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June 28, 2006, 0:32 AM CT

Double vortex at Venus South Pole

Double vortex at Venus South Pole Infrared views of south polar double-vortex
ESA's Venus Express data undoubtedly confirm for the first time the presence of a huge 'double-eye' atmospheric vortex at the planet's south pole. This striking result comes from analysis of the data gathered by the spacecraft during the first orbit around the planet.

On 11 April this year, Venus Express was captured into a first elongated orbit around Venus, which lasted 9 days, and ranged between 350 000 and 400 kilometres from Venus' surface. This orbit represented for the Venus Express researchers a unique opportunity to observe the planet from large distances. This made it possible to obtain first clues about the Venusian atmospheric dynamics on a global scale, before the spacecraft got closer and started observing the planet in greater detail.

During this first orbit - called the 'capture orbit' - some of the Venus Express instruments were used to perform the first observations at different distances from Venus, for a few hours per time on six different slots between 12 and 19 April 2006.

Amazing infrared, visible and ultraviolet images of the Venusian globe already reveal several atmospheric features of great interest. The most striking of these is a huge, double-eye atmospheric vortex over the south pole, not dissimilar from the equivalent structure present at the north pole - the only one previously studied in some detail.........

Posted by: Edwin      Permalink         Source


June 28, 2006, 0:12 AM CT

Kidney Stone Prevention In Astronauts

Kidney Stone Prevention In Astronauts
As the space shuttle Discovery prepares to launch on July 1, scientists at the University of Minnesota have identified a way for astronauts to reduce their risk of developing kidney stones while in space.

Astronauts lose calcium in their bones and strength in their muscles while in space because of the zero-gravity environment. This calcium can end up in their kidneys, putting them at risk for developing kidney stones.

At least 14 American crew members have developed kidney stones in the last 5 years, and as missions become longer, the number is likely to grow. While astronauts have exercised in space to attempt to combat bone loss, the lack of gravity makes it difficult to achieve enough resistance to maintain their pre-flight fitness levels.

"This becomes a real health concern, as the time astronauts spend in space and living in the space station is extended," said Manoj Monga, M.D., professor of urologic surgery and lead investigator. The study would be reported in the July 2006 print issue of the Journal of Urology and is available online now.

Kidney stones are mineral deposits in the kidneys that can travel through the urinary tract, causing intense pain. One of the most common types of kidney stones is caused by the buildup of calcium oxalate.........

Posted by: Edwin      Permalink         Source


June 28, 2006, 0:08 AM CT

Improved Rating For Residential Fuel Cells

Improved Rating For Residential Fuel Cells
A new performance rating system for residential fuel cells developed at the National Institute of Standards and Technology (NIST) can help prospective buyers assess the economic value of alternative fuel-cell technologies.

Residential fuel cells now being developed combine hydrogen from natural gas or propane with oxygen from the air to produce electricity. Homeowners might be able to meet all of their energy needs with a residential fuel cell and, in some cases, even sell excess energy to a utility. Currently, PTC 50, an ASME standard, is used to measure fuel cell system performance, but it does not take into account either seasonal changes in heating and cooling requirements, or a residence's quickly changing demands for electricity.

To bridge the gap between the PTC 50 standard and the information that consumers will need to make economic decisions on installing a fuel cell, NIST scientists have published proposed test and rating methods* that will help consumers assess the economic feasibility of four different types of residential fuel cells under different climate conditions in six different geographic locations. The rating will provide the annual electrical energy produced, fuel consumed, thermal energy for domestic water heating and space heating delivered, and water used by the residential fuel cell system.........

Posted by: John      Permalink         Source


June 26, 2006, 11:21 PM CT

Kestrel 4000 Pocket Wind Meter

Kestrel 4000 Pocket Wind Meter
I have to admit this is the best weather gadget i've seen so far. It's an awesome-fully-packed Kestrel 4000 Pocket Weather Meter Station. It could now measure every major environmental condition, easily, and accurately right in your hand. The chart mode allows users to recall and graph up to 2,000 measurements, along with the date and time of storage. You can even check the current Wind speeds, temperature for air/water/snow, Wind chill, Bew point, Heat stress Index, Barometic pressure, Density altitude, and Wet bulb temperature. The flip-top impeller cover allows use of other functions while protecting the impeller. If you happen to drop it and spoilt the impeller, you can change it without any tools.

