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New NASA Rocket Has Vibration Problems

Over the weekend, we learned the U.S. space agency's new rocket for the next generation of space vehicles has a design problem that could seriously undermine its progress. Still on the drawing board, the proposed Ares class of main propulsion engines has an engineering flaw that will most likely lead to severe vibrations upon launch, according to a report from the Associated Press.

The new Ares rockets are being developed to lift the spacecraft that will replace the shuttle into orbit. They are designed to take advantage of successful technology modified from the shuttle program and are officially designated as Shuttle-Derived Launch Vehicle prototypes. NASA plans to use them to return to the Moon by the year 2020--and keep on going from there to Mars ultimately.

Relying on solid-fuel engines, the first of their class, Ares I, is to be the rocket that will serve to propel the astronauts onboard the proposed Orion crew launch vehicle into space. Engineers are now pointing out that the current design of the Ares I shows flaws in the use of the first-stage solid rocket boosters (SRBs) that could lead to significant shaking of the units, possibly transmitting vibrations up the rocket. Should the vibration problem be severe enough during ascent to cause damage to the upper stages of the craft, it could prove to be catastrophic.

Reached by the AP after it had learned of the flaw through a Freedom of Information Act petition, NASA managers said they were fully aware of the problem and expected to have it fixed by as early as March, posing no delay to the overall schedule of the pending Project Constellation program.

"I hope no one was so ill-informed as to believe that we would be able to develop a system to replace the shuttle without facing any challenges in doing so," Administrator Michael Griffin said in a statement to the AP. "NASA has an excellent track record of resolving technical challenges. We're confident we'll solve this one as well."

One of the outside experts recruited by the news service to examine the design of the Ares I agreed with others that the SRBs' tendency to vibrate at lift-off posed a serious hazard, but he was also confident that NASA would be able to overcome it.

"NASA has developed one of the safest and risk-controlled space programs in engineering history," Professor Jorge Arenas of the Institute of Acoustics in Valdivia, Chile, told the AP.

As the report explains:

The shaking problem, which is common to solid rocket boosters, involves pulses of added acceleration caused by gas vortices in the rocket similar to the wake that develops behind a fast-moving boat, said Arenas, who has researched vibration and space-launch issues. Those vortices happen to match the natural vibrating frequencies of the motor's combustion chamber, and the combination causes the shaking.

The SRBs for the Ares I are being built by ATK Launch Systems of Brigham City, Utah.

The first launch of the Ares I to carry astronauts into space is scheduled for March 2015.

That gives NASA a good size window to make sure every possible bug in the system has been identified and eliminated. Historically, it is an agency that understands just how much is at stake.

Road blocks on the hydrogen highway

master_map-N_05022007_02.jpgRemember the â''hydrogen highway?â'' This was California Governor Arnoldâ''s Schwarzeneggerâ''s vision back in 2004. He proclaimed that, by 2010, California highways would be lined with hydrogen fueling stations, some 20 miles apart throughout the state, enabling hydrogen-powered cars and buses to travel freely. He signed an executive order setting up a private and public partnership to implement that vision.

2010 is almost here, and it hasnâ''t exactly worked out. (We didnâ''t think it would; IEEE Spectrum called the effort a â''loserâ'' in its January 2004 issue.) At its peak in 2006, the state had 24 stations; now it has 23, next month that number is expected to drop to 22 when PG&E closes a San Francisco station. While a few new ones opened, a few also closed. And several planned were never built. The California Air Resources Board agreed to spend about $1 million each to fund stations built by the San Diego Unified School District and the California State University-Los Angeles; both projects fell through. And PG&E just turned down $1.5 million to build a hydrogen refueling station in San Carlos.

The Air Resources Board hasnâ''t given up; itâ''s putting out a call for proposals for a total of $7.7 million of funding already set aside for new hydrogen fuel stations or upgrades. And the new state budget asks for $6 million more for such projects. But will there be any takers?

Out of Africa: a new model for academic computer science

Newly-minted PhDs in computer science flock to Silicon Valley or other information-technology centers around the world. John Quinn had a different idea of how to pursue a scientific career. A Scot from Inverness, Quinn received his doctorate in computational analysis from the University of Edinburgh last year. His specialty is how computers recognize patterns.

Concerned about the shortage of computer professors with PhDs at African universities, Quinn decided to join the faculty of one, forgoing a position at a university in Britain. After a brief tour, Quinn, who is 28 years old, chose the Computer and Information Technology department of Makerere University in Kampala, Uganda.

