1. State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing (LIESMARS), Wuhan University, Wuhan, China
2. Department of Geography, University of the Punjab, Lahore, Punjab, Pakistan
3. Faculty of Engineering, Al-Azhar University, Cairo, Egypt
4. National Engineering Research Center for Geographic Information System (NERCGIS), School of Geography, China University of Geosciences, Wuhan, China
5. Key Laboratory of Digital Earth Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China