You can choose between automatic store measurement upon shut off or manually store measurements with the press of a button. The advanced thing is it has exterior temperature, humidity and pressure sensors for fast and accurate readings. The humidity sensor can be recalibrated in the field with their "Relative Humidity Calibration Kit". No matter where you go, jungle tracking, diving or even flying, you wont need to worry about the "toughness-ity" of Kestrel 4000, it's waterproof and it floats! You can always use the included neck and wrist lanyards to make sure it won't let go from your side. Powered by two AAA batteries, i got only one word for this little-muscular-guy, PERFECT!........

Posted by: John      Permalink         Source


June 26, 2006, 8:36 PM CT

Vega's Second Stage Motor

Vega's Second Stage Motor Artist’s impression of the Vega launch vehicle climbing through the Earth’s atmosphere.
Credits: ESA - J. Huart
ESA's Vega small satellite launch vehicle has made a new step toward its maiden flight, late next year, with the success of the first firing test on its second stage motor, the Zefiro 23.

The static firing waccording toformed today, 26 June, at the Italian Ministry of Defence test centre in Salto di Quirra, Sardinia. The 7.5m tall, 2m diameter motor, featuring a carbon epoxy filament wound casing, delivered more than 100 metric tons of thrust (1,070 kN), burning some 24 metric tons of solid propellant in 75 seconds.

Numerous data were gathered during the test and are now under analysis to improve technical knowledge of the motor's behaviour and refine the launcher's future performance. Also tested during the firing were various subsystems, including a thrust vector control system that will steer the motor's nozzle to provide flight control. After this success, the motor will proceed with its critical design review, at which stage its technical characteristics will be finalised.

Built by Avio in Colleferro, near Rome, the Zefiro 23 motor will be the basis for the second stage of ESA's Vega launcher. The first firing test with the third stage motor - the Zefiro 9 - waccording toformed in December 2005. Conducted on behalf of ESA's Vega development programme, these two firing tests followed three static firings of the Zefiro 16 demonstrator in 1998, 1999 and 2000. Both the Zefiro 23 and Zefiro 9 will undergo an additional ground firing test each to complete their development and qualification.........

Posted by: Edwin      Permalink         Source


June 26, 2006, 8:14 PM CT

Stealth Radar System Sees Through Trees, Walls

Stealth Radar System Sees Through Trees, Walls Eric Walton
Ohio State University engineers have invented a radar system that is virtually undetectable, because its signal resembles random noise.

The radar could have applications in law enforcement, the military, and disaster rescue.

Eric K. Walton, senior research scientist in Ohio State's ElectroScience Laboratory, said that with further development the technology could even be used for medical imaging.

He explained why using random noise makes the radar system invisible.

"Almost all radio receivers in the world are designed to eliminate random noise, so that they can clearly receive the signal they're looking for," Walton said. "Radio receivers could search for this radar signal and they wouldn't find it. It also won't interfere with TV, radio, or other communication signals".

The radar scatters a very low-intensity signal across a wide range of frequencies, so a TV or radio tuned to any one frequency would interpret the radar signal as a very weak form of static.

"It doesn't interfere because it has a bandwidth that is thousands of times broader than the signals it might otherwise interfere with," Walton said.

Like traditional radar, the "noise" radar detects objects by bouncing a radio signal off them and detecting the rebound. The hardware isn't expensive, either; altogether, the components cost less than $100.........

Posted by: John      Permalink         Source


June 24, 2006, 11:59 PM CT

Diamond As A By-Product

Diamond As A By-Product
There may not be a pot of gold at the end of the rainbow, but there appears to be nanocrystalline diamonds at the end of a process to produce and store hydrogen using anthracite coal.

"The idea we explored was based on ball milling graphite processes found in the hydrogen storage literature," said Angela D. Lueking, assistant professor of energy and geoenvironmental engineering. "We substituted anthracite coal for graphite because it is abundant and inexpensive. Now, with 20/20 hindsight, we are struck by the fact that coal gasification is currently the most economical way to produce hydrogen".

Interest in hydrogen as a vehicular fuel has many researchers investigating ways to create hydrogen inexpensively; other researchers are looking at ways to transport and store hydrogen in a safe manner. Lueking's group was exploring a way to store hydrogen in carbon-based materials, and inadvertently stumbled upon a method that combines production and storage and produces nanocrystalline diamonds as a by-product.

