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Acta Seismologica Sinica(English Edition) 2005年第1期18卷 34-42,124页

作者：李杰刘希强李红毛玉华郑树田 Earthquake Administration of Shandong Province Taian Seismological Fiducial Station of Shandong Province Earthquake Administration of Anqiu

wavelet transform method is applied to measure time-frequency distribution characteristics of digital deformation data and noise. Based on the characteristics of primary modulus and stochastic white noise discrimination factor of wavelet decomposition, we analyze the variation rule of normal background and noise data from Shandong digital deformation observation data. The research results indicate that: a) 1/4 daily wave, semi-diurnal tide wave, daily wave and half lunar wave and so on quasi-periodic signal exist in the detail decomposing signal of wavelet when scale are equal to 2, 3 and 4; b) The amplitude of detail decomposing signal is the biggest when scale is equal to 3; c) The detail decomposing signal contains mainly noise corresponding to scale 1 and 5, respectively; d) We may trace the abnormal precursory which is related to earthquake by analyzing non-earthquake wavelet decomposing signal whose scale is specified from digital deformation observation data.

关键词： wavelet transform digital deformation observation data separation method between signal and noise discrimination of earthquake precursory

Detection of shallow underground fissures by timefrequency analysis of Rayleigh waves based on wavelet transform

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Applied Geophysics 2020年第2期17卷 233-242,315页

作者： Shao Guang-zhou Du Ting College of Geological Engineering and Geomatics Chang’an UniversityXi’an 710054China

Ground fi ssure is a geological hazard that poses a great threat to human life and,property and the ***,it is necessary to detect shallow underground fi ssures eff *** this paper,a time-frequency analysis of Rayleigh waves based on the wavelet transform is proposed to detect shallow underground fi *** arrival time of the directed Rayleigh waves and the diff racted Rayleigh waves from the underground fi ssure is extracted from the time-frequency spectrum of any two ***,the locations of the underground fissures are calculated according to the time difference *** sets of fracture models and one set of fi eld data were used to test the eff ectiveness of the wavelet transform of Rayleigh ***,the detection results of the actual data are compared with that of the high-density electrical method to further prove its detection eff *** fi eld investigation shows that using the wavelet transform of Rayleigh waves to detect shallow underground fi ssures is feasible and eff ective.

关键词： Underground fi ssure Rayleigh wave wavelet transform

Gravity compression forward modeling and multiscale inversion based on wavelet transform

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Applied Geophysics 2018年第2期15卷 342-352,365页

作者： Sun Si-Yuan Yin Chang-Chun Gao Xiu-He Liu Yun-He Ren Xiu-Yan College of GeoExploration Science and Technology Jilin University Changchun 130026 China

The main problems in three-dimensional gravity inversion are the non-uniqueness of the solutions and the high computational cost of large data sets. To minimize the high computational cost, we propose a new sorting method to reduce fluctuations and the high frequency of the sensitivity matrix prior to applying the wavelet transform. Consequently, the sparsity and compression ratio of the sensitivity matrix are improved as well as the accuracy of the forward modeling. Furthermore, memory storage requirements are reduced and the forward modeling is accelerated compared with uncompressed forward modeling. The forward modeling results suggest that the compression ratio of the sensitivity matrix can be more than 300. Furthermore, multiscale inversion based on the wavelet transform is applied to gravity inversion. By decomposing the gravity inversion into subproblems of different scales, the non-uniqueness and stability of the gravity inversion are improved as multiscale data are considered. Finally, we applied conventional focusing inversion and multiscale inversion on simulated and measured data to demonstrate the effectiveness of the proposed gravity inversion method.

关键词： wavelet transform matrix compression multiscale inversion gravity forwardmodeling

ECG Classification Using Deep CNN Improved by wavelet transform

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Computers, Materials & Continua 2020年第9期64卷 1615-1628页

作者： Yunxiang Zhao Jinyong Cheng Ping Zhang Xueping Peng School of Computer Science and Technology Qilu University of Technology(Shandong Academy of Sciences)Jinan250353China Centre of Artificial Intelligence University of Technology SydneySydneyNSW 2006Australia

Atrial fibrillation is the most common persistent form of arrhythmia.A method based on wavelet transform combined with deep convolutional neural network is applied for automatic classification of *** the ECG signal is easily inferred,the ECG signal is decomposed into 9 kinds of subsignals with different frequency scales by wavelet function,and then wavelet reconstruction is carried out after segmented filtering to eliminate the influence of noise.A 24-layer convolution neural network is used to extract the hierarchical features by convolution kernels of different sizes,and finally the softmax classifier is used to classify *** paper applies this method of the ECG data set provided by the 2017 PhysioNet/CINC *** cross validation,this method can obtain 87.1%accuracy and the F1 score is 86.46%.Compared with the existing classification method,our proposed algorithm has higher accuracy and generalization ability for ECG signal data classification.

关键词： Atrial fibrillation wavelet transform deep CNN

APPLICATION OF wavelet transform IN STRUCTURAL OPTIMIZATION

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Chinese Journal of Mechanical Engineering 2001年第3期14卷 231-236页

作者： Lin Hui,Zhang Youyun (Theory of Lubrication and Bearing Institute ,Xi’ an Jiaotong University) 西安交通大学轴承研究所陕西

It is very common in structural optimization that the optima lie at or in the vicinities of the singular points of feasible domain. Therefore it is very reasonable to introduce wavelet transform that is advantageous in singularity detection. The principle and algorithm of the application of wavelet transform in structural optimization are discussed The feasibility is demonstrated by some typical examples.

