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基于特征子阵匹配的织物组织分析 被引量:4
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作者 袁惠芬 王旭 《纺织学报》 EI CAS CSCD 北大核心 2009年第9期45-48,54,共5页
为能在仿制设计过程中快速且简便地提取待分析织物的完全组织循环参数,提出一种基于特征子阵匹配的织物组织分析方法。根据织物分析得到的意匠图,建立相应的组织矩阵。通过一维搜索方法分别找出组织矩阵经、纬向可能的循环,并以此建立... 为能在仿制设计过程中快速且简便地提取待分析织物的完全组织循环参数,提出一种基于特征子阵匹配的织物组织分析方法。根据织物分析得到的意匠图,建立相应的组织矩阵。通过一维搜索方法分别找出组织矩阵经、纬向可能的循环,并以此建立特征子阵。分别对特征子阵进行二维铺设,根据铺设结果和组织矩阵是否匹配,判定特征子阵是否为完全组织。研究表明:分析完全组织循环数大的织物时,一维搜索的方法可以优化特征子阵的寻找和选择;通过对特征子阵的铺设并和原始意匠图的匹配,可以实现完全组织循环参数的提取。 展开更多
关键词 织物组织 组织矩 特征 变换
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宽带子阵域特征空间稳健对角减载波束形成 被引量:1
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作者 王昊 马启明 《电子学报》 EI CAS CSCD 北大核心 2019年第3期584-590,共7页
针对宽带子阵域自适应波束形成器在实际使用中稳健性下降、对弱信号的检测能力受信噪比限制的问题,提出了一种宽带子阵域特征空间稳健对角减载自适应波束形成方法.首先提出利用子阵域特征空间投影法修正导引向量并得到球形不确定集的估... 针对宽带子阵域自适应波束形成器在实际使用中稳健性下降、对弱信号的检测能力受信噪比限制的问题,提出了一种宽带子阵域特征空间稳健对角减载自适应波束形成方法.首先提出利用子阵域特征空间投影法修正导引向量并得到球形不确定集的估计,再利用RCB(Robust Capon Beamformer)算法得到约束条件下的最优权值.另一方面,利用子阵域互谱密度矩阵的最小特征值作为子阵域非相关噪声功率的估计并进行对角减载,以最优权值对减载矩阵波束形成得到子带波束输出,对每个窄子带重复上述处理,再将结果非相干叠加即可得到本文方法的最终结果.理论及实验分析表明方法能提高自适应波束形成器的稳健性及输出信噪比. 展开更多
关键词 信号与信息处理 宽带稳健自适应波束形成 特征空间 对角减载
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火箭深弹弹阵特征计算模型和分析
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作者 冀志轩 成赫鹏 朱朝峰 《装备制造技术》 2015年第5期33-37,共5页
通过建立六联装舰载火箭深弹弹着点计算模型,对单座和双座火箭深弹弹着点的特征进行了分析。在考虑首摇、纵摇、横摇、纵荡、横荡、垂荡等运动及扰动的情况下,分别对单座和双座六联装火箭深弹的弹着点坐标进行了仿真计算;研究了弹着点... 通过建立六联装舰载火箭深弹弹着点计算模型,对单座和双座火箭深弹弹着点的特征进行了分析。在考虑首摇、纵摇、横摇、纵荡、横荡、垂荡等运动及扰动的情况下,分别对单座和双座六联装火箭深弹的弹着点坐标进行了仿真计算;研究了弹着点的统计分布规律;拟合出双座火箭深弹散布区域表达式和弹着点的联合密度函数。对比分析了单座和双座火箭发射器弹着点的特征的差异。结果表明,单座和双座发射器弹着点散布区域均呈椭圆形分布,由于发射参数的正态扰动,弹着点坐标均仍服从正态分布。 展开更多
关键词 火箭深弹 特征 正态分布 联合密度函数
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基于x-LMS算法的直升机主动消振电力作动器系统研究
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作者 郝振洋 杨健 +2 位作者 张嘉文 曹鑫 王涛 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第1期53-65,共13页
直升机前飞时,气动环境会导致不同方位角的桨叶出现气动载荷的瞬间不对称,通过基础结构传递会在机身形成大幅度的低频振动。为了消除多方向幅值变化的振动力,利用结构响应主动控制原理,设计了基于x-LMS算法的主动消振电力作动器系统,并... 直升机前飞时,气动环境会导致不同方位角的桨叶出现气动载荷的瞬间不对称,通过基础结构传递会在机身形成大幅度的低频振动。为了消除多方向幅值变化的振动力,利用结构响应主动控制原理,设计了基于x-LMS算法的主动消振电力作动器系统,并进行了减振实验。首先,通过比较确定了单台作动器中两台电机同向旋转的方案。通过两台作动器的组合使用,推导出输出力的数学模型。其次,采用负载相位差交叉耦合的控制策略设计系统控制框图。针对存在耦合的相位外环,通过回差阵特征值法确定满足系统稳定裕度要求的参数范围,再根据灵敏度函数和输入跟踪性能在所得的参数稳定域内寻找最优解。然后,提出了基于x-LMS算法的直升机主动振动控制系统,并通过仿真验证了该系统的减振效果。最后,研制的实验样机进行了动稳态实验以及减振实验,验证了系统的实际减振效果。 展开更多
关键词 结构响应主动控制 消振电力作动器 回差特征值法 x-LMS算法
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基于广义S变换的电压骤降特征量检测方法 被引量:15
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作者 唐求 滕召胜 郭斯羽 《电子测量与仪器学报》 CSCD 2012年第2期113-119,共7页
为实现电压骤降信号特征量的准确检测,提出并建立了基于广义S变换的电压骤降特征量检测方法。介绍了广义S变换的基本原理,构建了电压骤降特征量的计算模型,给出了电压骤降特征参数的检测流程。对离散电压信号进行广义S变换,通过广义S变... 为实现电压骤降信号特征量的准确检测,提出并建立了基于广义S变换的电压骤降特征量检测方法。介绍了广义S变换的基本原理,构建了电压骤降特征量的计算模型,给出了电压骤降特征参数的检测流程。对离散电压信号进行广义S变换,通过广义S变换的基波幅值曲线计算电压骤降幅值;由广义S变换的高频频谱幅值和曲线得到电压骤降起始、结束时刻和电压骤降持续时间;利用广义S矩阵的相位矩阵计算得到电压骤降相位跳变值。仿真实验验证了方法的准确性。与现有检测方法相比,基于广义S变换的电压骤降特征量检测方法计算量小,准确度高,抑制噪声干扰与谐波影响效果好。 展开更多
关键词 电压骤降:广义S变换:特征量:幅佰锸:相付铝
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化方阵为相似对角阵的一个判别条件
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作者 姜晓艳 《辽宁师专学报(自然科学版)》 2004年第2期2-2,29,共2页
讨论了复数域上n阶方阵A可化成相似对角阵的一个充要条件 ,该条件容易计算 ,比线性代数中其它的判别条件更直接。
关键词 相似对角 判别条件 复数域 特征多项式 最小多项式 特征阵
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Study on Extracting Information about Settlements Distribution in Western Jilin Province Based on Decision Tree Model 被引量:1
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作者 连懿 陈圣波 +1 位作者 王亚楠 逄超 《Journal of Landscape Research》 2010年第2期92-95,共4页
