Banach空间中不连续非线性Volterra型积分方程的唯一解

本文在一般序Ｂａｎａｃｈ空间中研究了不连续非线性Ｖｏｌｔｅｒｒａ型积分方程的唯一解．在非常弱的条件下证明了非线性Ｖｏｌｔｅｒｒａ型积分方程的唯一解可以由迭代序列的一致极限得到,并给出了逼近解的迭代序列的误差估计式,然后应用到一阶微分方程的初值问题,本质改进并推广了最近的一些结果．     

Banac空间不连续非增Volterra型积分方程的迭代唯一解

在非常弱的条件下研究了一般序Banach空间不连续非增Volterra型积分方程的迭代唯一解,并给出了一致收敛于唯一解迭代序列的误差估计式,然后应用到序Banach空间中一阶微分方程的初值问题,本质改进并推广了最近的一些结果。     

Banach空间非线性混合型微分-积分方程整体解的存在性和唯一解

研究了Banach空间中非线性混合型微分-积分方程初值问题u′=f(t,u,Tu,Su),u(0)=x0的整体解,完全没有要求f的任何增性,利用Mnch不动点定理和比较结果得到了初值问题整体解的存在性和唯一解,并且给出了一致收敛于唯一解的迭代序列,改进推广和统一了已有的许多结果.     

Banach空间非线性混合型微分－积分方程的解

本文利用一些新的比较结果研究了Ｂａｎａｃｈ空间中非线性混合型微分积分方程初值问题的最大解和最小解，唯一解以及解的迭代逼近，统一和推广了最近的许多结果。     

Banach空间非线性混合型微分－积分方程的解

本文利用一些新的比较结果研究了Ｂａｎａｃｈ空间中非线性混合型微分积分方程初值问题的最大解和最小解，唯一解以及解的迭代逼近，统一和推广了最近的许多结果。     

Eikonal型方程粘性解的表达式

对于圆锥型和棱锥型Hamiltonian的Eikonal型方程,本文给出了一种几何方法,得出其初值问题解的表达式并且说明由此式给出的解为原初值问题的粘性解．首先用一个凸函数序列逼近Eikonal型方程中的Hamiltonian,再由Hopf-Lax公式给出方程序列的粘性解,最后证明了该粘性解序列会收敛到Eikonal方程的粘性解．     

不连续一阶微分系统广义解的存在唯一性定理和迭代逼近

本文利用混合单调技巧,得到了不连续一阶微分系统初值问题广义解的存在唯一性定理;构造了一致收敛于广义解的迭代序列,且得到了收敛速度的估计式。本文考虑R~n中不连续一阶常微分方程初值问题。     

序Banach空间不连续脉冲积分-微分方程初值问题的解

讨论了序Banach空间不连续脉冲积分-微分方程初值问题,通过建立一个新的比较定理,在比较弱的条件下推广了相关文献的主要结果.并在比较广泛的上控制条件而且只有一个上解或下解的假设下,获得了唯一解的存在性定理,而且给出了迭代序列的误差估计.从而推广并改进了最近某些文献中的相应结果.     

三维Zakharov-Kuznetsov方程解的衰减性

考虑三维Zakharov-Kuznetsov方程的初值问题,证明了该初值问题解的指数衰减性.这个性质与加权Sobolev空间中解的持久性及该问题解的唯一连续性相关.     

Banach空间中微分方程的弱Carathodory解

本文在一般Banach空间中讨论微分方程的初值问题：u＇＝f（t，u），u（0）＝x0．设f（t，u）不连续，仅满足所谓弱Caratheodory条件，但仍证明了初值问题的解可由迭代序列的一致极限得到，并给出了逼近解的迭代序列的误差估计．对周期过值问题得到了类似的结果．     

A unique solution of initial value problems for first order impulsive integro-differential equations of mixed type in Banach spaces

In this paper, we investigate initial value problem for first order impulsive integro-differential equation of mixed type in a Banach space. Without any compactness-type assumption, we obtain a unique solution of the equation, an explicit iterative approximation of the solution and an error estimate of the approximation sequence. Our result improves and extends many recent results.     

