1. Graduate School of Information Science and Technology, Hokkaido University, Sapporo, Japan
2. Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan
3. Chubu Electric Power Company, Inc., Nagoya, Japan
4. Department of Electrical Engineering and Bioscience, Waseda University, Tokyo, Japan
5. Research Center of Nuclear Physics, Osaka University, Osaka, Japan