1. Senior Researcher, Nakdong River Environment Research Center, 24, Pyeongni 1-gil, Pyeongni-ri, Dasan-myeon, Goryeong-gun 717-873, Gyeongsangbuk-do, Republic of Korea.
2. Professor, Dept. of Civil Engineering, Changwon National Univ., 9 Sarim, Changwon 641-773, Gyeongnam, Republic of Korea (corresponding author). E-mail: siwan@changwon.ac.kr