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Chinese Optics Letters 2023年第4期21卷 31-36页

作者：赵宇李嘉玮张梦雷赵洋洋邹江林陈涛 Institute of Advanced Photonic Technology Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China Key Laboratory of Trans-scale Laser Manufacturing Technology(Beijing University of Technology) Ministry of EducationBeijing 100124China

The self-mixing interferometry(SMI)technique is an emerging sensing technology in microscale particle ***,due to the nature of the SMI effect raised by a microscattering particle,the signal analysis suffers from many problems compared with a macro target,such as lower signal-to-noise ratio(SNR),short transit time,and time-varying modulation ***,the particle sizing measurement resolution is much lower than the one in typical displacement *** solve these problems,in this paper,first,a theoretical model of the phase variation of a singleparticle SMI signal burst is demonstrated in *** relationship between the phase variation and the particle size is investigated,which predicts that phase observation could be another alternative for particle ***,combined with continuous wavelet transform and hilbert transform,a novel phase-unwrapping algorithm is *** algorithm can implement not only efficient individual burst extraction from the noisy raw signal,but also precise phase calculation for particle *** measurement shows good accuracy over a range from 100 nm to 6μm with our algorithm,proving that our algorithm enables a simple and reliable quantitative particle characteristics retrieval and analysis methodology for microscale particle detection in biomedical or laser manufacturing fields.

关键词： self-mixing interferometry particle detection continuous wavelet transform laser processing hilbert transform

Experimental evaluation of temperature distribution of a vapor cell using a hilbert transform procedure

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High Power Laser Science and Engineering 2016年第4期4卷 1-5页

作者： He Cai You Wang Ming Gao Wei Zhang Zhigang Jiang Juhong Han Guofei An Shunyan Wang Liangping Xue Hongyuan Wang Jie Zhou Southwest Institute of Technical Physics

A diode-pumped alkali vapor laser(DPAL) is one of the most promising candidates of the next-generation high-powered laser source. As the saturated number density of alkali vapor is highly dependent on the temperature inside a vapor cell,the temperature distribution in the cross-section of a cell will greatly affect the homogeneity of a laser medium and the output characteristics of a DPAL. In this paper, we developed an algorithm based on the regime concluding quasi-hilbert transform to evaluate the phase aberration of a wavefront when the probe beam passes through the vapor cell placed in one arm of a Mach–Zehnder interference setup. According to the theoretical algorithm, we deduced the temperature distribution of a cesium vapor cell for different heating conditions. The study is thought to be useful for development of a high-powered laser.

关键词： DPAL hilbert transform temperature distribution vapor cell

Hlder Norm Estimate for a hilbert transform in Hermitean Clifford Analysis

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Acta Mathematica Sinica,English Series 2012年第11期28卷 2289-2300页

作者： Ricardo ABREU-BLAYA Juan BORY-REYES Fred BRACKX Hennie DE SCHEPPER Frank SOMMEN Facultad de Informática y Matemática Universidad de Holguín Departamento de Matemática Universidad de Oriente Clifford Research Group Faculty of Engineering Ghent University Clifford Research Group Faculty of Sciences Ghent University

A hilbert transform for H61der continuous circulant （2 × 2） matrix functions, on the d- summable （or fractal） boundary F of a Jordan domain Ω in R2n, has recently been introduced within the framework of Hermitean Clifford analysis. The main goal of the present paper is to estimate the HSlder norm of this Hermitean hilbert transform. The expression for the upper bound of this norm is given in terms of the HSlder exponents, the diameter of F and a specific d-sum （d 〉 d） of the Whitney decomposition of Ω. The result is shown to include the case of a more standard hilbert transform for domains with left Ahlfors-David regular boundary.

