Japanese Computer Is World's Fastest, as U.S. Falls Back The world's fastest computer A Japanese laboratory has built the world's fastest computer, a machine so powerful that it matches the raw processing power of the 20 fastest American computers combined and far outstrips the previous leader, an 1. B. M. -built machine. The achievement, which was reported today by an American scientist who tracks the performance of the world's most powerful computers, is evidence that a technology race that most American engineers thought they were winning handily is far from over. American companies have built the fastest computers for most of the last decade. The accomplishment is also a vivid statement of contrasting scientific and technology priorities in the United States and Japan. The Japanese machine was built to analyze climate change, including global warming, as well as weather and earthquake patterns. By contrast, the United States has predominantly focused its efforts on building powerful computers for simulating weapons, while its efforts have lagged in scientific areas like climate modeling. A competition between Japan and U. S. For some American computer scientists, the arrival of the Japanese supercomputer evokes the type of alarm raised by the Soviet Union's Sputnik(人造地求卫星)satellite in 1957. Several United States computer scientists said the Japanese machine reflected differences in style. and commitment that suggest that United States research and spending efforts have grown complacent (自满的)in recent years. For now, the new computer will be used only for climate research, and American scientists have already begun preparing to move some of their climate simulation research to run on the Japanese machine. 'The Japanese clearly have a level of will that we haven't achieved,' said Thomas Sterling, a computer designer at the California Institute of Technology. 'These guys are blowing us out of the water, and we need to sit up and take notice.' Wide applications of the magic power The new Japanese supercomputer will have both scientific and practical applications. It will be used for advanced modeling of theories about global warming and climate change, and it will be able to predict short-term weather patterns. Advances in computer speed today routinely extend computer simulation into all areas of science and engineering as complex calculations take an increasingly shorter time. Because increases in computing power tend to have exponential (指数的)results, a problem that could take years for even the fastest computers today might be finished in hours on the new Japanese computer. The ability to track the path of a typhoon, for example, is of immediate relevance to the island nation of Japan. Improved prediction made possible by a more powerful computer might save lives and property. Computer simulation has become a standard tool in both science and modern design of products ranging from drugs to bicycles. Computers that are more powerful make possible simulations that are more accurate and can reduce cost and increase efficiency. At one time, for example, computers were capable of computing the flow of air over a single airplane wing but can now cover the entire aircraft. The new Japanese supercomputer was financed by the Japanese government and has been installed at the Earth Simulator Research and Development Center in Yokohama (横滨), west of Tokyo. The Japanese government spent $ 350 million to $ 400 million developing the system over the last five years, according to Dr. Akira Sekino, president and chief executive of HNSX Supercomputers, a unit of the NEC Corporation based in Littleton, Colo. The new computer was formally dedicated last month, and the Japan Marine Science and Technology Center said yesterday that the mac