1. Sun Yat-sen University,School of Geography and Planning,Guangzhou,P.R.China,510275
2. China University of Geosciences,School of Computer Science,Wuhan,P.R.China,430078
3. Nanchang Institute of Technology,Jiangxi Province Key Laboratory of Water Information Cooperative Sensing and Intelligent Processing,Nanchang,P.R.China,330099