Algebra and Discrete Mathematics, 2007, № 1
http://dspace.nbuv.gov.ua:80/handle/123456789/150346
2026-04-22T14:32:27ZOn classification of CM modules over hypersurface singularities
http://dspace.nbuv.gov.ua:80/handle/123456789/157398
On classification of CM modules over hypersurface singularities
Bondarenko, V.V.
This article is devoted to a special case of classification problem for Cohen-Macaulay modules over hypersurface
singularities.
2007-01-01T00:00:00ZOn H-closed topological semigroups and semilattices
http://dspace.nbuv.gov.ua:80/handle/123456789/157357
On H-closed topological semigroups and semilattices
Chuchman, I.; Gutik, O.
In this paper, we show that if S is an H-closed
topological semigroup and e is an idempotent of S, then eSe is
an H-closed topological semigroup. We give sufficient conditions
on a linearly ordered topological semilattice to be H-closed. Also
we prove that any H-closed locally compact topological semilattice
and any H-closed topological weakly U-semilattice contain minimal idempotents. An example of a countably compact topological
semilattice whose topological space is H-closed is constructed.
2007-01-01T00:00:00ZOn Frobenius full matrix algebras with structure systems
http://dspace.nbuv.gov.ua:80/handle/123456789/157356
On Frobenius full matrix algebras with structure systems
Fujita, H.; Sakai, Y.; Simson, D.
Let n ≥ 2 be an integer. In [5] and [6], an n × n
A-full matrix algebra over a field K is defined to be the set Mn(K)
of all square n × n matrices with coefficients in K equipped with a
multiplication defined by a structure system A, that is, an n-tuple
of n × n matrices with certain properties. In [5] and [6], mainly
A-full matrix algebras having (0, 1)-structure systems are studied,
that is, the structure systems A such that all entries are 0 or 1.
In the present paper we study A-full matrix algebras having non
(0, 1)-structure systems. In particular, we study the Frobenius Afull matrix algebras. Several infinite families of such algebras with
nice properties are constructed in Section 4.
2007-01-01T00:00:00ZOn division rings with general involution
http://dspace.nbuv.gov.ua:80/handle/123456789/157349
On division rings with general involution
Idris, I.M.
In this work we consider division rings with general involution. Properties of such division rings are investigated.
General valuation of such division rings is introduced. We extend
to this general notion some result on the extension of valuations.
2007-01-01T00:00:00Z