Makerere is in the forefront of a movement to improve computer science and electrical engineering departments in Africa. One part of the strategy is to attract talent from technologically advanced societies. The university attracted Quinn with a salary that approaches what heâ''d earn as a new faculty in Europe and a challenging teaching load that includes contributing to a new graduate program.

â''In CS, Makerere is becoming a serious competitor with South African universities,â'' generally considered to be the strongest in the region, Quinn says.

â''The program runs with great energy and optimism,â'' Quinn adds. Faculty camaraderie is high. Most gather daily for a 1 pm lunch. About a dozen of the professors hold a doctorate; the remaining 40-50 instructors hold only masterâ''s degrees or less. â''The environment is convivial,â'' he says.

To my knowledge, Quinn was the only European holder to obtain a new CS doctorate who then migrated to Africa to teach. He arrived in Kampala last September. â''Iâ''ve been delighted,â'' he says. â''It just doesnâ''t occur to computer academics to come to Africa to teach. Africa isnâ''t on the map.â''

Quinn is bullish that Makerere Universityâ''s Computer and Information Technology department will make Kampala one possible destination for other graduates of doctoral CS programs in Europe and the U.S. Quinn has already written two papers while at Makerere, one of which will be published in April, he says,. In IEEEâ''s International Conference on Acoustics. The paper is about how computers drown out, or mask, signals.

Besides his own research in pattern recognition, Quinn is trying to stimulate the dozen graduate students he mentors to craft their own research agendas. He expects to spend at least another two years at Makerere.

Quinn advises other CS academics in North America and Europe -- both inexperienced and veterans â'' to consider a stretch of teaching in sub-Saharan Africa. His advice?

â''Be prepared to deal with isolation,â'' especially while doing research, he says. He says that a taste for the style and serendipity of African life is also a plus.

NASA Wants Virtual World Designers for MMO

The U.S. space agency has placed a request for information (RFI) on its Web site for software developers interested in creating a massively multiplayer online (MMO) game for space enthusiasts. BBC News is reporting that the goal of the game they want to create is to reach young people interested in space exploration.

The MMO game the agency is seeking would "simulate real NASA engineering and science missions," according to the RFI. "A high quality synthetic gaming environment is a vital element of NASA's educational cyberstructure," it goes on to add.

"The MMO will foster career exploration opportunities in a much deeper way than reading alone would permit and at a fraction of the time and cost of an internship program."

The BBC article points out that NASA already is a player in the virtual worlds phenomenon, with its own base of operations in the highly popular game Second Life. The outpost, known as CoLab and operated by the Ames Research Center in California, is dedicated to fostering collaboration between the agency and those attracted to the space program.

"We at NASA are working hard to create opportunities for what I might call participatory exploration," the director of the project, Simon Worden, told delegates at the National Space Society's conference last year, according to the BBC report. "We are looking at how this island can be a portal for all to fly along on space missions."

"When the next people step onto the surface of the Moon in a little over a decade, your avatar could be with them," he added.

The RFI is an invitation to game specialists to become involved in a dedicated new MMO environment to be developed under the auspices of the NASA Learning Technologies Project Office. The deadline for submitting requests for participation is 15 February.

It states: "A NASA-based MMO could provide opportunities for students to investigate science, technology, engineering, and mathematics career paths while participating in engaging game play."

Now, all you advanced game developers out there have a really significant real-world challenge to rise to, one worthy of your amazing skills. Take 'em on. You could help explore really other worlds.

Scientists find a way to make airplanes "greener"

Lighten the weight of its wings and an airplane immediately becomes more fuel efficient. Researchers at Delft University in the Netherlands, along with collaborators at aluminium giant Alcoa and GTM Advanced Structures, have redesigned airplane wings so that they are made up like a sandwich. The central layer is a strong mesh of fibers laminated with metal; on either side lies a thick aluminium layer. Not only does this create a light, robust wing, the resulting structure is also insensitive to metal fatigue, which plagues wings made just of aluminium. Besides, the new wings are stronger than the carbon fiber reinforced plastic wings that have recently been used in aircraft such as the Boeing 787. The researchers estimate that using their new "green" design allows a weight reduction of about 20 per cent compared to the Boeing 787. They translate this to a worldwide fuel and maintenance savings of $100 billion for the airline industry.

