Affiliation: | 1. UFRGS - Department of Electrical Engineering , Av. Osvaldo Aranha 103 , 90035-190 Porto Alegre-RS, Brazil ;3. UFRGS - Department of Electrical Engineering , Av. Osvaldo Aranha 103 , 90035-190 Porto Alegre-RS, Brazil;4. LAAS-CNRS , University of Toulouse , 7 Avenue du Colonel Roche, 31077, Toulouse cedex 4, France |