多项式的重根判别式和代数基本定理的简证

运用齐次线性方程组的理论研究实数域上多项式根的问题,给出了n次实系数多项式在复数域上存在某种特殊非零重根的判别公式,同时给出了代数基本定理的一个简洁的代数证明.     

保护私有信息的一般线性方程组计算协议

作为科学计算的一个重要问题,保护私有信息的线性方程组的求解在金融、机械及通信等领域有着广泛的应用.在不经意传输的意义下,利用有限域上计算Moore-Penrose伪逆矩阵的概率算法,设计新的安全协议,解决了隐私保护的一般线性方程组在有限域上的安全两方计算问题,并利用模拟范例证明该协议在半诚实模型下是安全的.     

模态谓词演算的判定问题(Ⅱ)——关于Slomson归约

以M表示[2]中讨论过的模态谓词演算S_ε~*(它等价于[5]中的S5~*)的仅含唯一的一目谓词字母K的子系统,以B_o~N表域为N的B_o值全函项一目Boole代数,此处N为全体自然数所成之集,B_o为二元Boole代数、本文证明了如下结果: M中的定理(即在S_ε~*中可证明的语句)所成之集和在一非空有穷集上对B_o~N可驳的语句所成之集是递归不可分的. 后一结果加强了和Slomson分别在[8]和[12]中相互独立地得到的一个结果,即M的判定问题是不可解的;同时否定地解决了M中的语句之是否在一非空有穷域上对B_o~N可驳的判定问题.     

四元数积的弱可交换性及其一个应用

用向量表示四元数.得到四元数乘积的一个弱可交换律,并利用它将四元数体上线性矩阵方程转化为数域上的线性方程组,给出此类方程的一般解法.     

α-型及其应用

本文以α型为基本工具研究代数问题，给出了Abian结果的一个进一步的结果，并给出了域上的无限线性方程组有解的一点判定准则。     

关于线性子空间与仿射子空间的注记

作为线性方程组的逆问题,本文刻划了线性子空间与仿射子空间分别是某一齐次与非齐次线性方程组的解集,并给出了利用矩阵初等行变换求解相应线性方程组的简便方法;进一步通过仿射子空间引入商空间的概念,建立线性空间的同态基本定理,从而得到维数公式的一个新的证明.     

双重指数函数的幂级数可展性

考察一个函数在给定区间上是否可展为麦克劳林级数,一般是判断余项在该区间上是否趋于0．利用该方法,通过建立一个级数估计式。给出双重指数函数Y=e,在实数域上的可展性证明．     

关于线性方程组的进一步讨论

现行的各种《高等代数》教科书对数域F上线性方程组:的解进行了详细的讨论,并给出导出齐次方程组的解的结构定理: 定理1:数域F上的一个n个未知量的齐次线性方程组(2)的一个解作成F~n的一个子空间,称为这个齐次线性方程组的解空间,如果所     

F_2上一类多项式不可约因子个数的奇偶性

利用Stickel berger-Swan定理,本文给出了二元域F2上一类特殊形式多项式xl-ef(xf+1)e+1的不可约因子个数的奇偶性,由该结论可得到二元域上非平方三项式的不可约因子个数奇偶性的推论,此推论与Swan给出的关于三项式的定理一致,同时本文还给出了一类五项式在二元域中不可约因子个数奇偶性的类似结论.     

善用初等变换展开线性代数理论教学

初等变换是线性代数的基本变换,在线性代数课程中常常被用来计算,例如求解线性方程组、计算方阵的行列式、矩阵的求逆以及更一般的矩阵方程AX=B的求解、计算整数矩阵和域上多项式矩阵的Smith标准形、以及计算对称阵的相合标准形等.本文说明如何灵活利用初等变换,给出线性代数课程中一些重要理论结果的系统而又简洁的证明.     

Analytical and numerical method of finite bodies for calculation of cylindrical orthotropic shell with rectangular hole

To solve the boundary-value problem for cylindrical orthotropic shell with sizeable rectangular hole we suggest analytical and numerical method of finite bodies. For determination of the stress state of orthotropic thin-walled cylinder we use a systemof equations that exactly satisfies the equilibrium equations of orthotropic cylindrical shell. Representation of the solutions is divided into basic and self-equilibrium state. For some loads of a shell we build the basic stress state. We obtain a countable number of resolving functions that exactly satisfy the equations of a shell and describe the self-equilibrium stress state. We develop the algorithm of the analytical and numerical solutions of boundary-value problem based on approximation of the stress state of a shell by finite sum of resolving functions and propose a universal way of reduction of all conditions of the contact parts of the enclosure and the boundary conditions to minimize the generalized quadratic forms. We establish criteria under which the construction of approximate solutions coincides with the exact one.     

Column Generation Algorithms for Nonlinear Optimization,I: Convergence Analysis

Column generation is an increasingly popular basic tool for the solution of large-scale mathematical programming problems. As problems being solved grow bigger, column generation may however become less efficient in its present form, where columns typically are not optimizing, and finding an optimal solution instead entails finding an optimal convex combination of a huge number of them. We present a class of column generation algorithms in which the columns defining the restricted master problem may be chosen to be optimizing in the limit, thereby reducing the total number of columns needed. This first article is devoted to the convergence properties of the algorithm class, and includes global (asymptotic) convergence results for differentiable minimization, finite convergence results with respect to the optimal face and the optimal solution, and extensions of these results to variational inequality problems. An illustration of its possibilities is made on a nonlinear network flow model, contrasting its convergence characteristics to that of the restricted simplicial decomposition (RSD) algorithm.     

