1. a Kyoto Municipal Institute of Industrial Research, Chudoji, Shimogyo-ku, Kyoto 600-8813, Japan
2. b Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606, Japan
3. c Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606, Japan
4. d Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606, Japan
5. e Shonan Institute of Technology, Tsujido-nishikaigan, Fujisawa, Kanagawa 251, Japan