Institution: | (1) NTT Basic Research Laboratories, 3-1, Morinosato Wakamiya, Atsugi-shi, Kanagawa 243-01, Japan (E-mail: nisikawa@wave.brl.ntt.co.jp), JP;(2) NTT Integrated Information & Energy Systems Laboratories, 3-9-11, Midori-cho, Musashino-shi, Tokyo 180, Japan, JP |