1. Post-Doctoral Researcher, Fond National de la Recherche Scientifique; and Dept. of Civil Engineering, Hydraulics Unit, Univ. catholique de Louvain, Place du Levant, 1, B-1348 Louvain-la-Neuve, Belgium.
2. Graduate student, Dept. of Civil Engineering, Hydraulics Unit, Univ. catholique de Louvain, Place du Levant, 1, B-1348 Louvain-la-Neuve, Belgium.
3. Professor, Dept. of Civil Engineering, Hydraulics Unit, Univ. catholique de Louvain, Place du Levant, 1, B-1348 Louvain-la-Neuve, Belgium.