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71.
72.
A method for generalizing the notion of orthogonality to arbitrary partially ordered groups is considered. In the paper, the properties of almost orthogonal elements in Riesz groups are investigated. A series of results on convex directed subgroups associated with a pair of almost orthogonal elements of a Riesz group is obtained. For these subgroups, some theorems on homomorphisms are proved. 相似文献
73.
一类具有无穷时滞的Logistic方程的正概周期解存在性与渐近性 总被引:3,自引:0,他引:3
利用李雅普诺夫泛函解决了George Seifert在1996年所提公开问题. 相似文献
74.
Goda Hiroshi; Hirasawa Mikami; Yamamoto Ryosuke 《Proceedings London Mathematical Society》2001,83(2):472-492
Let R be a Seifert surface obtained by applying Seifert's algorithmto a connected diagram D for a link L. In this paper, lettingD be almost alternating, we give a practical algorithm to determinewhether L is a fibered link and R is a fiber surface. We furthershow that L is a fibered link and R is a fiber surface for Lif and only if R is a Hopf plumbing, that is, a successive plumbingof a finite number of Hopf bands. It has been known for sometime that this is true if D is alternating, and we show thatit is not always true if D is 2-almost alternating. In the appendix,we partially answer C. Adams's open question concerning almostalternating diagrams. 2000 Mathematical Subject Classification:57M25. 相似文献
75.
1 IntroductionEquationor its nonhomogeneous formwhere p, q) r and w are constants, originated with the study of aerodinamica.And then as its generalization, forced Rayleigh equationespecially its periodic solution has been studied by many authors. For example,R.Reissig [1], proved equation (1.1) has at least one w-periodic solution underthe following conditionsi) F(v), g(x) and e(t) are continuous functions;n) Suppose that m 5 0 5 M, and that there exists a positive number V,such that when … 相似文献
76.
Daxiong Piao 《中国科学A辑(英文版)》2001,44(9):1156-1161
In this paper, we investigate the existence and uniqueness of new almost periodic type solutions, so-called pseudo almost
periodic solutions for the systems of differential equations with piecewise constant argument by means of introducing the
notion of pseudo almost periodic vector sequences 相似文献
77.
78.
本文主要研究了六维近凯勒流形的典范丛和Kodaira维数.证明了六维严格近凯勒流形的典范丛是拟全纯平凡的,从而其Kodaira维数为0.特别地,证明了三维复射影空间CP^3具有Kodaira维数不为-∞的近复结构.对于齐性的六维严格近凯勒流形,具体构造了它们典范丛的整体生成元.证明了齐性近凯勒流形F^3和CP^3的Hodge数h^1,0,h^2,0,h^2,3,h^1,3均为零. 相似文献
79.
Much research has been devoted to two problems, Yi yuancai fang (From a circular timber [find] a square) and Yi fangcai yuan (From a square timber [find] a circle), both of which appear in the Suanshu shu, an early Han dynasty mathematical work written on bamboo slips, excavated from tomb 247 at Zhangjiashan in Hubei Province, China. In this article, the geometric relations between circles and squares and the methods for determining their mutual relations in these two problems are interpreted in a different way, and an alternative approach is offered for reconciling these two problems. 相似文献
80.
YongSeung Cho 《中国科学 数学(英文版)》2014,57(9):1835-1840
The complex surface X obtained by 8 points blown up on CP2 and Barlow’s surface Y are homeomorphic,but not diffeomorphic.Using the Gromov-Witten invariant Ruan showed that the stabilized manifolds X×S2and Y×S2are not deformation equivalent.In this note,we show that the stabilized manifolds X×S1and Y×S1are diffeomorphic and non-deformation equivalent in cosymplectic sense. 相似文献