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July 26, 2006, 5:17 PM CT

how well wind turbines operate?

how well wind turbines operate?
In West Texas, New Mexico, and other places around the world, wind turbines are used to generate electricity. But how can engineers determine their efficiency and health?

Sandia's Wind Energy Technology Department has developed a device, the Accurate Time Linked data Acquisition System (ATLAS II), which answers that question and can provide all of the information necessary to understand how well a machine is performing.

Housed in an environmentally protected aluminum box, ATLAS II is capable of sampling a large number of signals at once to characterize the inflow, the operational state, and the structural response of a wind turbine.

The ATLAS II has several key attributes that make it especially attractive for wind turbine deployment. It is small, highly reliable, can operate continuously, uses off-the-shelf components, and has lightning protection on all channels.

"The system provides us with sufficient data to help us understand how our turbine blade designs perform in real-world conditions, allowing us to improve on the original design and our design codes," says Jose Zayas, the project lead, who has been working on ATLAS II since its inception in 1999.

Last year the ATLAS II team completed a project with GE Energy and the National Renewable Energy Laboratory (NREL) to monitor the performance of a GE wind turbine in a Great Plains site about 30 miles south of Lamar, Colo., and will soon start monitoring a new work-for-others (WFO) project with Texas Tech University.........

Posted by: John      Permalink         Source


July 26, 2006, 5:02 PM CT

Global Coral Reef Assessment

Global Coral Reef Assessment
A first-of-its-kind survey of how well the world's coral reefs are being protected was made possible by a unique collection of NASA views from space.

A team of international scientists using NASA satellite images compiled an updated inventory of all "marine protected areas" containing coral reefs and compared it with the most detailed and comprehensive satellite inventory of coral reefs. The global satellite mapping effort is called the Millennium Coral Reef Mapping Project and was funded by NASA. The study was reported on recently in the journal Science.

The assessment observed that less than two percent of coral reefs are within areas designated to limit human activities that can harm the reefs and the sea life living in and around them. Countries around the world have created these protected ocean and coastal zones where human activities such as shipping, fishing, recreation and scientific research are restricted to varying degrees.

"The contribution of NASA images to this project was crucial," says study lead author Camilo Mora, a marine biologist at Dalhousie University, Canada. "The satellite images allowed us to pinpoint where coral reefs are actually located within coastal marine ecosystems."

The Millennium Project collection of global satellite images of coral reefs was first released in 2003; maps derived from these images were released in 2004. The images are now publicly available from NASA's Goddard Space Flight Center, Greenbelt, Md. Landsat 7 was designed by NASA and launched in 1999. The Landsat Program is a series of Earth-observing satellite missions jointly managed by NASA and the Department of the Interior's U.S. Geological Survey.........

Posted by: Edwin      Permalink         Source


July 26, 2006, 7:00 AM CT

S-VIEW SV510 portable video key

S-VIEW SV510 portable video key
Piracy is rampant in the software and entertainment industries, and you can sometime find bootleg versions of the latest movies and games before they are even officially released. Cinea has introduced a new solution to this age-old problem with the S-VIEW SV510, a USB key that enables the playback of protected digital content.

Should the USB key be lost or stolen, this device can be disconnected remotely. Movie studios should look into this offering from Cinea in order to reduce the risk of piracy. The S-VIEW SV510 comes with a six to twelve digit access code for security purposes and can be deregistered should the situation call for it.........

Posted by: John      Permalink         Source


July 25, 2006, 6:54 PM CT

Red Spots of Jupiter

Red Spots of Jupiter
A high-resolution image just released by the Gemini Observatory shows two giant red spots brushing past one another in Jupiter's southern hemisphere.

The image was obtained in near infrared light using adaptive optics which removed most of the distortions caused by turbulence in Earth's atmosphere. The result is a view from the ground that rivals images from space.

"It was tricky getting this picture," said Gemini astronomer Chad Trujillo who helped lead the effort to capture the image. "Since we used adaptive optics we needed a star-like object nearby to guide on, so we had to find a time when Jupiter's moon Io would appear close enough to Jupiter and the red spots would be optimally placed on Jupiter's disk. Fortunately it all worked out on the evening of July 13th and we were able to capture this relatively rare set of circumstances," said Trujillo.

