1. Department of Electronic and Communication Engineering and the Hebei Key Laboratory of Power Internet of Things Technology, North China Electric Power University, Baoding, Hebei, China
2. Department of Electronic and Communication Engineering, North China Electric Power University, Baoding, Hebei, China
3. Department of Computer Science and Software Engineering, Monmouth University, West Long Branch, NJ, USA
4. Computer and Communication Engineering College, Liaoning Petrochemical University, Fushun, China