With western Jilin Province as the study region, spectral characteristics and texture features of remote sensing images were taken as the classification basis to construct a Decision Tree Model and extract information... With western Jilin Province as the study region, spectral characteristics and texture features of remote sensing images were taken as the classification basis to construct a Decision Tree Model and extract information about settlements in western Jilin Province, and the manually-extracted information about settlements in western Jilin Province was evaluated by confusion matrix. The results showed that Decision Tree Model was convenient for extracting settlements information by integrating spectral and texture features, and the accuracy of such a method was higher than that of the traditional Maximum Liklihood Method, in addition, calculation methods of extracting settlements information by this mean were concluded. 展开更多
关键词 SETTLEMENTS TM Western Jilin Province Spectral characteristics Texture features Decision Tree Confusion matrix
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The Distribution of Eigenvance of Product Diagonal Dominance Matrix 被引量:1
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作者 杨益民 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第3期32-40,共9页
Let DD_0(R)={A∈C^(n×#)||Rea_(ii)Rea_(jj)|≥A_iA_j,i≠j,i,j∈N}.PD_0(R)={A∈C^(n×#)||Rea_(ii)Rea_(kk)|≥A_iA_jA_k,i≠j≠k,i,j,k∈N}. In this paper,we show DD_0(R)PD_0(R),and the conditions under which the nu... Let DD_0(R)={A∈C^(n×#)||Rea_(ii)Rea_(jj)|≥A_iA_j,i≠j,i,j∈N}.PD_0(R)={A∈C^(n×#)||Rea_(ii)Rea_(kk)|≥A_iA_jA_k,i≠j≠k,i,j,k∈N}. In this paper,we show DD_0(R)PD_0(R),and the conditions under which the numbers of eigen vance of A∈PD_0(R)\DD_0(R)are equal to the numbers of a_(ii),i∈N in positive and negative real part respectively.Some couter examples are given which present the condnions can not be omitted. 展开更多
关键词 MATRIX diagonal dominance EIGENVALUE DISTRIBUTION
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A Decorrelating DOA Estimation Based on the Principal Eigenvector for CDMA Frequency-Selective Fading Channels
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作者 杨维 蒋朱成 程时昕 《Journal of Southeast University(English Edition)》 EI CAS 2001年第2期14-17,共4页
A novel decorrelating DOA estimation algorithm of multipath signals for CDMA frequency selective fading channels based only on the principal eigenvector of its corresponding covariance matrix is proposed. The propose... A novel decorrelating DOA estimation algorithm of multipath signals for CDMA frequency selective fading channels based only on the principal eigenvector of its corresponding covariance matrix is proposed. The proposed algorithm has the advantages that the DOAs of the multipath signals can be estimated independently and all the other resolved multipath signal interference is eliminated. Simulation results show that this algorithm estimates the DOAs of multipath signals efficiently and accurately. 展开更多
关键词 decorrelating DOA estimation antenna array CDMA system EIGENVECTOR
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基于配电线路三相电流同步检测的故障定位方法
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作者 于朝辉 《电力系统装备》 2020年第11期140-141,200,共3页
文章结合配电网PMU三相电流同步检测技术发展与应用,提出基于电流特征阵F-范数的自适应故障区段定位算法,在PSCAD软件中搭建IEEE34节点经典算例模型对算法进行验证。结果表明,所提故障定位算法在含高比例分布式电源的配电网中能够精准... 文章结合配电网PMU三相电流同步检测技术发展与应用,提出基于电流特征阵F-范数的自适应故障区段定位算法,在PSCAD软件中搭建IEEE34节点经典算例模型对算法进行验证。结果表明,所提故障定位算法在含高比例分布式电源的配电网中能够精准定位故障区段。 展开更多
关键词 配电网 三相电流 同步检测 电流特征阵
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BEST APPROXIMATION BY NORMAL MATRICES WITH SPECTRAL CONSTRAINTS
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作者 戴华 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1998年第2期88-92,共5页
The problem of best approximating, a given square complex matrix in the Frobenius norm by normal matrices under a given spectral restriction is considered. The ne cessary and sufficient condition for the solvability ... The problem of best approximating, a given square complex matrix in the Frobenius norm by normal matrices under a given spectral restriction is considered. The ne cessary and sufficient condition for the solvability of the problem is given. A numerical algorithm for solving the problem is provided and a numerical example is presented. 展开更多