Professor Steve Miller of University College London is a keen Jupiter-watcher and said The latest images from Gemini are truly amazing in the detail that they show of these two major storm systems on Jupiter. It is now clear that they are lined up more or less "on top" of each other, with the smaller storm further south, closer to the South Pole.

Both red spots are massive storm systems. The larger one, known for a long time as the Great Red Spot, lies about 8 kilometres (5 miles) above the neighbouring cloud tops and is the largest hurricane known in the solar system. The smaller storm (officially called Oval BA, but informally known as Red Spot Junior) is another hurricane-like system. Since it appears nearly as bright as the Great Red Spot in near-infrared images, Red Spot Junior may be at a similar height in the Jovian atmosphere as the Great Red Spot.........

Posted by: Edwin      Permalink         Source


July 24, 2006, 6:43 AM CT

Fuel cells, a clean source of energy

Fuel cells, a clean source of energy
"Fuel cells are a genuine 'clean' technology," says one of the study's investigators, Professor Chris Hendry of the Cass Business School, London. "But re-investment in nuclear technology is likely to squeeze out the investment necessary to make fuel cells competitive with existing energy sources and with other non-nuclear alternative energy options".

The study, co-written by Prof. Hendry, Dr. Paul Harborne, James Brown and Prof. Dinos Arcoumanis, gives a strong clue to one of the major obstacles to development by referring to fuel cell technology as a disruptive innovation. A disruptive innovation, if proved to be successful, eventually overturns the existing product on the market. Recent examples include the digital camera and the compact disc. Disruptive innovations are radically different from the existing dominant technology and to begin with they are often not as good. The result is two hundred percent. First the proponents of existing technology are likely to fear and so resist the new development. Second, because profits are unlikely to be immediate, funding can be problematic.

The automotive industry and stationary power provide examples of fuel cells as a disruptive innovation. However, while their potential is being pursued in the UK, Gera number of, North America and Japan, interviews with seventy companies in these countries show the UK fuel cell industry is lagging behind.........

Posted by: John      Permalink         Source


July 22, 2006, 10:14 PM CT

Accelerating The Speed Of Light

Accelerating The Speed Of Light
Physicist Costas Soukoulis and his research group at the U.S. Department of Energy's Ames Laboratory on the Iowa State University campus are having the time of their lives making light travel backwards at negative speeds that appear faster than the speed of light. That, folks, is a mind-boggling 186,000 miles per second - the speed at which electromagnetic waves can move in a vacuum. And making light seem to move faster than that and in reverse is what Soukoulis, who is also an ISU Distinguished Professor of Liberal Arts and Sciences, said is "like rewriting electromagnetism." He predicted, "Snell's law on the refraction of light is going to be different; many other laws will be different".

However, neither Soukoulis nor any other scientist involved in efforts to manipulate the direction and speed of light can do so with naturally occurring materials. The endeavor requires exotic, artificially created materials. Known as metamaterials, these substances can be manipulated to respond to electromagnetic waves in ways that natural materials cannot. Natural materials refract light, or electromagnetic radiation, to the right of the incident beam at different angles and speeds. However, metamaterials, also called left-handed materials, make it possible to refract light at a negative angle, so it emerges on the left side of the incident beam. This backward-bending characteristic of metamaterials allows enhanced resolution in optical lenses, which could potentially lead to the development of a flat superlens with the power to see inside a human cell and diagnose disease in a baby still in the womb.........

Posted by: John      Permalink         Source


July 21, 2006, 7:12 AM CT

Nuclear explosion on a dead star

Nuclear explosion on a dead star

A team of astronomers from the UK and Gera number of have observed that a nuclear explosion on the surface of a star 5,000 light years from Earth resulted in a blast wave moving at over 1,700 km per second (one thousand miles per second or almost four million miles per hour!). The discovery, published in the 20 recent issue of Nature, was made by bringing together a number of of the world's radio telescopes into arrays capable of seeing the aftermath of the explosion in incredible detail.

