English
Related papers

Related papers: Variational Data-Consistent Assimilation

200 papers

This paper presents a novel centralized, variational data assimilation approach for calibrating transient dynamic models in electrical power systems, focusing on load model parameters. With the increasing importance of inverter-based…

Optimization and Control · Mathematics 2023-11-15 Ahmed Attia , D. Adrian Maldonado , Emil Constantinescu , Mihai Anitescu

We present the mathematical framework of a Domain Decomposition (DD) aproach based on Parallel-in-Time methods (PinT-based approach) for solving the 4D-Var Data Assimilation (DA) model. The main outcome of the proposed DD PinT-based…

Numerical Analysis · Mathematics 2018-07-20 Luisa D'Amore , Rosalba Cacciapuoti

This work develops compressive sampling strategies for computing the dynamic mode decomposition (DMD) from heavily subsampled or output-projected data. The resulting DMD eigenvalues are equal to DMD eigenvalues from the full-state data. It…

Dynamical Systems · Mathematics 2013-12-19 Steven L. Brunton , Joshua L. Proctor , J. Nathan Kutz

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

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

This paper presents a model-free, data-driven control synthesis method called dynamic mode adaptive control (DMAC) for systems whose mathematical models are unavailable or unsuitable for classical control design. The proposed approach…

Systems and Control · Electrical Eng. & Systems 2026-04-30 Parham Oveissi , Ankit Goel

This paper provides a detailed theoretical analysis of methods to approximate the solutions of high-dimensional (>10^6) linear Bayesian problems. An optimal low-rank projection that maximizes the information content of the Bayesian…

Data Analysis, Statistics and Probability · Physics 2019-10-28 Nicolas Bousserez , Daven K. Henze

We propose two new methods based/inspired by machine learning for tabular data and distance-free localization to enhance the covariance estimations in an ensemble data assimilation. The main goal is to enhance the data assimilation results…

Machine Learning · Computer Science 2025-07-31 Vinicius L. S. Silva , Gabriel S. Seabra , Alexandre A. Emerick

A nonlinear ensemble-variational (EnVar) data assimilation is performed in order to estimate the unknown flow field over a slender cone at Mach-6, from isolated wall-pressure measurements. The cost functional accounts for discrepancies in…

Fluid Dynamics · Physics 2022-09-14 David A. Buchta , Stuart J. Laurence , Tamer A. Zaki

We formulate a novel approach to solve a class of stochastic problems, referred to as data-consistent inverse (DCI) problems, which involve the characterization of a probability measure on the parameters of a computational model whose…

Numerical Analysis · Mathematics 2024-04-19 Kirana Bergstrom , Troy Butler , Tim Wildey

Data assimilation (DA) in the geophysical sciences remains the cornerstone of robust forecasts from numerical models. Indeed, DA plays a crucial role in the quality of numerical weather prediction, and is a crucial building block that has…

This paper presents a comparison of two reduced-order, sequential and variational data assimilation methods: the SEEK filter and the R-4D-Var. A hybridization of the two, combining the variational framework and the sequential evolution of…

Geophysics · Physics 2009-11-13 Céline Robert , Eric Blayo , Jacques Verron

Harmonic instability occurs frequently in the power electronic converter system. This paper leverages multi-resolution dynamic mode decomposition (MR-DMD) as a data-driven diagnostic tool for the system stability of power electronic…

Signal Processing · Electrical Eng. & Systems 2024-04-16 Rui Kong , Subham Sahoo , Yongjie Liu , Frede Blaabjerg

Estimating covariance matrix from massive high-dimensional and distributed data is significant for various real-world applications. In this paper, we propose a data-aware weighted sampling based covariance matrix estimator, namely DACE,…

Machine Learning · Computer Science 2020-10-13 Xixian Chen , Haiqin Yang , Shenglin Zhao , Michael R. Lyu , Irwin King

A novel linear classification method that possesses the merits of both the Support Vector Machine (SVM) and the Distance-weighted Discrimination (DWD) is proposed in this article. The proposed Distance-weighted Support Vector Machine method…

Machine Learning · Statistics 2015-10-09 Xingye Qiao , Lingsong Zhang

We present an efficient computational framework to quantify the impact of individual observations in four dimensional variational data assimilation. The proposed methodology uses first and second order adjoint sensitivity analysis, together…

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

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

Dynamic mode decomposition (DMD) is a data-driven method that models high-dimensional time series as a sum of spatiotemporal modes, where the temporal modes are constrained by linear dynamics. For nonlinear dynamical systems exhibiting…

Dynamical Systems · Mathematics 2019-06-17 Seth M. Hirsh , Kameron Decker Harris , J. Nathan Kutz , Bingni W. Brunton

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

The work discussed and presented in this paper focuses on the history matching of reservoirs by integrating 4D seismic data into the inversion process using machine learning techniques. A new integrated scheme for the reconstruction of…

Image and Video Processing · Electrical Eng. & Systems 2019-05-21 Clement Etienam