He has held faculty/research positions at Osaka University, Japan; IBM T. J. Watson Research Center, Yorktown Height, NY; the Naval Postgraduate School, Monterey, CA; and Kyushu Institute of Technology, Iizuka, Japan. Now, he is a Professor of 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 and 2004. He has served an associate editor of the IEEE Transactions on Computers. He is a Fellow of the IEEE.