关键词： Hermitean Clifford analysis hilbert transform fractal geometry

Phase Error Compensation of Three-Dimensional Reconstruction Combined with hilbert transform

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Computers, Materials & Continua 2021年第9期68卷 3121-3131页

作者： Tao Zhang Jie Shen Shaoen Wu School of Mechanical Engineering North China University of Water Conservancy and Hydroelectric PowerZhengzhou450045China Department of Computer Science Ball State UniversityMuncie47306INUSA

Nonlinear response is an important factor affecting the accuracy of three-dimensional image measurement based on the fringe structured light method.A phase compensation algorithm combined with a hilbert transform is proposed to reduce the phase error caused by the nonlinear response of a digital projector in the three-dimensional measurement system of fringe structured *** to the analysis of the influence of Gamma distortion on the phase calculation,the algorithm establishes the relationship model between phase error and harmonic coefficient,introduces phase shift to the signal,and keeps the signal amplitude constant while filtering out the DC *** phase error is converted to the transform domain,and compared with the numeric value in the space *** algorithm is combined with a spiral phase function to optimize the hilbert transform,so as to eliminate external noise,enhance the image quality,and get an accurate phase *** results show that the proposed method can effectively improve the accuracy and speed of phase *** performing phase error compensation for free-form surface objects,the phase error is reduced by about 26%,and about 27%of the image reconstruction time is saved,which further demonstrates the feasibility and effectiveness of the method.

关键词： Three-dimensional reconstruction structured light hilbert transform phase compensation

Condition Evaluation in Steel Truss Bridge with Fused hilbert transform,Spectral Kurtosis,and Bandpass Filter

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Structural Durability & Health Monitoring 2021年第2期15卷 139-165页

作者： Anshul Sharma Pardeep Kumar Hemant Kumar Vinayak uresh Kumar Walia National Institute of Technology Hamirpur177005India Entrepreneurship Development and Industrial Coordination Department National Institute of Technical Teachers Training and ResearchChandigarh160019India Himachal Pradesh Public Works Department Kangra176001India

This study is concerned with the diagnosis of discrepancies in a steel truss bridge by identifying dynamic properties from the vibration response signals of the *** vibration response signals collected at bridges under three different vehicular speeds of 10 km/hr,20 km/hr,and 30 km/hr are analyzed using statistical features such as kurtosis,magnitude of peak-to-peak,root mean square,crest factor as well as impulse factor in time domain,and Stockwell transform in the time-frequency *** considered statistical features except for kurtosis show uncertain *** Stockwell transform showed low-resolution outcomes when the presence of noise in the recorded vibration *** elimination of noise and extraction of meaningful dynamic properties from the vibration responses is done by applying a new method which comes from the fusion of hilbert transform with Spectral kurtosis and bandpass *** outcomes obtained from hilbert transform processed residual signals which are further filtered using bandpass filter show more robustness and accuracy in characterizing bridge modal frequencies from the noisy vibration *** proposed method produces a high-resolution frequency response which can unveil the joint discrepancy in the bridge structure.

关键词： Steel bridge damage detection stockwell transform hilbert transform spectral kurtosis bandpass filter

A Method for Incipient Fault Diagnosis of Roller Bearings Based on the Wavelet transform Correlation Filter and hilbert transform

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International Journal of Plant Engineering and Management 2007年第4期12卷 192-198页

作者： ZENG Qing-hu QIU Jing LIU Guan-jun College of Mechatronic Engineering and Automation National University of Defense Technology Changsha 410073 P. R. China

Noise is the biggest obstacle that makes the incipient fault diagnosis results of roller bearings uncorrected; a new method for diagnosing incipient fault of roller bearings based on the Wavelet transform Correlation Filter and hilbert transform was proposed. First, the weak fault information features are picked up from the roller bearings fault vibration signals by use of a de-noising characteristic of the Wavelet transform Correlation Filter as the preprocessing of the hilbert Envelope Analysis. Then, in order to get fault features frequency, de-noised wavelet coefficients of high scales which represent high frequency signal were analyzed by hilbert Envelope Spectrum Analysis. The simulation signals and diagnosing examples analysis results reveal that the proposed method is more effective than the method of direct wavelet coefficients-hilbert transform in de-noising and clarifying roller bearing incipient fault.

关键词： wavelet correlation Filter hilbert transform envelope spectrum fault diagnosis roller bearings

Comparative analysis of phase difference estimation methods based on hilbert transform with or without endpoint effect

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Comparative analysis of phase difference estimation methods ...

