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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

For many years, strongly and weakly constrained approaches were the only options to deal with errors in four-dimensional variational data assimilation (4DVar), with the aim of balancing the degrees of freedom and model constraints. Strong…

Atmospheric and Oceanic Physics · Physics 2022-12-21 Xiangjun Tian , Hongqin Zhang , Zhe Jin , Min Zhao , Yilong Wang , Yinhai Luo , Ziqing Zhang , Yanyan Tan

Balanced truncation is a well-established model order reduction method which has been applied to a variety of problems. Recently, a connection between linear Gaussian Bayesian inference problems and the system-theoretic concept of balanced…

Numerical Analysis · Mathematics 2024-01-04 Josie König , Melina A. Freitag

Variational Data Assimilation (DA) has enabled huge improvements in the skill of operational weather forecasting. In this study, we use a simple solar-wind propagation model to develop the first solar-wind variational DA scheme. This scheme…

Space Physics · Physics 2018-10-19 Matthew Lang , Mathew Owens

We present a convolution-based data assimilation method tailored to neuronal electrophysiology, addressing the limitations of traditional value-based synchronization approaches. While conventional methods rely on nudging terms and pointwise…

Neurons and Cognition · Quantitative Biology 2025-06-16 Dawei Li , Henry D. I. Abarbanel

Computational kernel of the three-dimensional variational data assimilation (3D-Var) problem is a linear system, generally solved by means of an iterative method. The most costly part of each iterative step is a matrix-vector product with a…

Numerical Analysis · Computer Science 2014-05-15 S. Cuomo , R. Farina , A. Galletti , L. Marcellino

Data assimilation (DA) is a fundamental computational technique that integrates numerical simulation models and observation data on the basis of Bayesian statistics. Originally developed for meteorology, especially weather forecasting, DA…

Data assimilation (DA) is widely used to combine physical knowledge and observations. It is nowadays commonly used in geosciences to perform parametric calibration. In a context of climate change, old calibrations can not necessarily be…

Machine Learning · Statistics 2021-06-23 Rem-Sophia Mouradi , Cédric Goeury , Olivier Thual , Fabrice Zaoui , Pablo Tassi

This paper presents a practical computational approach to quantify the effect of individual observations in estimating the state of a system. Such an analysis can be used for pruning redundant measurements, and for designing future sensor…

Computational Engineering, Finance, and Science · Computer Science 2013-07-22 Alexandru Cioaca , Adrian Sandu , Eric de Sturler

In this article we develop algorithms for data assimilation based upon a computational time dependent stable/unstable splitting. Our particular method is based upon shadowing refinement and synchronization techniques and is motivated by…

Dynamical Systems · Mathematics 2017-07-31 Bart de Leeuw , Svetlana Dubinkina , Jason Frank , Andrew Steyer , Xuemin Tu , Erik Van Vleck

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…

Quantifying forecast uncertainty is a key aspect of state-of-the-art numerical weather prediction and data assimilation systems. Ensemble-based data assimilation systems incorporate state-dependent uncertainty quantification based on…

Atmospheric and Oceanic Physics · Physics 2023-05-17 Maximiliano A. Sacco , Manuel Pulido , Juan J. Ruiz , Pierre Tandeo

We present a sequential data assimilation algorithm based on the ensemble Kalman inversion to estimate the near-surface shear wave velocity profile and damping when heterogeneous data and a priori information that can be represented in…

Geophysics · Physics 2020-05-07 Elnaz Seylabi , Andrew Stuart , Domniki Asimaki

Variational Data Assimilation (DA) has been broadly used in engineering problems for field reconstruction and prediction by performing a weighted combination of multiple sources of noisy data. In recent years, the integration of deep…

Machine Learning · Computer Science 2023-10-26 Sibo Cheng , Che Liu , Yike Guo , Rossella Arcucci

In order to leverage the information embedded in the background state and observations, covariance matrices modelling is a pivotal point in data assimilation algorithms. These matrices are often estimated from an ensemble of observations or…

Methodology · Statistics 2019-10-22 Sibo Cheng , Jean-Philippe Argaud , Bertrand Iooss , Didier Lucor , Angélique Ponçot

Variational data assimilation technique applied to identification of optimal approximations of derivatives near boundary is discussed in frames of one-dimensional wave equation. Simplicity of the equation and of its numerical scheme allows…

Mathematical Physics · Physics 2015-05-13 Eugene Kazantsev

4D-variational data assimilation is applied to the Lorenz '63 model to introduce a new method for parameter estimation in chaotic climate models. The approach aims to optimise an Earth system model (ESM), for which no adjoint exists, by…

Atmospheric and Oceanic Physics · Physics 2025-04-18 Philip David Kennedy , Abhirup Banerjee , Armin Köhl , Detlef Stammer

Evaluating the neutronic state of the whole nuclear core is a very important topic that have strong implication for nuclear core management and for security monitoring. The core state is evaluated using measurements. Usually, part of the…

Data Analysis, Statistics and Probability · Physics 2011-08-31 Bertrand Bouriquet , Jean-Philippe Argaud , Patrick Erhard , Angélique Ponçot

The nudging data assimilation algorithm is a powerful tool used to forecast phenomena of interest given incomplete and noisy observations. Machine learning is becoming increasingly popular in data assimilation given its ease of computation…

Numerical Analysis · Mathematics 2021-11-24 Harbir Antil , Rainald Löhner , Randy Price

Four-dimensional variational data assimilation (4DVAR) is a cornerstone of numerical weather prediction, but its cost function is difficult to optimize and computationally intensive. We propose a neural field-based reformulation in which…

Machine Learning · Computer Science 2025-09-29 Jaemin Oh