Yanchenko Sergii

Yanchenko Sergii



Publications

    $\hspace{75mm} \normalsize{2024}$

    • Myron I. Grom’yak, Olha Ya. Radchenko and Sergii Ya. Yanchenko. Approximation of functions of many variables from the generalized Nikol’skii–Besov classes in the uniform and integral metrics. J. Math. Sci. 284 (3), 329–344 (2024); Translated from Ukrains’kiĭ Matematychnyĭ Visnyk, Vol. 21, No. 2, pp. 185–204, April–June, 2024.
    https://link.springer.com/article/10.1007/s10958-024-07353-0;


    $\hspace{75mm} \normalsize{2023}$

    • Romanyuk A.S., Yanchenko S.Ya. Estimates for the entropy numbers of the Nikol'skii–Besov classes of functions with mixed smoothness in the space of quasi-continuous functions. Math. Nachr. 2023, Vol. 296 (6), 2575–2587.
    https://onlinelibrary.wiley.com/doi/10.1002/mana.202100202


    $\hspace{75mm} \normalsize{2022}$

    • Romanyuk A.S., Yanchenko S.Ya. Approximation of the classes of periodic functions of one and many variables from the Nikol’skii-Besov and Sobolev spaces. Ukrainian Math. J. 2022, Vol. 74 (6), 967-980; Translated from Ukrains’kyi Matematychnyi Zhurnal 2022, Vol. 74 (6), 844-855.
    https://link.springer.com/article/10.1007/s11253-022-02110-5

    • Romanyuk A.S., Yanchenko S.Ya. Kolmogorov widths of the Nikol'skii-Besov classes of periodic functions of many variables in the space of quasicontinuous functions. Ukr. Math. J. 2022, V. 74, Issue 2, pp. 251–265; Translated from Ukrains’kyi Matematychnyi Zhurnal, V. 74, No. 2, pp. 220–232, February 2022.
    https://link.springer.com/article/10.1007/s11253-022-02061-x

    • Romanyuk A.S., Yanchenko S.Ya. Estimates of approximating characteristics and the properties of the operators of best approximation for the classes of periodic functions in the space $B_{1,1}$. Ukr. Math. J. February 2022, V. 73, Issue 8, pp. 1278–1298; Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 73, No. 8, pp. 1102–1119, August, 2021.
    https://link.springer.com/article/10.1007/s11253-022-01990-x

    $\hspace{75mm} \normalsize{2021}$

    • Yanchenko S.Ya., Radchenko O.Ya. Approximation characteristics of the isotropic Nikol'skii-Besov functional classes. Carpathian Math. Publ. 2021, 13 (3), 851-861.
    https://journals.pnu.edu.ua/index.php/cmp/article/view/5649


    $\hspace{75mm} \normalsize{2020}$

    • Yanchenko S.Ya. Approximation of the Nikol’skii-Besov Functional Classes by Entire Functions of a Special Form. Carpathian Math. Publ. 2020, 12 (1), 148-156.
    https://journals.pnu.edu.ua/index.php/cmp/article/view/3895
    arXiv preprint, arXiv:1912.01087. (in Ukrainian) https://arxiv.org/pdf/1912.01087.pdf


    • Yanchenko S.Ya., Radchenko O.Ya. Approximating Characteristics of the Nikol’skii–Besov Classes $S^{\boldsymbol{r}}_{1,\theta}B(\mathbb{R}^d)$. Ukr. Math. J. April 2020, V. 71, Issue 10, pp. 1608–1626; Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 71, No. 10, pp. 1405–1421, October, 2019.
    https://link.springer.com/article/10.1007/s11253-020-01734-9
    arXiv preprint, arXiv:1607.06069. (in Ukrainian) https://arxiv.org/pdf/1607.06069v1.pdf

    $\hspace{75mm} \normalsize{2018}$

    • Yanchenko S.Ya. Best Approximation of the Functions from Anisotropic Nikol’skii–Besov Classes Defined in $\mathbb{R}^d$. Ukr. Math. J. November 2018, V. 70, Issue 4, pp. 661–670; Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 70, No. 4, pp. 574–582, April, 2018.
    https://link.springer.com/article/10.1007/s11253-018-1523-y
    arXiv preprint arXiv:1703.10699. - 2017. (in Ukrainian) https://arxiv.org/pdf/1703.10699.pdf

    • Yanchenko S.Ya., Stasyuk S.A. Approximative characteristics of functions from the classes $S^{\Omega}_{p,\theta}B$ with a given majorant of mixed moduli of continuity. J. Math. Sci. 235, 103–115 (2018); Translated from Ukrains’kiĭ Matematychnyĭ Visnyk, Vol. 15, No. 1, pp. 132–148, January–March, 2018.
    https://link.springer.com/article/10.1007/s10958-018-4062-z;
    arXiv preprint, arXiv:1611.02313v2. (in Ukrainian) https://arxiv.org/pdf/1611.02313v2.pdf

