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Habilitation " Spline Approximation and generalized Lipschitz
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Books:
Approximationsprozesse und Interpolationsmethoden.
BI-Hochschulskripten 826/826a , Mannheim 1968 (with P.L.Butzer).
Approximation Theory.Proc. Internat. Colloquium,
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Unpublished manuscripts
Approximation by piecewise polynomials with variable degrees and knots.
SFB 72 - Preprint Nr.316, 1980.
0(h2n) approximation by
piecewise polynomial curves of degree n in the plane .
Manuscript 1995
Weighted Jackson and Bernstein Inequalities.
SFB 611 - Preprint Nr.120, 2002.
Approximation Processes,
Norm Equivalences and Applications to Preconditioning. SFB 611 -
Preprint Nr., 2004.
List of research areas
Approximation Theory in Banach Spaces
Fourier Analysis and Approximation
Interpolation Theory of Banach Spaces
Rate of approximation by Splines (fixed knots)
Multivariate Splines
Approximation with variable degree and knots
Approximation by rational functions
Parametric Approximation
Rate of Approximation by parametric polynomial curves
Stability of the B-Spline- and Bernstein-Bezier Basis
Robust Preconditioning for Additive Multilevel Schemes
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