 

 

 

Bobby Fischer Dies

 

 

 

 

Credit: Chris Lott

 

 

Robert J. Fischer has died, apparently of kidney failure, in Reykjavik, Iceland. This is the city where he had won fame in 1972 by defeating Boris Spassky to become World Chess Champion, the only American to do so in modern times. Three years later, Fischer refused to defend his title and became a recluse. He emerged only in 1992 to win a return match against Spassky, then long past his prime.

 

Because Fischer played that match in war-torn Yugoslavia, in defiance of a U.S. economic embargo, and because he refused to pay income taxes on the money heâ¿¿d won, he became a man without a country, sojourning in Hungary, the Philippines, Japan and other places. After September 11, 2001, he added insult to injury by cheering on al Qaeda, a move that may have induced U.S. diplomats to intensify their pursuit of him. He was run to ground in Japan in 2004, where he eluded extradition to the U.S. only at the last minute, when Iceland granted him citizenship and thus the right of domicile.

 

Many former fans, seeking to retain a shred of their image of Bobby, as he was universally known, excused his behavior on the ground heâ¿¿d lost his mind. The cited his frequent anti-Semitic outbursts, made though Fischerâ¿¿s late mother (and perhaps his father, as well) were themselves Jews. On the other hand, Fischer had been giving vent to such opinions since his adolescence. Also, although he had always shown signs of paranoia (which is not uncommon among grandmasters), his mind remained clear on the things that mattered to him.

 

Readers of this blog will be interested to know that in 1989 Fischer took out the patent for a computerized device, called the Fischer Clock, that has since changed the way the game is played. With each move completed, the clock adds a designated number of seconds to a playerâ¿¿s allotted thinking time, ensuring that no one need lose a clearly drawn position for sheer lack of time to physically make the moves. Fischer also patented FischerRandom chess, in which a computer sets up the initial position randomly (albeit under certain constraints). That way, no player can derive unfair advantage from pre-game opening preparation.

 

Both innovations were meant, in part, to counter the influence of computers on human players. Interestingly, the remedies themselves depend on computers. Spectrum has chronicled both the success of computer chess programs versus Gary Kasparov and what human players can do to try to fight back.

So much for his life. (It's also worth checking out Paul Hoffman's take on the chess hero) Now let me tell you what it meant to players like me. I got into the game as a freshman in high school, in 1969. That was just before Bobby, as he was universally known, had begun his final ascent to the championship. Suddenly, it was cool to play chess.

 

We players were proud that Fischer had won the respect of millions of non-players, from with President Nixon on down, and that his example had converted tens of thousands of people to the game. Such newbies swelled the tournament halls, raising prize funds to Las Vegas standards and enriching formerly threadbare masters. The â¿¿Fischer Boomâ¿¿ had begun.

 

I well remember the transformation of the chess club in my hometown of Chicago. When I first attended it, it was a second-floor dive in a dicey part of the Loop, defined by the curving route of the cityâ¿¿s elevated train, whose ear-splitting screech did not so much as register with the 50-odd men bending over their chessboards. After Fischerâ¿¿s success, the club removed to far plusher digs, in the LaSalle Hotel, where the resident masters at last began to eat and dress like human beings.

 

Then Bobby turned his back on the game, and the club faded again. When I visited it last, in 1978, it was in accommodations even worse than those it had started in. The few masters who still visited there looked hungry. Although the rest of the world continued to play chess, but in America it suffered a decline from which it is only now emerging.

 

It had all happened before, in the 1850s, when a 21-year-old Louisianian named Paul Morphy went to Europe and crushed its best players. Like Fischer, Morphy was without peer; he developed in isolation from the best players; he had an encyclopedic â¿¿bookâ¿¿ knowledge of the game; he was feted by the press and by the grandees of the day; he quit at the height of his fame; he exhibited signs of eccentricity verging on madness. Morphy, though trained as a lawyer, never practiced, but lived out his bachelor existence on an inheritance, refusing ever to speak of chess.

 

No such towering player can ever come again, for chess is no longer what it was. Fischer is part of the reason for the change, because he set a new standard that all serious players thenceforth had to meet. It was an inhuman regimen of work, which he began at the age of seven at the cost of school, family and friends. He would not allow himself even the smallest luxury if it interfered with his goals. Once, when a tournament sponsor offered him the hotel room with the best view, Fischer refused it in favor of a windowless cell.

