1. Ph.D. Candidate, Dept. of Architecture and Architectural Engineering, Seoul National Univ., Gwanak-ro 1, Gwanak-gu, Seoul 151-742, Korea.
2. Professor, Dept. of Architecture and Architectural Engineering, Seoul National Univ., Gwanak-ro 1, Gwanak-gu, Seoul 151-742, Korea.
3. Postdoctoral Researcher, Construction Engineering and Management Division, Charles Durham School of Architectural Engineering and Construction, Univ. of Nebraska–Lincoln, W116 Nebraska Hall, Lincoln, NE 68588 (corresponding author).