Results 1 to 10 of about 651 (60)
Quantitative functional calculus in Sobolev spaces [PDF]
Journal of Function Spaces and Applications, 2004 In the frame work of Sobolev (Bessel potential) spaces Hn(Rd,R or C), we consider the nonlinear Nemytskij operator sending a function x∈Rd↦f(x) into a composite function x∈Rd↦G(f(x),x).
Carlo Morosi, Livio Pizzocchero
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Uniformly bounded set-valued Nemytskij operators acting between generalized Hölder function spaces
Open Mathematics, 2012 Abstract We show that the generator of any uniformly bounded set-valued Nemytskij composition operator acting between generalized Hölder function metric spaces, with nonempty, bounded, closed, and convex values, is an affine function.
Matkowski Janusz, Wróbel Małgorzata
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On uniformly continuous Nemytskij operators generated by set-valued functions [PDF]
Aequationes mathematicae, 2010 The properties of superposition operators generated by set-valued functions are studied. The main result is the following. Theorem. Let \(I = [0, 1]\) and \(Y\) be a real normed linear space, \(Z\) be a Banach space and let \(C\) be a convex cone in \(Y\). Assume that \(\gamma: [0, \infty) \rightarrow [0, \infty)\) is continuous at \(0\), \(\gamma(0) =
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On Fréchet-differentiability of Nemytskij operators acting in Hölder spaces [PDF]
Glasgow Mathematical Journal, 1991 In any field of nonlinear analysis Nemytskij operators, the superposition operators generated by appropriate functions, play a crucial part. Their analytic properties depend on the postulated properties of the defining function and on the function space in which they are considered. A rich source for related questions is the monograph by J.
Mehmeti Feli Ali, Serge Nicaise
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Uniformly continuous set-valued composition operators in the space of total φ-bidimensional variation in the sense of Riesz [PDF]
Opuscula Mathematica, 2010 In this paper we prove that if a Nemytskij composition operator, generated by a function of three variables in which the third variable is a function one, maps a suitable large subset of the space of functions of bounded total \(\varphi\)-bidimensional ...
Wadie Aziz +3 more
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On the Autonomous Nemytskij Operator in Hölder Spaces
Zeitschrift für Analysis und ihre Anwendungen, 1999 The paper is devoted to the autonomous Nemytskij operator (superposition operator) in Hölder spaces H^{k+\alpha}[a,b], (k, \alpha) \in \mathbb Z_+ \times [0, 1]. We study acting, continuity, Lipschitz continuity, and Fréchet differentiability conditions. For
Goebel, M., Sachweh, F.
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Coexistence and Segregation for Strongly Competing Species in Special Domains [PDF]
, 2006 We deal with strongly competing multispecies systems of Lotka-Volterra type with homogeneous Dirichlet boundary conditions. For a class of nonconvex domains composed by balls connected with thin corridors, we show the occurrence of pattern formation ...
Conti, Monica, Felli, Veronica
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Sobolev subspaces of nowhere bounded functions [PDF]
, 2016 We prove that in any Sobolev space which is subcritical with respect to the Sobolev Embedding Theorem there exists a closed infinite dimensional linear subspace whose non zero elements are nowhere bounded functions.
Lamberti, PIER DOMENICO +1 more
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Hardy type inequality in variable Lebesgue spaces [PDF]
, 2008 We prove that in variable exponent spaces $L^{p(\cdot)}(\Omega)$, where $p(\cdot)$ satisfies the log-condition and $\Omega$ is a bounded domain in $\mathbf R^n$ with the property that $\mathbf R^n \backslash \bar{\Omega}$ has the cone property, the ...
Rafeiro, Humberto, Samko, Stefan
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Blow-up and global existence for a general class of nonlocal nonlinear coupled wave equations [PDF]
, 2010 We study the initial-value problem for a general class of nonlinear nonlocal coupled wave equations. The problem involves convolution operators with kernel functions whose Fourier transforms are nonnegative.
A. Erkip +20 more
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