Advances in
Multivariate Approximation
1998
Wiley-VCH

edited by

Werner Haußmann,
Universität Duisburg
Kurt Jetter,
Universität Hohenheim
Manfred Reimer,
Universität Dortmund

Contents of Web Page:



Preface

The Third International Conference on Multivariate Approximation at ``Haus Bommerholz'', the guest-house of the University of Dortmund, took place during the week of September 27 through October 2, 1998. It was attended by 50 participants from 18 countries. The program included 10 invited lectures, 25 contributed talks, and two problem sessions. In these Proceedings we collect most of the lectures, suitably prepared by the authors for publication, and carefully peer-refereed.
As was the case for the preceding conferences, the meeting was intended to advance several selected topics from modern aspects of Multivariate Approximation Theory. This time, emphasis was put on the following subjects: Interpolation and Approximation on Spheres and Balls, Approximation by Solutions of Partial Differential Equations, Construction of Node Systems, and Scattered Data Techniques. Leading experts in these areas and quite a number of young researchers made the meeting a stimulating event, with lively discussions and scientific interactions to support and initiate future research.
The editors are grateful to all who have contributed to the success of the conference and to the production of this Proceedings volume. In particular, our thanks go to the Deutsche Forschungsgemeinschaft whose funding made the conference possible, and to the Ministerium für Schule, Weiterbildung, Wissenschaft und Forschung of the Land Nordrhein-Westfalen for sponsoring this volume. We acknowledge the help of the authors and the referees to guarantee publications of high scientific standard, and we thank the WILEY-VCH publishers for their kind cooperation. In addition, we acknowledge the extensive help of Dr. Hermann Hoch and Dipl.-Math. Jörg Zabold (Duisburg) during the production of this Proceedings volume. Finally, we would especially like to thank the conference secretary, Mrs. Lamprecht, and the staff of Haus Bommerholz, for all their help.
May 1, 1999
Werner Haußmann
Kurt Jetter
Manfred Reimer


Acknowledgement

We are deeply indebted to the

                Deutsche Forschungsgemeinschaft (DFG)

whose funding made the conference possible.

The production of this volume was sponsored by the

                Ministerium für Schule und Weiterbildung,

                Wissenschaft und Forschung

                des Landes Nordrhein-Westfalen.

We are grateful for the generous support.

The Editors


Table of Contents

Participants 9
Scientific Program of the Conference 15
Problems of Approximation Theory in Discrete Geometry N. N. Andreev and V. A. Yudin 19
Dense Vector Spaces of Universal Harmonic Functions D. H. Armitage 33
Best One-sided Subharmonic Functions D. H. Armitage and S. J. Gardiner 43
Numerical Stability of Fast Fourier TransformsG. Baszenski, R. Xuefang and M. Tasche 57
The Saturation Theorem for Box Spline Orthogonal ProjectionM. Beska and K. Dziedziul 73
Problem on Monotonic Behaviour of Bernstein OperatorsM. Beska and K. Dziedziul 84
Best One-Sided-Approximation by Blending Functions B. D. Bojanov, D. P. Dryanov,W. Haußmann and G. P. Nikolov 85
On the Asymptotics of Points which Maximize Determinants of the Form L. Bos and U. Maier 107
Besov Regularity for the Stokes Problem F.-J. Delvos 139
Multiscale Modelling from Geopotential DataW. Freeden, O. Glockner and R. Litzenberger 151
On a Family of Orthogonal Wavelets on the Quincunx Grid: Open Regularity QuestionsA. Gottscheber and G. Steidl 175
Average Case Analysis of Numerical Integration P. J. Grabner, P. Liardet and R. F. Tichy 185
Cubature Formulas on SpheresH. König 201
Numerical Calculation of Spherical DesignsU. Maier 213
On Bivariate Spline SpacesG. Nürnberger and F. Zeilfelder 227
Spherical Polynomial Approximations: A SurveyM. Reimer 231
Range Restricted Interpolation by Cubic-Splines on Clough-Tocher J. W. Schmidt 253
Some Error Estimates for Periodic Interpolation of Functions from Besov SpacesW. Sickel and F. Sprengel 269
The Uniform Error of Hyperinterpolation on the Sphere I. H. Sloan and R. S. Womersley 289
Simultaneous Approximation in the Dirichlet SpaceA. Stray 307
The Equivalence between Weighted Moduli of Smoothness on a Simplex and their ApplicationsP.-C. Xuan 321


