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Application of Singular Value Decomposition(SVD)to the Extraction of Gravity Anomalies Associated with Ag-Pb-Zn-W Polymetallic Mineralization in the Bozhushan Ore Field,Southwestern China 被引量:4
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作者 Lingfen Guo Yongqing Chen Binbin Zhao 《Journal of Earth Science》 SCIE CAS CSCD 2021年第2期310-317,共8页
The Bozhushan Ore Field,located at the western margin of the South China Block,is an important area for Ag-Pb-Zn-W polymetallic mineralization which may be associated with the Late Cretaceous granitic magmaism.In this... The Bozhushan Ore Field,located at the western margin of the South China Block,is an important area for Ag-Pb-Zn-W polymetallic mineralization which may be associated with the Late Cretaceous granitic magmaism.In this paper,the singular value decomposition(SVD)was effectively applied to decompose gravity data at scale of 1:50000 within the Bozhushan Ore Field to extract deep ore-finding information.Two gravity anomaly images displaying different scales of the ore-controlling factors were obtained.(1)The low-pass filtered image may reflect the deeply buried geological structures,hidden intrusions and concealed ore bodies.The negative gravity anomaly may reflect the overall distribution of granite bodies in the Bozhushan Ore Field.One negative gravity anomaly area may correspond to the exposed part of the Baozhushan granitic intrusion and the other corresponds to the concealed part of the granitic intrusion.The granitic intrusions are the main ore-controlling factors in this ore district.(2)The band-pass filtered image depicts the shallow concealed geological structures and geological bodies within this study area.There are two obvious negative gravity anomalies,which may be created by the hidden granites at different depths at both northwestern and southeastern sides of the exposed granitic intrusion.Thus the two negative gravity anomalies are favorable prospecting areas for various type of polymetallic ore deposits at depth.The gravity anomalies extracted by using the SVD exactly reflect the distribution of the ore deposits,structures and intrusions,which will give new insights for further mineral exploration in the study area. 展开更多
关键词 singular value decomposition(svd) gravity anomaly Ag-Pb-Zn-W polymetallic deposits Bozhushan granitic complex southwestern China
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DIRECT PERTURBATION METHOD FOR REANALYSIS OF MATRIX SINGULAR VALUE DECOMPOSITION
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作者 吕振华 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1997年第5期471-477,共7页
The perturbational reanalysis technique of matrix singular value decomposition is applicable to many theoretical and practical problems in mathematics, mechanics, control theory, engineering, etc.. An indirect perturb... The perturbational reanalysis technique of matrix singular value decomposition is applicable to many theoretical and practical problems in mathematics, mechanics, control theory, engineering, etc.. An indirect perturbation method has previously been proposed by the author in this journal, and now the direct perturbation method has also been presented in this paper. The second-order perturbation results of non-repeated singular values and the corresponding left and right singular vectors are obtained. The results can meet the general needs of most problems of various practical applications. A numerical example is presented to demonstrate the effectiveness of the direct perturbation method. 展开更多
关键词 matrix algebra singular value decomposition REANALYSIS perturbation method
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PERTURBATION METHOD FOR REANALYSIS OF THE MATRIX SINGULAR VALUE DECOMPOSITION
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作者 吕振华 冯振东 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1991年第7期705-715,共11页
