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Abundance quantification by independent component analysis of hyperspectral imagery for oil spill coverage calculation 被引量:2
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作者 韩仲志 万剑华 +1 位作者 张杰 张汉德 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第4期978-986,共9页
The estimation of oil spill coverage is an important part of monitoring of oil spills at sea.The spatial resolution of images collected by airborne hyper-spectral remote sensing limits both the detection of oil spills... The estimation of oil spill coverage is an important part of monitoring of oil spills at sea.The spatial resolution of images collected by airborne hyper-spectral remote sensing limits both the detection of oil spills and the accuracy of estimates of their size.We consider at-sea oil spills with zonal distribution in this paper and improve the traditional independent component analysis algorithm.For each independent component we added two constraint conditions:non-negativity and constant sum.We use priority weighting by higher-order statistics,and then the spectral angle match method to overcome the order nondeterminacy.By these steps,endmembers can be extracted and abundance quantified simultaneously.To examine the coverage of a real oil spill and correct our estimate,a simulation experiment and a real experiment were designed using the algorithm described above.The result indicated that,for the simulation data,the abundance estimation error is 2.52% and minimum root mean square error of the reconstructed image is 0.030 6.We estimated the oil spill rate and area based on eight hyper-spectral remote sensing images collected by an airborne survey of Shandong Changdao in 2011.The total oil spill area was 0.224 km^2,and the oil spill rate was 22.89%.The method we demonstrate in this paper can be used for the automatic monitoring of oil spill coverage rates.It also allows the accurate estimation of the oil spill area. 展开更多
关键词 oil spill hyperspectral imagery endmember extraction abundance quantification independent component analysis ica
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Two Dimensional Spatial Independent Component Analysis and Its Application in fMRI Data Process
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作者 陈华富 尧德中 《Journal of Electronic Science and Technology of China》 2005年第3期231-233,237,共4页
One important application of independent component analysis (ICA) is in image processing. A two dimensional (2-D) composite ICA algorithm framework for 2-D image independent component analysis (2-D ICA) is propo... One important application of independent component analysis (ICA) is in image processing. A two dimensional (2-D) composite ICA algorithm framework for 2-D image independent component analysis (2-D ICA) is proposed. The 2-D nature of the algorithm provides it an advantage of circumventing the roundabout transforming procedures between two dimensional (2-D) image deta and one-dimensional (l-D) signal. Moreover the combination of the Newton (fixed-point algorithm) and natural gradient algorithms in this composite algorithm increases its efficiency and robustness. The convincing results of a successful example in functional magnetic resonance imaging (fMRI) show the potential application of composite 2-D ICA in the brain activity detection. 展开更多
关键词 independent component analysis image processing composite 2-D ica algorithm functional magnetic resonance imaging
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An Improved Fixed-point Algorithm for Independent Component Analysis of Functional MRI Data
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作者 WENG Xiao-guang WANG Hui-nan QIAN Zhi-yu 《Chinese Journal of Biomedical Engineering(English Edition)》 2009年第2期78-83,共6页
The fixed-point algorithm and infomax algorithm are two of the most popular algorithms in independent component analysis(ICA).However,it is hard to take both stability and speed into consideration in processing functi... The fixed-point algorithm and infomax algorithm are two of the most popular algorithms in independent component analysis(ICA).However,it is hard to take both stability and speed into consideration in processing functional magnetic resonance imaging(fMRI)data.In this paper,an optimization model for ICA is presented and an improved fixed-point algorithm based on the model is proposed.In the new algorithms a small step size is added to increase the stability.In order to accelerate the convergence,an improvement on Newton method is made,which makes cubic convergence for the new algorithm.Applying the algorithm and two other algorithms to invivo fMRI data,the results show that the new algorithm separates independent components stably,which has faster convergence speed and less computation than the other two algorithms.The algorithm has obvious advantage in processing fMRI signal with huge data. 展开更多