Participants

  • David Armitage, Department of Pure Mathematics, Queen's University, Belfast BT7 1NN, Northern Ireland
  • Marek Beska, Department of Mathematics, Technical University of Gdansk, Narutowicza 11/12, 80-952 Gdansk, Poland
  • Peter Binev, Institute of Mathematics, Bulgarian Academy of Sciences, Sofia 1090, Bulgaria
  • Heribert BlumFachbereich Mathematik, Universität Dortmund, D-44221 Dortmund, Germany
  • Len Bos, Department of Mathematics and Statistics, University of Calgary, Calgary, Alberta T2N 1N4, Canada
  • Dietrich Braess, Institut für Mathematik, Ruhr-Universität Bochum, D-44780 Bochum, Germany
  • Zbigniew Ciesielski, Mathematical Institute PAN, ul. 23 Abrahama 18,81-825 Sopot, Poland
  • Stephan Dahlke, Institut für Geometrie und Praktische Mathematik, RWTH Aachen, Templergraben 55, D-52062 Aachen, Germany
  • Wolfgang Dahmen, Institut für Geometrie und Praktische Mathematik, RWTH Aachen, Templergraben 55, D-52062 Aachen, Germany
  • Oleg Davydov, Fachbereich Mathematik, Universität Dortmund, D-44221 Dortmund, Germany
  • Franz-Jürgen Delvos, Fachbereich 6 - Mathematik, Universität-GH-Siegen, Hölderlinstraße 3. D-57076 Siegen, Germany
  • Stefano de Marchi, Dipartimento di Matemàtica e Informàtica, Università di Udine, via della Scienze 206, I-33100 Udine, Italy
  • Uwe Depczynski, Institut für Angewandte Mathematik und Statistik,Universität Hohenheim, D-70593 Stuttgart, Germany
  • Michael Felten, Fachbereich Mathematik, Universität Dortmund, D-44221 Dortmund, Germany
  • Willi Freeden, AG Geomathematik,Universität Kaiserslautern, Postfach 3049, D-67653 Kaiserslautern, Germany
  • Stephen J. Gardiner, University College Dublin, Dublin 4, Ireland
  • Werner Haußmann, Fachbereich Mathematik, Universität Duisburg, D-47048 Duisburg, Germany
  • Kurt Jetter, Institut für Angewandte Mathematik und Statistik, Universität Hohenheim, D-70593 Stuttgart, Germany
  • Lavi Karp, Department of Mathematics, University of Stockholm, S-10691 Stockholm, Sweden
  • John Klinkhammer, Fachbereich Mathematik, Universität Duisburg, D-47048 Duisburg, Germany
  • Hermann König, Mathematisches Seminar, Universität Kiel, Ludewig-Meyn-Str. 4, D-24098 Kiel, Germany
  • Ognyan Kounchev, Institute of Mathematics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str. 8, BG-1113 Sofia, Bulgaria
  • Angela Kunoth, Institut für Geometrie und Praktische Mathematik, RWTH Aachen, Templergraben 55, D-52062 Aachen, Germany
  • Alain Le Méhauté, Département de Mathématiques, Université de Nantes, 2 Rue de la Houssinière, F-44072 Nantes Cedex, France
  • Detlef Mache, Fachbereich Mathematik, Universität Dortmund, D-44221 Dortmund, Germany
