May 23, 2006, 11:54 PM CT

Ultra Wideband Antenna

By taking advantage of a phenomenon that earlier designers had struggled to avoid, engineers at the Georgia Tech Research Institute (GTRI) have developed a new approach to phased-array antenna design that could allow a single ultra-wideband device to do the job of five conventional antennas.

The "Fragmented Aperture Antenna," a computer-designed planar system, has already demonstrated a 33-to-1 bandwidth - well beyond the 10-to-1 ratio achieved by conventional designs. The scientists believe they can extend that range to at least 100-to-1 for use in radar and communication applications.

"Phased array antennas take up space, and if you must have a different antenna for every function - communications, radar and other tasks - the space mandatory can be considerable," noted Paul Friederich, a principal research engineer in GTRI's Signature Technology Lab (STL). "On any military platform, space is at a premium. Our antenna can replace five conventional antennas, which would reduce the weight and volume mandatory for antennas."

The GTRI ultra-wideband antenna would also have applications in most Department of Defense agencies. Current ships must carry dozens of antennas - a problem for all ships, particularly submarines. Aircraft have limited surface area for antennas, with weight always a concern. Ground vehicles and even individual soldiers could benefit from reducing the number of antennas they must carry, Friederich noted.........

Posted by: Kevin      Permalink         Source

May 18, 2006, 11:31 PM CT

Phones Have Changed, But Teenaged Girls Have Not

Cellphones come in a number of shapes, colors and sizes now, but the teenaged girls who use them may not be very different than the young women who were learning how to use telephones more than 40 years ago.

A University of Alberta study reported in the recent issue of Journal of Youth Studies revealed that a group of teen girls aged 14 to 17, while attracted to the cool and hip images of cellular phone advertisements, expressed that a series of advertisements they were shown published in issues of Seventeen magazine from 1960 most reflected their experiences as users. These ads for Bell telephones showed young ladies the uses of a telephone, including helping friends with homework and talking about boys. A number of of the teens interviewed identified with these ads and the importance of friendship and responsibility that they showed, said researcher Rachel Campbell, author of the study and a PhD student in sociology at the University of Alberta in Edmonton, Canada.

In contrast, the freedom-filled world presented in a number of of today's cellular phone advertisements was not a reality in the eyes of these young women. They viewed their opportunities to 'go out' as limited, especially when compared to their male friends.

Campbell's study also found that most of the girls she talked with were given cellphones by their parents to keep them safe - a safety that the girls believed was a real concern. The young women recognized their parents' worry and emphasized wanting to be good, responsible daughters. Despite this, some of the girls admitted to occasionally wasting their parents' minutes, "fibbing" about where they were, or refusing to answer the cellphone's ring. Yet, Campbell said, "these actions never deviated far from what was expected by their parents. They still carried the cellphone and called home. They just wanted to create a space for themselves. With the cellphone a number of even said they 'felt safer'".........

Posted by: Kevin      Permalink         Source

May 18, 2006, 11:27 PM CT

Clocking Events At The Nanoscale

As researchers and engineers build devices at smaller and smaller scales, grasping the dynamics of how materials behave when they are subjected to electrical signals, sound and other manipulations has proven to be beyond the reach of standard scientific techniques.

But now a team of University of Wisconsin-Madison scientists has found a way to time such effects at the nanometer scale, in essence clocking the movements of atoms as they are manipulated using electric fields.

The accomplishment, published in the most recent edition (May 12, 2006) of the journal Physical Review Letters, is important because it gives researchers a way to probe another dimension of a material's structure at the scale of nanometers. Adding the dimension of time to their view of the nanoworld promises to enhance the ability to develop materials for improved memory applications in microelectronics of all kinds, among other things.

"Now we have a tool to look inside a device and see how it works at the spatial scale of nanometers and the time scale of nanoseconds," says Alexei Grigoriev, a UW-Madison postdoctoral fellow and the lead author of the Physical Review Letters paper.

