Xi Chen¹, Xinyi Shen², Kang He³, Zengchao Hao⁴, Yaokui Cui⁵ and Yang Hong¹, (1)Peking University, Institute of Remote Sensing and GIS, School of Earth and Space Sciences, Beijing, China, (2)University of Connecticut, Civil and Environmental Engineering, Storrs, CT, United States, (3)University of Connecticut, College of Civil and Environmental Engineering, Storrs, United States, (4)Beijing Normal University, Beijing, China, (5)Institute of RS and GIS, Penking University, Beijing, China