仿紧局部cosmic空间的一些性质

给出仿紧局部cosmic空间的一些特征,建立了仿紧局部cosmic空间的几类序列覆盖L映象的特征,证明了闭L映射和商ss映射保持仿紧局部cosmic空间的性质,此外,还给出仿紧局部cosmic空间的一些映射性质。     

关于局部紧空间的闭Lindelf映象

本文给出了两类局部紧空间闭 L (Lindelof)映象的内部特征 ,证明了空间 X是仿紧局部紧空间的闭 L映象当且仅当 X是具有σ-局部有限 k系的 k′空间 ,由此得到在 k′空间类中 ,仿紧局部紧空间的闭 L映象等价于仿紧局部紧空间的商 SL映象 .同时还证明了空间 X是局部紧度量空间的闭 L映象当且仅当 X是具有σ-局部有限紧 k网的 Fréchet空间 .     

关于局部紧空间的闭Lindel(o¨)f映象

本文给出了两类局部紧空间闭L(Lindelf)映象的内部特征,证明了空间X是仿紧局部紧空间的闭L映象当且仅当X是具有σ-局部有限k系的k′空间,由此得到在k′空间类中,仿紧局部紧空间的闭L映象等价于仿紧局部紧空间的商SL映象.同时还证明了空间X是局部紧度量空间的闭L映象当且仅当X是具有σ-局部有限紧k网的Fréchet空间.     

仿紧局部紧空间的序列覆盖L-映象

本文利用特定的覆盖性质,建立了仿紧局部紧空的序列覆盖L－映象和紧覆盖L－映象的特征,得到或深化了局部紧度量空间的一些相应结果。     

关于局部紧空间的闭Lindelof映象

本文给出了两类局部紧空间闭Ｌ（Ｌｉｎｄｅｌｏｆ）映象的内部特征,证明了空间Ｘ是仿紧局部紧空间的闭Ｌ映象当且发Ｘ是具有σ－局部有限ｋ系的ｋ空间,由此得到在ｋ′空间类中,偏紧局部紧空间的闭Ｌ映象等价于偏紧局部紧空间的商ＳＬＪ央象,同时不证明了空间Ｘ是局部紧度量空间的闭Ｌ映象当且Ｘ是具有σ－局部有限紧ｋ网的Ｆｒｅｃｈｅｔ空间。     

仿紧局部可分空间及其映象

探讨仿紧局部可分空间的一些性质,获得了两个可度量化定理,建立了仿紧局部可分空间的各类序列覆盖L-映象的特征。     

关于紧覆盖π映射

本文利用紧有限分解覆盖的概念，给出了度量空间的紧覆盖π象以刻划，并证明了g可度量化空间是度量空间的紧覆盖紧映象．     

局部紧 Lindel(o)f空间的映象

主要借助于紧覆盖映射、闭映射和商映射讨论了局部紧Lindel(o)f空间的像空间,推导出具有某些特定性质的k系空间的一些刻画,引入强k系的概念给出了局部紧Lindel(o)f空间和仿紧局部紧空间的一种新的等价刻画.     

拟仿紧性与乘积空间

本文证明了在V=L假定下,所有正规局部紧拟仿紧空间是仿紧的．并证明了正则拟仿紧性在有限 对一闭映射下是逆保持的．还研究了狭义拟仿紧性的有限乘积和逆极限定理．     

度量空间的序列商,k-映象

本文给出了度量空间序列商．肛映象的-些内部刻画。证明了空间X是度量空间的序列商。肛映象当且仅当X具有紧有限k-闭cs*-覆盖列的点星sn-网，当且仅当X具有紧有限k-闭覆盖列的点星网．作为上述结果的-个推论．不仅得到了空间X是度量空间序列商，k-映象当且仅当X是度量空间的k-映象，而且还证明了空间X是度量空间当且仅当X具有局部有限(紧有限)闭(肛闭)覆盖列的点星弱邻域网．这里“闭”(“k闭”)不能省略．     

