线性映射的值域与核的结构定理及其应用

本文利用同构关系与解析方法研究了值域与核的基和维数,弄清了值域与核的几何结构,通常的维数公式是其推论,然后列举若干例子阐明其应用.     

线性变换的核或象一致的刻划

线性变换的核或象一致的刻划李兴蕙（黑龙江省教育学院数学系１５００８０）高等代数教材［１］与［２］，对干两个线性变换核相等或象相等的情形没有阐述，致使某些概念（如矩阵的行、列等价，方程组的同解等）的发展，不能展现全貌，因此，有必要探讨核或象一致的线性变...     

线性空间维数同数域的关系

一组向量是否线性相关,同数域是否有关?回答是肯定的。例如,向量组 α_1=(1,0),α_2=(2~(1/2),0)在实数城R上线性相关,而在有理数域Q上线     

关于线性变换特征分解定理的证明

高等代数教材关于线性特征分解定理的证明过程迂回曲折,不便于理解和掌握.通过揭示线性变换值域与核的关系,调整证明思路,可简化证明步骤.     

谈高等代数的解析法与几何法

在同构理论的框架下,线性空间V的任一向量对应于P~n的一个n维向量,V的任一线性变换对应于P~(n×n)的一个n阶矩阵.因此,用矩阵的方法,即解析法,处理线性空间和线性变换的问题,或用几何法处理矩阵问题变成了现实.作为教材内容的补充,本文试图通过若干例子探讨如何综合运用解析法与几何法解决高等代数问题.     

有限维弱空间的维数定理

向量空间的维数公式，可以推广到比子空间更广的一类弱空间。     

k个矩阵的核子空间的和的维数

利用齐次线性方程组的解的表达式及分块矩阵的一个秩等式,得出了k个矩阵的核子空间的和的维数的一个公式,它推广了维数公式.并给出了这个公式的几个应用.     

关于线性变换的像空间与核空间的直和

讨论数域P上有限维线性空间V上线性变换A的方幂A~k的像空间ImA~k与核空间KerA~k的直和,并将结论推广到无限维线性空间.证明了:V=ImA~k+KerA~k当且仅当ImA~k=ImA~(k+1),以及ImA~k∩KerA~k=0当且仅当KerA~k=KerA~(k+1).     

内积关系与线性变换的探讨

当欧氏空间Ｖ的变换满足一定的内积关系时，它便是Ｖ的线性变换．本文较全面、深入地讨论了这一问题，并对文［１］进行了剖析．定理１设Ｔ为欧氏空间Ｖ的一个变换，ｆ（ｘ）∈Ｒ［ｘ］，（以ｘ为未定元的实多项式环）．如果α，β∈Ｖ，都有〈Ｔ（α），β〉＝〈α，ｆ...     

无穷维Hamilton算子的二次数值域

研究了一类无界无穷维Hamilton算子的二次数值域的性质,进而,应用二次数值域来刻画了无穷维Hamilton算子谱的分布范围,并给出了二次数值域的闭包包含谱集的结论.     

Novel Linear Image Denoising Approach Based on a Modified Gaussian Filter Kernel

A Gaussian noise reduction technique for grayscale images is proposed in this article. It uses a modified Gaussian filter kernel based on a hyperbolic second-order equation. The introduced mathematical model differs from the classic Gaussian model provided by the heat equations, by a localization property. Our filtering approach reduces the amount of Gaussian noise and also enhances the image contrast. Some image denoising experiments that prove the effectiveness of the proposed method are also described in this article.     

核空间与像空间构成直和的条件

根据线性变换与矩阵之间的联系,利用Jordan标准型给出线性变换的核空间与像空间构成直和的条件,即线性变换的特征值不含零,或以零为特征值的Jordan块均为一阶.     

On the Reproducing Kernel Hilbert Spaces Associated with the Fractional and Bi-Fractional Brownian Motions

We present decompositions of various positive kernels as integrals or sums of positive kernels. Within this framework we study the reproducing kernel Hilbert spaces associated with the fractional and bi-fractional Brownian motions. As a tool, we define a new function of two complex variables, which is a natural generalization of the classical Gamma function for the setting we consider. D. Alpay thanks the Earl Katz family for endowing the chair which supports his research.     

一类线性回归模型中核估计的渐近性质

考虑固定设计下具有一阶非参数自回归误差的线性模型,构造了参数和非参数函数的N-W核估计,在适当的条件下,证明了参数估计的强相合性,同时给出了非参数函数估计的渐近正态性.     

基于线性规划核心矩阵的单纯形算法

本文讨论了线性规划中的核心矩阵及其特性,探讨了利用核心矩阵实现单纯形算法的可能性,并进一步提出了一个基于核心矩阵的两阶段原始一对偶单纯形方法,该方法通过原始和对偶两个阶段的迭代,可以在有限次迭代中收敛到原问题的最优解或证明问题无解或无界．在试验的22个问题中,该算法的计算效率总体优于基于传统单纯形方法的MINOS软件．     

部分线性自回归模型中误差方差的核估计

基于非参数函数的核估计,构造了部分线性自回归模型中误差四阶矩的相合估计,从而给出了误差方差核估计的渐近正态性,并通过模拟算例和实例说明了其应用.     

Dimensions of the type dim and Alexandroff spaces

Alexandroff spaces have all the properties of finite spaces and therefore play an important role in digital topology, image analysis, and computer graphics. In this paper we study dimensions of the type dim for the class of all Alexandroff countable topological spaces using matrix algebra.     

On Measuring the Efficiency of Kernel Operators in L p (R d )

It is well known that it is possible to enhance the approximation properties of a kernel operator by increasing its support size. There is an obvious tradeoff between higher approximation order of a kernel and the complexity of algorithms that employ it. A question is then asked: how do we compare the efficiency of kernels with comparable support size? We follow Blu and Unser and choose as a measure of the efficiency of the kernels the first leading constant in a certain error expansion. We use time domain methods to treat the case of globally supported kernels in L _p (R ^d), 1≤p≤∞.

     

Linear Transformation of Products: Games and Economies

In this paper, we introduce situations involving the linear transformation of products (LTP). LTP situations are production situations where each producer has a single linear transformation technique. First, we approach LTP situations from a (cooperative) game theoretical point of view. We show that the corresponding LTP games are totally balanced. By extending an LTP situation to one where a producer may have more than one linear transformation technique, we derive a new characterization of (nonnegative) totally balanced games: each totally balanced game with nonnegative values is a game corresponding to such an extended LTP situation. The second approach to LTP situations is based on a more economic point of view. We relate (standard) LTP situations to economies in two ways and we prove that the economies are standard exchange economies (with production). Relations between the equilibria of these economies and the cores of cooperative LTP games are investigated.