Affiliation: | 1. Energy Network Group, Energy Technology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), AIST Central 2, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan;2. Division of Electrical and Computer Engineering, Graduate School of Engineering, Yokohama National University, 79-5 Tokiwa-dai, Hodogaya-ku, Yokohama 240-8501, Japan;3. Department of Electrical Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan |