Results 31 to 40 of about 65 (61)
Local expansions and accretive mappings
International Journal of Mathematics and Mathematical Sciences, Volume 6, Issue 3, Page 419-429, 1983., 1983 Let X and Y be complete metric spaces with Y metrically convex, let D ⊂ X be open, fix u0 ∈ X, and let d(u) = d(u0, u) for all u ∈ D. Let f : X → 2Y be a closed mapping which maps open subsets of D onto open sets in Y, and suppose f is locally expansive on D in the sense that there exists a continuous nonincreasing function c : R+ → R+ with ∫+∞c(s)ds =
W. A. Kirk
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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
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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
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Topological Transversality Principles and General Coincidence Theory
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2017 This paper presents general topological coincidence principles for multivalued maps defined on subsets of completely regular topological spaces.
O’Regan Donal
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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
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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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Abstract Leray–Schauder Type Alternatives and Extensions
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2019 We present a Leray–Schauder type alternative for a general class of maps. This enables us to obtain some Birkhoff–Kellogg type results and a Furi–Pera result.
O’Regan Donal
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Leray–Schauder Alternatives for Maps Satisfying Countable Compactness Conditions
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2019 In this paper we present Leray–Schauder alternatives for a general class of Mönch type maps.
O’Regan Donal
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Approximating fixed points of nonexpansive and generalized nonexpansive mappings
, 1991 International Journal of Mathematics and Mathematical Sciences, Volume 16, Issue 1, Page 81-86, 1993.
M. Maiti, B. Saha
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Interpolative Rus-Reich-Ćirić Type Contractions via Simulation Functions
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2019 In this paper, we introduce the notion of interpolative Rus-Reich-Ćirić type 𝒵- contractions in the setting of complete metric space. We also consider some immediate consequences of our main results.
Karapınar Erdal, Agarwal Ravi P.
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