Zobrazeno 1 - 10
of 23
pro vyhledávání: '"Vitalii V. Arestov"'
Autor:
Vitalii V. Arestov
Publikováno v:
Ural Mathematical Journal, Vol 9, Iss 2 (2023)
We consider a variant \(E_{n,k}(N;r,r;p,p)\) of the four-parameter Stechkin problem \(E_{n,k}(N;r,s;p,q)\) on the best approximation of differentiation operators of order \(k\) on the class of \(n\) times differentiable functions \((0
Externí odkaz:
https://doaj.org/article/a45b52a8e86844979d2ea73f091a0169
Publikováno v:
Ural Mathematical Journal, Vol 8, Iss 2 (2022)
We study the sharp inequality between the uniform norm and \(L^p(0,\pi/2)\)-norm of polynomials in the system \(\mathscr{C}=\{\cos (2k+1)x\}_{k=0}^\infty\) of cosines with odd harmonics. We investigate the limit behavior of the best constant in this
Externí odkaz:
https://doaj.org/article/68dd5e9e4c3841b7848119fe378a1151
Autor:
Vitalii V. Arestov
Publikováno v:
Ural Mathematical Journal, Vol 3, Iss 2 (2017)
We give a characterization of elements of a subspace of a complex Banach space with the property that the norm of a bounded linear functional on the subspace is attained at those elements. In particular, we discuss properties of polynomials that are
Externí odkaz:
https://doaj.org/article/11def3d839af434da2ca6983db81d085
Publikováno v:
Ural Mathematical Journal, Vol 3, Iss 2 (2017)
The paper is devoted to the description of the history and results of the 42nd International S.B.Stechkin's Workshop on function theory, held in August 2017 in the Ilmen Nature Reserve near the town of Miass, Chelyabinsk region.
Externí odkaz:
https://doaj.org/article/7ca99a53c21e4a18b1369fc18c9ae77d
Autor:
Vitalii V. Arestov
Publikováno v:
Ural Mathematical Journal, Vol 1, Iss 1 (2015)
In this paper we give a solution of the problem of the best approximation in the uniform norm of the differentiation operator of order k by bounded linear operators in the class of functions with the property that the Fourier transforms of their deri
Externí odkaz:
https://doaj.org/article/1182411a8a09456e9a3069afbce99b5d
Publikováno v:
Journal of Approximation Theory. 222:40-54
We study the Nikol’skii type inequality for algebraic polynomials on the half-line [ 0 , ∞ ) between the “uniform” norm sup { | f ( x ) | e − x ∕ 2 : x ∈ [ 0 , ∞ ) } and the norm ∫ 0 ∞ | f ( x ) e − x ∕ 2 | q x α d x 1 ∕ q
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::38f2abac9e272b92332260c3adb32ca1
https://doi.org/10.1016/j.jat.2017.05.005
https://doi.org/10.1016/j.jat.2017.05.005
Autor:
Vitalii V. Arestov, M. V. Deikalova
Publikováno v:
Doklady Mathematics. 95:21-25
The sharp inequality of different metrics (Nikol’skii’s inequality) for algebraic polynomials in the interval [−1, 1] between the uniform norm and the norm of the space L (α,β) , 1 ≤ q −1, is investigated. The study uses the generalized t
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::32a3dae0a59023430d286b05204ddf1c
https://doi.org/10.1134/s1064562417010100
https://doi.org/10.1134/s1064562417010100
Autor:
Vitalii V. Arestov
Publikováno v:
Mathematical Optimization Theory and Operations Research ISBN: 9783030226282
MOTOR
MOTOR
Let \(Y^n,\) Open image in new window , be the set of continuous bounded functions on the numerical axis with the following two properties: (1) the Fourier transform of a function is a function of bounded variation on the axis (in particular, a summa
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::3cc6334a77bbb720ddcf11c1aaa57f02
https://doi.org/10.1007/978-3-030-22629-9_30
https://doi.org/10.1007/978-3-030-22629-9_30
Publikováno v:
Computational Methods and Function Theory. 15:689-708
We study the Nikol’skii inequality for algebraic polynomials on the interval \([-1,1]\) between the uniform norm and the norm of the space \(L^{\phi }_q,\)\({1\le q
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::94faec5e3399437fa8e4847783d0258f
https://doi.org/10.1007/s40315-015-0134-y
https://doi.org/10.1007/s40315-015-0134-y
Autor:
Vitalii V. Arestov, Maria Filatova
Publikováno v:
Journal of Approximation Theory. 187:65-81
We solve the problem on the best approximation of the (first-order) differentiation operator by linear bounded operators on the class of twice differentiable functions in the space L 2 ( 0 , ∞ ) . The best approximating operator is constructed. The
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::fb4ed36912b1220710a0058fd8e233a3
https://doi.org/10.1016/j.jat.2014.08.001
https://doi.org/10.1016/j.jat.2014.08.001