Results 1 to 10 of about 1,228,906 (333)
Positive solutions of advanced differential systems. [PDF]
ScientificWorldJournal, 2013 We study asymptotic behavior of solutions of general advanced differential systems , where F : Ω → ℝn is a continuous quasi‐bounded functional which satisfies a local Lipschitz condition with respect to the second argument and Ω is a subset in , , yt∈, and yt(θ) = y(t + θ), θ ∈ [0, r]. A monotone iterative method is proposed to prove the existence of a
Diblík J, Kúdelčíková M.
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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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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 (
Paul D. Nelson
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On Positive Solutions of the Heat Equation [PDF]
Nagoya Mathematical Journal, 1967 Consider the positive and twice continuously differentiable solutions u of the heat equationin an open t-strip Ω = Rn×(0,T) for some T>0, where Rn is the n-dimensional Euclidean space.In this note, we prove a theorem of Fatou type on u and, as its application, the uniqueness theorem for the Cauchy problem of ( 1 ).
Masasumi Kato
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On the positive solutions of the Matukuma equation [PDF]
Duke Mathematical Journal, 1993 where p > 1 and u > 0 is the gravitational potential with f R3 (uP/4n(1 + Ix12» dx representing the total mass. His aim was to improve a model given earlier in 1915 by A. S. Eddington. (See [NY1,2] for a more detailed history of these two models.) Since the Matukuma equation (1.1)is rotationally invariant, the structure of positive radial solutions u(r,
Yi Li
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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 Proceedings of the American Mathematical ...
Philos, C. G., Sficas, Y. G.
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On the positivity of solutions of systems of stochastic PDEs [PDF]
ZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik, 2012 AbstractWe study the positivity of solutions of a class of semi‐linear parabolic systems of stochastic partial differential equations by considering random approximations. For the family of random approximations we derive explicit necessary and sufficient conditions such that the solutions preserve positivity.
Messoud Efendiev +3 more
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Solutions and positive solutions for superlinear Robin problems [PDF]
Journal of Mathematical Physics, 2019 We consider nonlinear, nonhomogeneous Robin problems with a (p − 1)-superlinear reaction term, which need not satisfy the Ambrosetti-Rabinowitz condition. We look for positive solutions and prove existence and multiplicity theorems. For the particular case of the p-Laplacian, we prove existence results under a different geometry near the origin.
N. S. Papageorgiou, C. Vetro, F. Vetro
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Existence of a positive solution for a singular system [PDF]
Proceedings of the Royal Society of Edinburgh: Section A Mathematics, 2010 We show the existence and non-existence of positive solutions to a system of singular elliptic equations with the Dirichlet boundary condition.
Da Silva Montenegro, Marcelo +1 more
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