1. Federal University of Rio Grande do Sul, Institute of Informatics, UFRGS/PPGC, Porto Alegre, Rio Grande do Sul, Brazil
2. Federal University of Ceará, Graduate Program in Teleinformatics Engineering (PPGETI/UFC), Center of Technology, Campus of Pici, Fortaleza, Ceará, Brazil
3. VALORIZA-Polytechnic Institute of Portalegre, Portalegre, Portugal
4. Expert Systems and Applications Laboratory (ESALAB), Faculty of Science, University of Salamanca, Salamanca, Spain