1. Beijing Key Laboratory of Transportation Data Analysis and Mining, School of Computer and Information Technology, Beijing Jiaotong University, Beijing, China
2. Department of Electrical and Electronic Engineering, The University of Melbourne, Parkville, VIC, Australia
3. State Key Laboratory of Rail Traffic Control and Safety, Beijing Jiaotong University, Beijing, China
4. National Key Laboratory of Science and Technology on Communications, University of Electronic Science and Technology of China, Chengdu, China
5. Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Canada