1. Guizhou Provincial Key Laboratory of Public Big Data, Guizhou University, Guiyang, Guizhou 550025, China
2. College of Computer Science & Technology, Guiyang, Guizhou 550025, China
3. School of Computer Science, China University of Geoscience, Wuhan 430074, China
4. Hubei Key Laboratory of Intelligent Geo-Information Processing, China University of Geosciences, Wuhan 430074, China
5. School of Computing Science, University of East Anglia, Norwich NR4 7TJ, UK