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Physics-based Pre-conditioners for Large-scale Subsurface Flow Simulation

Diaz Cortes, G.B. (author), Vuik, Cornelis (author), Jansen, J.D. (author)

We consider deflation-based pre-conditioning of the pressure equation for large-scale reservoir models with strong spatial variations in the permeabilities. The use of deflation techniques involves the search for good deflation vectors, which usually are problem-dependent. We propose the use of proper orthogonal decomposition (POD) to generate...

conference paper 2016

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Multiscale Gradient Computation for Subsurface Flow Models

Jesus de Moraes, R. (author), Rodrigues, J.R.P. (author), Hajibeygi, H. (author), Jansen, J.D. (author)

We present an efficient multiscale (MS) gradient computation that is suitable for reservoir management studies involving optimization techniques for, e.g., computer-assisted history matching or life-cycle production optimization. The general, algebraic framework allows for the calculation of gradients using both the Direct and Adjoint derivative...

conference paper 2016

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Clustering Techniques for Value-of-information Assessment in Closed-loop Reservoir Management

Goncalves Dias De Barros, E. (author), Yap, F.K. (author), Insuasty, E (author), Van den Hof, PMJ (author), Jansen, J.D. (author)

Closed-loop reservoir management (CLRM) is a combination of life-cycle optimization and computerassisted history matching. The application of the CLRM framework to real field cases can be computationally demanding. An even higher computational load results from procedures to assess the value of information (VOI) in CLRM. Such procedures, which...

conference paper 2016

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Temporal oscillations in the simulation of foam enhanced oil recovery

van der Meer, J.M. (author), Kraaijevanger, JFBM (author), Möller, M. (author), Jansen, J.D. (author)

Many enhanced oil recovery (EOR) processes can be described using partial differential equations with parameters that are strongly non-linear functions of one or more of the state variables. Typically these nonlinearities result in solution components changing several orders of magnitude over small spatial or temporal distances. The numerical...

conference paper 2016

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Robust optimization of water-flooding in oil reservoirs using risk management tools

Siraj, Mohsin (author), van den Hof, Paul (author), Jansen, J.D. (author)

The theory of risk provides a systematic approach to handling uncertainty with well-defined risk and deviation measures. As the model-based economic optimization of the water-flooding process in oil reservoirs suffers from high levels of uncertainty, the concepts from the theory of risk are highly relevant. In this paper, the main focus is to...

journal article 2016

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A stochastic simplex approximate gradient (StoSAG) for optimization under uncertainty

Fonseca, R.M. (author), Chen, B (author), Jansen, J.D. (author), Reynolds, Albert C. (author)

We consider a technique to estimate an approximate gradient using an ensemble of randomly chosen control vectors, known as Ensemble Optimization (EnOpt) in the oil and gas reservoir simulation community. In particular, we address how to obtain accurate approximate gradients when the underlying numerical mod- els contain uncertain parameters...

journal article 2016

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Vertical ground movements in the Polish and Lithuanian Baltic coastal area as measured by satellite interferometry

Graniczny, M. (author), Cyziene, J. (author), van Leijen, F.J. (author), Minkevicius, W. (author), Mikulenas, V. (author), Satkunas, J. (author), Przylucka, M. (author), Kowalski, Z. (author), Uscinowicz, S. (author), Jeglinski, W. (author), Hanssen, R.F. (author)

The article contains results obtained from realization of the Polish and Lithuanian Baltic case study within the EU – FP 7 SubCoast project, which one of the primary aims was analysis of vertical ground movements, potentially causing geohazards in the coastal areas. To reach this goal Interferometric Synthetic Aperture Radar (InSAR) data were...

journal article 2015

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Dissolution along fracture systems in Turonian-Campanian carbonates in Brazil

Bezerra, F.H.G. (author), Cazarin, C. (author), Nogueira, F. (author), Rabelo, J. (author), Bertotti, G. (author), Bisdom, K. (author), Silva, C. (author), Maia, R. (author)

journal article 2015

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COST action TU1208 "Civil engineering applications of ground penetrating radar:" ongoing research activities and mid-term results

Pajewski, L. (author), Benedetto, A. (author), Loizos, A. (author), Slob, E.C. (author), Tosti, F. (author)

journal article 2015

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Reflection imaging of the Moho and the aseismic Nazca slab in the Malargüe region with global-phase seismic interferometry; abstract

Nishitsuji, Y. (author), Draganov, D.S. (author), Ruigrok, E. (author), Gomez, M. (author), Wapenaar, C.P.A. (author)

conference paper 2015

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The use of a large-strain consolidation model to optimise multilift tailing deposits

