国家自然科学基金41574003,41774004;国家测绘地理信息局科技创新项目2018KJ0205;国家科技基础性工作专项2015FY210400The National Natural Science Foundation of China.41574003,41774004;The Scientific and Technological Innovation Project of Surveying, Mapping and Geo-information2018KJ0205;The National Basic Work of Science and Technology of China2015FY210400