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Unsupervised Domain Adaptation for Regression (UDAR) aims to adapt models from a labeled source domain to an unlabeled target domain for regression tasks. Traditional feature alignment methods, successful in classification, often prove…

Computer Vision and Pattern Recognition · Computer Science 2024-11-22 Ismail Nejjar , Gaetan Frusque , Florent Forest , Olga Fink

In this work, we aim at studying ensemble based optimal control strategies for data assimilation. Such formulation nicely combines the ingredients of ensemble Kalman filters and variational data assimilation (4DVar). In the same way as…

Mathematical Physics · Physics 2014-01-17 Yin Yang , Cordelia Robinson , Dominique Heitz , Etienne Mémin

Unmanned aerial vehicle-aided communication (UAB-BS) is a promising solution to establish rapid wireless connectivity in sudden/temporary crowded events because of its more flexibility and mobility features than conventional ground base…

Networking and Internet Architecture · Computer Science 2026-01-27 Chuan-Chi Lai , Bhola , Ang-Hsun Tsai , Li-Chun Wang

Dynamic downscaling typically involves using numerical weather prediction (NWP) solvers to refine coarse data to higher spatial resolutions. Data-driven models such as FourCastNet have emerged as a promising alternative to the traditional…

Atmospheric and Oceanic Physics · Physics 2025-03-05 Philip Dinenis , Vishwas Rao , Mihai Anitescu

Data-driven prediction and physics-agnostic machine-learning methods have attracted increased interest in recent years achieving forecast horizons going well beyond those to be expected for chaotic dynamical systems. In a separate strand of…

Data Analysis, Statistics and Probability · Physics 2021-05-19 Georg A. Gottwald , Sebastian Reich

We explore the potential of Data-Assimilation (DA) within the multi-scale framework of a shell model of turbulence, with a focus on the Ensemble Kalman Filter (EnKF). The central objective is to understand how measuring mesoscales (i.e.,…

Fluid Dynamics · Physics 2026-01-15 Francesco Fossella , Luca Biferale , Alberto Carrassi , Massimo Cencini , Vikrant Gupta

Variational data assimilation estimates the dynamical system states by minimizing a cost function that fits the numerical models with the observational data. Although four-dimensional variational assimilation (4D-Var) is widely used, it…

Machine Learning · Computer Science 2025-06-16 Yiming Yang , Xiaoyuan Cheng , Daniel Giles , Sibo Cheng , Yi He , Xiao Xue , Boli Chen , Yukun Hu

The inconsistency issue in the Visual-Inertial Navigation System (VINS) is a long-standing and fundamental challenge. While existing studies primarily attribute the inconsistency to observability mismatch, these analyses are often based on…

Robotics · Computer Science 2025-11-25 Chungeng Tian , Fenghua He , Ning Hao

A challenge arising from the local Bayesian assimilation of data in an atmospheric flow simulation is the imbalances it may introduce. Acoustic fast-mode imbalances of the order of the slower dynamics can be negated by employing a blended…

Numerical Analysis · Mathematics 2024-03-11 Ray Chew , Tommaso Benacchio , Gottfried Hastermann , Rupert Klein

In this paper, a novel design scheme is introduced to solve the optimal control problem for nonlinear systems with unsymmetrical and state-dependent input constraints. By introducing an initial stabilizing control policy as the baseline of…

Systems and Control · Electrical Eng. & Systems 2022-11-18 Yangguang Yu , Xiangke Wang , Zhiyong Sun , Lincheng Shen

Data assimilation (DA) aims at forecasting the state of a dynamical system by combining a mathematical representation of the system with noisy observations taking into account their uncertainties. State of the art methods are based on the…

Machine Learning · Computer Science 2023-05-26 Pierre Boudier , Anthony Fillion , Serge Gratton , Selime Gürol , Sixin Zhang

Ensemble data assimilation methods such as the Ensemble Kalman Filter (EnKF) are a key component of probabilistic weather forecasting. They represent the uncertainty in the initial conditions by an ensemble which incorporates information…

Applications · Statistics 2018-10-17 Sylvain Robert , Daniel Leuenberger , Hans R. Künsch

Accurate modeling and prediction of complex physical systems often rely on data assimilation techniques to correct errors inherent in model simulations. Traditional methods like the Ensemble Kalman Filter (EnKF) and its variants as well as…

Machine Learning · Computer Science 2024-09-12 Phillip Si , Peng Chen

Variational data assimilation optimizes for an initial state of a dynamical system such that its evolution fits observational data. The physical model can subsequently be evolved into the future to make predictions. This principle is a…

Machine Learning · Computer Science 2021-05-21 Thomas Frerix , Dmitrii Kochkov , Jamie A. Smith , Daniel Cremers , Michael P. Brenner , Stephan Hoyer

We introduce a data assimilation strategy aimed at accurately capturing key non-Gaussian structures in probability distributions using a small ensemble size. A major challenge in statistical forecasting of nonlinearly coupled multiscale…

Numerical Analysis · Mathematics 2025-04-01 Di Qi , Jian-Guo Liu

We present a new adaptive particle-based data assimilation scheme for cryospheric applications that leverages promising developments in importance sampling. The proposed approach seeks to combine some of the advantages of two widely used…

Data assimilation of atmospheric observations traditionally relies on variational and Kalman filter methods. Here, an alternative neural-network data assimilation (NNDA) with variational autoencoder (VAE) is proposed. The three-dimensional…

Atmospheric and Oceanic Physics · Physics 2024-04-29 Boštjan Melinc , Žiga Zaplotnik

Introduction of renewable generation leads to significant reduction of inertia in power system, which deteriorates the quality of frequency control. This paper suggests a new control scheme utilizing controllable load to deal with low…

Systems and Control · Computer Science 2018-11-30 Oleg O. Khamisov , Janusz W. Bialek , Anatoly Dymarsky

The use of data assimilation for the merging of observed data with dynamical models is becoming standard in modern physics. If a parametric model is known, methods such as Kalman filtering have been developed for this purpose. If no model…

Data Analysis, Statistics and Probability · Physics 2018-01-17 Franz Hamilton , Tyrus Berry , Timothy Sauer

Selecting safe landing sites in non-cooperative environments is a key step towards the full autonomy of UAVs. However, the existing methods have the common problems of poor generalization ability and robustness. Their performance in unknown…

Robotics · Computer Science 2020-11-30 Lyujie Chen , Xiaming Yuan , Yao Xiao , Yiding Zhang , Jihong Zhu