A hilbert transform Based Method for Dynamic Phase Difference Measurement

第三十九届中国控制会议

作者： Huiyue Yang YaQing Tu Yuqin Peng Army Logistics University of PLA

The hilbert transform method has its own particular superiority in phase difference estimation, but endpoint effect limits its precision when data record is short. We firstly analyze endpoint effect of hilbert transform and point out its reason is spectrum leakage. Then, an all phase hilbert transform method is proposed to solve this problem. In this method, a pretreatment is carried out at the first place that data record is recomposed with all cases of truncation been considered. In succession, hilbert transform of the pretreated data is calculated. Phase difference is estimated by triangle operation of the pretreated data and its hilbert transform. Comparative analysis of phase difference estimation methods based on hilbert transform with or without endpoint effect is carried out. Theoretical analysis, simulation and experimental results collaborate to prove the validity of the proposed method. Comparative studies demonstrate that the proposed method suppresses endpoint effect effectively and improves the precision significantly when calculational points are deficiency.

关键词： phase difference estimation hilbert transform endpoint effect all phase spectrum leakage

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A Hilbert Transform Based Method for Dynamic Phase Differenc...

Novel self-embedding holographic watermarking image encryption protection scheme

第24届中国控制与决策会议

作者： Huiyue Yang 1 , Yaqing Tu 1 , Haitao Zhang 1 , Kanghui Yang 2 1.Dept. of Information Engineering, 2.Dept. of Barracks’ Management & Environmental Engineering University of Logistical Engineering, Chongqing 401311, China

It is required in many applications to measure the phase difference of sinusoid signals with same frequency precisely and timely. And here is a method proposed for dynamic phase difference detection, which includes three procedures. After using singular value decomposition algorithm to filter the signals, the ±π / 2phase-shift function of original sinusoid is obtain by hilbert transform. And under this foundation the phase difference can be figured out by triangle transform and some simple operations. Simulation results illustrate that the proposed method can accurately estimate the rapidly-changed phase difference, while the sliding Goertzel algorithm （SGA） is applicable only when the phase difference varies slowly. The availability of the proposed method is also demonstrated by a practical application in Coriolis mass flowmeters （CMF）.

关键词： Phase Difference Measurement hilbert transform Singular Value Decomposition Coriolis Mass Flowmeter

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Chinese Physics B 2024年第5期33卷 281-290页

作者：王励年周楠润孙博曹颖鸿牟俊 School of Information Science and Engineering Dalian Polytechnic UniversityDalian 116034 China School of Electronic and Electrical Engineering Shanghai University of Engineering ScienceShanghai 201620China

For digital image transmission security and information copyright,a new holographic image self-embedding watermarking encryption scheme is ***,the plaintext is converted to the RGB three-color channel,the corresponding phase hologram is obtained by holographic technology and the watermark is self-embedded in the frequency ***,by applying the hilbert transform principle and genetic center law,a complete set of image encryption algorithms is constructed to realize the encryption of image ***,simulation results and security analysis indicate that the scheme can effectively encrypt and decrypt image information and realize the copyright protection of *** introduced scheme can provide some support for relevant theoretical research,and has practical significance.

关键词： color image encryption hilbert transform self-embedding watermark holographic technology

Design of a Multifrequency Signal Parameter Estimation Method for the Distribution Network Based on HIpST

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Energy Engineering 2024年第3期121卷 729-746页

作者： Bin Liu Shuai Liang Renjie Ding Shuguang Li Tongliao Power Supply Company State Grid East Inner Mongolia Electric Power Co.Ltd.Tongliao028000China School of Electrical Engineering Northeast Electric Power UniversityJilin132012China

The application of traditional synchronous measurement methods is limited by frequent fluctuations of electrical signals and complex frequency components in distribution ***,it is critical to find solutions to the issues of multifrequency parameter estimation and synchronous measurement estimation accuracy in the complex environment of distribution *** utilizing the multifrequency sensing capabilities of discrete Fourier transform signals and Taylor series for dynamic signal processing,a multifrequency signal estimation approach based on HT-IpDFT-STWLS(HIpST)for distribution networks is ***,by introducing the hilbert transform(HT),the influence of noise on the estimation algorithm is ***,signal frequency components are obtained on the basis of the calculated signal envelope spectrum,and the interpolated discrete Fourier transform(IpDFT)frequency coarse estimation results are used as the initial values of symmetric Taylor weighted least squares(STWLS)to achieve high-precision parameter estimation under the dynamic changes of the signal,and the method increases the number of discrete ***,the accuracy of this proposed method is verified by simulation *** show that this proposed method can accurately achieve the parameter estimation of multifrequency signals in distribution *** approach provides a solution for the application of phasor measurement units in distribution networks.

关键词： Discrete fourier transform taylor series hilbert transform multifrequency signal parameter estimation