Results 21 to 30 of about 2,149 (181)
Fixed point theorem utilizing operators and functionals [PDF]
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 +3 more
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Triple positive solutions of BVP for second order ODE with one dimensional Laplacian on the half line [PDF]
Electronic Journal of Qualitative Theory of Differential Equations, 2012 By applying Leggett-Williams fixed point theorem in a suitably constructed cone, we obtain the existence of at least three bounded positive solutions for a boundary value problem on the half line.
Yuji Liu, Patricia J. Y. Wong
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Three symmetric positive solutions of fourth-order singular nonlocal boundary value problems [PDF]
Electronic Journal of Qualitative Theory of Differential Equations, 2011 In this paper, we study the existence of three positive solutions of fourth-order singular nonlocal boundary value problems. We show that there exist triple symmetric positive solutions by using Leggett-Williams fixed-point theorem.
Fuyi Xu
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Multiple positive solutions for the system of higher order two-point boundary value problems on time scales [PDF]
Electronic Journal of Qualitative Theory of Differential Equations, 2009 In this paper, we establish the existence of at least three positive solutions for the system of higher order boundary value problems on time scales by using the well-known Leggett-Williams fixed point theorem.
K. Prasad +2 more
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Leggett–Williams norm-type fixed point theorems for multivalued mappings
Journal of Mathematical Analysis and Applications, 2006 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, Mirosława Zima
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Electronic Journal of Applied MathematicsThis paper examines the application of fixed point index theory to set-valued mappings in ordered Banach spaces, with a specific focus on Leggett-Williams type fixed point theorems. The study provides novel conditions for the existence of one and multiple fixed points under a range of assumptions.
Quang ND
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Electronic Journal of Differential Equations, 2000 The authors deal with the existence of three positive solutions to the so-called Lidstone BVP \[ y^{(4)}=f(y,-y''), 0\leq t\leq 1, y(0)=y''(0)=y(1)=y''(1)=0. \] These solutions are required to be symmetric in the sense that they satisfy \(y(t)=y(1-t),\) for all \(t\in[0,1].\) The paper is organized as follows: In section 2 the authors provide some ...
Richard I. Avery +2 more
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An extension of Leggett-Williams norm-type theorem for coincidences and its application
, 2011 The author proves several modifications of the Leggett-Williams norm-type theorems for coincidences due to \textit{D. O'Regan} and \textit{M. Zima} [Arch. Math. 87, No. 3, 233--244 (2006; Zbl 1109.47051)]. Namely, the existence of positive solutions for the equation \(Mx=Nx\) is considered.
Aijun Yang
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A review of migratory Alosidae marine ecology in the northwest Atlantic. [PDF]
J Fish BiolAbstract Migratory animals play a crucial role in connecting distinct habitats by transferring matter and energy across ecosystem boundaries. In the North Atlantic, anadromous species exemplify this through their movement between freshwater and marine environments.
Brown CR +8 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 +2 more
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