Intervals of certain classes of Z-matrices
Journal Title: Discussiones Mathematicae - General Algebra and Applications - Year 2014, Vol 34, Issue 1
Abstract
Let A and B be M-matrices satisfying A ≤ B and J = [A, B] be the set of all matrices C such that A ≤ C ≤ B, where the order is component wise. It is rather well known that if A is an M-matrix and B is an invertible Mmatrix and A ≤ B, then aA + bB is an invertible M-matrix for all a, b > 0. In this article, we present an elementary proof of a stronger version of this result and study corresponding results for certain other classes as well. Keywords: interval matrix, M-matrix, N-matrix, N0-matrix, nonnegativity. 2010 Mathematics Subject Classification: 15A48, 15A45.
Authors and Affiliations
M. Kannan, K. Sivakumar
LEFT ZEROID AND RIGHT ZEROID ELEMENTS OF Γ-SEMIRINGS
In this paper we introduce the notion of a left zeroid and a right zeroid of Γ-semirings. We prove that, a left zeroid of a simple Γ-semiring M is regular if and only if M is a regular Γ-semiring.
Filters of lattices with respect to a congruence
Some properties of filters on a lattice L are studied with respect to a congruence on L. The notion of a θ-filter of L is introduced and these filters are then characterized in terms of classes of θ. For distributive L,...
Characterizations of ordered Γ-Abel-Grassmann's groupoids
In this paper, we introduced the concept of ordered Γ-AG-groupoids, Γ- ideals and some classes in ordered Γ-AG-groupoids. We have shown that every Γ-ideal in an ordered Γ-AG∗∗-groupoid S is Γ-prime if and only if it is Γ...
A Note on Additive Groups of Some Specific Torsion-Free Rings of Rank Three and Mixed Associative Rings
It is studied how rank two pure subgroups of a torsion-free Abelian group of rank three influences its structure and type set. In particular, the criterion for such a subgroup B to be a direct summand of a torsion-free A...
Idempotent Elements of Weak Projection Generalized Hypersubstitutions
A generalized hypersubstitution of type τ = (ni)i∈I is a mapping σ which maps every operation symbol fi to the term σ(fi) and may not preserve arity. It is the main tool to study strong hyperidentities that are used to c...