Results 1 to 10 of about 27,509 (180)

Riesz means on homogeneous trees [PDF]

Concrete Operators, 2021
Let 𝕋 be a homogeneous tree. We prove that if f ∈ Lp(𝕋), 1 ≤ p ≤ 2, then the Riesz means SzR (f) converge to f everywhere as R → ∞, whenever Re z > 0.
Papageorgiou Effie
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Riesz means on symmetric spaces [PDF]

Journal of Mathematical Analysis and Applications, 2021
Let $X$ be a non-compact symmetric space of dimension $n$. We prove that if $f\in L^{p}(X)$, $1\leq p\leq 2$, then the Riesz means $S_{R}^{z}\left( f\right)$ converge to $f$ almost everywhere as $R\rightarrow \infty $, whenever $\operatorname{Re}z>\left( n-\frac{1}{2}\right) \left( \frac{2}{p}-1\right) $.
A. Fotiadis, E. Papageorgiou
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A Matrix Transform Technique for Distributed-Order Time-Fractional Advection–Dispersion Problems

Fractal and Fractional, 2023
Invoking the matrix transfer technique, we propose a novel numerical scheme to solve the time-fractional advection–dispersion equation (ADE) with distributed-order Riesz-space fractional derivatives (FDs).
Mohammadhossein Derakhshan, Ahmed S. Hendy, António M. Lopes, Alexandra Galhano, Mahmoud A. Zaky   +4 more
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Higher-Order Riesz Transforms in the Inverse Gaussian Setting and UMD Banach Spaces

Journal of Function Spaces, 2021
In this paper, we study higher-order Riesz transforms associated with the inverse Gaussian measure given by πn/2ex2dx on ℝn. We establish Lpℝn,ex2dx-boundedness properties and obtain representations as principal values singular integrals for the higher ...
Jorge J. Betancor, Lourdes Rodríguez-Mesa   +1 more
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Weak-type endpoint bounds for Bochner–Riesz means for the Hermite operator

Comptes Rendus. Mathématique, 2022
We obtain weak-type $(p, p)$ endpoint bounds for Bochner–Riesz means for the Hermite operator $H = -\Delta + |x|^2$ in ${\mathbb{R}}^n, n\ge 2$ and for other related operators, for $1\le p\le 2n/(n+2)$, extending earlier results of Thangavelu and of ...
Chen, Peng, Li, Ji, Ward, Lesley, Yan, Lixin   +3 more
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APPROXIMATION BY LINEAR MEANS OF FOURIER SERIES AND REALIZATION FUNCTIONALS IN WEIGHTED ORLICZ SPACES

Проблемы анализа, 2022
Using one-sided Steklov means, we introduce a new modulus of smoothness in weighted Orlicz spaces and state its equivalence with a special 𝐾-functional. We prove Stechkin-Nikol’skii-type inequality for trigonometric polynomials and direct estimates for
S. S. Volosivets
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Degree of convergence of the functions of trigonometric series in Sobolev spaces and its applications

Journal of Inequalities and Applications, 2022
In this paper, we study the degree of convergence of the functions of Fourier series and conjugate Fourier series in Sobolev spaces using Riesz means. We also study some applications of our main results and observe that our results are much better than ...
H. K. Nigam, Saroj Yadav
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On the deformed Besov-Hankel spaces [PDF]

Opuscula Mathematica, 2020
In this paper we introduce function spaces denoted by \(BH_{\kappa,\beta}^{p,r}\) (\(0\lt\beta\lt 1\), \(1\leq p, r \leq +\infty\)) as subspaces of \(L^p\) that we call deformed Besov-Hankel spaces.
Salem Ben Saïd, Mohamed Amine Boubatra, Mohamed Sifi   +2 more
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On Riesz Means of Eigenvalues [PDF]

Communications in Partial Differential Equations, 2011
In this article we prove the equivalence of certain inequalities for Riesz means of eigenvalues of the Dirichlet Laplacian with a classical inequality of Kac. Connections are made via integral transforms including those of Laplace, Legendre, Weyl, and Mellin, and the Riemann-Liouville fractional transform.
Harrell, Evans M., Hermi, Lotfi
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Some inequalities related to strong convergence of Riesz logarithmic means

Journal of Inequalities and Applications, 2020
In this paper we derive a new strong convergence theorem of Riesz logarithmic means of the one-dimensional Vilenkin–Fourier (Walsh–Fourier) series. The corresponding inequality is pointed out and it is also proved that the inequality is in a sense sharp,
D. Lukkassen, L. E. Persson, G. Tephnadze, G. Tutberidze   +3 more
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