1. College of Earth Science and Engineering Shandong Univ. of Science and Technology 579 Qianwangang Road, West Coast New Area Qingdao Shandong Province 266590 China
2. Dept. of Civil Engineering and Management Changshu Institute of Technology No.99 South Third Ring Road Changshu Jiangsu 215500 China
3. Beijing Key Laboratory of Urban Spatial Information Engineering 15 Yangfangdian Road Beijing Haidian District 100038 China