1. Graduate School of Engineering, Tohoku University , 468–1 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-0845, Miyagi, Japan
2. International Research Institute of Disaster Science, Tohoku University , 468–1 Aramaki Aza Aoba, Aoba-ku, Sendai, Miyagi 980-0845, Miyagi, Japan