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61.
Chen Qing 《淮北煤炭师范学院学报(自然科学版)》1990,(2)
本文对内射 C~*-代数作了进一步讨论,给出了内射 C~*-代数的子代数是内射的一个充分条件与内射 C~*-代数的某些结果。 相似文献
62.
On the Construction of <Emphasis Type="Italic">p</Emphasis>-Harmonic Morphisms and Conformal Actions
Xiao Huan MO Li Bing HUANG Yuan Zheng ZHANG 《数学学报(英文版)》2007,23(8):1475-1484
We produce p-harmonic morphisms by conformal foliations and Clifford systems. First, we give a useful criterion for a foliation on an m-dimensional Riemannian manifold locally generated by conformal fields to produce p-harmonic morphisms. By using this criterion we manufacture conformal foliations, with codimension not equal to p, which are locally the fibres of p-harmonic morphisms. Then we give a new approach for the construction of p-harmonic morphisms from R^m/{0} to R^n. By the well-known representation of Clifford algebras, we find an abundance of the new 2/3 (m + 1)-harmonic morphism Ф: R^m/{0} → R^n where m = 2κδ(n - 1). 相似文献
63.
Dual maps have been introduced as a generalization to higher dimensions of word substitutions and free group morphisms. In this paper, we study the action of these dual maps on particular discrete planes and surfaces, namely stepped planes and stepped surfaces. We show that dual maps can be seen as discretizations of toral automorphisms. We then provide a connection between stepped planes and the Brun multi-dimensional continued fraction algorithm, based on a desubstitution process defined on local geometric configurations of stepped planes. By extending this connection to stepped surfaces, we obtain an effective characterization of stepped planes (more exactly, stepped quasi-planes) among stepped surfaces. 相似文献
64.
拉回正合范畴是Abelian范畴的真正推广,是界在正合范畴与Abelian范畴之间的一类范畴.本文利用拉回-推出,引进拉回正合范畴的小子对象概念,并给出小子对象相关的性质以及等价条件. 相似文献
65.
Some recent results of Ayache on going-down domains and extensions of domains that either are residually algebraic or have DCC on intermediate rings are generalized to the context of extensions of commutative rings. Given a finite maximal chain 𝒞 of R-subalgebras of a weak Baer ring T, it is shown how a “min morphism” hypothesis can be used to transfer the “going-down ring” property from R to each member of 𝒞. The integral minimal ring extensions which are min morphisms are classified. The ring extensions satisfying FCP (i.e., for which each chain of intermediate rings is finite) are characterized as the strongly affine extensions with DCC on intermediate rings. In the relatively integrally closed case, such extensions R ? T induce open immersions Spec(S) → Spec(R) for each R-subalgebra S of T. 相似文献
66.
Igor Burban 《代数通讯》2013,41(8):2983-2988
In this article, we describe the action of the Frobenius morphism on the indecomposable vector bundles on cycles of projective lines. This gives an answer to a question of Paul Monsky, which appeared in his study of the Hilbert–Kunz theory for plane cubic curves. 相似文献
67.
Claudia Chaio 《代数通讯》2013,41(12):4419-4424
We characterize the finiteness of the representation type of an artin algebra in terms of the behavior of the projective covers and the injective envelopes of the simple modules with respect to the infinite radical of the module category. In case the algebra is representation-finite, we show that the nilpotency of the radical of the module category is the maximal depth of the composites of these maps, which is independent from the maximal length of the indecomposable modules. 相似文献
68.
设是一个范畴,S是的一个局部类.构造的态射范畴的一个左局部化范畴C[■-1],并给出一定条件下,由不同对象确定的态射范畴及其左局部化之间的关系. 相似文献
69.
讨论了分块态射的Moore-Penrose逆,用不同与文[1]的方法给出了分块态射f=(u v)的Moore-Penrose逆表达式.这个表达式与Petr Peska(2000)给出的等价. 相似文献
70.