The perturbation method for the reanalysis of the singular value decomposition (SVD) of general real matrices is presented in this paper. This is a simple but efficient reanalysis technique for the SVD, which is of gr... The perturbation method for the reanalysis of the singular value decomposition (SVD) of general real matrices is presented in this paper. This is a simple but efficient reanalysis technique for the SVD, which is of great worth to enhance computational efficiency of the iterative analysis problems that require matrix singular value decomposition repeatedly. The asymptotic estimate formulas for the singular values and the corresponding left and right singular vectors up to second-order perturbation components are derived. At the end of the paper the way to extend the perturbation method to the case of general complex matrices is advanced. 展开更多
关键词 matrix algebra singular value decomposition reanalysis perturbation method
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Contourlet watermarking algorithm based on Arnold scrambling and singular value decomposition 被引量:3
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作者 陈立全 孙晓燕 +1 位作者 卢苗 邵辰 《Journal of Southeast University(English Edition)》 EI CAS 2012年第4期386-391,共6页
A new digital watermarking algorithm based on the contourlet transform is proposed to improve the robustness and anti-attack performances of digital watermarking. The algorithm uses the Arnold scrambling technique and... A new digital watermarking algorithm based on the contourlet transform is proposed to improve the robustness and anti-attack performances of digital watermarking. The algorithm uses the Arnold scrambling technique and the singular value decomposition (SVD) scheme. The Arnold scrambling technique is used to preprocess the watermark, and the SVD scheme is used to find the best suitable hiding points. After the contourlet transform of the carrier image, intermediate frequency sub-bands are decomposed to obtain the singularity values. Then the watermark bits scrambled in the Arnold rules are dispersedly embedded into the selected SVD points. Finally, the inverse contourlet transform is applied to obtain the carrier image with the watermark. In the extraction part, the watermark can be extracted by the semi-blind watermark extracting algorithm. Simulation results show that the proposed algorithm has better hiding and robustness performances than the traditional contourlet watermarking algorithm and the contourlet watermarking algorithm with SVD. Meanwhile, it has good robustness performances when the embedded watermark is attacked by Gaussian noise, salt- and-pepper noise, multiplicative noise, image scaling and image cutting attacks, etc. while security is ensured. 展开更多
关键词 digital watermarking contourlet transform Arnold scrambling singular value decomposition svd
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The Singular Value Decomposition Analysis between Summer Precipitation in the Dongting Lake Region and the Global Sea Surface Temperature 被引量:1
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作者 彭莉莉 罗伯良 张超 《Meteorological and Environmental Research》 CAS 2010年第11期28-32,共5页
By dint of the summer precipitation data from 21 stations in the Dongting Lake region during 1960-2008 and the sea surface temperature(SST) data from NOAA,the spatial and temporal distributions of summer precipitation... By dint of the summer precipitation data from 21 stations in the Dongting Lake region during 1960-2008 and the sea surface temperature(SST) data from NOAA,the spatial and temporal distributions of summer precipitation and their correlations with SST are analyzed.The coupling relationship between the anomalous distribution in summer precipitation and the variation of SST has between studied with the Singular Value Decomposition(SVD) analysis.The increase or decrease of summer precipitation in the Dongting Lake region is closely associated with the SST anomalies in three key regions.The variation of SST in the three key regions has been proved to be a significant previous signal to anomaly of summer rainfall in Dongting region. 展开更多
