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Obtaining Profiles Based on Localized Non-negative Matrix Factorization 被引量:2
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作者 JIANGJi-xiang XUBao-wen +1 位作者 LUJian-jiang ZhouXiao-yu 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第5期580-584,共5页
Nonnegative matrix factorization (NMF) is a method to get parts-based features of information and form the typical profiles. But the basis vectors NMF gets are not orthogonal so that parts-based features of informatio... Nonnegative matrix factorization (NMF) is a method to get parts-based features of information and form the typical profiles. But the basis vectors NMF gets are not orthogonal so that parts-based features of information are usually redundancy. In this paper, we propose two different approaches based on localized non-negative matrix factorization (LNMF) to obtain the typical user session profiles and typical semantic profiles of junk mails. The LNMF get basis vectors as orthogonal as possible so that it can get accurate profiles. The experiments show that the approach based on LNMF can obtain better profiles than the approach based on NMF. Key words localized non-negative matrix factorization - profile - log mining - mail filtering CLC number TP 391 Foundation item: Supported by the National Natural Science Foundation of China (60373066, 60303024), National Grand Fundamental Research 973 Program of China (2002CB312000), National Research Foundation for the Doctoral Program of Higher Education of China (20020286004).Biography: Jiang Ji-xiang (1980-), male, Master candidate, research direction: data mining, knowledge representation on the Web. 展开更多
关键词 localized non-negative matrix factorization PROFILE log mining mail filtering
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Using position specific scoring matrix and auto covariance to predict protein subnuclear localization 被引量:2
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作者 Rong-Quan Xiao Yan-Zhi Guo +4 位作者 Yu-Hong Zeng Hai-Feng Tan Hai-Feng Tan Xue-Mei Pu Meng-Long Li 《Journal of Biomedical Science and Engineering》 2009年第1期51-56,共6页
The knowledge of subnuclear localization in eukaryotic cells is indispensable for under-standing the biological function of nucleus, genome regulation and drug discovery. In this study, a new feature representation wa... The knowledge of subnuclear localization in eukaryotic cells is indispensable for under-standing the biological function of nucleus, genome regulation and drug discovery. In this study, a new feature representation was pro-posed by combining position specific scoring matrix (PSSM) and auto covariance (AC). The AC variables describe the neighboring effect between two amino acids, so that they incorpo-rate the sequence-order information;PSSM de-scribes the information of biological evolution of proteins. Based on this new descriptor, a support vector machine (SVM) classifier was built to predict subnuclear localization. To evaluate the power of our predictor, the benchmark dataset that contains 714 proteins localized in nine subnuclear compartments was utilized. The total jackknife cross validation ac-curacy of our method is 76.5%, that is higher than those of the Nuc-PLoc (67.4%), the OET- KNN (55.6%), AAC based SVM (48.9%) and ProtLoc (36.6%). The prediction software used in this article and the details of the SVM parameters are freely available at http://chemlab.scu.edu.cn/ predict_SubNL/index.htm and the dataset used in our study is from Shen and Chou’s work by downloading at http://chou.med.harvard.edu/ bioinf/Nuc-PLoc/Data.htm. 展开更多
关键词 POSITION Specific SCORING matrix AUTO COVARIANCE Support Vector Machine Protein SUBNUCLEAR localization Prediction
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Impact vibration properties of locally resonant fluid-conveying pipes 被引量:2
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作者 Bing Hu Fu-Lei Zhu +4 位作者 Dian-Long Yu Jiang-Wei Liu Zhen-Fang Zhang Jie Zhong Ji-Hong Wen 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第12期313-321,共9页
Fluid-conveying pipe systems are widely used in various equipments to transport matter and energy.Due to the fluid–structure interaction effect,the fluid acting on the pipe wall is easy to produce strong vibration an... Fluid-conveying pipe systems are widely used in various equipments to transport matter and energy.Due to the fluid–structure interaction effect,the fluid acting on the pipe wall is easy to produce strong vibration and noise,which have a serious influence on the safety and concealment of the equipment.Based on the theory of phononic crystals,this paper studies the vibration transfer properties of a locally resonant(LR)pipe under the condition of fluid–structure interaction.The band structure and the