Fast blind estimation algorithm for Hamming codes parameters

An algorithm is proposed for fast blindly estimating the length, the starting point and the parity-check matrix of the hamming code. First, an intercepted matrix is built by the data received, and by exploiting an assumed number of parity-check digits and the assumed starting point of the hamming code. Then, a parity-check matrix is obtained by the assumed primitive polynomial, and when all its row-vectors are dual codes of the intercepted matrix, the hamming code parameters could be estimated. Moreover, a theoretical analysis of the proposed algorithm is made. Simulation results verify the good performance of the proposed method.     

基于埃尔米特插值的秘密分割门限方案的构造

该文在Shamir门限方案的基础上，利用埃尔米特插值构造了一个秘密分割门限方案，证明了方案构造的可行性，并对它的安全性进行了讨论。     

关于Hermite矩阵的迹的一个不等式

给出了一个关于Hermite矩阵的迹的不等式，并用其推导出了平均值不等式．     

非线性判别函数的基于MDL标准的勒让德多项式构造法

1.引言在模式识别中,分类决策问题是最基础也是最重要的内容,所谓分类决策就是根据被识别对象特征的观察值将其分到某个类别中去,其基本作法是在样本训练集基础上确定某个判决规则(即样本特征空间的一个函数,也称为判别函数或分类器),使按这种判决规则对被识别对象进行分类所造成的错误率最小或引起的损失最小。当样本分布是正态分布时,从最小错误率来说二次分类器是最优分类器。此外,作为一种特殊情况,如果这些分布有相同的协方差矩阵,那么线性分类器就是最优的。然而这些假定在很多实际问题中并不成立,因此线性或二次分类器对     

Computation of Determinants, Adjoint Matrices, and Characteristic Polynomials without Division

Algorithms are proposed for computing the characteristic polynomial, determinant, and adjoint matrix for a n × n matrix and for solving a system of n-1 linear homogeneous equations in n variables by Cramer's rule using O(n ⁴ ) ring operations (without the division operation) over an arbitrary commutative ring. The exponent in the estimate of the computation time can be additionally reduced if an algorithm of asymptotically fast matrix multiplication is used.     

Sufficient algebraic conditions for stability of cones of polynomials

In this paper a sufficient condition for a cone of polynomials to be Hurwitz is established. Such condition is a matrix inequality, which gives a simple algebraic test for the stability of rays of polynomials. As an application to stable open-loop systems, a cone of gains c such that the function u=−kc^Tx is a stabilizing control feedback for all k>0 is shown to exist.     

子样广义方差的分布函数及其计算

本文以傅氏级数为基础，巧妙地利用了契贝谢夫多项式，成功地给出了子样广义方差的分布函数及其计算过程。     

关于埃尔米特插值的最小二乘问题

本文讨论埃尔米特插值的最小二乘问题,导出了此问题的正规方程组,证明了埃尔米特插值的最小二乘解的存在唯一性。     

A method for tracking internal crack propagation in railhead

This paper presents a method for tracking two-dimensional propagation of internal cracks, in particular vertical split head (VSH) defects, due to contact loading in railhead. Generalised curved crack is assumed to have present in the railhead and its propagation is simulated by solving interaction of arbitrary shaped cracks successively. Furthermore, the finite shape of the rail section is also modelled as the continuous distribution of dislocation within an infinite plane. Crack propagation is simulated using the criterion of vanishing of Mode II stress intensity factors (SIF) at crack tips. Examples are provided for tracking the propagation of pre-existing internal cracks in railheads turning into VSH defects under centric contact loading.     

On discrete multivariate distributions symmetric in frequencies

In this paper we describe a new class of discrete multivariate distributions which verify that their probability mass function is invariant when their univariate variables are permuted. These distributions may be generated by a multivariate extension of the Gauss function₂ F ₁ with matrix argument. A methodology that permits the fit of these distributions to real data is developed. A fit of a distribution for bivariate real data is shown and is compared with fits obtained by means of other usual bivariate distributions generated by extensions of the Gauss function.