Department of Electrical Engineering and Computers, University of Coimbra, 3030-290 Coimbra, Portugal
Luís Pires Neves
Institute for Systems and Computer Engineering of Coimbra (INESCC), Coimbra—Institute for Systems Engineering and Computers at Coimbra, 3030-790 Coimbra, Portugal
José Luís Sousa
Institute for Systems and Computer Engineering of Coimbra (INESCC), Coimbra—Institute for Systems Engineering and Computers at Coimbra, 3030-790 Coimbra, Portugal