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Now showing 1 - 10 of 15
  • Article
    Citation - WoS: 3
    Citation - Scopus: 4
    New Methods for Approximating Square Roots
    (Elsevier Science inc, 2006) Ozban, Ahmet Yasar
    Some new higher order iterative methods are obtained to approximate the positive square root of a positive real number. Moreover some numerical tests are performed to demonstrate the performances and accuracies of the new methods. The numerical results show that the methods we obtain are competitive with the existing ones. (c) 2005 Published by Elsevier Inc.
  • Article
    Citation - WoS: 22
    Citation - Scopus: 21
    On idempotency and tripotency of linear combinations of two commuting tripotent matrices
    (Elsevier Science inc, 2009) Ozdemir, Halim; Sarduvan, Murat; Ozban, Ahmet Yasar; Guler, Nesrin
    Let T-1 and T-2 be two nonzero commuting n x n tripotent matrices and c(1), c(2) two nonzero complex numbers. Necessary and sufficient conditions for the tripotency and the idempotency of c(1)T(1) + c(2)T(2) are obtained. The problems considered here have also statistical importance when c(1), c(2) are real scalars and T-1, T-2 are real symmetric matrices. (C) 2008 Elsevier Inc. All rights reserved.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 7
    On the q-bernstein Polynomials of Rational Functions With Real Poles
    (Academic Press inc Elsevier Science, 2014) Ostrovska, Sofiya; Ozban, Ahmet Yasar
    The paper aims to investigate the convergence of the q-Bernstein polynomials B-n,B-q(f; x) attached to rational functions in the case q > 1. The problem reduces to that for the partial fractions (x - alpha)(-J), j is an element of N. The already available results deal with cases, where either the pole a is simple or alpha not equal q(-m), m is an element of N-0. Consequently, the present work is focused on the polynomials Bn,q(f; x) for the functions of the form f (x) = (x - q(-m))(-j) with j >= 2. For such functions, it is proved that the interval of convergence of {B-n,B-q(f; x)} depends not only on the location, but also on the multiplicity of the pole - a phenomenon which has not been considered previously. (C) 2013 Elsevier Inc. All rights reserved.
  • Article
    Citation - WoS: 3
    Citation - Scopus: 3
    NEW ALGEBRAIC-TRIGONOMETRIC INEQUALITIES OF LAUB-ILANI TYPE
    (Cambridge Univ Press, 2017) Ozban, Ahmet Yasar
    The Laub-Ilani inequality ['A subtle inequality', Amer. Math. Monthly 97 (1990), 65-67] states that x(x) + y(y) >= x(y) + y(x) for nonnegative real numbers x, y. We introduce and prove new trigonometric and algebraic-trigonometric inequalities of Laub-Ilani type and propose some conjectural algebraictrigonometric inequalities of similar forms.
  • Article
    Citation - WoS: 3
    Citation - Scopus: 3
    The q-bernstein Polynomials of the Cauchy Kernel With a Pole on [0,1] in the Case q > 1
    (Elsevier Science inc, 2013) Ostrovska, Sofiya; Ozban, Ahmet Yasar
    The problem to describe the Bernstein polynomials of unbounded functions goes back to Lorentz. The aim of this paper is to investigate the convergence properties of the q-Bernstein polynomials B-n,B-q(f; x) of the Cauchy kernel 1/x-alpha with a pole alpha is an element of [0, 1] for q > 1. The previously obtained results allow one to describe these properties when a pole is different from q(-m) for some m is an element of {0, 1, 2, ...}. In this context, the focus of the paper is on the behavior of polynomials B-n,B-q(f; x) for the functions of the form f(m)(x) = 1/(x - q(-m)), x not equal q(-m) and f(m)(q(-m)) = a, a is an element of R. Here, the problem is examined both theoretically and numerically in detail. (C) 2013 Elsevier Inc. All rights reserved.
  • Article
    Citation - WoS: 7
    Citation - Scopus: 7
    On the q-bernstein Polynomials of Unbounded Functions With q > 1
    (Hindawi Ltd, 2013) Ostrovska, Sofiya; Ozban, Ahmet Yasar
    The aim of this paper is to present new results related to the q-Bernstein polynomials B-n,B-q (f;x) of unbounded functions in the case q > 1 and to illustrate those results using numerical examples. As a model, the behavior of polynomials B-n,B-q (f;x) is examined both theoretically and numerically in detail for functions on [0, 1] satisfying f(x) similar to Kx(-alpha) as x -> 0(+), where alpha > 0 and K not equal 0 are real numbers.
  • Article
    On the Convergence of the q-bernstein Polynomials for Power Functions
    (Springer Basel Ag, 2021) Ostrovska, Sofiya; Ozban, Ahmet Yasar
    The aim of this paper is to present new results related to the convergence of the sequence of the complex q-Bernstein polynomials {B-n,B-q(f(alpha); z)}, where 0 < q not equal 1 and f(alpha) = x(alpha), alpha >= 0, is a power function on [0, 1]. This study makes it possible to describe all feasible sets of convergence K for such polynomials. Specifically, if either 0 < q < 1 or alpha is an element of N-0, then K = C, otherwise K = {0} boolean OR {q(-j)}(j=0)(infinity). In the latter case, this identifies the sequence K = {0} boolean OR {q(-j)}(j=0)(infinity) as the 'minimal' set of convergence for polynomials B-n,B-q(f; z), f is an element of C[0, 1] in the case q > 1. In addition, the asymptotic behavior of the polynomials {B-n,B-q(f(alpha); z)}, with q > 1 has been investigated and the obtained results are illustrated by numerical examples.
  • Article
    Polynomial Logistic Distribution Associated With a Cubic Polynomial
    (Taylor & Francis inc, 2017) Aksoy, Umit; Ostrovska, Sofiya; Ozban, Ahmet Yasar
    Let P(x) be a polynomial monotone increasing on ( - , +). The probability distribution possessing the distribution function is called the polynomial logistic distribution with associated polynomial P. This has recently been introduced by Koutras etal., who have also demonstrated its importance for modeling financial data. In this article, the properties of the polynomial logistic distribution with an associated polynomial of degree 3 have been investigated in detail. An example of polynomial logistic distribution describing daily exchange rate fluctuations for the US dollar versus the Turkish lira is provided.
  • Article
    Citation - WoS: 47
    Citation - Scopus: 68
    On the Positive Solutions of the System of Rational Difference Equations
    (Academic Press inc Elsevier Science, 2006) Ozban, Ahmet Yasar
    Our aim in this paper is to investigate the periodic nature of solutions of the system of rational difference equations x(n+1) = 1/y(n-k), y(n+1) = yn/x(n-mYn-m-k), n = 0, 1,..., where k is a nonnegative integer, m is a positive integer and the initial values x(-m), x(-m+1),..., x(0), y(-m-k), y(-m-k+1),..., y(0) are positive real numbers. (c) 2005 Elsevier Inc. All rights reserved.
  • Article
    Citation - WoS: 45
    Citation - Scopus: 61
    On the System of Rational Difference Equations xn = a yn< = byn-3<
    (Elsevier Science inc, 2007) Ozban, Ahmet Yasar
    In this paper we investigate the behaviour of the positive solutions of the system of rational difference equation x(n) = a/y(n-3), y(n) = by(n-3)/x(n-q)Y(n-q), n = 1, 2,..., where q > 3 is a positive integer with 3 inverted iota q, a and b are positive constants and tile initial values x(-q+1),x(-q+2),...,x0, Y-q+1,y(-q+2),...,y(0) are positive real numbers. (C) 2006 Elsevier Inc. All rights reserved.