关键词 Summer precipitation Sea surface temperature(SST) singular value decomposition(svd) analysis Dongting Lake China
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Analysis of heart rate variability based on singular value decomposition entropy 被引量:2
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作者 李世阳 杨明 +1 位作者 李存岑 蔡萍 《Journal of Shanghai University(English Edition)》 CAS 2008年第5期433-437,共5页
Assessing the dynamics of heart rate fluctuations can provide valuable information about heart status. In this study, regularity of heart rate variability (HRV) of heart failure patients and healthy persons using th... Assessing the dynamics of heart rate fluctuations can provide valuable information about heart status. In this study, regularity of heart rate variability (HRV) of heart failure patients and healthy persons using the concept of singular value decomposition entropy (SvdEn) is analyzed. SvdEn is calculated from the time series using normalized singular values. The advantage of this method is its simplicity and fast computation. It enables analysis of very short and non-stationary data sets. The results show that SvdEn of patients with congestive heart failure (CHF) shows a low value (SvdEn: 0.056±0.006, p 〈 0.01) which can be completely separated from healthy subjects. In addition, differences of SvdEn values between day and night are found for the healthy groups. SvdEn decreases with age. The lower the SvdEn values, the higher the risk of heart disease. Moreover, SvdEn is associated with the energy of heart rhythm. The results show that using SvdEn for discriminating HRV in different physiological states for clinical applications is feasible and simple. 展开更多
关键词 heart rate variability (HRV) singular value decomposition svd ENTROPY congestive heart failure (CHF)
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Pulsed Eddy Current Signal Denoising Based on Singular Value Decomposition 被引量:1
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作者 朱红运 王长龙 +1 位作者 陈海龙 王建斌 《Journal of Shanghai Jiaotong university(Science)》 EI 2016年第1期121-128,共8页
The noise as an undesired phenomenon often appears in the pulsed eddy current testing(PECT)signal, and it is difficult to recognize the character of the testing signal. One of the most common noises presented in the P... The noise as an undesired phenomenon often appears in the pulsed eddy current testing(PECT)signal, and it is difficult to recognize the character of the testing signal. One of the most common noises presented in the PECT signal is the Gaussian noise, since it is caused by the testing environment. A new denoising approach based on singular value decomposition(SVD) is proposed in this paper to reduce the Gaussian noise of PECT signal. The approach first discusses the relationship between signal to noise ratio(SNR) and negentropy of PECT signal. Then the Hankel matrix of PECT signal is constructed for noise reduction, and the matrix is divided into noise subspace and signal subspace by a singular valve threshold. Based on the theory of negentropy, the optimal matrix dimension and threshold are chosen to improve the performance of denoising. The denoised signal Hankel matrix is reconstructed by the singular values of signal subspace, and the denoised signal is finally extracted from this matrix. Experiment is performed to verify the feasibility of the proposed approach, and the results indicate that the proposed approach can reduce the Gaussian noise of PECT signal more effectively compared with other existing approaches. 展开更多
关键词 pulsed eddy current testing(PECT) singular value decomposition(svd) NEGENTROPY DENOISING
