1. Director, Research Center for Ocean Energy and Strategies, National Taiwan Ocean Univ., Keelung 202, Taiwan; and Professor, Dept. of Hydraulic and Ocean Engineering, National Cheng Kung Univ., Tainan 701, Taiwan.
2. Assistant Professor, Dept. of Civil Engineering, National Chung Hsing Univ., No. 250, Kuokuang Rd., Taichung 402, Taiwan. (corresponding author).
3. Deputy Chief Engineer, Public Works Bureau, Kaohsiung City Government, Kaohsiung 802, Taiwan.