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621.
622.
O. V. Leibina 《Mathematical Notes》2007,81(3-4):496-502
We show that if the holomorphic curvature of a complex Grassmann manifold in two-dimensional directions tangent to a nondegenerate Grassmann image of a nonsingular complex surface attains the maximal possible value along all directions, then the surface is a complex hypersurface. 相似文献
623.
624.
本文将计算随机映射图的给定顶点集的任意分类的连接概率及其极限性质,导出随机映射图的连通分支个数的分布与渐进分布. 相似文献
625.
Francesco M. Malvestuto 《Discrete Mathematics》2009,309(13):4287-234
Known properties of “canonical connections” from database theory and of “closed sets” from statistics implicitly define a hypergraph convexity, here called canonical convexity (c-convexity), and provide an efficient algorithm to compute c-convex hulls. We characterize the class of hypergraphs in which c-convexity enjoys the Minkowski-Krein-Milman property. Moreover, we compare c-convexity with the natural extension to hypergraphs of monophonic convexity (or m-convexity), and prove that: (1) m-convexity is coarser than c-convexity, (2) m-convexity and c-convexity are equivalent in conformal hypergraphs, and (3) m-convex hulls can be computed in the same efficient way as c-convex hulls. 相似文献
626.
The concept of fuzzy Galois connections is defined on fuzzy posets with Bělohlávek's fuzzy Galois connections as a special case. The properties of fuzzy Galois connections are investigated. Then the relations between fuzzy Galois connections and fuzzy closure operators, fuzzy interior operators are studied. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
627.
应用数学机械化方法研究欧氏空间中$SU(2)$ Yang-Mills规范场的存在性问题.首先对YM--方程的结构进行了讨论,说明YM--方程由它的奇部份和偶部份联立组成.对于YM--方程构造了一类线性微分变换,称之为$SU(2)$规范场的示性变换.经示性变换,将非线性的YM--方程的奇部份变为一组Laplace方程,实现了$SU(2)$规范场方程的线性化.从而证明了$SU(2)$规范场存在3个独立的Yang-Mills规范场. 相似文献
628.
任新安 《数学物理学报(B辑英文版)》2009,29(2):447-455
In [6], a global solution of Yang-Mills equation on de-Sitter spacetime with conformal fiat metric was given by Prof. Lu. In this article, Yang-Mills equation on ndimensional de-Sitter space with Beltrami-Hua-Lu metric is discussed and a global solution is obtained. 相似文献
629.
K¨ahler Finsler Metrics Are Actually Strongly K¨ahler 总被引:6,自引:1,他引:5
In this paper, the Kahler conditions of the Chern-Finsler connection in complex Finsler geometry are studied, and it is proved that Kahler Finsler metrics are actually strongly Kahler. 相似文献
630.
Cai Tie De‐Wen Zhang Hong‐Xu Chen Sen‐Lin Song Xin‐Xiang Zhang 《Journal of mass spectrometry : JMS》2012,47(11):1429-1434
With the combination of high separation ability of capillary electrophoresis (CE) and strong identification ability of mass spectrometry (MS), CE/MS is becoming a powerful tool for polar and ionic analytes analysis. Different interfaces have been developed to enhance the sensitivity and reliability since the first introduction of CE/MS in 1987. A sheathless porous interface based on a new ions transferring electric connection technique was reported to be with high sensitivity and reliability. In this work, a series of optical and electrochemical experiments were designed to study the electric connection process. The results indicated that closing CE electrical circuit and applying MS spray voltage were achieved by the small ions transferring through the interface porous wall. The new electric connection method significantly enhanced the sensitivity, resolution and stability of the CE/MS analysis. The interface was applied in CE/MS detection of morphine and 6‐monoacetylmorphine in urine sample and showed an equal sensitivity to LC/MS. With the significant improvement of sensitivity and stability, the CE/MS with the new interface showed strong potential for the determination of low abundance analytes. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献