Results 11 to 20 of about 345,519 (275)
On the Number of Nonnegative Solutions to the Inequality a1 +....ar < n [PDF]
, 2010 In this paper, we present a simple and fast method for counting the number of nonnegative integer solutions to the equality a1x1+a2x2+: : :+arxr = n where a1; a2; :::; ar and n are positive integers.
Farzaneh , A. +3 more
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Upper and Lower Solutions and Multiplicity Results [PDF]
Journal of Mathematical Analysis and Applications, 2000 Using the topological degree theory, the author obtains some multiplicity results for the second-order differential equation \(x''=f(t,x,x')\), with both linear (periodic and Neumann) and nonlinear boundary conditions. Here, \(f:[a,b]\times \mathbb{R}^2 \to \mathbb{R}\) is continuous and satisfies certain growth conditions.
Rachůnková, Irena
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Upper–lower solutions for nonlinear parabolic systems and their applications [PDF]
Journal of Mathematical Analysis and Applications, 2011 A method of upper and lower-solutions for nonlinear time-dependent reaction-diffusion systems of the type \[ \begin{cases} {\partial \over {\partial t}} u_i(x,t) - d_i \Delta u_i(x,t)= f_i(u_1,\dots,u_m, x) \quad \text{ for } x\in \Omega \subset \mathbb R^m \\ \alpha_i u_i(x,t) + \beta_i {\partial \over \partial n} u_i(x,t) = \psi_i(u_1,\dots,u_{i-1 ...
Abudiab, Mufid, Ahn, Inkyung, Li, Lige
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Existence of solutions and convergence results for dynamic initial value problems using lower and upper solutions [PDF]
Electronic Journal of Differential Equations, 2009 In this article, we study the existence of solutions to first order non-linear initial value problems within the field of "dynamic equations on time scales". We employ the method of upper and lower solutions and Schauder's fixed point theorem.
Atiya H. Zaidi
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Upper and lower solutions satisfying the inverse inequality [PDF]
Annales Polonici Mathematici, 1997 Summary: We consider multipoint and two-point BVPs for second order ordinary differential equations with a Carathéodory right hand side. We prove the existence of solutions provided there exist upper and lower solutions of the BVP and the upper solution is less than the lower one.
Rachůnková, Irena
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Existence of solutions for Kirchhoff-type problems via the method of lower and upper solutions [PDF]
Electronic Journal of Differential Equations, 2019 This article considers elliptic problems of Kirchhoff-type. We give some new definitions of lower and upper solutions for the problem and establish the method of lower and upper solutions when the upper and lower solutions are well ordered, i.e., the ...
Baoqiang Yan +2 more
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International Journal of Differential Equations, 2011 We consider a kind of Sturm-Liouville boundary value problems. Using variational techniques combined with the methods of upper-lower solutions, the existence of at least one positive solution is established.
Li Zhang, Xiankai Huang, Weigao Ge
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3D ultimate limit state analysis using discontinuity layout optimization [PDF]
, 2012 The recently developed discontinuity layout optimization (DLO) procedure uses limit analysis theory to directly obtain upper bounds on plane strain collapse loads of bodies and has successfully been applied to geotechnical problems.
Hawksbee, Samuel John
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Method of upper and lower solutions for fractional differential equations [PDF]
Electronic Journal of Differential Equations, 2012 In this paper, we show the existence and uniqueness of solutions for the boundary-value problems of fractional differential equations, using the upper and lower solutions method and monotone iterative algorithm.
Legang Lin, Xiping Liu, Haiqin Fang
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Lower semicontinuity of attractors for non-autonomous dynamical systems [PDF]
, 2009 This paper is concerned with the lower semicontinuity of attractors for semilinear non-autonomous differential equations in Banach spaces. We require the unperturbed attractor to be given as the union of unstable manifolds of time-dependent hyperbolic
Langa, José A. +3 more
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