一个非局部方程解的存在性

本文旨在讨论一个线性非局部方程和相应非线性方程解存在的条件，对非局部积分核作一定限制后，得到在积分核变号条件下解的存在唯一性结果。     

非线性规划问题的精确增广Lagrange函数

对于一般的非线性规划给出一种精确增广Lagrange函数,并讨论其性质.无需假设严格互补条件成立,给出了原问题的局部极小点与增广Lagrange函数在原问题的变量空间上的局部极小的关系.进一步,在适当的假设条件下,建立了两者的全局最优解之间的关系.     

带有非局部条件二阶微分包含的可控性

研究了一类带有非局部条件二阶微分包含的可控性,在多值函数F(t,x)取凸情形下讨论了上述问题,建立了可控性的充分条件.本文将所讨论的问题转化为集值积分算子的不动点问题,利用Kakutani不动点定理得到可控性.     

非线性双曲型微分方程非局部奇摄动问题

本文研究了一类具有非线性双曲型微分方程非局部奇摄动问题．在适当的条件下,讨论了问题解的渐近性态．     

非局部边界条件下的抛物型偏微分方程组

本文首先讨论了一个非局部边界条件下的抛物型偏微分方程组,通过一个变量替换,使得在更宽松的边界假设条件下证明了解的存在唯一性;然后讨论了一个完全非线性的抛物型方程组,同样,通过变量替换证明了比较原理.     

非局部条件下半线性微分方程的适度解

讨论了Banach空间中非局部条件下半线性微分方程的适度解的存在性,利用不动点和非紧测度的方法,给出了在不需要半群紧性条件下方程适度解的存在性,并且对f是连续紧算子和f是Lipschitz连续的情形做了统一处理,从而得到了更为广泛和一般性的结果.     

具有非局部条件的半线性中立型测度方程

在强连续半群紧和非紧的条件下,使用Schauder不动点定理和Krasnoselselskii不动点定理,分别得到了Banach空间中具有非局部条件的半线性中立型测度方程适度解的存在性.     

Banach空间中一类非局部脉冲微分包含的解

在紧半群条件下,讨论具有非局部条件的脉冲算子微分包含解的存在性.利用集值映射不动点定理,在非线性项和非局部项不具有紧性和Lipschitz连续性的框架下研究这一问题,所需的条件更为一般化,得到的结果改进了已有文献中的结论.     

非光滑非凸多目标规划解的充分条件

Kuhn-Tucker型条件的充分性一直是最优化理论中引人注意的一个问题.本文对非光滑函数提出了几个非凸概念,然后,讨论了非光滑非凸多目标规划中Kuhn-Tucker型条件和Fritz John型条件的充分性,在很弱的条件下,建立了一系列充分条件.     

非稠定分数次微分方程在非局部条件下解的存在性(英文)

本文利用积分半群理论,Krasnoselskii不动点定理与压缩映象原理研究了非稠定分数次发展方程在非局部条件下积分解的存在性与唯一性.     

Nonlocal semi-linear fractional-order boundary value problems with strip conditions

This paper is concerned with the question of existence of solutions for one-dimensional higher-order semi-linear fractional differential equations supplemented with nonlocal strip type boundary conditions. The nonlocal strip condition addresses a situation where the linear combination of the values of unknown function at two nonlocal points, located to the left and right hand sides of the strip, respectively, is proportional to its strip value. The case of Stieltjes type strip condition is also discussed. Our results, relying on some standard fixed point theorems are supported with illustrative examples.     

