1. College of Resources and Environmental Science, Hunan Normal University, Changsha, China
2. Key Laboratory of Geospatial Big Data Mining and Application, Changsha, Hunan Province, China
3. School of Resource and Environment Sciences, Wuhan University, Wuhan, China
4. School of Geographic and Biologic Information, Nanjing University of Posts and Telecommunications, Nanjing, China
5. Smart Health Big Data Analysis and Location Services Engineering Lab of Jiangsu Province, Nanjing University of Posts and Telecommunications, Nanjing, China