With the advent of nanotechnology, the ability to make devices and products on a scale measured in atoms has mushroomed. Already, products with elements fabricated at the nanoscale are on the market, and researchers continue to hone the technology, which has potential applications in areas ranging from digital electronics to toothpaste.........

Posted by: Kevin      Permalink         Source

May 14, 2006, 3:34 PM CT

Low-cost Microfluidics Can Be A Sticky Problem

A deceptively simple approach to bonding thermoplastic microchannel plates together with solvent could be used for low-cost, high-volume production of disposable "lab-on-a-chip" devices, as per scientists from the National Institute of Standards and Technology (NIST) and George Mason University (GMU).

Microfluidics is considered a highly promising technology for performing rapid and inexpensive chemical and biochemical analyses. The defining feature of microfluidics is the use of tiny channels less than a fraction of a millimeter wide to move samples and reagents through the device. For high-volume production, the channels likely will be molded or embossed in high-quality thermoplastic and then sealed with a cover plate. Bonding the two pieces together securely without blocking or altering the tiny channels is a key manufacturing issue.

One approach is to weld the two plates together by clamping them and heating the plastic to the point where the polymer chains begin to diffuse together. This requires just the right combination of time, pressure and temperature--which unfortunately has to be fine-tuned for each new lot of plastic. The other method is to weld the pieces with a solvent-type glue, like a model plane, but as model-builders will appreciate, the problem is keeping the glue where you want it and away from where you don't want it.........

Posted by: Kevin      Permalink         Source

May 14, 2006, 9:02 AM CT

Sapphire Illuminated PC Keyboard

This Sapphire Illuminated PC Keyboard is a great solution for reducing your typos! The illuminated keyboard produces a soft, soothing sapphire-blue glow that reduces eyestrain and increases typing accuracy in low light. So, if you get finicky due to the distracting glare from overhead lighting then now you can go on typing flawlessly!! The super-slim keyboard sells for a price of $59.95 at Discovery store.

Cool Factor: Illuminating.........

Posted by: Kevin      Permalink         Source

May 14, 2006, 1:17 AM CT

Connectable Multimedia To The TV

Eventhough it is simple to mount a computer near the television set to be able to reproduce films or to listen to music, everybody does not have the time or the desire to do it. In that case, Mvix the Player Multimedia can be a good option.

This will allow you to reproduce video, audio and to see photographs, besides its ability to transmit the audio by means of an emitter FM, by which we could listen to it in our radio. It has outlets for Super Video and composite video, a remote port USB and remote control.

Its price is of 249 dollars, eventhough strangely it does not include hard disk, which we will have to add.........

Posted by: Gina      Permalink         Source

May 12, 2006, 0:17 AM CT

Tools To Analyze Musical Expression

Music expresses and elicits emotion. But how, exactly?

Philosophers have been fascinated by the question since Pythagoras. At the USC Viterbi School of Engineering, Elaine Chew, assistant professor of industrial and systems engineering, now teaches a graduate course on using computational and other engineering tools to look for answers.

Chew, who continues a career as a distinguished concert pianist in addition to her engineering research, has written an account of the issues in creating the course in an article that will be presented at an engineering conference later this year.

Meanwhile the students in "Computational Modeling of Expressive Performance" presented their results May 3, a collection of 10 projects now up on the class website as what Chew calls a "non-peer reviewed publication" at http://www-scf.usc.edu/~ise575/b/projects.

The projects from the class, offered for only the fourth time this Spring, range widely. Arpi Mardirossian found a trove of silent movie scores specially written to evoke specific emotions, and analyzed their characteristics.

For "Analysis of Dynamic Shaping in Unaccompanied Bach," student Eric Cheng created intricate graphs comparing, note-by-note, performances of a Bach unaccompanied violin sonata by three master violinists: Jascha Heifetz, Yehudi Menuhin, and Nathan Milstein, with respect to their dynamic shaping, i.e. the nature and amount of sound intensity variation.........

