1. UFMA/Computer Science Department, Universidade Federal do Maranhão, Campus do Bacanga, São Luís 65085-580, Brazil
2. UTAD/Engineering Department, Universidade de Trás-os-Montes e Alto Douro, 5000-801 Vila Real, Portugal
3. INESC-TEC—Institute for Systems and Computer Engineering, Technology and Science, 4200-465 Porto, Portugal
4. CMADE—Centre of Materials and Building Technologies, UTAD, 5000-801 Vila Real, Portugal