vibration transfer properties of a finite periodic pipe are obtained by the transfer matrix method.Further,the different impact excitation and fluid–structure interaction effect on the frequency range of vibration attenuation properties of the LR pipe are mainly considered and calculated by the finite element model.The results show that the existence of a low-frequency vibration bandgap in the LR pipe can effectively suppress the vibration propagation under external impact and fluid impact excitation,and the vibration reduction frequency range is near the bandgap under the fluid–structure interaction effect.Finally,the pipe impact experiment was performed to verify the effective attenuation of the LR structure to the impact excitation,and to validate the finite element model.The research results provide a technical reference for the vibration control of the fluid-conveying pipe systems that need to consider blast load and fluid impact. 展开更多
关键词 locally resonant pipe fluid-structure interaction transfer matrix method impact vibration properties
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Sensing Matrix Optimization for Multi-Target Localization Using Compressed Sensing in Wireless Sensor Network 被引量:2
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作者 Xinhua Jiang Ning Li +2 位作者 Yan Guo Jie Liu Cong Wang 《China Communications》 SCIE CSCD 2022年第3期230-244,共15页
In the multi-target localization based on Compressed Sensing(CS),the sensing matrix's characteristic is significant to the localization accuracy.To improve the CS-based localization approach's performance,we p... In the multi-target localization based on Compressed Sensing(CS),the sensing matrix's characteristic is significant to the localization accuracy.To improve the CS-based localization approach's performance,we propose a sensing matrix optimization method in this paper,which considers the optimization under the guidance of the t%-averaged mutual coherence.First,we study sensing matrix optimization and model it as a constrained combinatorial optimization problem.Second,the t%-averaged mutual coherence is adopted as the optimality index to evaluate the quality of different sensing matrixes,where the threshold t is derived through the K-means clustering.With the settled optimality index,a hybrid metaheuristic algorithm named Genetic Algorithm-Tabu Local Search(GA-TLS)is proposed to address the combinatorial optimization problem to obtain the final optimized sensing matrix.Extensive simulation results reveal that the CS localization approaches using different recovery algorithms benefit from the proposed sensing matrix optimization method,with much less localization error compared to the traditional sensing matrix optimization methods. 展开更多
关键词 compressed sensing hybrid metaheuristic K-means clustering multi-target localization t%-averaged mutual coherence sensing matrix optimization
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Pseudopolarity of Generalized Matrix Rings over a Local Ring 被引量:1
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作者 Yin Xiao-bin Dou Wan Du Xian-kun 《Communications in Mathematical Research》 CSCD 2015年第3期211-221,共11页
Pseudopolar rings are closely related to strongly -regular rings, uniquelystrongly clean rings and semiregular rings. In this paper, we investigate pseudopolar-ity of generalized matrix rings Ks(R) over a local ring... Pseudopolar rings are closely related to strongly -regular rings, uniquelystrongly clean rings and semiregular rings. In this paper, we investigate pseudopolar-ity of generalized matrix rings Ks(R) over a local ring R. We determine the conditionsunder which elements of Ks(R) are pseudopolar. Assume that R is a local ring. It isshown that A ∈ Ks(R) is pseudopolar if and only if A is invertible or A^2 ∈ J(Ks(R))or A is similar to a diagonal matrix [ u 0 0 j ]; where lu -rj and lj-ru are injectiveand u 2 U(R) and j ∈ J(R). Furthermore, several equivalent conditions for Ks(R)over a local ring R to be pseudopolar are obtained. 展开更多
关键词 pseudopolar ring local ring generalized matrix ring
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ONSET CONDITION OF STRAIN LOCALIZATION IN MATRIX OF SATURATED POROUS MEDIA
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作者 赵纪生 陶夏新 +2 位作者 师黎静 欧进萍 LIN Jian-zhong 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第11期1475-1483,共9页
