1. College of Intelligent Equipment, Shandong University of Science and Technology, Tai’an, Shandong 271000, China
2. School of Engineering, Technology and Design, Canterbury Christ Church University, Canterbury CT1 1QU, UK
3. College of Continuing Education, Shandong University of Science and Technology, Tai’an, Shandong 271000, China
4. College of Computer Science and Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China