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1.
In this paper, We give a mathematical model for decision With multiple goals at hierarchy process. We study problems arising from the non-program decision. Decision theory is concerned with selecting an alternative among a set of of alternatives, A choice of a optimal action is determined by choosing the action having the highest expected utility. The expected utility of each action is determined by the utility of event with its probability of occurence.  相似文献   

2.
A Steiner minimal tree (SMT) for a set of points P in the plane is a shortest networkinterconnecting P.The construction of a SMT for a general set P is known to be an NP-completeproblem.Recently,SMTs have been constructed for special sets P such as ladders,splitting trees,zigzag lines and co-circular points.In this paper we study SMTs for a wide class of point-sets calledmild bar wave.We show that a SMT for a mild bar wave must assume a special form,thus the numberof trees needed to be inspected is greatly reduced.Furthermore if a mild bar wave is also a mild rectan-gular wave,then we produce a Steiner tree constructible in linear time whose length can exceed thatof a SMT by an amount bounded by the difference in heights of the two endpoints of the rectangularwave,thus independent of the number of points.When a rectangular wave satisfies some otherconditions (including ladders as special cases),then the Steiner tree we produced is indeed a SMT.  相似文献   

3.
In this paper, a regularization Newton method for mixed complementarity problem(MCP) based on the reformulation of MCP in [1] is proposed. Its global conver-gence is proved under the assumption that F is a Po-function. The main feature of our algorithm is that a priori of the existence of an accumulation point for convergence need not to be assumed.  相似文献   

4.
GENERALIZED BOCHNER''''S THEOREM FOR RADIAL FUNCTION   总被引:3,自引:0,他引:3  
A radial function can be expressed by its generator through The positive definite of the function plays an important rote in the radial basis interpolation. We can naturally use Bochner's Theorem to check if is positive definite. This requires however a n-dhnensiotial Fourier transformation and it is not very easy to calculate. Furthermore in a lot of cases we will use for spaces of various dimensions too, then for every fixed n we need do the Fourier transformation once to check if the function is positive definite in the n-di-mensional space. The completely monotone function:, which is discussed in [4] is positive definite for arbitrary space dimensions. With this technique tve can very easily characterize the positive definite, of a radial function through its generator. Unfortunately there is only a very small subset of radial function which is completely monotone. Thus this criterion excluded a lot of interesting functions such as compactly supported radial function, whcih are very useful in applic  相似文献   

5.
The problem of solving a linear programming is converted into that of solving an uncon-strained maximization problem in which the objective function is concave. Two algorithms areproposed. These two algorithms have very simple structure and can be implemented easily. Forany given precision, the algorithms will terminate in a finite number of steps.  相似文献   

6.
In magnetoencephalography (MEG) a primary current is activated within a bounded conductive medium, i.e., the head. The primary current excites an induction current and the total (primary plus induction) current generates a magnetic field which, outside the conductor, is irrotational and solenoidal. Consequently, the exterior magnetic field can be expressed as the gradient of a harmonic function, known as the magnetic potential. We show that for the case of a triaxial ellipsoidal conductor this potential is obtained by using integration along a specific path which is dictated by the geometrical characteristics of the ellipsoidal system as well as by utilizing special properties of ellipsoidal harmonics. The vector potential representation of the magnetic field is also obtained.  相似文献   

7.
8.
In this article we define a surface finite element method (SFEM) for the numerical solution of parabolic partial differential equations on hypersurfaces F in R^n+1. The key idea is based on the approximation of F by a polyhedral surface Гh consisting of a union of simplices (triangles for n = 2, intervals for n = 1) with vertices on Г. A finite element space of functions is then defined by taking the continuous functions on Гh which are linear affine on each simplex of the polygonal surface. We use surface gradients to define weak forms of elliptic operators and naturally generate weak formulations of elliptic and parabolic equations on Г. Our finite element method is applied to weak forms of the equations. The computation of the mass and element stiffness matrices are simple and straightforward. We give an example of error bounds in the case of semi-discretization in space for a fourth order linear problem. Numerical experiments are described for several linear and nonlinear partial differential equations. In particular the power of the method is demorrstrated by employing it to solve highly nonlinear second and fourth order problems such as surface Allen-Cahn and Cahn-Hilliard equations and surface level set equations for geodesic mean curvature flow.  相似文献   

9.
§ 1 IntroductionA binary(nonbinary) sequence generated by a linear feedback shiftregister(L FSR) oflength n has the maximal period when the feedback polynomial of L FSR is prim itive.Sucha sequence is called an m- sequence of length pn- 1(p is a prime number) .m- sequences areemployed in navigation,radar and spread spectrum communication systems for theiroptimal autocorrelation properties.When a communication system uses a set of severalsignals (usually corresponding to different users) ,…  相似文献   

