1. Technology Research Center, Samsung C&T Corporation, Seoul 137-857, Republic of Korea
2. Department of Architectural Engineering, Kyung Hee University, Yongin 446-701, Republic of Korea
3. Building Technologies Department, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
4. Department of Architectural Engineering, Sungkyunkwan University, Suwon 440-746, Republic of Korea