1. Associate Professor, Dept. of Civil and Environmental Engineering, Yamaguchi Univ., Ube, Yamaguchi, Japan.
2. Assistant Professor, Dept. of Civil Engineering, North Dakota State Univ., Fargo, ND 58108 (corresponding author).
3. CEO, Inai Conex, Co., Ltd., Minato, Osaka, Japan.
4. Professor Emeritus, Dept. of Civil and Environmental Engineering, Yamaguchi Univ., Ube, Yamaguchi, Japan.