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1.
该文讨论一般非均匀凸介质所确定的迁移算子的广义本征函数系统的完整性问题,利用我们探索的相对收敛方法,完整地刻划了一般非均匀凸介质中迁移问题的广义本征函数系统的完整性问题,我们证明了,对迁移半群E(t),当0∈Pσ(E(t)),迁移算子广义本征函数系统不完整,当0∈Pσ(E(t))时,仅当满足相对收敛条件时,迁移算子的广义本征函数系统完整.  相似文献   

2.
近来S.Reich对予解式相容性(Consistency)的问题,以及其他与此有关的问题,得到了较好的结果(见文[1],定理2.1和文[2]定理1).本文的目的是对Reich的结果进一步加强和改进。具体说我们得到予解式的收敛关于参数入是一致的。 §1.某些予备知识  相似文献   

3.
本文得到具有实际背景的一类C0半群的渐近展开,它仅要求予解式满足一定条件.  相似文献   

4.
集中阻尼弦本征解的性质   总被引:1,自引:0,他引:1       下载免费PDF全文
利用Dirac δ函数,在全域建立并求解集中阻尼弦的动力学方程,导出其本征方程组、频率方程和本征函数的一般形式,推导了单项阻尼下本征函数的具体形式,并分析了中点阻尼对本征解的影响.同时,讨论了混合动力学系统在频率 阻尼关系、衰减率和完全抑制振动的最优阻尼3个方面既不同于连续系统,又不同于离散系统的特性:1)系统频率与其阻尼无关;2)各阶本征函数在单位时间内的衰减率都相同,衰减率与本征值的阶次无关;3)当阻尼取2时,系统衰减率趋于无穷大,系统不能发生任何有阻尼振动.  相似文献   

5.
本文运用矩阵多元多项式的带余除法把双参数弹性地基上正交各向异性矩形薄板的振动方程转化为Hamilton系统,利用分离变量给出对应的Hamilton算子.通过计算得到对边简支问题所对应Hamilton算子的本征值和本征函数系,并证明了该本征函数系的辛正交性和在Cauchy主值意义下的完备性.根据本征函数系的完备性,得到对应Hamilton系统的通解,进而给出双参数弹性地基上正交各向异性矩形薄板对边简支振动问题振型函数的通解.此外,通过两个例子说明此方法可以计算出自由振动问题的频率和振型函数.  相似文献   

6.
本文讨论阻尼振动系统(离散或连续系统)在周期外激励作用下的强迫响应;系统的阻尼阵不能对角化.导出了强迫响应一般解的显式解析表达式.利用这些解式,本文对某些振动现象作了较普遍的解析讨论.如,从一般角度讨论了单阻尼振动系统特有的“固定振幅点”现象;讨论了同相位外激励作用下产生同相位响应的条件等等.本文导出的解式对一大类系统仅含很低阶的矩阵求逆运算,因而在计算机数值计算上.本方法比之于现有方法,具有程序简单、耗时少和精度高等优点.本方法可平行应用于转子动力学的不平衡响应分析.  相似文献   

7.
设X为Banach空间,T(t)为X上的(1,A)类半群,A为T(t)的无穷小母元,若对每个x∈X,映射t→T(t)x关于t>t_0可微,则称T(t)关于t>t_0可微,本文讨论了关于t>t_0可微的(1,A)类半群的若干性质,并利用可微半群母元豫解式的增长阶特征证明了关于t>t_0可微的(1,A)类半群是指数稳定的充分必要条件为sup{Reλ:λ∈σ(A)}<0.  相似文献   

8.
弹性平面扇形域问题及哈密顿体系   总被引:12,自引:4,他引:8  
钟万勰 《应用数学和力学》1994,15(12):1057-1066
通过变量代换及变分原理,将平面弹性扇形域的方程导向哈密顿体系,从而可用分离变量法、本征函数展开等方法求解扇形域的分析单元,这样便可以与有限元的程序系统相结合。显示了哈密顿体系、辛数学的应用潜力。  相似文献   

9.
给出求解基于应力形式的二维弹性问题的本征函数展开方法.通过引入适当的状态函数,将该问题的基本偏微分方程等价地转化为上三角微分系统,导出相应的上三角算子矩阵.证明了该矩阵的两个对角块算子均具有规范的正交本征函数系,并得到它们在相应空间中的完备性.此外,基于本征函数系的完备性,应用本征函数展开法给出了二维弹性问题的一般解.  相似文献   

10.
本文研究了一类本征函数及其梯度的对称二阶椭圆本征值问题的混合有限元法.利用对本征值、本征函数及其梯度的混合有限元误差,得到了本征函数及其梯度的L2(Ω)模和L∞(Ω)模估计.并且给出了数值算例,验证了理论分析.  相似文献   

