1. School of Mathematical Sciences Nanjing Normal University Nanjing China
2. Key Laboratory of VGE of Ministry of Education Nanjing Normal University Nanjing China
3. Key Laboratory of National Geographic Census and Monitoring Ministry of Natural Resources WuHan China
4. Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing China
5. Department of Civil Engineering University of Bristol Bristol UK
6. Shenzhen Research Institute of Nankai University Shenzhen China