During the night of 12 February this year Japanese astronomers reported that a star called RS Ophiuchi had suddenly brightened and become clearly visible in the night sky. Eventhough this was the latest in a series of such outbursts that have been spotted over the last hundred years or so, it was the first since 1985 and therefore an opportunity to bring to bear new, more powerful, telescopes in an effort to understand the causes and consequences of these eruptions.

Dr Tim OBrien of The University of Manchesters Jodrell Bank Observatory requested urgent observations with the VLBA (the Very Long Baseline Array of radio telescopes extending from Hawaii to the Caribbean). Our first observations, made only two weeks after the explosion was reported, showed an expanding blast wave already comparable in size to Saturns orbit around the Sun. However, we needed to use the worlds most powerful radio telescopes because, from a distance of 5,000 light years, its apparent size on the sky was only 5 millionths of a degree the size of a football seen from 2,700 km (1,700 miles) away.........

Posted by: Edwin      Permalink         Source


July 20, 2006, 9:57 PM CT

Nano-Etched Cavity Makes LEDs 7 Times Brighter

Nano-Etched Cavity Makes LEDs 7 Times Brighter Etched nanostructured rings around an LED can make it more than seven times brighter
Scientists at the National Institute of Standards and Technology (NIST) have made semiconductor light-emitting diodes (LEDs) more than seven times brighter by etching nanoscale grooves in a surrounding cavity to guide scattered light in one direction. The novel nanostructure, which may have applications in areas such as in biomedical imaging where LED brightness is crucial, is described in the July 17 issue of Applied Physics Letters.*.

Semiconductor LEDs are used increasingly in displays and a number of other applications, in part because they can efficiently produce light across a broad spectrum, from near-infrared to the ultraviolet. However, they typically emit only about two percent of the light in the desired direction: perpendicular to the diode surface. Far more light skims uselessly below the surface of the LED, because of the extreme mismatch in refraction between air and the semiconductor. The NIST nanostructured cavity boosts useful LED emission to about 41 percent and may be cheaper and more effective for some applications than conventional post-processing LED shaping and packaging methods that attempt to redirect light.

The NIST team fabricated their own infrared LEDs consisting of gallium arsenide packed with "quantum dots" of assorted sizes made of indium gallium arsenide. Quantum dots are nanoscale semiconductor particles that efficiently emit light at a color determined by the exact size of the particle. The LEDs were backed with an alumina mirror to reflect the light emitted backwards. The periphery of each LED was turned into a cavity etched with circular grooves, in which the light reflects and interferes with itself in an optimal geometry.........

Posted by: John      Permalink         Source


July 20, 2006, 7:48 PM CT

Samsung SGH-P20

 Samsung SGH-P20
The Samsung SGH-P200 is the world's first Unlicensed Mobile Access (UMA) phone. It can switch freely between GSM, GPRS, EDGE and wireless LAN networks (WiFi).

The phone sports a 1.3 megapixel camera as well as the following features: camcorder 80MB internal memory multimedia messaging system (MMS) MP3 player (MP3/ACC/ACC+ formats) video player (MPEG4/H.263 formats).........

Posted by: John      Permalink         Source


July 20, 2006, 6:07 PM CT

new light on superfluidity

new light on superfluidity mage courtesy / Martin Zwierlein
For the first time, MIT researchers have directly observed the transition of a gas to a superfluid, a form of matter closely correlation to the superconductors that allow electrical currents to travel without resistance.

Observations of superfluids may help solve lingering questions about high-temperature superconductivity, which has widespread applications for magnets, sensors and energy-efficient transport of electricity.

The superfluid gas created at MIT can also serve as an easily controlled model system to study properties of neutron stars or the quark-gluon plasma that existed in the early universe.

The work, published in the July 6 issue of Nature and in the July 18 issue of Physical Review Letters, was led by Nobel laureate Wolfgang Ketterle, the John D. MacArthur Professor of Physics and a principal investigator in MIT's Research Laboratory of Electronics.

The team observed the transition to superfluidity of a gas of so-called fermionic atoms. Fermionic atoms are atoms with an odd number of neutrons, protons and electrons. They can become superfluid only if they form pairs. These pairs then have an even number of basic constituents and can form a kind of Bose-Einstein condensate, a type of matter where all pairs act as a giant matter wave, "march in lockstep" and flow without friction.........

Posted by: John      Permalink         Source


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