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71.
Aiming at the deviation of pole and zero in filters which caused by the finite word length (FWL) effects,the sensitivity of pole and zero for FIR digital filters to coefficient errors was studied based on the state-space model.Unlike the IIR filter,the system matrix in state-space model of the FIR filter was defective.A set of generalized eigenvectors of defective matrix was introduced to analyze the pole sensitivity and derive the measure expression,and optimal realizations with respect to pole-zero sensitivity for FIR filters were proposed by finding optimal transformation matrices according to the similarity transformation theory.Theoretical analysis and simulation experiments show that the poles of a FIR filter are more sensitive to coefficient errors,and the proposed optimal realizations can reduce the sensitivity. 相似文献
72.
提出了二环链系统,并利用二环链特征向量,给出了一个系统可实现二环链分解的充分必要条件,给出了可实现二环链线性系统的分解算法,研究了二环链系统的稳定性和能控性. 相似文献
73.
In this paper a numerical method for calculating the hydro-dynamic coefficients for vertical plane wave motion problems in deep water is described.This procedure is developed by using the wave source method based on Green‘s theorem.The applications of the method to the cases of semi-circular and rectangular section bodies subjected to linear waves are pre-sented here,and the computed results are compared with the earlier experimental data of Vugts. 相似文献
74.
激光成像受到环境、设备自身等干扰,使得激光图像含有噪声,当前图像分割方法对噪声干扰鲁棒性差,误分割现象出现概率高,重要信息丢失严重,为了克服当前激光图像分割的弊端,提出了基于人工智能深度学习的激光图像分割方法.首先采用小波变换对激光图像进行特征提取,并对噪声干扰进行抑制处理,然后引入人工智能学习算法对激光图像特征向量进... 相似文献
75.
Indranil SenGupta 《Journal of Mathematical Analysis and Applications》2011,375(2):762-776
In this paper three-dimensional superradiance problem is considered and a differential operator that commutes with the integral operator related to the problem is obtained. All the eigenfunctions of the differential operator are found and a complete set of eigensolutions for the three-dimensional superradiance problem is obtained. 相似文献
76.
衡量互反矩阵一致性的一种新指标 总被引:1,自引:0,他引:1
本文针对AHP中利用几何平均值来估计各因素权向量的方法提出了与之匹配的一种新的衡量互反矩阵一致性的指标,并且制定了相应的衡量标准,同时将其与利用最大特征值所建立的指标入标准进行了比较与讨论。 相似文献
77.
Hui-li Wang 《Linear and Multilinear Algebra》2013,61(8):1105-1113
The eigenproblem for optimal-node matrices in max-plus algebra is shown to be solved. First, the definition of optimal-node matrix is introduced. Then for a given optimal-node matrix, it is revealed that it is easy to find all its eigenvalues and eigenvectors, which correspond to the interval time of two continuous stages and the start times of every stage of all the machines in the multi-machine interactive production process, respectively. 相似文献
78.
Alexei A. Mailybaev 《Numerical Linear Algebra with Applications》2006,13(5):419-436
The paper develops Newton's method of finding multiple eigenvalues with one Jordan block and corresponding generalized eigenvectors for matrices dependent on parameters. It computes the nearest value of a parameter vector with a matrix having a multiple eigenvalue of given multiplicity. The method also works in the whole matrix space (in the absence of parameters). The approach is based on the versal deformation theory for matrices. Numerical examples are given. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
79.
In this paper, we present heuristic techniques for the reduction of the bandwidth of a sparse matrix as well as for the reduction of the cost of the associated Cholesky factorization. Our algorithms are inspired by the spectral method of Barnard, Pothen and Simon (1995), which derives a permutation for reducing the envelope-size of a sparse matrix by computing the second eigenvector of the associated Laplacian matrix. Two main modifications of that method are proposed and tested. The first is based on the experimental observation that it is often preferable to perform only few iterations of an iterative method converging to the second eigenvector; the second is the introduction of a weighted Laplacian. These simple ideas allow us to obtain a family of spectral methods that have been carefully tested on a set of matrices whose size ranges from few hundred to one million. 相似文献
80.
CO2泵浦源是光泵气体太赫兹激光器的核心器件之一,其性能直接关系到太赫兹激光器的工作稳定性。CO2泵浦源一般由闪耀光栅作为全反射尾镜,构成特殊的光栅腔实现波长的选支输出。采用传输矩阵的特征向量法对光栅谐振腔的腔内光场模式进行了理论分析与数值模拟,计算了光栅腔的一系列本征模式及相应的衍射损耗。结果表明光栅腔的腔内模式特性等效于一个平凹腔,而对于大菲涅尔数的光栅腔, Littrow波长的附近支线也可能具有衍射损耗较低的低阶模,可能优先于Littrow波长的高阶模起振,导致光栅腔的波长选择性降低。 相似文献