关键词 normal matrices best approximation EIGENVALUES inverse problems spectral constraint
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A method of automatic plane detection without random search
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作者 李中科 杨晓辉 吴乐南 《Journal of Southeast University(English Edition)》 EI CAS 2003年第3期216-220,共5页
Plane detection is a prerequisite for many computer vision tasks. This paper proposes a new method which can automatically detect planes from two projective images. Firstly, we modify Scott’s feature point matching m... Plane detection is a prerequisite for many computer vision tasks. This paper proposes a new method which can automatically detect planes from two projective images. Firstly, we modify Scott’s feature point matching method by post-processing its result with the concept of similarity, and then get the lines matching according to feature points matching based on the approximate invariance of the features’ distribution between two images. Finally, we group all feature points into subsets in terms of their geometric relations with feature lines as initial sets to estimate homography rather than by a random search strategy (like RANSAC) as in most existing methods. The proposed method is especially suitable to detecting planes in man-made scenes. This method is validated on real images. 展开更多
关键词 plane detection feature matching plane homography computer vision
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A Robust Collaborative Recommendation Algorithm Based on k-distance and Tukey M-estimator 被引量:6
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作者 YI Huawei ZHANG Fuzhi LAN Jie 《China Communications》 SCIE CSCD 2014年第9期112-123,共12页
The existing collaborative recommendation algorithms have lower robustness against shilling attacks.With this problem in mind,in this paper we propose a robust collaborative recommendation algorithm based on k-distanc... The existing collaborative recommendation algorithms have lower robustness against shilling attacks.With this problem in mind,in this paper we propose a robust collaborative recommendation algorithm based on k-distance and Tukey M-estimator.Firstly,we propose a k-distancebased method to compute user suspicion degree(USD).The reliable neighbor model can be constructed through incorporating the user suspicion degree into user neighbor model.The influence of attack profiles on the recommendation results is reduced through adjusting similarities among users.Then,Tukey M-estimator is introduced to construct robust matrix factorization model,which can realize the robust estimation of user feature matrix and item feature matrix and reduce the influence of attack profiles on item feature matrix.Finally,a robust collaborative recommendation algorithm is devised by combining the reliable neighbor model and robust matrix factorization model.Experimental results show that the proposed algorithm outperforms the existing methods in terms of both recommendation accuracy and robustness. 展开更多
关键词 shilling attacks robust collaborative recommendation matrix factori-zation k-distance Tukey M-estimator
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A novel shapelet transformation method for classification of multivariate time series with dynamic discriminative subsequence and application in anode current signals 被引量:3
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作者 WAN Xiao-xue CHEN Xiao-fang +2 位作者 GUI Wei-hua YUE Wei-chao XIE Yong-fang 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第1期114-131,共18页
