1. Department of Electrical Engineering, Tokyo University of Science, Tokyo, Japan
2. Graduate School of Informatics and Engineering, The University of Electro-Communications, Tokyo, Japan
3. Department of Information Systems Engineering, University of Kitakyushu, Fukuoka, Japan
4. Artificial Intelligence eXploration Research Center (AIX), The University of Electro-Communications, Tokyo, Japan
5. Innovation Design Initiative, National Institute of Information and Communications Technology, Tokyo, Japan
6. Social-ICT System Laboratory, National Institute of Information and Communications Technology, Tokyo, Japan