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141.
This work deals with the spectral analysis of set-valued operators from a Banach space X into its dual space X*. The main goal of the paper is to study semicontinuity properties of the spectrum operator.Mathematics Subject Classifications (2000) 47H04, 47H12, 58C40.UMR 2071 Universidad de Chile-CNRS. 相似文献
142.
本文对含非局部源反应扩散方程的定常问题讨论了正解的存在性,对依赖时间的解,给出了整体存在条件和有限时间爆破条件。 相似文献
143.
图和线图的谱性质 总被引:5,自引:0,他引:5
陈晏 《高校应用数学学报(英文版)》2002,17(3):371-376
Let G be a simple connected graph with n vertices and m edges,Lo be the line graph of G and λ1(LG)≥λ2 (LG)≥...≥λm(LG) be the eigenvalues of the graph LG,.. In this paper, the range of eigenvalues of a line graph is considered. Some sharp upper bounds and sharp lower bounds of the eigenvalues of Lc. are obtained. In oarticular,it is oroved that-2cos(π/n)≤λn-1(LG)≤n-4 and λn(LG)=-2 if and only if G is bipartite. 相似文献
144.
本文研究复射影空间CP^n和四元数射影空间QP^n中的紧致极小超曲面,对其上Jacobi算子的最小特征值给出了一个最佳上界估计,由此给出了CP^n和QP^n中广义赤道的一个新的特征。 相似文献
145.
徐利光 《新疆大学学报(理工版)》2005,22(4):416-424
运用C0-半群理论研究一类由可修,可靠的人与机器构成的系统解的渐近性质.首先证明在虚轴上除了0以外其他所有点都属于该算子的豫解集,其次证明0是对应于该系统的主算子及其共轭算子的几何与代数重数为1的特征值,由此推出该系统的时间依赖解当时刻趋向于无穷时强收敛于系统的稳态解. 相似文献
146.
Lilia Yu. Kolotilina 《Numerical Algorithms》2006,42(3-4):247-280
Using a unified approach based on the monotonicity property of the Perron root and its circuit extension, a series of exact two-sided bounds for the Perron root of a nonnegative matrix in terms of paths in the associated directed graph is obtained. A method for deriving the so-called mixed upper bounds is suggested. Based on the upper bounds for the Perron root, new diagonal dominance type conditions for matrices are introduced. The singularity/nonsingularity problem for matrices satisfying such conditions is analyzed, and the associated eigenvalue inclusion sets are presented. In particular, a bridge connecting Gerschgorin disks with Brualdi eigenvalue inclusion sets is found. Extensions to matrices partitioned into blocks are proposed. 相似文献
147.
Metastable dynamics for a nonlocal PDE modeling the upwards propagation of a flame-front interface in a vertical channel is analyzed in the one-dimensional case where the channel cross-section is taken to be the slab -1<x<1. In a certain asymptotic limit, the interface assumes a roughly concave parabolic shape, and the tip of the parabola drifts asymptotically exponentially slowly towards the boundary of the domain. In contrast to previous analyses that studied this behavior by transforming the governing nonlocal PDE to a convection–diffusion equation, a novel nonlinear transformation is introduced that transforms the problem to a singularly perturbed quasilinear PDE. The steady-state problem for this transformed PDE, for which the parabolic interface shape maps onto a one-spike solution, is closely related to a class of two-point boundary value problems with seemingly spurious solutions studied initially by G. Carrier in 1968. Rigorous and formal asymptotic results for a one-spike solution to this transformed PDE are obtained together with a formal metastability analysis of certain time-dependent solutions. 相似文献
148.
A formulation is given for the spectral transformation of the generalized eigenvalue problem through the decomposition of the second-order differential operators. This allows us to construct some Laurent biorthogonal polynomial systems with gaps in the degree of the polynomial sequence. These correspond to an exceptional-type extension of the orthogonal polynomials, as an extension of the Laurent biorthogonal polynomials. Specifically, we construct the exceptional extension of the Hendriksen–van Rossum polynomials, which are biorthogonal analogs of the classical orthogonal polynomials. Similar to the cases of exceptional extensions of classical orthogonal polynomials, both state-deletion and state-addition occur. 相似文献
149.
150.
GREEN'SFUNCTIONSOFTWO-DIMENSIONALANISOTROPIC BODY WITH A PARABOLIC BOUNDARY(胡元太)(赵兴华)GREEN'SFUNCTIONSOFTWO-DIMENSIONALANISOTROP?.. 相似文献