Results 21 to 30 of about 75,598 (299)
Application of Local Histogram Clipping Equalization Image Enhancement in Bearing Fault Diagnosis
IEEE Access, 2022 Aiming at the problem that the time-frequency image of bearing fault characteristics is relatively weak and difficult to identify. This paper presents a time-frequency analysis method of local maximum synchrosqueezing transform based on image enhancement.
Zhiqiang Zeng +3 more
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An Improved Multi-Ridge Extraction Method Based on Differential Synchro-Squeezing Wavelet Transform
IEEE Access, 2021 It is very important to accurately extract the instantaneous frequency (IF) of complex non-stationary signals, so the signal processing methods based on IF are widely used in engineering.
Yanfeng Li +3 more
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Bivariate Instantaneous Frequency and Bandwidth [PDF]
IEEE Transactions on Signal Processing, 2010 The generalizations of instantaneous frequency and instantaneous bandwidth to a bivariate signal are derived. These are uniquely defined whether the signal is represented as a pair of real-valued signals, or as one analytic and one anti-analytic signal.
Jonathan M. Lilly, Sofia C. Olhede
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Window Functions With Minimum-Sidelobe Derivatives for Computing Instantaneous Frequency
IEEE Access, 2022 In the field of nonstationary signal analysis and processing, the short-time Fourier transform (STFT) is frequently used to convert signals into the time-frequency domain.
Tsubasa Kusano +2 more
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An iterative method for instantaneous frequency estimation
, 2021 In this paper, we propose an iterative method to estimate the instantaneous frequency of a signal based on the discrete evolutionary transform (DET). The DET provides a representation for non-stationary signals and a time-frequency kernel that permits us
Yalcin, M, Akan, A, Chaparro, LF
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Applied Sciences, 2022 The rub-impact fault, which occurs in the aeroengine, can cause frequency modulation (FM) in its vibration signal. Oscillated instantaneous frequency (IF) is a phenomenon of such a modulation mode, which carries critical fault information from the ...
Peng Zhang +7 more
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Using Differential Geometry to Revisit the Paradoxes of the Instantaneous Frequency
IEEE Open Access Journal of Power and Energy, 2022 This paper proposes a general framework to interpret the concept of Instantaneous Frequency (IF) in three-phase systems. The paper first recalls the conventional frequency-domain analysis based on the Fourier transform as well as the definition of IF ...
Federico Milano +4 more
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Machines, 2022 The vibration signal from the rotatory machinery condition monitoring under time-varying speed is usually amplitude-modulated (AM) and frequency-modulated (FM).
Yuexin Huang +4 more
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Open Geosciences, 2020 The reported occurrence of Albian- and Cenomanian-aged braided fluvio-deltaic channels in the Orange Basin, South Africa, opens a window of exploration activities to characterize these channels as they are renowned to form some of the world’s giant oil ...
Samakinde Chris Adesola +2 more
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Definition of instantaneous frequency on real signals
, 2000 This paper introduces a definition of the instantaneous frequency (IF) on real signals. Basically the definition ωt = xt/√1 - x2t avoids some pitfalls associated with the corresponding definition on analytic signals.
Saliu, Sokol,
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