1. School of Resource and Environmental Sciences, Wuhan University, Wuhan 430079, China
2. Department of Geography, University of Zurich, 8057 Zurich, Switzerland
3. Texas A&M Transportation Institute, 1111 RELLIS Pkwy, Bryan, TX 77807, USA
4. Key Laboratory of Geographic Information Systems, Ministry of Education, Wuhan University, Wuhan 430079, China
5. Collaborative Innovation Center of Geospatial Technology, Wuhan University, Wuhan 430079, China
6. School of Remote Sensing and Information Engineering, Wuhan University, Wuhan 430079, China