Ara
Toplam kayıt 46, listelenen: 41-46
A Generalization of Projective Covers
(Academic Press Inc Elsevier Science, 2008)
Let M be a left module over a ring R and I an ideal of R. We call (P, f) a projective I-cover of M if f is an epimorphism from P to M, P is projective, Ker f subset of I P, and whenever P = Ker f + X, then there exists a ...
Finite-Dimensional Attractors For A General Class Of Nonautonomous Wave Equations
(Pergamon-Elsevier Science Ltd, 2000)
Our aim in this note is to construct attractors and exponential attractors for a general class of nonautonomous semilinear wave equations. Following the approach described in [1], we define a semigroup S(t) associated to ...
On Hollow-Lifting Modules
(Mathematical Soc Rep China, 2007)
Let R be any ring and let M be any right R-module. M is called hollow-lifting if every submodule N of M such that M/N is hollow has a coessential submodule that is a direct summand of M. We prove that every amply supplemented ...
On T-Noncosingular Modules
(Cambridge Univ Press, 2009)
In this paper we introduce T-noncosingular modules. Rings for which all right modules are T-noncosingular are shown to be precisely those for which every simple right module is injective. Moreover, for any ring R we show ...
Spatial Behavior Estimates For The Wave Equation Under Nonlinear Boundary Conditions
(Pergamon-Elsevier Science Ltd, 2001)
Our aim is to establish a spatial decay and growth estimates for solutions of the initial-boundary value problem for the linear wave equation with the damping term under nonlinear boundary conditions. (C) 2001 Elsevier ...
Restructuring E-Learning With Ontologies
(Ieee, 2007)
This paper examines the role of ontologies in the e-learning environments. A brief review of various ontologies is discussed in three areas: Learning design, learning content and learner profile. A new perspective for ...