, the challenge for the Princeton team was to find peptides — the small chains of biologically active amino acids that are the basic building blocks of proteins — that could stop the virus from infecting human cells.
“The Princeton researchers have a very sophisticated way of selecting peptides that will fit a particular binding site on an HIV virus,” said collaborator Robert Siliciano, a professor of medicine at Johns Hopkins and a 1974 Princeton graduate, who specializes in the treatment of HIV. “It narrows the possibilities, and may reduce the amount of time and resources it takes to find new drugs.”
Fuzeon (enfuvirtide), is a peptidic drug commonly given to HIV patients for whom first-line HIV medications have not proven fully effective. Fuzeon costs nearly $20,000 per year, and patients must take it regularly due to its short period of effectiveness in the body. The researchers hoped to find an alternative to Fuzeon by discovering new peptides that would be cheaper to produce and allow patients to take fewer and smaller doses.
Fuzeon is thought to inhibit HIV by attaching to the virus and disabling a structure used to penetrate the protective membrane of human cells.
“The actual mechanism for entering cells is still uncertain, but there is a lot of evidence that points to this certain structure on the virus,” Bellows-Peterson said. “We used the available data on the proteins that form the structure to help us predict what kind of drug might be effective against the virus.”
The researchers reasoned that a shorter peptide — Fuzeon is 36 amino acids long– would be cheaper to produce and would last longer in the body, since shorter molecules are less susceptible to breakdown. Such formulations also might allow for drugs that could be taken as a pill instead of an injection.
The researchers’ biological sleuthing focused on the physical relationship between peptides and the HIV protein structure that Fuzeon targets. The team developed a formula based on statistical thermodynamics to predict whether a given peptide, based on its sequence of amino acids, was likely to bind with the protein that HIV uses for penetrating cells.
This tendency to bind stems from the peptide’s free energy state, a physical property related to its shape, which would change if it attached to the HIV protein. The researchers looked for peptides that would shift to a lower energy state after binding to the HIV protein, because these would be more likely to bind to the protein and thus be capable of blocking the virus from entering a cell.
Out of millions of possible peptides, the Princeton researchers used their formula to narrow their search to five promising drug candidates, each 12 amino acids long, one-third the length of Fuzeon. Their collaborators at Johns Hopkins then tested whether the peptides were truly effective at preventing HIV from entering human cells.
The Johns Hopkins scientists found that four of the five designed peptides inhibited HIV and that one of the peptides was particularly potent, even against strains of HIV that are resistant to treatment with Fuzeon. They also found that peptides designed by the Princeton researchers were nontoxic to cells.
“One could never test all the possible peptides to see if they are effective against HIV,” Floudas said. “But this model was able to sort through millions of possibilities and identify just a few that show promise.”
Now that they have identified possible candidates, the researchers plan to experiment with modifying the shape of the peptides to see if they can be made even more effective against the virus. They also hope to expand the use of the model to other diseases, particularly cancers.
“It’s an approach to finding peptide-based drugs that target certain proteins, whether those of a virus or those of a cancerous cell,” Floudas said.
In addition to Siliciano, collaborators from Johns Hopkins included Lin Shen, a former doctoral student; Philip Cole, a professor of pharmacology; and Martin Taylor, an M.D./Ph.D. candidate who graduated from Princeton in 2005. Hoki Fung, a former Princeton doctoral student who is currently serving as a postdoctoral fellow at École polytechnique fédérale de Lausanne in Switzerland, also participated in the research.
The research was supported by the National Science Foundation.
Thanks to ScienceDaily
February 7, 2011

>Nokia E7 for Select Markets

>

Nokia has stated in a  press release that the Nokia E7 has started shipping and will be hitting select markets this week amd the availability will be broadened in the coming weeks.
Nokia is marketing the E7 mainly as a business phone. They are stating that with it’s tilting 4″ Clear Black Display, full hardware QWERTY keyboard and a fast access to a wide variety of apps directly on the homescreen, the Nokia E7 is the key to having a successful day in or out of the office.
February 6, 2011

