1. Assistant Professor, LABEST, Faculty of Engineering, Univ. of Porto, 4200-465 Porto, Portugal (corresponding author).
2. Research Scholar, Faculty of Engineering, Univ. of Porto, 4200-465 Porto, Portugal.
3. Associate Professor, Faculty of Engineering, Univ. of Porto, 4200-465 Porto, Portugal.
4. Associate Professor, LABEST, Faculty of Engineering, Univ. of Porto, 4200-465 Porto, Portugal.