68 citations · 117 across the 9 of their papers we have counts for
6 papers · 1 filter
Pointwise Multipliers for Besov Spaces with Only Logarithmic Smoothness
Ziwei Li, Winfried Sickel, Dachun Yang +1
In this article, we establish a characterization of the set of all pointwise multipliers of Besov spaces wi…
-Numbers of Embeddings of Weighted Wiener Algebras
Van Dung Nguyen, Van Kien Nguyen, Winfried Sickel
In this paper we study the asymptotic behavior of Kolmogorov, approximation, Bernstein and Weyl numbers of embeddings $ \mathcal{A}^{s,r}_{\rm mix}(\mathbb{T}^d) \to L_2(\mathbb{T}…
Properties of Kondratiev spaces
Stephan Dahlke, Markus Hansen, Cornelia Schneider +1
In this paper, we investigate Kondratiev spaces on domains of polyhedral type. In particular, we will be concerned with necessary and sufficient conditions for continuous and compa…
On a Problem of Jaak Peetre Concerning Pointwise Multipliers of Besov Spaces
Van Kien Nguyen, Winfried Sickel
We characterize the set of all pointwise multipliers of the Besov spaces under the restrictions and .
Optimal approximation of multivariate periodic Sobolev functions in the sup-norm
Fernando Cobos, Thomas Kühn, Winfried Sickel
Using tools from the theory of operator ideals and s-numbers, we develop a general approach to transfer estimates for -approximation of Sobolev functions into estimates for $…
The Characterization of Radial Subspaces of Besov- and Lizorkin-Triebel Spaces by Differences
Winfried Sickel, Leszek Skrzypczak, Jan Vybiral
We continue our earlier investigations of radial subspaces of Besov and Lizorkin-Triebel spaces on . This time we study characterizations of these subspaces by differences.