Publikationen 2000 - 2009

Publikationen

  1. (mit D. Leviatan, I.A. Shevchuk, H.-J. Wenz) Interpolatory pointwise estimates for polynomial approximation.
    Constr. Approx. 16 (2000), 603-629.
  2. (mit R.K. Kovacheva) N.I. Achiezer: Das Akademiemitglied S.N. Bernstein und seine Arbeiten zur Konstruktiven Funktionentheorie (Charkov, 1955). Übersetzung aus dem Russischen.
    Mitt. Math. Sem. Giessen 240 (2000) (7+97 pp.).
  3. On the composition and decomposition of positive linear operators.
    In: "Approximation Theory and its Applications" (Proc. Int. Conf. dedicated to the memory of V.K. Dziadyk, Kiev 1999; ed. by O.I. Stepanets', I.O. Shevchuk and V.V. Kovtunets'). Proc. Inst. of Math. of the National Academy of Sciences of Ukraine 31 (2000), 161-180.
  4. Products of parametric extensions: refined estimates.
    In: Proc. 2nd Int. Conf. on "Symmetry and Antisymmetry" in Mathematics, Formal Languages and Computer Science (hrsg. v. G.V. Orman und D. Bocu), 1-15. Brasov: Editura Universitatii "Transilvania" 2000.
  5. (mit L. Beutel und D. Kacsó) Exact and approximate interpolation of 3D-data by bivariate 3D-functions.
    In: "RoGer 2000 - Brasov" (Proc. 4th Romanian-German Sem. Approx. Theory & its Appl., Brasov 2000; hrsg. v. H. Gonska, D. Kacsó and L. Beutel), 47-61. Duisburg: Schriftenreihe des Fachbereichs Mathematik der Gerhard-Mercator-Universität SM-DU-485 (2000).
  6. (mit L. Beutel und D. Kacsó, Hrsg.) "RoGer 2000 - Brasov" (Proc. 4th Romanian-German Sem. Approx. Theory & its Appl., Brasov 2000). Duisburg: Schriftenreihe des Fachbereichs Mathematik der Gerhard-Mercator-Universität SM-DU-485 (2000), 170 pp.
  7. (mit H.B. Knoop) On the 60th birthday of Professor Werner Haußmann.
    Anal. Numér. Théor. Approx. 30, no. 2 (2001), 125-126.
  8. (mit D. Kacsó) Degree of simultaneous approximation by Birkhoff splines.
    Anal. Numér. Théor. Approx. 30, no. 2 (2001), 163-178.
  9. (mit G. Tachev) On the constants in ω2φ-inequalities.
    Rend. Circ. Mat. Palermo (2) Suppl. 68 (2002), 467-477.
  10. (mit L. Beutel, D. Kacsó und G. Tachev) On variation-diminishing Schoenberg operators: new quantitative statements.
    In: Multivariate Approximation and Interpolation with Applications (ed. by M. Gasca), Monogr. Academia Ciencias de Zaragoza 20 (2002), 9-58.
  11. (mit A. Lupaş und L. Lupaş, Hrsg.) "Mathematical Analysis and Approximation Theory" (Proc. 5th Romanian-German Sem. Approx. Theory & its Appl., Sibiu 2002). Sibiu: Burg-Verlag 2002.
  12. (mit Jia-ding Cao) Reflexions on an article of Kumar and Mathur.
    In: "Mathematical Analysis and Approximation Theory" (Proc. 5th Romanian-German Sem. Approx. Theory & its Appl., Sibiu 2002; hrsg. von A. Lupaş, H. Gonska und L. Lupaş), 51-76. Sibiu: Burg-Verlag 2002.
  13. (mit D. Kacsó und G. Tachev) Direct estimates and Bernstein-type inequalities for Schoenberg splines.
    In: "Mathematical Analysis and Approximation Theory" (Proc. 5th Romanian-German Sem. Approx. Theory & its Appl., Sibiu 2002; hrsg. von A. Lupaş, H. Gonska und L. Lupaş), 119-128. Sibiu: Burg-Verlag 2002.
  14. Problems concerning Schoenberg splines.
    In: "Mathematical Analysis and Approximation Theory" (Proc. 5th Romanian-German Sem. Approx. Theory & its Appl., Sibiu 2002; hrsg. von A. Lupaş, H. Gonska und L. Lupaş), 317-324. Sibiu: Burg-Verlag 2002.
  15. (mit L. Beutel, D. Kacsó und G. Tachev) Variation-diminishing splines revisited.
    In: Proc. Int. Sympos. on Numerical Analysis and Approximation Theory (Cluj-Napoca, May 9-11, 2002, dedicated to the 75th Anniversary of Professor Dr. Dimitrie D. Stancu; ed. by Radu T. Trimbitas), 54-75. Cluj-Napoca: Presa Universitară Clujeană 2002.
  16. Positive operators and approximation of functions: selected topics.
    Confer. Sem. Mat. Univ. Bari 288 (2002), 1-28; auch in: Proc. Int. Summer School on Operator Methods for Evolution Equations and Approximation Problems (OMEEAP 2002, Monopoli/Italy, September 2002), 95-122. Rom: Aracne 2003.
  17. (mit G. Tachev) The second Ditzian-Totik modulus revisited: refined estimates for positive linear operators.
    Anal. Numér. Théor. Approx. 32, no. 1 (2003), 39-61.
  18. (mit L. Beutel) Quantitative inheritance properties for simultaneous approximation by tensor product operators.
    Numerical Algorithms 33 (2003), 83-92.
  19. (mit A. Lupaş) On an algorithm for Bernstein polynomials.
