Shigenori Okubo was born on May 13,1947. He received the B.E.degree in Electronic Engineering from Tohoku University,Japan,in 1970. He received the M.E,and the Ph.D. degrees in Mathematical Engineering and Applied Physics from The University of Tokyo,Japan,in 1972,and 1975,respectively. He entered Mitsubishi Electric Company Limited in 1975. He was a lecturer from 1980 to 1987,and an associate professor from 1987 to 1988 in The University of Tokyo. He was an associate professor from 1988 to 1990 in Yamagata University,Japan. He has been a professor since 1990 in Mechanical System Engineering, Graduate School of Engineering and Science,Yamagata University.