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Mohsan, M. (author), Vardon, P.J. (author), Vossepoel, F.C. (author)Data assimilation methods have been implemented on a slope stability problem, and the performance of different constitutive models and data assimilation schemes has been investigated. In the first part, a data assimilation scheme called the ensemble Kalman filter (EnKF) is implemented using a finite element model (FEM) and its performance with...conference paper 2023
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Yarce Botero, A. (author), Lopez Restrepo, S. (author), Sebastian Rodriguez, Juan (author), Valle, Diego (author), Galvez-Serna, Julian (author), Montilla, Elena (author), Botero, Francisco (author), Henzing, Bas (author), Heemink, A.W. (author)The densest network for measuring air pollutant concentrations in Colombia is in Medellin, where most sensors are located in the heavily polluted lower parts of the valley. Measuring stations in the higher elevations on the mountains surrounding the valley are not available, which limits our understanding of the valley’s pollutant dynamics and...journal article 2023
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van Hemert, Guus (author)To study the aerosols in the atmosphere is an important aspect for getting a better understanding of climate change. Therefore, it is important to get accurate observations of aerosols in the atmosphere as well as accurate emission fluxes of aerosol species. Satellite instruments such as SPEXone are able to measure aerosol properties with a high...master thesis 2022
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Lopez Restrepo, S. (author), Yarce Botero, A. (author), Pinel, Nicolás (author), Quintero, O. L. (author), Segers, Arjo (author), Heemink, A.W. (author)This work proposes a robust and non-Gaussian version of the shrinkage-based knowledge-aided EnKF implementation called Ensemble Time Local H<sub>∞</sub> Filter Knowledge-Aided (EnTLHF-KA). The EnTLHF-KA requires a target covariance matrix to integrate previously obtained information and knowledge directly into the data assimilation (DA). The...journal article 2022
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De Lannoy, Gabriëlle J.M. (author), Bechtold, Michel (author), Albergel, Clément (author), Brocca, Luca (author), Calvet, Jean Christophe (author), Carrassi, Alberto (author), Crow, Wade T. (author), de Rosnay, Patricia (author), Steele-Dunne, S.C. (author)The beginning of the 21<sup>st</sup> century is marked by a rapid growth of land surface satellite data and model sophistication. This offers new opportunities to estimate multiple components of the water cycle via satellite-based land data assimilation (DA) across multiple scales. By resolving more processes in land surface models and by...review 2022
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Cakir, B.O. (author), Gonzalez Saiz, G. (author), Sciacchitano, A. (author), van Oudheusden, B.W. (author)Three-dimensional Lagrangian particle tracking measurements with helium filled soap bubbles provide quantitative flow visualizations in large measurement volumes up to the cubic metre scale. However, the instantaneously available fluid information density is severely restricted by the finite spatial resolution of the measurements. Therefore,...journal article 2022
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Huang, Yilin (author), Xie, Xu (author), Cho, Yubin (author), Verbraeck, A. (author)Data assimilation (DA) is a methodology widely used by different disciplines of science and engineering. It is typically applied to continuous systems with numerical models. The application of DA to discrete-event and discrete-time systems including agent-based models is relatively new. Because of its non-linearity and non-Gaussianity, the...journal article 2022
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Kumar, Sujay (author), Kolassa, Jana (author), Reichle, Rolf (author), Crow, Wade (author), de Lannoy, Gabrielle (author), de Rosnay, Patricia (author), MacBean, Natasha (author), Quaife, Tristan (author), Steele-Dunne, S.C. (author)The task of quantifying spatial and temporal variations in terrestrial water, energy, and vegetation conditions is challenging due to the significant complexity and heterogeneity of these conditions, all of which are impacted by climate change and anthropogenic activities. To address this challenge, Earth Observations (EOs) of the land and...review 2022
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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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O'Hara, Kian (author)In light of our depleting fossil fuel reserves and the relatively `cheap' extraction of oil and in spite of the highly nonlinear nature of reservoirs, waterflooding has become big business. In recent times, the use of numerical reservoir simulation has not only become possible but has increasingly been used in the petroleum industry in the...master thesis 2021
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Lopez Restrepo, S. (author)In order to avoid the adverse effects of air pollution, efforts have been made to monitor when air pollution reaches dangerous levels. A Chemical Transport Model (CTM) can simulate trace gases and particles concentration in specific areas. These models are not entirely reliable, owing to incomplete knowledge about emissions and meteorological...doctoral thesis 2021
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Mol, Maaike (author)The need for accurate estimation of hydrodynamic and water quality model variables arises from the UNITED project, which aims to create high-resolutional forecasting systems for monitoring the cultivation of seaweed and flat oysters and operating of the Belgian pilot of UNITED in the coastal area of the North Sea. Accurate observations of...master thesis 2021
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Kuipers, Lucas (author)Being able to timely access and share accurate information to all stakeholders that can influence a supply chain is referred to as <i>supply chain visibility</i>. Supply chain visibility is crucial for increasing the resilience of a...master thesis 2021
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Wang, Z. (author)This dissertation's ultimate goal is to provide solutions to two problems that the promising data assimilation method, called the Particle Filter, has when applied to high dimensional non-linear models, such as those often used in hydrological research and forecasting. Two local particle filters have been proposed to overcome three major issues....doctoral thesis 2021
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Belligoli, Z. (author)The continuous increase in the number of flights in the last decades caused a steepgrowth of aviation-related pollution to the point that the aviation sector is responsible for3% of the global greenhouse gas emissions. Regulators have been slow at catching up withthis problem, and stringent emission targets have been put in place only very...doctoral thesis 2021
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Xiao, C. (author)In the community of petroleum engineering, the use of surrogate modelling techniques have recently gained more and more popularity to improve the efficiency of history matching. However, it is still not possible to fully utilize their potential in realistic applications. One of the challenges is to retain high accuracy while increasing the...doctoral thesis 2021
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Yarce Botero, A. (author), Lopez Restrepo, S. (author), Pinel Pelaez, N. (author), Quintero-Montoya, Olga (author), Segers, Arjo (author), Heemink, A.W. (author)In this work, we present the development of a 4D-Ensemble-Variational (4DEnVar) data assimilation technique to estimate NOx top-down emissions using the regional chemical transport model LOTOS-EUROS with the NO2 observations from the TROPOspheric Monitoring Instrument (TROPOMI). The assimilation was performed for a domain in the northwest of...journal article 2021
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Evensen, Geir (author), Amezcua, Javier (author), Bocquet, Marc (author), Carrassi, Alberto (author), Farchi, Alban (author), Fowler, Alison (author), Houtekamer, Pieter L. (author), Jones, Christopher K. (author), Vossepoel, F.C. (author)This work demonstrates the efficiency of using iterative ensemble smoothers to estimate the parameters of an SEIR model. We have extended a standard SEIR model with age-classes and compartments of sick, hospitalized, and dead. The data conditioned on are the daily numbers of accumulated deaths and the number of hospitalized. Also, it is possible...journal article 2021
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Mider, Marcin (author), Schauer, Moritz (author), van der Meulen, F.H. (author)Suppose X is a multivariate diffusion process that is observed discretely in time. At each observation time, a transformation of the state of the process is observed with noise. The smoothing problem consists of recovering the path of the process, consistent with the observations. We derive a novel Markov Chain Monte Carlo algorithm to sample...journal article 2021
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- Leeuwenburgh, O. (author), Emerick, Alexandre A. (author), Jafarpour, Behnam (author), Zhang, Dongxiao (author), Luo, Xiaodong (author) contribution to periodical 2021