1. Key Lab of Earth Exploration & Information Techniques of Ministry Education, Chengdu University of Technology, Chengdu 610059, China
2. School of Computer Science, Chengdu University, Chengdu 610106, China
3. School of Information and Engineering, Sichuan Tourism University, Chengdu 610100, China
4. Publicity and Information Center, Sichuan Provincial Department of Culture and Tourism, Chengdu 611930, China
5. College of Electronic Information and Automation, Civil Aviation University of China, Tianjin 300300, China