1. Associate Professor, Dept. of Ocean Engineering, Pukyong National Univ., 599-1 Daeyeon 3 Dong, Namgu, Busan, 608-737, South Korea (corresponding author).
2. Dept. of Civil and Environmental Engineering, Univ. of Connecticut, 261 Glenbrook Road, Storrs, CT 06269-2237.
3. Graduate Student, Dept. of Ocean Engineering, Pukyong National Univ., 599-1 Daeyeon 3 Dong, Namgu, Busan, 608-737, South Korea.
4. Professor, Dept. of Civil, Construction, and Environmental Engineering, North Carolina State Univ., Mann Hall, Stinson Drive, Raleigh, NC 27695-7908.