1. Faculty of Information Technology, Beijing University of Technology, Beijing 100124, China
2. Beijing Key Laboratory on Integration and Analysis of Large-Scale Stream Data, Beijing, China
3. National Engineering Laboratory for Critical Technologies of Information Security Classified Protection, Beijing 100124, China
4. School of Computer Science, Beijing Information Science and Technology University, Beijing 100101, China
5. College of Applied Science, Beijing University of Technology, Beijing 100124, China