The scalographic pattern of Morlet continuous wavelet transform can differentiate bileaflet valve function

2018 ◽  
Vol 21 (3) ◽  
pp. 308-316
Author(s):  
Hiroshi Sugiki ◽  
Kenji Sugiki
Keyword(s):  
Wavelet Transform ◽  
Continuous Wavelet Transform ◽  
Continuous Wavelet ◽  
Morlet Continuous Wavelet Transform ◽  
Valve Function ◽  
Bileaflet Valve

Relative acoustic impedance from wavelet transform

2014 ◽  
Vol 2 (1) ◽  
pp. SA107-SA118 ◽  
Author(s):  
Marcílio Castro de Matos ◽  
Rodrigo Penna ◽  
Paulo Johann ◽  
Kurt Marfurt
Keyword(s):  
Wavelet Transform ◽  
Continuous Wavelet Transform ◽  
Seismic Data ◽  
Acoustic Impedance ◽  
Real Data ◽  
Velocity Model ◽  
Continuous Wavelet ◽  
Reconstruction Process ◽  
Seismic Wavelet ◽  
Morlet Continuous Wavelet Transform

Most deconvolution algorithms try to transform the seismic wavelet into spikes by designing inverse filters that remove an estimated seismic wavelet from seismic data. We assume that seismic trace subtle discontinuities are associated with acoustic impedance contrasts and can be characterized by wavelet transform spectral ridges, also called modulus maxima lines (WTMML), allowing us to improve seismic resolution by using the wavelet transform. Specifically, we apply the complex Morlet continuous wavelet transform (CWT) to each seismic trace and compute the WTMMLs. Then, we reconstruct the seismic trace with the inverse continuous wavelet transform from the computed WTMMLs with a broader band complex Morlet wavelet than that used in the forward CWT. Because the reconstruction process preserves amplitude and phase along different scales, or frequencies, the result looks like a deconvolution method. Considering this high-resolution seismic representation as a reflectivity approximation, we estimate the relative acoustic impedance (RAI) by filtering and trace integrating it. Conventional deconvolution algorithms assume the seismic wavelet to be stochastic, while the CWT is implicitly time varying such that it can be applied to both depth and time-domain data. Using synthetic and real seismic data, we evaluated the effectiveness of the methodology on detecting seismic events associated with acoustic impedance changes. In the real data examples, time and in-depth RAI results, show good correlation with real P-impedance band-pass data computed using more rigorous commercial inversion software packages that require well logs and low-frequency velocity model information.

scholarly journals Fringe pattern analysis using a one-dimensional modified Morlet continuous wavelet transform

2008 ◽  
Author(s):  
Abdulbasit Z. Abid ◽  
Munther A. Gdeisat ◽  
David R. Burton ◽  
Michael J. Lalor ◽  
Hussein S. Abdul-Rahman ◽  
...  
Keyword(s):  
Wavelet Transform ◽  
Continuous Wavelet Transform ◽  
Fringe Pattern ◽  
Pattern Analysis ◽  
Continuous Wavelet ◽  
One Dimensional ◽  
Morlet Continuous Wavelet Transform ◽  
Fringe Pattern Analysis

Pressure pulsation investigation in an electrical submersible pump based on Morlet continuous wavelet transform

2021 ◽  
pp. 095440622110000
Author(s):  
Yang Yang ◽  
Ling Zhou ◽  
Yong Han ◽  
Jianwei Hang ◽  
Wanning Lv ◽  
...  
Keyword(s):  
Wavelet Transform ◽  
Continuous Wavelet Transform ◽  
Pressure Pulsation ◽  
Low Frequency ◽  
Numerical Calculations ◽  
Continuous Wavelet ◽  
Pressure Pulsations ◽  
Frequency Signal ◽  
Multi Stage ◽  
Morlet Continuous Wavelet Transform

Electrical Submersible Pumps (ESP) are one of the most reliable and efficient ways to lift oil or water from the ground or deep-sea to the surface. How to reduce the pressure pulsation and increase reliability is a challenging issue in the ESP design processes. In this study, a typical three-stage ESP model was selected as the research object. Based on numerical calculations and validation tests, the flow-field distribution mechanism within the dynamic and static interference zones of multi-stage ESP was investigated. Meanwhile, the inter-stage variability of pressure pulsation characteristics within the main hydraulic components was explored by Morlet continuous wavelet transform. The results showed that the numerical predicted performance has an excellent agreement with the experimental results, which confirms the accuracy of the numerical calculations. The time-domain characteristics of pressure pulsation at each monitoring location within the ESP showed high disorder due to the inter-stage propagation and coupling of the pressure pulsations. The low-frequency signal in the pressure pulsation signal had not only a cascading superposition of intensity, but also a significant phase difference. It was found that the main form of propagation between pulsating signal levels is the low-frequency signal. This work may facilitate the reduction or control of the pressure pulsations and thus improve the operation stability of ESP.

The continuous wavelet transform with rotations

2005 ◽  
Vol 4 (1) ◽  
pp. 45-55
Author(s):  
Jaime Navarro ◽  
Miguel Angel Alvarez
Keyword(s):  
Wavelet Transform ◽  
Continuous Wavelet Transform ◽  
Continuous Wavelet
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