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Studying CO2 storage with ambient-noise seismic interferometry: A combined numerical feasibility study and field-data example for Ketzin, Germany

Boullenger, B. (author), Verdel, A. (author), Paap, B. (author), Thorbecke, J.W. (author), Draganov, D.S. (author)

Seismic interferometry applied to ambient-noise measurements allows the retrieval of the seismic response between pairs of receivers. We studied ambient-noise seismic interferometry (ANSI) to retrieve time-lapse reflection responses from a reservoir during CO2 geologic sequestration, using the case of the experimental site of Ketzin, Germany. We...

journal article 2015

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Modeling estuarine morphodynamics under combined river and tidal forcing

Guo, L.C. (author)

Estuarine morphodynamics are of broad importance to estuaries’ functions related to navigation, human settlement and ecosystems. Inspired by the Yangtze River estuary (YRE), this study aims to explore the impact of river discharge, tides and their interaction on long-term estuarine morphodynamics. Use is made of 1D and 2D process-based models....

doctoral thesis 2014

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The electromagnetic response in a layered vertical transverse isotropic medium: A new look at an old problem

Hunziker, J.W. (author), Thorbecke, J.W. (author), Slob, E.C. (author)

We determined that the electromagnetic vertical transverse isotropic response in a layered earth can be obtained by solving two equivalent scalar equations, which were for the vertical electric field and for the vertical magnetic field, involving only a scalar global reflection coefficient. Besides the complete derivation of the full...

journal article 2014

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Passenger Transfer Chain Analysis for Reallocation of Heritage Space at Amsterdam Central Station

Starmans, M. (author), Verhoeff, L. (author), Van den Heuvel, J.P.A. (author)

Amsterdam Central Station is the second busiest station in The Netherlands. Several bottlenecks in the 125 years old monumental station exist due to present train and pedestrian volumes. Further traffic growth is expected. To understand and quantify the options for redesign, a thorough understanding of the interaction between the core traffic...

journal article 2014

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An approximate 3D computational method for real-time computation of induction logging responses

Bensdorp, S. (author), Petersen, S.A. (author), Van den Berg, P.M. (author), Fokkema, J.T. (author)

Over many years, induction logging systems have been used to create well formation logs. The major drawback for the utilization of these tools is the long simulation time for a single forward computation. We proposed an efficient computational method based on a contrast-type of integral-equation formulation, in which we applied an approximation...

journal article 2014

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Validation of an electroseismic and seismoelectric modeling code, for layered earth models, by the explicit homogeneous space solutions

Grobbe, N. (author), Slob, E.C. (author)

We have developed an analytically based, energy fluxnormalized numerical modeling code (ESSEMOD), capable of modeling the wave propagation of all existing ElectroSeismic and SeismoElectric source-receiver combinations in horizontally layered configurations. We compare the results of several of these modeled source-receiver combinations in a...

journal article 2013

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Tyre - Road Noise, Surface Characteristics and Material Properties

Li, M. (author)

Noise levels due to road traffic have reached intolerable high levels in and around many urban areas all around the world. Because of health reasons and reasons of well- being these noise levels have to be reduced. The noise produced from the interaction between the rolling tyre and road surface is one of the most important contributions in the...

doctoral thesis 2013

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Morphological modelling of strongly curved islands

Roelvink, D. (author), Den Heijer, C. (author), Van Thiel De Vries, J.S.M. (author)

Land reclamations and island coasts often involve strongly curved shorelines, which are challenging to be properly modeled by numerical morphological models. Evaluation of the long term development of these types of coasts as well as their response to storm conditions requires proper representation of the governing physical processes. Not all...

conference paper 2013

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A compressive strength model for recycled aggregate systems

Koenders, E.A.B. (author), Pepe, M. (author), Caggiano, A. (author), Martinelli, E. (author), Toledo Filho, R.D. (author)

conference paper 2013

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Local time stepping with the discontinuous Galerkin method for wave propagation in 3D heterogeneous media

Minisini, S. (author), Zhebel, E. (author), Kononov, A. (author), Mulder, W.A. (author)

Modeling and imaging techniques for geophysics are extremely demanding in terms of computational resources. Seismic data attempt to resolve smaller scales and deeper targets in increasingly more complex geologic settings. Finite elements enable accurate simulation of time-dependent wave propagation in heterogeneous media. They are more costly...

journal article 2013

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A new optimization approach for source-encoding full-waveform inversion

