1. School of Geography and Ocean Science, Nanjing University, Nanjing, China
2. Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology, Nanjing University, Nanjing, China
3. National Security College of National Defense University, Beijing, China
4. Collaborative Innovation Center for the South Sea Studies, Nanjing University, Nanjing, China
5. Collaborative Innovation Center of Novel Software Technology and Industrialization, Nanjing University, Nanjing, China
6. Kunming University of Science and Technology, Kunming, China