On certain spectral properties of a quadratic self-adjoint matrix pencil with dominating main diagonals

Sufficient conditions for the “separation of the spectrum” of a quadratic matrix pencil with self-adjoint coefficients are found. A criterion for the representability of a positive operator in a finite-dimensional space in the form of a matrix with dominating main diagonal in each orthonormal basis is obtained. Translated fromMatematicheskie Zametki, Vol. 61, No. 3, pp. 381–390, March, 1997. Translated by A. I. Shtern     

Quaternionic Killing Spinors

In [17] we proved a lower bound for the spectrum of the Dirac operator on quaternionic Kähler manifolds. In the present article we study the limiting case, i.e. manifolds where the lower bound is attained as an eigenvalue. We give an equivalent formulation in terms of a quaternionic Killing equation and show that the only symmetric quaternionic Kähler manifolds with smallest possible eigenvalue are the quaternionic projective spaces.     

A domain decomposition method for linear exterior boundary value problems

In this paper, we present a domain decomposition method, based on the general theory of Steklov-Poincaré operators, for a class of linear exterior boundary value problems arising in potential theory and heat conductivity. We first use a Dirichlet-to-Neumann mapping, derived from boundary integral equation methods, to transform the exterior problem into an equivalent mixed boundary value problem on a bounded domain. This domain is decomposed into a finite number of annular subregions, and the Dirichlet data on the interfaces is introduced as the unknown of the associated Steklov-Poincaré problem. This problem is solved with the Richardson method by introducing a Dirichlet-Robin-type preconditioner, which yields an iteration-by-subdomains algorithm well suited for parallel computations. The corresponding analysis for the finite element approximations and some numerical experiments are also provided.     

非线性RL电路的暂态特性

对一个可解的非线性ＲＬ电路模型的暂态过程进行了研究，得到非线性ＲＬ电路的一些普遍特性，加深了加ＲＬ电路中的有关概念的理解，对教学有一定的参考价值。     

关于Lipschitz强增生算子的迭代程序

本文在一般的Ｂａｎａｃｈ空间中讨论Ｌｉｐｓｃｈｉｔｚ强增生算子方程解和严格伪压缩算子不动点的迭代逼近问题．我们的结果统一和推广了Ｄｅｎｇ，Ｌｉｕ，Ｔａｎ和Ｘｕ的结果，完整地回答了Ｃｈｉｄｕｍｅ提出的公开问题．     

Spectrum of the Three-Particle Schrödinger Difference Operator on a Lattice

For a three-particle operator on a lattice, we study the properties of its spectrum that depend on pairwise interactions and are determined by a parameter characterizing the intensity of interaction.     

一类线性非自伴算子的谱

近年来国际上出现了一类以迁移理论为背景的所谓＂ｕ－标算子（ｕ－ｓｃａｌａｒｏｐｅｒａｔｏｒ）＂．本文研究ｕ－标算子与经典的标型谱算子（ｓｐｅｃｔｒａｌｏｐｅｒａｔｏｒｏｆｓｃａｌａｒｔｙｐｅ）的内在联系，给出了此类算子的谱与其无界投影族之间的关系，证明了该类算子的剩余谱是空集．     

一类共振条件下的高阶p-Laplacian算子多点边值问题

主要讨论了下列n阶带p-Laplacian算子多点边值问题在共振条件下解的存在性.(Φp(x(n-1)))′+f(t,x,x′,…,x(n-2))=0,0相似文献   

具有负指数系数的微分算子的谱

本文研究了形如∑_n~k=o~((α_k)(e~((α_k)x))D~k(a_k≤0)及∑_k~n=o((-1)~k)α_(2k)D~ke~(α_(2k)x)D~k+i/2∑_k~n=o(α_(2k+1))(D~ke~((α_(2k+1))x)D~(k+1)+D~(k+1)e~((α_(2k+1)x)D~k)(α_k≤0)的算式的谱问题,分别得到了它们的本质谱或本质谱所在的范围.     

Bounds on convex reliability functions with known first moments

In this paper, upper and lower bounds are derived for convex reliability functions (or survival functions) with known first n moments. The case where the mean and the variance are given (n = 2) is discussed in details and explicit expressions are provided. Extensions for n ? 3 moments are described. Comparisons with existing bounds are performed.