1. Associcate Professor, Dept. of Civil Engineering, Hong Kong Univ. of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
2. Associate Professor, Dept. of Civil Engineering, Hohai Univ., 1 Xikang Road, Nanjing, China; formerly, Graduate Student, Hong Kong Univ. of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.