1. Assistant Professor, Dept. of Architectural Engineering, Dankook Univ., 448-701, Republic of Korea.
2. Senior Researcher, Building Structures and Materials Research Dept., Steel Structure Research Division, Research Institute of Industrial Science and Technology, 180-1 Songdo-Dong, Incheon 406-840, Republic of Korea (corresponding author).
3. Assistant Professor, Dept. of Architecture, Ajou Univ., San 5, Woncheon-dong, Suwon 443-749, Republic of Korea.
4. Graduate Student, Dept. of Architecture, Ajou Univ., San 5, Woncheon-dong, Suwon 443-749, Republic of Korea.