Cn中拟凸映射和星形映射的系数问题

§ 1.　Introduction　　Theconvexfunctionshavebeenextensivelystudiedinonecomplexvariable .Thesefunc tionsareeasilycharacterizedbysimpleanalyticorgeometricconditionsandtherearemanywellknownresultswhichcanhelpusunderstandtheirnature.However,thedifficultiesariseinsev eralcomplexvariables.Imposingtheconditionthatamappingbeconvexmappingturnsouttobeveryrestrictiveandsothefamilyofquasi convexmappingswasintroducedbyROPERKAandSUFFRIDGETJin [1 ].In [2 ]wehaveshown :thefamilyofquasi convexmappings…     

THE GROWTH THEOREM FOR QUASI-CONVEX MAPPINGS IN HILBERT SPACES

In this paper, the authors extend the definition of quasi-convex mappings and obtain the corresponding growth theorem.on the unit ball of a complex Hilbert space X.     

The closure of planar diffeomorphisms in Sobolev spaces

We characterize the (sequentially) weak and strong closure of planar diffeomorphisms in the Sobolev topology and we show that they always coincide. We also provide some sufficient condition for a planar map to be approximable by diffeomorphisms in terms of the connectedness of its counter-images, in the spirit of Young's characterisation of monotone functions. We finally show that the closure of diffeomorphisms in the Sobolev topology is strictly contained in the class INV introduced by Müller and Spector.     

A note on sequence-covering mappings

Summary Let f: X → Y be a mapping. f is called a sequence-covering mapping if in case S is a convergent sequence containing its limit point in Y then there is a compact subset K of X such that f(K) = S. It is shown that each quotient and compact mapping of a metric space is sequence-covering.     

C^n中单位球上的强拟凸映照

若记B^n为C^n中的单位球,本文研究B^n上的强拟凸映强,（1）强拟凸映照与星形映照及凸映照的关系,（2）强拟凸映照的二次项系;（3）单位多圆柱上的强拟凸映照。     

New Subclasses of Biholomorphic Mappings and the Modified Roper-Suffridge Operator

The authors propose a new approach to construct subclasses of biholomorphic mappings with special geometric properties in several complex variables. The RoperSuffridge operator on the unit ball B~n in C~n is modified. By the analytical characteristics and the growth theorems of subclasses of spirallike mappings, it is proved that the modified Roper-Suffridge operator [Φ_(G,γ)(f)](z) preserves the properties of S_Ω~*(A, B), as well as strong and almost spirallikeness of type β and order α on B~n. Thus, the mappings in S_Ω~*(A, B), as well as strong and almost spirallike mappings, can be constructed through the corresponding functions in one complex variable. The conclusions follow some special cases and contain the elementary results.     

Boundary behaviour of the mappings satisfying generalized inverse modular inequalities

We study the geometric properties of the mappings for which generalized inverse modular inequalities hold. We generalize in this way known theorems from the theory of analytic mappings and the theory of quasiregular mappings, like the theorems of Fatou, M. and F. Riesz, Beurling and Lindelöf and their extensions given for quasiregular mappings by Martio, Rickman and Vuorinen.     

A note on harmonic quasiconformal mappings

In this note we show that a harmonic quasiconformal mapping f=u+iv with respect to the Poincaré metric of the upper half plane onto itself such that v(x,y)=v(y) or u(x,y)=u(x) is a conformal mapping.     

Compact images of spaces with a weaker metric topology

If X is a space that can be mapped onto a metric space by a one-to-one mapping, then X is said to have a weaker metric topology. In this paper, we give characterizations of sequence-covering compact images and sequentially-quotient compact images of spaces with a weaker metric topology. The main results are that (1) Y is a sequence-covering compact image of a space with a weaker metric topology if and only if Y has a sequence of point-finite cs-covers such that for each y ∈ Y. (2) Y is a sequentially-quotient compact image of a space with a weaker metric topology if and only if Y has a sequence of point-finite cs*-covers such that for each y ∈ Y. Supported by the NNSF(10471084) of China.     

关于局部紧度量空间的映象

本文借助于商映射、伪开映射和闭映射建立局部紧度量空间和几类具有某些特定性质mk-系之间的联系，作为推论.得到：双商ss-映射保持局部紧度量空间.