Remote sensing data as a soil moisture indicator for grass-covered dikes

Dikes hold back water and protect the land behind it from flooding. Due to rising sea levels, land subsidence and more extreme weather patterns, the function of dikes become increasingly important. To ensure dike safety, dikes are regularly inspected. With about 22,500 kilometers of dikes in the Netherlands, this is a very slow, costly and time...

Discontinuous Galerkin Methods for Numerical Weather Prediction: DG in a large-eddy simulation

The coarse grid of numerical weather prediction and climate models requires parametrization models to resolve atmospheric processes that are smaller than the grid size. For parametrization development, these processes are simulated by a high resolution model. At the Royal Netherlands Meteorological<br/>Institute, the Dutch Atmospheric Large-Eddy...

Optimizing the flow of vessels through locks by improving the operational management of locks

Nowadays, the capacity of the lock becomes more important, since ports become busier and waterways more crowded. Still, the management of locks has not changed very much. Especially since locks are one of the most important factors that determine the capacity of a waterway. A lock limits the capacity of a waterway in two ways. First of all, the...

Regularisatie Methodes voor Seismische Tomografie (Regularization Methods for Seismic Tomography)

In seismic tomography, parts of the Earth are reconstructed by the travel times of seismic waves that are measured by seismometers. These tomographic problems can be formulated as a system of linear equations. Unfortunately, most of the time the system is ill-posed, because of ray bending and noise. This problem can not only be found in...

Criteria voor toepassing van bekledingen op waterkeringen: Hulpmiddel voor ontwikkeling van innovatieve dijkbekledingen

Traditioneel worden dijken bekleedt met steenzettingen, asfalt, gras of breuksteen. Echter, er worden steeds meer initiatieven voorgesteld waarbij innovatieve materialen worden toegepast als dijkbekleding. Deze initiatieven zul len in de toekomst leiden tot een efficienter of maatschappelijk beter geaccepteerde dijkbekleding. Tot nag toe is voor...

Video-based monitoring of the Egmond beach- and shoreface nourishments: Evaluation of the 1999 nourishments with the help of the Argus video system

Video-based monitoring of the Egmond beach- and shoreface nourishments: Evaluation of the 1999 nourishments with the help of the Argus video system

The Dutch coast at Egmond is a highly dynamic region where nourishments of sand are necessary to compensate erosion. In comparison with neigbouring coastal areas the necessary nourishment frequency is relatively high. The latest intervention concerns a combined beach- and shoreface nourishment in the spring and summer of 1999. In order to...

Three dimensional experimental investigation of a hypersonic double-ramp flow

The flow over a 15?-45? double compression ramp was studied at Mach 7.5. CFD computations are compared to 2 component PIV (particle image velocimetry) measurements. Furthermore stereoscopic PIV was used to measure the three component velocity vector, enabling to perform a 3D flow survey. The overall flow topology is assessed and special...