1. Department of Economics, Management, Industrial Engineering and Tourism (DEGEIT), Campus Universitário de Santiago, University of Aveiro, 3810-193 Aveiro, Portugal
2. Department of Mathematics (DMat) and Center for Research and Development in Mathematics and Applications (CIDMA), Campus Universitário de Santiago, University of Aveiro, 3810-193 Aveiro, Portugal
3. Department of Mechanical Engineering (DEM), Campus Universitário de Santiago, University of Aveiro, 3810-193 Aveiro, Portugal