Results 41 to 50 of about 16,012 (278)
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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Journal of Low Frequency Noise, Vibration and Active Control, 2018 Civil engineering structures in essence belong to time-varying and nonlinear structures and the resultant dynamic responses are usually nonstationary signals. A new method is proposed to extract instantaneous frequency of such nonstationary signals.
Jing-Liang Liu +4 more
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Infrastructures, 2022 Even though prefabricated steel Bailey bridges have been used for more than 80 years, limited studies of their structural features have been conducted, most of which do not consider their response in operational conditions.
Vasileios D. Papavasileiou +3 more
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Extended Nodal Admittance Matrix Based Stability Analysis of HVDC Connected AC Grids
IEEE Access, 2022 Motivated by emerging HVDC oscillation issues resulted from the interaction with AC grids, impedance-based stability analysis has become an attractive approach in the de-risking studies due to the capability of black-box modelling and clear physical ...
Yonggang Zhang +3 more
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$L^\infty$-error bounds for approximations of the Koopman operator by kernel extended dynamic mode decomposition [PDF]
Extended dynamic mode decomposition (EDMD) is a well-established method to generate a data-driven approximation of the Koopman operator for analysis and prediction of nonlinear dynamical systems. Recently, kernel EDMD (kEDMD) has gained popularity due to its ability to resolve the challenging task of choosing a suitable dictionary by using the kernel's
Frederik Köhne +4 more
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An Improved Parallel MDBN With AVMD for Nonlinear System Modeling
IEEE Access, 2020 Nonlinear system modeling using Deep Belief Network (DBN) is currently a research hotspot. However, the training process of DBN needs large amount of data to guarantee accuracy, and the traditional DBN may not meet the requirement of high-precision ...
Qibing Jin +4 more
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Mathematics, 2021 In this paper, we introduce a model-free algorithm, robust mode analysis (RMA), to extract primary constituents in a fluid or reacting flow directly from high-frequency, high-resolution experimental data.
Gemunu H. Gunaratne, Sukesh Roy
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A concise introduction to Koopman operator theory and the Extended Dynamic Mode Decomposition [PDF]
13 pages, subject introduction ...
Christophe Patyn, Geert Deconinck
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International Journal of Automotive Engineering, 2017 In this research, we conduct unsteady CFD to investigate the effect of engine bay flow on the steady and unsteady aerodynamics of the extended DrivAer model reproducing engine bay flow.
Daiki Matsumoto +2 more
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Spectral Properties of Effective Dynamics from Conditional Expectations
Entropy, 2021 The reduction of high-dimensional systems to effective models on a smaller set of variables is an essential task in many areas of science. For stochastic dynamics governed by diffusion processes, a general procedure to find effective equations is the ...
Feliks Nüske +3 more
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