1. PhD Candidate, Dept. of Environmental Engineering, Inha Univ., 253 Yonghyun-Dong, Nam-Ku, Inchon 402-751, Korea.
2. Associate Professor, Dept. of Environmental Engineering, Inha Univ., 253 Yonghyun-Dong, Nam-Ku, Inchon 402-751, Korea.
3. COE Research Fellow, Division of Urban Environmental Systems, Research Center for Advanced Science and Technology, Univ. of Tokyo, 4-6-1, Komaba, Meguro-ku, Tokyo 153, Japan.
4. Professor, Dept. of Environmental Engineering, Inha Univ., 253 Yonghyun-Dong, Nam-Ku, Inchon 402-751, Korea.