Exponential Stability of Semigroups Related to Operator Models in Mechanics

In this paper, we consider equations of the form , where is a function with values in the Hilbert space , the operator B is symmetric, and the operator A is uniformly positive and self-adjoint in . The linear operator generating the C ₀-semigroup in the energy space is associated with this equation. We prove that this semigroup is exponentially stable if the operator B is uniformly positive and the operator A dominates B in the sense of quadratic forms.     

非线性二元算子方程组的迭代求解方法

Using the cone and partial ordering theory and mixed monotone operator theory, the existence and uniqueness of solutions for some classes of systems of nonlinear two binary operator equations in a Banach space with a partial ordering are discussed. And the error estimates that the iterative sequences converge to solutions are also given. Some relevant results of solvability of two binary operator equations and systems of operator equations are improved and generalized.     

线性算子方程广义解的存在性

本文中我们研究并得到了线性算子方程的Moore-Penrose广义解的稳定性性质。     

二元非混合单调算子方程组的迭代求解

利用锥与半序理论和混合单调算子理论,讨论Banach空间中非单调二元非线性算子方程组解的存在性与唯一性,并给出了收敛于方程组解的迭代序列和误差估计。改进和推广了混合单调算子方程和一元算子方程的某些相应结果。     

常系数非齐次线性差分方程的算子解法

本文利用算子方法 ,解决了常系数非齐次线性差分方程的特解问题 .     

随机非线性凝聚算子方程的随机解

利用随机拓扑度理论研究随机非线性凝聚算子,在一定条件下得到随机算子方程A（w,x）=μx的随机解和随机算子不动点的存在性,所得结论减弱了已知文献中相应定理的条件．     

非单调算子方程组解的存在唯一性及其应用

在Banach空间中不具有连续性和紧性的条件下讨论了一类非单调算子方程组解的存在唯一性及迭代收敛性,并且应用到Hammerstein型积分方程中．     

Dynamical System Method for Solving Ill-Posed Operator Equations

Two dynamical system methods are studied for solving linear ill-posed problems with both operator and right-hand nonexact. The methods solve a Cauchy problem for a linear operator equation which possesses a global solution. The limit of the global solution at infinity solves the original linear equation. Moreover, we also present a convergent iterative process for solving the Cauchy problem.     

A Class of Operator Equations in Nonlinear Mechanics

A nonlinear evolution equation in Hilbert space is introduced and is shown to govern a broad class of problems of nonlinear solid mechanics. The simplest oscillations of this equation are described by a “generalized Liénard equation.”

AMS(MOS) Classification Nos: 73D35, 73F15, 58D25, 35L35, 34G20, 34C15.     

On the Spectrum of Degenerate Operator Equations

We study the distribution in the complex plane of the spectrum of the operator , generated by the closure in of the operation originally defined on smooth functions with values in a Hilbert space satisfying the Dirichlet conditions . Here and A is a model operator acting in . Criterial conditions on the parameter for the eigenfunctions of the operator to form a complete and minimal system as well as a Riesz basis in the Hilbert space H are given.     

Banach空间一类H-增生算子的混合拟变分包含的邻近算子方程

本文在Banach空间中引入一类H-增生算子的混合拟变分包含,并提出求该变分包含问题解的邻近点法.通过H-增生算子的预解算子技术,建立了混合拟变分包含问题与邻近算子方程的等价关系,由这个等价关系得到求解邻近算子方程的迭代算法,该算法收敛于上述混合拟变分包含问题的解.     

微分方程的指数稳定性

比较系统地研究了It方程解的指数稳定性.给出了随机指数稳定性、指数P-稳定性、几乎必然指数稳定性的比较准则,这些比较准则推广了Nevel’son和Has’minskiǐ的相应结果.     

Solution Estimates for Nonlinear Nonautonomous Evolution Equations in Spaces with Normalizing Mappings

Nonlinear nonautonomous evolution equations in a space with a normalizing mapping (a generalized norm) are considered. Solution estimates are established. In particular cases these estimates generalize the Wazewski and Lozinskii estimates from the theory of ordinary differential equations. By the obtained estimates, the following problems are investigated: asymptotic stability, boundedness of solutions, input-output stability, existence of periodic solutions. Applications to integro-differential equations are discussed.     

Banach空间中非光滑算子方程的光滑化拟牛顿法

研究Banach空间中非光滑算子方程的光滑化拟牛顿法.构造光滑算子逼近非光滑算子,在光滑逼近算子满足方向可微相容性的条件下,证明了光滑化拟牛顿法具有局部超线性收敛性质.应用说明了算法的有效性.     

一类非单调算子方程解的存在性定理

运用锥理论与非对称迭代方法,得到了Banach空间不具有单调性、连续性和紧性条件的一类算子方程解的存在唯一性,并给出了迭代序列收敛于解的误差估计.所得结果改进和推广了增(减)算子方程的某些已知结果.     

一类非线性二元算子方程的迭代求解及其应用

运用锥与半序理论与混合单调算子理论,讨论半序Banach空间一类非线性二元算子方程解的存在唯一性,并给出迭代序列收敛于解的误差估计.作为应用,讨论了不具有单调性的算子方程的可解性,所得结果是某些已有结果的本质改进和推广.     

Banach空间中半光滑算子方程的不精确牛顿法(英文)

本文主要解决Banach空间中抽象的半光滑算子方程的解法.提出了两种不精确牛顿法,它们的收敛性同时得到了证明.这两种方法可以看作是有限维空间中已存在的解半光滑算子方程的方法的延伸.     

解第一类线性算子方程的多层次迭代法(英文)

In this paper we develop two multilevel iteration methods for solving linear systems resulting from the Galerkin method and Tikhonov regularization for linear ill-posed problems. The two algorithms and their convergence analyses are presented in an abstract framework.     

非线性非单调二元算子方程组的解及其应用

利用非线性泛函分析中的锥理论和单调迭代的方法,研究了一类非线性非单调二元算子方程组的解的存在性,并给出了收敛于解的迭代序列,然后作为应用,得到了B anach空间中的一类非线性V olterra型积分方程组的解,改进了最近的许多结果.     

Some Properties of Periodic Words

In the paper, it is proved that the cube of a simple word cannot be decomposed into the product of words with periods of smaller length. In addition, the decomposition of a simple word's square into the product of words with shorter periods is studied. The interest in this sort of statements stems from the investigation of groups and semigroups specified by periodic defining relations.