Formanek中心多项式的唯一构作

Formanek constructed the first central polynomial. i .e. G₁+ G₂+… + G_n where G₁= G(x, y₁,…, y_n), G₂= G(x, y₂, y₃,…, y_n, y₁) etc. Are called Forma nek's polynomials. Rosset in his nota [3] raised the question that whether all sgmmetic polynomials in G_i also give central polynomials. He showed that the basic sgmmetric polynomials in G_i are not all central. In this paper we shall show, for n≥3 each polynomial in G_j is not central, except f(G₁+ …+ G_n, where f(x)is a polynomial at x. Hence Formanek's central polynomial is unique in some sense.     

非定常边界层问题整体解的存在唯一性

研究粘性不可压缩流体中的边界层问题. 通过引进变换, 将原来边界层问题化为仅含有一个方程的拟线性抛物方程的初边值问题. 对于不同情形, 分别证明了该问题整体解与局部解的存在唯一性.     

截断型亚纯映射的唯一性定理涉及到小映射的情形

唯一性定理是多复变值分布中重要的定理之一,本文在已有的研究成果上,运用Thai最新得到的第二基本定理,给出了多复变中截断型亚纯映射新的唯一性定理涉及到小映射情形.     

Global Existence for a Parabolic-hyperbolic Free Boundary Problem Modelling Tumor Growth

In this paper we study a free boundary problem modelling tumor growth, proposed by A. Friedman in 2004. This free boundary problem involves a nonlinear second-order parabolic equation describing the diffusion of nutrient in the tumor, and three nonlinear first-order hyperbolic equations describing the evolution of proliferative cells, quiescent cells and dead cells, respectively. By applying Lp theory of parabolic equations, the characteristic theory of hyperbolic equations, and the Banach fixed point theorem, we prove that this problem has a unique global classical solution.     

正四面体套中心构型的存在唯一性

Two cases of the nested configurations in R^3 consisting of two regular quadrilaterals are discussed. One case of them do not form central configuration, the other case can be central configuration. In the second case the existence and uniqueness of the central configuration are studied. If the configuration is a central configuration, then all masses of outside layer are equivalent, similar to the masses of inside layer. At the same time the following relation between r(the ratio of the sizes) and mass ratio b = m/m must be satisfied b=24(3的立方根)（3r^2 2r 3）^-3/2-8（1-r）|1-r|^-3-3(6r的立方根)/24(3的立方根)（3 r）（3r^2 2r 3）^-3/2-8r（1-r）|1-r|^-3-3(6r^-2的立方根)in which the masses at outside layer are not less than the masses at inside layer, and the solution of this kind of central configuration is unique for the given ratio (b) of masses.     

一类种群动力学模型的概周期解

文应用Liapunov泛函研究一类种群动力学模型概周期解的存在唯一性，推广了已有的相应结果.     

一维连续时间Markov分枝过程的密度演化方程

本文通过建立密度演化方程 ,将一维连续时间Markov分枝过程问题转化为确定性的方法来研究 ,用C0 半群理论证明了密度解的存在性和唯一性 ,并介绍了求密度解及其母函数表达式的方法 ,得到了一些有益的结果     

一类三次系统极限环的惟一性

讨论三次系统x=x(A0+A1x+A2y+A3xy-A4y2)y=y(x-1)的极限环问题.得到了该系统不存在极限环和存在惟一极限环的条件.     

奇异非线性二阶三点边值问题正解的存在唯一性

本文研究了一类奇异非线性二阶三点边值问题，通过摄动技巧和比较原理获得了所论问题正解的存在唯一性。