Search Results - "Valstar, Johan"

The impact of aquifer heterogeneity on the performance of aquifer thermal energy storage by Sommer, Wijb, Valstar, Johan, van Gaans, Pauline, Grotenhuis, Tim, Rijnaarts, Huub

“…Heterogeneity in hydraulic properties of the subsurface is not accounted for in current design calculations of aquifer thermal energy storage (ATES). However,…”
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Measurement network design including traveltime determinations to minimize model prediction uncertainty by Jansen, G.M.C.M, Valstar, J.R, Zee, S.E.A.T.M. van der

“…Traveltime determinations have found increasing application in the characterization of groundwater systems. No algorithms are available, however, to optimally…”
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Calibration of Parameter Fields Consisting of Multiple Statistical Populations by Janssen, Gijs M.C.M, Valstar, Johan R

“…If a parameter field to be calibrated consists of more than one statistical population, usually not only the parameter values are uncertain, but the spatial…”
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Inverse modeling of multimodal conductivity distributions by Janssen, G.M.C.M, Valstar, J.R, Zee, S.E.A.T.M. van der

“…We present a method for the calibration of multimodal hydraulic conductivity distributions and apply this method to the particular case of confining layers…”
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A representer-based inverse method for groundwater flow and transport applications by Valstar, Johan R., McLaughlin, Dennis B., te Stroet, Chris B. M., van Geer, Frans C.

“…Groundwater inverse problems are concerned with the estimation of uncertain model parameters, such as hydraulic conductivity, from field or laboratory…”
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Optimization and spatial pattern of large-scale aquifer thermal energy storage by Sommer, Wijbrand, Valstar, Johan, Leusbrock, Ingo, Grotenhuis, Tim, Rijnaarts, Huub

“…•Thermal interference limits large-scale application of ATES.•Efficiency of large-scale ATES systems can be improved by better well placement.•Economic…”
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Dual states estimation of a subsurface flow-transport coupled model using ensemble Kalman filtering by Gharamti, Mohamad El, Hoteit, Ibrahim, Valstar, Johan

“…•We introduce an ensemble dual formulation for coupled states estimation.•An EnKF-based algorithm is derived for assimilation into one-way coupled models.•We…”
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The impact of low-temperature seasonal aquifer thermal energy storage (SATES) systems on chlorinated solvent contaminated groundwater: Modeling of spreading and degradation by Zuurbier, Koen G., Hartog, Niels, Valstar, Johan, Post, Vincent E.A., van Breukelen, Boris M.

“…Groundwater systems are increasingly used for seasonal aquifer thermal energy storage (SATES) for periodic heating and cooling of buildings. Its use is…”
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On the efficiency of the hybrid and the exact second-order sampling formulations of the EnKF: a reality-inspired 3-D test case for estimating biodegradation rates of chlorinated hydrocarbons at the port of Rotterdam by Gharamti, Mohamad E, Valstar, Johan, Janssen, Gijs, Marsman, Annemieke, Hoteit, Ibrahim

“…This study considers the assimilation problem of subsurface contaminants at the port of Rotterdam in the Netherlands. It involves the estimation of solute…”
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Sensitivity analysis on parameters and processes affecting vapor intrusion risk by Picone, Sara, Valstar, Johan, van Gaans, Pauline, Grotenhuis, Tim, Rijnaarts, Huub

“…A one‐dimensional numerical model was developed and used to identify the key processes controlling vapor intrusion risks by means of a sensitivity analysis…”
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The impact of aquifer heterogeneity on the performance of aquifer thermal energy storage: THERMAL ENERGY STORAGE AND HETEROGENEITY by Sommer, Wijb, Valstar, Johan, van Gaans, Pauline, Grotenhuis, Tim, Rijnaarts, Huub

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Toluene biodegradation rates in unsaturated soil systems versus liquid batches and their relevance to field conditions by Picone, Sara, Grotenhuis, Tim, van Gaans, Pauline, Valstar, Johan, Langenhoff, Alette, Rijnaarts, Huub

“…Contaminant biodegradation in unsaturated soils may reduce the risks of vapor intrusion. However, the reported rates show large variability and are often…”
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