Based on governing equations of saturated porous media and Liapunov' s stability here, onset conditions matrix of porous media used by solid stress and Terzaghi's effective stress constitutive description under seep... Based on governing equations of saturated porous media and Liapunov' s stability here, onset conditions matrix of porous media used by solid stress and Terzaghi's effective stress constitutive description under seepage flow state, are presented, which have different forms with different representation of the solid phase, matrix or skeleton, constitutive model of porous media. The main difference relates with how to describe the interaction between solid phase and liquid phase in constitutive model. The derived onset condition of strain localization under Terzaghi' s effective stress description can be used to interpret different failure types, piping effect, landslides and mudflows, by means of the type and the magnitude ratio of relative movement between solid phase and liquid phase. Examples here illuminate the onset condition of how to work. 展开更多
关键词 porous medium solid stress Terzaghi's effective stress constitutive model of matrix onset condition of strain localization
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FLOCKING OF A THERMODYNAMIC CUCKER-SMALE MODEL WITH LOCAL VELOCITY INTERACTIONS
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作者 金春银 李双智 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期632-649,共18页
In this paper, we study the flocking behavior of a thermodynamic Cucker–Smale model with local velocity interactions. Using the spectral gap of a connected stochastic matrix, together with an elaborate estimate on pe... In this paper, we study the flocking behavior of a thermodynamic Cucker–Smale model with local velocity interactions. Using the spectral gap of a connected stochastic matrix, together with an elaborate estimate on perturbations of a linearized system, we provide a sufficient framework in terms of initial data and model parameters to guarantee flocking. Moreover, it is shown that the system achieves a consensus at an exponential rate. 展开更多
关键词 FLOCKING local interaction thermodynamical Cucker-Smale model stochastic matrix neighbor graph
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Data Matrix二维条形码解码器图像预处理研究 被引量:15
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作者 邹沿新 杨高波 《计算机工程与应用》 CSCD 北大核心 2009年第34期183-185,188,共4页
DM码是一种常见的二维条形码,图像预处理是DM码解码器自动识别过程中的重要步骤。提出一种实用的DM码识别图像预处理方法。它没有使用传统的边缘检测和直线检测手段,因此受背景噪声、几何失真的影响较小。此外,使用了校正铁路线坐标,并... DM码是一种常见的二维条形码,图像预处理是DM码解码器自动识别过程中的重要步骤。提出一种实用的DM码识别图像预处理方法。它没有使用传统的边缘检测和直线检测手段,因此受背景噪声、几何失真的影响较小。此外,使用了校正铁路线坐标,并按区域取样生成码流,显著提高了DM码的识别速度和识别率。实验结果表明,该算法可以克服DM码识别过程中易受噪声干扰、光照不均和几何失真等影响的问题。 展开更多
关键词 二维条形码 Data matrix 图像预处理 定位 二值化
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金属表面Data Matrix条码高光区域的信息重构 被引量:3
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作者 房欣欣 李建美 +2 位作者 路长厚 马卓 陶亮 《计算机工程与应用》 CSCD 北大核心 2016年第16期205-209,共5页
为实现工业产品的可追溯性,直接将条码加工在零件表面的直接零件标识(Direct Part Marking,DPM)技术,在国内外受到了越来越多的关注。对于金属零件,由于其具有较高的反光性,由相机捕获的金属表面的条码图像常常产生局部高光现象,影响条... 为实现工业产品的可追溯性,直接将条码加工在零件表面的直接零件标识(Direct Part Marking,DPM)技术,在国内外受到了越来越多的关注。对于金属零件,由于其具有较高的反光性,由相机捕获的金属表面的条码图像常常产生局部高光现象,影响条码的正确读取。为此,针对金属表面激光标刻二维条码出现的局部高光现象,提出了基于五步重构模型的条码重构法,以重构高光区域的条码信息。对获得的条码图像进行倾斜校正,使"L"型实线边界位于图像左下角,对条码进行网格划分实现各个模块的定位。基于Modified Specular-Free(MSF)图像对高光区域进行检测。采用五步重构模型对条码的各个模块进行数值填充,对条码进行读取。实验表明,该算法能达到去除金属表面上条码局部高光的目的,并取得了较高的识读正确率。 展开更多
关键词 直接零件标识 金属表面 DATA matrix条码 局部高光 重构
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Wave localization in randomly disordered periodic layered piezoelectric structures 被引量:11
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作者 Fengming Li Yuesheng Wang +1 位作者 Chao Hu Wenhu Huang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2006年第6期559-567,共9页
Considering the mechnoelectrical coupling, the localization of SH-waves in disordered periodic layered piezoelectric structures is studied. The waves propagating in directions normal and tangential to the layers are c... Considering the mechnoelectrical coupling, the localization of SH-waves in disordered periodic layered piezoelectric structures is studied. The waves propagating in directions normal and tangential to the layers are considered. The transfer matrices between two consecutive unit cells are obtained according to the continuity conditions. The expressions of localization factor and localization length in the disordered periodic structures are presented. For the disordered periodic piezoelectric structures, the numerical results of localization factor and localization length are presented and discussed. It can be seen from the results that the frequency passbands and stopbands appear for the ordered periodic structures and the wave localization phenomenon occurs in the disordered periodic ones, and the larger the coefficient of variation is, the greater the degree of wave localization is. The widths of stopbands in the ordered periodic structures are very narrow when the properties of the consecutive piezoelectric materials are similar and the intervals of stopbands become broader when a certain material parameter has large changes. For the wave propagating in the direction normal to the layers the localization length has less dependence on the frequency, but for the wave propagating in the direction tangential to the layers the localization length is strongly dependent on the frequency. 展开更多