关键词 independent component analysisica functional magnetic reasonance imaging(fMRI) Newton iteration
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SIGNAL FEATURE EXTRACTION BASED UPON INDEPENDENT COMPONENT ANALYSIS AND WAVELET TRANSFORM 被引量:7
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作者 JiZhong JinTao QinShuren 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第1期123-126,共4页
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... 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. 展开更多
关键词 independent component analysis (ica) Wavelet transform DE-NOISING FAULTDIAGNOSIS Feature extraction
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Independent component analysis approach for fault diagnosis of condenser system in thermal power plant 被引量:6
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作者 Ajami Ali Daneshvar Mahdi 《Journal of Central South University》 SCIE EI CAS 2014年第1期242-251,共10页
A statistical signal processing technique was proposed and verified as independent component analysis(ICA) for fault detection and diagnosis of industrial systems without exact and detailed model.Actually,the aim is t... A statistical signal processing technique was proposed and verified as independent component analysis(ICA) for fault detection and diagnosis of industrial systems without exact and detailed model.Actually,the aim is to utilize system as a black box.The system studied is condenser system of one of MAPNA's power plants.At first,principal component analysis(PCA) approach was applied to reduce the dimensionality of the real acquired data set and to identify the essential and useful ones.Then,the fault sources were diagnosed by ICA technique.The results show that ICA approach is valid and effective for faults detection and diagnosis even in noisy states,and it can distinguish main factors of abnormality among many diverse parts of a power plant's condenser system.This selectivity problem is left unsolved in many plants,because the main factors often become unnoticed by fault expansion through other parts of the plants. 展开更多
关键词 CONDENSER fault detection and diagnosis independent component analysis independent component analysis ica principal component analysis (PCA) thermal power plant
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Study of engine noise based on independent component analysis 被引量:6
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作者 HAO Zhi-yong JIN Yan YANG Chen 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第5期772-777,共6页
Independent component analysis was applied to analyze the acoustic signals from diesel engine. First the basic prin-ciple of independent component analysis (ICA) was reviewed. Diesel engine acoustic signal was decompo... Independent component analysis was applied to analyze the acoustic signals from diesel engine. First the basic prin-ciple of independent component analysis (ICA) was reviewed. Diesel engine acoustic signal was decomposed into several inde-pendent components (ICs); Fourier transform and continuous wavelet transform (CWT) were applied to analyze the independent components. Different noise sources of the diesel engine were separated, based on the characteristics of different component in time-frequency domain. 展开更多
关键词 Acoustic signals independent component analysis ica Wavelet transform Noise source identification
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Independent Component Analysis Based Blind Adaptive Interference Reduction and Symbol Recovery for OFDM Systems 被引量:4
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作者 LUO Zhongqiang ZHU Lidong LI Chengjie 《China Communications》 SCIE CSCD 2016年第2期41-54,共14页
