1. JST/CREST Research Fellow, Hydrologic Engineering Research Team, Hydraulic Engineering Research Group, Public Works Research Institute, Minamihara 1-6, Tsukuba, Ibaraki, Japan 305-8516.
2. Leader, Hydrologic Engineering Research Team, Hydraulic Engineering Research Group, Public Works Research Institute.
3. Director, Hydrology Division, Royal Irrigation Department, Kingdom of Thailand.