English
Related papers

Related papers: Controlling instabilities along a 3DVar analysis c…

200 papers

Four-dimensional variational data assimilation (4DVar) has become an increasingly important tool in data science with wide applications in many engineering and scientific fields such as geoscience1-12, biology13 and the financial…

Data Analysis, Statistics and Probability · Physics 2018-05-28 Xiangjun Tian , Aiguo Dai , Xiaobing Feng , Hongqin Zhang , Rui Han , Lu Zhang

Anomaly detection in multivariate time series (MTS) is hindered by dynamic inter-variable dependencies and feature entanglement under spectral noise, and in practice, is further complicated by the absence of anomaly labels. Existing…

Machine Learning · Computer Science 2026-05-25 Yunhua Pei , Zixing Song , Jin Zheng , John Cartlidge

A Data Assimilation (DA) strategy based on an ensemble Kalman filter (EnKF) is used to enhance the predictive capabilities of scale resolving numerical tools for the analysis of flows exhibiting cyclic behaviour. More precisely, an ensemble…

Fluid Dynamics · Physics 2025-03-20 Lucas Villanueva , Karine Truffin , Jacques Borée , Marcello Meldi

This paper presents a novel fusion technique for LiDAR Simultaneous Localization and Mapping (SLAM), aimed at improving localization and 3D mapping using LiDAR sensor. Our approach centers on the Inferred Attention Fusion (INAF) module,…

Robotics · Computer Science 2025-10-20 Zahra Arjmandi , Gunho Sohn

A main problem in autonomous vehicles in general, and in \acp{UAV} in particular, is the determination of the attitude angles. A novel method to estimate these angles using off-the-shelf components is presented. This paper introduces an…

Variational data assimilation in continuous time is revisited. The central techniques applied in this paper are in part adopted from the theory of optimal nonlinear control. Alternatively, the investigated approach can be considered as a…

Atmospheric and Oceanic Physics · Physics 2015-05-18 Jochen Bröcker

The Ensemble Kalman filter assumes the observations to be Gaussian random variables with a pre-specified mean and variance. In practice, observations may also have detection limits, for instance when a gauge has a minimum or maximum value.…

Optimization and Control · Mathematics 2018-11-14 Abhishek Shah , Mohamad El Gharamti , Laurent Bertino

This study develops a hybrid ensemble-variational approach for solving data assimilation problems. The method, called TR-4D-EnKF, is based on a trust region framework and consists of three computational steps. First an ensemble of model…

Numerical Analysis · Computer Science 2015-02-03 Elias D. Nino , Adrian Sandu

Variational data assimilation and machine-learning based super-resolution are two alternative approaches to state estimation in turbulent flows. The former is an optimisation problem featuring a time series of coarse observations, the…

Fluid Dynamics · Physics 2025-10-21 Markus Weyrauch , Moritz Linkmann , Jacob Page

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

In this paper, we investigate joint unmanned aerial vehicle (UAV) formation and resource allocation optimization for communication-assisted three-dimensional (3D) synthetic aperture radar (SAR) sensing. We consider a system consisting of…

Signal Processing · Electrical Eng. & Systems 2025-02-10 Mohamed-Amine Lahmeri , Víctor Mustieles-Pérez , Martin Vossiek , Gerhard Krieger , Robert Schober

In three-dimensional variational data assimilation (3DVar) for numerical weather prediction (NWP), the observation operator $\mathcal{H}$ plays a central role by mapping model state variables to an observation equivalent. For weather radar,…

Atmospheric and Oceanic Physics · Physics 2025-12-23 Marco Stefanelli , Žiga Zaplotnik , Gregor Skok

LiDAR-based 3D perception and localization on unmanned aerial vehicles (UAVs) are fundamentally limited by the narrow field of view (FoV) of compact LiDAR sensors and the payload constraints that preclude multi-sensor configurations.…

Robotics · Computer Science 2025-09-12 Jianping Li , Xinhang Xu , Zhongyuan Liu , Shenghai Yuan , Muqing Cao , Lihua Xie

In data assimilation, the model may be subject to uncertainties and errors. The weak-constraint data assimilation framework enables incorporating model uncertainty in the dynamics of the governing equations. We propose a new framework for…

Numerical Analysis · Mathematics 2025-12-23 Alen Alexanderian , Hugo Díaz , Vishwas Rao , Arvind K. Saibaba

Unmanned Aerial Vehicles (UAV) have emerged as versatile platforms, driving the demand for accurate modeling to support developmental testing. This paper proposes data-driven modeling software for UAV. Emphasizes the utilization of…

Data assimilation (DA) plays a pivotal role in diverse applications, ranging from climate predictions and weather forecasts to trajectory planning for autonomous vehicles. A prime example is the widely used ensemble Kalman filter (EnKF),…

Dynamical Systems · Mathematics 2024-01-03 Mohamad Abed El Rahman Hammoud , Naila Raboudi , Edriss S. Titi , Omar Knio , Ibrahim Hoteit

Ensemble-variational (EnVar) assimilation of wall-pressure measurements in direct numerical simulations of Mach 6 flow over a cone-flare is performed. The experimental data include pressure spectra and intensities from seven wall-mounted…

Fluid Dynamics · Physics 2026-05-18 Pierluigi Morra , Brett Tillman , Stuart Laurence , Tamer A. Zaki

The choice of the prior model can have a large impact on the ability to assimilate data. In standard applications of ensemble-based data assimilation, all realizations in the initial ensemble are generated from the same covariance matrix…

Computation · Statistics 2022-06-03 Dean S. Oliver

Model errors are increasingly seen as a fundamental performance limiter in both Numerical Weather Prediction and Climate Prediction simulations run with state of the art Earth system digital twins.This has motivated recent efforts aimed at…

Applications · Statistics 2021-09-22 Massimo Bonavita

Ensemble data assimilation in flood forecasting depends strongly on the density, frequency and statistics of errors associated with the observation network. This work focuses on the assimilation of 2D flood extent data, expressed in terms…

Image and Video Processing · Electrical Eng. & Systems 2023-05-24 Thanh Huy Nguyen , Sophie Ricci , Andrea Piacentini , Raquel Rodriguez Suquet , Gwendoline Blanchet , Santiago Pena Luque , Peter Kettig
‹ Prev 1 3 4 5 6 7 10 Next ›