Dr. Nguyen Xuan Ky

Publikációk

  1. Fourier-transzformáció módosított folytonossági modulusairól.
    Mat. Lapok 23 (1972), 99-103
  2. On Jackson and Bernstein type approximation theorem in the case of approximation by albegraic polynomials in LP-space.
    Studia Sci. Math. Hung. 9, (1974), 405-415.
  3. On weighted polynomial approximation with a weight (1-x)alpha (1+x)beta in L2-space.
    Acta Math. Acad. Sci. Hung. 9, (1974), 101-109.
  4. A contribution of the problem of weighted polynomial approximation of the derivative of a function by the derivative of its approximation polynomial.
    Studia Sci. Math. Hung 10 (1974), 309-316.
  5. On derivatives of an algebraic polynomial of best approximation with weight.
    Publications Math. Debrecen, 1977. No 24, 21-23.
  6. On application of duality principle for approximation by spline functions in LP-space.
    Acta Math. Acad. Sci. Hung. 30 (1977), 135-139.
  7. Functional equations and their applications (in vietnamese).
    Egyetemi folyóirat, Hanoi 1977, 1-6.
  8. On Jackson and Bernstein type inequalities (in vietnamese).
    Egyetemi folyóirat, Hanoi 1978, 11-15.
  9. On a Bohr type inequality.
    Acta Math. Hung. 48 (3-4) (1986), 343-346.
  10. A Bohr type inequality on abstract normed linear spaces and its applications for special spaces,
    Acta Szeged, 48 (1985) 261-267.
  11. On approximation by arbitrary system in L2-space.
    Acta Szeged, 49 (1985), 211-219.
  12. (with I. Joó) Answer to a problem of Paul Turán,
    Annales Uni. Sci. Pb. Tomus XXXI. (1988), 229-241.
  13. Riesz közepekkel való approximáció nagyságrendjérõl.
    Mat. Lapok 33 (1986), 47-54.
  14. On simultanous approximation by polynomials.
    (proceedings of Haar memorial conference), II. Eds. J. Szabados, K. Tandori, Coll. Math. Soc. J. Bolyai, 49, Budapest 1987, 661-665.
  15. Súlyozott polynomapproximációról.
    Candidates thesis, Budapest 1976.
  16. (with F. Schipp) On strong summability of polynomial expansions,
    Math. Analysis 12 (1986), 115-127.
  17. On approximation of functions,
    Doctoral thesis, Budapest 1985.
  18. On approximation by algebraic polynomials in weighted spaces.
    Acta Math. Hung., 59 (1-2), 49-58.
  19. On imbedding theorems for weighted polynomial approximation and modulus of continuity of functions.
    Acta Sci. Math. 54 (1990), 313-325.
  20. Necessary and sufficient conditions for imbedding in the theory of best approximation by polynomials.
    Publicationes Math. Debrecen, Tom 40 (1992) Fasc. 1-2, 85-90
  21. On an imbedding theorem.
    Acta Sci. Math. 56 (1992), 115-120.
  22. Some imbedding theorems concerning the moduli of Ditzian and Totik.
    Anal. Math. 19 (1993), 255-265.
  23. On weighted approximation by trigonometric polynomials.
    Studia Sci. Math. Hung. 28 (1993), 183-188.
  24. Weighted Nikolskii type inequalities.
    Studia Sci. Math. Hung. 31 (1996), 375-385.
  25. Relation between Bernstein and Nikolskii inequalities.
    Acta Sci. Math. Hung. 69 (1995), 5-14.
  26. (with Nguyen Quang Hoa) Imbedding theorems in connection with Freud weight.
    Proc. Int. Conf. on Approx. Theory, Kecskemét (Hungary), 1990.
  27. (with Nguyen Quang Hoa) Uljanov-type imbedding theorems in the theory of weighted polynomial approximation.
    Studia Sci. Math. Hung. 29 (1994), 33-43.
  28. A method for characterization of weighted K-functionals.
    Annales Univ. Sci. Budapest Sect. Math. Tomus XXXVIII (1995), 1-5.
  29. Ap-weights in Mechanics.
    Annales Univ Sci.l Budapest, Sect. Comp. 16 (1996) 283-289
  30. Moduli of mean smoothness and approximation with Ap-weight.
    Annales Uni.Sci. Budapest, 40 (97) 37-48.
  31. Rate of convergence in Szegõ’s asymptotic formula for Toeplitz determinants.
    Acta Sci. Math. Hung. 86 (3) (2000), 193-204.
  32. Structure properties of functions and their expansion coefficients in polynomial series.
    East Journal on approximation Vol. 5. No. 3. (1999), 329-346.
  33. Uncertainty relations for orthogonal polynomial and their applications in wavelet analysis.
    East Journal on approximation Vol. 6. No. 4. (2000), 421-446.
  34.  An Alexits’s lemma and its applications in approximation theory.
    Functions, Series, Operators (L. Leindler, F. Schipp, J. Szabados eds.), Budapest 2002, 287-296.
  35. Signal analysis and weighted polynomial approximation, Studia Sci. Math. Hung. 43(2), 159-169 (2oo6).
  36. Sharp inequalities for weighted polynomial approximation , East Journal on Approximations, Vol.12, N..3
              (2oo6), 367-379.