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931.
In this paper, a class of biholomorphic mappings named quasi-convex mapping of order α in the unit ball of a complex Banach space is introduced. When the Banach space is confined to Cn, we obtain the relation between this class of mappings and the convex mappings.Furthermore, the growth and covering theorems of this class of mappings are given on the unit ball of a complex Banach space Ⅹ. Finally, we get the second order terms coefficient estimations of the homogeneous expansion of quasi-convex mapping of order α defined on the polydisc in Cn and on the unit ball in a complex Banach space, respectively. 相似文献
932.
Alexandros Patsourakos 《Letters in Mathematical Physics》1998,45(3):269-276
In this Letter we characterize Lie elements and the elements of the kernel of the Lie bracketing from right to left mapping, using tensor calculus tools. 相似文献
933.
V. A. Krasnov 《Mathematical Notes》1998,63(6):747-751
Two Picard numbers and two Lefschetz numbers are defined for a real algebraic surface. They are similar to the Picard number and the Lefschetz number of a complex algebraic surface. For these numbers, some estimates and relations in the form of inequalities are proved.Translated fromMatematicheskie Zametki, Vol. 63, No. 6, pp. 847–852, June, 1998. 相似文献
934.
群体决策的偏差度分析 总被引:16,自引:2,他引:14
本文引进群体决策的决策个体和决策群体关于两方案的偏差度,以及群体偏差映射的概念.在建立相应的偏差公理的基础上,研究了群体决策偏差分析的基本理论.同时,还给出一个利用偏差度进行群体排序的方法. 相似文献
935.
Paul F. Fewster 《固体与材料科学评论》1997,22(2):69-110
This review covers the recent advances in reciprocal space mapping. The experimental techniques as well as the theoretical and conceptual developments are discussed. The advantages of reciprocal space mapping over the conventional single scan X-ray scattering methods become clear from the examples presented. Extracting the additional information from mapping in reciprocal space maps has led to a deeper understanding of materials. Imperfect materials benefit enormously from these methods. Near perfect materials also indicate weak diffuse scattering that can now be interpreted in terms of defects, etc., whereas with single scans the influence is difficult to observe and separate from other features. Reciprocal space maps can be collected with both high and low angular resolution diffractometers, depending on the application, although a combination of resolutions may be necessary. It is also growing in importance in the analysis of materials using specular reflectometry. High-resolution reciprocal space mapping is not restricted to good crystalline quality. Examples of reciprocal space mapping are given for semiconductors, metals, ceramics and biological samples. For semiconductor materials, reciprocal space mapping has now become almost routine in the study of lattice relaxation in thin layers and in the assessment of the “quality” of materials. Combinations of mapping with topography and precision lattice parameter determination are also discussed. The latter part of this review discusses the advantages of three-dimensional reciprocal space mapping, which takes the analysis further. With this method the full three-dimensional shapes in reciprocal space can be studied. 相似文献
936.
度量空间的序列商,k-映象 总被引:1,自引:1,他引:0
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. 相似文献
937.
Yinying Kong 《Journal of Mathematical Analysis and Applications》2008,344(2):1158-1164
Using Ahlfors' covering surface method, some properties on Borel radius of meromorphic functions with finite order in the unit circle are obtained. The main object of this paper is to prove the existence of filling discs in Borel radius of such functions, which briefly extends the results of A. Rauch. 相似文献
938.
The authors first give the definition of degenerate weakly (K1,K2)-quasiregular mappings using the technique of exterior power and exterior differential forms, and then, using the method of McShane extension, a useful inequality is obtained, which can be used to derive the self-improving regularity. 相似文献
939.
The authors discuss the proper holomorphic mappings between special Hartogs triangles of different dimensions and obtain a corresponding classification theorem. 相似文献
940.
Jing ZHANG 《数学年刊B辑(英文版)》2008,29(5)
In this paper, a result on the persistence of lower dimensional invariant tori in Cd reversible systems is obtained under some conditions. The theorem is proved for any d which is larger than some constants. 相似文献