1. Department of Electrical Engineering and Information Technology, University of Naples Federico II, Naples, Italy
2. Modelling Engineering Risk and Complexity, Scuola Superiore Meridionale, Naples, Italy
3. Department of Mathematics and Applications “R. Caccioppoli,”, University of Naples Federico II, Naples, Italy
4. Department of Information Engineering, Electrical Engineering and Applied Mathematics, University of Salerno, Salerno, Italy