1. Department of Telecommunication Systems and Networks, TEI of Messolonghi, 30300 Nafpaktos, Greece
2. CISM, Kingston University London, Penrhyn Road, Surrey KT12EE, UK
3. Micro2Gen Ltd., New Technology Park NCSR Demokritos, Agia Paraskevi, 15341 Athens, Greece
4. Medical Informatics Laboratory, Democritus University of Thrace, 68100 Alexandroupolis, Greece