Institution: | 1. Mathematics Laboratories, College of Arts and Sciences, Showa University, Fuji-Yoshida, Yamanashi 403-005, Japan;2. Department of Applied Mathematics, Faculty of Engineering, Yokohama National University, Hodogaya, Yokohama 240-8501, Japan;3. Oyama National College of Technology, Oyama, Tochigi 323-0806, Japan;4. Graduate School of Information Sciences, Tohoku University, Aoba, Sendai 980-8579, Japan |