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08.08

Washington Technology Digest

Compiled By IEEE-USA Staff

The following is a roundup of news and notable developments in electrical engineering and computer or information technology emerging from the federal government during June and July 2008. Items are excerpted from news releases generated by research universities and government agencies. Highlighted topics include:

1. Tongue-Drive System Allows Disabled to Operate Wheelchairs and Computers
2. Advance Promises Low-Cost LED Lighting
3. Organic Light-Emitting Devices Promise Lighting Efficiency
4. Potential Demonstrated for Windows to Serve as Solar Energy Sources
5. With New Data Analytics, Argonne Set to Offer World’s Fastest Open Science Supercomputer
6. New Type of MRI Enables Study of Magnets for Computer Memory
7. Research Funding Targets New Software for Multithread Supercomputers
8. Nanoscale Lithography Advance Could Lead to Next Generation Computer Chips, Solar Cells and More
9. Penn State Researchers Explore More Cost-Effective Technique for Generating Hydrogen Fuel
10. ORNL Demonstrated Supersensitive Explosives Detector
11. Researchers Simulate Visual Cloaking Effects Using Silicon Photonic Crystals
12. “Nanosculpture” Could Enable New Types of Heat Pumps and Energy Converters
13. Use of Clickers Enhances Physics Education
14. Purdue Develops Virtual Environment as Research Tool
15. Nano-Sized electronic Circuit is Sensitive to “Invisible Light”
16. Nanoparticle Additives Improve Energy Efficiency of Cooling Systems

1. TONGUE-DRIVE SYSTEM ALLOWS DISABLED TO OPERATE WHEELCHAIRS AND COMPUTERS

A new assistive technology developed by engineers at the Georgia Institute of Technology with funding support by the National Science Foundation allows individuals with disabilities to operate a computer, control a powered wheelchair and interact with their environments simply by moving their tongues.

The system involves attaching a small magnet, the size of a grain of rice, to an individual’s tongue by implantation, piercing or tissue adhesive. Movement of the magnetic tracer attached to the tongue is detected by an array of magnetic field sensors mounted on a headset outside the mouth or on an orthodontic brace inside the mouth. This allows tongue motion to direct the movement of a cursor across a computer screen or a powered wheelchair around a room.

“We chose the tongue to operate the system because unlike hands and feet, which are controlled by the brain through the spinal cord, the tongue is directly connected to the brain by a cranial nerve that generally escapes damage in severe spinal cord injuries or neuromuscular diseases,” said Maysam Ghovanloo, an assistant professor in the Georgia Tech School of Electrical and Computer Engineering, who started working on this project about three years ago at North Carolina State University. “Tongue movements are also fast, accurate and do not require much thinking, concentration or effort.”

For more information, see: http://gtresearchnews.gatech.edu/newsrelease/tongue-drive.htm

2. ADVANCE PROMISES LOW-COST LED LIGHTING

DOE-funded researchers at Purdue University have overcome a major obstacle in reducing the cost of "solid state lighting," a technology that could cut electricity consumption by 10 percent if widely adopted. The Purdue team used a technique common in the electronics industry called reactive sputter deposition to to produce an efficient LED created directly on a silicon substrate with a metallic reflective layer. Using silicon will enable industry to "scale up" the process, by manufacturing multiple devices on large wafers of silicon. At the same time, silicon dissipates heat more efficiently than current substrates, reducing damage caused by heating, which is likely to improve reliability and increase the lifetime of LED lighting.

The technology, called light-emitting diodes, or LEDs, is about four times more efficient than conventional incandescent lights and more environmentally friendly than compact fluorescent bulbs. The LEDs also are expected to be far longer lasting than conventional lighting, lasting perhaps as long as 15 years before burning out.

For more information, see: http://news.uns.purdue.edu/x/2008b/080717SandsLighting.html

3. ORGANIC LIGHT-EMITTING DEVICES PROMISE LIGHTING EFFICIENCY

In the August issue of Nature Photonics, scientists at the University of Michigan and Princeton University describe a way to deliver significantly more bright light from a watt than incandescent bulbs by using white organic light-emitting devices (WOLEDs)

Incandescent light bulbs give off light as a by-product of heat, The light is appealing, but inefficient, putting out 15 lumens of light for every watt or electricity. The best fluorescent tube lights put out some 90 lumens of light per watt, but the light can be harsh, the fixtures are expensive, and the tubes lose their efficiency with age. And they rely on many environmentally unfriendly substances such as mercury.

