1. Dept. of Industrial Design, Takushoku University. 815-1, Tate-machi, Hachioji, Tokyo 193, Japan.
2. Mesoscopic Materials Research Center, Kyoto University. Yoshida-honmachi, Sakyo-ku, Kyoto-shi 606-01, Japan.
3. National Institute of Materials and Chemical Research, AIST. 1-1-4, Higashi, Tsukuba 305, Japan.