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Imitation learning holds tremendous promise in learning policies efficiently for complex decision making problems. Current state-of-the-art algorithms often use inverse reinforcement learning (IRL), where given a set of expert…

Robotics · Computer Science 2023-02-22 Siddhant Haldar , Vaibhav Mathur , Denis Yarats , Lerrel Pinto

Recent developments in numerical weather prediction have led to the use of correlated observation error covariance (OEC) information in data assimilation and forecasting systems. However, diagnosed OEC matrices are often ill-conditioned and…

Atmospheric and Oceanic Physics · Physics 2020-06-24 Jemima M. Tabeart , Sarah L. Dance , Amos S. Lawless , Stefano Migliorini , Nancy K. Nichols , Fiona Smith , Joanne A. Waller

Four-dimensional variational data assimilation (4D-Var) on a seasonal-to-interdecadal time scale under the existence of unstable modes can be viewed as an optimization problem of synchronized, coupled chaotic systems. The problem is tackled…

Data Analysis, Statistics and Probability · Physics 2015-11-17 Nozomi Sugiura , Shuhei Masuda , Yosuke Fujii , Masafumi Kamachi , Yoichi Ishikawa , Toshiyuki Awaji

The 4D-Var method for filtering partially observed nonlinear chaotic dynamical systems consists of finding the maximum a-posteriori (MAP) estimator of the initial condition of the system given observations over a time window, and…

Methodology · Statistics 2021-01-19 Daniel Paulin , Ajay Jasra , Alexandros Beskos , Dan Crisan

We present a new iterative rotation inversion technique based on the Simultaneous Algebraic Reconstruction Technique developed for image reconstruction. We describe in detail our algorithmic implementation and compare it to the classical…

Solar and Stellar Astrophysics · Physics 2024-06-17 Sylvain G. Korzennik , Antonio Eff-Darwich

This paper introduces a novel approach to automatic ahead-of-time (AOT) parallelization and optimization of sequential Python programs for execution on distributed heterogeneous platforms. Our approach enables AOT source-to-source…

Distributed, Parallel, and Cluster Computing · Computer Science 2022-03-15 Jun Shirako , Akihiro Hayashi , Sri Raj Paul , Alexey Tumanov , Vivek Sarkar

Real-world object detection systems, such as those in autonomous driving and surveillance, must continuously learn new object categories and simultaneously adapt to changing environmental conditions. Existing approaches, Class Incremental…

Computer Vision and Pattern Recognition · Computer Science 2025-08-05 Munish Monga , Vishal Chudasama , Pankaj Wasnik , Biplab Banerjee

This paper presents a data-driven receding horizon fault estimation method for additive actuator and sensor faults in unknown linear time-invariant systems, with enhanced robustness to stochastic identification errors. State-of-the-art…

Systems and Control · Computer Science 2015-03-02 Yiming Wan , Tamas Keviczky , Michel Verhaegen , Fredrik Gustafsson

Standard gradient-based iteration algorithms for optimization, such as gradient descent and its various proximal-based extensions to nonsmooth problems, are known to converge slowly for ill-conditioned problems, sometimes requiring many…

Numerical Analysis · Mathematics 2026-03-24 G. H. M. Araújo , O. A. Krzysik , H. De Sterck

A novel data-driven method of modal analysis for complex flow dynamics, termed as reduced-order variational mode decomposition (RVMD), has been proposed, combining the idea of the separation of variables and a state-of-the-art nonstationary…

Fluid Dynamics · Physics 2022-09-27 Zi-Mo Liao , Zhiye Zhao , Liang-Bing Chen , Zhen-Hua Wan , Nan-Sheng Liu , Xi-Yun Lu

Scale-resolving flow simulations often feature several million [thousand] spatial [temporal] discrete degrees of freedom. When storing or re-using these data, e.g., to subsequently train some sort of data-based surrogate or compute…

Fluid Dynamics · Physics 2024-07-26 Niklas Kühl

Lidar data can be used to generate point clouds for the navigation of autonomous vehicles or mobile robotics platforms. Scan matching, the process of estimating the rigid transformation that best aligns two point clouds, is the basis for…

Robotics · Computer Science 2022-08-01 Matthew McDermott , Jason Rife

The focus of this paper is on stochastic variational inequalities (VI) under Markovian noise. A prominent application of our algorithmic developments is the stochastic policy evaluation problem in reinforcement learning. Prior…

Optimization and Control · Mathematics 2021-08-17 Georgios Kotsalis , Guanghui Lan , Tianjiao Li

Multimodal image matching is an important prerequisite for multisource image information fusion. Compared with the traditional matching problem, multimodal feature matching is more challenging due to the severe nonlinear radiation…

Computer Vision and Pattern Recognition · Computer Science 2023-03-02 Jiayuan Li , Pengcheng Shi , Qingwu Hu , Yongjun Zhang

Satellite observations play a critical role in numerical weather prediction where they are assimilated through an observation operator that maps model states to radiances. In the traditional Ensemble Kalman Filter, these observations are…

Atmospheric and Oceanic Physics · Physics 2026-03-24 Gian Luca Buono , Stefanie Hollborn , Roland Potthast , Jörg Schäfer , Martin Simon

The four-dimensional variational data assimilation (4D-Var) has emerged as an important methodology, widely used in numerical weather prediction, oceanographic modeling, and climate forecasting. Classical unconstrained gradient-based…

Numerical Analysis · Mathematics 2024-10-08 Bowen Li , Bin Shi

A novel method, based on the combination of data assimilation and machine learning is introduced. The new hybrid approach is designed for a two-fold scope: (i) emulating hidden, possibly chaotic, dynamics and (ii) predicting their future…

Machine Learning · Statistics 2020-07-27 Julien Brajard , Alberto Carassi , Marc Bocquet , Laurent Bertino

4D-variational data assimilation is applied to the Lorenz '63 model to introduce a new method for parameter estimation in chaotic climate models. The approach aims to optimise an Earth system model (ESM), for which no adjoint exists, by…

Atmospheric and Oceanic Physics · Physics 2025-04-18 Philip David Kennedy , Abhirup Banerjee , Armin Köhl , Detlef Stammer

This work introduces a new class of four-dimensional variational data assimilation (4D-Var) methods grounded in data-consistent inversion (DCI) theory. The methods extend classical 4D-Var by incorporating a predictability-aware…

Numerical Analysis · Mathematics 2025-11-04 Rylan Spence , Troy Butler , Clint Dawson

Recently, the progress in the radar sensing technology consisting in the miniaturization of the packages and increase in measuring precision has drawn the interest of the robotics research community. Indeed, a crucial task enabling autonomy…

Robotics · Computer Science 2026-02-05 Jan Michalczyk