1. Research Professor, Dept. of Computational Science and Engineering, Yonsei Univ., Seoul 03722, Korea.
2. Associate Professor, Dept. of Computational Science and Engineering, Yonsei Univ., Seoul 03722, Korea (corresponding author).
3. Professor, Dept. of Civil and Environmental Engineering, Yonsei Univ., Seoul 03722, Korea.
4. Associate Professor, Dept. of Civil, Structural and Environmental Engineering, State Univ. of New York at Buffalo, 233 Jarvis Hall, Buffalo, NY 14260.