António Lopes
ESCE IPS - Polytechnic Institute of Setúbal, Setúbal,
Portugal

Henrique S. Mamede
2) Institute for Systems and Computer Engineering, Technology and Science (INESC TEC), Porto, Portugal. 3) Department of Science and Technology, Universidade Aberta, Lisbon,
Portugal

Leonilde Reis
ESCE IPS - Polytechnic Institute of Setúbal, Setúbal,
Portugal

Arnaldo Santos
2) Institute for Systems and Computer Engineering, Technology and Science (INESC TEC), Porto, Portugal. 3) Department of Science and Technology, Universidade Aberta, Lisbon,
Portugal