Eagan based Cray Research, a division of Silicon Graphics, says it will speed the development of its supercomputers to better simulate nuclear explosions. The federal government has awarded a five million dollar contract to Cray Research, as part of a program to ensure the safety of the country's nuclear stockpile. Mark Goldman, director of business strategy for Cray Research, says today's supercomputers aren't powerful enough to do what the government needs them to do.