- document
-
Jesus de Moraes, R. (author), Hajibeygi, H. (author), Jansen, J.D. (author)In data assimilation problems, various types of data are naturally linked to different spatial resolutions (e.g., seismic and electromagnetic data), and these scales are usually not coincident to the subsurface simulation model scale. Alternatives like upscaling/downscaling of the data and/or the simulation model can be used, but with...journal article 2020
- document
-
Lu, Y. (author), Steele-Dunne, S.C. (author), De Lannoy, Gabriëlle J.M. (author)Surface heat fluxes are vital to hydrological and environmental studies, but mapping them accurately over a large area remains a problem. In this study, brightness temperature (TB) observations or soil moisture retrievals from the NASA Soil Moisture Active Passive (SMAP) mission and land surface temperature (LST) product from the...journal article 2020
- document
-
Allaerts, D.J.N. (author), Quon, Eliot (author), Draxl, Caroline (author), Churchfield, Matthew (author)Mesoscale-to-microscale coupling (MMC) aims to address the limited scope of traditional large-eddy simulations by driving the microscale flow with information concerning large-scale weather patterns provided by mesoscale models. We present a new offline MMC technique for horizontally homogeneous microscale flow conditions, in which internal...journal article 2020
- document
-
Tangdamrongsub, Natthachet (author), Han, Shin Chan (author), Yeo, In Young (author), Dong, Jianzhi (author), Steele-Dunne, S.C. (author), Willgoose, Garry (author), Walker, Jeffrey P. (author)Assimilating remote sensing observations into land surface models has become common practice to improve the accuracy of terrestrial water storage (TWS) estimates such as soil moisture and groundwater, for understanding the land surface interaction with the climate system, as well as assessing regional and global water resources. Such remote...journal article 2020
- document
-
Mazzoleni, M. (author), Amaranto, A. (author), Solomatine, D.P. (author)This study aims at proposing novel approaches for integrating qualitative flow observations in a lumped hydrologic routing model and assessing their usefulness for improving flood estimation. Routing is based on a three-parameter Muskingum model used to propagate streamflow in five different rivers in the United States. Qualitative flow...journal article 2019
- document
-
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
- document
-
Lu, Y. (author), Dong, Jianzhi (author), Steele-Dunne, S.C. (author)The spatial heterogeneity and temporal variation of soil moisture and surface heat fluxes are key to many geophysical and environmental studies. It has been demonstrated that they can be mapped by assimilating soil thermal and wetness information into surface energy balance models. The aim of this work is to determine whether enhancing the...journal article 2019
- document
-
Li, Bailing (author), Rodell, Matthew (author), Kumar, Sujay (author), Beaudoing, Hiroko Kato (author), Getirana, Augusto (author), Zaitchik, Benjamin F. (author), de Goncalves, Luis Gustavo (author), Cossetin, Camila (author), Steele-Dunne, S.C. (author)The scarcity of groundwater storage change data at the global scale hinders our ability to monitor groundwater resources effectively. In this study, we assimilate a state-of-the-art terrestrial water storage product derived from Gravity Recovery and Climate Experiment (GRACE) satellite observations into NASA's Catchment land surface model ...journal article 2019
- document
-
Liu, K. (author), Vardon, P.J. (author), Hicks, M.A. (author)A data assimilation framework, utilising measurements of pore water pressure to sequentially improve the estimation of soil hydraulic parameters and, in turn, the prediction of slope stability, is proposed. Its effectiveness is demonstrated for an idealised numerical example involving the spatial variability of saturated hydraulic...journal article 2018
- document
-
Xie, X. (author), van Lint, J.W.C. (author), Verbraeck, A. (author)With trajectory data, a complete microscopic and macroscopic picture of traffic flow operations can be obtained. However, trajectory data are difficult to observe over large spatiotemporal regions—particularly in urban contexts—due to practical, technical and financial constraints. The next best thing is to estimate plausible trajectories from...journal article 2018
- document
-
Schwarz, Alexander (author), Dwight, R.P. (author)We investigate theoretically and numerically the use of the least-squares finite-element method (LSFEM) to approach data-assimilation problems for the steady-state, incompressible Navier-Stokes equations. Our LSFEM discretization is based on a stress-velocity-pressure (S-V-P) first-order formulation, using discrete counterparts of the Sobolev...journal article 2018
- document
-
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
- document
-
Wambeke, T. (author), Benndorf, J. (author)The mining industry continuously struggles to keep produced tonnages and grades aligned with targets derived from model-based expectations. Deviations often result from the inability to characterise short-term production units accurately based on sparsely distributed exploration data. During operation, the characterisation of short-term...journal article 2018
- document
-
Jesus de Moraes, R. (author), Rodrigues, José R.P. (author), Hajibeygi, H. (author), Jansen, J.D. (author)A generic framework for the computation of derivative information required for gradient-based optimization using sequentially coupled subsurface simulation models is presented. The proposed approach allows for the computation of any derivative information with no modification of the mathematical framework. It only requires the forward model...journal article 2018
- document
-
Xie, X. (author), Verbraeck, A. (author)With the advent of new sensor technologies and communication solutions, the availability of data for discrete event systems has greatly increased. This motivates research on data assimilation for discrete event simulations that has not yet fully matured. This paper presents a particle filter-based data assimilation framework for discrete event...journal article 2018
- document
-
Dhadly, Manbharat S. (author), Emmert, John T. (author), Drob, Douglas P. (author), Conde, Mark G. (author), Doornbos, E.N. (author), Shepherd, Gordon (author), Makela, Jonathan (author), Wu, Qian (author), Nieciejewski, Richard J. (author), Ridley, Aaron J. (author)This study is focused on improving the poorly understood seasonal dependence of northern high-latitude F region thermospheric winds under active geomagnetic conditions. The gaps in our understanding of the dynamic high-latitude thermosphere are largely due to the sparseness of thermospheric wind measurements. With current observational...journal article 2018
- document
-
Slobbe, D.C. (author), Sumihar, JH (author), Frederikse, T. (author), Verlaan, M. (author), Klees, R. (author), Zijl, F (author), Hashemi Farahani, H. (author), Broekman, R (author)In this paper, we present a novel Kalman filter approach to combine a hydrodynamic model-derived lowest astronomical tide (LAT) surface with tide gauge record-derived LAT values. In the approach, tidal water levels are assimilated into the model. As such, the combination is guided by the model physics. When validating the obtained “Kalman...journal article 2017
- document
-
Duret, Aurélien (author), Yuan, Y. (author)The paper proposes a model-based framework for estimating traffic states from Eulerian (loop) and/or Lagrangian (probe) data. Lagrangian-Space formulation of the LWR model adopted as the underlying traffic model provides suitable properties for receiving both Eulerian and Lagrangian external information. Three independent methods are proposed...journal article 2017
- document
-
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
- document
-
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