1. Research Fellow, International Institute for Urban Systems Engineering, Southeast Univ., Nanjing 210096, China; Lecturer, Dept. of Civil Engineering, Faculty of Engineering, Assiut Univ., Assiut 71516, Egypt.
2. Professor, Dept. of Urban and Civil Engineering, Ibaraki Univ., 4-12-1 Nakanarusawa-cho, Hitachi 316-8511, Japan (corresponding author).