>Women Subject to Objectifying Gazes Show Decreased Math Ability

>

Women who are looked at as sexual objects not only react as sexual objects, they also exhibit less proficiency with math, according to a new study published in the March 2011 issue of the journal Psychology of Women Quarterly.
The study examined the effect of the objectifying gaze (the visual inspection of one’s body by another person) on undergraduates’ math performance. Motivation to interact with the objectifying person in the future was also measured as well as body image outcomes, including body surveillance, body shame, and body dissatisfaction.
One hundred and fifty undergraduates (67 women and 83 men) from a large U.S. Midwestern university participated in the study.
Researchers found that the objectifying gaze lowered women’s math performance, but not men’s. The objectifying gaze also increased women’s, but not men’s, motivation to have further interactions with their partner. Finally, the research found that an objectifying gaze did not influence body surveillance, body shame, or body dissatisfaction for women or men.
“The objectifying gaze is particularly problematic for women,” write authors Sarah J. Gervais, Theresa K. Vescio, and Jill Allen. “And it may lead to a vicious cycle in which women are first objectified and, as a result, underperform, confirming the notion that women’s looks are more important than what they can do.”
Courtesy Science Daily .
February 6, 2011

>Sumatra PDF, the open-source Adobe Reader replacement, improves performance, printing

>

Sumatra (http://downloadsquad.switched.com/tag/Sumatra/ )— the lightweight, open source alternative to Adobe Reader — has just updated to version 1.3 and lead developer Krzysztof Kowalczyk has delivered some welcome improvements. Sumatra now uses libjpeg-turbo for faster rendering of some PDFs and its printing support has been improved. Documents can also be zoomed and rotated using your keyboard via the + and * keys, respectively.
February 6, 2011

>Future Surgeons May Use Robotic Nurse, ‘Gesture Recognition’