关键词： wavelet transform Structural optimization Singularity

Multi-Time Scale Analysis of Runoff at the Yangtze Estuary Based on the Morlet wavelet transform Method

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Journal of Mountain Science 2014年第6期11卷 1499-1506页

作者： KUANG Cui-ping SU Ping GU Jie CHEN Wu-jun ZHANG Jian-le ZHANG Wan-lei ZHANG Yong-feng Department of Hydraulic Engineering College of Civil Engineering Tongji University College of Marine Sciences Shanghai Ocean University Marine Environmental Monitoring Center of Hebei Province

Runoff series of the Yangtze River presents an intricate variation tendency under the reinforced influence of human *** Morlet wavelet transform method has been applied to analyze the annual runoff data from 1950 to 2011 at the Yangtze River *** can clearly reveal the multi-time scales structure,break point,change and distribution of periodic variation in the different time scales of the runoff *** main conclusions are that:1) Repeated periodic oscillations accompanied by an extremely large fluctuation are presented in the runoff series with an obvious difference between wet and dry years,and the major periods of the time series are about 3,8,16 and 23 years *** them,the presented maximum periodic oscillation is 23 years scale.2) In the 23-year time scale,the wet periods are 1950-1958,1969-1980 and 1992-2003,and the dry periods are 1959-1968,1981-1991 and 2004-2011.3) It can be predicted from the view of long time scales that the low annual runoff will likely occur in the near future.

关键词： Datong station wavelet transform Runoff series Periodic characteristics

Fourier Self-deconvolution Using Approximation Obtained from Frequency Domain wavelet transform as a Linear Function

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Chinese Chemical Letters 2006年第3期17卷 380-382页

作者： Yuan Zhen ZHOU Jian Bin ZHENG Institute of Analytical Science/Shaanxi Provincial Key Lab of Electroanalytical Chemistry Northwest University Xi＇an 710069

A new method of resolving overlapped peak, Fourier self-deconvolution （FSD） using approximation CN obtained from frequency domain wavelet transform of F（ω） yielded by Fourier transform of overlapped peak signals f（t） as the linear function, was presented in this paper. Compared with classical FSD, the new method exhibits excellent resolution for different overlapped peak signals such as HPLC signals, and have some characteristics such as an extensive applicability for any overlapped peak shape signals and a simple operation because of no selection procedure of the linear function. Its excellent resolution for those different overlapped peak signals is mainly because F（ω） obtained from Fourier transform of f（t） and CN obtained from wavelet transform of F（ω） have the similar linearity and peak width. The effect of those fake peaks can be eliminated by the algorithm proposed by authors. This method has good potential in the process of different overlapped peak signals.

关键词： Fourier deconvolution wavelet transform signal processing HPLC signal

A New Shape-Coding Algorithm by Using wavelet transform

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Journal of Systems Engineering and Electronics 2003年第2期14卷 69-73页

作者： Shi Xuli & Zhang Zhaoyang Communication School, Shanghai University, Shanghai 200072, P. R. China Communication School Shanghai University Shanghai 200072 P. R. China

In this paper, we propose a new shape-coding algorithm called wavelet-based shape coding (WBSC). Performing wavelet transform on the orientation of original planar curve gives the corners called corner-1 points and end of arcs that belong to the original curve. Each arc is represented by a broken line and the corners called corner-2 points of the broken line are extracted. A polygonal approximation of a contour is an ordered list of corner-1 points, ends of arcs and corner-2 points which are extracted by using the above algorithm. All of the points are called polygonal vertices which will be compressed by our adaptive arithmetic encoding. Experimental results show that our method reduces code bits by about 26% compared with the context-based arithmetic encoding (CAE) of MPEG-4, and the subjective quality of the reconstructed shape is better than that of CAE at the same Dn.

关键词： wavelet transform Shape coding WBSC MPEG-4 CAE.

Quantum Mechanics Version of wavelet transform Studied by Virtue of IWOPTechnique

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Communications in Theoretical Physics 2004年第5期41卷 681-684页

作者： FANHong-Yi LǖJian-Feng DepartmentofPhysics ShanghaiJiaoTongUniversityShanghai200030China

Using the technique of integral within an ordered product (IWOP) of operators we show that the wavelet transform can be recasted to a matrix element of squeezing-displacing operator between the mother wavelet state vector and the state vector to be transformed in the context of quantum mechanics. In this way many quantum optical states'wavelet transform can be easily derived.

关键词： wavelet transform IWOP technique squeezing-displacing operator

SIGNAL FEATURE EXTRACTION BASED UPON INDEPENDENT COMPONENT ANALYSIS AND wavelet transform

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Chinese Journal of Mechanical Engineering 2005年第1期18卷 123-126页

作者： JiZhong JinTao QinShuren CollegeofMechanicalEngineering ChongqingUniversityChongqing400030China

It is an important precondition for machine fault diagnosis that vibrationsignal can be extracted effectively. Based on the characteristic of noise interfused during thecourse of sampling vibration signal, independent component analysis (ICA) method is combined withwavelet to de-noise. Firstly, The sampled signal can be separated with ICA, then the function offrequency band chosen with multi-resolution wavelet transform can be used to judge whether thestochastic disturbance singular signal is interfused. By these ways, the vibration signals can beextracted effectively, which provides favorable condition for subsequent feature detection ofvibration signal and fault diagnosis.

关键词： Independent component analysis (ICA) wavelet transform De-noising Faultdiagnosis Feature extraction