Affiliation: | (1) Media and Information Technology Center, Yamaguchi University, Yoshida 1677-1, Yamaguchi 753-8511, Japan;(2) Graduate School of Science and Engineering, Yamaguchi University, Tokiwadai 2-16-1, Ube 755-8611, Japan;(3) Department of Electronics and Computer Science, Tokyo University of Science, Daigaku-dori 1-1-1, Sanyo-Onoda Yamaguchi, 756-0884, Japan;(4) Yamaguchi Study Center, The Open University of Japan, Daigaku-dori 1-1-1, Sanyo-Onoda 756-0884, Japan |