1. Department of Innovation Science, Tokyo Institute of Technology, 3-3-6 Shibaura, Minato-ku, Tokyo 108-0023, Japan
2. Graduate School of Humanities and Social Sciences, Hiroshima University, 1-1-89 Higashisendamachi, Naka-ku, Hiroshima 730-0053, Japan
3. Department of Industrial Engineering and Economics, Tokyo Institute of Technology, W9-86, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8552, Japan