1. Department of Electrical and Computer Engineering, University of Western Macedonia, Kozani, Greece
2. Department of Networks and Digital Media, Kingston University, Kingston upon Thames, U.K.
3. Department of Computer Science, International Hellenic University, Thessaloniki, Greece
4. Sidroco Holdings Ltd, Nicosia, Cyprus
5. Physics Department, Aritostle, University of Thessaloniki, Thessaloniki, Greece
6. Shenzhen Institute for Advanced Study, University of Electronic Science and Technology of China, Shenzhen, China