To overcome the inter-carrier interference (ICI) of orthogonal frequency division multiplexing (OFDM) systems subject to unknown carrier frequency offset (CFO) and multipath, this paper develops a blind adaptive... To overcome the inter-carrier interference (ICI) of orthogonal frequency division multiplexing (OFDM) systems subject to unknown carrier frequency offset (CFO) and multipath, this paper develops a blind adaptive interference suppression scheme based on independent component analysis (ICA). Taking into account statistical independence of subcarriers' signals of OFDM, the signal recovery mechanism is investigated to achieve the goal of blind equalization. The received OFDM signals can be considered as the mixed observation signals. The effect of CFO and multipath corresponds to the mixing matrix in the problem of blind source separation (BSS) framework. In this paper, the ICA- based OFDM system model is built, and the proposed ICA-based detector is exploited to extract source signals from the observation of a received mixture based on the assumption of statistical independence between the sources. The blind separation technique can increase spectral efficiency and provide robustness performance against erroneous parameter estimation problem. Theoretical analysis and simulation results show that compared with the conventional pilot-based scheme, the improved performance of OFDM systems is obtained by the proposed ICA-based detection technique. 展开更多
关键词 orthogonal frequency divisionmultiplexing (OFDM) blind source separation(BSS) independent component analysis ica blind interference suppression symbol recovery
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A Simple and Accurate ICA Algorithm for Separating Mixtures of Up to Four Independent Components 被引量:3
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作者 TANG Ying LI Jian-Ping WU Huai 《自动化学报》 EI CSCD 北大核心 2011年第7期794-799,共6页
这份报纸用二的明确的关上的形式为独立部件分析(集成通信适配器) 介绍一个算法 -- ,三 -- 并且没有任何近似,四维的反对称的矩阵 exponentials,搜索方向和矩阵 exponentials 能基于是直接在每次重复计算了。另外,二个错误为在另外... 这份报纸用二的明确的关上的形式为独立部件分析(集成通信适配器) 介绍一个算法 -- ,三 -- 并且没有任何近似,四维的反对称的矩阵 exponentials,搜索方向和矩阵 exponentials 能基于是直接在每次重复计算了。另外,二个错误为在另外的工作被建立的四维的反对称的矩阵 exponentials 的表示被改正了。模拟证明算法快收敛并且能为多达四个独立部件的混合物比著名扩大 InfoMax 和 FastICA 算法完成更好的性能。 展开更多
关键词 自动化系统 自动化技术 ica 数据处理
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Online Batch Process Monitoring Based on Just-in-Time Learning and Independent Component Analysis 被引量:1
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作者 WANG Li SHI Hong-bo 《Journal of Donghua University(English Edition)》 EI CAS 2016年第6期944-948,共5页
A new method was developed for batch process monitoring in this paper. In the devdopad method, just-in-time learning ( JITL ) and independent component analysis (ICA) were integrated to build JITL-ICA monitoring s... A new method was developed for batch process monitoring in this paper. In the devdopad method, just-in-time learning ( JITL ) and independent component analysis (ICA) were integrated to build JITL-ICA monitoring scheme. JITL was employed to tackle with the characteristics of batch process such as inherent time- varying dynamics, multiple operating phases, and especially the case of uneven length stage. According to new coming test data, the most correlated segmentation was obtained from batch-wise unfolded training data by JITL. Then, ICA served as the principal components extraction approach. Therefore, the non.Gaussian distributed data can also be addressed under this modeling framework. The effectiveness and superiority of JITL-ICA based monitoring method was demonstrated by fed-batch penicillin fermentation. 展开更多
关键词 batch process monitoring just-in-time learning(JITL) independent component analysis(ica)
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Fault diagnosis method for an Aeroengine Based on Independent Component Analysis and the Discrete Hidden Markov Model 被引量:1
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作者 MA Jian-cang ZENG Yuan 《International Journal of Plant Engineering and Management》 2009年第4期193-201,共9页
The vibration signals of an aeroengine are a very important information source for fault diagnosis and condition monitoring. Considering the nonstationarity and low repeatability of the vibration signals, it is necess... The vibration signals of an aeroengine are a very important information source for fault diagnosis and condition monitoring. Considering the nonstationarity and low repeatability of the vibration signals, it is necessary to find a corresponding method for feature extraction and fault recognition. In this paper, based on Independent Component Analysis (ICA) and the Discrete Hidden Markov Model (DHMM), a new fault diagnosis approach named ICA-DHMM is proposed. In this method, ICA separates the source signals from the mixed vibration signals and then extracts features from them, DHMM works as a classifier to recognize the conditions of the aeroengine. Compared with the DHMM, which use the amplitude spectrum of mixed signals as feature parameters, experimental results show this method has higher diagnosis accuracy. 展开更多