Lueking and colleagues, who included Humberto R. Gutierrez, post doctoral fellow in physics; Dania A Fonseca, post doctoral fellow in the Penn State Energy Institute; Deepa L. Narayanan, Dirk Van Essendelft and Puja Jain, graduate students in energy and geoenvironmental engineering and Caroline E. B. Clifford, research associate, Energy Institute, ball milled powdered anthracite coal with cyclohexene. Ball milling involves mixing a slurry of anthracite powder and cyclohexene with small steel balls and mixing so that the steel balls pound the coal particles and the cyclohexene causing physical and chemical changes. The researchers reported their results in a recent online issue of the Journal of the American Chemical Society.........

Posted by: John      Permalink         Source


June 24, 2006, 11:43 PM CT

Discovery Set For July 1 Launch

Discovery Set For July 1 Launch
The Space Shuttle Discovery and its crew are set for a July 1 flight to the International Space Station. The STS-121 mission will visit the International Space Station and continue evaluating new shuttle safety improvements. At least two spacewalks are planned during the 12-day mission, which also includes repair work to the station.

NASA managers gave the green light after a lengthy Flight Readiness Review held June 16-17, a traditional meeting in which top NASA managers and engineers set launch dates, determine whether the shuttle's complex array of equipment, support systems and procedures are ready for flight and assess any risks associated with the mission.

NASA senior managers on Saturday cleared the Space Shuttle Discovery for a July 1 flight to the International Space Station.

The decision was announced after a lengthy Flight Readiness Review, a traditional meeting in which top NASA managers and engineers set launch dates, determine whether the shuttle's complex array of equipment, support systems and procedures are ready for flight and assess any risks associated with the mission.

"We had two full days of an intensive Flight Readiness Review," said Administrator Michael Griffin. "It was spirited and one of the most open, yet non-adversarial meetings I've seen since returning to NASA".........

Posted by: Edwin      Permalink         Source


June 22, 2006, 7:23 PM CT

Intel's Tri-Gate Transistor

Intel's Tri-Gate Transistor
Intel Corporation scientists today disclosed they have developed new technology designed to further extend the company's leadership in energy-efficient performance.

Intel's research and development involving new types of transistors has resulted in further development of a tri-gate (3-D) transistor for high-volume manufacturing. Since these transistors greatly improve performance and energy efficiency Intel expects tri-gate technology could become the basic building block for future microprocessors sometime beyond the 45nm process technology node.

Planar (or flat) transistors were conceived in the late 1950s and have been the basic building block of chips since the dawn of the semiconductor industry. As semiconductor technology moves deeper into the realm of nanotechnology (dimensions smaller than 100nm), where some transistor features may consist of only a few layers of atoms, what was previously thought of as "flat" is now being designed in three dimensions for improved performance and power characteristics. Intel, leading the industry in producing high volumes of ever smaller chip geometries, has created a way to use these three-dimensional, or tri-gate, transistors in concert with other key semiconductor technologies to enable a new era of energy-efficient performance.........

Posted by: John      Permalink         Source


June 22, 2006, 7:12 PM CT

When Robots Learn Social Skills

When Robots Learn Social Skills
Learning to communicate and adapting our behaviour to the information we receive has been fundamental to human evolution. If machines could do the same the intelligent talking robots of science fiction could become the stuff of science reality, as scientists aim to prove.

Most research into the Artificial Intelligence (AI) that underpins any form of intelligent machine-machine or machine-human interaction has centred on programming the machine with a set of predefined rules. Scientists have, in effect, attempted to build robots or devices with the communication skills of a human adult. That is a shortcut that ignores the evolution of language and the skills gained from social interaction, thereby limiting the ability of AI devices to react to stimuli to within a fixed set of parameters.

But a team of scientists led by the Institute of Cognitive Science and Technology in Italy are taking a new approach to the problem, developing technology to allow machines to evolve their own language from their experiences of interacting with their environment and cooperating with other devices.

"The result is machines that evolve and develop by themselves without human intervention," explains Stefano Nolfi, the coordinator the ECAgents project, which, with financing from the European Commission's Future and Emerging Technologies (FET) initiative, has brought together scientists from disciplines as diverse as robotics, linguistics and biology.........

Posted by: John      Permalink         Source


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