He acquired MS in mathematics and PhD in information technology at University of Tokyo. He worked for Corporate Research Laboratory of Fuji Xerox Inc., and started his research on cryptography there. When he worked for University of Tokyo after quitting Fuji Xerox Inc., he has become interested in the machine learning theory and is currently active in this field. After working for Carnegie Mellon University CyLab Japan for a few years, he started to work for University of Hyogo at the current position.

• ・The theory of kernel multivariate analysis, in particular, the design theory of kernel functions for discrete data structure.
• ・The theory of feature selection and dimension reduction based on information theory and statistics.
• ・The theory of public key cryptography, in particular, the untraceable authentication protocol.