1. Professor, Dept. of Civil Engineering, National Chi Nan Univ., 1 University Rd., PuLi, Nantou 545, Taiwan.
2. Assistant Professor, Dept. of Bioenvironmental Engineering, Chung Yuan Christian Univ., 22 Pu-Jen, Pu-chung Li, Chung-Li, 32023, Taiwan.
3. Associate Professor, Dept. of Environmental Engineering and Management, Chaoyang Univ. of Technology, Wufeng, Taichung, 413, Taiwan.
4. Master, Dept. of Civil Engineering, National Chi Nan Univ., 1 University Rd., PuLi, Nantou 545, Taiwan.