1. Associated Laboratory for Energy, Transports and Aeronautics (LAETA-PROA), Faculty of Engineering, University of Porto (FEUP), Rua Dr. Roberto Frias, s/n, 4200-465 Porto, Portugal
2. Centro de Recursos Naturais e Ambiente (CERENA-Porto), School of Engineering of the Polytechnic of Porto, Rua Dr. António Bernardino de Almeida, 431, 4200-072 Porto, Portugal