The paper describes a tandem system of organic grids and micro lenses that guide the light out of the thin layers and into the air. The grids refract the trapped light, bouncing it into a layer of dome-shaped lenses that then pull the light out. This process — all of which is packed into a lighting sandwich roughly the thickness of a sheet of paper — was shown to emit approximately 70 lumens from a single watt of power.

If the costs of production can be reduced, WOLEDs show promise of providing a light that's much easier to manipulate, while being long lasting and able to provide in different shapes, from panels to bulbs and more.

For more information, see: www.ns.umich.edu/htdocs/releases/story.php?id=6648

4. POTENTIAL DEMONSTRATED FOR WINDOWS TO SERVE AS SOLAR ENERGY SOURCES

As reported in Science (11 July), MIT engineers funded by the Department of Energy and the National Science Foundation have reported success in using large glass panes as solar collectors, opening up the prospect that windows could be used to generate power, as well as provide a view and help illuminate rooms.

"Light is collected over a large area [like a window] and gathered, or concentrated, at the edges," explains Marc A. Baldo, leader of the work and the Esther and Harold E. Edgerton Career Development Associate Professor of Electrical Engineering. In addition, the focused light increases the electrical power obtained from each solar cell "by a factor of over 40," Baldo says.

Because the system is simple to manufacture, the team believes that it could be implemented within three years — even added onto existing solar-panel systems to increase their efficiency by 50 percent for minimal additional cost. That, in turn, would substantially reduce the cost of solar electricity.

For more information, see: www.eurekalert.org/pub_releases/2008-07/miot-mon070708.php

5. WITH NEW DATA ANALYTICS, ARGONNE SET TO OFFER WORLD’S FASTEST OPEN SCIENCE SUPERCOMPUTER

The IBM Blue Gene/P Intrepid at the Argonne Leadership Computing Facility (ALCF), located at the U.S. Department of Energy's (DOE) Argonne National Laboratory, will soon have the data analytics and visualization capability to complement its distinction as the fastest computer in the world for open science and the third fastest overall computer in the world.

For more information, see: www.eurekalert.org/pub_releases/2008-07/dnl-lda072208.php

6. NEW KIND OF MRI ENABLES STUDY OF MAGNETS FOR COMPUTER MEMORY

DOE-funded researchers at Ohio State University are investigating the insides of extremely tiny ferromagnets, developing a new type of MRI technique that may eventually enable the development of extremely small computers, and even give doctors a new tool for studying the plaques in blood vessels that play a role in diseases such as heart disease. As reported in Physical Review Letters, they were able to obtain an image resolution of 250 nanometers (billionths of a meter). With the technique in place, the OSU team is beginning to record the properties of many different kinds of tiny magnets — a critical first step toward developing them for computer memory.

For biomedical research, the technique could be used to study tissue samples taken from plaques that form in brain tissues and arteries in the body. Many diseases are associated with plaques, including Alzheimer's and atherosclerosis. Currently, researchers are trying to study the structure of plaques in detail to understand how they form and how they affect conventional MRI images.

For more information, see: http://researchnews.osu.edu/archive/nanomag.htm

7. RESEARCH FUNDING TARGETS NEW SOFTWARE FOR MULTITHREAD SUPERCOMPUTERS

The Department of Defense has awarded a $4 million grant to a multi-institutional group of researchers to seed the Center for Adaptive Supercomputing Software, a joint project between the Department of Energy's Pacific Northwest National Laboratory and Cray, Inc, in Seattle. The Center will develop new software that takes advantage of the multithread processors in the Cray XMT, which enable multiple, simultaneous processing capable of tackling large networks of seemingly random data.

"The system will allow much faster analysis of complex problems, like understanding and predicting how the power grid behaves — one of the most complex engineering systems ever built," said Moe Khaleel, director of Computational Sciences and Mathematics at PNNL, which is leading the project. Other possible applications include Internet security and understanding of complex biological networks.

For more information, see: www.eurekalert.org/pub_releases/2008-07/dnnl-mss071408.php

8. NANOSCALE LITHOGRAPHY ADVANCE COULD LEAD TO NEXT GENERATION COMPUTER CHIPS, SOLAR CELLS AND MORE

MIT researchers report achieving a significant advance in nanoscale lithographic technology, used in the manufacture of computer chips and other electronic devices, to make finer patterns of lines over larger areas than have been possible with other methods. Their new technique could pave the way for next-generation computer memory and integrated-circuit chips, as well as advanced solar cells and other devices.