关键词 independent component analysis ica feature extraction discrete hidden Markov model DHMM) AEROENGINE fault diagnosis
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Foreground Detection Based on Nonlinear Independent Component Analysis
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作者 HAN Guang WANG Jin-kuan CAI Xi 《Journal of Donghua University(English Edition)》 EI CAS 2016年第6期831-835,共5页
Motionless foreground objects are key targets in applications of home care monitoring and abandoned object detection, and pose a great challenge to foreground detection. Most algorithms incorporate the motionless fore... Motionless foreground objects are key targets in applications of home care monitoring and abandoned object detection, and pose a great challenge to foreground detection. Most algorithms incorporate the motionless foreground objects into their background models because they have to adapt to environmental changes. To overcome this challenge, a foreground detection method based on nonlinear independent component analysis (ICA) was proposed. Considering that each video frame was actually a nonlinear mixture of the background image and the foreground image, the nonlinear ICA was employed to accurately separate the independent components from each frame. Then, the entropy of grayscale image was calculated to classify which resulting independent component was the foreground image. The proposed nonlinear ICA model was trained offiine and this model was not updated online, so the method can cope with the motionless foreground objects. Experimental results demonstrate that, the method achieves remarkable results and outperforms several advanced methods in dealing with the motionless foreground objects. 展开更多
关键词 foreground detection nonlinear independent component analysis(ica) motionless foreground objects
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Detection and Separation of Event-related Potentials from Multi-Artifacts Contaminated EEG by Means of Independent Component Analysis
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作者 WANGRong-chang DUSi-dan GAODun-tang 《Chinese Journal of Biomedical Engineering(English Edition)》 2004年第4期152-161,共10页
Event-related potentials (ERP) is an important type of brain dynamics in human cognition research. However, ERP is often submerged by the spontaneous brain activity EEG, for its relatively tiny scale. Further more, th... Event-related potentials (ERP) is an important type of brain dynamics in human cognition research. However, ERP is often submerged by the spontaneous brain activity EEG, for its relatively tiny scale. Further more, the brain activities collected from scalp electrodes are often inevitably contaminated by several kinds of artifacts, such as blinks, eye movements, muscle noise and power line interference. A new approach to correct these disturbances is presented using independent component analysis (ICA). This technique can effectively detect and extract ERP components from the measured electrodes recordings even if they are heavily contaminated. The results compare favorably to those obtained by parametric modeling. Besides, auto-adaptive projection of decomposed results to ERP components was also given. Through experiments, ICA proves to be highly capable of ERP extraction and S/N ratio improving. 展开更多
关键词 ERP independent component analysis (ica) Blind Source Separation (BSS) ARX Modeling
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Process Monitoring Based on Independent Component Contribution
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作者 吕小条 宋冰 +1 位作者 侍洪波 谭帅 《Journal of Donghua University(English Edition)》 EI CAS 2017年第3期349-354,共6页
