Dynamically learning the parameters of a chaotic system using partial observations

E Carlson, J Hudson, A Larios, VR Martinez… - arXiv preprint arXiv …, 2021 - arxiv.org
Motivated by recent progress in data assimilation, we develop an algorithm to dynamically
learn the parameters of a chaotic system from partial observations. Under reasonable …

Super-Exponential Convergence Rate of a Nonlinear Continuous Data Assimilation Algorithm: The 2D Navier–Stokes Equation Paradigm

E Carlson, A Larios, ES Titi - Journal of Nonlinear Science, 2024 - Springer
We study a nonlinear-nudging modification of the Azouani–Olson–Titi continuous data
assimilation (downscaling) algorithm for the 2D incompressible Navier–Stokes equations …

The bleeps, the sweeps, and the creeps: convergence rates for dynamic observer patterns via data assimilation for the 2D Navier–Stokes equations

T Franz, A Larios, C Victor - Computer Methods in Applied Mechanics and …, 2022 - Elsevier
We adapt a continuous data assimilation scheme, known as the Azouani–Olson–Titi (AOT)
algorithm, to the case of moving observers for the 2D incompressible Navier–Stokes …

Continuous data assimilation for the 3D and higher-dimensional Navier–Stokes equations with higher-order fractional diffusion

A Larios, C Victor - Journal of Mathematical Analysis and Applications, 2024 - Elsevier
We study the use of the Azouani-Olson-Titi (AOT) continuous data assimilation algorithm to
recover solutions of the 3D Navier–Stokes equations modified to have finer-order fractional …

The second-best way to do sparse-in-time continuous data assimilation: Improving convergence rates for the 2D and 3D Navier-Stokes equations

A Larios, Y Pei, C Victor - arXiv preprint arXiv:2303.03495, 2023 - arxiv.org
We study different approaches to implementing sparse-in-time observations into the the
Azouani-Olson-Titi data assimilation algorithm. We propose a new method which introduces …

Simple and efficient continuous data assimilation of evolution equations via algebraic nudging

LG Rebholz, C Zerfas - Numerical Methods for Partial …, 2021 - Wiley Online Library
We introduce, analyze, and test an interpolation operator designed for use with continuous
data assimilation (DA) of evolution equations that are discretized spatially with the finite …

[HTML][HTML] Adaptive parameter selection in nudging based data assimilation

A Çıbık, R Fang, W Layton, F Siddiqua - Computer Methods in Applied …, 2025 - Elsevier
Data assimilation combines (imperfect) knowledge of a flow's physical laws with (noisy, time-
lagged, and otherwise imperfect) observations to produce a more accurate prediction of flow …

Identifying the body force from partial observations of a two-dimensional incompressible velocity field

A Farhat, A Larios, VR Martinez, JP Whitehead - Physical Review Fluids, 2024 - APS
Using limited observations of the velocity field of the two-dimensional Navier-Stokes
equations, we successfully reconstruct the steady body force that drives the flow. The …

Continuous data assimilation for the 3D Ladyzhenskaya model: analysis and computations

Y Cao, A Giorgini, M Jolly, A Pakzad - Nonlinear Analysis: Real World …, 2022 - Elsevier
We analyze continuous data assimilation by nudging for the 3D Ladyzhenskaya equations.
The analysis provides conditions on the spatial resolution of the observed data that …

Determining map, data assimilation and an observable regularity criterion for the three-dimensional Boussinesq system

A Balakrishna, A Biswas - Applied Mathematics & Optimization, 2022 - Springer
In this paper, we consider the analysis of a nudging based algorithm for data assimilation for
the three-dimensional Boussinesq system, which we call the AOT system. A rigorous …