1. MIS Laboratory, University of Picardie Jules Verne, 33 rue Saint Leu, Amiens 80039, France;
2. STA Laboratory, National School of Engineering of Sfax, BP 1173, Sfax 3038, Tunisia e-mail:
3. MIS Laboratory, University of Picardie Jules Verne, 33 rue Saint Leu, Amiens 80039, France e-mail: