[by] Kazuhisa Makino, Suguru Tamaki, Masaki YamamotoDept. of Mathematical Informatics, Graduate School of Information Science and Technology, the University of Tokyo2007.4<MA21-B434>
21st Century COE Program, Chuo University and Resaerch and Development Initiative, Chuo University21st Century COE Program, Chuo University "Research on security and reliability in electronic society"[2003]