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1.
In this paper, a class of biholomorphic mappings called complete quasiconvex mappings is introduced and studied in bounded convex Reinhardt domains of ℂ n . Through a detailed analysis of the analytic characterization for this class of mappings, it is shown that this class of mappings contains the convex mappings and is also a subset of the class of starlike mappings. In the special case of the polydisc, a decomposition theorem is established for the complete quasiconvex mappings, which in turn is used to derive an improved sufficient condition for the convex mappings. Translated from Chinese Annals of Mathematics (Series A)  相似文献   

2.
The concepts of almost biased mappings and almost compatible mappings are introduced. Some variants of these concepts are also discussed. A common fixed point theorem for a pair of almost I-biased mappings in metric spaces is proved under certain condition. In the sequel, it is shown that almost biased mappings and almost compatible mappings are equivalent under some condition.  相似文献   

3.
A class of biholomorphic mappings named “quasi-convex mapping” is introduced in the unit ball of a complex Banach space. It is proved that this class of mappings is a proper subset of the class of starlike mappings and contains the class of convex mappings properly, and it has the same growth and covering theorems as the convex mappings. Furthermore, when the Banach space is confined to ℂn, the “quasi-convex mapping” is exactly the “quasi-convex mapping of type A” introduced by K. A. Roper and T. J. Suffridge.  相似文献   

4.
We study a hereditary starlikeness property for planar harmonic mappings on a disk and on an annulus. While such a property is a common trait of conformal mappings, it may be absent in harmonic mappings. It turns out that a sufficient condition for a harmonic mapping f to possess this hereditary property is to have a harmonic argument — a striking feature of conformal mappings that does not extend to all harmonic mappings.  相似文献   

5.
A class of biholomorphic mappings named “quasi-convex mappings of type D” is introduced in the unit ball of a complex Banach space, which is the natural generalization of the convex functions in one variable. It is proved that this class of mappings is a subset of the class of “quasi-convex mappings of type A” introduced by K.A. Roper and T.J. Suffridge.  相似文献   

6.
Summary Recently, Pathak [13] has made an extension of the notion of compatibility to weak compatibility, and extended the coincidence theorem for compatible mappings in Kaneko and Sessa [11] to weakly compatible mappings [13]. In the present paper, we define a new class of weakly compatible mappings (Definition 4) and prove some common fixed point theorems for these mappings, which satisfy Condition (2) below. Although our main theorem is formulated for weakly compatible mappings, its corresponding formulation for commutative mappings is also a new result, thus presenting a generalization of some theorems of Fisher, Das and Naik, Khan and Kubiaczyk, Reich, Ćirić and Rhoades and Watson.  相似文献   

7.
In this paper, we first study the relationship between weakly contractive mappings and weakly Kannan mappings. Further, we discuss characterizations of metric completeness which are connected with the existence of fixed points for mappings. Especially, we show that a metric space is complete if it has the fixed point property for Kannan mappings.

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8.
It is shown that mappings in ℝn with finite distortion of area in all dimensions 1 ≤ kn − 1 satisfy certain modulus inequalities in terms of inner and outer dilatations of the mappings; in particular, generalizations of the well-known Poletskii inequality for quasiregular mappings are proved. The theory developed is applicable, for example, to the class of finitely bi-Lipschitz mappings, which is a natural generalization of the bi-Lipschitz mappings, as well as isometries and quasi-isometries in ℝn.  相似文献   

9.
刘小松  刘太顺 《数学学报》2018,61(6):1029-1036
本文首先给出复Banach空间单位球上一类α次星形映射齐次展开式各项的精细估计,特别当这些映射又是k折对称映射时,估计还是精确的.其次建立C~n中单位多圆柱上上述推广映射齐次展开式各项的精细估计,同样当这些映射又是k折对称映射时,估计仍是精确的.由此证明了多复变数中关于α次星形映射的弱Bieberbach猜想,且所得到的估计都能回到单复变数的情形.  相似文献   

10.
Two problems are solved: the obtaining of hyperbolicity conditions for families of individual multidimensional mappings and applying these hyperbolicity conditions to a system of coupled mappings and the subsequent proof of the preservation of the hyperbolicity property for the important class of coupled mappings considered. The study is performed by using one-dimensional “comparison mappings” and by introducing a metric special for this class of mappings. It is essential that the hyperbolicity conditions are formulated in terms of conditions for a concrete class of functions defining the mappings. __________ Translated from Sovremennaya Matematika i Ee Prilozheniya (Contemporary Mathematics and Its Applications), Vol. 33, Suzdal Conference-2004, Part 1, 2005.  相似文献   

