Projections on weak*-closed subspace of dual Banach algebras

Our first purpose in this paper is to provide necessary conditions for a weak*-closed translation invariant subspace in the semigroup algebra of a locally compact topological foundation semigroup to be completely complemented. We give conditions when a weak*-closed left translation invariant subspace in Ma(S)* of a compact cancellative foundation semigroup S is the range of a weak*-weak* continuous projection on M _a (S)* commuting with translations. Let G be a locally compact group and A be a Banach G-module. Our second purpose in this paper is to study some projections on A* and B(A*) which commutes with translations and convolution.     

一致连续映射的两个扩张定理

把文[1],[2]中的两个定理进行了拓广和改进,给出两个一致连续映射的扩张定理:(i)任一集合A到一个完备度量空间的一致连续映射可一致连续扩张到A珡上.(ii)任一闭集A到Rn的一致连续映射可一致连续扩张到A与任一紧集的并.     

紧框架中的Korovkin型定理

关于线性正算子的Korovkin 定理在函数逼近理论中是著名的定理, 本文将建立几个关于紧框架的Korovkin 型定理.     

Banach空间分数阶微分方程的多个正解

利用全连续算子的不动点指数理论获得了Banach空间中分数阶微分方程多个正解的存在性.     

混合系数线性模型的几乎无偏岭估计

本文研究了连续测量数据情况下的混合系数线性模型的参数估计问题.利用岭估计方法得到了该模型的几乎无偏岭估计,并证明了在均方误差意义下,几乎无偏岭估计优于岭估计.最后讨论了有偏参数的选取问题.     

Almost Sure Central Limit Theorem for Partial Sums of Markov Chain

The authors prove an almost sure central limit theorem for partial sums based on an irreducible and positive recurrent Markov chain using logarithmic means,which realizes the extension of the almost sure central limit theorem for partial sums from an i.i.d.sequence of random variables to a Markov chain.     

Rigid Properties of Quasi-almost-Einstein Metrics

In this paper,quasi-almost-Einstein metrics on complete manifolds are studied.Two examples are given and several formulas are established.With the help of these formulas,the author proves rigid results on compact or noncompact manifolds,in which some basic tools,such as the weighted volume comparison theorem and the weak maximum principle at infinity,are used.A lower bound estimate for the scalar curvature is also obtained.     

A Characterization of Topologically Transitive Attributes for a Class of Dynamical Systems

In this work,by virtue of the properties of weakly almost periodic points of a dynamical system (X,T) with at least two points,the authors prove that,if the measure center M(T) of T is the whole space,...     

Kolmogorov-Tamarkin紧性定理的推广

本文研究了Kolmogorov-Tamarkin的紧性问题.利用鞅收敛定理,获得了任意测度空间上的Lp空间中紧集的判别准则,推广了Lp(Rd,dx)集合为紧集的Kolmogorv-Tamarkin准则.     

单位球上的加权Bergman空间到加权Bloch空间的积分型算子

本文主要研究单位球上加权Bergman空间到加权Bloch空间的积分型算子的性质.利用符号函数和权函数,给出了积分型算子P9(Φ)的有界性和紧性的特征,推广了相关结果.