遗传中紧空间与散射分解

本文证明了可数仿紧(中紧、亚紧)空间有类似Junnila的刻画，遗传中紧空间不具有类似Junnila的刻画，并给出了每个散射分解有紧有限的开膨胀的充要条件．     

Products with linear and countable type factors

The basic theorem presented shows that the product of a linearly ordered space and a countable (regular) space is normal. We prove that the countable space can be replaced by any of a rather large class of countably tight spaces. Examples are given to prove that monotone normality cannot replace linearly ordered in the base theorem. However, it is shown that the product of a monotonically normal space and a monotonically normal countable space is normal.

     

Monotone normality and paracompactness

In this paper it is proved that a topological space is necessarily paracompact if it is monotonically normal and any one of the following: screenable, paralindelöf, has a G_δ-diagonal or a quasi-G_δ-diagonal or has a σ-locally-countable base.     

双层空间的刻画

该文利用双g-函数和半连续函数给出了双层空间的刻画,得到:空间(X,Υ_1,Υ_2)是双层当且仅当对于每一个f∈Υ_i-LSC(X),都对应一个h(f)∈Υ_i-LSC(X)∩Υ_j-USC(X)使得(1)0≤h(f)≤f且当f(x)0时,0h(f)(x)f(x).(2)当f≤f′时,h(f)≤h(f′).     

基亚紧空间(英文)

介绍了基亚紧拓扑空间的概念,这类空间是完全亚紧空间类及基仿紧空间类的推广.本文主要研究基亚紧空间的性质,证明了如下结果:(1)每一个可展的亚紧空间是基亚紧空间;(2)基亚紧性在开闭且有限到一的连续映射下保持;(3)若X是两个序数的积空间的子空间,则X是亚紧的当且仅当X是完全亚紧的.     

关于单调亚紧空间

In the first part of this note, we mainly prove that monotone metacompactness is hereditary with respect to closed subspaces and open Fó-subspaces. For a generalized ordered (GO)-space X, we also show that X is monotonically metacompact if and only if its closed linearly ordered extension X* is monotonically metacompact. We also point out that every non-Archimedean space X is monotonically ultraparacompact. In the second part of this note, we give an alternate proof of the result that McAuley space is paracompact and metacompact.     

The Totally Non-positive Matrix Completion Problem

In this paper, the totally non-positive matrix is introduced. The totally non-positive completion asks which partial totally non-positive matrices have a completion to a totally non-positive matrix. This problem has. in general, a negative answer. Therefore, our question is for what kind of labeled graphs G each partial totally non-positive matrix whose associated graph is G has a totally non-positive completion? If G is not a monotonically labeled graph or monotonically labeled cycle, we give necessary and sufficient conditions that guarantee the existence of the desired completion.     

Countable compact Hausdorff spaces need not be metrizable in ZF

We show that the existence of a countable, first countable, zero-dimensional, compact Hausdorff space which is not second countable, hence not metrizable, is consistent with ZF.

     

用优化比较方程的核判别大系统的稳定性

采用K类函数法从非线性大系统集结出损失最小（相对已取得的矢量Lyapunov函数而言）的比较方程（自治非线性的）,并从中取出相对简单的核方程。对后者以单调倾负曲线为脊柱构造了箱体Lyapunov函数,判定了大系统的渐近稳定性。所得判据是核方程已知量的代数显式,便于应用。     

强单调T2空间的几个性质

§1Introduction Theclassofstratifiable(=M3)spacesincludesallmetricspacesandmanytopological groups.Stratifiablespaceholdsmostofthestrongestandusefulpropertiesofmetric space.ThequestionproposedbyCederwhetherstratifiablespaceisM1spaceornotisstill opennow.ManyresearcheshavediscussedthepropertiesofMi(i=1,2,3)spacesthrough monotonenormality(see[2-7]).Borges[6]studiedthemonotonicallynormalproperties,Heath,etal.[5]gavemajorcontributiononmonotonenormality,andBuck,etal.[2]proposedseveraladditionalcha…