1. Department of Social Informatics, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501, Japan
2. Department of Computational Science, Telkom University, Jl. Telekomunikasi No. 1, Bandung 40257, Indonesia
3. Unit of Design, Kyoto University, 91 Chudoji, Awata-cho, Shimogyo-ku, Kyoto 600-8813, Japan