带有限性条件Abel群的自同态环和自同构群

给出了带极大或极小条件的Abel群A的自同构群以及自同态环的相伴Lie环是可解或幂零的充要条件.同时也给出了群A=Q_(π1)⊕Q_(π2)⊕…⊕Q_(πr)的自同构群是可解或幂零的充要条件,以及群A的自同态环的相伴Lie环是可解或幂零的充要条件.     

On an Isomorphism Problem for Endomorphism Near-Rings

Suppose and are endomorphism near-rings generated by
groups of automorphisms containing the inner automorphisms of two respective finite perfect groups and . In this note we show that if and are isomorphic, then and are isomorphic.

     

On QB Endomorphism Rings

We study, in this article, QB endomorphism rings of quasi-projective modules by means of completions of diagrams. The dual problems for quasi-injective modules are also investigated.     

关于正则模的自同态环

本文研究正则模Ｐ的自同态环Ｓ，主要给出使Ｓ的稳定秩为１的Ｐ的几个充分条件．     

关于自同构群方程|Aut(G)|=P2Q2

本文给出满足｜Aut(G)｜=p2q2的有限群G的完全分类,p和q是不同的素数.     

Conditions for a function to be a centralizer on an H*-algebra

Research partially supported by the Hungarian National Research Science Foundation, Operating Grant Number OTKA 1652.     

The Jacobson Radical of an Endomorphism Ring for an Abelian Group

The Jacobson radical of an endomorphism ring is computed for a completely decomposable torsion-free Abelian group and for a mixed Abelian group in one class of mixed groups. For the latter case, we also look into the question when a factor ring w.r.t. the radical is regular in the sense of Nuemann.     

Sufficient Conditions for a Digraph to be Supereulerian

A (di)graph is supereulerian if it contains a spanning eulerian sub(di)graph. This property is a relaxation of hamiltonicity. Inspired by this analogy with hamiltonian cycles and by similar results in supereulerian graph theory, we analyze a number of sufficient Ore type conditions for a digraph to be supereulerian. Furthermore, we study the following conjecture due to Thomassé and the first author: if the arc‐connectivity of a digraph is not smaller than its independence number, then the digraph is supereulerian. As a support for this conjecture we prove it for digraphs that are semicomplete multipartite or quasitransitive and verify the analogous statement for undirected graphs.     

Conditions for variable-metric algorithms to be conjugate-gradient algorithms

Variable-metric algorithms have played an important role in unconstrained optimization theory. This paper presents a sufficiency condition on the sequence of metrics in a variable-metric algorithm that will make it a conjugate-gradient algorithm. The Huang class of algorithms (Ref. 1) and the class of self-scaling variable-metric algorithms by Oren (Ref. 2) all satisfy the condition. This paper also includes a discussion of the behavior of algorithms that meet the condition on nonquadratic functions.     

Conditions for Acts over Semilattices to be Cantor

Mathematical Notes - An algebra $$A$$ is said to be Cantor if a theorem similar to the Cantor– Bernstein– Schröder theorem holds for it; namely, if, for any algebra $$B$$ , the...     

Cauchy-Riemann Automorphism Groups that cannot be projectively realized

LetM ? ?ⁿ be a real-analytic, nonspherical hypersurface passing through the origin and having nondegenerate Levi form. Let Aut₀ M be the stability group of 0. Whenn = 12 an example is constructed for which Aut₀ M cannot be linearized.     

Conditions for separately subharmonic functions to be subharmonic

Letu be a function on ^m × ⁿ , wherem2 andn2, such thatu(x, .) is subharmonic on ⁿ for each fixedx in ^m andu(.,y) is subharmonic on ^m for each fixedy in ⁿ . We give a local integrability condition which ensures the subharmonicity ofu on ^m × ⁿ , and we show that this condition is close to being sharp. In particular, the local integrability of (log⁺ u ⁺) ^m+n–2+ is enough to secure the subharmonicity ofu if >0, but not if <0.     

Conditions for graphs to be path partition optimal

The path partition number of a graph is the minimum number of edges we have to add to turn it into a Hamiltonian graph, and the separable degree is the minimum number of edges we have to add to turn it into a 2-connected graph. A graph is called path partition optimal if its path partition number is equal to its separable degree. We study conditions that guarantee path partition optimality. We extend several known results on Hamiltonicity to path partition optimality, in particular results involving degree conditions and induced subgraph conditions.