1. Faculty of Geomatics, Lanzhou Jiaotong University, Lanzhou, People’s Republic of China
2. National-Local Joint Engineering Research Center of Technologies and Applications for National Geographic State Monitoring, Lanzhou, People’s Republic of China
3. Gansu Provincial Key Laboratory of Science and Technology in Surveying & Mapping, Lanzhou, Gansu, People’s Republic of China
4. Key Laboratory of Cryospheric Science and Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, People’s Republic of China
5. Department of Geoinformatics and Surveying, Faculty of Geosciences and Environment Engineering, Southwest Jiaotong University, Chengdu, People’s Republic of China