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Xiao, C. (author), Lin, H.X. (author), Leeuwenburgh, O. (author), Heemink, A.W. (author)History matching can play a key role in improving geological characterization and reducing the uncertainty of reservoir model predictions. Application of reservoir history matching is restricted by the huge computational cost by amongst others the many runs of the full model. Surrogate models with a reduced complexity are therefore used to...journal article 2022
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Xiao, C. (author), Leeuwenburgh, O. (author), Lin, H.X. (author), Heemink, A.W. (author)Imaging-type monitoring techniques are used in monitoring dynamic processes in many domains, including medicine, engineering, and geophysics. This paper aims to propose an efficient workflow for application of such data for the conditioning of simulation models. Such applications are very common in e.g. the geosciences, where large-scale...journal article 2021
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Jin, J. (author), Segers, Arjo (author), Lin, H.X. (author), Henzing, Bas (author), Wang, X. (author), Heemink, A.W. (author), Liao, Hong (author)When calibrating simulations of dust clouds, both the intensity and the position are important. Intensity errors arise mainly from uncertain emission and sedimentation strengths, while position errors are attributed either to imperfect emission timing or to uncertainties in the transport. Though many studies have been conducted on the...journal article 2021
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Jin, J. (author), Segers, Arjo (author), Liao, Hong (author), Heemink, A.W. (author), Kranenburg, Richard (author), Lin, H.X. (author)Emission inversion using data assimilation fundamentally relies on having the correct assumptions about the emission background error covariance. A perfect covariance accounts for the uncertainty based on prior knowledge and is able to explain differences between model simulations and observations. In practice, emission uncertainties are...journal article 2020
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Jin, J. (author), Segers, Arjo (author), Heemink, A.W. (author), Yoshida, Mayumi (author), Han, Wei (author), Lin, H.X. (author)Aerosol optical depths (AODs) from the new Himawari-8 satellite instrument have been assimilated in a dust simulation model over East Asia. This advanced geostationary instrument is capable of monitoring the East Asian dust storms which usually have great spatial and temporal variability. The quality of the data has been verified through a...journal article 2019
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Jin, J. (author), Lin, H.X. (author), Segers, Arjo (author), Xie, Yu (author), Heemink, A.W. (author)Data assimilation algorithms rely on a basic assumption of an unbiased observation error. However, the presence of inconsistent measurements with nontrivial biases or inseparable baselines is unavoidable in practice. Assimilation analysis might diverge from reality since the data assimilation itself cannot distinguish whether the differences...journal article 2019
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Xiao, C. (author), Leeuwenburgh, O. (author), Lin, H.X. (author), Heemink, A.W. (author)This paper presents a non-intrusive subdomain POD-TPWL (SD POD-TPWL) for reservoir history matching through integrating domain decomposition (DD), proper orthogonal decomposition (POD), radial basis function (RBF) interpolation, and the trajectory piecewise linearization (TPWL). It is an efficient approach for model reduction and linearization...journal article 2018
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Fu, Guangliang (author), Lin, H.X. (author), Heemink, A.W. (author), Lu, S. (author), Segers, Arjo (author), van Velzen, C. (author), Lu, Tongchao (author), Xu, Shiming (author)In this study, we investigate a strategy to accelerate the data assimilation (DA) algorithm. Based on evaluations of the computational time, the analysis step of the assimilation turns out to be the most expensive part. After a study of the characteristics of the ensemble ash state, we propose a mask-state algorithm which records the sparsity...journal article 2017
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Lu, S. (author), Heemink, A.W. (author), Lin, H.X. (author), Segers, Arjo (author), Fu, Guangliang (author)Remote sensing, as a powerful tool for monitoring atmospheric phenomena, has been playing an increasingly important role in inverse modeling. Remote sensing instruments measure quantities that often combine several state variables as one. This creates very strong correlations between the state variables that share the same observation variable....journal article 2017
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Fu, Guangliang (author), Prata, Fred (author), Lin, H.X. (author), Heemink, A.W. (author), Segers, AJ (author), Lu, S. (author)Using data assimilation (DA) to improve model forecast accuracy is a powerful approach that requires available observations. Infrared satellite measurements of volcanic ash mass loadings are often used as input observations for the assimilation scheme. However, because these primary satellite-retrieved data are often two-dimensional (2-D) and...journal article 2017
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Lu, S. (author), Lin, H.X. (author), Heemink, A.W. (author), Segers, Arjo (author), Fu, Guangliang (author)In this paper, we reconstruct the vertical profile of volcanic ash emissions by assimilating satellite data and ground-based observations using a modified trajectory-based 4D-Var (Trj4DVar) approach. In our previous work, we found that the lack of vertical resolution in satellite ash column data can result in a poor estimation of the injection...journal article 2016
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Fu, Guangliang (author), Heemink, A.W. (author), Lu, S. (author), Segers, AJ (author), Weber, Konradin (author), Lin, H.X. (author)The forecast accuracy of distal volcanic ash clouds is important for providing valid aviation advice during volcanic ash eruption. However, because the distal part of volcanic ash plume is far from the volcano, the influence of eruption information on this part becomes rather indirect and uncertain, resulting in inaccurate volcanic ash forecasts...journal article 2016
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Lu, S. (author), Lin, X. (author), Heemink, A.W. (author), Fu, G. (author), Segers, A.J. (author)Volcanic ash forecasting is a crucial tool in hazard assessment and operational volcano monitoring. Emission parameters such as plume height, total emission mass, and vertical distribution of the emission plume rate are essential and important in the implementation of volcanic ash models. Therefore, estimation of emission parameters using...journal article 2015
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Fu, G. (author), Lin, H.X. (author), Heemink, A.W. (author), Segers, A.J. (author), Lu, S. (author), Palsson, T. (author)The 2010 Eyjafjallajokull volcano eruption had serious consequences to civil aviation. This has initiated a lot of research on volcanic ash transport forecast in recent years. For forecasting the volcanic ash transport after eruption onset, a volcanic ash transport and diffusion model (VATDM) needs to be run with Eruption Source Parameters (ESP)...journal article 2015
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- Fu, G. (author), Lin, H.X. (author), Heemink, A.W. (author), Segers, A. (author), Lu, S. (author), Palsson, T. (author) conference paper 2015
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- Lu, S. (author), Lin, H.X. (author), Heemink, A.W. (author), Segers, A. (author), Fu, G. (author) conference paper 2015
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Huber, E. (author), Spivakovskaya, D. (author), Lin, H.X. (author), Heemink, A.W. (author)Last several years the ship accidents caused the serious ecological catastrophes in the seaside of different countries. To prevent or, at least, reduce the possible damage due to accidents we need to develop efficient and accurate model for the simulation of the pollution spreading. The movement of the pollutant can be modeled by using a random...conference paper 2006
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- Van den Berg, E. (author), Heemink, W. (author), Lin, X. (author), Schoenmakers, J.G.M. (author) journal article 2005
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Van den Berg, E. (author), Heemink, A.W. (author), Lin, H.X. (author), Schoenmakers, J.G.M. (author)The estimation of probability densities of variables described by systems of stochastic dierential equations has long been done using forward time estimators, which rely on the generation of realizations of the model, forward in time. Recently, an estimator based on the combination of forward and reverse time estimators has been developed. This...report 2003