Classification of multi-dimension time series(MTS) plays an important role in knowledge discovery of time series. Many methods for MTS classification have been presented. However, most of these methods did not conside... Classification of multi-dimension time series(MTS) plays an important role in knowledge discovery of time series. Many methods for MTS classification have been presented. However, most of these methods did not consider the kind of MTS whose discriminative subsequence was not restricted to one dimension and dynamic. In order to solve the above problem, a method to extract new features with extended shapelet transformation is proposed in this study. First, key features is extracted to replace k shapelets to calculate distance, which are extracted from candidate shapelets with one class for all dimensions. Second, feature of similarity numbers as a new feature is proposed to enhance the reliability of classification. Third, because of the time-consuming searching and clustering of shapelets, distance matrix is used to reduce the computing complexity. Experiments are carried out on public dataset and the results illustrate the effectiveness of the proposed method. Moreover, anode current signals(ACS) in the aluminum reduction cell are the aforementioned MTS, and the proposed method is successfully applied to the classification of ACS. 展开更多
关键词 anode current signals key features distance matrix feature of similarity numbers shapelet transformation
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The Explicit Expressions of Level- k(r1 ,r2 ,… ,rk) Circulant Matrices and Their Some Properties 被引量:3
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作者 江兆林 叶留青 邓方安 《Chinese Quarterly Journal of Mathematics》 CSCD 1998年第2期91-96, ,共6页
In this paper,we give the explicit expressions of level k (r 1,r 2,…,r k) circulant matrices of order n 1n 2…n k,and the explicit expressions for the eigenvalues,the determinants and the inverse matrices of the kind... In this paper,we give the explicit expressions of level k (r 1,r 2,…,r k) circulant matrices of order n 1n 2…n k,and the explicit expressions for the eigenvalues,the determinants and the inverse matrices of the kind level k (r 1,r 2,…,r k) circulant matrices are derived,and it is also proved that the sort of matrices are diagonalizable. 展开更多
关键词 level-k (r 1 r 2 r k) circulant matrices explicit expressions EIGENVALUES inverse matrices
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Identification of indoor multi-component pollution gas aliasing peak based on JADE
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作者 王芳 李晋华 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第1期24-29,共6页
Monitoring indoor harmful gas can obtain the infrared spectra of mixed harmful gases.Since the absorption bands of mixed gases overlap and their qualitative and quantitative analyses are not easy,feature extraction me... Monitoring indoor harmful gas can obtain the infrared spectra of mixed harmful gases.Since the absorption bands of mixed gases overlap and their qualitative and quantitative analyses are not easy,feature extraction method based on joint approximative diagonalization of eigenmatrix(JADE)is proposed.By fully mining the hidden information of original data and analyzing higher-order statistics information of the data,each substance spectrum in the mixed gas can be accurately distinguished.In addition,a multi-dimensional data quantitative analysis model of the extracted independent source is established by using support vector machine(SVM)based on regular theory.The experimental results show that the correlation coefficients of the components of mixed gases is above 0.999 1by quantitative analysis,which verifies the accuracy of this feature extraction method. 展开更多
关键词 aliasing peak identification joint approximative diagonalization of eigenmatrix(JADE) quantitative analysis sup-port vector machine(SVM)
