1. Graduate Student, Dept. of Architecture, Seoul National Univ., San 56-1, Shinlim-Dong, Kwanak-Gu, Seoul 151-744, South Korea.
2. Professor, Dept. of Architecture, Seoul National Univ., San 56-1, Shinlim-Dong, Kwanak-Gu, Seoul 151-744, South Korea (corresponding author).