 

â¿¿All I want to do, ever,â¿¿ he had said as a child, â¿¿is play chess.â¿¿ Gary Kasparov, todayâ¿¿s leading player, has called him â¿¿a centaur if you will, a synthesis between man and chess.â¿¿

 

Before Fischer, many world-class players had followed a professionâ¿¿Mikhail Botvinnik, world champion in the 1950s, was an electrical engineer; Max Euwe, champion in the late 1930s, was a mathematician. Todayâ¿¿s top players are players for as long as they hope to competeâ¿¿and nothing more.

 

A few years ago, Fischer derided todayâ¿¿s young grandmasters for their excessive reliance on computer chess programs and game databases, which allow a player to keep up with millions of games, including those played this morning in another part of the world. He joked that they all had to wear glasses because theyâ¿¿d spent so much time staring at computer screens. But Fischer would have done the same, only more so. As it was, he had one of the largest private chess libraries, and he subscribed to scores of chess journals in many languages, Russian above all.

 

Fischer did face a computer once. He played a Kingâ¿¿s Gambit against the MIT program and defeated it with ease; afterwards, he said computer chess would never get anywhere until chess masters began to work on the programs, alongside engineers. That was in 1978. Nineteen years later, Gary Kasparov lost a match against IBMâ¿¿s chess machine, Deep Blue, the first such machine to have been exhaustively tunedâ¿¿or trained?â¿¿by grandmasters.

 

Fischer was aged 64â¿¿the number of squares on a chessboard.

 

--P.R.

 

 

For other Spectrum articles about game-playing machines, see:

 

â¿¿Cracking Goâ¿¿ on efforts to defeat a still more complex game, from Asia.

 

and

 

â¿¿Checkers, Solved!â¿¿ on the proof that checkers, properly played, must always end in a draw,

Taser Use Leads to Another Fatality

While the stun gun has been immensely successful in lowering the number of fatalities in confrontations between law enforcement officers and those suspected of criminal behavior, its record is far from perfect. In recent times, use of the most popular brand of the weapon, the Taser, has created an ongoing controversy. Now, add another black mark to its record.

The Pioneer Press of Minneapolis/St. Paul reports that Minnesota State Patrol officers attempting to subdue an "uncooperative" motorist involved in a traffic accident yesterday used a Taser on him and that he subsequently died.

The fatality in Minnesota cannot as yet be attributed to use of the Taser (an autopsy is pending), but the circumstances seem to point in its direction. This undoubtedly will add more fuel to the debate over the role of stun guns in the administration of non-lethal force by the police.

Although "Don't tase me, bro!" made headlines in 2007 as the year's top quote in the "Yale Book of Quotations" for reasons that border on the farcical, there is nothing humorous about the recent string of deadly encounters in which a Taser was used by police and other officials in the exercise of their duties.

To investigate the safety of Taser use, this publication last month ran a feature on the controversial stun gun, "How a Taser Works". In it, Associate Editor Sandra Upson framed the debate as follows:

Even if Tasers are proven to be entirely safe, there's the bigger question of whether the stun guns encourage police brutality. A Taser shock leaves almost no visible scarring or bruising, as a clubbing or a beating typically would. Could the absence of physical scars lift a psychological restraint on officer behavior? Should every Taser gun have a built-in video camera?

Equipping law-enforcement services with Tasers is likely to reduce the number of bullets officers fire from their handguns and therefore the number of serious injuries and deaths. At the same time, it may lead police to inflict an unwarranted amount of pain on individuals who commit only minor crimes.

She then turned the podium over to two experts to share their knowledge of the weapon's use with our audience. Mark W. Kroll, an IEEE senior member who holds more than 250 U.S. patents and sits on the board of Taser International, looked at the problem from an engineering perspective. And Patrick Tchou, a cardiologist who specializes in treating cardiac rhythm disturbances at the Cleveland Clinic in Ohio, examined the matter from the biomedical point of view.

Whilw they could not resolve the debate over the relative safety of the Taser as a non-lethal deterrent in potentially dangerous circumstances, their insights are instructive.

The bottom line when it comes to the Taser in law enforcement, our authors suggest, is that much more research is needed. That may be a shopworn phrase when it comes to controversial technical topics, but it sounds like an earnest plea to fellow engineers, scientists, and doctors in this case. All of us should be interested in what such future research could reveal. It is, after all, a matter of life and death.

Computer scientists on the red carpet: Academy Awards recognize advances in fluid simulation

The upcoming 2007 Academy Awards, besides recognizing great actors and directors, are recognizing a few great computer scientists. Their award-winning opus? Fluid simulation.

