Results 21 to 30 of about 1,082,543 (312)
Model-Free Geometric Fault Detection and Isolation for Nonlinear Systems Using Koopman Operator
IEEE Access, 2022 This paper presents a model-free fault detection and isolation (FDI) method for nonlinear dynamical systems using Koopman operator theory and linear geometric technique.
Mohammadhosein Bakhtiaridoust +3 more
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Deep Koopman operators for causal discovery
Communications PhysicsCausal discovery aims to identify cause-effect mechanisms for better scientific understanding, explainable decision-making, and more accurate modeling.
Juan Nathaniel +6 more
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Glocal Hypergradient Estimation with Koopman Operator [PDF]
Gradient-based hyperparameter optimization methods update hyperparameters using hypergradients, gradients of a meta criterion with respect to hyperparameters. Previous research used two distinct update strategies: optimizing hyperparameters using global hypergradients obtained after completing model training or local hypergradients derived after every ...
Ryuichiro Hataya, Yoshinobu Kawahara
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Koopman Operators and the $3x+1$-Dynamical System [PDF]
SIAM Journal on Applied Dynamical Systems, 2021 The $3x+1$-problem (or Collatz problem) is a notorious conjecture in arithmetic. It can be viewed as iterating a map and, therefore, it is a dynamical system on the discrete space $\mathbb{N}$ of natural numbers. The emerging dynamical system is studied in the present work with methods from the theory of Koopman operators and $C^*$-algebras.
John Leventides, Costas Poulios
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Measurement + Control, 2022 Omnidirectional mobile manipulators (OMMs) have been widely used due to their high mobility and operating flexibility. However, since OMMs are complex nonlinear systems with uncertainties, the dynamic modeling and control are always challenging problems.
Xuehong Zhu +3 more
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Symplectic Geometry of the Koopman Operator [PDF]
Doklady Mathematics, 2021 Abstract We consider the Koopman operator generated by an invertible transformation of a space with a finite countably additive measure. If the square of this transformation is ergodic, then the orthogonal Koopman operator is a symplectic transformation on the real Hilbert space of square summable functions with zero ...
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Energy and AI, 2023 In this study, a novel application of the Koopman operator for control-oriented modeling of proton exchange membrane fuel cell (PEMFC) stacks is proposed. The primary contributions of this paper are: (1) the design of Koopman-based models for a fuel cell
Da Huo, Carrie M. Hall
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Renormalization group as a Koopman operator [PDF]
Physical Review E, 2020 Koopman operator theory is shown to be directly related to the renormalization group. This observation allows us, with no assumption of translational invariance, to compute the critical exponents $ $ and $ $, as well as ratios of critical exponents, of classical spin systems from single observables alone.
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A quantitative analysis of Koopman operator methods for system identification and predictions
Comptes Rendus. Mécanique, 2022 We give convergence and cost estimates for a data-driven system identification method: given an unknown dynamical system, the aim is to recover its vector field and its flow from trajectory data.
Zhang, Christophe, Zuazua, Enrique
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Diffeomorphically Learning Stable Koopman Operators
IEEE Control Systems Letters, 2022 Comment: Revised version submitted to IEEE Control Systems Letters (L-CSS) with substantially revised exposition, evaluation and proof of Lemma 2 (previously Lemma 8)
Petar Bevanda +5 more
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