1. Vanung University, Department of Environmental Engineering No.1 Van-Nung Rd., Chung-Li, Tao-Yuan 32045, Taiwan, Republic of China. Phone: 886-3-4515811, ext. 700; Fax: 886-3-4622232; E-mail: chow@vnu.edu.tw
2. Department of Environmental Engineering, Vanung University, Tao-Yuan 32045, Taiwan, Republic of China