序列式MESO紧空间的闭Lindelof逆象(英文)

证明了正则空间中闭Lindelof映射逆保持序列式meso紧性,从而改进了Mancuso V J关于正则空间中完备映射逆保持meso紧性这一结果;进一步我们指出定理条件中原象空间的正则性不可被省略而象空间的正则性可以用原象空间的正规性来替代.     

一个除数问题的推广

本文推广了Ｒ．Ａ．Ｓｍｉｔｈ，Ｍ．Ｖ．Ｓｕｂｂａｒａｏ和Ｇ．Ｎｏｗａｋ所考虑的一个除数问题．令Ｓ＝｛（ａｉ，ｑｉ）｜ａｉ≤ｑｉ｝（ｒ≥３）．定义ｄ（ｎ；Ｓ）＝Σ（１）１，Σ（１）表示对满足ｎ＝ｍ１…ｍｒ，ｍｊ≡ａｊ（ｍｏｄｑｊ），ｊ＝１，２，…，ｒ的诸ｍｊ求和．我们求出了Σｎ≤ｘｄ（ｎ；Ｓ）的渐近公式，并得到了余项估计．     

On the Weight of Nowhere Dense Subsets in Compact Spaces

We study a new cardinal-valued invariant ndw(X) (calling it the nd-weight of X) of a topological space which is defined as the least upper bound of the weights of nowhere dense subsets of X. The main result is the proof of the inequality hl(X)ndw(X) for compact sets without isolated points ((hl is the hereditary Lindelof number). This inequality implies that a compact space without isolated points of countable nd-weight is completely normal. Assuming the continuum hypothesis, we construct an example of a nonmetrizable compact space of countable nd-weight without isolated points.     

Moore机器的若干应用

本文利用Ｇ．Ｍ．Ｒｅｅｄ构造的Ｍｏｏｒｅ机器证明了：（１）Ｍｏｏｒｅ空间中的弱Ｌｉｎｄｅｌｏｆ住严格介于ＣＣＣ与ＤＣＣＣ之间．（２）强星可遮的Ｍｏｏｒｓ空间不必是星仿紧的．     

The exit time of planar Brownian motion and the Phragmén–Lindelöf principle

In this paper a version of the Phragmén–Lindelöf principle is proved using probabilistic techniques. In particular, we will show that if the p  th moment of the exit time of Brownian motion from a planar domain is finite, then an analytic function on that domain is either bounded by its supremum on the boundary or else goes to ∞ along some sequence more rapidly than e^|z|2p$e^{{|z|}^{2p}}$. We also provide a method of constructing domains whose exit time has finite pth moment. This allows us to give a general Phragmén–Lindelöf principle for spiral-like and star-like domains, as well as a new proof of a theorem of Hansen. A number of auxiliary results are presented as well.     

Pseudocompact, Locally Compact, First Countable, ccc, 0-dimensional Spaces May Be or May Not Be Lindelof

We construct a pseudocompact, locally compact, first countable, 0-dimensional,eec, non- Lindelof space under the assumption CH or the existence of a Suslin line. Butunder MA+CH, such a space cannot exist.     

Metric σ-Frames versus Metric Lindelof Spaces

The adjoint relation between the category RegFrm, of regular -frames, Alex, of Alexandroff spaces, are studied in [9]. Here, we introduce the category MFrm, of metric -frames and give the adjoint relation between this category and the category MLSp, of metric Lindelof spaces, and show that MLSp is dually equivalent to the category of Alexandroff metric -frames.AMS Subject Classification: 06D99-54B30     

A Property of Solutions for Elliptic Equation with Nonstandard Growth Conditions in Unbounded Domain

§０．　ＩｎｔｒｏｄｕｃｔｉｏｎＬｅｔΩｂｅａｎｕｎｂｏｕｎｄｅｄｄｏｍａｉｎｉｎｔｈｅｎ－ｄｉｍｅｎｓｉｏｎａｌＥｕｃｌｉｄｅａｎｓｐａｃｅＥｎ（ｎ３）．Ｃｏｎｓｉｄｅｒ－ｉｎｇｔｈｅｆｏｌｌｏｗｉｎｇｅｌｌｉｐｔｉｃｅｑｕａｔｉｏｎｗｉｔｈｎｏｎｓｔａｎｄａｒｄｇｒｏｗｔｈｃｏｎｄｉｔｉｏｎｓ：－ｄｉｖＡ（ｘ,ｕ,ｕ）＝Ｂ（ｘ,ｕ,ｕ）（１）ｗｈｅｒｅＡ（ｘ,ｕ,ξ）＝｛Ａｉ（ｘ,ｕ,ξ）,ｉ＝１,２,…,ｎ｝ａｎｄＢ（ｘ,ｕ,ξ）ａｒｅｄｅｆｉｎｅｄｏｎＥｎ×Ｅ１×Ｅｎ,ｃｏｎ－…     

关于submeso紧空间的映射定理

证明了在正则空间中闭Lindelof映射保持且逆保持submeso紧性,这改进了林寿关于正则空间完备映射保持且逆保持submeso紧性这一结果;同时我们引用一个反例说明原象空间的正则性是必要的.     

关于相邻素数差之和的上界估计

设P_n表第n个素数,d_n=P_(n+1)-P_n.设0≤u≤1,令S_》(x)=∑d_n.P_n≤xd_n≥x~"再设f(弘)表最小的值使得对任意的c〉0,S_y(x)=0(x~(f(")+h)),x→∞.本文利用Heath-Brown引进的N(口,T)及其估计,得到了S_。(x)的新的估计,同时在Lindelof假设下作出新的估计.