Results 61 to 70 of about 2,706 (176)
Barycenters of measures on certain noncompact convex sets [PDF]
Transactions of the American Mathematical Society, 1971 Each norm closed and bounded convex subset K of a separable dual Banach space is, according to a theorem of Bessaga and Pelczynski, the norm closed convex hull of its extreme points. It is natural to expect that this theorem may be reformulated as an integral representation theorem, and in this connection we have examined the extent to which the ...
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Some Paranormed Sequence Spaces Which Involve Arithmetic Divisor Sum Function
Journal of Function Spaces, Volume 2026, Issue 1, 2026.Let Dr, r ≥ 0, be a triangle and q = (qj) be a bounded sequence of strictly positive numbers. In this paper, we study the algebraic and topological properties of the paranormed sequence space ℓDr,q, generated by the triangle Dr over Maddox′s space ℓ(q). We identify the Schauder basis as well as the α‐, β‐, and γ‐duals of the space ℓDr,q. One section is
Ting Gan +5 more
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A POINT OF VIEW ON MEASURES OF NONCOMPACTNESS
Demonstratio Mathematica, 1993 The author presents a general scheme of construction of measures of noncompactness and an example of application in the theory of nonlinear differential equations.
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A MEASURE OF NONCOMPACTNESS IN SEQUENCE BANACH SPACES
Demonstratio Mathematica, 1995 A measure of noncompactness is introduced and shown to be equivalent to the Hausdorff measure of noncompactness.
Martinón, Antonio, Sadarangani, Kishin
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On the Stability of Fractional Integro‐Differential Equations of Ψ‐Hilfer Type
Journal of Function Spaces, Volume 2026, Issue 1, 2026.In this article, we investigate some properties such as the existence, uniqueness, and Ulam–Hyers–Rassias stability for the fractional Volterra–Fredholm integrodifferential equations of Ψ‐Hilfer type with boundary conditions. We prove the desired results by using the Banach fixed point theorem and the Schauder fixed point theorem.
Malayin A. Mohammed +3 more
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Positive Solutions for the Initial Value Problems of Fractional Evolution Equation
Journal of Function Spaces and Applications, 2013 This paper discusses the existence of positive solutions for the initial value problem of fractional evolution equation with noncompact semigroup , ; in a Banach space , where denotes the Caputo fractional derivative of order , is a closed linear ...
Yue Liang, Yu Ma, Xiaoyan Gao
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Measures of Noncompactness in Regular Spaces
Canadian Mathematical Bulletin, 2014 AbstractPrevious results by the author on the connection between three measures of noncompactness obtained for Lp are extended to regular spaces of measurable functions. An example is given of the advantages of some cases in comparison with others. Geometric characteristics of regular spaces are determined.
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Measure of weak noncompactness under complex interpolation [PDF]
Studia Mathematica, 2001 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Kryczka, Andrzej, Prus, Stanisław
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Geraghty–𝔽‐Contraction Type Darbo Fixed‐Point Theorems With an Application
Journal of Mathematics, Volume 2026, Issue 1, 2026.In this study, Darbo’s fixed‐point theorem is extended by employing Geraghty–𝔽‐contractions on Banach spaces. The obtained results are then applied to establish the existence of solutions for a fractional integral equation in the space C([0, ς]), equipped with the Hausdorff measure of noncompactness. To support and validate the main theorems presented,
Samira Hadi Bonab +5 more
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Nonlinear Integrodifferential Equations of Mixed Type in Banach Spaces
International Journal of Mathematics and Mathematical Sciences, 2007 We prove two existence theorems for the integrodifferential equation of mixed type: x'(t)=f(t,x(t),∫0tk1(t,s)g(s,x(s))ds,∫0ak2(t,s)h(s,x(s))ds), x(0)=x0, where in the first part of this paper f, g, h, x are functions with values in a Banach space E and ...
Aneta Sikorska-Nowak, Grzegorz Nowak
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