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Related papers: Sparsity structures for Koopman operators

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This paper addresses structures of state space in quasiperiodically forced dynamical systems. We develop a theory of ergodic partition of state space in a class of measure-preserving and dissipative flows, which is a natural extension of…

Dynamical Systems · Mathematics 2020-10-01 Yoshihiko Susuki , Igor Mezić

The Koopman-von Neumann equation describes the evolution of wavefunctions associated with autonomous ordinary differential equations and can be regarded as a quantum physics-inspired formulation of classical mechanics. The main advantage…

Dynamical Systems · Mathematics 2026-04-10 Stefan Klus , Feliks Nüske , Patrick Gelß

Human interpretation of the world encompasses the use of symbols to categorize sensory inputs and compose them in a hierarchical manner. One of the long-term objectives of Computer Vision and Artificial Intelligence is to endow machines…

Computer Vision and Pattern Recognition · Computer Science 2021-10-04 Armand Comas , Sandesh Ghimire , Haolin Li , Mario Sznaier , Octavia Camps

The Koopman linearization of measure-preserving systems or topological dynamical systems on compact spaces has proven to be extremely useful. In this article we look at dynamics given by continuous semiflows on completely regular spaces…

Functional Analysis · Mathematics 2021-04-28 Bálint Farkas , Henrik Kreidler

The Koopman operator framework can be used to identify a data-driven model of a nonlinear system. Unfortunately, when the data is corrupted by noise, the identified model can be biased. Additionally, depending on the choice of lifting…

Systems and Control · Electrical Eng. & Systems 2024-09-02 Louis Lortie , James Richard Forbes

We consider the training process of a neural network as a dynamical system acting on the high-dimensional weight space. Each epoch is an application of the map induced by the optimization algorithm and the loss function. Using this induced…

Machine Learning · Computer Science 2020-06-23 Iva Manojlović , Maria Fonoberova , Ryan Mohr , Aleksandr Andrejčuk , Zlatko Drmač , Yannis Kevrekidis , Igor Mezić

Recently Koopman operator has become a promising data-driven tool to facilitate real-time control for unknown nonlinear systems. It maps nonlinear systems into equivalent linear systems in embedding space, ready for real-time linear control…

Robotics · Computer Science 2022-06-16 Haojie Shi , Max Q. -H. Meng

This paper considers the observability of nonlinear systems from a Koopman operator theoretic perspective--and in particular--the effect of symmetry on observability. We first examine an infinite-dimensional linear system (constructed using…

Systems and Control · Computer Science 2020-02-11 Afshin Mesbahi , Jingjing Bu , Mehran Mesbahi

Koopman operator theory enables linear analysis of nonlinear dynamical systems by lifting their evolution to infinite-dimensional function spaces. However, finite-dimensional approximations of Koopman and transfer (Frobenius--Perron)…

Dynamical Systems · Mathematics 2025-07-24 April Herwig , Matthew J. Colbrook , Oliver Junge , Péter Koltai , Julia Slipantschuk

We provide a framework for learning of dynamical systems rooted in the concept of representations and Koopman operators. The interplay between the two leads to the full description of systems that can be represented linearly in a finite…

Dynamical Systems · Mathematics 2020-10-13 Igor Mezic

Smoothness has long been the dominant form of parsimony in functional data analysis, to the point of occasionally being conflated with the very notion of functional data. However, many core inferential tasks depend on the inverse…

Methodology · Statistics 2026-04-21 Ulysse Naepels , Victor M. Panaretos

The Koopman operator lifts nonlinear dynamical systems into a functional space of observables, where the dynamics are linear. In this paper, we provide three different Koopman representations for hybrid systems. The first is specific to…

Dynamical Systems · Mathematics 2020-06-23 Craig Bakker , Arnab Bhattacharya , Samrat Chatterjee , Casey J. Perkins , Matthew R. Oster

Spatial temporal reconstruction of dynamical system is indeed a crucial problem with diverse applications ranging from climate modeling to numerous chaotic and physical processes. These reconstructions are based on the harmonious…

Dynamical Systems · Mathematics 2025-05-13 Nishant Panda , Himanshu Singh , J. Nathan Kutz

Transfer and Koopman operator methods offer a framework for representing complex, nonlinear dynamical systems via linear transformations, enabling a deeper understanding of the underlying dynamics. The spectra of these operators provide…

Dynamical Systems · Mathematics 2026-03-25 Gary Froyland , Kevin Kühl

Koopman and Perron-Frobenius operators for dynamical systems have been getting popular in a number of fields in science these days. Properties of the Koopman operator essentially depend on the choice of function spaces where it acts.…

Dynamical Systems · Mathematics 2024-01-29 Masahiro Ikeda , Isao Ishikawa , Corbinian Schlosser

This paper presents a methodology to achieve lower-dimensional Koopman quasi-linear representations of nonlinear system dynamics using Koopman generalized eigenfunctions. The proposed approach considers the analytically derived Koopman…

Systems and Control · Electrical Eng. & Systems 2025-10-28 Simone Martini , Margareta Stefanovic , Kimon P. Valavanis

We introduce the dynamics mode decomposition for monitoring wide-area power grid networks from sparse measurement data. The mathematical framework fuses data from multiple sensors based on multivariate statistics, providing accurate full…

Pattern Formation and Solitons · Physics 2019-06-11 J. Jorge Ramos , J. Nathan Kutz

The filtering problems are derived from a sequential minimization of a quadratic function representing a compromise between model and data. In this paper, we use the Perron-Frobenius operator in stochastic process to develop a…

Numerical Analysis · Mathematics 2023-01-10 Ningxin Liu , Lijian Jiang

This paper presents a data-driven method for constructing a Koopman linear model based on the Direct Encoding (DE) formula. The prevailing methods, Dynamic Mode Decomposition (DMD) and its extensions are based on least squares estimates…

Machine Learning · Computer Science 2023-01-18 Jerry Ng , Haruhiko Harry Asada

Transfer operators offer linear representations and global, physically meaningful features of nonlinear dynamical systems. Discovering transfer operators, such as the Koopman operator, require careful crafted dictionaries of observables,…

Robotics · Computer Science 2023-08-15 Tahiya Salam , Alice Kate Li , M. Ani Hsieh