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NEW METHOD FOR WEAK FAULT FEATURE EXTRACTION BASED ON SECOND GENERATION WAVELET TRANSFORM AND ITS APPLICATION 被引量:12
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作者 DuanChendong HeZhengjia JiangHongkai 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第4期543-547,共5页
A new time-domain analysis method that uses second generation wavelettransform (SGWT) for weak fault feature extraction is proposed. To extract incipient fault feature,a biorthogonal wavelet with the characteristics o... A new time-domain analysis method that uses second generation wavelettransform (SGWT) for weak fault feature extraction is proposed. To extract incipient fault feature,a biorthogonal wavelet with the characteristics of impact is constructed by using SGWT. Processingdetail signal of SGWT with a sliding window devised on the basis of rotating operation cycle, andextracting modulus maximum from each window, fault features in time-domain are highlighted. To makefurther analysis on the reason of the fault, wavelet package transform based on SGWT is used toprocess vibration data again. Calculating the energy of each frequency-band, the energy distributionfeatures of the signal are attained. Then taking account of the fault features and the energydistribution, the reason of the fault is worked out. An early impact-rub fault caused by axismisalignment and rotor imbalance is successfully detected by using this method in an oil refinery. 展开更多
关键词 second generation wavelet transform (sgwt) wavelet package transform MISALIGNMENT IMBALANCE Impact-rub
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Adaptive Wavelets Based on Second Generation Wavelet Transform and Their Applications to Trend Analysis and Prediction
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作者 DUANChen-dong JIANGHong-kai HEZheng-jia 《International Journal of Plant Engineering and Management》 2004年第3期170-176,共7页
In order to make trend analysis and prediction to acquisition data in amechanical equipment condition monitoring system, a new method of trend feature extraction andprediction of acquisition data is proposed which con... In order to make trend analysis and prediction to acquisition data in amechanical equipment condition monitoring system, a new method of trend feature extraction andprediction of acquisition data is proposed which constructs an adaptive wavelet on the acquisitiondata by means of second generation wavelet transform ( SGWT), Firstly, taking the vanishing momentnumber of the predictor as a constraint, the linear predictor and updater are designed according tothe acquisition data by using symmetrical interpolating scheme. Then the trend of the data isobtained through doing SGWT decomposition , threshold processing and SGWT reconstruction. Secondly,under the constraint of the vanishing moment number of the predictor, another predictor based on theacquisition data is devised to predict the future trend of the data using a non-symmetricalinterpolating scheme, A one-step prediction algorithm is presented to predict the future evolutiontrend with historical data. The proposed method obtained a desirable effect in peak-to-peak valuetrend analysis for a machine set in an oil refinery. 展开更多
关键词 second generation wavelet transform ( SCWT) PREDICTOR updater trendanalysis trend prediction
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SGWT在爆破振动信号信噪分离中的应用研究 被引量:10
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作者 谢全民 龙源 +2 位作者 钟明寿 陆凡东 毛益明 《振动与冲击》 EI CSCD 北大核心 2012年第1期24-28,43,共6页
为提高测试信号分析效率和质量,引入二代小波变换并用于爆破振动信号信噪分离。采用提升db小波以及根据提升算法构造的插值细分小波,进行爆破振动信号的分解-阈值去噪-重构,取得了满意的效果。通过比较4个不同提升小波的去噪质量和效率... 为提高测试信号分析效率和质量,引入二代小波变换并用于爆破振动信号信噪分离。采用提升db小波以及根据提升算法构造的插值细分小波,进行爆破振动信号的分解-阈值去噪-重构,取得了满意的效果。通过比较4个不同提升小波的去噪质量和效率,提出了适用于爆破振动信号分析的提升小波选取办法,为将SGWT引入到爆破振动信号分析研究领域,实现爆破振动特征的快速提取提供了参考。 展开更多
关键词 爆破振动 信噪分离 二代小波变换 提升算法 插值细分
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Feature Extraction of Bearing Vibration Signals Using Second Generation Wavelet and Spline-Based Local Mean Decomposition 被引量:5
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作者 文成玉 董良 金欣 《Journal of Shanghai Jiaotong university(Science)》 EI 2015年第1期56-60,共5页