一类非线性矩阵方程对称解的双迭代算法

利用逆矩阵的Neumann级数形式,将在Schur插值问题中遇到的含未知矩阵二次项之逆的非线性矩阵方程转化为高次多项式矩阵方程,然后采用牛顿算法求高次多项式矩阵方程的对称解,并采用修正共轭梯度法求由牛顿算法每一步迭代计算导出的线性矩阵方程的对称解或者对称最小二乘解,建立求非线性矩阵方程的对称解的双迭代算法.双迭代算法仅要求非线性矩阵方程有对称解,不要求它的对称解唯一,也不对它的系数矩阵做附加限定.数值算例表明,双迭代算法是有效的.     

TRICOMI PROBLEM FOR A MIXED EQUATION OF SECOND ORDER WITH DISCONTINUOUS COEFFICIENTS

This paper is devoted to the Tricomi problem for a mixed type equation of second order. The coeffcients are assumed to be discontinuous on the line where the type is changed. The unique existence of the solution to the problem is proved if the domain is small enough. Correspondingly, some estimates on the solution is also established.     

On the “Destruction” of Solutions of Nonlinear Wave Equations of Sobolev Type with Cubic Sources

We consider model three-dimensional wave nonlinear equations of Sobolev type with cubic sources, and foremost, model three-dimensional equations of Benjamin-Bona-Mahony and Rosenau types with model cubic sources. An essentially three-dimensional nonlinear equation of spin waves with cubic source is also studied. For these equations, we investigate the first initial boundary-value problem in a bounded domain with smooth boundary. We prove local solvability in the strong generalized sense and, for an equation of Benjamin-Bona-Mahony type with source, we prove the unique solvability of a “weakened” solution. We obtain sufficient conditions for the “destruction” of the solutions of the problems under consideration. These conditions have the sense of a “large” value of the initial perturbation in the norms of certain Banach spaces. Finally, for an equation of Benjamin-Bona-Mahony type, we prove the “failure” of a “weakened” solution in finite time.     

求解矩阵方程AXB+CXD=F参数迭代法的最优参数分析

本文针对求矩阵方程AXB+CXD=F唯一解的参数迭代法，分析当矩阵A，B，C，D均是Hermite正（负）定矩阵时，迭代矩阵的特征值表达式，给出了最优参数的确定方法，并提出了相应的加速算法.     

含高次逆幂的矩阵方程对称解的双迭代算法

本文研究了在控制理论和随机滤波等领域中遇到的一类含高次逆幂的矩阵方程的等价矩阵方程对称解的数值计算问题.采用牛顿算法求等价矩阵方程的对称解,并采用修正共轭梯度法求由牛顿算法每一步迭代计算导出的线性矩阵方程的对称解或者对称最小二乘解,建立了求这类矩阵方程对称解的双迭代算法,数值算例验证了双迭代算法是有效的.     

Successive iterations for unique positive solution of a nonlinear fractional q-integral boundary value problem

In this paper, under certain nonlinear growth conditions, we investigate the existence and successive iterations for the unique positive solution of a nonlinear fractional $q$-integral boundary problem by employing hybrid monotone method, which is a novel approach to nonlinear fractional $q$-difference equation. This paper not only proves the existence of the unique positive solution, but also gives some computable explicit hybrid iterative sequences approximating to the unique positive solution.     

矩阵方程X+A*X-nA=I的正定解

In this paper we give some sufficient conditions and some necessary conditions under which the matrix equation X A^*X^-nA=I has a positive definite solution. An iterative method which converges to a positive definite solution of this equation is constructed. And an error estimate formula on this iterative method is also derived.     

Convergence of hybrid viscosity and steepest-descent methods for pseudocontractive mappings and nonlinear Hammerstein equations

In this article, we first introduce an iterative method based on the hybrid viscosity approximation method and the hybrid steepest-descent method for finding a fixed point of a Lipschitz pseudocontractive mapping (assuming existence) and prove that our proposed scheme has strong convergence under some mild conditions imposed on algorithm parameters in real Hilbert spaces. Next, we introduce a new iterative method for a solution of a nonlinear integral equation of Hammerstein type and obtain strong convergence in real Hilbert spaces. Our results presented in this article generalize and extend the corresponding results on Lipschitz pseudocontractive mapping and nonlinear integral equation of Hammerstein type reported by some authors recently. We compare our iterative scheme numerically with other iterative scheme for solving non-linear integral equation of Hammerstein type to verify the efficiency and implementation of our new method.