1. Department of Electrical Engineering, Federal University of Campina Grande, Aprígio Veloso 882, Universitário, Campina Grande 58429-090, Brazil
2. Department of Electrical Engineering, Federal University of Sergipe, Marechal Rondon Avenue, Jardim Rosa Elze, Aracaju 49100-000, Brazil
3. School of Computing and Engineering, University of Huddersfield, Huddersfield HD1 3DH, UK