1. School of Civil Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
2. School of Civil Engineering, National Technical University of Athens, 15773 Athens, Greece
3. Scientia Maris, Chalandri, 15234 Athens, Greece
4. MarineTraffic, 11525 Athens, Greece
5. School of Engineering, University of the Aegean, 84100 Ermoupolis, Greece
6. Department of Geography, Ghent University, 9000 Ghent, Belgium