Results 81 to 90 of about 292 (185)

Concave Soft Sets, Critical Soft Points, and Union-Soft Ideals of Ordered Semigroups

The Scientific World Journal, 2014
The notions of union-soft semigroups, union-soft l-ideals, and union-soft r-ideals are introduced, and related properties are investigated. Characterizations of a union-soft semigroup, a union-soft l-ideal, and a union-soft r-ideal are provided.
Young Bae Jun, Seok Zun Song, G. Muhiuddin   +2 more
doaj   +1 more source

Monotone iterative technique for nonlocal fractional differential equations with finite delay in Banach space

Electronic Journal of Qualitative Theory of Differential Equations, 2015
In this paper, we extend a monotone iterative technique for nonlocal fractional differential equations with finite delay in an ordered Banach space. By using the monotone iterative technique, theory of fractional calculus, semigroup theory and measure of
Kamal Jeet, Dhirendra Bahuguna
doaj   +1 more source

On Weakly Commutative Ordered Semigroups

Semigroup Forum, 1998
A partially ordered semigroup \((S, \cdot, \leq)\) is ``weakly commutative'' if for all \(a,b \in S\) there exist \(x\in S\) and a nonnegative integer \(n\) such that \((ab)^n \leq bxa\). It is ``archimedean'' if for all \(a,b\in S\) there exist \(x,y\in S\) and \(m\) such that \(a^m\leq xby\). It was shown by \textit{N.
Kehayopulu, N, Tsingelis, M
openaire   +2 more sources

Weakly Semiprime Segments in Ordered Semigroups

Mathematics, 2019
Let P 2 ⊂ P 1 be a pair of weakly semiprime ideals of an ordered semigroup ( S , · , ≤ ) . Then, the pair P 2 ⊂ P 1 is called a weakly semiprime segment of S if ⋂ n ∈ N I n ⊆ P 2
Panuwat Luangchaisri, Thawhat Changphas
doaj   +1 more source

A natural partial order for semigroups [PDF]

Proceedings of the American Mathematical Society, 1986
A partial order on a semigroup ( S , ⋅
openaire   +1 more source

On Epiorthodox Semigroups

International Journal of Mathematics and Mathematical Sciences, 2011
It has been well known that the band of idempotents of a naturally ordered orthodox semigroup satisfying the “strong Dubreil-Jacotin condition” forms a normal band.
Shouxu Du, Xinzhai Xu, K. P. Shum
doaj   +1 more source

On Intra-regular Ordered Semigroups

Semigroup Forum, 1998
An ordered semigroup \(S\) is intra-regular if and only if it is a semilattice of simple semigroups, equivalently, if \(S\) is a union of simple subsemigroups of \(S\) [\textit{N. Kehayopulu}, Semigroup Forum 46, 271-278 (1993; Zbl 0776.06013)]. A \(poe\)-semigroup \(S\) is a semilattice of simple semigroups if and only if it is a semilattice of simple
Kehayopulu, N, Tsingelis, M
openaire   +3 more sources

Positive Solutions for the Initial Value Problems of Fractional Evolution Equation

Journal of Function Spaces and Applications, 2013
This paper discusses the existence of positive solutions for the initial value problem of fractional evolution equation with noncompact semigroup , ; in a Banach space , where denotes the Caputo fractional derivative of order , is a closed linear ...
Yue Liang, Yu Ma, Xiaoyan Gao
doaj   +1 more source

Semigroup models for biochemical reaction networks. [PDF]

J Math Biol, 2023
Loutchko D.
europepmc   +1 more source

On intra-regular ordered semigroups

Semigroup Forum, 1993
The author continues her studies of partially ordered semigroups \(S\) which are intraregular, that is, for every \(a\in S\) there are \(x,y\in S\) such that \(a\leq xa^ 2 y\) [see the author, Semigroup Forum 44, 341-346 (1992; Zbl 0756.06008)]. It is shown (similar to the purely semigroup theoretical case) that a p.o.
openaire   +3 more sources