[1]School of Earth Sciences and Engineering, Hohai University, Nanjing 210098, China;
[2]School of Earth Sciences and Resources, China University of Geosciences (Beijing), Beijing 100083, China;
[1]School of Earth Sciences and Engineering, Hohai University, Nanjing 210098, China;
[3]Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, China;
[4]Key Laboratory of Virtual Geographic Environment (Ministry of Education), Nanjing Normal University, Nanjing 210023, China;
[5]Department of Electrical Engineering, University of Texas at Dallas, Richardson, TX 75080-3021, USA;
[5]Department of Electrical Engineering, University of Texas at Dallas, Richardson, TX 75080-3021, USA;