一类非线性椭圆方程正解的存在性

研究了一类非线性椭圆方程. 应用改进型Hardy不等式和变分方法, 证明了在一定条件下方程正解的存在性.     

抽象空间中非线性算子方程变号解的存在性研究

利用Banach空间中的锥理论和不动点定理讨论了非线性算子方程变号解的存在性,给出了E_u_0空间下非线性算子方程变号解至少有一个变号解、一个正解和一个负解的条件,并讨论了仅通过一个上解条件得出非线性算子方程变号解的存在性定理.     

具连续变量差分方程的比较定理及强迫振动

本文首先给出了具连续变量常系数线性差分方程存在正解的充要条件,然后利用它得出了带阻尼项的变系数差分方程振动的充分条件．     

带有临界指数的椭圆方程多重正解的存在性

采用变分方法考虑了一类带有临界指数和有限个奇点的椭圆方程正解的存在性问题,利用临界点理论可以得到V(x)的每一个奇点都可以产生一个正解.     

奇异椭圆方程多重解的存在性

在这篇论文中,首先给出了奇异椭圆方程(1.1)正解在零点附近的一个精确的估计.然后,结合这个估计式,利用Ekeland变分原理和山路引理,在一定条件下得到了方程(1.1)多重正解的存在性.     

一类带变号权函数的p-Kirchhoff方程正解的存在性与多解性

利用变分方法,通过对Nehari流形进行分解,证明了一类带变号权函数的pKirchhoff方程正解的存在性与多解性.     

具有奇性的非线性椭圆方程的边值问题

本文研究奇异椭圆方程的边值问题．利用变分方法和锥理论中的混合单调方法,证明了奇异方程正解的存在性、唯一性     

一类奇异椭圆方程的正解

研究一类奇异椭圆方程问题。利用变分方法和锥理论中的混合单调方法,证明了奇异方程正解的存在性。     

具有奇性的非线性椭圆方程的边值问题

本文研究奇异椭圆方程的边值问题.利用变分方法和锥理论中的混合单调方法,证明了奇异方程正解的存在性、唯一性.     

一阶变系数中立型方程正解的存在性和渐近性

一阶变系数中立型方程正解的存在性和渐近性李万同（甘肃张掖师专数学系张掖７３４０００）权宏顺（兰州大学数学系兰州７３００００）关键词：中立型方程；正解存在性；渐近性ＡＭＳ（１９９１）主题分类：３４Ｃ１０．考虑一阶变系数中立型时滞微分方程（ｘ（ｔ）一ｅｘ...     

Global Existence of Positive Solutions for Volterra Integral Equations

ＧｌｏｂａｌＥｘｉｓｔｅｎｃｅｏｆＰｏｓｉｔｉｖｅＳｏｌｕｔｉｏｎｓｆｏｒＶｏｌｔｅｒｒａＩｎｔｅｇｒａｌＥｑｕａｔｉｏｎｓＷａｎｇＳｈｕ（王术）；ＷａｎＣｈｕｎｌｉｎ（万春林）；ＺｈａｎｇＫｕｎ（张锟）（ＨｅｍａｎＵｎｉｖｅｒｓｉｔｙ，Ｋａｉｆｅｎ...     

Positive fixed points for a class of nonlinear operators and applications

In this paper, we study the existence and uniqueness of positive solutions for a class of nonlinear operator equations on ordered Banach spaces. Various applications are also considered to illustrate our obtained results (existence of solutions to quadratic integral equations with a linear modification of the argument, positive solution of second-order Neumann boundary value problem, and positive definite solutions of a class of nonlinear matrix equations).     

分数阶微分方程m点边值问题正解的存在性

应用凸锥上的不动点定理,讨论了一类分数阶微分方程m点边值问题正解的存在性,得到了这类边值问题至少存在一个正解的充分条件,并给出了一个实例.     

A class of discrete time generalized Riccati equations

In this paper, a class of discrete-time backward non-linear equations defined on some ordered Hilbert spaces of symmetric matrices is considered. The problem of the existence of some global solutions is investigated. The class of considered discrete-time non-linear equations contains, as special cases, a great number of difference Riccati equations both from the deterministic and the stochastic framework. The results proved in the paper provide the sets of necessary and sufficient conditions that guarantee the existence of some special solutions of the considered equations as: the maximal solution, the stabilizing solution and the minimal positive semi-definite solution. These conditions are expressed in terms of the feasibility of some suitable systems of linear matrix inequalities (LMI). One shows that in the case of the equations with periodic coefficients to verify the conditions that guarantee the existence of the maximal or the stabilizing solution, we have to check the solvability of some systems of LMI with a finite number of inequations. The proofs are based on some suitable properties of discrete-time linear equations defined by the positive operators on some ordered Hilbert spaces chosen adequately. The results derived in this paper provide useful conditions that guarantee the existence of the maximal solution or the stabilizing solution for different classes of difference matrix Riccati equations involved in many problems of robust control both in the deterministic and the stochastic framework. The proofs are deterministic and are accessible to the readers less familiarized with the stochastic reasonings.     

Banach空间半线性发展方程的周期解

把上、下解方法引入到有序Ｂａｎａｃｈ空间中的半线性发展方程周期解问题，利用正算子半群特征与单调迭代程序，获得了最大周期解与最小周期解的存在性．所得的结果概括和推广了常微分方程与偏微分方程中的有关结论     

Existence and uniqueness of positive solutions of semilinear elliptic equations

This paper is devoted to the study of existence,uniqueness and non-degeneracy of positive solutions of semi-linear elliptic equations.A necessary and sufficient condition for the existence of positive solutions to problems is given.We prove that if the uniqueness and non-degeneracy results are valid for positive solutions of a class of semi-linear elliptic equations,then they are still valid when one perturbs the differential operator a little bit.As consequences,some uniqueness results of positive solutions under the domain perturbation are also obtained.     

Positive solutions for Neumann elliptic problems involving critical Hardy–Sobolev exponent with boundary singularities

In this paper we consider the existence of positive solution for some semilinear elliptic equations with Neumann boundary condition involving a critical Hardy–Sobolev exponent and Hardy terms with boundary singularities. Using mountain pass lemma without (PS) condition and the strong maximum principle, we get the existence of a positive solution.     

Existence of positive solutions for a class of higher-order nonlinear fractional differential equations with integral boundary conditions and a parameter

In this paper, we study the existence of positive solutions for a class of higher-order nonlinear fractional differential equations with integral boundary conditions and a parameter. By using the properties of the Green’s function, u ₀-positive function and the fixed point index theory, we obtain some existence results of positive solution under some conditions concerning the first eigenvalue with respect to the relevant linear operator. The method of this paper is a unified method for establishing the existence of multiple positive solutions for a large number of nonlinear differential equations of arbitrary order with any allowed number of non-local boundary conditions.     

渐近线性算子方程的四种类型的解

利用拓扑度理论及不动点指数理论,讨论了渐近线性算子方程的四种类型的解(即零解、正解、负解和变号解)的存在性,并将这一抽象结果应用于微分方程两点边值问题.     

Symmetric positive solutions for second order boundary value problems with integral boundary conditions on time scales

This paper investigates the existence of symmetric positive solutions for a class of nonlinear boundary value problem of second order dynamic equations with integral boundary conditions on time scales. Under suitable conditions, the existence of symmetric positive solution is established by using monotone iterative technique