Results 1 to 10 of about 19,312,029 (301)
Cyclic Nonlinear Correlation Analysis for Time Series
IEEE Access, 2022 Principal component analysis (PCA) and kernel PCA allow the decorrelation of data with respect to a basis that is found via variance maximization. However, these techniques are based on pointwise correlations.
Christopher M. A. Bonenberger +3 more
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Pythagorean fuzzy time series approach based on hybrid high-order artificial neural network for nonlinear time series forecasting [PDF]
Scientific ReportsFuzzy time series forecasting methods rely on the fuzzification of time-series observations through membership functions and the subsequent use of fuzzy-valued variables in the forecasting process.
Ozge Gundogdu, Erol Egrioglu, Eren Bas
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Stability Conditions for a Nonlinear Time Series Model
International Journal of Mathematics and Mathematical Sciences, 2023 This research aims to determine whether the proposed time series model is stable or not. To achieve this, Ozaki’s approximation method was utilized, where the nonlinear part is a function that approaches zero, similar to Ozaki’s imposed function.
Anas S. Youns, Salim M. Ahmad
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Coupling between Blood Pressure and Subarachnoid Space Width Oscillations during Slow Breathing
Entropy, 2021 The precise mechanisms connecting the cardiovascular system and the cerebrospinal fluid (CSF) are not well understood in detail. This paper investigates the couplings between the cardiac and respiratory components, as extracted from blood pressure (BP ...
Agnieszka Gruszecka +11 more
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Wavelet analysis for non-stationary, nonlinear time series [PDF]
Nonlinear Processes in Geophysics, 2016 Methods for detecting and quantifying nonlinearities in nonstationary time series are introduced and developed. In particular, higher-order wavelet analysis was applied to an ideal time series and the quasi-biennial oscillation (QBO) time series ...
J. A. Schulte
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Mathematics, 2023 Testing for complex serial dependence in economic and financial time series is a crucial task that bears many practical implications. However, the linear paradigm remains pervasive among practitioners as the autocorrelation function, because, despite its
Simone Giannerini, Greta Goracci
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Nonlinear Analysis of Financial Time Series [PDF]
Ovidius University Annals: Economic Sciences Series, 2022 One of the axioms of the modern science states that, if one can identify an exact mathematical description of a physical system, then a very detailed understanding of the system’s properties is possible.
Sorin Vlad, Mariana Vlad
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Nonlinear time series models for the North Atlantic Oscillation [PDF]
Advances in Statistical Climatology, Meteorology and Oceanography, 2020 The North Atlantic Oscillation (NAO) is the dominant mode of climate variability over the North Atlantic basin and has a significant impact on seasonal climate and surface weather conditions.
T. Önskog +3 more
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Chaotic time series. Part II. System Identification and Prediction [PDF]
Modeling, Identification and Control, 1994 This paper is the second in a series of two, and describes the current state of the art in modeling and prediction of chaotic time series. Sample data from deterministic non-linear systems may look stochastic when analysed with linear methods.
Bjørn Lillekjendlie +2 more
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Eddies: Fluid Dynamical Niches or Transporters?–A Case Study in the Western Baltic Sea
Frontiers in Marine Science, 2019 Fluid flows in the ocean have a strong impact on the growth and distribution of planktonic communities. In this case study, we applied a Lagrangian eddy detection and tracking tool and a transfer operator approach to data from a coupled hydrodynamical ...
Rahel Vortmeyer-Kley +5 more
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