包络半群与拓扑动力学中的接近关系

运用包络半群的理论，对接近关系中一个重要定理给出了一个简单证明．作为这一定理的应用，我们得到接近关系可乘性的一个结果．并且对另一种接近关系，也得到一个结果．这两个定理减弱了Ｃｌａｙ在这一领域中两个定理的条件．     

一类Schrodinger方程的周期解和谱方法

本文利用半群理论讨论了一类非线性非自共轭Ｓｃｈｒｏｄｉｎｇｅｒ方程周期初边值解的存在唯一性，以及它的Ｆｏｕｒｉｅｒ谱方法的可解性，稳定性和收敛性     

Stability of <Emphasis Type="Italic">C</Emphasis>-regularized Semigroups

Let T = (T(t))t≥0 be a bounded C-regularized semigroup generated by A on a Banach space X and R(C) be dense in X. We show that if there is a dense subspace Y of X such that for every x ∈ Y, σu(A, Cx), the set of all points λ ∈ iR to which (λ - A)^-1 Cx can not be extended holomorphically, is at most countable and σr(A) N iR = Ф, then T is stable. A stability result for the case of R(C) being non-dense is also given. Our results generalize the work on the stability of strongly continuous senfigroups.     

Non-linear Semigroup of a Class of Abstract Semilinear Functional Differential Equations with a Non-Dense Domain

In this work, we are concerned with a general class of abstract semilinear autonomous functional differential equations with a non-dense domain on a Banach space. Our objective is to study, using the Crandall-Liggett approach, the solutions as a semigroup of non-linear operators.     

Nonlinear Boundary Stabilization of Nonuniform Timoshenko Beam

In this paper, the stabilization problem of nonuniform Timoshenko beam by some nonlinear boundary feedback controls is considered. By virtue of nonlinear semigroup theory, energy-perturbed approach and exponential multiplier method, it is shown that the vibration of the beam under the proposed control actiondecays exponentially or in negative power of time t as t→∞.     

图的不可收缩性和end-正则性

图的半群理论是图的群理论的延伸．图的不可收缩性和end－正则性是其中受到普遍关注的课题．本文揭示了两者之间的内在联系．     

唯一分解整半群上的Mobius函数及其反演公式

陈兆斗首先在文献[1]中定义出了有单位元并满足消去律的唯一分解交换半群上的Mbius函数.本文我们首先证明了Mbius函数作为半群(M1,*)上的元素是常值函数ζ(·)的逆函数.其后获得了该Mbius函数的一些相关结果并给出了三个Mbius反演公式.     

半群的(λ,μ)-Ω-直觉模糊内(双)理想

在模糊集的基础上,把直觉模糊集,Ω-模糊集相结合来研究半群,给出半群中(λ,μ)-Ω-直觉模糊内(双)理想的定义并研究它们的性质。在同态前提下,研究了(λ,μ)-Ω-直觉模糊内(双)理想的像与原像。最后在定义半群(S^Ω,?)的基础上,研究它上的(λ,μ)-直觉模糊内(双)理想与(λ,μ)-Ω-直觉模糊内(双)理想的关系。     

关于半群局部化的一个注记

证明了对于任何的半群Ｓ和其任何的子半群Ｔ，Ｓ在Ｔ的局部化总是存在的。     

Weak Uniform Normal Structure and Fixed Points of Asymptotically Regular Semigroups

Let X be a Banach space with a weak uniform normal structure and C a non–empty convexweakly compact subset of X. Under some suitable restriction, we prove that every asymptoticallyregular semigroup T = {T(t) : t ∈¸ S} of selfmappings on C satisfying

${\mathop {\lim \inf }\limits_{S \mathrel\backepsilon t \to \infty } }{\left| {{\left\| {T(t)} \right\|}} \right|} < {\text{WCS}}(X)$

has a common fixed point, where WCS(X) is the weakly convergent sequence coefficient of X, and\({\left| {{\left\| {T(t)} \right\|}} \right|}\) is the exact Lipschitz constant of T(t).