Sätze des Khintchine Typus für Mengenfunktionen
Smoothness of vector sums of plane convex sets.
Spaces of sequences, sampling theorem, and functions of exponential type
We introduce certain spaces of sequences which can be used to characterize spaces of functions of exponential type. We present a generalized version of the sampling theorem and a "nonorthogonal wavelet decomposition" for the elements of these spaces of sequences. In particular, we obtain a discrete version of the so-called φ-transform studied in [6] [8]. We also show how these new spaces and the corresponding decompositions can be used to study multiplier operators on Besov spaces.
Stability in the -norm and -norm of classes of Lipschitz functions of one variable.
Summation processes viewed from the Fourier properties of continuous unimodular functions on the circle
The main purpose of this article is to give a new method and new results on a very old topic: the comparison of the Riemann processes of summation (R,κ) with other summation processes. The motivation comes from the study of continuous unimodular functions on the circle, their Fourier series and their winding numbers. My oral presentation in Poznań at the JM-100 conference exposed the ways by which this study was developed since the fundamental work of Brézis and Nirenberg on the topological degree...