On Feb 9th in Los Angeles, the Academy will present scientific and technical awards to Ron Fedkiw, a Stanford University professor, and Nick Rasmussen and Frank Losasso Petterson of Industrial Light & Magic (ILM) for the development of ILMâ''s Fluid Simulation System; and Doug Roble, Nafees Bin Zafar, and Ryo Sakaguchi at Digital Domain for the development of that companyâ''s Fluid Simulation System. All will receive Academy Plaques at a black tie event honoring the many scientists, engineers, and technicians who work behind the scenes in the movie industry.

Fedkiwâ''s work started a few years ago, in an effort to model the female liquid terminator in Terminator 3, and, soon after, simulated the wine drunk by the pirate skeleton in Pirates of the Caribbean. Fedkiw explained to Spectrum that the Navier-Stokes equations traditionally used to dictate how a fluid behaves are very complex, and when using them exclusively, limited computer resources can lead to errors. But when people look at water, they are seeing the surface, not its internal movement; the most important part of the model is not the fluid itself, but the interface between two fluids, water and air. Typically moviemakers donâ''t model the entire body of water, but rather focus on the fluid just below the surface; this is called the â''level setâ'' method. Fedkiwâ''s â''particle level setâ'' method instead uses some particles on each side of the surface, some air, some water. This information can correct errors made by the level set method, or, if those errors become too severe, take over as the main representation of the fluid. The particle set method turned out to be particularly useful for representing phenomena that are combinations of air and water, like spray and bubbles. The video above demonstrates the technique.

These days, Fedkiw is applying his approach, that is, developing new techniques for tying together disparate physical phenomena, to new problems: like the

coupling of highly rigid and highly deformable substances, for example, where flesh meets bone in the human body.

â''While good methods for simulating bones and joints exist, and likewise for soft tissue and muscle, typical simulations calculate skeletal motion first and then the skeleton drives the outer deformable layer without feedback,â'' says Fedkiw. â''That is, if you punched a simulated human in the stomach, it would not cause the skeleton to bend over.

â''Working on this problem for the last five years with zero progress has felt like being punched in the gut.â''

Last year, Fedkiw says, â''One lucky afternoon it all made sense.â'' He and his graduate students have been designing simple creatures that interact with each other and the environment, like snakes and worms. Theyâ''re also working on simulating the interaction between solids and fluids, like cloth being dipped in water. Combining the two projects, theyâ''ve simulated a fish with an internal bone structure flopping around in water. Theyâ''ll be trying that with a simulated human next.

Life-building organic molecules found in a distant galaxy

Astronomers from Arecibo Observatory in Puerto Rico have found the organic molecules hydrogen cyanide and methanimine in Arp 220, a galaxy that lies about 250 million light years away. The discovery is noteworthy because the two molecules are among the basic ingredients of life. When methanimine and hydrogen cyanide are combined with water, the amino acid glycine is formed. This is the farthest ever that these molecules have been seen. The astronomers chose Arp 220, an ultra-luminous galaxy, because it seems to be forming new stars at a very high rate. They used the 305-metre diameter Arecibo radio telescope, the world's largest and most sensitive, to observe the galaxy at different frequencies. Different molecules have unique radio frequencies associated with them, much like human beings have unique fingerprints.

"The fact that we can observe these substances at such a vast distance means that there are huge amounts of them in Arp 220," said Emmanuel Momjian, a former Arecibo astronomer, now at the National Radio Astronomy Observatory in Socorro, New Mexico. "It is indeed very intriguing to find that the ingredients of life appear in large quantities where new stars and planets are born."

CES Video Highlights: Bug Labs Lets You Build Your Own Gadget

Even though they had a tiny booth at CES, Bug Labs seemed to strike a nerve. In addition to winning CNET's Best of CES Award for emerging technologies, the Bug team excited the crowd with the promise of one gadget to replace the ever increasing menagerie of devices on exhibit elsewhere at the show. Steven Cherry has already discussed why open source hardware is so revolutionary, but its best to just see the Bug for yourself. We talked first to Mehrshad Mansouri, who gave an overview of the device and showed off some of its initial possibilities:

Next up was Bug Labs' Jeremy Toeman, who explained how the bug base, modules, and software actually work together, and what sort of engineering challenges faced the team:

The Bug may not be the smallest or most attractive device out there, but it's as close as you'll come to one that's future proof. Do you think open source gadgets can become as successful as open source software? Let us know what you'd want your dream gadget to be able to do.

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