11.
This paper is the second in a series of several works devoted to the asymptotic and spectral analysis of an aircraft wing in a subsonic air flow. This model has been developed in the Flight Systems Research Center of UCLA and is presented in the works by A. V. Balakrishnan. The model is governed by a system of two coupled integrodifferential equations and a two parameter family of boundary conditions modeling the action of the self-straining actuators. The differential parts of the above equations form a coupled linear hyperbolic system; the integral parts are of the convolution type. The system of equations of motion is equivalent to a single operator evolution-convolution equation in the energy space. The Laplace transform of the solution of this equation can be represented in terms of the so-called generalized resolvent operator, which is an operator-valued function of the spectral parameter. This generalized resolvent operator is a finite-meromorphic function on the complex plane having the branch cut along the negative real semi-axis. Its poles are precisely the aeroelastic modes and the residues at these poles are the projectors on the generalized eigenspaces. In the first paper and in the present one, our main object of interest is the dynamics generator of the differential parts of the system. It is a nonselfadjoint operator in the energy space with a purely discrete spectrum. In the first paper, we have shown that the spectrum consists of two branches and have derived their precise spectral asymptotics. In the present paper, we derive the asymptotical approximations for the mode shapes. Based on the asymptotical results of these first two papers, in the next paper, we will discuss the geometric properties of the mode shapes such as minimality, completeness, and the Riesz basis property in the energy space.  相似文献   

12.
The purpose of this paper is to introduce a new system of generalized resolvent equations with corresponding system of variational inclusions in uniformly smooth Banach spaces. We establish an equivalence relation between system of generalized resolvent equations and system of variational inclusions. The iterative algorithms for finding the approximate solutions of system of generalized resolvent equations are proposed. The convergence of approximate solutions of system of generalized resolvent equations obtained by the proposed iterative algorithm is also studied.   相似文献   

13.
Aslam Noor  Muhammad 《Positivity》1997,1(2):145-154
In this paper, we introduce and study a new class of variational inequalities, which is called the generalized mixed variational inequality. Using essentially the resolvent operator concept, we establish the equivalence between the generalized mixed variational inequalities and the system of resolvent equations. This equivalence is used to suggest a number of new iterative algorithms for solving the variational inequalities. Several special cases are discussed which can be obtained from the main results of this paper.  相似文献   

14.
In this paper, we study the well‐posedness of a coupled Darcy–Oseen resolvent problem, describing the fluid flow between free‐fluid domains and porous media separated by a semipermeable membrane. The influence of osmotic effects, induced by the presence of a semipermeable membrane, on the flow velocity is reflected in the transmission conditions on the surface between the free‐fluid domain and the porous medium. To prove the existence of a weak solution of the generalized Darcy–Oseen resolvent system, we consider two auxiliary problems: a mixed Navier–Dirichlet problem for the generalized Oseen resolvent system and Robin problem for an elliptic equation related to the general Darcy equations. © 2016 The Authors Mathematical Methods in the Applied Sciences Published by John Wiley & Sons Ltd.  相似文献   

15.
In this paper, we use the constancy of certain subspace valued mappings on the components of the generalized Kato resolvent set and the equivalences of the single-valued extension property at a point 0 for operators which admit a generalized Kato decomposition to obtain a classification of the components of the generalized Kato resolvent set of operators. We also give some applications of these results.  相似文献   

16.
In this paper, we develop the sensitivity analysis for generalized set-valued variational inclusions and generalized resolvent equations. We establish the equivalence between the parametric generalized set-valued variational inclusions and parametric generalized resolvent equations, by using the resolvent operator technique without assuming the differentiability of the given data.  相似文献   

17.
In this paper,we first introduce a new class of generalized accretive operators named(H,η)-accretive in Banach space.By studying the properties of(H,η)-accretive,we extend the concept of resolvent operators associated with m-accretive operators to the new(H,η)-accretive operators.In terms of the new resolvent operator technique,we prove the existence and uniqueness of solutions for this new system of variational inclusions.We also construct a new algorithm for approximating the solution of this system and discuss the convergence of the sequence of iterates generated by the algorithm.  相似文献   

18.
It is well known in the field of radiative transfer that Sobolev was the first to introduce the resolvent into Milne's integral equation with a displacement kernel. Thereafter it was shown that the resolvent plays an important role in the theory of formation of spectral lines. In the theory of line-transfer problems, the kernel representation in Milne's integral equation has been used to provide an approximate solution in a manner similar to that given by the discrete ordinales method.In this paper, by means of invariant imbedding we show how to determine an exact solution of a Milne-type integral equation with a degenerate kernel, whose form is more general than the Pincherle-Gourast kernel. A Cauchy system for the resolvent is expressed in terms of generalized Sobolev's Φ- and Ψ-functions, which are computed by solving a system of differential equations for auxiliary functions. Furthermore, these functions are expressed in terms of components of the kernel representation.  相似文献   

19.
广义混合似变分不等式组的两步迭代算法   总被引:1,自引:0,他引:1  
对H ilbert空间中一类广义混合似变分不等式组进行了研究;利用次微分算子的预解式技术,建立了广义混合似变分不等式组与不动点问题之间的等价关系;给出了一个求解这种广义混合似变分不等式组的显式两步迭代算法;并证明了该算法在适当的条件下收敛.  相似文献   

20.
In this paper, we consider a generalized mixed equilibrium problem in real Hilbert space. Using the auxiliary principle, we define a class of resolvent mappings. Further, using fixed point and resolvent methods, we give some iterative algorithms for solving generalized mixed equilibrium problem. Furthermore, we prove that the sequences generated by iterative algorithms converge weakly to the solution of generalized mixed equilibrium problem. These results require monotonicity (θ-pseudo monotonicity) and continuity (Lipschitz continuity) for mappings.  相似文献   

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