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Detection and correction of level echo based on generalized S-transform and singular value decomposition 被引量:1
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作者 ZHU Tianliang WANG Xiaopeng WANG Qi 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2021年第4期442-448,共7页
The echo of the material level is non-stationary and contains many singularities.The echo contains false echoes and noise,which affects the detection of the material level signals,resulting in low accuracy of material... The echo of the material level is non-stationary and contains many singularities.The echo contains false echoes and noise,which affects the detection of the material level signals,resulting in low accuracy of material level measurement.A new method for detecting and correcting the material level signal is proposed,which is based on the generalized S-transform and singular value decomposition(GST-SVD).In this project,the change of material level is regarded as the low speed moving target.First,the generalized S-transform is performed on the echo signals.During the transformation process,the variation trend of window of the generalized S-transform is adjusted according to the frequency distribution characteristics of the material level echo signal,achieving the purpose of detecting the signal.Secondly,the SVD is used to reconstruct the time-frequency coefficient matrix.At last,the reconstructed time-frequency matrix performs an inverse transform.The experimental results show that the method can accurately detect the material level echo signal,and it can reserve the detailed characteristics of the signal while suppressing the noise,and reduce the false echo interference.Compared with other methods,the material level measurement error does not exceed 4.01%,and the material level measurement accuracy can reach 0.40%F.S. 展开更多
关键词 echo signal false echo generalized S-transform singular value decomposition(svd) level measurement
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The Singular Value Decomposition as a Tool of Investigating Central MHD Instabilities in the HL-1M Tokamak
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作者 董云波 潘传红 +1 位作者 刘仪 付炳忠 《Plasma Science and Technology》 SCIE EI CAS CSCD 2004年第3期2307-2312,共6页
A variety of strong MHD instabilities are always resulted from MHD activity of Tokamak plasmas. Central MHD instabilities can be observed with pinhole cameras to record soft x-ray (SXR) emission from the plasma along ... A variety of strong MHD instabilities are always resulted from MHD activity of Tokamak plasmas. Central MHD instabilities can be observed with pinhole cameras to record soft x-ray (SXR) emission from the plasma along many chords with a high temporal resolution. The investigation of MHD instabilities often necessitates an analysis on spatial-temporal signals. The method of Singular Value Decomposition (SVD) can split such signals into orthogonal spatial and temporal vectors. By this means, the repetition time and the characteristic radius of various MHD phenomena such as sawteeth and snake-like perturbation can be obtained. Moreover, the (1,1) MHD mode is analyzed in great detail by SVD and used to determine the radius of the q = 1 surface. 展开更多
关键词 MHD instabilities soft x-ray (SXR) singular value decomposition (svd)
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基于改进SVD-EWT的环网柜局放信号自适应去噪方法
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作者 刘国伟 廖晓青 +3 位作者 陈历 梁汇 谭达禹 刘俊峰 《南方能源建设》 2026年第1期147-156,共10页
[目的]在电气设备的健康监测中,局部放电(Partial Discharge,PD)信号常受到各种噪声源的干扰,这些干扰主要来自设备自身的运行噪声或外部环境的干扰。[方法]为有效解决噪声干扰问题,提高局放检测的准确性和可靠性,提出一种基于频谱分析... [目的]在电气设备的健康监测中,局部放电(Partial Discharge,PD)信号常受到各种噪声源的干扰,这些干扰主要来自设备自身的运行噪声或外部环境的干扰。[方法]为有效解决噪声干扰问题,提高局放检测的准确性和可靠性,提出一种基于频谱分析的自适应奇异值分解(Singular Value Decomposition,SVD)和经验小波变换(Empirical Wavelet Transform,EWT)相结合的去噪算法。首先,对含噪PD信号进行快速傅里叶变换(Fast Fourier Transform,FFT)频谱分析,提出改进经典阈值和频谱幅值行向量峭度判别相结合的窄带干扰数量确定方法,重构并去除周期性窄带干扰噪声。随后,采用EWT算法对残留白噪声的PD信号进行自适应分解,筛选满足峭度条件的模态分量重构PD信号。最后,利用改进阈值方法去除重构信号中的少量白噪声,得到去噪后的PD信号。[结果]仿真及实测去噪处理结果表明,所提方法分别在信噪比、均方根误差、相关系数以及降噪率指标上达到7.02、0.0112、0.9003和33.0057。[结论]该方法能够有效去除窄带干扰及白噪声,相比于其他去噪方法,所提方法在多个评价指标上均有所改善,具有良好的去噪效果。 展开更多