In order to extract the fault feature frequency of weak bearing signals,we put forward a local mean decomposition(LMD)method combining with the second generation wavelet transform.After performing the second generatio... In order to extract the fault feature frequency of weak bearing signals,we put forward a local mean decomposition(LMD)method combining with the second generation wavelet transform.After performing the second generation wavelet denoising,the spline-based LMD is used to decompose the high-frequency detail signals of the second generation wavelet signals into a number of production functions(PFs).Power spectrum analysis is applied to the PFs to detect bearing fault information and identify the fault patterns.Application in inner and outer race fault diagnosis of rolling bearing shows that the method can extract the vibration features of rolling bearing fault.This method is suitable for extracting the fault characteristics of the weak fault signals in strong noise. 展开更多
关键词 second generation wavelet transform local mean decomposition(LMD) feature extraction fault diagnosis
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基于混沌粒子群的第2代小波的局部放电信号去噪 被引量:4
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作者 贾亚飞 李鸿禄 +1 位作者 李春耕 朱永利 《电力系统及其自动化学报》 CSCD 北大核心 2017年第3期62-68,共7页
输变电设备局部放电信号在线监测过程会受到多种噪声污染,使得局部放电信号难以提取。该文提出了一种基于混沌粒子群优化算法的第2代小波的去噪方法,在第2代小波及插值细分方法基本原理的基础上,将混沌粒子群优化算法引入预测器和更新... 输变电设备局部放电信号在线监测过程会受到多种噪声污染,使得局部放电信号难以提取。该文提出了一种基于混沌粒子群优化算法的第2代小波的去噪方法,在第2代小波及插值细分方法基本原理的基础上,将混沌粒子群优化算法引入预测器和更新器设计中,并改进了重构过程中奇偶序列合并中存在的不匹配问题。通过分别对含有噪声的仿真和实测局部放电信号进行去噪处理,并与传统小波去噪进行对比分析,结果表明基于混沌粒子群优化算法的第2代小波具有快速、高效、实现灵活方便的特点,对局部放电信号具有更好的去噪效果。该方法在局部放电信号处理中有广泛的应用前景。 展开更多
关键词 局部放电 第2代小波 混沌粒子群 去噪
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一种新的水声目标辐射噪声特征提取模型 被引量:2
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作者 胡桥 郝保安 +2 位作者 吕林夏 陈亚林 孙起 《鱼雷技术》 2008年第6期38-43,共6页
针对复杂环境中水声目标辐射噪声特征难以准确提取的问题,提出了一种新的基于第二代小波变换(SG-WT)、改进的经验模式分解(EMD)和Hilbert包络解调分析(HESA)的水声目标辐射噪声特征提取模型。首先,该模型利用SGWT滤除水声目标的非平稳... 针对复杂环境中水声目标辐射噪声特征难以准确提取的问题,提出了一种新的基于第二代小波变换(SG-WT)、改进的经验模式分解(EMD)和Hilbert包络解调分析(HESA)的水声目标辐射噪声特征提取模型。首先,该模型利用SGWT滤除水声目标的非平稳辐射噪声信号中的噪声成分;其次,通过改进的EMD方法对滤波后的信号进行分解,提取信号的本征模式分量;最后,对这些本征模式分量进行HESA处理,从而实现辐射噪声特征的提取。将该模型应用在仿真和实测的水声目标辐射噪声数据的特征提取中,测试结果表明,同常规的小波滤波和HESA相比,该模型能够有效地提取出辐射噪声特征。 展开更多
关键词 第2代小波变换(sgwt) 改进的经验模式分解(EMD) Hilbert包络解调分析(HESA) 辐射噪声 特征提取
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A New OFDM System Based on Lifting Wavelet Transform for Wireless Channel 被引量:2
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作者 GAO Jian-bo ZHAO Er-yuan 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2005年第3期21-25,共5页
It is well known that the Orthogonal Frequency Division Multiplexing ( OFDM ) system has a high ability to overcome the effect of multipath and can obtain high spectral efficiency in the wireless communication chann... It is well known that the Orthogonal Frequency Division Multiplexing ( OFDM ) system has a high ability to overcome the effect of multipath and can obtain high spectral efficiency in the wireless communication channel. However, avoid Interchannel Interference (ICI) and Intersymbol Interference (ISI) in wireless channel, a guard interval longer than channel delay is used in conventional OFDM system, which cause the efficiency of bandwidth usage reduced. Due to the superior spectral containment of wavelets, this paper proposed a new OFDM system based on Lifting Wavelet Transform (LWT-OFDM), which adopts lifting wavelet transform to replace the conventional Fourier transform. This new OFDM system doesn't need the Cyclic Prefix (CP) so its structure is more simply than FFT-OFDM and its algorithm is as simply as FFT-OFDM. The new LWT-OFDM system can mitigates some disadvantages of FFT-OFDM system, such as a relatively large peak-to-average power ratio, more sensitive to carrier frequency offset and phase noise. Simulations show that the LWT-OFDM system is more effective and attractive than conversional FFT-OFDM in wireless channel. 展开更多
关键词 OFDM 4G wavelet transform lifting theory. the second generation wavelet signal processing
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结合二代小波与快速傅里叶变换的电能质量数据压缩算法 被引量:3
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作者 张乐平 丁泽俊 +1 位作者 夏锐 郭飞飞 《南方电网技术》 2013年第3期89-93,共5页
针对大量电能质量数据的传输和储存问题,提出一种结合快速傅里叶变换(FFT)和二代小波(SGWT)的电能质量数据压缩算法,包括FFT、SGWT有损压缩和LZW(字符串表编码)无损压缩的流程图。分别对暂态和稳态扰动信号进行仿真比较,结果表明所提出... 针对大量电能质量数据的传输和储存问题,提出一种结合快速傅里叶变换(FFT)和二代小波(SGWT)的电能质量数据压缩算法,包括FFT、SGWT有损压缩和LZW(字符串表编码)无损压缩的流程图。分别对暂态和稳态扰动信号进行仿真比较,结果表明所提出的算法与FFT以及SGWT相比,可有效降低存储空间,可得到更高的压缩率且在压缩比、均方误差与运行时间等性能指标上取得较好平衡。 展开更多
关键词 快速傅里叶变换 二代小波变换 字符串表编码 电能质量 数据压缩
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