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非局部降噪快速模糊C-均值聚类算法
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作者 李彬 陈武凡 《计算机工程与应用》 CSCD 北大核心 2009年第35期21-23,27,共4页
传统的模糊C-均值聚类算法未利用图像的空间信息,在分割迭加了噪声的MR图像时分割精度较差。采用了既能有效去除噪声又能较好地保持图像边缘特征的非局部降噪方法,结合基于图像灰度直方图聚类分析的快速模糊C-均值聚类算法,得到了一种... 传统的模糊C-均值聚类算法未利用图像的空间信息,在分割迭加了噪声的MR图像时分割精度较差。采用了既能有效去除噪声又能较好地保持图像边缘特征的非局部降噪方法,结合基于图像灰度直方图聚类分析的快速模糊C-均值聚类算法,得到了一种具有较高分割精度的图像快速分割算法。通过对模拟图像、仿真脑部MR图像和临床脑部MR图像的分割实验,表明提出的新算法比已有的快速模糊C-均值聚类算法有更精确的图像分割能力。 展开更多
关键词 非局部滤波器 快速模糊C-均值聚类算法 图像分割
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自适应滤波技术研究及在船舶检测方面的应用
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作者 郝力佳 冯武卫 《浙江海洋学院学报(自然科学版)》 CAS 2017年第2期166-171,共6页
研究了自适应噪声消除技术,利用Wiener滤波理论解释和研究自适应滤波器的功能。研究表明,当没有可用信号和其他条件满足参考输入时,主输入中的噪声也可以基本上消除,并且没有信号失真,证明了该方法的有效性。本文还研究了自适应消噪在... 研究了自适应噪声消除技术,利用Wiener滤波理论解释和研究自适应滤波器的功能。研究表明,当没有可用信号和其他条件满足参考输入时,主输入中的噪声也可以基本上消除,并且没有信号失真,证明了该方法的有效性。本文还研究了自适应消噪在船舶检测方面的应用,包括消除语音信号中的周期性干扰,消除播放宽屏带信号期间磁带嗡嗡声或转盘隆隆声,以及被宽带噪声掩盖的低频周期信号的自动检测,得到了良好的效果。 展开更多
关键词 自适应滤波 维纳法 声消除 滤波器降噪应用
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基于数据挖掘的光纤通信故障数据诊断方法研究 被引量:3
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作者 贾丽 刘欣 郭健 《激光杂志》 CAS 北大核心 2023年第8期177-181,共5页
针对传统方法进行光纤通信故障数据诊断时易受噪声条件、光照变化、信号强度等问题干扰,诊断精准度不高的问题,提出基于数据挖掘的光纤通信故障数据诊断方法研究。首先利用滤波器剔除光纤通信数据中的噪声,以避免噪声对故障诊断结果产... 针对传统方法进行光纤通信故障数据诊断时易受噪声条件、光照变化、信号强度等问题干扰,诊断精准度不高的问题,提出基于数据挖掘的光纤通信故障数据诊断方法研究。首先利用滤波器剔除光纤通信数据中的噪声,以避免噪声对故障诊断结果产生影响,其次利用主成分分析法提取数据的特征,最后将提取的特征输入到最小二乘支持向量机中,采用粒子群算法优化最小二乘支持向量机参数,输出故障分类结果,完成光纤通信故障数据的诊断。测试结果表明,所提方法的信号提取效果好、诊断精确率高、召回率高、F1分数高。 展开更多
关键词 滤波器降噪 时间序列 主成分分析法 最佳分类平面 参数优化
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Improved Goldstein filter for InSAR noise reduction based on local SNR 被引量:7
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作者 SUN Qian LI Zhi-wei +3 位作者 ZHU Jian-jun DING Xiao-li HU Jun XU Bing 《Journal of Central South University》 SCIE EI CAS 2013年第7期1896-1903,共8页
Although the modified Goldstein filter based on the local signal-to-noise (SNR) has been proved to be superior to the classical Goldstein and Baran filters with more comprehensive filter parameter, its adaptation is... Although the modified Goldstein filter based on the local signal-to-noise (SNR) has been proved to be superior to the classical Goldstein and Baran filters with more comprehensive filter parameter, its adaptation is not always sufficient in the reduction of phase noise. In this work, the local SNR-based Goldstein filter is further developed with the improvements in the definition of the local SNR and the adaption of the filtering patch size. What's more, for preventing the loss of the phase signal caused by the excessive filtering, an iteration filtering operation is also introduced in this new algorithm. To evaluate the performance of the proposed algorithm, both a simulated digital elevation model (DEM) interferogram and real SAR deformation interferogram spanning the L' Aquila earthquake are carried out. The quantitative results from the simulated and real data reveal that up to 79.5% noises can be reduced by the new filter, indicating 9%-32% improvements over the previous local SNR-based Goldstein filter. This demonstrates that the new filter is not only equipped with sufficient adaption, but also can suppress the phase noise without the sacrifice of the phase signal. 展开更多
关键词 interferometric synthetic aperture radar (InSAR) Goldstein filter signal-to-noise (SNR) adaptivity