The team has created lines about 25 nanometers (billionths of a meter) wide separated by 25 nm spaces. For comparison, the most advanced commercially available computer chips today have a minimum feature size of 65 nm. Intel recently announced that it will start manufacturing at the 32 nm minimum line-width scale in 2009, and the industry roadmap calls for 25 nm features in the 2013-2015 time frame.

The MIT technique could also be economically attractive because it works without the chemically amplified resists, immersion lithography techniques and expensive lithography tools that are widely considered essential to work at this scale with optical lithography.

For more information, see: www.eurekalert.org/pub_releases/2008-07/miot-mrf070808.php

9. PENN STATE RESEARCHERS EXPLORE MORE COST-EFFECTIVE
TECHNIQUE FOR GENERATING HYDROGEN FUEL

"Other researchers have developed ways to produce hydrogen with mind-boggling efficiency, but their approaches are very high cost," says Craig A. Grimes, professor of electrical engineering. "We are working toward something that is cost effective."

Currently, the steam reforming of natural gas produces most of our hydrogen. As a fuel source, this produces two problems. The process uses natural gas and so does not reduce reliance on fossil fuels; and, because one byproduct is carbon dioxide, the process contributes to the carbon dioxide in the atmosphere, the carbon footprint.

Grimes' process splits water into its two components, hydrogen and oxygen, and collects the products separately using commonly available titanium and copper. Splitting water for hydrogen production is an old and proven method, but in its conventional form, it requires previously generated electricity. Photolysis of water solar splitting of water has also been explored, but is not a commercial method yet.

Grimes and his team are producing hydrogen from solar energy, using two different groups of nanotubes in a photoelectrochemical diode. They report in the July issue of Nano Letters that using incident sunlight, "such photocorrosion-stable diodes generate a photocurrent of approximately 0.25 milliampere per centimeter square, at a photoconversion efficiency of 0.30 percent."

Although 0.30 percent efficiency is low, Grimes notes that this is just a first go and that the device can be readily optimized. "These devices are inexpensive and because they are photo-stable could last for years," says Grimes. "I believe that efficiencies of 5 to 10 percent are reasonable."

For more information, see: www.eurekalert.org/pub_releases/2008-07/ps-rgh071508.php

10. ORNL DEMONSTRATES SUPERSENSITIVE EXPLOSIVES DETECTOR

Using a laser and a device that converts reflected light into sound, researchers at the Department of Energy's Oak Ridge National Laboratory can detect explosives at distances exceeding 20 yards.

ORNL's technique, detailed in Applied Physics Letters 92, involves illuminating the target sample with an eye-safe pulsed light source and allowing the scattered light to be detected by a quartz crystal tuning fork.

The method is a variation of photoacoustic spectroscopy but overcomes a number of problems associated with this technique originally demonstrated by Alexander Graham Bell in the late 1880s. Most notably, ORNL researchers are able to probe and identify materials in open air instead of having to introduce a pressurized chamber, which renders photoacoustic spectroscopy virtually useless for security and military applications.

For more information, see: www.eurekalert.org/pub_releases/2008-06/drnl-ods062508.php

11. RESEARCHERS SIMULATE VISUAL CLOAKING EFFECTS USING SILICON PHOTONIC CRYSTALS

In computer simulations, the researchers have demonstrated an approximate cloaking effect created by concentric rings of silicon photonic crystals. The mathematical proof brings scientists a step closer to a practical solution for optical cloaking.

"This is much more than a theoretical exercise," said Harley Johnson, a Cannon Faculty Scholar and professor of mechanical science and engineering at Illinois. "An optical cloaking device is almost within reach."

The researchers' optical cloaking technique is not perfect, however. "The wave fronts are slightly perturbed as they pass around the container," said Johnson. "Because the wave fronts don't match exactly, we refer to the technique as 'approximate' cloaking."

