1. Graduate School of Science and Technology, Chiba University, Chiba, Japan. wangwei@graduate.chiba-u.jp
2. Graduate School of Science and Technology, Chiba University, Chiba, Japan
3. Dept. of Electronics and Mechanical Engineering, Chiba University, Chiba, Japan. nonami@faculty.chiba-u.jp
4. Dept. of Electrical and Electronic Engineering, Utsunomiya University, Chiba, Japan. hirata@cc.utsunomiya-u.ac.jp
5. S.B.D. Planning Department, Epson Corporation, Suwa-gun, Japan. Miyazawa.Osamu@exc.epson.co.jp