    In "Curve and Surface Design: Saint-Malo 2002" (hrsg. von T. Lyche, M.-L. Mazure und L. Schumaker),197-203. Brentwood, TN: Nashboro Press 2003.
  20. (mit I. Gavrea, R. Păltănea, G. Tachev) General estimates for the Ditzian-Totik modulus.
    East Journal on Approximations 9 (2003), 175-194.
  21. (mit L. Beutel) Quantitative inheritance properties for simultaneous approximation by tensor product operators II: applications.
    In: "Mathematics and its Applications" (Proc. 17th Scientific Session; ed. by G.V.Orman), 1-28. Brasov: Editura Universitatii "Transilvania" 2003.
  22. (mit L. Beutel, D. Kacsó und G. Tachev) On the second moments of variation-diminishing splines.
    J. Concr. Appl. Math. 2 (2004), 91-117.
  23. (mit Jia-ding Cao und D. Kacsó) On the impossibility of certain lower estimates for sequences of linear operators.
    Math. Balkanica 19 (2005), 39-58.
  24. (mit L. Beutel, D. Kacsó und G. Tachev) Inverse theorems for Schoenberg splines.
    In: "Mathematical Analysis and Approximation Theory" (Proc. 6th Romanian-German Sem. Approx. Theory & its Appl., Baisoara 2004; hrsg. von M. Ivan & I. Gavrea), 19-24. Cluj-Napoca: Mediamira Science Publisher 2005.
  25. (mit Jia-ding Cao und D. Kacsó) On the second order classical and (weighted) Ditzian-Totik moduli of smoothness.
    In: "Mathematical Analysis and Approximation Theory" (Proc. 6th Romanian-German Sem. Approx. Theory & its Appl., Baisoara 2004; hrsg. von M. Ivan & I. Gavrea), 35-42. Cluj-Napoca: Mediamira Science Publisher 2005.
  26. (mit P. Pițul) Remarks on an article of J.P. King.
    Comment. Math. Univ. Carolinae 46 (2005), 645-652.
  27. (mit D. Kacsó und P. Pițul) The degree of convergence of over-iterated positive linear operators.
    J. of Applied Functional Analysis 1 (2006), 403-423.
  28. (mit I. Raşa) The limiting semigroup of the Bernstein iterates: degree of convergence.
    Acta Math. Hung. 111 (2006), 119-130.
  29. (mit D. Kacsó und P. Pițul) On rational B-spline functions.
    In: "Constructive Theory of Functions - Varna 2005" (ed. by B. Bojanov), 145-157. Sofia: Marin Drinov Academic Publ. House 2006.
  30. (mit P. Pițul und I. Raşa) On Peano's form of the Taylor remainder, Voronovskaja's theorem and the commutator of positive linear operators.
    In: "Numerical Analysis and Approximation Theory" (Proc. Int. Conf. Cluj-Napoca 2006; ed. by O. Agratini & P. Blaga), 55-80. Cluj-Napoca: Casa Cartii de Stiinta 2006.
  31. (mit D. Kacsó, O. Nemitz und P. Pițul) Piecewise linear interpolation revisited: BLaC-wavelets.
    Studia Univ. Babes-Bolyai, Mathematica 51 (2006), no. 4, 105-115.
  32. (mit P. Pițul und I. Raşa) On differences of positive linear operators.
    Carpathian J. Math. 22 (2006), 65-78.
  33. (mit R. Păltănea) Riesz-type representation for positive linear operators preserving continuity.
    Acta Math. Hung. 114 (2007), 153-163.
  34. (mit P. Pițul und I. Raşa) Over-iterates of Bernstein-Stancu operators.
    Calcolo 44 (2007), 117-125.
  35. (mit D. Kacsó und I. Raşa) On genuine Bernstein-Durrmeyer operators.
    Results in Mathematics 50 (2007), 213-225.
  36. On the degree of approximation in Voronovskaja's theorem.
    Studia Univ. Babes-Bolyai, Mathematica 52 (2007), no. 3, 103-116.
  37. (mit Kun-ping Zhu) Eigenvalue constraints for the stability of T-S fuzzy models
    In: "Proc. 2008 American Control Conference", 87-88.
  38. (mit I. Raşa) Remarks on Voronovskaya’s theorem.
    General Mathematics (Sibiu) 16, no. 4 (2008), 87-97.
  39. (mit I. Raşa) Differences of positive linear operators and the second order modulus.
    Carpathian J. Math. 24 (2008), 332-340.
  40. (mit S. Gal, D. Kacsó, R. Păltănea, E. Stănilă und A. Vernescu) Luciana and Alexandru Lupaş: in memoriam.
    Results in Mathematics 53 (2009), 203-215.
  41. (mit A. Acu) Ostrowski inequalities and moduli of smoothness.
    Results in Mathematics 53 (2009), 217-228.
  42. (mit P. Pițul und I. Raşa) General King-type operators.
    Results in Mathematics 53 (2009), 279-286.
  43. (mit G. Tachev) A quantitative variant of Voronovskaja's theorem.
    Results in Mathematics 53 (2009), 287-294.
  44. (mit I. Raşa) Asymptotic behaviour of differentiated Bernstein polynomials.
    Mat. Vesnik 61 (2009), 53-60.
  45. (mit I. Raşa) A Voronovskaya estimate with second order modulus of smoothness.
    In: "Mathematical Inequalities" (Proc. 5th Int. Sympos., Sibiu 2008; ed. by D. Acu et al.), 76-90. Sibiu: Publishing House of "Lucian Blaga" University 2009.
  46. (mit M. Heilmann und I. Raşa) Convergence of iterates of genuine and ultraspherical Durrmeyer operators to the limiting semigroup: C2-estimates.
    J. Approx. Theory 160 (2009), 243–255.