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Related papers: Data assimilation for stratified convection

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Several cardiovascular diseases are caused from localised abnormal blood flow such as in the case of stenosis or aneurysms. Prevailing theories propose that the development is caused by abnormal wall-shear stress in focused areas.…

Optimization and Control · Mathematics 2016-07-12 S. W. Funke , M. Nordaas , Øyvind Evju , M. S. Alnæs , K. -A. Mardal

We develop, analyze, and test an approximate, global data assimilation/synchronization algorithm based on purely local observations for the two-dimensional Navier-Stokes equations on the torus. We prove that, for any error threshold, if the…

Analysis of PDEs · Mathematics 2020-08-18 Animikh Biswas , Zachary Bradshaw , Michael S. Jolly

Stellar evolution codes play a major role in present-day astrophysics, yet they share common simplifications related to the outer layers of stars. We seek to improve on this by the use of results from realistic and highly detailed 3D…

We consider a recently introduced continuous data assimilation (CDA) approach for downscaling a coarse resolution configuration of the 2D Benard convection equations into a finer grid. In this CDA, a nudging term, estimated as the misfit…

Optimization and Control · Mathematics 2015-12-22 M. U. Altaf , E. S. Titi , O. M. Knio , L. Zhao , M. F. McCabe , I. Hoteit

Obtaining accurate high-resolution representations of model outputs is essential to describe the system dynamics. In general, however, only spatially- and temporally-coarse observations of the system states are available. These observations…

Dynamical Systems · Mathematics 2022-11-08 Mohamad Abed El Rahman Hammoud , Olivier LeMaitre , Edriss S. Titi , Ibrahim Hoteit , Omar Knio

In meteorology, engineering and computer sciences, data assimilation is routinely employed as the optimal way to combine noisy observations with prior model information for obtaining better estimates of a state, and thus better forecasts,…

Geophysics · Physics 2009-08-12 M. J. Werner , K. Ide , D. Sornette

Many dynamical systems are difficult or impossible to model using high fidelity physics based models. Consequently, researchers are relying more on data driven models to make predictions and forecasts. Based on limited training data,…

Chaotic Dynamics · Physics 2025-04-09 Max M. Chumley , Firas A. Khasawneh

This paper investigates the use of stratified sampling as a variance reduction technique for approximating integrals over large dimensional spaces. The accuracy of this method critically depends on the choice of the space partition, the…

Probability · Mathematics 2009-09-15 Pierre Etoré , Gersende Fort , Benjamin Jourdain , Eric Moulines

Data Assimilation is the process in which we improve the representation of the state of a physical system by combining information coming from a numerical model, real-world observations, and some prior modelling. It is widely used to model…

Optimization and Control · Mathematics 2025-01-09 Victor Trappler , Arthur Vidard

This paper addresses the impact of assimilating data from the Earth Networks Total Lightning Network (ENTLN) during two cases of severe weather. Data from the ENTLN serve as a substitute for those from the upcoming launch of the GOES…

Optimization and Control · Mathematics 2013-06-11 Razvan Stefanescu , I. Michael Navon , Henry Fuelberg , Max Marchand

We propose an improvement of an oceanographic three dimensional variational assimilation scheme (3D-VAR), named OceanVar, by introducing a recursive filter (RF) with the third order of accuracy (3rd-RF), instead of a RF with first order of…

Numerical Analysis · Computer Science 2015-05-20 R. Farina , S. Dobricic , A. Storto , S. Masina , S. Cuomo

Data assimilation is a central problem in many geophysical applications, such as weather forecasting. It aims to estimate the state of a potentially large system, such as the atmosphere, from sparse observations, supplemented by prior…

Machine Learning · Computer Science 2024-06-24 Matthieu Blanke , Ronan Fablet , Marc Lelarge

The thermal management of cryogenic storage tanks requires advanced control strategies to minimize the boil-off losses produced by heat leakages and sloshing-enhanced heat and mass transfer. This work presents a data-assimilation approach…

Fluid Dynamics · Physics 2025-04-02 Pedro Afonso Marques , Samuel Ahizi , Miguel Alfonso Mendez

There is an urgent need to build models to tackle Indoor Air Quality issue. Since the model should be accurate and fast, Reduced Order Modelling technique is used to reduce the dimensionality of the problem. The accuracy of the model, that…

This paper discusses the practical use of the saddle variational formulation for the weakly-constrained 4D-VAR method in data assimilation. It is shown that the method, in its original form, may produce erratic results or diverge because of…

Numerical Analysis · Mathematics 2021-05-31 S. Gratton , S. Gürol , E. Simon , Ph. L. Toint

Data assimilation leads naturally to a Bayesian formulation in which the posterior probability distribution of the system state, given the observations, plays a central conceptual role. The aim of this paper is to use this Bayesian…

Data Analysis, Statistics and Probability · Physics 2013-01-01 K. J. H. Law , A. M. Stuart

Data assimilation is widely used in many disciplines such as meteorology, oceanography, and robotics to estimate the state of a dynamical system from noisy observations. In this work, we propose a lightweight and general method to perform…

Machine Learning · Computer Science 2025-10-02 Thomas Savary , François Rozet , Gilles Louppe

This paper develops a computational framework for optimizing the parameters of data assimilation systems in order to improve their performance. The approach formulates a continuous meta-optimization problem for parameters; the…

Computational Engineering, Finance, and Science · Computer Science 2015-06-16 Alexandru Cioaca , Adrian Sandu

We describe a new approach allowing for systematic causal attribution of weather and climate-related events, in near-real time. The method is purposely designed to facilitate its implementation at meteorological centers by relying on data…

Relevant comprehension of flood hazards has emerged as a crucial necessity, especially as the severity and the occurrence of flood events intensify with climate changes. Flood simulation and forecast capability have been greatly improved…

Image and Video Processing · Electrical Eng. & Systems 2022-11-18 Thanh Huy Nguyen , Anthéa Delmotte , Christophe Fatras , Peter Kettig , Andrea Piacentini , Sophie Ricci