1. College of Geomatics and Geoinformation, Guangxi Key Laboratory of Spatial Information and Geomatics, the College of Mechanical and Control Engineering, and the College of Earth Sciences, Guilin University of Technology, Guilin, China
2. College of Geomatics and Geoinformation, Guilin University of Technology, Guilin, China
3. Department of Electrical, Biomedical, and Computer Engineering, University of Pavia, Pavia, Italy