>

Surgeons of the future might use a system that recognizes hand gestures as commands to control a robotic scrub nurse or tell a computer to display medical images of the patient during an operation.
Both the hand-gesture recognition and robotic nurse innovations might help to reduce the length of surgeries and the potential for infection, said Juan Pablo Wachs, an assistant professor of industrial engineering at Purdue University.
The “vision-based hand gesture recognition” technology could have other applications, including the coordination of emergency response activities during disasters.
“It’s a concept Tom Cruise demonstrated vividly in the film ‘Minority Report,'” Wachs said.
Surgeons routinely need to review medical images and records during surgery, but stepping away from the operating table and touching a keyboard and mouse can delay the surgery and increase the risk of spreading infection-causing bacteria.
The new approach is a system that uses a camera and specialized algorithms to recognize hand gestures as commands to instruct a computer or robot.
At the same time, a robotic scrub nurse represents a potential new tool that might improve operating-room efficiency, Wachs said.
Findings from the research will be detailed in a paper appearing in the February issue of Communications of the ACM, the flagship publication of the Association for Computing Machinery. The paper was written by researchers at Purdue, the Naval Postgraduate School in Monterey, Calif., and Ben-Gurion University of the Negev, Israel.
Research into hand-gesture recognition began several years ago in work led by the Washington Hospital Center and Ben-Gurion University, where Wachs was a research fellow and doctoral student, respectively.
He is now working to extend the system’s capabilities in research with Purdue’s School of Veterinary Medicine and the Department of Speech, Language, and Hearing Sciences.
“One challenge will be to develop the proper shapes of hand poses and the proper hand trajectory movements to reflect and express certain medical functions,” Wachs said. “You want to use intuitive and natural gestures for the surgeon, to express medical image navigation activities, but you also need to consider cultural and physical differences between surgeons. They may have different preferences regarding what gestures they may want to use.”
Other challenges include providing computers with the ability to understand the context in which gestures are made and to discriminate between intended gestures versus unintended gestures.
“Say the surgeon starts talking to another person in the operating room and makes conversational gestures,” Wachs said. “You don’t want the robot handing the surgeon a hemostat.”
A scrub nurse assists the surgeon and hands the proper surgical instruments to the doctor when needed.
“While it will be very difficult using a robot to achieve the same level of performance as an experienced nurse who has been working with the same surgeon for years, often scrub nurses have had very limited experience with a particular surgeon, maximizing the chances for misunderstandings, delays and sometimes mistakes in the operating room,” Wachs said. “In that case, a robotic scrub nurse could be better.”
The Purdue researcher has developed a prototype robotic scrub nurse, in work with faculty in the university’s School of Veterinary Medicine.
Researchers at other institutions developing robotic scrub nurses have focused on voice recognition. However, little work has been done in the area of gesture recognition, Wachs said.
“Another big difference between our focus and the others is that we are also working on prediction, to anticipate what images the surgeon will need to see next and what instruments will be needed,” he said.
Wachs is developing advanced algorithms that isolate the hands and apply “anthropometry,” or predicting the position of the hands based on knowledge of where the surgeon’s head is. The tracking is achieved through a camera mounted over the screen used for visualization of images.
“Another contribution is that by tracking a surgical instrument inside the patient’s body, we can predict the most likely area that the surgeon may want to inspect using the electronic image medical record, and therefore saving browsing time between the images,” Wachs said. “This is done using a different sensor mounted over the surgical lights.”
The hand-gesture recognition system uses a new type of camera developed by Microsoft, called Kinect, which senses three-dimensional space. The camera is found in new consumer electronics games that can track a person’s hands without the use of a wand.
“You just step into the operating room, and automatically your body is mapped in 3-D,” he said.
Accuracy and gesture-recognition speed depend on advanced software algorithms.
“Even if you have the best camera, you have to know how to program the camera, how to use the images,” Wachs said. “Otherwise, the system will work very slowly.”
The research paper defines a set of requirements, including recommendations that the system should:
  1. Use a small vocabulary of simple, easily recognizable gestures.
  2. Not require the user to wear special virtual reality gloves or certain types of clothing.
  3. Be as low-cost as possible.
  4. Be responsive and able to keep up with the speed of a surgeon’s hand gestures.
  5. Let the user know whether it understands the hand gestures by providing feedback, perhaps just a simple “OK.”
  6. Use gestures that are easy for surgeons to learn, remember and carry out with little physical exertion.
  7. Be highly accurate in recognizing hand gestures.
  8. Use intuitive gestures, such as two fingers held apart to mimic a pair of scissors.
  9. Be able to disregard unintended gestures by the surgeon, perhaps made in conversation with colleagues in the operating room.
  10. Be able to quickly configure itself to work properly in different operating rooms, under various lighting conditions and other criteria.

“Eventually we also want to integrate voice recognition, but the biggest challenges are in gesture recognition,” Wachs said. “Much is already known about voice recognition.”
The work is funded by the U.S. Agency for Healthcare Research and Quality.
Thanks to Science Daily
February 6, 2011

>Nokia Bubbles – cool way to unlock your phone

>

Nokia Bubbles is a new app from Nokia BetaLabs which lets you unlock your phone in a totally different way. When your phone is locked , you press the menu button and you see bubbles floating on the screen that let you do various things with it like responding to missed calls or viewing new messages .
Following is the video of the idea prototype.
February 4, 2011

>Google Pushes Web Apps with Chrome 9 Release

>

The latest version of Google’s browser, Chrome 9, just hit the Web today and it comes with a couple of new features, like hardware-accelerated 3D graphics and Google Instant search directly from the address bar. Beyond that, however, the update comes with something else – a lesson on the evolution of the Internet and an introduction to “Web Apps” for the Internet layperson.