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Snellen, M. (author), Siemes, K. (author), Simons, D.G. (author)
We present a method for accurately estimating the bathymetry from multi-beam echo-sounder (MBES) travel-time measurements in environments with large variations in the water column sound speeds (both temporally and spatially). In this type of environments the water column sound speeds at the time of the MBES transmission are often not known,...
conference paper 2009
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Hoes, O.A.C. (author), Meijer, L.J.J. (author), Sarfianto, D.R. (author), Van der Ent, R.J. (author)
Population growth, increasing energy demand and depleting fossil fuel resei-ves put a pressure on conventional methods of electricity generation. Hydropower is an alternative energy source that is known to have a large capacity potential. However, previous estimations of the potential capacity have been inconsistent and incomplete. In this study...
conference paper 2014
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Hoogendoorn, R.M. (author)
Studies in stratigraphy are often driven by the predicted climate change and possible gains for the oil and gas industry. Because, at present predictions of the development of future deltaic architecture are insufficient. This thesis addresses the problem of qualitative and quantitative understanding of sedimentary systems in two stages. In the...
doctoral thesis 2006
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Eleftherakis, D. (author)
The economic importance of the Dutch rivers is very high as they are heavily used for inland waterway transport between the Netherlands and their neighbouring countries. A minimum depth must be guaranteed to keep the rivers navigable but also to ensure that the ships can carry maximum cargo. An attractive system for obtaining information about...
doctoral thesis 2013
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Snellen, M. (author), Eleftherakis, S. (author), Amiri-Simkooei, A. (author), Koomans, R.L. (author), Simons, D.G. (author)
This contribution presents sediment classification results derived from different sources of data collected at the Dordtse Kil river, the Netherlands. The first source is a multi-beam echo-sounder (MBES). The second source is measurements taken with a gamma-ray scintillation detector, i.e., the Multi-Element Detection System for Underwater...
journal article 2013
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El Allouche, N. (author), Drijkoningen, G.G. (author), Van der Neut, J.R. (author)
A widespread use of converted waves for shallow marine applications is hampered by spatial aliasing and field efficiency. Their short wavelengths require dense spatial sampling which often needs to be achieved by receivers deployed on the seabed. We adopted a new methodology where the dense spatial sampling is achieved in the common-receiver...
journal article 2010
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Sukhodolov, A.N. (author), Schnauder, I. (author), Uijttewaal, W.S.J. (author)
Shallow lateral shear layers forming between flows with different velocities, though essential for mixing processes in natural streams, have been examined only in laboratory settings using smooth, fixed?bed channels. This paper reports the results of an experimental study of a shear layer in a straight reach of a natural river where the layer,...
journal article 2010
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Jonkman, S.N. (author), Voortman, H.G. (author), Klerk, W.J. (author), van Vuren, B.G. (author)
This article highlights recent developments in flood risk management in the Netherlands and presents approaches for reliability analysis and asset management for flood defences and hydraulic infrastructure. The functioning of this infrastructure is of great importance for the country as large parts of it are prone to flooding. Based on a...
journal article 2018
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Van Prooijen, B.C. (author), Uijttewaal, W.S.J. (author)
The development of large coherent structures in a shallow mixing layer is analyzed. The results are validated with experimental data obtained from particle tracking velocimetry. The mean flow field is modeled using the self-similarity of the velocity profiles. The characteristic features of the down-stream development of a shallow mixing layer...
journal article 2002
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Amiri-Simkooei, A. (author), Snellen, M. (author), Simons, D.G. (author)
A method has recently been developed that employs multi-beam echo-sounder backscatter data to both obtain the number of sediment classes and discriminate between them by applying the Bayes decision rule to multiple hypotheses [ Simons and Snellen, Appl. Acoust. 70, 1258–1268 (2009) ]. In deep water, the number of scatter pixels within the beam...
journal article 2009
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De Vries, M. (author)
One dimension models - basic eauations, analytical models, numberical models. One dimensional models -suspended load, roughness and resistance of river beds. Solving river problems - tools, flood mitigation, bank protection.
lecture notes 1993
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Talmon, A.M. (author)
A two dimensional depth-averaged model for the concentration field of suspended sediment in river bend flow is formulated. Transport of suspended sediment in horizontal and vertical directions is modelled. Convection by the main and secondary flow and turbulent diffusion are incorporated. The model is capable of computing the exchange of...
report 1989
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Sieben, A. (author)
The ability of describing and predicting hydraulic and morphological phenomena in mountain rivers is limited, partially due to the limits of deterministic approaches where stochastic effects in sediment supply and water inflow are extremely significant, and partially due to the very specific conditions that can be observed in mountain rivers,...
report 1994
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Sieben, J. (author)
Present knowledge on fluvial processes in mountain rivers should be expanded to enable the development of projects dealing with mountain rivers or mountain-river catchment areas. This study reviews research on hydraulic and morphological features of mountain rivers. A major characteristic of mountain rivers is the variability of the hydraulic...
report 1993
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Ribberink, J.S. (author)
In Chapter I a derivation of the equations and an extension of the mathematical model will be carried out. The sediment-mixture is separated in a number of fractions - each with a representative grain size - and the equations describing the sediment-movement are split up for every fraction separately. In order to get some insight in the new...
report 1980
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Yossef, M.F.M. (author)
Groynes are structures constructed at an angle to the flow in order to deflect the flowing water away from critical zones. They are made of stone, gravel, rock, earth, or piles, beginning at the riverbank with a root and ending at the regulation line with a head. They serve to maintain a desirable channel for the purpose of flood control,...
report 2002
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Yossef, M.F.M. (author)
Report on a physical scale model test in the Fluid Mechanics lab on the effect of groynes on the bed and sediment transport in rivers.
report 2003
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Mosselman, E. (author)
A numerical two-dimensional model for river morphology is extended with bank erosion. The model is formulated in curvilinear coordinates. This allows the use of a boundary-fitted computational grid, suited for rivers with a curved centre-line and a non-uni form width. Dealing with non-homogeneous bank erodibility is shown to require a non...
report 1991
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Sieben, A. (author)
In this report, some classical and new simplifications in mathematical and numerical models for river morphology are compared for conditions representing rivers in mountainous areas (high values of Froude numbers and relatively large values of sediment transport rates). Options for simplification are summarized based on time scale of hydrographs...
report 1996
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Van Kuik, C.A. (author), Van Mazijk, A. (author)
In the one-dimensional 'Rhine Alarm Model' differences between the actual travel time of a pollution cloud, originating from an instantaneous release of an accidental spill, and the travel time, based on the flow velocity is represented by a lag coefficient. In the model this lag coefficient is defined by the relative difference between these...
report 1994
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