1. Assistant Professor, Dept. of Civil and Environmental Engineering, King Faisal Univ., Room 1049, Building 68, Alahsa, Saudi Arabia 31982 (corresponding author).
2. Research Associate, Institute of Industrial Science, Univ. of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan.
3. Assistant Professor, Dept. of Civil and Environmental Engineering, King Faisal Univ., Room 1049, Building 68, Alahsa 31982, Saudi Arabia.
4. Professor, Institute of Industrial Science, Univ. of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan.