1. College of Geodesy and Geomatics, Shandong University of Science and Technology, Qingdao, China
2. Key Laboratory of Marine Environmental Survey Technology and Application, Ministry of Natural Resources, Guangzhou, China
3. South China Sea Sea Area and Island Center, Ministry of Natural Resources, Guangzhou, China
4. Qingdao YueHai Information Service Company Ltd., Qingdao, China