For more information, see: www.eurekalert.org/pub_releases/2008-06/uoia-spc062508.php

12. “NANOSCULPTURE” COULD ENABLE NEW TYPES OF HEAT PUMPS AND ENERGY CONVERTERS

Researchers at Rensselaer Polytechnic Institute have discovered a new technique for growing single-crystal nanorods and controlling their shape using biomolecules. The research, published in the journal Advanced Materials, could enable the development of smaller, more powerful heat pumps and devices that harvest electricity from heat.

For more information, see: http://news.rpi.edu/update.do?artcenterkey=2471

13. USE OF CLICKERS ENHANCES PHYSICS EDUCATION

According to an NSF-funded study, hand-held electronic devices (“clickers”) used in the classroom are helping college students learn physics, according to a series of research studies. Ohio State University students who used the devices to answer multiple-choice questions during physics lectures earned final examination scores that were around 10 percent higher — the equivalent of a full-letter grade — than students who didn't.

The clickers also appear to level the playing field between male and female students. In clicker classes, male and female students performed equally well. In the traditional, non-clicker classes, male students outperformed female students.

In clicker classes, multiple choice questions appear on a large computer screen at the front of the lecture hall. Students hold the wireless devices, which resemble small calculators. They cast their votes for the correct answer based on their understanding of the part of the lecture that was just given. A bar graph shows the percentage of students voting for each answer.

Physics educators have expanded the use of clickers at Ohio State by developing sequences of questions to determine if students really understand the underlying concepts of a lecture. The technique involves offering a series of questions — typically three — each with different wording and structure, but all designed to test the same concept.

For more information, see: http://researchnews.osu.edu/archive/clickers.htm

14. PURDUE DEVELOPS VIRTUAL ENVIRONMENT AS RESEARCH TOOL

Purdue University is operating a virtual environment that enables scientists and engineers to interpret raw data collected with powerful instruments called dynamic atomic force microscopes.

The online tools, believed to be the first of their kind for the instruments, represent a research trend, with tools for other applications also being developed, said Arvind Raman, a Purdue professor of mechanical engineering.

"We will see more and more of this sort of thing for many other types of instruments that are being used around the world," he said. "This allows researchers to spend more time doing research and less time and money developing simulations."

The online tools are provided through the nanoHub, operated by the Network for Computational Nanotechnology at Purdue, led by Mark Lundstrom, Purdue's Scifres Distinguished Professor of Electrical and Computer Engineering.

More than 300 researchers from around the world have used the "virtual environment for dynamic atomic force microscopy," or VEDA, since it went online about a year ago.

For more information, see: http://news.uns.purdue.edu/x/2008b/080716RamanAtomic.html

15. NANO-SIZED ELECTRONIC CIRCUIT IS SENSITIVE TO “INVISIBLE LIGHT”

A newly developed nano-sized electronic device developed for use on satellite-based far-infrared telescopes is an important step toward helping astronomers see invisible light dating from the creation of the universe. This invisible light makes up 98 percent of the light emitted since the "big bang," and may provide insights into the earliest stages of star and galaxy formation almost 14 billion years ago.

A 100 times smaller than the thickness of a human hair, the new device was developed by researchers at Rutgers University, NASA’s Jet Propulsion Laboratory and the State University of New York at Buffalo.

For more information, see: http://news.rutgers.edu/medrel/news-releases/2008/07/nano-sized-electroni-20080710

16. NANOPARTICLE ADDITIVES IMPROVE ENERGY EFFICIENCY OF COOLING SYSTEMS

Adding just the right dash of nanoparticles to standard mixes of lubricants and refrigerants could yield the equivalent of an energy-saving chill pill for factories, hospitals, ships, and others with large cooling systems, suggest the latest results from National Institute of Standards and Technology (NIST) research that is pursuing promising formulations.

NIST experiments with varying concentrations of nanoparticle additives indicate a major opportunity to improve the energy efficiency of large industrial, commercial, and institutional cooling systems known as chillers. These systems account for about 13 percent of the power consumed by the nation’s buildings, and about 9 percent of the overall demand for electric power, according to the Department of Energy.

NIST researcher Mark Kedzierski has found that dispersing “sufficient” amounts of copper oxide particles (30 nanometers in diameter) in a common polyester lubricant and combining it with an equally pedestrian refrigerant (R134a) improves heat transfer by between 50 percent and 275 percent. “We were astounded,” he says.

For more information, see: www.nist.gov/public_affairs/techbeat/tb2008_0722.htm#cool

Comments may be submitted to todaysengineer@ieee.org.