1. School of Computer Science and Technology, Shandong University of Technology, Zibo, China
2. School of Computer Science and Technology, Shandong University of Technology, China and School of Software, Dalian University of Technology, Dalian, Kaifaqu, China
3. School of Computer Science and Technology, Shandong University of Technology, China and School of Computing and Mathematics, Manchester Metropolitan University, Metropolitan, Manchester, UK
4. Department of Computer Science and Information Engineering, Asia University, Taichung, Taiwan
5. Zhejiang University, Zhejiang, Hangzhou, China
6. Department of Computer Science, Mobile Systems Laboratory (MoSys Lab), University of Nicosia and University of Nicosia Research Foundation, Nicosia, Cyprus
7. Department of Management Science and Technology, Hellenic Mediterranean University, Crete, Greece
8. Department of Electrical and Computer Engineering, Hellenic Mediterranean University, Heraklion, Greece