11.
给出图闭模糊映射和闭模糊映射的关系:图闭模糊映射一定是闭模糊映射;若闭模糊映射是上半连续的则它也是图闭模糊映射.  相似文献   

12.
In this paper, our main aim is to introduce the concept of planar p-harmonic mappings and investigate the properties of these mappings. First, we discuss the p-harmonic Bloch mappings. Two estimates on the Bloch constant are obtained, which are generalizations of the main results in Colonna (1989) [9]. As a consequence of these investigations, we establish a Bloch and Landau's theorem for p-harmonic mappings.  相似文献   

13.
本文提出了广义A-proper映射,它更弱于A-proper映射。通过建立广义A-proper度,可用来研究(M)型映射与部分解答Browder问题(见[4];用类似[6]的方法)。本文推广了[3]、[6]和[2]的工作。 今往设X、y为实Banach空间,D X是开集。D表其边界,是之闭包。“→”和“”分别表强和弱收敛。N为正整数集合。  相似文献   

14.
We study limit mappings from a solenoid onto itself. It is shown that each equivalence class of finite-sheeted covering mappings from connected topological spaces onto a solenoid is determined by a limit mapping. Properties of periodic points of limit mappings are also studied.

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15.

Considering two classes of Hölder mappings of Carnot-Carathéodory spaces, graph mappings and smooth mappings in the Riemannian sense, we obtain an area formula for image surfaces. In particular, we describe the structure of the polynomial sub-Riemannian differential for graph mappings.

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16.
ON A SURJECTIVITY FOR THE SUM OF TWO MAPPINGS OF MONOTONE TYPE   总被引:2,自引:0,他引:2  
In this paper the sum(T+S)of two nonlinear mappings is considered,where T ismaximal monotone or generalized pseudomonotone and S is generalized pseudomonotone orof type(M).By using the concepts of T-boundedness,T-generalized pseudomonotonemappings and mappings of type T--(M) introduced by the author,it is proved that(T+S) is of type (M).A new surjectivity result for multivalued pseudo A-propermappings is given.As a consequence,it is obtained that the coercive mappings of type(M)whose effective domain contains a dense linear subspace are surjectivity. In particular,the author answers affirmatively a part of Browder's question(see[1],p.70).  相似文献   

17.
Summary In this paper we consider several classes of mappings related to the class of contraction mappings by introducing a convexity condition with respect to the iterates of the mappings. Several fixed point theorems are proved for such mappings. Further, in a similar way we consider a related class of mappings satisfying a convexity condition with respect to diameters of bounded sets. In the last part we consider classes of mappings on PM- spaces (probabilistic metric spaces of K. Menger) and some fixed point theorems are given for such classes.  相似文献   

18.
Banach空间中几乎渐近非扩张型映象的不动点的迭代逼近   总被引:6,自引:0,他引:6  
曾六川 《应用数学和力学》2003,24(12):1258-1266
在Banach空间中引入了一类新的几乎渐近非扩张型映象,概括了Banach空间中若干熟知的非线性的Lipschitz映象类与非Lipschitz映象类成特例;例如,熟知的非扩张映象类,渐近非扩张映象类与渐近非扩张型映象类.考虑了用于逼近几乎渐近非扩张型映象不动点的带误差的修改了的Ishikawa迭代序列的收敛性问题.关于Banach空间范数的S.S.Chang的不等式与H.K.Xu的不等式皆被用于做精确不动点与近似不动点间的误差估计.而且,张石生教授用于做带误差的修改了的Ishikawa迭代序列收敛性分析的方法(应用数学和力学,2001,22(1):23-31)被推广到几乎渐近非扩张型映象的情况.给出了用于求一致凸Banach空间中几乎渐近非扩张型映象不动点的带误差的修改了的Ishikawa迭代序列的新的收敛判据.并且,由该判据,立即得到了此类映象的带误差的修改了的Mann迭代序列的新的收敛判据.上述结果统一、改进与推广了张石生教授关于用带误差的修改了的Ishikawa与Mann迭代序列来逼近渐近非扩张型映象不动点方面的结果.  相似文献   

19.
This paper deals with fuzzy-set-valued mappings of the real line, and more particularly focuses on mappings from the real line to the set of convex normal fuzzy sets of the real line. These mappings can also be viewed as fuzzy relations. Using Zadeh's extension principle, the integral of such fuzzy mappings over a crisp interval is defined. Provided a special analytical representation of the fuzzy mapping, the practical computation of such an integral is shown to be easy. Practically speaking, it yields the fuzzy surface of a fuzzily-bounded area.  相似文献   

20.
Robert C. Powers 《Order》1990,7(1):83-96
The purpose of this paper is to introduce a class of mappings from a lattice L, whose elements are residuated maps, into itself. The main results of this paper identify certain injective residuated mappings of L and order automorphisms of a sublattice of L with mappings from this class.  相似文献   

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