Results 1 to 10 of about 1,625 (133)

Two modifications of the Leggett-Williams fixed point theorem and their applications

Electronic Journal of Differential Equations, 2010
This article presents two modifications of the Leggett-Williams fixed point theorem, and two applications of these results to a terminal and to a boundary value problem for ordinary differential equations.
Kyriakos G. Mavridis
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Functional expansion - compression fixed point theorem of Leggett-Williams type

Electronic Journal of Differential Equations, 2010
This paper presents a fixed point theorem of compression and expansion of functional type in the spirit of the original fixed point work of Leggett-Williams.
Douglas R. Anderson, Richard I. Avery, Johnny Henderson   +2 more
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Leggett-Williams fixed point theorem type for sums of operators and application in PDEs [PDF]

Differential Equations & Applications, 2021
Summary: In this paper we present an extension of the original version of Leggett-Williams fixed point theorem for a \(k\)-set contraction perturbed by an expansive operator. Our approach is applied to prove the existence of non trivial positive solutions for initial value problems (IVPs for short) covering a class two-dimensional nonlinear wave ...
Georgiev, Svetlin Georgiev, Mebarki, Karima   +1 more
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Existence of Positive Solutions to Boundary Value Problems with Mixed Riemann–Liouville and Quantum Fractional Derivatives

Fractal and Fractional, 2023
In this paper, by using the Leggett–Williams fixed-point theorem, we study the existence of positive solutions to fractional differential equations with mixed Riemann–Liouville and quantum fractional derivatives.
Nemat Nyamoradi, Sotiris K. Ntouyas, Jessada Tariboon   +2 more
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A Dual of the Compression-Expansion Fixed Point Theorems

Fixed Point Theory and Applications, 2007
This paper presents a dual of the fixed point theorems of compression and expansion of functional type as well as the original Leggett-Williams fixed point theorem. The multi-valued situation is also discussed.
Donal O'Regan, Johnny Henderson, Richard Avery   +2 more
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Leggett–Williams norm-type fixed point theorems for multivalued mappings

Applied Mathematics and Computation, 2007
The authors present some generalizations of the Krasnoselskij--Leggett--Williams fixed point theorem for cone expansions and compressions [see \textit{R.\,W.\thinspace Leggett} and \textit{L.\,R.\thinspace Williams}, J.~Math.\ Anal.\ Appl.\ 76, 91--97 (1980; Zbl 0448.47044)] to the case of compact and condensing type multivalued maps with convex values.
O'Regan, Donal, Zima, Mirosława
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Fixed point theorem utilizing operators and functionals

Electronic Journal of Qualitative Theory of Differential Equations, 2012
This paper presents a fixed point theorem utilizing operators and functionals in the spirit of the original Leggett-Williams fixed point theorem which is void of any invariance-like conditions.
Douglas Anderson, Richard Avery, Johnny Henderson, Xueyan Liu   +3 more
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Some fixed point theorems of Leggett-Williams type

Rocky Mountain Journal of Mathematics, 2011
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Avery, Richard, Anderson, Douglas, Henderson, Johnny   +2 more
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On the Existence of Positive Solutions of Resonant and Nonresonant Multipoint Boundary Value Problems for Third-Order Nonlinear Differential Equations

Abstract and Applied Analysis, 2013
Positive solutions for a kind of third-order multipoint boundary value problem under the non-resonant conditions and the resonant conditions are considered. In the nonresonant case, by using Leggett-Williams fixed-point theorem, the existence of at least
Liu Yang, Chunfang Shen, Dapeng Xie, Xiping Liu   +3 more
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Positive Solutions for Resonant and Nonresonant Nonlinear Third-Order Multipoint Boundary Value Problems

Abstract and Applied Analysis, 2013
Positive solutions for a kind of third-order multipoint boundary value problem under the nonresonant conditions and the resonant conditions are considered.
Liu Yang, Chunfang Shen, Dapeng Xie
doaj   +1 more source