关键词 Disordered periodic layered piezoelectric structures Transfer matrix Lyapunov exponent localization factor localization length
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Theoretical Investigations of the Local Structure Distortion and EPR Parameter for Ni2+-doped Perovskite Fluorides
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作者 曹喜民 邝小渝 +1 位作者 李成刚 柴瑞鹏 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第2期167-172,I0003,共7页
By analyzing the optical spectra and electron paramagnetic resonance parameter D, the local structure distortion of (NiF6)4- clusters in AMF3 (A=K, Rb; M=Zn, Cd, Ca) and K2ZnF4 series are studied using the complet... By analyzing the optical spectra and electron paramagnetic resonance parameter D, the local structure distortion of (NiF6)4- clusters in AMF3 (A=K, Rb; M=Zn, Cd, Ca) and K2ZnF4 series are studied using the complete energy matrix based on the double spin-orbit coupling parameter model for configuration ions in a tetragonal ligand field. The results indicate that the contribution of ligand to spin-orbit coupling interaction should be considered for our studied systems. Moreover, the relationships between D and the spin-obit coupling coefficients as well as the average parameter and the divergent parameter are discussed. 展开更多
关键词 Complete energy matrix Double spin-orbit coupling parameter model local structure distortion
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Wave propagation control in periodic track structure through local resonance mechanism 被引量:10
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作者 WANG Ping YI Qiang +2 位作者 ZHAO Cai-you XING Meng-ting LU J 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第12期3062-3074,共13页
Excessive vibration and noise radiation of the track structure can be caused by the operation of high speed trains.Though the track structure is characterized by obvious periodic properties and band gaps,the bandwidth... Excessive vibration and noise radiation of the track structure can be caused by the operation of high speed trains.Though the track structure is characterized by obvious periodic properties and band gaps,the bandwidth is narrow and the elastic wave attenuation capability within the band gap is weak.In order to effectively control the vibration and noise of track structure,the local resonance mechanism is introduced to broaden the band gap and realize wave propagation control.The locally resonant units are attached periodically on the rail,forming a new locally resonant phononic crystal structure.Then the tuning of the elastic wave band gaps of track structure is discussed,and the formation mechanism of the band gap is explicated.The research results show that a new wide and adjustable locally resonant band gap is formed after the resonant units are introduced.The phenomenon of coupling and transition can be observed between the new locally resonant band gap and the original band gap of the periodic track structure with the band gap width reaching the maximum at the coupling position.The broader band gap can be applied for vibration and noise reduction in high speed railway track structure. 展开更多
关键词 wave propagation control periodic track structure band gap local resonance mechanism transfer matrix
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One-Dimensional Localization of Elastic Waves in Rib-Stiffened Plates 被引量:1
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作者 李凤明 胡超 黄文虎 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2002年第4期208-212,共5页
The 1 dimensional localization of elastic waves in disordered periodic multi span rib stiffened plates is investigated. The transfer matrix method is employed to obtain the transfer matrix of the system, and the metho... The 1 dimensional localization of elastic waves in disordered periodic multi span rib stiffened plates is investigated. The transfer matrix method is employed to obtain the transfer matrix of the system, and the method for calculating the Lyapunov exponents in continuous dynamic systems presented by Wolf is used to determine the localization factor. As examples, the numerical results of the localization factors are given for a disordered rib stiffened plate. The effects of the degree of disorder of span... 展开更多
关键词 rib stiffened plate wave localization transfer matrix method Lyapunov exponent localization factor
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Uniquely strongly clean triangular matrix rings
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作者 崔建 陈建龙 《Journal of Southeast University(English Edition)》 EI CAS 2011年第4期463-465,共3页
