1. Res., Hydromechanics Sect., Fac. of Civ. Engrg., Delft Univ. of Technol., P.O. Box 5048, 2600 GA Delft, The Netherlands; formerly, PhD Res., Delft Hydraulics, P.O. Box 177, 2600 MH Delft, The Netherlands.
2. Sr. Sci., Delft Hydraulics, P.O. Box 177, 2600 MH Delft, The Netherlands; and Prof., Delft Univ. of Technol., Fac. of Civ. Engrg., P.O. Box 5046, 2600 GA Delft, The Netherlands.
3. PhD student, Dept. of Civ. and Envir. Engrg., Università degli Studi di Trento, Via Mesiano 77, 38050 Trento, Italy.