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An improved oscillation theorem for nonlinear differential equations of advanced type

Nurten Kiliç, Özkan Öcalan, Mustafa Kemal Yildiz (2024)

Archivum Mathematicum

This paper deals with the oscillatory solutions of the first order nonlinear advanced differential equation. The aim of the present paper is to obtain an oscillation condition for this equation. This result is new and improves and correlates many of the well-known oscillation criteria that were in the literature. Finally, an example is given to illustrate the main result.

An improvement of the non-existence region for limit cycles of the Bogdanov-Takens system

Makoto Hayashi (2020)

Archivum Mathematicum

In this paper, an improvement of the global region for the non-existence of limit cycles of the Bogdanov-Takens system, which is well-known in the Bifurcation Theory, is given by two ideas. The first is to apply the existence of the algebraic invariant curve of the system to the Bendixson-Dulac criterion, and the second is to consider a necessary condition in order that a closed orbit of the system includes two equilibrium points. In virtue of these methods, it shall be shown that our previous result...

An integral condition of oscillation for equation y ' ' ' + p ( t ) y ' + q ( t ) y = 0 with nonnegative coefficients

Anton Škerlík (1995)

Archivum Mathematicum

Our aim in this paper is to obtain a new oscillation criterion for equation y ' ' ' + p ( t ) y ' + q ( t ) y = 0 with a nonnegative coefficients which extends and improves some oscillation criteria for this equation. In the special case of equation (*), namely, for equation y ' ' ' + q ( t ) y = 0 , our results solve the open question of C h a n t u r i y a .

An interplay between the weak form of Peano's theorem and structural aspects of Banach spaces

C. S. Barroso, M. A. M. Marrocos, M. P. Rebouças (2013)

Studia Mathematica

We establish some results that concern the Cauchy-Peano problem in Banach spaces. We first prove that a Banach space contains a nontrivial separable quotient iff its dual admits a weak*-transfinite Schauder frame. We then use this to recover some previous results on quotient spaces. In particular, by applying a recent result of Hájek-Johanis, we find a new perspective for proving the failure of the weak form of Peano's theorem in general Banach spaces. Next, we study a kind of algebraic genericity...

An Intracellular Delay-Differential Equation Model of the HIV Infection and Immune Control

T. Dumrongpokaphan, Y. Lenbury, R. Ouncharoen, Y. Xu (2010)

Mathematical Modelling of Natural Phenomena

Previous work has shown that intracellular delay needs to be taken into account to accurately determine the half-life of free virus from drug perturbation experiments [1]. The delay also effects the estimated value for the infected T-cell loss rate when we assume that the drug is not completely effective [19]. Models of virus infection that include intracellular delay are more accurate representations of the biological data.
We analyze a non-linear model of the human immunodeficiency virus (HIV)...

An Invariance Problem for Control Systems with Deterministic Uncertainty

Lech Górniewicz, Paolo Nistri (1996)

Banach Center Publications

This paper deals with a class of nonlinear control systems in R n in presence of deterministic uncertainty. The uncertainty is modelled by a multivalued map F with nonempty, closed, convex values. Given a nonempty closed set K R n from a suitable class, which includes the convex sets, we solve the problem of finding a state feedback ū(t,x) in such a way that K is invariant under any system dynamics f. As a system dynamics we consider any continuous selection of the uncertain controlled dynamics F.

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