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Lifting transform via Savitsky-Golay filter predictor and application of denoising 被引量:3
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作者 周广柱 杨锋杰 王翠珍 《Journal of Coal Science & Engineering(China)》 2006年第2期66-69,共4页
The Savitsky-Golay filter isa smoothing filter based on polynomial regression.Itemploys the regression fitting capacity to improve the smoothing results.But Savit-sky-Golay filter uses a fix sized window.It has the sa... The Savitsky-Golay filter isa smoothing filter based on polynomial regression.Itemploys the regression fitting capacity to improve the smoothing results.But Savit-sky-Golay filter uses a fix sized window.It has the same shortage of Window FourierTransform.Wavelet mutiresolution analysis may deal with this problem.In this paper,tak-ing advantage of Savitsky-Golay filter's fitting ability and the wavelet transform's multiscaleanalysis ability,we developed a new lifting transform via Savitsky-Golay smoothing filteras the lifting predictor,and then processed the signals comparing with the ordinary Savit-sky-Golay Smoothing method.We useed the new lifting in noisy heavy sine denoising.Thenew transform obviously has better denoise ability than ordinary Savitsky-Golay smooth-ing method.At the same time singular points are perfectly retained in the denoised signal.Singularity analysis,multiscale interpolation,estimation,chemical data smoothing andother potential signal processing utility of this new lifting transform are in prospect. 展开更多
关键词 lifting wavelet Savitsky-Golay filter PREDICTOR DENOISE
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Application of a joint algorithm based on L-T to pulse pressure detection signal of fiber Fabry-Perot nano pressure sensor
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作者 FENG Fei QIN Li 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2021年第1期61-67,共7页
An improved denoising method and its application in pulse beat signal denoising are studied.The proposed denoising algorithm takes the advantages of local mean decomposition(LMD)and time-frequency peak filtering(TFPF)... An improved denoising method and its application in pulse beat signal denoising are studied.The proposed denoising algorithm takes the advantages of local mean decomposition(LMD)and time-frequency peak filtering(TFPF),called L-T algorithm.As a classical time-frequency filtering method,TFPF can effectively suppress random noise with signal amplitude retained when selecting a longer window length,while the signal amplitude will be seriously attenuated when selecting a shorter window length.In order to maintain effective signal amplitude and suppress random noise,LMD and TFPF are improved.Firstly,the original signal is decomposed into progression-free survival(PFS)by LMD,and then the standard error of mean(SEM)of each product function is calculated to classify many PFSs into useful component,mixed component and noise component.Secondly,by using the shorter window TFPF for useful component and the longer window TFPF for mixed component,noise component is removed and the final signal is obtained after reconstruction.Finally,the proposed algorithm is used for noise reduction of an Fabry-Perot(F-P)pressure sensor.Experimental results show that compared with traditional wavelet,L-T algorithm has better denoising effect on sampled data. 展开更多
关键词 local mean decomposition(LMD) time-frequency peak filtering(TFPT) noise reduction Fabry-Perot(F-P)sensor
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