Associate Professor School of Urban and Environmental Engineering Ulsan National Institute of Science and technology Postal Address: Bldg. 110, #1001-7, School of Urban and Environmental Engineering UNIST-gil 50, Ulsan 44919, Republic of Korea. Office: Bldg. 110, #1001-7 Tel: +82 52 217-2820 Fax: +82 52 217-2849 E-mail: skang at unist dot ac dot kr