Posted by: Gina      Permalink         Source

May 12, 2006, 0:08 AM CT

Pollution, Greenhouse Gases And Climate Clash In South Asia

A new analysis by researchers at Scripps Institution of Oceanography at the University of California, San Diego, has produced surprising results showing how air pollution, global warming-producing greenhouse gases and natural fluctuations in the climate may have a range of significant consequences on the world's most populous region.

As per a research findings reported in the May 15 issue of the American Meteorological Society's Journal of Climate, Chul Eddy Chung and V. Ramanathan of Scripps Oceanography describe their analysis of sea-surface temperatures and a range of other data from the Indian Ocean region. In the analysis, they found that cooler-than-normal temperatures in the northern part of the ocean have weakened the natural climate circulation and monsoon conditions in the region, resulting in reduced rainfall over India and increased rainfall over the Sahel area south of the Sahara in Africa.

As the tropical Indian Ocean heats up due to greenhouse gases, the authors say, the northern Indian Ocean, which is adjacent to highly populated regions, is not warming as quickly as the rest of the ocean, resulting in increased drought conditions that could hold repercussions for more than 2 billion people in South Asia. These conditions impact a range of industries and resources, from agriculture to freshwater availability.........

Posted by: Tyler      Permalink         Source

May 12, 2006, 0:04 AM CT

First Synthetic Nanoscale Fractal Molecule

From snowflakes to the leaves on a tree, objects in nature are made of irregular molecules called fractals. Researchers now have created and captured an image of the largest man-made fractal molecule at the nanoscale.

The molecule, developed by scientists at the University of Akron, Ohio University and Clemson University, eventually could lead to new types of photoelectric cells, molecular batteries and energy storage, as per the scientists, whose study was published online today by the journal Science.

A University of Akron research team led by Vice President for Research George Newkome used molecular self-assembly techniques to synthesize the molecule in the laboratory. The molecule, bound with ions of iron and ruthenium, forms a hexagonal gasket.

Ohio University physicists Saw-Wai Hla and Violeta Iancu, who specialize in imaging objects at the nanoscale, confirmed the creation of the man-made fractal. To capture the image, the physicists sprayed the molecules onto a piece of gold, chilled them to minus 449 degrees Fahrenheit to keep them stable, and then viewed them with a scanning tunneling microscope.

Though invisible to the naked eye - the molecules are about one million times smaller than the colorful hexagons shown in the Science image - the objects are 12 nanometers wide. "That's big for a nanoscale molecule. It's huge," said Hla, an associate professor of physics and astronomy.........

Posted by: Kevin      Permalink         Source

May 11, 2006, 11:39 PM CT

Coffee, Black, Decaf And A Little Llama On The Side

Three llamas and two camels have provided a way to tell whether your waiter swapped regular coffee for decaf in your after-dinner cup. Using the heat-resistant antibodies these camels and llamas make, scientists at Washington University School of Medicine in St. Louis are developing a quick test for caffeine that works even with hot beverages.

The scientists plan to adapt their technology to a simple test ("dipstick") that can be used to check for caffeine in a variety of drinks. Their research will appear in the June 1 issue of the American Chemical Society's journal Analytical Chemistry.

Caffeine can cause restlessness, irritability, dehydration or heart arrythmias, and those who are highly sensitive to caffeine can feel its stimulant effects for as long as 20 hours. In addition, some medicines adversely interact with caffeine.

"We believe our test would be the first consumer test for caffeine and would be beneficial for anyone wishing to avoid caffeine for health or personal reasons," says senior author Jack H. Ladenson, Ph.D., the Oree M. Carroll and Lillian B. Ladenson Professor of Clinical Chemistry and director of the Division of Laboratory Medicine.

Interestingly, the key to the caffeine test comes from llamas and camels -- pack animals that have transported caffeinated commodities such as coffee, tea and cocoa for centuries. These camelids happen to be among the few creatures whose immune systems can produce antibodies that aren't destroyed at the high temperatures common to brewed beverages.........

Posted by: Kevin      Permalink         Source

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