  • Ulrike Maier, Fachbereich Mathematik, Universität Dortmund, D-44221 Dortmund, Germany
  • Marie-Laurence Mazure, LMC - IMAG, Université Joseph Fourier, BP 53 X, F-38041 Grenoble, France
  • Volker Michel, AG Geomathematik, Universität Kaiserslautern, Postfach 3049, D-67653 Kaiserslautern, Germany
  • H. Michael Möller, Fachbereich Mathematik, Universität Dortmund, D-44221 Dortmund, Germany
  • Manfred W. Müller, Fachbereich Mathematik, Universität Dortmund, D-44221 Dortmund, Germany
  • Günther Nürnberger, Lehrstuhl für Mathematik IV, Universität Mannheim, D-68131 Mannheim, Germany
  • Fernando Pérez-Gonzaléz, Departamento de Analisis Matematico, Universidad de Laguna, E-28271 La Laguna, Tenerife, Spain
  • Gerlind Plonka, Fachbereich Mathematik, Universität Duisburg, D-47048 Duisburg, Germany
  • Jürgen Prestin, GSF-Forschungszentrum, Postfach 1129, D-86758 Neuherberg, Germany
  • Manfred Reimer, Fachbereich Mathematik, Universität Dortmund, D-44221 Dortmund, Germany
  • Sherman D. Riemenschneider, Department of Mathematical Sciences, University of Alberta, Edmonton, Alberta T6G 2G1, Canada
  • Robert Schaback, Institut für Numerische und Angewandte Mathematik, Universität Göttingen, D-37083 Göttingen, Germany
  • Jochen W. Schmidt, Institut für Numerische Mathematik, Technische Universität Dresden, D-01062 Dresden, Germany
  • Jacob J. Seidel, Vesalinslaan 26, 5644 HK Eindhoven, Netherlands
  • Ian H. Sloan, School of Mathematics, University of New South Wales, Sydney, Australia 2052
  • Frauke Sprengel, CWI, Kruislaan 413, P.O.Box 94079, 1090 GB Amsterdam, Netherlands
  • Gabriele Steidl, Fachbereich Mathematik, Universität Mannheim, D-68131 Mannheim, Germany
  • Joachim Stöckler, Institut für Angewandte Mathematik und Statistik, Universität Hohenheim, D-70593 Stuttgart, Germany
  • Arne Stray , Matematisk Institutt, Universitetet i Bergen, Johs. Bruns Gt. 12, 5020 Bergen, Norway
  • Manfred Tasche, Fachbereich Mathematik, Universität Rostock, D-18051 Rostock, Germany
  • Robert F. Tichy, Institut für Mathematik A, Technische Universität Graz, Steyrergasse 30, A-8010 Graz, Austria
  • Joseph D. Ward, Department of Mathematics, Texas A&M University, College Station, TX 77843-3368, USA
  • Pei-Cai Xuan, Department of Computer Sciences, Shaoxing College of Arts and Sciences, Shaoxing, Zhejiang 312 000, P.R.China
  • Vladimir A. Yudin, Moscow Institute of Power Engineering, Department of Higher Mathematics, Krasnokazarmennaya 14, Moscow 105 835, Russia
  • Georg Zimmermann, Institut für Angewandte Mathematik und/a Statistik, Universität Hohenheim, D-70593 Stuttgart, Germany

