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1.
广义正定矩阵的进一步研究   总被引:2,自引:1,他引:1  
基于正定矩阵的几个定义,首先给出了广义正定矩阵的一些新性质,其次研究了广义正定矩阵与H-矩阵、M-矩阵的关系,推广和改进了文献中的有关行列式不等式.  相似文献   

2.
主要研究了两个M-矩阵的比较性质与不等式,给出了M-矩阵与逆M-矩阵Hadamard-Fisher不等式等式成立的矩阵结构.  相似文献   

3.
本文研究了一类特殊的逆M-矩阵.利用有向图中的性质和方法,获得了逆M-矩阵其逆为三对角矩阵的充分必要条件,推广了常见的D-型矩阵,得到了一类矩阵为逆M-矩阵的条件.  相似文献   

4.
非奇H-矩阵在科学和工程实际中有着广泛地应用,但在实际中判定一个矩阵是否为非奇H-矩阵是比较困难的.通过构造不同的正对角阵,结合不等式的放缩技巧,给出了一些比较实用的新条件,改进和推广了现有的一些结论,并给出相应的一些数值算例来说明结果的有效性.  相似文献   

5.
H-矩阵在许多领域中都起着非常重要的作用,例如数学分析、矩阵理论、数学经济学、控制论等.但是在实际运用中判定H-矩阵却十分困难.本文类似于文[4],均以α-对角占优理论为基础,给出H-矩阵的若干实用判定,改进了文[3]的相应结果.  相似文献   

6.
给出了完全主正矩阵的凸性不等式和Minkowski型不等式,并推出了M矩阵,亚正定矩阵等类型的矩阵在一定条件下的凸性不等式和Minkowski型不等式.  相似文献   

7.
<正>1引言众所周知,包括数学、物理、力学和工程数学在内的许多实际问题常常归结为对一些大型线性代数方程组的求解,而这些大型线性代数方程组的系数矩阵往往是H-矩阵(见文[9]).因此如何判断一个矩阵是H-矩阵一直是人们关心的重要课题.本文根据γ-对角占优矩阵的相关性质,并利用不等式的放缩技巧和划分矩阵指标集的方法,给出了几个判别H-矩阵的充分条件.最后,结合数值实例来说明本文所给判据的有效性和优越性.  相似文献   

8.
A=[aij]∈Mn和B=[b(ij(]∈Mn的Hadamard积可表示为AoB=[aijbij]∈Mn.如果A,B∈Mn是M-矩阵,那么AoB-1也是M-矩阵.证明了(a)一个非奇异的M-matrix是一对M-矩阵和逆M-矩阵的Hadamard积,同时也证明了(b)一个P-矩阵是两个P-矩阵的Hadamard积.  相似文献   

9.
矩阵平方根在数学的许多应用中起着重要的作用.本文研究M-矩阵平方根的计算问题,提出一种计算正则M-矩阵平方根的迭代方法.首先将这个问题转化为M-矩阵代数Riccati方程,进而提出一种有效的方法来求解这个特殊的MARE.理论分析表明,该方法在一定条件下是收敛的.数值实验表明该方法是可行的,且优于二项式迭代法.  相似文献   

10.
非奇异矩阵的逆是矩阵元素的连续函数.学者们也对矩阵广义逆的连续性有所研究.本文应用矩阵分裂和两个矩阵之和的逆的展开式,给出了一般非奇异矩阵,M-矩阵和H-矩阵的逆的连续性.当一些合理的条件满足时,这几种矩阵的逆是连续的.  相似文献   

11.
A kinetic equation (S-model) is used to solve the nonstationary problem of a monatomic rarefied gas flowing from a tank of infinite capacity into a vacuum through a long plane channel. Initially, the gas is at rest and is separated from the vacuum by a barrier. The temperature of the channel walls is kept constant. The flow is found to evolve to a steady state. The time required for reaching a steady state is examined depending on the channel length and the degree of gas rarefaction. The kinetic equation is solved numerically by applying a conservative explicit finite-difference scheme that is firstorder accurate in time and second-order accurate in space. An approximate law is proposed for the asymptotic behavior of the solution at long times when the evolution to a steady state becomes a diffusion process.  相似文献   

12.
We obtain an exact estimate for the minimum multiplicity of a continuous finite-to-one mapping of a projective space into a sphere for all dimensions. For finite-to-one mappings of a projective space into a Euclidean space, we obtain an exact estimate for this multiplicity for n = 2, 3. For n ≥ 4, we prove that this estimate does not exceed 4. Several open questions are formulated.  相似文献   

13.
We study the asymptotic behavior at large time of a solution to a system of nonlinear integro-differential equations which arises in mathematical modeling of diffusion of a magnetic field into a substance. We establish the corresponding stabilization rate.  相似文献   

14.
We consider a nonlocal reaction-diffusion equation as a model for a population structured by a space variable and a phenotypic trait. To sustain the possibility of invasion in the case where an underlying principal eigenvalue is negative, we investigate the existence of travelling wave solutions. We identify a minimal speed c* > 0, and prove the existence of waves when c ≥ c* and the nonexistence when 0 ≤ c < c*.  相似文献   

15.
Benth and Karlsen [F.E. Benth, K.H. Karlsen, A note on Merton's portfolio selection problem for the Schwartz mean-reversion model, Stoch. Anal. Appl. 23 (2005) 687-704] treated a problem of the optimisation of the selection of a portfolio based upon the Schwartz mean-reversion model. The resulting Hamilton-Jacobi-Bellman equation in 1+2 dimensions is quite nonlinear. The solution obtained by Benth and Karlsen was very ingenious. We provide a solution of the problem based on the application of the Lie theory of continuous groups to the partial differential equation and its associated boundary and terminal conditions.  相似文献   

16.
The problem of the motion of a container in a curved section of a horizontal pipeline is solved using second-order Lagrange equations in the presence of nonholonous couplings. The special case of the motion of a container in a circular curve is examined.Translated from Matematicheskie Metody i Fiziko-Mekhanicheskie Polya, No. 25, pp. 90–95, 1987.  相似文献   

17.
In many real life applications a group of people interact through a communication network, mathematically modelled as a connected graph linking each element of the group. These participants may have diverse objectives and play very different roles depending on their knowledge and privileges. We focus on a particular scenario, in which a certain node is absolutely essential for completing the intended task. Moreover, if a technical failure results in disconnection of a participant to this leader node, this participant can no longer take part in the group's performance.  相似文献   

18.
Let G be a graph with vertex set V, and let h be a function mapping a subset U of V into the real numbers R. If ? is a function from V to R, we define δ (?) to be the sum of ∥?(b)? ?(a)∥ over all edges {a, b} of G. A best extension of h is such a function ? with ?(x) = h(x) for XU and minimum δ (?). We show that such a best extension exists and derive an algorithm for obtaining such an extension. We also show that if instead we minimise the sum of (?(b)??(a))2, there is generally a unique best extension, obtainable by solving a system of linear equations.  相似文献   

19.
Consider the following game of a cop locating a robber on a connected graph. At each turn, the cop chooses a vertex of the graph to probe and receives the distance from the probe to the robber. If she can uniquely locate the robber after this probe, then she wins. Otherwise the robber may either stay put or move to any vertex adjacent to his location other than the probe vertex. The cop’s goal is to minimize the number of probes required to locate the robber, while the robber’s goal is to avoid being located. This is a synthesis of the cop and robber game with the metric dimension problem. We analyse this game for several classes of graphs, including cycles and trees.  相似文献   

20.
《Discrete Mathematics》2007,307(7-8):892-895
Results on the existence of a cycle containing a given linear forest are proved.  相似文献   

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