Ensemble Kalman methods: a mean field perspective

E Calvello, S Reich, AM Stuart - arxiv preprint arxiv:2209.11371, 2022 - arxiv.org
Ensemble Kalman methods are widely used for state estimation in the geophysical sciences.
Their success stems from the fact that they take an underlying (possibly noisy) dynamical …

[HTML][HTML] An AI-based non-intrusive reduced-order model for extended domains applied to multiphase flow in pipes

CE Heaney, Z Wolffs, JA Tómasson, L Kahouadji… - Physics of …, 2022 - pubs.aip.org
The modeling of multiphase flow in a pipe presents a significant challenge for high-
resolution computational fluid dynamics (CFD) models due to the high aspect ratio (length …

[КНИГА][B] Stochastic Methods for Modeling and Predicting Complex Dynamical Systems

N Chen - 2023 - Springer
Complex dynamical systems are ubiquitous in many areas, including geoscience,
engineering, neural science, material science, etc. Modeling and predicting complex …

Convolutional Neural Network‐Based Adaptive Localization for an Ensemble Kalman Filter

Z Wang, L Lei, JL Anderson, ZM Tan… - Journal of Advances in …, 2023 - Wiley Online Library
Flow‐dependent background error covariances estimated from short‐term ensemble
forecasts suffer from sampling errors due to limited ensemble sizes. Covariance localization …

Deep learning-enhanced ensemble-based data assimilation for high-dimensional nonlinear dynamical systems

A Chattopadhyay, E Nabizadeh, E Bach… - Journal of …, 2023 - Elsevier
Data assimilation (DA) is a key component of many forecasting models in science and
engineering. DA allows one to estimate better initial conditions using an imperfect dynamical …

A machine learning augmented data assimilation method for high‐resolution observations

LJ Howard, A Subramanian… - Journal of Advances in …, 2024 - Wiley Online Library
The accuracy of initial conditions is an important driver of the forecast skill of numerical
weather prediction models. Increases in the quantity of available measurements, particularly …

Spatio‐temporal super‐resolution data assimilation (SRDA) utilizing deep neural networks with domain generalization

Y Yasuda, R Onishi - Journal of Advances in Modeling Earth …, 2023 - Wiley Online Library
Deep learning has recently gained attention in the atmospheric and oceanic sciences for its
potential to improve the accuracy of numerical simulations or to reduce computational costs …

Reduced-order autodifferentiable ensemble kalman filters

Y Chen, D Sanz-Alonso, R Willett - Inverse Problems, 2023 - iopscience.iop.org
This paper introduces a computational framework to reconstruct and forecast a partially
observed state that evolves according to an unknown or expensive-to-simulate dynamical …

Extending the capabilities of data-driven reduced-order models to make predictions for unseen scenarios: applied to flow around buildings

CE Heaney, X Liu, H Go, Z Wolffs, P Salinas… - Frontiers in …, 2022 - frontiersin.org
We present a data-driven or non-intrusive reduced-order model (NIROM) which is capable
of making predictions for a significantly larger domain than the one used to generate the …

Combining stochastic parameterized reduced‐order models with machine learning for data assimilation and uncertainty quantification with partial observations

C Mou, LM Smith, N Chen - Journal of Advances in Modeling …, 2023 - Wiley Online Library
A hybrid data assimilation algorithm is developed for complex dynamical systems with
partial observations. The method starts with applying a spectral decomposition to the entire …