1. Department of Electrical and Electronic Engineering; Toyota National College of Technology; 2-1 Eisei-cho Toyota 471-8525 Aichi Japan
2. Department of Materials Science and Engineering; Yamaguchi University; 2-16-1 Tokiwadai Ube 755-8611 Yamaguchi Japan
3. Department of Electrical Engineering and Computer Science; Nagoya University; C3-1 Furo-cho Chikusa-ku Nagoya 464-8603 Japan