    Scientific Program of the Conference

    Monday, September 28:

    Opening Session: Chair K. Jetter

    9:00 Opening of the Conference

    9:30 - 10:30 R. F. Tichy: Point Distributions, Discrepancy and Applications

    Morning Session: Chair R. F. Tichy

    11:00 - 11:30 V. A. Yudin: Extremal Dispositions of Points on the Sphere and the Torus

    11:30 - 12:00 J. J. Seidel: Spherical Designs

    12:00 - 12:30 U. Maier: Numerical Calculation of Spherical Designs

    Afternoon Session: Chair: A. Stray

    16:00 - 17:00 F. Pérez-Gonzalez: Approximation in the L1-Norm by Element of a Uniform Algebra

    17:00 - 17:30 S. J. Gardiner: Best One-Sided L1-Approximation by Harmonic and Subharmonic Functions

    17:30 - 18:00 D. H. Armitage: Universal Harmonic Functions

    Tuesday, September 29:

    1st Morning Session: Chair: J. W. Schmidt

    9:00 - 10:00 G. Plonka: A New Factorization of Mask Symbols of Scaling Vectors

    2nd Morning Session: Chair: H. König

    10:00 - 10:30 J. Prestin: Polynomial Wavelets

    11:00 - 11:30 H. M. Möller: H-Bases: A Tool for Polynomial Interpolation and System Solving

    11:30 - 12:30 L. Karp: Generalized Newtonian Potential and its Applications

    Afternoon Session: Chair: J. D. Ward

    16:00 - 17:00 W. Freeden: Inverse Multiscale Modelling of the Geopotential

    17:00 - 17:30 V. Michel: A New Way of Reconstructing the Density of the Earth from Geodetic Measurements

    17:30 - 18:00 J. W. Schmidt: Scattered Data Interpolation with Rational Splines on PS Refinements

    Evening Session: Chair: G. Plonka

    19:30 - 20:00 A. Faul: Proof of Convergence of an Iterative Technique for Thin Plate Splines in Two Dimensions

    20:00 - 20:30 A. Le Méhauté : Inf-Convolution and Radial Basis Functions

    20:30 - 21:00 F.-J. Delvos: Optimal Interpolation in Multivariate Periodic Hilbert Spaces

    21:00 - 21:30 1st Problem Session

    Wednesday, September 30:

    1st Morning Session: Chair: S. Riemenschneider

    9:00 - 10:00 W. Dahmen: Adaptive Wavelet Methods for Elliptic Problems - Convergence Rates

    10:00 - 10:30 A. Kunoth: Multiscale Galerkin Methods for Elliptic PDEs - Appending Boundary Conditions by Lagrange Multipliers and Fictitious Domains

    2nd Morning Session: Chair: D. Braess

    11:00 - 11:30 S. Dahlke: Recent Results on Besov Regularity for Elliptic Boundary Value Problems

    11:30 - 12:00 P.-C. Xuan: The Equivalence Between the Weighted K-Functional and Moduli of Smoothness on the Simplex and Their Applications

    12:00 - 12:30 F. Sprengel: Interpolation on Sparse Grids and Nikol'ski-Besov Spaces of Dominating Mixed Smoothness

    Thursday, October 1:

    1st Morning Session: Chair: Z. Ciesielski

    9:00 - 10:00 M. Reimer: Spherical Polynomial Approximation: A Survey

    10:00 - 10:30 L. Bos: On the Asymptotics of Fekete Points for Radial Basis Functions

    2nd Morning Session: Chair: L. Bos

    11:00 - 11:30 S. de Marchi: On the Limit under Scaling of Polynomial Lagrange Interpolation on Spheres and Analytic Manifolds

    11:30 - 12:30 A. Stray: Simultaneous Approximation in the Dirichlet Space

    Afternoon Session: Chair: G. Nürnberger

    16:00 - 17:00 H. König: Cubature Formulas on Spheres

    17:00 - 17:30 M. Beska: The Saturation Problem for some Classical Operators

    17:30 - 18:00 S. D. Riemenschneider: Cardinal Interpolation by Gaussian Radial Basis Functions: Behaviour as

    Evening Session: Chair: M. Reimer

    19:30 - 20:00 M. Tasche: How Stable are Fast Cosine Transforms?

    20:00 - 21:00 2nd Problem Session

    Friday, October 4:

    1st Morning Session: Chair: I. H. Sloan

    9:00 - 10:00 J. D. Ward: Approximation from Spaces of Shifts and of a Positive Definite Kernel

    10:00 - 10:30 P. Binev: Using Three-Scale Equation in Adaptive Refinement

    2nd Morning Session: Chair: W. Haußmann

    11:00 - 11:30 O. Davydov: Bases of Bivariate Piecewise Polynomials

    11:30 - 12:00 G. Nürnberger: Spline Interpolation on Triangulations

    12:00 - 12:30 I. H. Sloan: Uniform Constructive Approximation by Polynomials on the Sphere

    12:30 Closing of the Conference


    Contacting the Editors

    You can contact the editors at the following email addresses:

    Werner Haußmann
    Kurt Jetter
    Manfred Reimer