ON SYMMETRIC SCALAR CURVATURE ON

1.IntroductionGivenacontinuousfunctionRonthestandardsphereS',itisaninterestingproblemwhetherRcanbethescalarcurvatureofsomemetricgwhichispointwiseconformaltothestandardmetricgoonS2.Ifwesetg~e"go,whereuisafunctiononS',theproblemisequivalenttothesolvabilityofthefollowingPDE:--A..u 2--Re"=0,onS2.(l'1)KazdanandWarner[9]pointedoutthatitmaybeinsolvable.Inthelastfewyears,alotofworkhasbeendonetosolveproblem(l.l),especiallywhenRpossessessomekindsofsymmetries.AfterthepioneerworkduetoMoser[lo]forthe…     

BOUNDS ON COINCIDENCE INDICES ON NON-ORIENTABLE SURFACES

§ 1 . IntroductionQuestions about bounds for indices ?rst appeared in the ?xed point context. The ?rstresults appeared in studies of surface homeomorphisms (see [13, 18, 19]). In [12, 14] and[15] some results about bounds for Nielsen ?xed point class ind…     

限制参数空间上的Fiducial推断

给出了在限制参数空间上,利用Fiducial方法求参数的区间估计的一般方法,并且讨论了一些常见的典型问题,结果表明所得的区间估计是合理的．另外,本文还证明了在限制参数空间上,刻度族和位置族中参数的条件Fiducial分布与无信息先验的Bayes 后验分布一致,推广了Lindely的结论．     

关于曲面无穷小等距的两个定理

本文研究了一类曲面的无穷小Ⅰ（Ⅲ）—等距，得到了两个整体定理，并由此证明了在适当的边界条件下，特殊Ｗｅｉｎｇａｒｔｅｎ曲面Ｍ的无穷小Ⅰ（Ⅲ）—等距Φ是关于Ｍ的无穷小刚体运动。     

关于复平面有界闭集上的有理函数逼近

给出了复平面有界闭集的壳与有理函数的可逼近性之间的关系定理。     

ON BAND IRREDUCIBLE OPERATORS ON BANACH LATTICES

Abstract

In this note we prove an extension of B. de Pagter's theorem (positive, compact, irreducible operators on Banach lattices are not quasi-nilpotent) for positive, band irreducible operators on Banach lattices satisfying some additional conditions.     

两个安全第一思想模型的比较分析

针对投资者可能的投资需求确立了基于安全第一思想下两个相近的投资目标:1、极大化投资末期总收益率超过给定水平α的概率;2、极小化投资末期总收益率与给定水平α的距离.并分别就这两个目标建立了优化决策模型,得到了模型解析解,最后对两个模型结果进行了比较分析和经济解释.     

ON THE BOTTLENECK CAPACITY EXPANSION PROBLEMS ON NETWORKS

This article considers a class of bottleneck capacity expansion problems. Such problems aim to enhance bottleneck capacity to a certain level with minimum cost. Given a network G(V, A, C) consisting of a set of nodes V= {v1,v2,…,vn},a set of arcs A ■ {(vi, vj) | i=1,2,…, n;j=1,2,…,n} and a capacity vector C. The component cij of C is the capacity of arc (vi ,vj). Define the capacity of a subset A' of A as the minimum capacity of the arcs in A, the capacity of a family F of subsets of A is the maximum capacity of its members. There are two types of expanding models. In the arc-expanding model, the unit cost to increase the capacity of arc (vi, vj) is wij. In the node-expanding model, it is assumed that the capacities of all arcs (vi,vj) which start at the same node vi should be increased by the same amount and that the unit cost to make such expansion is wi. This article considers three kinds of bottleneck capacity expansion problems (path, spanning arborescence and maximum flow) in both expanding models. For each kind of expansion problems, this article discusses the characteristics of the problems and presents several results on the complexity of the problems.     

关于G逆半群的同余格

本文讨论Ｇ逆半群上的同余,文中给出刻划ｐ＾ｋ,ｐｋ,ｐ＾Ｔ,ｐＴ的方法,并用来讨论半格同余,纯幂同余,群同余及幂等元分离同余。     

ON MAŞEK'S CRITERION ON VERY AMPLENESS

ABSTRACT

In this note, we give a new proof of Ma?ek's criterion on very ampleness of adjoint linear systems on surfaces and prove very ampleness for certain polarized threefolds.     

关于余极限范畴(英文)

本文研究了余极限范畴.利用余完备Abel范畴的定义,证明了余完备Abel范畴A的余极限范畴Acl是余完备的Abel范畴,并得到一类等价于模范畴的余极限范畴,从而推广了文献[9]中的一些结果.     

关于k-映射

本文给出度量空间ｋ－映象的一些新的特征。证明了ｋ－映射保持一些具有某种特定性质的点可数覆盖的空间。     

关于时标上的适应Nabla分数阶导数

本文研究了时标上的适应Nabla分数阶导数的问题.利用时标理论,获得了关于适应Nabla分数阶导数的若干重要性质.这些结果推广并改进了文献[9,10]中的有关结论以及一般Nabla导数的性质.     

ON THE

本文旨在系统阐述Weaker Γ     

关于D-空间

本文研究了用邻域对应定义的空间类.利用构造性的方法,证明了有限多个狭义拟仿紧空间的并是aD-空间及λ-半层空间是D-空间,得到了拓扑空间是aD-空间或D-空间的充分条件,一般化了已有的相应结果.     

ON TWIN-TRIANGULAR ADDITIVE GROUP ACTIONS ON C4

This paper concerns some of the conditions satisfied by additive group actions on complex affine space which can be written locally as a translation of a variable. Assume X is the affine variety C ⁿ , G_a = (C, +), and σ : G_a × X → X is the action defined by a group monomorphism G _a → Aut _C X. If σ is locally trivial, then the action satisfies what is termed a “GICO” condition.

It will be shown that a large class of G_a -actions on C ⁴, that is, fixed-point free, “twin-triangular” actions with finitely-generated rings of invariants, are at least GICO. Remaining questions are discussed.     

ON TOPOLOGICAL LINEAR CONTRACTIONS ON NORMED SPACES AND APPLICATION

51.IntroductionandPreliminariesThroughoutthispaper(X,11'if)denotesanormedspaceandN(11'II)denotesthecollectionofallnormsonXwhichareequivalentto11'11.Foreach11'if'6N(II'II)andeachr>0,letX.(ll'II')~{xEX:Ilxll'5r}andX?(ll'if')~{xEX.Ilxll'相似文献   

极小超曲面上Laplace算子的谱

本文证明了单位球面Ｓ＾ｎ＋１中某些Ｃｌｉｆｆｏｒｄ超曲面，复射影空间和四元数射影空间中广ＹＱ ＬＩＦＦＯＲＤＦＨＶ ＭＡ ＤＭ Ｊ ＭＨ ＡＤＷ Ｈ Ｌａｐｌａｃｅ算子的谱唯一确定。     

ON EFFECTIVE NON-VANISHING OF WEIL DIVISORS ON ALGEBRAIC SURFACES

The author gives a counterexample and some conclusions for effective non-vanishing of Weil divisors on algebraic surfaces.