关键词 电气环网柜 局部放电 频谱分析 奇异值分解 经验小波变换 改进阈值法
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An Approximate Linear Solver in Least Square Support Vector Machine Using Randomized Singular Value Decomposition
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作者 LIU Bing XIANG Hua 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2015年第4期283-290,共8页
In this paper, we investigate the linear solver in least square support vector machine(LSSVM) for large-scale data regression. The traditional methods using the direct solvers are costly. We know that the linear equ... In this paper, we investigate the linear solver in least square support vector machine(LSSVM) for large-scale data regression. The traditional methods using the direct solvers are costly. We know that the linear equations should be solved repeatedly for choosing appropriate parameters in LSSVM, so the key for speeding up LSSVM is to improve the method of solving the linear equations. We approximate large-scale kernel matrices and get the approximate solution of linear equations by using randomized singular value decomposition(randomized SVD). Some data sets coming from University of California Irvine machine learning repository are used to perform the experiments. We find LSSVM based on randomized SVD is more accurate and less time-consuming in the case of large number of variables than the method based on Nystrom method or Lanczos process. 展开更多
关键词 least square support vector machine Nystr?m method Lanczos process randomized singular value decomposition
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一种基于AE-SVD模态重心频率的汽车助力转向泵裂纹转子在线辨识研究
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作者 祝新军 李明 +2 位作者 金丹 裘杭锋 刘冬 《振动与冲击》 北大核心 2025年第19期257-263,共7页
针对汽车助力转向泵转子裂纹的动态辨识问题,提出了一种基于多传感器的声发射(acoustic emission,AE)重心频率的判定方法。首先,在同一个泵体中分别安装合格与裂纹转子,在同样的试验条件下从吸油和压油盘附近采集4路AE信号,采样频率为1 ... 针对汽车助力转向泵转子裂纹的动态辨识问题,提出了一种基于多传感器的声发射(acoustic emission,AE)重心频率的判定方法。首先,在同一个泵体中分别安装合格与裂纹转子,在同样的试验条件下从吸油和压油盘附近采集4路AE信号,采样频率为1 MHz;然后,从4个传感器采集的AE信号中按照单个周期长度截取子信号,经白化处理后构造AE信号矩阵,并对AE信号矩阵进行奇异值分解(singular value decomposition,SVD),根据分解结果提取4个正交模态向量;最后,对每个正交模态进行3层小波包分解,分别计算第3层前4个节点的重心频率,并通过与阈值的比较实现裂纹转子的判定。研究结果表明,在压力7 MPa和转速1000 r/min的试验条件下,对SVD得到的第2个模态进行3层小波包分解后,第2个节点的重心频率在阈值为95 kHz时能够可靠识别裂纹转子。 展开更多
关键词 声发射(AE) 奇异值分解(svd) 正交模态 重心频率 助力转向泵 裂纹转子
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Fault diagnosis for gearboxes based on Fourier decomposition method and resonance demodulation 被引量:4
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作者 Shuiguang TONG Zilong FU +2 位作者 Zheming TONG Junjie LI Feiyun CONG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2023年第5期404-418,共15页
Condition monitoring and fault diagnosis of gearboxes play an important role in the maintenance of mechanical systems.The vibration signal of gearboxes is characterized by complex spectral structure and strong time va... Condition monitoring and fault diagnosis of gearboxes play an important role in the maintenance of mechanical systems.The vibration signal of gearboxes is characterized by complex spectral structure and strong time variability,which brings challenges to fault feature extraction.To address this issue,a new demodulation technique,based on the Fourier decomposition method and resonance demodulation,is proposed to extract fault-related information.First,the Fourier decomposition method decomposes the vibration signal into Fourier intrinsic band functions(FIBFs)adaptively in the frequency domain.Then,the original signal is segmented into short-time vectors to construct double-row matrices and the maximum singular value ratio method is employed to