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Space

Submission + - Mysterious Sound Waves Can Destroy Rockets

Submitted by
Ponca City, We love you
Ponca City, We love you writes: "Scientists believe that powerful and unstable sound waves, created by energy supplied by the combustion process, were the cause of rocket failures in several US and Russian rockets and have also observed these mysterious oscillations in other propulsion and power-generating systems such as missiles and gas turbines. Now, researchers at the Georgia Institute of Technology have developed a liquid rocket engine simulator and imaging techniques to help demystify the cause of these explosive sound waves and bring scientists a little closer to being able to understand and prevent them. The team was able to clearly demonstrate that the phenomenon manifests itself in the form of spinning acoustic waves that gain destructive power as they rotate around the rocket's combustion chamber at a rate of 5,000 revolutions per second. Researchers developed a low-pressure combustor to simulate larger rocket engines then used a very-high-speed camera with fiber optic probes to observe the formation and behavior of excited spinning sound waves within the engine. "This is a very troublesome phenomenon in rockets," said Professor Ben Zinn. "These spinning acoustic oscillations destroy engines without anyone fully understanding how these waves are formed. Visualizing this phenomenon brings us a step closer to understanding it.""
Privacy

Movement Sensors a Less Invasive Alternative To CCTV 103

Posted by kdawson from the sees-you-when-you're-moving dept.
holy_calamity writes "Researchers at Mitsubishi say cramming buildings with movement sensors, not cameras, is a safer and less invasive alternative to CCTV. They covered their office building with 215 low-cost sensors to watch over their colleagues and show how it works. A video shows how a user can see people's movements on a map of the building in real time. Data from the sensors is much easier to handle than video footage, and it can easily be searched." The Surface-like UI is pretty neat too.
The Internet

eBay Australia Makes PayPal Mandatory 390

Posted by samzenpus from the what-about-dubloons dept.
An anonymous reader writes "Australian press are reporting that eBay is using Australia as a guinea pig to trial a new policy where all other modes of payment are barred except for PayPal. If successful, eBay will roll it out to other markets."
Businesses

Climate Change Finally Impacts Important Industry 405

Posted by CmdrTaco from the mmmmmmm-beer dept.
Socguy writes "According to a New Zealand scientist, Jim Salinger, the price of beer in and around Australia is going to be under increasing upward pressure as reductions in malting barley yields are experienced as a side effect of our ongoing climate shift. "It will mean either there will be pubs without beer or the cost of beer will go up," Mr. Salinger told the Institute of Brewing and Distilling convention."
Power

The Texas Petawatt Laser 174

Posted by kdawson from the you-can-pet-a-dog-or-you-can-pet-a-cat dept.
Roland Piquepaille notes the hype surrounding what the University of Texas at Austin is calling the world's most powerful laser. During a tenth of a femtosecond this laser is 2,000 times more powerful than all the power plants in the US, and is brighter than sunlight on the surface of the Sun. On his own blog Roland points out that UT's is not the first petawatt laser; that distinction belongs to a system installed at Lawrence Livermore National Laboratory in 1996.
Space

Meteorites May Have Delivered Seeds of Life On Earth 277

Posted by Zonk from the thanks-for-the-lift dept.
esocid writes "At the national meeting of the American Chemical Society, scientists presented evidence today that desert heat, a little water, and meteorite impacts may have been enough to cook up one of the first prerequisites for life. The result of that brew could be the dominance of "left-handed" amino acids, the building blocks of life on this planet. Chains of amino acids make up the protein found in people, plants, and all other forms of life on Earth. There are two orientations of amino acids, left and right, which mirror each other in the same way your hands do. These amino acids "seeds" formed in interstellar space, possibly on asteroids as they careened through space. At the outset, they have equal amounts of left and right-handed amino acids. But as these rocks soar past neutron stars, their light rays trigger the selective destruction of one form of amino acid."
The Internet

pizza.com Sold For $2.6m 243

Posted by CmdrTaco from the meanwhile-people-are-losing-their-homes dept.
f8d noted a beeb bit on the fact that the pizza.com domain name was sold for a ridiculous 2.6m bucks. Can there be a bubble and a recession at the same time, or do the two cancel each other out like Penn & Teller?

Comment Re:not gonna work (Score 1) 196

by OneTweezyStyle (#22966042) Attached to: Identify and Verify Users Based on How They Type
I feel that the idea has some merit. It has occurred to me on a few separate occasions that the pattern of my keystrokes when entering passwords is highly consistent after a brief period of acclimation to the new password. I could easily see the pattern of keystrokes being used as an additional verification factor. Much as with other forms of verification having a biological basis, I can foresee a few potential issues (e.g. the voice recognition system at my firm doesn't recognize me when I have a "cowde"). For example, what happens when I get a new keyboard, or log in from a terminal with a different keyboard?
Science

Daily Caffeine Protects Your Brain 325

Posted by samzenpus from the it's-what-brains-crave dept.
Chroniton writes "The BBC has a story that many Slashdot geeks will be happy to hear: the caffeine from a cup of coffee a day can help prevent Dementia, by blocking the damage of cholesterol. (At least in rabbits) This is in addition to the already-known protection against Alzheimer's Disease. More research is needed to test the effect on humans."

