1. College of Geography and Environment, Shandong Normal University, Jinan, China
2. Beidou Research Institute, Faculty Of Engineering, South China Normal University, FoShan, China
3. School of Geography, South China Normal University, Guangzhou, China
4. Key Laboratory of Natural Resources Monitoring in Tropical and Subtropical Area of South China, Ministry of Natural Resources, Guangzhou, China
5. Department of Land Surveying and Geo-Informatics, The Hong Kong Polytechnic University, Hong Kong, China
6. Institute of Surveying and Mapping, Department of Natural Resources of Guangdong Province, Guangzhou, China