The tightness in the ergodic analysis of regenerative queueing processes

The tightness of some queueing stochastic processes is proved and its role in an ergodic analysis is considered. It is proved that the residual service time process in an open Jackson-type network is tight. The same problem is solved for a closed network, where the basic discrete time process is embedded at the service completion epochs. An extention of Kiefer and Wolfowitz's “key” lemma to a nonhomogeneous multiserver queue with an arbitrary initial state is obtained. These results are applied to get the ergodic theorems for the basic regenerative network processes. This revised version was published online in June 2006 with corrections to the Cover Date.     

The road coloring problem

A synchronizing word of a deterministic automaton is a word in the alphabet of colors (considered as letters) of its edges that maps the automaton to a single state. A coloring of edges of a directed graph is synchronizing if the coloring turns the graph into a deterministic finite automaton possessing a synchronizing word. The road coloring problem is the problem of synchronizing coloring of a directed finite strongly connected graph with constant outdegree of all its vertices if the greatest common divisor of lengths of all its cycles is one. The problem was posed by Adler, Goodwyn and Weiss over 30 years ago and evoked noticeable interest among the specialists in the theory of graphs, deterministic automata and symbolic dynamics. The positive solution of the road coloring problem is presented.     

Jamming communication networks under complete uncertainty

This paper describes a problem of interdicting/jamming wireless communication networks in uncertain environments. Jamming communication networks is an important problem with many applications, but has received relatively little attention in the literature. Most of the work on network interdiction is focused on preventing jamming and analyzing network vulnerabilities. Here, we consider the case where there is no information about the network to be jammed. Thus, the problem is reduced to jamming all points in the area of interest. The optimal solution will determine the locations of the minimum number of jamming devices required to suppress the network. We consider a subproblem which places jamming devices on the nodes of a uniform grid over the area of interest. The objective here is to determine the maximum grid step size. We derive upper and lower bounds for this problem and provide a convergence result. Further, we prove that due to the cumulative effect of the jamming devices, the proposed method produces better solutions than the classical technique of covering the region with uniform circles.     

Using matrices to link conflict evolution and resolution in a graph model

The graph model for conflict resolution provides a convenient and effective means to model and analyze a strategic conflict. Standard practice is to carry out a stability analysis of a graph model, and then to follow up with a post-stability analysis, an important component of which is status quo analysis. A graph model can be viewed as an edge-colored graph, but the fundamental problem of status quo analysis – to find a shortest colored path from the status quo node to a desired equilibrium – is different from the well-known network analysis problem of finding the shortest path between two nodes. The only matrix method that has been proposed cannot track all aspects of the evolution of a conflict from the status quo state. Our explicit algebraic approach is convenient for computer implementation and, as demonstrated with a real world case study, easy to use. It provides new insights into a graph model, not only identifying all equilibria reachable from the status quo, but also how to reach them. Moreover, this approach bridges the gap between stability analysis and status quo analysis in the graph model for conflict resolution.     

Hedging electricity swaptions using partial integro-differential equations

The basic contracts traded on energy exchanges are swaps involving the delivery of electricity for fixed-rate payments over a certain period of time. The main objective of this article is to solve the quadratic hedging problem for European options on these swaps, known as electricity swaptions. We consider a general class of Hilbert space valued exponential jump-diffusion models. Since the forward curve is an infinite-dimensional object, but only a finite set of traded contracts are available for hedging, the market is inherently incomplete. We derive the optimization problem for the quadratic hedging problem under the risk neutral measure and state a representation of its solution, which is the starting point for numerical algorithms.     

Superstabilization of linear dynamic plants under operator disturbances

We consider the state stabilization problem for a linear stationary plant whose parameters and dynamic order can change jumpwise in the course of operation, which leads to changes in its mathematical model. We assume that the set of all possible mathematical models corresponding to the plant is finite. To solve this problem, we suggest to use the simultaneous superstabilization method and the dynamic order extension method.     

Characterization of local solutions for a class of nonconvex programs

A nonconvex programming problem, which arises in the context of application of Benders' decomposition procedure to a class of network optimization problems, is considered. Conditions which are both necessary and sufficient for a local maximum are derived. The concept of a basic local maximum is introduced, and it is shown that there is a finite number of basic local maxima and at least one such local maximum is optimal.     

Threshold of Effective Degree SIR Model

The effective degree SIR model is a precise model for the SIR disease dynamics on a network. The original ODE model is only applicable for a network with finite degree distributions. The new generating function approach rewrites with model as a PDE and allows infinite degree distributions. In this paper, we first prove the existence of a global solution. Then we analyze the linear and nonlinear stability of the disease-free steady state of the PDE effective degree model, and show that the basic reproduction number still determines both the linear and the nonlinear stability. Our method also provides a new tool to study the effective degree SIS model, whose basic reproduction number has been elusive so far.