非局部非对称弹性理论混合边值问题的提法

从完全的虚功和虚功率原理以及广义Ｐｉｏｌａ定理出发一并推导出非局部非对称弹性理论的运动方程、所有边界条件和全能量方程。把这时给出的边界条件和高键,戴天民的相应结果加在一超即可表述非局部非对称线性弹性理论的混合边值问题。     

Application and Implementation of Incorporating Local Boundary Conditions into Nonlocal Problems

We study nonlocal equations from the area of peridynamics, an instance of nonlocal wave equation, and nonlocal diffusion on bounded domains whose governing equations contain a convolution operator based on integrals. We generalize the notion of convolution to accommodate local boundary conditions. On a bounded domain, the classical operator with local boundary conditions has a purely discrete spectrum, and hence, provides a Hilbert basis. We define an abstract convolution operator using this Hilbert basis, thereby automatically satisfying local boundary conditions. The main goal in this paper is twofold: apply the concept of abstract convolution operator to nonlocal problems and carry out a numerical study of the resulting operators. We study the corresponding initial value problems with prominent boundary conditions such as periodic, antiperiodic, Neumann, and Dirichlet. To connect to the standard convolution, we give an integral representation of the abstract convolution operator. For discretization, we use a weak formulation based on a Galerkin projection and use piecewise polynomials on each element which allows discontinuities of the approximate solution at the element borders. We study convergence order of solutions with respect to polynomial order and observe optimal convergence. We depict the solutions for each boundary condition.     

Nonlocal Boundary-Value Problems for Elliptic Systems in Angles

In this paper we consider elliptic systems in plane angle with nonlocal boundary conditions. We prove the existence and uniqueness of the solution in weighted space. For a proof, we study a system of ordinary differential equations with a parameter and nonlocal boundary conditions.     

A Peano-Like Theorem for Stochastic Differential Equations with Nonlocal Sample Dependence

The existence of a not-necessarily-unique strong solution for a stochastic differential equations with nonlocal sample dependence is established under the assumption that the coefficients satisfy an asymptotically local boundedness condition in addition to continuity. The proof is by an Euler-like construction of approximations. These equations include mean-field stochastic differential equations, but the nonlocal sample dependence can be more general than just the dependence on moments of the solution.     

Results on Nonlocal Boundary Value Problems

In this article, we provide a variational theory for nonlocal problems where nonlocality arises due to the interaction in a given horizon. With this theory, we prove well-posedness results for the weak formulation of nonlocal boundary value problems with Dirichlet, Neumann, and mixed boundary conditions for a class of kernel functions. The motivating application for nonlocal boundary value problems is the scalar stationary peridynamics equation of motion. The well-posedness results support practical kernel functions used in the peridynamics setting.

We also prove a spectral equivalence estimate which leads to a mesh size independent upper bound for the condition number of an underlying discretized operator. This is a fundamental conditioning result that would guide preconditioner construction for nonlocal problems. The estimate is a consequence of a nonlocal Poincaré-type inequality that reveals a horizon size quantification. We provide an example that establishes the sharpness of the upper bound in the spectral equivalence.     

具有非局部边界条件的奇摄动反应扩散问题

本文研究了一类具有非局部边界条件的奇摄动反应扩散初始边值问题．在适当的条件下，利用比较定理讨论了问题解的渐近性态．     

Singular Perturbation in a Nonlocal Diffusion Problem

We study a singular perturbation problem for a nonlocal evolution operator. The problem appears in the analysis of the propagation of flames in the high activation energy limit, when admitting nonlocal effects.

We obtain uniform estimates and we show that, under suitable assumptions, limits are solutions to a free boundary problem in a viscosity sense and in a pointwise sense at regular free boundary points.

We study the nonlocal problem both for a single equation and for a system of two equations.

Some of the results obtained are new even when the operator under consideration is the heat operator.     

Family of self-adjoint Nonlocal finite-difference schemes

We study the stability of a family of self-adjoint finite-difference schemes for the heat equation with nonlocal boundary conditions. Self-adjointness permits one to use general stability theorems for two-layer finite-difference schemes in energy spaces and consider finite-difference schemes for equations with variable coefficients.     

非局部反应扩散方程奇摄动问题

本文研究了一类具有非局部奇摄动反应扩散初始边值问题.在适当的条件下,利用比较定理讨论了问题解的渐近性态.