On the existence of positive solutions of a state-dependent neutral functional differential equation with two state-delay functions

OMA-Vol. 4 (2020), Issue 2, pp. 132 – 141 Open Access Full-Text PDF
El-Sayed, A. M. A, Hamdallah, E. M. A, Ebead, H. R
Abstract: In this paper, we study the existence of positive solutions for an initial value problem of a state-dependent neutral functional differential equation with two state-delay functions. The continuous dependence of the unique solution will be proved. Some especial cases and examples will be given.
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Degree affinity number of certain \(2\)-regular graphs

ODAM-Vol. 3 (2020), Issue 3, pp. 77 – 84 Open Access Full-Text PDF
Johan Kok
Abstract: This paper furthers the study on a new graph parameter called the degree affinity number. The degree affinity number of a graph \(G\) is obtained by iteratively constructing graphs, \(G_1,G_2,\dots,G_k\) of increased size by adding a maximal number of edges between distinct pairs of distinct vertices of equal degree. Preliminary results for certain \(2\)-regular graphs are presented.
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Approximate solution of nonlinear ordinary differential equation using ZZ decomposition method

OMS-Vol. 4 (2020), Issue 1, pp. 448 – 455 Open Access Full-Text PDF
Mulugeta Andualem, Atinafu Asfaw
Abstract: Nonlinear initial value problems are somewhat difficult to solve analytically as well as numerically related to linear initial value problems as their variety of natures. Because of this, so many scientists still searching for new methods to solve such nonlinear initial value problems. However there are many methods to solve it. In this article we have discussed about the approximate solution of nonlinear first order ordinary differential equation using ZZ decomposition method. This method is a combination of the natural transform method and Adomian decomposition method.
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Weak implicative UP-filters of UP-algebras

OMS-Vol. 4 (2020), Issue 1, pp. 442 – 447 Open Access Full-Text PDF
Daniel A. Romano, Young Bae Jun
Abstract: The concept of weak implicative UP-filters in UP-algebras is introduced and analyzed. Some characterizations of weak implicative UP-filters are derived with the using of some other filter types in such algebras.
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Exponential decay of solutions with \(L^{p}\) -norm for a class to semilinear wave equation with damping and source terms

OMA-Vol. 4 (2020), Issue 2, pp. 123 – 131 Open Access Full-Text PDF
Amar Ouaoua, Messaoud Maouni, Aya Khaldi
Abstract: In this paper, we consider an initial value problem related to a class of hyperbolic equation in a bounded domain is studied. We prove local existence and uniqueness of the solution by using the Faedo-Galerkin method and that the local solution is global in time. We also prove that the solutions with some conditions exponentially decay. The key tool in the proof is an idea of Haraux and Zuazua with is based on the construction of a suitable Lyapunov function.
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On sufficient conditions for a graph to be \(k\)-path-coverable, \(k\)-edge-hamiltonian, Hamilton-connected, traceable and \(k^{-}\)-independent

ODAM-Vol. 3 (2020), Issue 3, pp. 66 – 76 Open Access Full-Text PDF
Junjiang Li, Guifu Su, Huichao Shi, Fuguo Liu
Abstract: The inverse degree of a graph was defined as the sum of the inverses of the degrees of the vertices. In this paper, we focus on finding sufficient conditions in terms of the inverse degree for a graph to be \(k\)-path-coverable, \(k\)-edge-hamiltonian, Hamilton-connected and traceable, respectively. The results obtained are not dropped.
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Homomorphism of intuitionistic fuzzy multigroups

OMS-Vol. 4 (2020), Issue 1, pp. 430 – 441 Open Access Full-Text PDF
I. M. Adamu
Abstract: This paper introduces the concept of homomorphism in intuitionistic fuzzy multigroups context. It also investigates Some homomorphic properties of intuitionistic fuzzy multigroups. It is shown that the homomorphic image and homomorphic preimage of intuitionistic fuzzy multigroups are also intuitionistic fuzzy multigroups. Finally, it presents some homomorphic properties of normalizer of intuitionistic fuzzy multigroups.
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Stability of stochastic 2D Navier-Stokes equations with memory and Poisson jumps

OMS-Vol. 4 (2020), Issue 1, pp. 417 – 429 Open Access Full-Text PDF
Diem Dang Huan
Abstract: The objective of this paper is to study the stability of the weak solutions of stochastic 2D Navier-Stokes equations with memory and Poisson jumps. The asymptotic stability of the stochastic Navier-Stoke equation as a semilinear stochastic evolution equation in Hilbert spaces is obtained in both mean square and almost sure senses. Our results can extend and improve some existing ones.
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