Vardon, P.J. (author), Yao, Y. (author), Van Paassen, L.A. (author), Van Tol, A.F. (author)

Thin-lift atmospheric fine drying (AFD) is a technique used to dewater mine and oil sand tailings, which utilises both self-weight consolidation and atmospheric evaporation. The disposed layers undergo a cyclic drying and rewetting process due to precipitation and deposition of additional lifts on top of the dried layer. The current research...

conference paper 2015

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Remote sensing evaluation of fire hazard: Towards operational tools for improving the security of citizens and protecting the environment

Maffei, C. (author), Gambardella, C. (author), Menenti, M. (author)

Forest fires are a threat for both the environment and the security of citizens. This is particularly relevant in the Mediterranean, where the population density is high, and long dry summers drive vegetation into fireprone conditions. Policy makers underline the key role of prevention over damage reparation, and indeed efforts are conducted at...

conference paper 2015

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Applicability of near-infrared hyperspectral imagery (NIR-HI) for sensor based sorting of an epithermal Au-Ag ore

Dalm, M. (author), Buxton, M.W.N. (author), Van Ruitenbeek, F.J.A. (author)

In the presented study test work was performed with near-infrared hyperspectral imagery (NIR-HI) on 36 ore samples from a South-American epithermal Au-Ag mine. The aim of the test work was to investigate if NIR-HI provides information about the alteration mineralogy of samples that can be used to predict their economic value. Mineral...

conference paper 2015

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Detection and location of earthquakes along the west coast of Chile: Examining seismicity in the 2010 M 8.8 Maule and 2014 M 8.1 Iquique earthquake rupture zones; abstract

Diniakos, R.S. (author), Bilek, S.L. (author), Rowe, C.A. (author), Draganov, D.S. (author)

conference paper 2015

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Estimating a continuous p-wave velocity profile with constant squared-slowness gradient models from seismic field data

Ponomarenko, A.V. (author), Kashtan, B.M. (author), Troyan, V.N. (author), Mulder, W.A. (author)

We inverted seismic field data for a continuous, laterally invariant P-wave velocity profile. Instead of the usual approach that involves horizontal layers with piecewise constant densities and velocities, we consider models of one or two layers with a constant gradient of the squared slowness above a homogeneous halfspace. With a single layer...

conference paper 2015

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Seismic reflection imaging, accounting for primary and multiple reflections

Wapenaar, C.P.A. (author), Van der Neut, J.R. (author), Thorbecke, J.W. (author), Broggini, F. (author), Slob, E.C. (author), Snieder, R. (author)

journal article 2015

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Ensemble-based multiobjective optimization of on/off control devices under geological uncertainty

Fonseca, R.M. (author), Leeuwenburgh, O. (author), Della Rossa, E (author), van den Hof, P.M.J. (author), Jansen, J.D. (author)

We consider robust ensemble-based (EnOpt) multiobjective production optimization of on/off inflow-control devices (ICDs) for a sector model inspired by a real-field case. The use of on/off valves as optimization variables leads to a discrete control problem. We propose a reparameterization of such discrete controls in terms of switching times...

conference paper 2015

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Geotechnical Ultimate Limit State Design Using Finite Elements

Brinkgreve, R.B.J. (author), Post, M. (author)

Displacement-based finite element calculations are primarily used for serviceability limit state (SLS) analysis, but the finite element method also offers possibilities for ultimate limit state (ULS) design in geotechnical engineering. The combined use of SLS and ULS calculations with partial safety factors according to the different design...

conference paper 2015

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Detection of Anomalies in Diaphragm Walls

Spruit, R. (author), Van Tol, F. (author), Broere, W. (author)

If a calamity with a retaining wall occurs, the impact on surrounding buildings and infrastructure is at least an order of magnitude more severe than without the calamity. In 2005 and 2006 major leaks in the retaining walls of underground stations in Amsterdam and Rotterdam occurred. After these cases had been thoroughly studied it was concluded...

conference paper 2015

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Concrete Flow in Diaphragm Wall Panels: A Full-Scale In-Situ Test

Van Dalen, J.H. (author), Bosch, J.W. (author), Broere, W. (author)

Flow processes, taking place during the concreting of diaphragm wall panels (D-wall panels), are of great importance for the quality of the wall. During this phase, the bentonite, present in the excavated trench, should be completely replaced by concrete in a controlled way. In literature several cases are described in which this process...

conference paper 2015