Results 11 to 20 of about 1,790,928 (250)
The method of upper, lower solutions and hyperbolic partial differential equations
Journal of Mathematical Analysis and Applications, 1985 The authors extend the method of sub- and super-solutions to some initial value problems for certain nonlinear hyperbolic equations. They prove existence theorems and obtain minimal solutions. \{Reviewer's remark: It seems to the reviewer that their requirements on sub- and supersolutions are very restrictive.\}
Lakshmikantham, V, Pandit, S.G
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A theorem on upper–lower solutions for nonlinear elliptic systems and its applications
Journal of Mathematical Analysis and Applications, 2008 In this article the authors extend the classical result of an upper-lower solution technique to nonlinear non-homogeneous elliptic systems without the assumption of quasi-monotonicity under nonlinear boundary conditions. The method employed is Schauder's fixed point theorem.
Li, Lige, Abudiab, Mufid, Ahn, Inkyung
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Almost Periodic Solutions of First-Order Ordinary Differential Equations
Mathematics, 2018 Approaches to estimate the number of almost periodic solutions of ordinary differential equations are considered. Conditions that allow determination for both upper and lower bounds for these solutions are found.
Seifedine Kadry +3 more
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On the stability of solutions of the Lichnerowicz-York equation [PDF]
, 2013 We study the stability of solution branches for the Lichnerowicz-York equation at moment of time symmetry with constant unscaled energy density. We prove that the weak-field lower branch of solutions is stable whilst the upper branch of strong-field ...
Walsh, Darragh M
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Causal difference equations with upper and lower solutions in the reverse order
Advances in Difference Equations, 2019 This paper is devoted to studying the existence conditions for difference equations involving causal operators in the presence of upper and lower solutions in the reverse order. To this end, we prove some new comparison theorems and develop the upper and
Wen-Li Wang, Jing-Feng Tian
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Discrete and Continuous Dynamical Systems - B, 2019 We prove existence and uniqueness of weak and classical solutions to certain semi-linear parabolic systems with Robin boundary conditions using the coupled upper-lower solution approach. Our interest lies in cross-dependencies on the gradient parts of the reaction term, which prevents the straight-forward application of standard theorems.
Anne Mund +2 more
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The upper–lower solution method for the coupled system of first order nonlinear PDEs
Journal of Mathematical Analysis and Applications, 2013 Abstract This paper is concerned with a coupled system of first order nonlinear partial differential equations. This system is, but not limited in, the extended case of the general blood–tissue exchange model (BTEX). We use the solutions of a coupled system of first order ordinary differential equations to construct a pair of ordered lower and upper ...
Guo-Chin Jau, Yu-Hsien Chang
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On positive solutions of the Dirichlet problem involving the extrinsic mean curvature operator
Electronic Journal of Qualitative Theory of Differential Equations, 2016 In this paper, we are concerned with necessary conditions for the existence of positive solutions of the Dirichlet problem for the prescribed mean curvature equation in Minkowski space \begin{equation*} \begin{aligned} -\text{div}\left(\frac {\nabla u}{\
Ruyun Ma, Tianlan Chen, Hongliang Gao
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Semilinear elliptic equations in thin regions with terms concentrating on oscillatory boundaries [PDF]
, 2018 In this work we study the behavior of a family of solutions of a semilinear elliptic equation, with homogeneous Neumann boundary condition, posed in a two-dimensional oscillating thin region with reaction terms concentrated in a neighborhood of the ...
Arrieta, José M. +2 more
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Traveling wave solutions for an integrodifference equation of higher order
AIMS Mathematics, 2022 This article is concerned with the minimal wave speed of traveling wave solutions for an integrodifference equation of higher order. Besides the operator may be nonmonotone, the kernel functions may be not Lebesgue measurable and integrable such that the
Fuzhen Wu
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