1. Polytechnic School of Pernambuco, University of Pernambuco (UPE), Recife, Brazil & Federal Institute of Pernambuco (IFPE), Palmares, Brazil
2. Departamento de Computación, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
3. Polytechnic School of Pernambuco, University of Pernambuco (UPE), Recife, Brazil