Independent component analysis( ICA) has been widely applied to the monitoring of non-Gaussian processes. Despite lots of applications,there is no universally accepted criterion to select the dominant independent comp... Independent component analysis( ICA) has been widely applied to the monitoring of non-Gaussian processes. Despite lots of applications,there is no universally accepted criterion to select the dominant independent components( ICs). Moreover, how to determine the number of dominant ICs is still an open question. To further address this issue,a novel process monitoring based on IC contribution( ICC) is proposed from the perspective of information storage. Based on the ICC with each variable,the dominant ICs can be obtained and the number of dominant ICs is determined objectively. To further preserve the process information, the remaining ICs are not useless. As a result,all the ICs are regarded to be divided into dominant and residual subspaces. The monitoring models are established respectively in each subspace, and then Bayesian inference is applied to integrating monitoring results of the two subspaces. Finally, the feasibility and effectiveness of the proposed method are illustrated through a numerical example and the Tennessee Eastman process. 展开更多
关键词 independent Eastman Tennessee Bayesian preserve illustrated criterion universally remaining integrating
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基于SOA-VMD-ICA的海水泵激励源特征提取方法
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作者 滕佳篷 武国启 《中国机械工程》 EI CAS CSCD 北大核心 2024年第8期1373-1380,共8页
针对海水泵复杂多源激励特征提取问题,提出了一种海鸥优化算法(SOA)、变分模态分解(VMD)和独立分量分析(ICA)相结合的海水泵激励源特征提取方法。基于单通道测量信号,采用VMD算法与SOA算法选取信号平方包络谱峭度统计量作为适应度函数,... 针对海水泵复杂多源激励特征提取问题,提出了一种海鸥优化算法(SOA)、变分模态分解(VMD)和独立分量分析(ICA)相结合的海水泵激励源特征提取方法。基于单通道测量信号,采用VMD算法与SOA算法选取信号平方包络谱峭度统计量作为适应度函数,寻优获取模态分解数量K、惩罚系数α及特征模态函数(IMF)分量。采用信号排列熵作为噪声检验函数,合理选取排列熵阈值,对IMF分量进行噪声筛选,获取非噪声IMF分量信号。将非噪声IMF分量与原输入信号组合,采用快速独立成分分析(Fast-ICA)算法计算得到激励源信号向量,从而实现激励源特征信号的提取。通过实船海水泵激励源特征提取试验及对比分析,验证了所提方法的有效性。研究结果表明,所提的SOA-VMD-ICA方法能满足单通道测量条件海水泵激励源特征提取准确性要求。 展开更多
关键词 特征提取 海水泵 独立分量分析 海鸥优化算法 变分模态分解
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A post-modification approach to independent compo-nent analysis for resolution of overlapping GC/MS signals: from independent components to chemical components 被引量:1
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作者 WANG Wei CAI WenSheng SHAO XueGuang 《Science China Chemistry》 SCIE EI CAS 2007年第4期530-537,共8页
Independent component analysis (ICA) has demonstrated its power to extract mass spectra from over-lapping GC/MS signal. However, there is still a problem that mass spectra with negative peaks at some m/z will be obtai... Independent component analysis (ICA) has demonstrated its power to extract mass spectra from over-lapping GC/MS signal. However, there is still a problem that mass spectra with negative peaks at some m/z will be obtained in the resolved results when there are overlapping peaks in the mass spectra of a mixture. Based on a detail theoretical analysis of the preconditions for ICA and the non-negative property of GC/MS signals, a post-modification based on chemical knowledge (PMBK) strategy is pro-posed to solve this problem. By both simulated and experimental GC/MS signals, it was proved that the PMBK strategy can improve the resolution effectively. 展开更多
关键词 independent component analysis (ica) post modification IMMUNE algorithm (IA) GC/MS
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A new method for fMRI data processing: Neighborhood independent component correlation algorithm and its preliminary application 被引量:8
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作者 陈华富 尧德中 +2 位作者 卓彦 曾敏 陈霖 《Science in China(Series F)》 EI 2002年第5期373-382,共10页
Independent component analysis (ICA) is a newly developed promising technique in signal processing applications. The effective separation and discrimination of functional Magnetic Resonance Imaging (fMRI) signals is a... Independent component analysis (ICA) is a newly developed promising technique in signal processing applications. The effective separation and discrimination of functional Magnetic Resonance Imaging (fMRI) signals is an area of active research and widespread interest. Therefore, the development of an ICA based fMRI data processing method is of obvious value both theoretically and in potential applications. In this paper, analyzed firstly is the drawback of the extant popular ICA-fMRI method where the adopted signal model assumes the independence of spatial distributions of the signals and noise. Then presented is a new fMRI signal model, which assumes the independence of temporal courses of signal and noise in a tiny spatial domain. Consequently we get a novel fMRI data processing method: Neighborhood independent component correlation algorithm. The effectiveness is elucidated through theoretical analysis and simulation tests, and finally a real fMRI data test is presented. 展开更多
关键词 functional Magnetic Resonance Imaging (fMRI) independent component analysis (ica) spatial distribution temporal process signal model.
