1. College of Mathematics and Systems Science, Shandong University of Science and Technology, Qingdao 266590, China
2. Institute of Complexity Science, Qingdao University, Qingdao 266071, China
3. Department of Electrical Engineering, Lakehead University, Thunder Bay, ON, Canada P7B 5E1
4. College of Information and Electrical Engineering, Shandong Jianzhu University, Jinan 250101, China