共查询到20条相似文献,搜索用时 100 毫秒
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黄永念曾对一个二阶张量引进了一个特征张量的概念,且利用它给出了一个常系数常微分方程组得显式解表达式.最近发现这种特征张量是并矢形式.利用这种并矢表示可以大大简化张量的运算工作. 相似文献
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赵秀恒 《数学的实践与认识》2002,32(1):94-96
文中给出了一致凸空间中 Chebyshev中心的一个特征 ,推广了 D.Amir和 J.Mach关于 Hilbert空间中的一个结果 . 相似文献
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连续型概率度量的特征及其应用 总被引:1,自引:1,他引:0
讨论了连续型概率度量空间,给出了连续型概率度量的特征定理.利用这个特征定理,我们获得了连续型概率度量空间的闭球套定理和M enger空间完备性特征定理.作为本文的应用获得了一个局部概率压缩映象不动点定理. 相似文献
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π-可分群中关于正规π-子群的π-Brauer特征标 总被引:1,自引:0,他引:1
本文研究了有限π可分群中关于正规π子群的πBrauer特征标,利用Isaacs的经典Bπ特征标理论和特征三元组理论,得到了有限π可分群上的一个类函数空间的一个经典基. 相似文献
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对高维数据进行判别分析,典型的策略包含数据压缩、特征提取与特征选择三步.该文对于选择合适的特征进行判别分析提出了一个定理,并应用这个定理对常用的主成分判别方法作了改进.最后,作者把改进的方法与两种常用的方法应用于一个神经生理试验数据的判别分析.结果表明,在保证判别能力的同时,改进后的方法下用于判别的特征减少了 相似文献
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蒋威 《数学物理学报(A辑)》2007,27(6):1006-1012
该文首先研究了退化时滞微分系统的特征根分布, 指出如果退化时滞微分系统的所有特征根都具有负实部, 在一个条件下, 特征根的负实部的最大值为负.由此可以得到一个条件, 在该条件下如果所有特征根都具有负实部, 则退化时滞微分系统的解是指数稳定的.作为例子, 对中立型给出其解为指数稳定的条件. 相似文献
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Zhang Zhihua 《分析论及其应用》2002,18(3):42-51
In Sobolev space H-12π of periodic distributions, a multiresolution analysis is established, and then it isshown that a corresponding orthonormal basis generated by a single mother function except the first element. 相似文献
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ZhangZhihua 《逼近论及其应用》2002,18(3):42-51
In Sobolev space H2π^-1 of periodic distributions,a multiresolution analysis is established,and then it is shown that a corresponding orthonormal basis generated by a single mother function except the first element. 相似文献
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We characterize uniform convergence rates in Sobolev and local Sobolev spaces for multiresolution analyses. 相似文献
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多分辨分析的概念在小波基构造中起着非常重要的作用,并经历了从经典多分辨分析到多重多分辨分析,再到矩阵值多分辨分析的研究历程.本文基于矩阵值多分辨分析,研究并给出了矩阵值函数空间中尺度空间稠密性的两个充要条件,并在此基础之上得到了稠密性的两个充分条件. 相似文献
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Characterization of Smoothness of Multivariate Refinable Functions in Sobolev Spaces 总被引:8,自引:0,他引:8
Rong-Qing Jia 《Transactions of the American Mathematical Society》1999,351(10):4089-4112
Wavelets are generated from refinable functions by using multiresolution analysis. In this paper we investigate the smoothness properties of multivariate refinable functions in Sobolev spaces. We characterize the optimal smoothness of a multivariate refinable function in terms of the spectral radius of the corresponding transition operator restricted to a suitable finite dimensional invariant subspace. Several examples are provided to illustrate the general theory.
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We develop a stability and convergence analysis of Galerkin–Petrov schemes based on a general setting of multiresolution generated
by several refinable functions for the numerical solution of pseudodifferential equations on smooth closed curves. Particular
realizations of such a multiresolution analysis are trial spaces generated by biorthogonal wavelets or by splines with multiple
knots. The main result presents necessary and sufficient conditions for the stability of the numerical method in terms of
the principal symbol of the pseudodifferential operator and the Fourier transforms of the generating multiscaling functions
as well as of the test functionals. Moreover, optimal convergence rates for the approximate solutions in a range of Sobolev
spaces are established.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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Rong-Qing Jia 《Advances in Computational Mathematics》2009,30(2):177-200
In this paper we investigate spline wavelets on the interval with homogeneous boundary conditions. Starting with a pair of
families of B-splines on the unit interval, we give a general method to explicitly construct wavelets satisfying the desired
homogeneous boundary conditions. On the basis of a new development of multiresolution analysis, we show that these wavelets
form Riesz bases of certain Sobolev spaces. The wavelet bases investigated in this paper are suitable for numerical solutions
of ordinary and partial differential equations.
Supported in part by NSERC Canada under Grant OGP 121336. 相似文献
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A. G. García J. M. Kim G. Pérez-Villalón 《Numerical Functional Analysis & Optimization》2013,34(1-2):126-144
Alising error arises whenever a sampling formula, valid for a prescribed space, is applied to a function in a bigger space. In this work, we estimate the aliasing error of classic and average sampling expansions in wavelet subspaces of a multiresolution analysis. 相似文献