1. Department of Electrical and Computer Engineering, University of Patras, 26504 Rio, Greece
2. Regional
Centre for Advanced Technologies and Materials, Department of Physical
Chemistry, Faculty of Science, Palacky University in Olomouc, 17. listopadu
1192/12, 771 46 Olomouc, Czech Republic
3. Department of Electrical
Engineering Technological Educational Institute of Western Greece, Patras, Greece
4. School of Electrical and Computer Engineering, National Technical University of Athens, Athens, Greece