1. Department of Fundamental Courses, Shandong University of Science and Technology, Tai’an 271000, Shandong, China
2. College of Electronic and Information Engineering, Shandong University of Science and Technology, Qingdao 266590, Shandong, China
3. College of Intelligent Equipment, Shandong University of Science and Technology, Tai’an 271000, Shandong, China