Results 21 to 30 of about 355 (125)
The Lusin Theorem and Horizontal Graphs in the Heisenberg Group
Analysis and Geometry in Metric Spaces, 2013 In this paper we prove that every collection of measurable functions fα , |α| = m, coincides a.e. withmth order derivatives of a function g ∈ Cm−1 whose derivatives of order m − 1 may have any modulus of continuity weaker than that of a Lipschitz ...
Hajłasz Piotr, Mirra Jacob
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On the degree of compactness of embeddings between weighted modulation spaces
Journal of Function Spaces, Volume 6, Issue 3, Page 303-317, 2008., 2008 The paper investigates the asymptotic behaviour of entropy and approximation numbers of compact embeddings between weighted modulation spaces.
Aicke Hinrichs +3 more
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Advanced Nonlinear Studies, 2021 The concentration-compactness principle for the Trudinger–Moser-type inequality in the Euclidean space was established crucially relying on the Pólya–Szegő inequality which allows to adapt the symmetrization argument.
Li Jungang, Lu Guozhen, Zhu Maochun
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On dilation operators and sampling numbers
Journal of Function Spaces, Volume 6, Issue 1, Page 17-46, 2008., 2008 We consider the dilation operators Tk : f → f(2k.) in the frame of Besov spaces Bpqs(ℝd) with 1 ≤p, q ≤ ∞. If s > 0, Tk is a bounded linear operator from Bpqs(ℝd) into itself and there are optimal bounds for its norm, see [4, 2.3.1]. We study the situation in the case s = 0, an open problem mentioned also in [4]. It turns out, that new effects based on
Jan Vybíral, Hans Triebel
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Hardy inequalities and Caffarelli-Kohn-Nirenberg inequalities with radial derivative
Journal of Mathematical Inequalities, 2020 In this paper, we study several inequalities of Hardy and Caffarelli-Kohn-Nirenberg type. We set up some optimal versions of these inequalities using the radial derivatives or the convex combinations of the full gradient and its radial part.
Tuan Duy Nguyen, L. Phi, W. Yin
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On the boundedness of operators in LP(ιq) and Triebel‐Lizorkin Spaces
Journal of Function Spaces, Volume 6, Issue 2, Page 177-186, 2008., 2008 Given a bounded linear operator T : LPO(ℝn) → Lp1(ℝn), we state conditions under which T defines a bounded operator between corresponding pairs of Lp(ℝn; ιq) spaces and Triebel‐Lizorkin spaces Fp,qs(ℝn). Applications are given to linear parabolic equations and to Schrödinger semigroups.
João Pedro Boto, Hans Triebel
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Advanced Nonlinear Studies, 2023 Let II be a bounded interval of R{\mathbb{R}} and λ1(I){\lambda }_{1}\left(I) denote the first eigenvalue of the nonlocal operator (−Δ)14{(-\Delta )}^{\tfrac{1}{4}} with the Dirichlet boundary.
Chen Lu, Wang Bohan, Zhu Maochun
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Zero-order Mehler-Fock transform and Sobolev-type space
Mathematical Inequalities & Applications, 2019 The present paper is devoted to the study of the Mehler-Fock transform with index as the Legendre function of first kind. Continuity property of the Mehler-fock transform on the test function spaces Λα and Gα is given.
A. Prasad, U. K. Mandal, S. Verma
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On extremals for the Trudinger-Moser inequality with vanishing weight in the N-dimensional unit ball
, 2020 In this paper, we study the extremal function for the Trudinger-Moser inequality with vanishing weight in the unit ball B⊂RN (N 3). To be exact, let S be the set of all decreasing radially symmetrical functions and αN = Nω 1/(N−1) N−1 , where ωN−1 is the
Mengjie Zhang
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On the trace space of a Sobolev space with a radial weight
Journal of Function Spaces, Volume 6, Issue 3, Page 259-276, 2008., 2008 Our concern in this paper lies with trace spaces for weighted Sobolev spaces, when the weight is a power of the distance to a point at the boundary. For a large range of powers we give a full description of the trace space.
Helmut Abels +3 more
wiley +1 more source