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The Explicit Expressions of Level-k Circulant Matrices of Type(n_1,n_2.…,n_k) and Their Some Properties 被引量:2
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作者 江兆林 郭运瑞 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第3期103-110,共8页
In this paper, we give the explicit expressions of level-k circulant matrices of type (n1,n2,…nk) and of order n1n2…nk,and the explicit expressions for the eigenvalues,the determinants and the inverse matrices of th... In this paper, we give the explicit expressions of level-k circulant matrices of type (n1,n2,…nk) and of order n1n2…nk,and the explicit expressions for the eigenvalues,the determinants and the inverse matrices of the kind level-k circulant matrices are derived,and it is also proved that the sort matrices are unitarily diagonalizable. 展开更多
关键词 level-k circulant matrices of type (n1 n2 nk) explicit expressions eigenvalues determinants inverse matrices unitarily diagonalizable
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Computation of Jordan Chains by Generalized Characteristic Matrices 被引量:1
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作者 LI Da-lin 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第1期58-62,共5页
In this paper, we introduce a method to define generalized characteristic matrices of a defective matrix by the common form of Jordan chains. The generalized characteristic matrices can be obtained by solving a system... In this paper, we introduce a method to define generalized characteristic matrices of a defective matrix by the common form of Jordan chains. The generalized characteristic matrices can be obtained by solving a system of linear equations and they can be used to compute Jordan basis. 展开更多
关键词 Jordan canonical form Jordan chain generalized characteristic matrix char-acteristic polynomial
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Nonsingularity on Level-2(r_1, r_2)-circulant Matrices of Type (m,n) 被引量:5
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作者 江兆林 郭运端 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第2期106-110,共5页
In this pape,we give four methods of discriminations its nonsingularity by utilizing only parametr r1,r2 and elements of the first row of level-2 (r1, r2)-circulant matrices of type (m,n).
关键词 level-2(r_1 r_2)-circulant matrices of type (m n) nonsingularit
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Novel histogram descriptor for global feature extraction and description 被引量:3
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作者 张刚 马宗民 +1 位作者 邓立国 徐长明 《Journal of Central South University》 SCIE EI CAS 2010年第3期580-586,共7页
A novel histogram descriptor for global feature extraction and description was presented. Three elementary primitives for a 2×2 pixel grid were defined. The complex primitives were computed by matrix transforms. ... A novel histogram descriptor for global feature extraction and description was presented. Three elementary primitives for a 2×2 pixel grid were defined. The complex primitives were computed by matrix transforms. These primitives and equivalence class were used for an image to compute the feature image that consisted of three elementary primitives. Histogram was used for the transformed image to extract and describe the features. Furthermore, comparisons were made among the novel histogram descriptor, the gray histogram and the edge histogram with regard to feature vector dimension and retrieval performance. The experimental results show that the novel histogram can not only reduce the effect of noise and illumination change, but also compute the feature vector of lower dimension. Furthermore, the system using the novel histogram has better retrieval performance. 展开更多
关键词 feature extraction and description histogram descriptor gray histogram edge histogram
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