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Related papers: Parameter analysis in continuous data assimilation…

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This paper is concerned with the large time behavior of the solutions to the Cauchy problem for the one-dimensional compressible Navier-Stokes/Allen-Cahn system with the immiscible two-phase flow initially located near the phase separation…

Analysis of PDEs · Mathematics 2024-07-08 Yazhou Chen , Qiaolin He , Xiaoding Shi

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 a "data assimilation window" separate from the observational…

Analysis of PDEs · Mathematics 2023-03-08 Adam Larios , Yuan Pei , Collin Victor

Data assimilation is a method that combines observations (that is, real world data) of a state of a system with model output for that system in order to improve the estimate of the state of the system and thereby the model output. The model…

Numerical Analysis · Mathematics 2020-05-18 Melina A. Freitag

An algorithm for continuous data assimilation for the two- dimensional B\'enard convection problem is introduced and analyzed. It is inspired by the data assimilation algorithm developed for the Navier-Stokes equations, which allows for the…

Analysis of PDEs · Mathematics 2015-05-20 Aseel Farhat , Michael S. Jolly , Edriss S. Titi

We study prediction-assimilation systems, which have become routine in meteorology and oceanography and are rapidly spreading to other areas of the geosciences and of continuum physics. The long-term, nonlinear stability of such a system…

Chaotic Dynamics · Physics 2009-11-13 Alberto Carrassi , Michael Ghil , Anna Trevisan , Francesco Uboldi

In this paper, we consider a damped Navier-Stokes-Bardina model posed on the whole three-dimensional. These equations have an important physical motivation and they arise from some oceanic model. From the mathematical point of view, they…

Analysis of PDEs · Mathematics 2021-07-27 Manuel Fernando Cortez , Oscar Jarrín

Data assimilation methodologies are designed to incorporate noisy observations of a physical system into an underlying model in order to infer the properties of the state of the system. Filters refer to a class of data assimilation…

Optimization and Control · Mathematics 2013-08-06 C. E. A. Brett , K. F. Lam , K. J. H. Law , D. S. McCormick , M. R. Scott , A. M. Stuart

Continuous data assimilation (CDA) techniques, most notably the nudging approach proposed by Azouani, Olson, and Titi (AOT), have been shown to be very successful in deterministic frameworks for achieving long-time synchronization between…

Probability · Mathematics 2026-04-20 Kush Kinra

We provide rigorous asymptotic models for the free boundary Darcy and Forchheimer problem under the assumption of weak nonlinear interaction, in a regime in which the steepness parameter of the interface is considered to be very small. The…

Analysis of PDEs · Mathematics 2019-08-15 Rafael Granero-Belinchón , Stefano Scrobogna

Many real-world systems modeled using differential equations involve unknown or uncertain parameters. Standard approaches to address parameter estimation inverse problems in this setting typically focus on estimating constants; yet some…

Dynamical Systems · Mathematics 2024-03-25 Anna Fitzpatrick , Molly Folino , Andrea Arnold

We present some new results on the dynamic regressor extension and mixing parameter estimators for linear regression models recently proposed in the literature. This technique has proven instrumental in the solution of several open problems…

Systems and Control · Electrical Eng. & Systems 2019-08-15 Romeo Ortega , Stanislav Aranovskiy , Anton A. Pyrkin , Alessandro Astolfi , Alexey A. Bobtsov

Based on a previously introduced downscaling data assimilation algorithm, which employs a nudging term to synchronize the coarse mesh spatial scales, we construct a determining map for recovering the full trajectories from their…

Analysis of PDEs · Mathematics 2018-01-04 Animikh Biswas , Ciprian Foias , Cecilia F. Mondaini , Edriss S. Titi

In this paper, we extend $\overline\partial$ steepest descent method to study the Cauchy problem for the nonlocal nonlinear Schr\"odinger (NNLS) equation with weighted Sobolev initial data %and finite density initial data \begin{align*}…

Analysis of PDEs · Mathematics 2023-11-28 Gaozhan Li , Yiling Yang , Engui Fan

We study the use of the Azouani-Olson-Titi (AOT) continuous data assimilation algorithm to recover solutions of the Navier--Stokes equations modified to have higher-order fractional diffusion. The fractional diffusion case is of particular…

Analysis of PDEs · Mathematics 2023-07-04 Adam Larios , Collin Victor

We analyze the long-time asymptotics for the Degasperis--Procesi equation on the half-line. By applying nonlinear steepest descent techniques to an associated $3 \times 3$-matrix valued Riemann--Hilbert problem, we find an explicit formula…

Analysis of PDEs · Mathematics 2018-01-15 A. Boutet de Monvel , J. Lenells , D. Shepelsky

In this paper, we provide conditions, \emph{based solely on the observed data}, for the global well-posedness, regularity and convergence of the Azouni-Olson-Titi data assimilation algorithm (AOT algorithm) for a Leray-Hopf weak solutions…

Analysis of PDEs · Mathematics 2020-03-04 Animikh Biswas , Randy Price

This study addresses the well-posedness of a hemivariational inequality derived from the convective Brinkman-Forchheimer extended Darcy (CBFeD) model in both two and three dimensions. The CBFeD model describes the behavior of incompressible…

Analysis of PDEs · Mathematics 2025-09-12 Manil T. Mohan

This paper is concerned with the large-time behavior of solutions to the Cauchy problem on the two-fluid Euler-Maxwell system with collisions when initial data are around a constant equilibrium state. The main goal is the rigorous…

Analysis of PDEs · Mathematics 2014-12-02 Renjun Duan , Qingqing Liu , Changjiang Zhu

In this paper we study the long time behavior for a semilinear wave equation with space-dependent and nonlinear damping term. After rewriting the equation as a first order system, we define a class of approximate solutions that employ…

Analysis of PDEs · Mathematics 2018-12-24 Debora Amadori , Fatima Al-Zahrà Aqel , Edda Dal Santo

In this study, we conduct parameter estimation analysis on a data assimilation algorithm for two turbulence models: the simplified Bardina model and the Navier-Stokes-{\alpha} model. Our approach involves creating an approximate solution…

Fluid Dynamics · Physics 2024-09-06 Debora A. F. Albanez , Maicon Jose Benvenutti , Samuel Little , Jing Tian