10.
The notion of K-Smooth space was introduced in a recent paper.Thepurpose of this paper is to give a sufficient condition for K-Smooth spaces,which will generalize a theorem of Chen Daoqi on a sufficient conditionfor the uniqueness of support functional.  相似文献   

11.
NEW RESULTS ON ESTIMATES FOR SINGULAR VALUES   总被引:2,自引:0,他引:2  
1 IntroductionTherehavebeenGerschgorin’sdisktheorem ,Brauer’stheorem ,Ostrowski’stheoremandBrualdi’stheoremetc .bywhichwecanestimatetheinclusionregionsofeigenvaluesofamatrixintermsofitsentries.(See [2 ,Chapter 6 ]) .SincethesquaresofthesingularvaluesofmatrixAa…  相似文献   

12.
在很多实际应用中需要计算大规模矩阵的若干个最小奇异组.调和投影方法是计算内部特征对的常用方法,其原理可用于求解大规模奇异值分解问题.本文证明了,当投影空间足够好时,该方法得到的近似奇异值收敛,但近似奇异向量可能收敛很慢甚至不收敛.根据第二作者近年来提出的精化投影方法的原理,本文提出一种精化的调和Lanczos双对角化方法,证明了它的收敛性.然后将该方法与Sorensen提出的隐式重新启动技术相结合,开发出隐式重新启动的调和Lanczos双对角化算法(IRHLB)和隐式重新启动的精化调和Lanczos双对角化算法(IRRHLB).位移的合理选取是算法成功的关键之一,本文对精化算法提出了一种新的位移策略,称之为"精化调和位移".理论分析表明,精化调和位移比IRHLB中所用的调和位移要好,且可以廉价可靠地计算出来.数值实验表明,IRRHLB比IRHLB要显著优越,而且比目前常用的隐式重新启动的Lanczos双对角化方法(IRLB)和精化算法IRRLB更有效.  相似文献   

13.
带小波函数的Cauchy主值积分的数值计算   总被引:4,自引:1,他引:3  
1 引言 众所周知,小波方法在信号处理和图像处理方面发挥了举世瞩目的成就。近年来人们研究小波方法在数值分析方面的应用。期望在数值求解微分方程和积分方程方面发挥良好的作用。本文研究带有小波函数的Cauchy主值积分 的数值计算方法,其中Φ(x)是紧支撑的尺度函数。这是数值求解积分方程的核心问题之一。 1.l 多分辩分析 空间L~2(R)中的一个多分辩分析是这样的闭子空间列{V_j},它满足下列条件 1) 2) 3) 4)存在尺度函数,使构成V_o的Riesz基,从而也存在序列使满足双尺度方程  相似文献   

14.
本文研究一类多项式系统的高次奇点和无穷远点的中心问题,对有限奇点(原点)和无穷远点(Poincare球面上的赤道)的中心问题进行统一处理,给出了系统原点和无穷远点为中心的一个充分条件。  相似文献   

15.
潘佳庆 《数学杂志》2003,23(4):452-454
本文讨论非线性椭圆型方程的Dirichlet问题.利用Schauder不动点定理及先验估计方法得到主要结果:存在正的光滑解.  相似文献   

16.
一类高阶椭圆型方程奇摄动边值问题   总被引:1,自引:1,他引:0  
莫嘉琪  张伟江 《数学杂志》1997,17(3):315-320
本文讨论了一类2m阶奇摄动椭圆型方程边值问题的渐近性态,得到了问题解的一致有效的渐近展开式。  相似文献   

17.
By two successive linear transformations,a singularly perturbed differential system with two parameters is quasi-diagonalized. The method of variation of constants and the principle of contraction map are used to prove the existence of the transformations.  相似文献   

18.
研究了一类奇异跳跃系统的鲁棒稳定和镇定问题.在所研究的系统中,假设系数和转移率的不确定项范数有界.通过构造Lyapunov-Krasovskii函数,得到的充分条件可以保证系统在一定程度不确定性的影响下,是正则,无脉冲和均值意义下随机稳定的.最后,算例说明了所给方法的有效性.  相似文献   

19.
石兰芳 《数学杂志》2004,24(1):19-23
本文讨论了一类奇摄动高阶椭圆型方程Dirichlet问题,利用伸长变量和变界层校正法,得到了问题解的形式渐近展开式.再用微分不等式理论,证明了解的一致有效性.  相似文献   

20.
冯依虎  莫嘉琪 《数学杂志》2016,36(2):239-245
本文研究了一类奇摄动非线性分数阶微分方程初值问题.利用伸长变量构造出解的形式展开式,并利用微分不等式理论,证明了解的一致有效的渐近式.所得的结果具有较好精度的近似解.  相似文献   

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