1. Professor, Dept. of Ocean Engineering, Univ. of Rhode Island, Narragansett, RI 02882-1197 (corresponding author).
2. Ph.D. Candidate, College of Engineering, Ocean Univ. of China, Qingdao 266100, China.
3. Professor, Shandong Provincial Key Laboratory of Ocean Engineering, Ocean Univ. of China, Qingdao 266100, China.