Will Twitter Join Podcasting on the 'Net Sidelines'? 221

Posted by CmdrTaco from the no-i-need-to-know-the-minutia-of-everyone's-day dept.
Ian Lamont writes "Twitter has established itself in some quarters as a must-have communications tool, and its power to connect and even incite people is hard to deny. But does Twitter have long-term, mainstream potential? Or does a poor revenue model and strong competition mean that it's destined to be a sideline Internet technology, much like podcasting has failed to live up to early hype?"
United States

Submission + - US IP hypocrisy: ignoring unwelcome WTO rulings (arstechnica.com) 2

Submitted by Eye Log
Eye Log writes: The United States is a big fan of leaning on other countries to tighten IP and copyright protection, but has a tendency to ignore its own obligations when it doesn't get its way. 'Two ongoing cases illustrate the point. First, the European Union is pushing for the US to change a pair of rules that it calls "long-standing trade irritants." Despite World Trade Organization rulings against it, the US has not yet corrected either case for a period of several years... Apparently, it's easy to get hot and bothered when it's industries from your country that claim to be badly affected by rules elsewhere. When it comes to the claims of other countries, though, even claims that have been validated by the WTO, it's much easier to see the complexity of the situation, to spend years arguing those complexities before judges, and to do nothing even when compelled by rulings.'
Wireless Networking

City-Provided Wi-Fi Rejected Over "Health Concerns" 360

Posted by kdawson from the just-put-on-the-tinfoil-hat-and-it-will-be-all-better dept.
exphose writes "A small, hippie-friendly town in northern California, Sebastopol, had made an agreement with Sonic.net to provide free Wi-Fi across the downtown area. However, not everyone in town was pleased with the arrangement. According to Sebastopol Mayor Craig Litwin, citizens had voiced concerns that 'create enough suspicion that there may be a health hazard' and so they canceled their contract with Sonic.net. Some more details are at the blog of Sonic.net's CEO."
Sun Microsystems

Sun Turns to Lasers to Speed Up Computer Chips 130

Posted by ScuttleMonkey from the friggin-lasers dept.
alphadogg writes to mention that Sun is attempting to move from the typical design of multiple small chips back to a unified single-wafer design. "The company is announcing today a $44 million contract from the Pentagon to explore replacing the wires between computer chips with laser beams. The technology, part of a field of computer science known as silicon photonics, would eradicate the most daunting bottleneck facing today's supercomputer designers: moving information rapidly to solve problems that require hundreds or thousands of processors."
Social Networks

Lessig Bets On the Net To Clean Up Government 126

Posted by kdawson from the change-congress dept.
christian.einfeldt writes "Stanford Law Professor Larry Lessig really 'gets it' when it comes to the efficacy of distributed open source code production. Now he is attempting to use distributed production methods to expose corruption in the US Congress with the launch of another 'CC' organization — this time it's called 'Change Congress'. CC (as opposed to cc for Creative Commons) would invite users to track whether US legislators are willing to commit to Change Congress' four pledges. CC will rely on users to record and map the positions of candidates who are running for open seats in the US House and Senate. Change Congress will use a Google mash-up to create a map depicting which legislators have taken the CC pledge, which have declined, and which have signaled support for planks in the Change-Congress platform. The four pledges (which are not numbered 0 through 3) call for greater transparency in government, and less influence of private money in shaping legislation."
Medicine

"Manhattan Project" For Prosthetic Arms 76

Posted by Soulskill from the kinder-gentler-arms-race dept.
cortex tips us to a story about a nationwide effort to incorporate advanced technology into the next generation of prosthetic arms. Researchers for the DARPA-funded project are developing feedback techniques that range from sensors on the surface of the user's skin to electrodes implanted on the inside of the user's skull that intercept and interpret signals from the motor cortex. Quoting: "'Think about taking a sip from a can of soda,' Harshbarger says. The complex neural feedback system connecting a native limb to its user lets that user ignore an entire series of complicated steps. The nervous system makes constant automatic adjustments to ensure, for example, that the tilt of the wrist adjusts to compensate for the changing fluid level inside the can. The action requires little to no attention. Not so for the wearer of current prosthetic arms, for whom the act of taking a sip of soda precludes any other activity. The wearer must first consciously direct the arm to extend it to the correct point in space, then switch modes to rotate the wrist into proper position. Then he must open the hand, close it to grasp the soda can (not so weakly as to drop it but not so hard as to crush it), switch modes to bend the elbow to correctly place the can in front of his mouth, rotate the wrist into position, and then concentrate on drinking from the can of soda without spilling it."

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