2012年6月19日 星期二

スパコン「京」世界一から転落 The K computer/Abnormal patterns on clam shells


スパコン「京」世界一から転落 米「セコイア」が首位に


理化学研究所と富士通が共同開発したスーパーコンピューター「京(けい)」が、18日に発表された計算速度の世界ランキングで2位となり、昨年6月 以来の世界一の座から転落した。1位は米国の「セコイア」で、計算速度は京の約1.5倍となる毎秒1京6324兆回(京は1兆の1万倍)。日本は7年ぶり に手にした首位を、1年でスパコン大国に奪われた。




Japan back on top in supercomputer race


photoThe K computer is being hailed as the world's fastest number cruncher. (Provided by RIKEN)

Japan has claimed the supercomputing crown for the first time in seven years with a machine being jointly developed by Fujitsu Ltd. and the government-affiliated RIKEN research institute.
Called the K computer, the machine topped the list of the world's 500 fastest computers released on June 20. The last time a Japanese supercomputer grabbed the title was in 2004, when NEC Corp.'s Earth Simulator turned in the fastest performance score in the world.
The K computer is far faster than rivals, boasting more than three times the number-crunching power of the previous holder of the title, China's Tianhe-1A, which was ranked second in the latest list.
The 112-billion-yen ($1.4 billion) project to develop the supercomputer, now housed at the RIKEN Kobe Institute, started in 2006.
The name of the machine comes from the Japanese word "Kei," which means 10 peta, or 10 quadrillion (10,000 trillion), reflecting the project's goal of creating a supercomputer that can make 10 quadrillion calculations (floating-point operations) per second, or, in computer science jargon, 10 petaflops.
With powerful players from the United States, Europe and China locked in ever-fiercer competition to develop faster computers, Japan's bid to reclaim the lead in the race was regarded with much skepticism at home.
During a budget review in November 2009, Renho, minister in charge of government revitalization, grilled both RIKEN and the Ministry of Education, Culture, Sports, Science and Technology over the supercomputer project by famously saying, "Why can't we just be content with being No. 2?"
The K computer, which is slated to be completed next summer, sped to the front of the class by reaching more than 8 quadrillion calculations per second, even though it can currently only operate at 80 to 90 percent of its expected capacity.
The rankings for the world's fastest computers are compiled and announced twice a year by a group of researchers in the United States and other countries.
Besides the RIKEN-Fujitsu machine, Tsubame 2.0 of the Tokyo Institute of Technology made it to the top five, ranked fifth.
In the previous rankings, announced in November last year, Tianhe-1A became the first Chinese supercomputer to claim to be the fastest on Earth.
The K computer's achievement is a big success for Japan, Jack Dongarra, a professor of electrical engineering and computer science at the University of Tennessee, told The Asahi Shimbun. Dongarra leads the group of researchers who compile the "Top500" supercomputing list.
Supercomputers are essential tools for a wide range of heavy-duty processing tasks, including military research such as simulations of nuclear explosions.
During the seven years after Japan's Earth Simulator was dethroned, American-made computers dominated the top ranks.
The United States remains the leading supercomputing power, accounting for more than half of the 500 fastest machines.
As supercomputing technology advances, the world's computing records are broken frequently.
In 2009, RIKEN requested an additional 11 billion yen to build new manufacturing lines in an attempt to gain a competitive advantage by completing the K project ahead of schedule.
But government policymakers involved in a budget-cutting campaign rejected the request.
When the research institute didn't get the additional funding, scores of renowned Japanese scientists bitterly criticized the government.
As a result, RIKEN was allowed to use the 18.3 billion yen earmarked for fiscal 2011 ahead of time. This helped quicken the pace of the development of the supercomputer, resulting in the victory.
The state-funded 112-billion-yen project is expected to produce a system useful for a wide range of real world applications, including weather forecasting and drug development.
At a June 20 joint news conference by RIKEN and Fujitsu, Kimihiko Hirao, head of the RIKEN Advanced Institute for Computational Science, said the K supercomputer can be used to mitigate disaster damage by running simulations of earthquake-caused tsunami. "It will play an important role in areas of applications where Japan has competitiveness," he added.
Japan's supercomputing supremacy may be short-lived, with U.S. rivals now developing several machines designed to outperform the K computer in an effort to take back the title as early as next year.
But the really important test for a supercomputer is how it is used to bring beneficial changes to our society and lives, not its simple calculation power.
Satoshi Matsuoka, a professor at the Tokyo Institute of Technology who developed Tsubame 2.0, the No. 5 supercomputer, said: "It is not that we have just created a big machine. Since our application programs (run on the machine) have demonstrated extremely high performances, we are expecting to make some breakthroughs."
(This article was written by Ryoma Komiyama and Masanobu Higashiyama.)

Abnormal patterns on clam shells a sign of stress from tsunami


photoNormal clam shells, above, and ones showing changes in patterns (Provided by Kenji Okoshi)
Even hardy marine creatures are showing signs of stress from the disastrous effects of the March 11 Great East Japan Earthquake.
Abnormal shell patterns have been found on clams off the coast of Fukushima Prefecture since the tsunami radically changed their habitat, according to research team led by Kenji Okoshi, a professor of environmental dynamic analysis at Toho University.
Okoshi's team studied the density of clams in their habitats and other changes in May at Matsukawaura bay and inlets in Soma, Fukushima Prefecture. These areas are noted for their clam cultivation.
Of the 216 clams studied, 192, or about 90 percent, had ruts in the middle of their shells. The ruts marked the start of different colors and patterns leading toward the edges, the team said.
In contrast, a survey conducted in June 2009 in Matsukawaura bay found only 10 percent of the clams showed changes in their shells, such as parallel striations.
Okoshi said the latest clams likely came under great stress due to the long distances carried by the tsunami, the sudden change in salt concentration, and the unnatural mix of sand and mud in the seabed.
Okoshi added, "This phenomenon itself won't necessarily affect the taste and quality of the clams."