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11.
J. Ignacio Extremiana Aldana L. Javier Herná ndez Paricio M. Teresa Rivas Rodrí guez 《Proceedings of the American Mathematical Society》1996,124(11):3545-3553
For each integer , we give a distinct closed model category structure to the category of pointed spaces such that the corresponding localized category is equivalent to the standard homotopy category of -connected CW-complexes. The structure of closed model category given by Quillen to is based on maps which induce isomorphisms on all homotopy group functors and for any choice of base point. For each , the closed model category structure given here takes as weak equivalences those maps that for the given base point induce isomorphisms on for .
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Michael P. Drazin 《代数通讯》2020,48(4):1423-1438
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Esmaeil Hosseini 《代数通讯》2019,47(9):3781-3788
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Nick Gurski 《Advances in Mathematics》2011,(5):4225
We prove a coherence theorem for braided monoidal bicategories and relate it to the coherence theorem for monoidal bicategories. We show how coherence for these structures can be interpreted topologically using up-to-homotopy operad actions and the algebraic classification of surface braids. 相似文献
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Guang Gui Ding 《数学学报(英文版)》2015,31(12):1872-1878
In this article, we use some analytic and geometric characters of the smooth points in a sphere to study the isometric extension problem in the separable or reflexive real Banach spaces. We obtain that under some condition the answer to this problem is affirmative. 相似文献
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In this research, the experimental tests of quasi-static three-point bending and three-point bending fatigue were carried out for a ±25° biaxial braided carbon fibre reinforced polymer (CFRP) manufactured using vacuum assisted resin transfer moulding (VARTM). A finite element (FE) model was also set up for quasi-static testing and the prediction results revealed that local fibre volume fraction (FVF) is a primary source affecting the mechanical properties of braided CFRP. The fatigue of the braided CFRP was defined as three different stages according to the flexural modulus results. The damage modes of the test specimens were observed via a digital microscope and scanning electron microscope (SEM) and the process-induced defects were summarised. With compiled results and observations, this study provides a better understanding of failure and fatigue behaviour of biaxial braided composites and their flexural properties which offers a good basis for any further research in fibre volume fractions, structure design and manufacturing for braided CFRP. 相似文献
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态射的广义Moore—Penrose逆 总被引:22,自引:4,他引:22
本文定义了态射的广义Moore-Penrose逆,给出了它存在的一些充要条件,确定了它的一些表达式,推广了关于态射的Moore-Penrose逆的相应结果。 相似文献