(Weakly) n-nil cleanness of the ring Zm Khashan,Hani A; Handam,Ali H
Communications Series A1 Mathematics & Statistics,
2/2018, Letnik:
67, Številka:
2
Journal Article
Recenzirano
Let R be an associative ring with identity. For a positive integer n≥2, an element a∈R is called n-potent if aⁿ=a . We define R to be (weakly) n-nil clean if every element in R can be written as a ...sum (a sum or a difference) of a nilpotent and an n-potent element in R. This concept is actually a generalization of weakly nil clean rings introduced by Danchev and McGovern, 6. In this paper, we completely determine all n,m∈ℕ such that the ring of integers modulo m, ℤm is (weakly) n-nil clean.
In this paper, we defined (F, h, a, u) -( ) -contractions using pair of (F, h) upper class functions for a-admissible and u-subadmissible mappings.We proved some fixed point theorems for this type ...contractive mappings in b-metric spaces. Our results generalize a-admissible results in the literature.
This article presents optimal fractional control. This control is based on the property of the invariance of a fractional order differential equation. The problem formulation of the used control is ...expressed by diffusive representation. The fractional control problem is described in a minimization form, where the global optimum represents the diffusive realization of the controller. To determine the optimal fractional diffusive control, an adaptive partitioning algorithm is used. As an application, we have chosen the control of a DC motor with uncertain parameters.
Stancu type (p; q)-Szász-Mirakyan-Baskakov operators Acar,Tuncer; Mursaleen,Mohammad; Mohiuddine,S. A
Communications Faculty of Sciences University of Ankara series A1: mathematics and statistics,
1/2018, Letnik:
67, Številka:
1
Journal Article
Recenzirano
Odprti dostop
In the present paper, we introduce Stancu type generalization of (p, q)-Szasz-Mirakyan-Baskakov operators and investigate their approximation properties such as weighted approximation, rate of ...convergence and pointwise convergence.
Ebola virus is one of the most virulent pathogens for humans. We present a mathematical description of different Susceptible-Exposed-Infectious- Recovered (SEIR) models. By using mathematical ...modeling and analysis, the latest major outbreak of Ebola virus in West Africa is described. Our aim is to study and discuss the properties of SEIR models with respect to Ebola virus, the information they provide, and when the models make sense. We added to the basic SEIR model demographic effects in order to analyze the equilibria with vital dynamics. Numerical simulations confirm the theoretical analysis. The control of the propagation of the virus through vaccination is investigated and the case study of Liberia is discussed in detail.
Semi-invariant semi-Riemannian submersions Akyol,Mehmet Akif
Communications Faculty of Sciences University of Ankara series A1: mathematics and statistics,
1/2018, Letnik:
67, Številka:
1
Journal Article
Recenzirano
Odprti dostop
In this paper, we introduce semi-invariant semi-Riemannian submersions
from para-Kahler manifolds onto semi-Riemannian manifolds. We
give some examples, investigate the geometry of foliations that ...arise from
the definition of a semi-Riemannian submersion and check the harmonicity of
such submersions. We also find necessary and sufficient conditions for a semiinvariant
semi-Riemannian submersion to be totally geodesic. Moreover, we
obtain curvature relations between the base manifold and the total manifold.
Strongly _-clean properties and rings of functions Chen,Huanyin; Harmancı,Abdullah
Communications Faculty of Sciences University of Ankara series A1: mathematics and statistics,
1/2018, Letnik:
67, Številka:
1
Journal Article
Recenzirano
Odprti dostop
A *-ring R is called a strongly *-clean ring if every element of
R is the sum of a unit and a projection that commute with each other. In
this paper, we explore strong ^-cleanness of rings of ...continuous functions over
spectrum spaces. We prove that a *-ring R is strongly *-clean if and only if R
is an abelian exchange ring and C (X ) (C * (X )) is *-clean, if and only if R is
an abelian exchange ring and the classical ring of quotients q (C (X )) of C (X )
is *-clean, where X is a spectrum space of R.