Results 11 to 20 of about 17,909,648 (352)
On Positivity Sets for Helmholtz Solutions
Vietnam Journal of Mathematics, 2023 AbstractWe address the question of finding global solutions of the Helmholtz equation that are positive in a given set. This question arises in inverse scattering for penetrable obstacles. In particular, we show that there are solutions that are positive on the boundary of a bounded Lipschitz domain.
Pu-Zhao Kow +2 more
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Positive Solutions of Difference Equations [PDF]
Proceedings of the American Mathematical Society, 1990 Necessary and sufficient condition for existence of positive solutions of the difference equation \((E)\quad (-1)^{m-1}\Delta^ mA_ n+\sum^{\infty}_{k=0}p_ kA_{n-\ell_ k}=0\) is established, where m is a positive integer, \((p_ k)_{k\geq 0}\) is a sequence of positive real numbers, \((\ell_ k)_{k\geq 0}\) is a sequence of integers with \(0\leq \ell_ ...
Philos, C. G., Sficas, Y. G.
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Positive Solutions of Positive Linear Equations [PDF]
Proceedings of the American Mathematical Society, 1972 Let B B be a real vector lattice and a Banach space under a semimonotonic norm. Suppose T T is a linear operator on B B which is positive and eventually compact, y y is a positive vector, and λ \lambda is a positive real. It is shown that (
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Algebraic Systems with Positive Coefficients and Positive Solutions
Mathematics, 2022 The paper is devoted to the existence, uniqueness and nonuniqueness of positive solutions to nonlinear algebraic systems of equations with positive coefficients. Such systems appear in large numbers of applications, such as steady-state equations in continuous and discrete dynamical models, Dirichlet problems, difference equations, boundary value ...
Ana Maria Acu +2 more
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Advances in Differential Equations, 2019 In this article, we consider a study of a general class of nonlinear singular fractional DEs with p-Laplacian for the existence and uniqueness (EU) of a positive solution and the Hyers–Ulam (HU) stability. To proceed, we use classical fixed point theorem
H. Khan +4 more
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Positive practices : solution-focused and narrative therapeutic techniques with children with sexually harmful behaviours [PDF]
, 2006 This article explores the use of solution-focused and Narrative Therapeutic approaches with a boy who had sexually harmful behaviours. The paper will highlight the practical challenges of working with someone who is 'problem-saturated' through ...
Berg I. K. +25 more
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Mathematical Modelling and Analysis, 2018 In this paper, we focus on the iterative scheme and error estimation of positive solutions for a class of p-Laplacian fractional order differential equation subject to Riemann-Stieltjes integral boundary condition.
Xinguang Zhang +4 more
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Existence of positive solution to Kirchhoff-Schrödinger-Poisson system with strong singular term
Journal of Mathematics and Physics, 2019 In this paper, we consider the existence of positive solution to the Kirchhoff-Schrodinger-Poisson system with strong singularity. By using the variational method, the necessary and sufficient condition for the existence of a solution is obtained.
Qi S. Zhang
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Journal of Taibah University for Science, 2019 In this paper, we will study solution existence and its stability for hybrid fractional DE with fractional integral, fractional differential derivative and Φp-operator in Caputo sense.
W. Al-Sadi +2 more
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Nonlinear Analysis, 2018 In this article, we study a class of nonlinear fractional differential equations with mixed-type boundary conditions. The fractional derivatives are involved in the nonlinear term and the boundary conditions. By using the properties of the Green function,
Fang Wang +3 more
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