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Novel infrared and visible image fusion method based on independent component analysis 被引量:4
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作者 Yin LU Fuxiang WANG Xiaoyan LUO Feng LIU 《Frontiers of Computer Science》 SCIE EI CSCD 2014年第2期243-254,共12页
The goal of infrared (IR) and visible image fu- sion is for the fused image to contain IR object features from the IR image and retain the visual details provided by the visible image. The disadvantage of traditiona... The goal of infrared (IR) and visible image fu- sion is for the fused image to contain IR object features from the IR image and retain the visual details provided by the visible image. The disadvantage of traditional fusion method based on independent component analysis (ICA) is that the primary feature information that describes the IR objects and the secondary feature information in the IR image are fused into the fused image. Secondary feature information can de- press the visual effect of the fused image. A novel ICA-based IR and visible image fusion scheme is proposed in this paper. ICA is employed to extract features from the infrared image, and then the primary and secondary features are distinguished by the kurtosis information of the ICA base coefficients. The secondary features of the IR image are discarded during fu- sion. The fused image is obtained by fusing primary features into the visible image. Experimental results show that the pro- posed method can provide better perception effect. 展开更多
关键词 image fusion independent component analysisica feature extraction KURTOSIS
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Blind noisy image separation based on a new robust independent component analysis network 被引量:3
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作者 纪建 田铮 《Chinese Optics Letters》 SCIE EI CAS CSCD 2006年第10期573-575,共3页
The separation of noisy image is a very exciting area of research, especially when no prior information is available about the noisy image. In this paper, we propose a robust independent component analysis (ICA) net... The separation of noisy image is a very exciting area of research, especially when no prior information is available about the noisy image. In this paper, we propose a robust independent component analysis (ICA) network for separation images contaminated with high-level additive noise or outliers. We reduce the power of additive noise by adding outlier rejection rule in ICA. Extensive computer simulations confirm robustness and the excellent performance of the resulting algorithms. 展开更多
关键词 algorithmS Computer simulation independent component analysis
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基于CEEMDAN和ICA的油气勘探大地电磁噪声消除方法 被引量:2
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作者 曹小玲 唐新功 蒋涛 《石油地球物理勘探》 EI CSCD 北大核心 2023年第3期740-750,共11页
大地电磁(MT)信号中的噪声会严重影响大地电磁勘探的观测数据,导致后续反演、解释工作出现严重偏差,影响油气勘探效果。为此,提出了一种基于带自适应噪声的完全集合经验模态分解(CEEMDAN)和独立分量分析(ICA)的噪声消除方法。该方法将... 大地电磁(MT)信号中的噪声会严重影响大地电磁勘探的观测数据,导致后续反演、解释工作出现严重偏差,影响油气勘探效果。为此,提出了一种基于带自适应噪声的完全集合经验模态分解(CEEMDAN)和独立分量分析(ICA)的噪声消除方法。该方法将经验模态分解(EMD)中的CEEMDAN方法与盲源分离(BSS)中的ICA方法进行有效结合。首先,利用改进的端点检测技术识别电磁信号中的有噪声信号分段;其次,利用CEEMDAN方法对其进行分解,提取具有代表性的固有模态分量(IMF)分量并进行ICA处理,达到消除噪声的目的;然后,利用获得的独立分量对有用MT信号进行逆向重构;最后,将未受噪声污染的MT信号与去噪后的有用MT信号进行拼接,获得最终的消噪后的完整MT信号。对合成信号和实测MT数据的实验结果表明,该方法能有效消除MT信号中的噪声。 展开更多
关键词 大地电磁 带自适应噪声的完全集合经验模态分解(CEEMDAN) 独立分量分析(ica) 去噪
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State Inspection for Transmission Lines Based on Independent Component Analysis
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作者 任丽佳 江秀臣 +1 位作者 盛戈嗥 杨巍巍 《Journal of Shanghai Jiaotong university(Science)》 EI 2009年第2期129-132,共4页
Monitoring transmission towers is of great importance to prevent severe thefts on them and ensure the reliability and safety of the power grid operation.Independent component analysis(ICA) is a method for finding unde... Monitoring transmission towers is of great importance to prevent severe thefts on them and ensure the reliability and safety of the power grid operation.Independent component analysis(ICA) is a method for finding underlying factors or components from multivariate statistical data based on dimension reduction methods,and it is applicable to extract the non-stationary signals.FastICA based on negentropy is presented to effectively extract and separate the vibration signals caused by human activity in this paper.A new method combined empirical mode decomposition(EMD) technique with the adaptive threshold method is applied to extract the vibration pulses,and suppress the interference signals.The practical tests demonstrate that the method proposed in the paper is effective in separating and extracting the vibration signals. 展开更多
关键词 state inspection transmission lines independent component analysis ica NEGENTROPY adaptive threshold empirical mode decomposition (EMD)
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