Results 1 to 10 of about 592 (167)

Two sharp inequalities for operators in a Hilbert space

Researches in Mathematics, 2022
In this paper we obtained generalisations of the L. V. Taikov’s and N. Ainulloev’s sharp inequalities, which estimate a norm of function's first-order derivative (L. V. Taikov) and a norm of function's second-order derivative (N.
N.O. Kriachko
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On the nonsymmetric approximation of continuous functions in the integral metric

Researches in Mathematics, 2020
In the paper, an exact estimate of the best nonsymmetric approximation in the integral metric by the constants of continuous functions that belong to the classes $H^\omega[a,b]$ is proved.
V.F. Babenko, O.V. Polyakov
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Coefficients of multiple Fourier-Haar series and variational modulus of continuity

Қарағанды университетінің хабаршысы. Математика сериясы, 2023
In this paper, we introduce the concept of a variational modulus of continuity for functions of several variables, give an estimate for the sum of the coefficients of a multiple Fourier-Haar series in terms of the variational modulus of continuity, and ...
T.B. Akhazhanov, N.А. Bokayev, D.T. Matin, T. Aktosun   +3 more
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Approximation on a class of Phillips operators generated by q-analogue

Journal of Inequalities and Applications, 2020
The main purpose of this article is to introduce a new generalization of q-Phillips operators generated by Dunkl exponential function. We establish some approximation results for these operators. We also determine the order of approximation, and the rate
Abdullah Alotaibi
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Approximation by bivariate Chlodowsky type Szász–Durrmeyer operators and associated GBS operators on weighted spaces

Journal of Inequalities and Applications, 2022
In this article, we consider a bivariate Chlodowsky type Szász–Durrmeyer operators on weighted spaces. We obtain the rate of approximation in connection with the partial and complete modulus of continuity and also for the elements of the Lipschitz type ...
Reşat Aslan, M. Mursaleen
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Parametric Extension of a Certain Family of Summation-Integral Type Operators

Cumhuriyet Science Journal, 2023
In this paper, we introduce a parametric extension of a certain family of summation-integral type operators on the interval [0,∞). Firstly, we obtain test functions and central moments. Secondly, we investigate weighted approximation properties for these
İsmet Yüksel, Nadire Fulda Odabaşı
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On the Approximation of Periodic Functions in L2 and the Values of the Widths of Certain Classes of Functions

Моделирование и анализ информационных систем, 2015
The sharp Jackson–Stechkin inequalities are received, in which a special module of continuity Ωem(f;t) determined by Steklov’s function is used instead the usual modulus of continuity of mth order ωm(f;t).
K. Tukhliev
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Approximate properties of Abel-Poisson integrals on classes of differentiable functions defined by moduli of continuity

Karpatsʹkì Matematičnì Publìkacìï, 2023
The paper deals with the problem of approximation in the uniform metric of $W^{1}H_{\omega}$ classes using one of the classical linear summation methods for Fourier series given by a set of functions of a natural argument, namely, using the Abel-Poisson ...
Yu.I. Kharkevych, T.A. Stepaniuk
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A new kind of Bernstein-Schurer-Stancu-Kantorovich-type operators based on q-integers

Journal of Inequalities and Applications, 2017
Agrawal et al. (Boll. Unione Mat. Ital. 8:169-180, 2015) introduced a Stancu-type Kantorovich modification of the operators proposed by Ren and Zeng (Bull. Korean Math. Soc.
Ruchi Chauhan, Nurhayat Ispir, PN Agrawal   +2 more
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On functions of van der Waerden type [PDF]

Известия Саратовского университета. Новая серия: Математика. Механика. Информатика, 2023
Let $\omega(t)$ be an arbitrary modulus of continuity type function, such that $\omega(t)/t\to+\infty$, as $t\to+0$. We construct a continuous nowhere-differentiable function $V_\omega(x)$, $x\in[0;1]$, that satisfies the following conditions: 1)  ...
Rubinstein, Aleksandr I., Telyakovskii, Dmitrii S.   +1 more
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