estimate the resonance frequency.Then,the resonance frequency is used as a criterion to guide the selection of the most relevant FIBF for demodulation analysis.Finally,for the optimal FIBF,envelope demodulation is conducted to identify the fault characteristic frequency.The main contributions are that the proposed method describes how to obtain the resonance frequency effectively and how to select the optimal FIBF after decomposition in order to extract the fault characteristic frequency.Both numerical and experimental studies are conducted to investigate the performance of the proposed method.It is demonstrated that the proposed method can effectively demodulate the fault information from the original signal. 展开更多
关键词 Fourier decomposition method singular value ratio Resonance frequency Envelope demodulation Fault diagnosis
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一种基于LWT-DCT-SVD抗压缩的图像水印方案
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作者 杨志疆 《肇庆学院学报》 2025年第2期69-74,共6页
针对图像水印的透明性和鲁棒性的矛盾问题,以及图像水印在图像压缩攻击中鲁棒性较差的问题,提出基于LWT-DCT-SVD混合域的抗压缩鲁棒性图像水印方案.该方案应用混沌序列和置乱变换加密水印,提高水印的安全性,并选取LWT-DCT变换的低频系... 针对图像水印的透明性和鲁棒性的矛盾问题,以及图像水印在图像压缩攻击中鲁棒性较差的问题,提出基于LWT-DCT-SVD混合域的抗压缩鲁棒性图像水印方案.该方案应用混沌序列和置乱变换加密水印,提高水印的安全性,并选取LWT-DCT变换的低频系数进行SVD变换,并在奇异值中采用自适应量化嵌入水印,实现盲检测.仿真实验结果表明,水印保持较好的透明性,同时在噪声污染、低通滤波、图像缩放、恶意剪切等常见图像处理具有较强的鲁棒性,尤其对于图像压缩攻击,本水印方案显示出较强的抗压缩特征. 展开更多
关键词 提升小波变换 离散余弦变换 奇异值分解 抗压缩 鲁棒性
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应用奇异值分解(SVD)-主成分分析(PCA)组合模型定量圈定与评价腾冲地块锡钨和铅锌多金属找矿靶区 被引量:4
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作者 郑澳月 费金娜 +3 位作者 陈永清 宁妍云 曹一琳 赵鹏大 《地学前缘》 北大核心 2025年第1期283-301,共19页
成矿元素或元素组在一个地质单元中的富集是成岩和成矿地质过程多阶段作用的产物。基于水系沉积物地球化学数据,主成分分析(principal component analysis,PCA)可识别成矿元素组。奇异值分解(singular value decomposition,SVD)可将成... 成矿元素或元素组在一个地质单元中的富集是成岩和成矿地质过程多阶段作用的产物。基于水系沉积物地球化学数据,主成分分析(principal component analysis,PCA)可识别成矿元素组。奇异值分解(singular value decomposition,SVD)可将成矿元素组主成分得分进一步分解为两个部分:(1)成矿元素组合区域异常分量,能够表征在地壳演化过程中,由各种地质作用(岩浆作用、沉积作用和/或变质作用)形成的有利于成矿的高背景区域;(2)成矿元素组合局部异常分量,能够表征成矿作用引起的,叠加在成矿元素组合区域异常分量之上的成矿元素组合局部异常分量,应用局部异常分量能够识别找矿靶区。本次研究,首先基于国家1∶200000水系沉积物地球化学数据,应用主成分分析建立不同类型的成矿元素组;其次,利用SVD从成矿元素组的主成分得分中识别出不同类型成矿过程引起的成矿元素组合局部异常分量;最后,应用局部异常分量识别找矿靶区。最终在腾冲地块圈定15处找矿靶区,其中Sn-W找矿靶区8处,Pb-Zn-Ag找矿靶区7处。预测Sn-W潜在资源量915 Mt,Pb-Zn-Ag潜在资源量792 Mt。 展开更多
关键词 svd PCA 成矿元素组合异常分量 地球化学块体 锡钨和铅锌多金属矿 腾冲地块 西南地区
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SVD-MPE: An SVD-Based Vector Extrapolation Method of Polynomial Type 被引量:1
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作者 Avram Sidi 《Applied Mathematics》 2016年第11期1260-1278,共20页
An important problem that arises in different areas of science and engineering is that of computing the limits of sequences of vectors , where , N being very large. Such sequences arise, for example, in the solution o... An important problem that arises in different areas of science and engineering is that of computing the limits of sequences of vectors , where , N being very large. Such sequences arise, for example, in the solution of systems of linear or nonlinear equations by fixed-point iterative methods, and are simply the required solutions. In most cases of interest, however, these sequences converge to their limits extremely slowly. One practical way to make the sequences converge more quickly is to apply to them vector extrapolation methods. Two types of methods exist in the literature: polynomial type methods and epsilon algorithms. In most applications, the polynomial type methods have proved to be superior convergence accelerators. Three polynomial type methods are known, and these are the minimal polynomial extrapolation (MPE), the reduced rank extrapolation (RRE), and the modified minimal polynomial extrapolation (MMPE). In this work, we develop yet another polynomial type method, which is based on the singular value decomposition, as well as the ideas that lead to MPE. We denote this new method by SVD-MPE. We also design a numerically stable algorithm for its implementation, whose computational cost and storage requirements are minimal. Finally, we illustrate the use of SVD-MPE with numerical examples. 展开更多
