1. Department of Geography and Centre for Geo-computation Studies; Hong Kong Baptist University; Kowloon Hong Kong
2. State Key Laboratory for Information Engineering in Surveying, Mapping and Remote Sensing; Wuhan University; Wuhan China
3. GIS Centre; Lund University; Lund Sweden
4. School of Resource and Environment Science; Wuhan University; Wuhan China
5. Key Laboratory of Geographic Information System, Ministry of Education; Wuhan University; Wuhan China