1. Department of Civil and Structural Engineering, The Hong Kong Polytechnic University, Hung Hom, Hong Kong SAR, China
2. State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing (LIESMARS), Wuhan University, 430079, China
3. Department of Land Surveying & Geo-Informatics, The Hong Kong Polytechnic University, Hung Hom, Hong Kong SAR, China