1. Ningbo University, College of Architectural Engineering, Civil Engineering and Environment, 818 Fenghua Road, Ningbo, Zhejiang 315211, China
2. Tongji University, College of Surveying and Geo-informatics, 1239 Siping Road, Shanghai 200092, ChinacKey Laboratory of Advanced Engineering Survey of NASMG, 1239 Siping Road, Shanghai 200092, China
3. University of Maryland College Park, Applied Mathematics & Statistics, and Scientific Computation, Maryland 20742
4. Tongji University, College of Surveying and Geo-informatics, 1239 Siping Road, Shanghai 200092, China