    • Yanchenko S.Ya. Order estimates of approximation characteristics of functions from the anisotropic Nikol'skii-Besov classes. J. of Math. Sci., 234, No. 1, 98–105 (2018); Translated from Ukrains’kiĭ Matematychnyĭ Visnyk, Vol. 14, No. 4, pp. 595–604, October–December, 2017.
    https://link.springer.com/article/10.1007/s10958-018-3984-9
    arXiv preprint arXiv:arXiv:1709.04650. - 2017. (in Ukrainian) https://arxiv.org/pdf/1709.04650.pdf

    $\hspace{75mm} \normalsize{2017}$

    • Yanchenko S.Ya. Order estimates for the approximative characteristics of functions from the classes $S^{\Omega}_{p,\theta}B$ with a given majorant of generalized mixed modules of smoothness in the uniform metric. Ukr. Math. J. May 2017, V. 68, Issue 12, pp 1975–1985; Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 68, No.12, pp. 1705–1714.
    https://link.springer.com/article/10.1007/s11253-017-1342-6

    $\hspace{75mm} \normalsize{2015}$

    • Stasyuk S.A., Yanchenko S.Ya. Approximation of functions from Nikolskii-Besov type classes of generalized mixed smoothness. Anal. Math. — 2015. — V.41. — P.311—334.
    https://link.springer.com/article/10.1007%2Fs10476-015-0305-0#Abs1

    • Yanchenko S.Ya. Approximation of functions from the isotropic Nikol’skii–Besov classes in the uniform and integral metrics, Ukr. Mat. Zh., 67, No. 10, 1423–1433 (2015); English translation: Ukr. Math. J., 67, No. 10, 1599–1610 (2016).
    https://link.springer.com/article/10.1007/s11253-016-1175-8

    $\hspace{75mm} \normalsize{2014}$

    • Yanchenko S.Ya. Order estimates for approximating characteristics of functions from generalized classes of mixed smoothness of the Nikol’ski–Besov type, in: Collection of Works “Approximation Theory of Functions and Related Problems” [in Ukrainian], Institute of Mathematics, National Academy of Sciences of Ukraine, Kyiv, 11, No. 3 (2014), pp. 330–343. (Paper)

    $\hspace{75mm} \normalsize{2013}$

    • Yanchenko S.Ya. Estimates for approximating characteristics of the classes of functions $S^r_{p,θ}B(\mathbb{R^d})$ in the uniform metric, in: Collection of Works “Approximation Theory of Functions and Related Problems” [in Ukrainian], Institute of Mathematics, National Academy of Sciences of Ukraine, Kyiv, 10, No. 1 (2013), pp. 328–340. (Paper)

    • Myroniuk V.V., Yanchenko S.Ya. Approximation of functions from generalized Nikol’skii–Besov classes by entire functions in Lebesgue spaces, Mat. Stud. 39 (2013), 190–202.
    http://matstud.org.ua/texts/2013/39_2/190-202.html

    • Yanchenko S.Ya. Approximation of functions from the classes $S^r_{p,θ}B$ in the uniform metric. Ukr. Math. J., Vol. 65, Issue 5, 771–779 (November 2013); Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 65, No. 5, pp. 698–705, May, 2013.
    https://link.springer.com/article/10.1007/s11253-013-0813-7

    $\hspace{75mm} \normalsize{2010}$

    • Yanchenko S.Ya. Approximations Besov classes of functions of many variables by entire functions of a special kind. Zb. Pr. Inst. Mat. NAN Ukr. — 2010. — V.7, ¹2. — P.427—434.(in Ukrainian)

    • Yanchenko S.Ya. Approximations of functions with Besov classes by entire function in the space $L_q(\mathbb{R}^d)$. Zb. Pr. Inst. Mat. NAN Ukr. — 2010. — V.7, ¹1. — P.380—391. (in Ukrainian)

    • Yanchenko S.Ya. Approximations of classes $S^{r}_{p,\theta}B(\mathbb{R}^d)$ of functions of many variables by entire functions of a special kind. Ukr. Math. J., V.62, Issue 8, 1307–1325, January 2011; Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 62, No. 8, pp. 1124–1138, August, 2010.
    https://link.springer.com/article/10.1007/s11253-011-0431-1

    • Yanchenko S.Ya. Approximations of classes $B^{\Omega}_{p,\theta}$ of functions of many variables by entire functions in the space $L_q(\mathbb{R}^d)$. Ukr. Math. J., — V.62, Issue 1, P.136—150, August 2010; Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 62, No. 1, pp. 123–135, January, 2010.
    https://link.springer.com/article/10.1007/s11253-010-0338-2

    $\hspace{75mm} \normalsize{2008}$

    • Stasyuk S.A., Yanchenko S.Ya. Best approximations of classes $B^{\Omega}_{p,\theta}$ of functions of many variables in the space$L_p(\mathbb{R}^d)$. In: Theory of Approximation of Functions and Related Problems, Institute of Mathematics, National Academy of Sciences of Ukrainian, Kyiv, 2008, V.5, ¹1, pp. 367–384. (in Ukrainian)
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