He has held faculty/research positions at Osaka University, Japan; IBM T. J. Watson Research Center, Yorktown Heights, NY; the Naval Postgraduate School, Monterey, CA; and Kyushu Institute of Technology, Iizuka, Japan. Now, he is a Professor at the Department of Computer Science, Meiji University, Kawasaki, Japan.
His research areas include logic design and switching theory, representations of logic functions, and multiple-valued logic.
He has published more than 9 books on logic design including, Logic Synthesis and Optimization, Representation of Discrete Functions, Switching Theory for Logic Synthesis, Logic Synthesis and Verification, and Memory-Based Logic Synthesis, in 1993, 1996, 1999, 2001, and 2011, respectively.
He has served Program Chairman for the IEEE International Symposium on Multiple-Valued Logic (ISMVL) many times. Also, he was the Symposium Chairman of the 28th ISMVL held in Fukuoka,Japan, in 1998.
He received the NIWA Memorial Award in 1979, Takeda Techno-Entrepreneurship Award in 2001, and Distinctive Contribution Awards from IEEE Computer Society MVL-TC for papers presented at ISMVLs in 1986, 1996, 2003, 2004, and 2013. He has served as an associate editor of the IEEE Transactions on Computers. He is a Fellow of the IEEE.