An element a of a ring R is called uniquely strongly clean if it is the sum of an idempotent and a unit that commute, and in addition, this expression is unique. R is called uniquely strongly clean if every element of... An element a of a ring R is called uniquely strongly clean if it is the sum of an idempotent and a unit that commute, and in addition, this expression is unique. R is called uniquely strongly clean if every element of R is uniquely strongly clean. The uniquely strong cleanness of the triangular matrix ring is studied. Let R be a local ring. It is shown that any n × n upper triangular matrix ring over R is uniquely strongly clean if and only if R is uniquely bleached and R/J(R) ≈Z2. 展开更多
关键词 uniquely strongly clean ring uniquely bleached local ring triangular matrix ring
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The Experimental and Theoretical Research of "Local Resonance" in Ultrasonic Honing System 被引量:1
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作者 ZHU Xun-sheng, XU Ke-wei, ZHAO Bo, MA Deng-zhe (Mechanical School of Shanghai Jiaotong University, Shanghai 200030, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期49-,共1页
In 1982, Professor Fang Guoliang found the "Non full resonance" phenomenon in a tool system while he use the thin-long tool ultrasonically machining deep-small hole. He called it as "local resonance&quo... In 1982, Professor Fang Guoliang found the "Non full resonance" phenomenon in a tool system while he use the thin-long tool ultrasonically machining deep-small hole. He called it as "local resonance". Also this "Non full resonance" phenomenon was discovered in the ultrasonic drilling and the ultrasonic honing system later. To its mechanism, professor Fang thought that the coupling of long-thin tool bar and driving system is weak, so the tool bar can vibrate independently, but the quantitative relation between the coupling factor and diameter ratio is not made certain. Then several theories come forth to interpret it but still haven’t a common conclusion. Through the systematic experimental and theoretical research, this paper reveals that the "local resonance" phenomenon of ultrasonic honing system has the same essence with the "local resonance" phenomenon in deep hole machining system: when the section area ratio of tool bar and driving system is small enough, some resonance frequencies of combined system are close to the resonance frequencies of "fixed-free" state tool bar, the combined system is still resonant. According to the given depth of hole and structure size, we can use the transfer matrix deduced in this paper to design flexible bar and oilstone seat not only satisfying mechanical structure size but also achieving enough magnitude. It greatly simplified the design. This new method can be named as "local resonance" design method for ultrasonic honing system. The experiment, deduction and design method have a certain common meaning to the study and design of other ultrasonic system. 展开更多
关键词 local resonance ultrasonic honing system full resonance transfer matrix method
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WAVE LOCALIZATION IN RANDOMLY DISORDERED PERIODIC PIEZOELECTRIC RODS 被引量:9
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作者 Li Fengming Wang Yuesheng Chen Ali 《Acta Mechanica Solida Sinica》 SCIE EI 2006年第1期50-57,共8页
在周期、混乱的周期的压电的杆的波浪繁殖在这篇论文被学习。在二个连续单位房间之间的转移矩阵根据连续性条件被获得。压电的材料的机电的联合被考虑。根据矩阵特征值的理论,在周期的结构的频率乐队被学习。而且,由在两个介绍混乱尺... 在周期、混乱的周期的压电的杆的波浪繁殖在这篇论文被学习。在二个连续单位房间之间的转移矩阵根据连续性条件被获得。压电的材料的机电的联合被考虑。根据矩阵特征值的理论,在周期的结构的频率乐队被学习。而且,由在两个介绍混乱尺寸更少长度和压电的陶艺的有弹性的常数,在混乱周期的结构的波浪本地化被使用矩阵特征值方法和 Lyapunov 代表方法也学习。调节了周期的结构,这被发现让频率通带和站乐队和本地化现象能发生在错误调子周期的结构。由于压电的效果,而且,为不能通过结构宣传的波浪的频率区域稍微随压电的常数的增加被增加。 展开更多
关键词 周期压电杆 波局限化 转移矩阵 局限因子 无序状态
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Using Normal Form of Idempotent Matrices over Finite Local Ring Z/p^kZ to Construct Cartesian Authentication Codes 被引量:1
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作者 赵辉芳 南基洙 《Northeastern Mathematical Journal》 CSCD 2007年第2期123-131,共9页
In this paper, we determine the normal forms of idempotent matrices for similarity over finite local rings Z/p^kZ, from which we construct a Cartesian authentication code and compute its size parameters and the probab... In this paper, we determine the normal forms of idempotent matrices for similarity over finite local rings Z/p^kZ, from which we construct a Cartesian authentication code and compute its size parameters and the probabilities of successful impersonation and substitution attack under the hypothesis that the cecoding rules are chosen according to a uniform probability distribution. 展开更多
关键词 idempotent matrix finite local ring Cartesian authentication code
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Frequency Domain Filtering SAR Interferometric Phase Noise Using the Amended Matrix Pencil Model 被引量:1
