Results 1 to 10 of about 147 (97)

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
openaire   +4 more sources

Fixed point theorem of Leggett–Williams type and its application

Journal of Mathematical Analysis and Applications, 2004
One of the generalizations of Krasnoselskii's theorem on cone expansion and compression was obtained in [\textit{R. W. Leggett, L. R. Williams}, J. Math. Anal. Appl., Vol. 76, 91--97 (1980; Zbl 0448.47044)]. In the present paper, the author proves the following Leggett-Williams type theorem: Theorem.
Donal O'Regan, Miroslawa Zima
exaly   +5 more sources

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
openaire   +5 more sources

Existence of Three Solutions to Integral and Discrete Equations via the Leggett Williams Fixed Point Theorem

Rocky Mountain Journal of Mathematics, 2001
Criteria are developed for the existence of three nonnegative solutions to integral and discrete equations. The strategy involves using the Leggett Williams fixed point theorem.
Agarwal, R.P., O'Regan, D.
openaire   +6 more sources

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
doaj   +2 more sources

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
doaj   +2 more sources

Positive Solutions for Boundary Value Problems of Second-Order Functional Dynamic Equations on Time Scales

Advances in Difference Equations, 2009
Criteria are established for existence of least one or three positive solutions for boundary value problems of second-order functional dynamic equations on time scales.
Ilkay Yaslan Karaca
doaj   +2 more sources

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
doaj   +2 more sources

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
doaj   +1 more source

Boundary value problems of fractional q-difference equations on the half-line

Boundary Value Problems, 2019
In this paper, we consider the boundary value problem of a class of nonlinear fractional q-difference equations involving the Riemann–Liouville fractional q-derivative on the half-line.
Kuikui Ma, Xinhui Li, Shurong Sun
doaj   +1 more source