1. Prof., Dept. of Civ. Engrg., Nat. Chiao Tung Univ., Hsin Chu 300, Taiwan.
2. Grad. Res. Asst., Dept. of Harbor and River Engrg., Nat. Taiwan Oc. Univ., Keelung 202, Taiwan.
3. Prof., Dept. of Civ. Envir. Engrg., Univ. of Houston, Houston, TX 77004.
4. Prof., Dept. of Harbor and River Engrg., Nat. Taiwan Oc. Univ., Keelung 202, Taiwan.
5. Prof., Dept. of Civ. Engrg., Nat. Taiwan Univ., Taipei 100, Taiwan.