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作者 Yandong Gao Shubi Zhang +1 位作者 Kefei Zhang Shijin Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2019年第5期349-363,共15页
Interferometric phase filtering is one of the key steps in interferometricsynthetic aperture radar (InSAR/SAR). However, the ideal filtering results are difficult toobtain due to dense fringe and low coherence regions... Interferometric phase filtering is one of the key steps in interferometricsynthetic aperture radar (InSAR/SAR). However, the ideal filtering results are difficult toobtain due to dense fringe and low coherence regions. Moreover, the InSAR/SAR datarange is relatively large, so the efficiency of interferential phase filtering is one of themajor problems. In this letter, we proposed an interferometric phase filtering methodbased on an amended matrix pencil and linear window mean filter. The combination ofthe matrix pencil and the linear mean filter are introduced to the interferometric phasefiltering for the first time. First, the interferometric signal is analyzed, and theinterferometric phase filtering is transformed into a local frequency estimation problem.Then, the local frequency is estimated using an amended matrix pencil at a window. Thelocal frequency can represent terrain changes, thus suggesting that the frequency can beaccurately estimated even in dense fringe regions. Finally, the local frequency is filteredby using a linear window mean filter, and the filtered phase is recovered. The proposedmethod is calculated by some matrices. Therefore, the computational complexity isreduced, and the efficiency of the interferometric phase filtering is improved.Experiments are conducted with simulated and real InSAR data. The proposed methodexhibits a better filtering effect and an ideal efficiency as compared with the traditionalfiltering method. 展开更多
关键词 INTERFEROMETRIC phase filtering INTERFEROMETRIC SYNTHETIC APERTURE radar local frequency estimation amended matrix PENCIL linear WINDOW mean filter
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ELASTIC WAVE LOCALIZATION IN TWO-DIMENSIONAL PHONONIC CRYSTALS WITH ONE-DIMENSIONAL QUASI-PERIODICITY AND RANDOM DISORDER 被引量:8
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作者 Ali Chen Yuesheng Wang +2 位作者 Guilan Yu Yafang Guo Zhengdao Wang 《Acta Mechanica Solida Sinica》 SCIE EI 2008年第6期517-528,共12页
The band structures of both in-plane and anti-plane elastic waves propagating in two-dimensional ordered and disordered (in one direction) phononic crystals are studied in this paper. The localization of wave propag... The band structures of both in-plane and anti-plane elastic waves propagating in two-dimensional ordered and disordered (in one direction) phononic crystals are studied in this paper. The localization of wave propagation due to random disorder is discussed by introducing the concept of the localization factor that is calculated by the plane-wave-based transfer-matrix method. By treating the quasi-periodicity as the deviation from the periodicity in a special way, two kinds of quasi phononic crystal that has quasi-periodicity (Fibonacci sequence) in one direction and translational symmetry in the other direction are considered and the band structures are characterized by using localization factors. The results show that the localization factor is an effective parameter in characterizing the band gaps of two-dimensional perfect, randomly disordered and quasi-periodic phononic crystals. Band structures of the phononic crystals can be tuned by different random disorder or changing quasi-periodic parameters. The quasi phononic crystals exhibit more band gaps with narrower width than the ordered and randomly disordered systems. 展开更多
关键词 phononic crystal quasi phononic crystal DISORDER localization factors plane-wavebased transfer-matrix method periodic average structure
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LOCAL INFLUENCE ANALYSIS BASED ON THE K-L DISTANCE AND THE INFORMATION DISTANCE
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作者 胡跃清 《Journal of Southeast University(English Edition)》 EI CAS 1995年第1期95-100,共6页
In this paper, the invariance of the K-L distance and that of the infor-mation distance under some parameter transformations are derived; the equiva-lence of the local influence matrix corresponding to the K-L distanc... In this paper, the invariance of the K-L distance and that of the infor-mation distance under some parameter transformations are derived; the equiva-lence of the local influence matrix corresponding to the K-L distance, the informa-tion distance and the l 展开更多
关键词 linear regression PERTURBATION measure/ local INFLUENCE matrix
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