Results 51 to 60 of about 601 (93)
Nonzero positive solutions of a multi-parameter elliptic system with functional BCs
, 2017 We prove, by topological methods, new results on the existence of nonzero positive weak solutions for a class of multi-parameter second order elliptic systems subject to functional boundary conditions. The setting is fairly general and covers the case of
Infante, Gennaro
core +1 more source
On Almost (α, θρ)‐Contractions on Quasimetric Space and Their Fixed Points
Journal of Mathematics, Volume 2025, Issue 1, 2025.In this paper, we introduce the concept of almost (α, θρ)‐contraction mappings on quasimetric spaces. Then, under certain conditions, we present some fixed‐point results for almost (α, θρ)‐contraction mappings with respect to ω and γ on both left K‐complete and left M‐complete quasimetric spaces.
Gonca Durmaz Güngör +4 more
wiley +1 more source
A fixed point theorem for contraction mappings
International Journal of Mathematics and Mathematical Sciences, Volume 5, Issue 2, Page 301-304, 1982., 1981 Let S be a closed subset of a Banach space E and f : S → E be a strict contraction mapping. Suppose there exists a mapping h : S → (0, 1] such that (1 − h(x))x + h(x)f(x) ∈ S for each x ∈ S. Then for any x0 ∈ S, the sequence {xn} in S defined by xn+1 = (1 − h(xn))xn + h(xn)f(xn), n ≥ 0, converges to a u ∈ S. Further, if ∑h(xn) = ∞, then f(u) = u.
V. M. Sehgal
wiley +1 more source
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2019 The aim of this paper is to introduce Ciric-Suzuki type quasi-contractive multivalued operators and to obtain the existence of fixed points of such mappings in the framework of b-metric spaces.
Alolaiyan Hanan +2 more
doaj +1 more source
Some fixed point theorems for set valued directional contraction mappings
International Journal of Mathematics and Mathematical Sciences, Volume 3, Issue 3, Page 455-460, 1980., 1980 Let S be a subset of a metric space X and let B(X) be the class of all nonempty bounded subsets of X with the Hausdorff pseudometric H. A mapping F : S → B(X) is a directional contraction iff there exists a real α ∈ [0, 1) such that for each x ∈ S and y ∈ F(x), H(F(x), F(z)) ≤ αd(x, z) for each z ∈ [x, y]∩S, where [x, y] = {z ∈ X : d(x, z) + d(z, y ...
V. M. Sehgal
wiley +1 more source
Revisiting of some outstanding metric fixed point theorems via E-contraction
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2018 In this paper, we introduce the notion of α-ψ-contractive mapping of type E, to remedy of the weakness of the existing contraction mappings. We investigate the existence and uniqueness of a fixed point of such mappings.
Fulga Andreea, Karapınar Erdal
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The modified Ishikawa iteration process with errors in CAT(0) spaces
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2020 In this article, Δ-convergence and strong convergence of the modified Ishikawa iteration process with errors are established for continuous mappings of asymptotically nonexpansive type in CAT(0) spaces. Our results extend and improve the previous results
Ranjbar Sajad
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A pointwise contraction criteria for the existence of fixed points
International Journal of Mathematics and Mathematical Sciences, Volume 2, Issue 3, Page 473-480, 1979., 1979 Let S be a subset of a metric space (X, d) and T : S → X be a mapping. In this paper, we define the notion of lower directional increment QT(x, y] of T at x ∈ S in the direction of y ∈ X and give sufficient conditions for T to have a fixed point when QT(x, Tx] < 1 for each x ∈ S. The results herein generalize the recent theorems of Clarke (Caned. Math.
V. M. Sehgal
wiley +1 more source
Orthogonal stability of the generalized quadratic functional equations in the sense of Rätz
Demonstratio Mathematica, 2019 Let (X, ⊥) be an orthogonality module in the sense of Rätz over a unital Banach algebra A and Y be a real Banach module over A. In this paper, we apply the alternative fixed point theorem for proving the Hyers-Ulam stability of the orthogonally ...
Aiemsomboon Laddawan +1 more
doaj +1 more source
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2014 In this paper, we study some tripled fixed and coincidence point theorems for two mappings F : X × X × X → X and ɡ : X → X satisfying a nonlinear contraction based on ϕ-maps. Our results extend and improve many existing results in the literature.
Shatanawi Wasfi +2 more
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