1. Faculty of Integrated Human Studies, Kyoto University, Kyoto 606-8501, Japan
2. School of Political Science and Economics, Meiji University, 1-1 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8301, Japan
3. Factory Automation System Department, Takagi-Shokai Co., 2-2-7 Kitasennzoku, Ohta-ku, Tokyo 145-0062, Japan
4. Sony Computer Science Laboratories, 3-14-13 Higashi-Gotanda, Shinagawa-ku, Tokyo 141-0022, Japan
5. Department of Complex Systems, Future University – Hakodate, 116-2 Kameda-Nakano-cho, Hakodate, Hokkaido 041-8655, Japan