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Now showing 1 - 5 of 5
  • Article
    Citation - WoS: 2
    Citation - Scopus: 2
    On the q-bernstein Polynomials of the Logarithmic Function in the Case q > 1
    (Walter de Gruyter Gmbh, 2016) Ostrovska, Sofiya
    The q-Bernstein basis used to construct the q-Bernstein polynomials is an extension of the Bernstein basis related to the q-binomial probability distribution. This distribution plays a profound role in the q-boson operator calculus. In the case q > 1, q-Bernstein basic polynomials on [0, 1] combine the fast increase in magnitude with sign oscillations. This seriously complicates the study of q-Bernstein polynomials in the case of q > 1. The aim of this paper is to present new results related to the q-Bernstein polynomials B-n,B- q of discontinuous functions in the case q > 1. The behavior of polynomials B-n,B- q(f; x) for functions f possessing a logarithmic singularity at 0 has been examined. (C) 2016 Mathematical Institute Slovak Academy of Sciences
  • Article
    Citation - WoS: 7
    On the Approximation of Analytic Functions by the q-bernstein Polynomials in the Case q > 1
    (Kent State University, 2010) Ostrovska, Sofiya
    Since for q > 1, the q-Bernstein polynomials B(n,q) are not positive linear operators on C[0, 1], the investigation of their convergence properties turns out to be much more difficult than that in the case 0 < q < 1. In this paper, new results on the approximation of continuous functions by the q-Bernstein polynomials in the case q > 1 are presented. It is shown that if f is an element of C[0, 1] and admits an analytic continuation f(z) into {z : |z| < a}, then B(n,q) (f; z) -> f (z) as n -> infinity, uniformly on any compact set in {z : |z| < a}.
  • Article
    Citation - WoS: 11
    Citation - Scopus: 13
    The Convergence of q-bernstein Polynomials (0 < q < 1) in the Complex Plane
    (Wiley-v C H verlag Gmbh, 2009) Ostrovska, Sofiya
    The paper focuses at the estimates for the rate of convergence of the q-Bernstein polynomials (0 < q < 1) in the complex plane. In particular, a generalization of previously known results on the possibility of analytic continuation of the limit function and an elaboration of the theorem by Wang and Meng is presented. (C) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
  • Article
    Citation - WoS: 2
    The Approximation of Power Function by the q-bernstein Polynomials in the Case q > 1
    (Element, 2008) Ostrovska, Sofiya
    Since for q > 1. q-Bernstein polynomials are not positive linear operators on C[0, 1] the investigation of their convergence properties turns out to be much more difficult than that in the case 0 < q < 1. It is known that, in the case q > 1. the q-Bernstein polynomials approximate the entire functions and, in particular, polynomials uniformly on any compact set in C. In this paper. the possibility of the approximation for the function (z + a)(alpha), a >= 0. with a non-integer alpha > -1 is studied. It is proved that for a > 0, the function is uniformly approximated on any compact set in {z : vertical bar z vertical bar < a}, while on any Jordan arc in {z : vertical bar z vertical bar > a}. the uniform approximation is impossible, In the case a = 0(1) the results of the paper reveal the following interesting phenomenon: the power function z(alpha), alpha > 0: is approximated by its, q-Bernstein polynomials either on any (when alpha is an element of N) or no (when alpha is not an element of N) Jordan arc in C.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    The Convergence of q-bernstein Polynomials (0 < q < 1) and Limit q-bernstein Operators in Complex Domains
    (Rocky Mt Math Consortium, 2009) Ostrovska, Sofiya; Wang, Heping
    Due to the fact that the convergence properties of q-Bernstein polynomials are not similar to those in the classical case q = 1, their study has become an area of intensive research with a wide scope of open problems and unexpected results. The present paper is focused on the convergence of q-Bernstein polynomials, 0 < q < 1, and related linear operators in complex domains. An analogue of the classical result on the simultaneous approximation is presented. The approximation of analytic functions With the help of the limit q-Bernstein operator is studied.