Moghaddam, P.P. (author), Keers, H. (author), Herrmann, F.J. (author), Mulder, W.A. (author)

Waveform inversion is the method of choice for determining a highly heterogeneous subsurface structure. However, conventional waveform inversion requires that the wavefield for each source is computed separately. This makes it very expensive for realistic 3D seismic surveys. Source-encoding waveform inversion, in which the sources are modeled...

journal article 2013

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Observations and modeling of steep-beach grain-size variability

Reniers, A.J.H.M. (author), Gallagher, E.L. (author), MacMahan, J.H. (author), Brown, J.A. (author), Van Rooijen, A.A. (author), Van Thiel de Vries, J.S.M. (author), Van Prooijen, B.C. (author)

Novel observations of surface grain-size distributions are used in combination with intra-wave modeling to examine the processes responsible for the sorting of sediment grains on a relatively steep beach (slope?=?1:7.5). The field observations of the mean grain size collected with a digital camera system at consecutive low and high tides for a 2...

journal article 2013

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Immiscible foam for enhancing oil recovery

Simjoo, M. (author)

Growing worldwide oil demand increased the need of new and efficient oil recovery methods. Gas injection in oil reservoirs is deemed one of the most widely used methods to increase oil recovery. However, the full potential of gas injection is often not realized due to poor vertical and areal sweep efficiency of the gas. Foaming could be a...

doctoral thesis 2012

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Nongeometrically converted shear waves in marine streamer data

Drijkoningen, G.G. (author), El Allouche, N. (author), Thorbecke, J.W. (author), Bada, G. (author)

Under certain circumstances, marine streamer data contain nongeometrical shear body wave arrivals that can be used for imaging. These shear waves are generated via an evanescent compressional wave in the water and convert to propagating shear waves at the water bottom. They are called “nongeometrical” because the evanescent part in the water...

journal article 2012

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Learning from Collaborative Research in Water Management Practice

Raadgever, G.T. (author), Mostert, E. (author), Van de Giesen, N.C. (author)

In order to deal with complex water management problems, it is increasingly claimed that researchers should collaborate with authorities and other stakeholders. According to the literature, such collaboration can enhance cognitive learning about the issues at stake, but there is little empirical evidence for this. In this paper, we assess...

journal article 2012

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A review of ASR modeling approaches for finite element analysis of dams and bridges

Esposito, R. (author), Hendriks, M.A.N. (author)

In this paper the anisotropic behavior of ASR swelling is simulated through a 1D smeared crack model. The choice of the engineering properties is discussed, in particular for the evolution of the tensile strength and the Young’s modulus during the swelling. The last one is used as the main indicator for ASRrelated damage. The model is hampered...

conference paper 2012

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Micro-hydration, pore connectivity and durability of cementitious materials

Koenders, E.A.B. (author), Ukrainczyk, N. (author), Hansen, W. (author)

Latest developments in Hymostruc enable the possibility to evaluate the pore connectivity of an evolving microstructure while also considering the contribution of the ITZ and air voids and to examine the influence on frost durability. The numerical model is used to visualize this phenomenon and to show the contribution of both the pores and the...

conference paper 2012

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Intra-annual rainfall variability control on interannual variability of catchment water balance: A stochastic analysis

Zanardo, S. (author), Harman, C.J. (author), Troch, P.A. (author), Rao, P.S.C. (author), Sivapalan, M. (author)

We evaluate the extent to which within-year rainfall variability controls interannual variability of catchment water balance. To this end, we analytically derive the probability density function of the annual Budyko evaporation index, B (i.e., the ratio of annual actual evapotranspiration to annual precipitation), by accounting for the...

journal article 2012

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Finite-difference modeling experiments for seismic interferometry

Thorbecke, J.W. (author), Draganov, D. (author)

In passive seismic interferometry, new reflection data can be retrieved by crosscorrelating recorded noise data. The quality of the retrieved reflection data is, among others, dependent on the duration and number of passive sources present during the recording time, the source distribution, and the source strength. To investigate these relations...

journal article 2011

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Performance Enhancement of Abrasive Waterjet Cutting

Abrasive Waterjet (AWJ) Machining is a recent non-traditional machining process. This technology is widely used in industry for cutting difficult-to-machine-materials, milling slots, polishing hard materials etc. AWJ machining has many advantages, e.g. it can cut net-shape parts, no heat is generated during the cutting process, it is...

doctoral thesis 2008