关键词 Vector Extrapolation Minimal Polynomial Extrapolation singular value decomposition Krylov Subspace methods
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基于TFG-SVD-1DCNN的液压优先阀智能故障诊断方法 被引量:1
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作者 何瑶 熊晓燕 +2 位作者 王伟杰 李翔宇 刘会军 《机电工程》 北大核心 2025年第7期1287-1293,共7页
液压优先阀连接在液压泵、蓄能器和油箱增压腔之间,针对其容易受到多路干扰的影响,以及采用传统的液压测试方法对优先阀故障识别精度不足的问题,提出了一种基于时频图结构数据奇异值分解与一维卷积神经网络(TFG-SVD-1DCNN)的液压阀智能... 液压优先阀连接在液压泵、蓄能器和油箱增压腔之间,针对其容易受到多路干扰的影响,以及采用传统的液压测试方法对优先阀故障识别精度不足的问题,提出了一种基于时频图结构数据奇异值分解与一维卷积神经网络(TFG-SVD-1DCNN)的液压阀智能故障诊断方法。首先,采用短时傅里叶变换(STFT)的方法分析了包含故障信息的信号,提取了信号在不同时间段内频率成分的详细信息,得到了时频矩阵;然后,使用时频矩阵在频率维度上的特征构造了图结构数据(GSD),获得了边的连接关系和边的权重等信息,再利用这些信息生成了图结构数据的邻接矩阵,充分保留了每个样本的空间特征;最后,采用奇异值分解(SVD)方法对图结构数据的邻接矩阵进行了降维,将降维之后的主要特征输入到一维卷积神经网络(1D-CNN)中进行了故障分类,并利用仿真数据验证了该方法在优先阀故障诊断方面的性能。研究结果表明:对于优先阀正向无法打开或关断以及反向无法打开或关断4种故障类型,采用智能故障诊断方法所得的平均准确率为99.7%。该研究可以为液压阀故障检测提供一种有效的方法。 展开更多
关键词 液压系统 液压阀 流量优先阀 时频图结构数据奇异值分解 一维卷积神经网络 短时傅里叶变换 图结构数据
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On the Application of Adomian Decomposition Method to Special Equations in Physical Sciences
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作者 Aishah Alsulami Mariam Al-Mazmumy +1 位作者 Huda Bakodah Nawal Alzaid 《American Journal of Computational Mathematics》 2023年第3期387-397,共11页
The current manuscript makes use of the prominent iterative procedure, called the Adomian Decomposition Method (ADM), to tackle some important special differential equations. The equations of curiosity in this study a... The current manuscript makes use of the prominent iterative procedure, called the Adomian Decomposition Method (ADM), to tackle some important special differential equations. The equations of curiosity in this study are the singular equations that arise in many physical science applications. Thus, through the application of the ADM, a generalized recursive scheme was successfully derived and further utilized to obtain closed-form solutions for the models under consideration. The method is, indeed, fascinating as respective exact analytical solutions are accurately acquired with only a small number of iterations. 展开更多
关键词 Iterative Scheme Adomian decomposition method Initial-value Problems singular Ordinary Differential Equations
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基于ITD和SVD的振动信号特征提取
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作者 武鹏 于明月 《航空发动机》 北大核心 2025年第6期94-100,共7页
针对在含有大量气动噪声和结构噪声的机匣振动信号中提取故障特征的航空发动机轴承故障诊断的关键问题,提出一种基于本征时间尺度分解(ITD)和奇异值分解(SVD)相结合的故障诊断方法。通过对在发动机外机匣测得的时域振动信号进行ITD预处... 针对在含有大量气动噪声和结构噪声的机匣振动信号中提取故障特征的航空发动机轴承故障诊断的关键问题,提出一种基于本征时间尺度分解(ITD)和奇异值分解(SVD)相结合的故障诊断方法。通过对在发动机外机匣测得的时域振动信号进行ITD预处理,获取了对应的固有旋转(PR)分量,实现了振动信号中包含的故障特征的凸显;对各分量信号的时域信号通过系统延迟法构建Hankel矩阵,并基于奇异值分解的奇异值差分谱方法进行降噪,以滤除噪声干扰,提取相对微弱的故障特征信息;选取包含故障信息丰富的降噪后的PR分量用于信号重构,通过希尔伯特包络解调谱对重构信号进行特征提取,用于识别故障类型。将此方法用于航空发动机轴承故障诊断,验证了其有效性。 展开更多
关键词 本征时间尺度分解 HANKEL矩阵 奇异值分解 希尔伯特包络解调谱 故障诊断
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基于C-SVD降维的改进FCM负荷聚类方法
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作者 万进维 邢洁 +2 位作者 单英浩 金贝芋 侯美倩 《电力科学与技术学报》 北大核心 2025年第5期90-97,共8页
日负荷数据聚类是实现用户用电特性分析的重要方式。用于聚类的降维采样数据的指标权重会影响聚类结果,因此提出一种基于CRITIC赋权的奇异值分解(singular value decomposition,SVD)降维方法C-SVD与改进加权模糊C均值聚类(fuzzy C-means... 日负荷数据聚类是实现用户用电特性分析的重要方式。用于聚类的降维采样数据的指标权重会影响聚类结果,因此提出一种基于CRITIC赋权的奇异值分解(singular value decomposition,SVD)降维方法C-SVD与改进加权模糊C均值聚类(fuzzy C-means,FCM)算法相结合的日负荷数据聚类方法,同时针对传统FCM易受初始聚类中心影响的问题,提出一种自适应确定初始聚类中心的密度‒距离中心点选择(density-distance centersr selection,DDCS)方法。首先,采用SVD对负荷数据进行降维处理;其次,使用CRITIC赋权法对降维指标进行权重配置;然后,使用DDCS法确定初始聚类中心;最后,使用加权FCM算法对负荷数据进行聚类。仿真算例表明,与传统方法相比,所提方法鲁棒性强,能够明显提升负荷数据聚类结果的准确性。 展开更多
关键词 日负荷数据 CRITIC赋权法 奇异值分解 加权FCM聚类 聚类中心选取
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