1. Associate Professor, Graduate School of Engineering, Hokkaido Univ., Sapporo, Hokkaido 060-8628, Japan; formerly, Researcher, National Research Institute for Earth Science and Disaster Prevention, Miki, Hyogo 673-0515 Japan (corresponding author).
2. Assistant Professor, Dept. of Civil and Applied Mechanics, McGill Univ., Montreal, QC, Canada H3A 2K6.
3. Manager, Nippon Steel Engineering Co. Ltd., Shinagawa, Tokyo 141-8604, Japan; formerly, Researcher, National Research Institute for Earth Science and Disaster Prevention, Miki, Hyogo 673-0515 Japan.
4. Director of Hyogo Earthquake Engineering Center (E-Defense), National Research Institute for Earth Science and Disaster Prevention, Miki, Hyogo 673-0515, Japan.