Results 11 to 20 of about 524,417 (274)
Electronic Journal of Qualitative Theory of Differential Equations, 2019 In this paper, we are concerned with the existence of positive solutions of nonlinear periodic boundary value problems like \begin{equation*} \begin{split} &-u''+q(x)u=\lambda f(x,u),\qquad x\in(0,2\pi),\\ &u(0)=u(2\pi),\qquad u'(0)=u'(2\pi), \end{split}
Zhiqian He, Ruyun Ma, Man Xu
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Positive periodic solutions to impulsive delay differentialequations
TURKISH JOURNAL OF MATHEMATICS, 2017 Summary: In this paper we discuss the existence of positive periodic solutions for nonautonomous second order delay differential equations with singular nonlinearities in the presence of impulsive effects. Simple sufficient conditions are provided that enable us to obtain positive periodic solutions. Our approach is based on a variational method.
Daoudi-Merzagui, Naima, Dib, Fatima
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Positive Periodic Solutions for Nonlinear Difference Equations with Periodic Coefficients
Journal of Mathematical Analysis and Applications, 1999 The authors consider the following boundary value problem \[ -\Delta [p(n-1)\Delta y(n-1)]+q(n) y(n)=f(n,y(n)), \quad n=1,2,\dots,N, \] \[ y(0)=y(N),\qquad p(0)\Delta y(0)=p(N)\Delta y(N). \] Using a fixed point theorem in cones, existence of one as well as two solutions is established for the boundary value problem.
Atici, FM, Guseinov, GS
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, 2001 We consider a 6D space-time which is periodic in one of the extra dimensions and compact in the other. The periodic direction is defined by two 4-brane boundaries.
Kanti, Panagiota +2 more
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On periodic solutions of 2-periodic Lyness difference equations [PDF]
, 2012 We study the existence of periodic solutions of the non--autonomous periodic Lyness' recurrence u_{n+2}=(a_n+u_{n+1})/u_n, where {a_n} is a cycle with positive values a,b and with positive initial conditions.
GUY BASTIEN +4 more
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Positive periodic solutions in neutral nonlinear differential equations
Electronic Journal of Qualitative Theory of Differential Equations, 2007 We use Krasnoselskii's fixed point theorem to show that the nonlinear neutral differential equation with delay \begin{equation} \frac{d}{dt}[x(t) - ax(t-\tau)]= r(t)x(t)- f(t, x(t-\tau)) \end{equation} has a positive periodic solution.
Youssef Raffoul
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On a fourth order nonlinear Helmholtz equation [PDF]
, 2018 In this paper, we study the mixed dispersion fourth order nonlinear Helmholtz equation $\Delta^2 u -\beta \Delta u + \alpha u= \Gamma|u|^{p-2} u$ in $\mathbb R^N$ for positive, bounded and $\mathbb Z^N$-periodic functions $\Gamma$.
Abramowitz M. +11 more
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Positive periodic solutions for discrete time-delay hematopoiesis model with impulses
Open Mathematics, 2023 The present article is devoted to the positive periodic solution for impulsive discrete hematopoiesis model. This model is described by a first-order nonlinear difference equation with multiple delays and impulses.
Yan Yan
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Positive periodic solutions for nonlinear first-order delayed differential equations at resonance
Boundary Value Problems, 2018 This paper studies the existence of positive periodic solutions of the following delayed differential equation: u′+a(t)u=f(t,u(t−τ(t))), $$ u'+a(t)u=f\bigl(t,u\bigl(t-\tau (t)\bigr)\bigr), $$ where a,τ∈C(R,R) $a, \tau \in C(\mathbb{R},\mathbb{R})$ are ω ...
Ruipeng Chen, Xiaoya Li
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Existence of periodic orbits in nonlinear oscillators of Emden-Fowler form [PDF]
, 2015 The nonlinear pseudo-oscillator recently tackled by Gadella and Lara is mapped to an Emden-Fowler (EF) equation that is written as an autonomous two-dimensional ODE system for which we provide the phase-space analysis and the parametric solution. Through
Mancas, S. C., Rosu, H. C.
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