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The purpose of this article is to give a Chlodowsky type generalization of Szasz operators defined by means of the Sheffer type polynomials. We obtain convergence properties of our operators with the help of Korovkin's theorem and the order…

Classical Analysis and ODEs · Mathematics 2016-01-06 M. Mursaleen , Khursheed J. Ansari

Let $S_n f$ be the $n$th partial sum of the Fourier series of a function $f$ in $L^1(\D)$, where $\D$ is the ring of integers of a local field $K$. For $1<p<\infty$, we characterize all weight functions $w$ so that the partial sum operators…

Functional Analysis · Mathematics 2021-11-04 Md Nurul Molla , Biswaranjan Behera

We present a streamlined approach for generalized strong and norm convergence of self-adjoint operators in different Hilbert spaces. In particular, we establish convergence of associated (semi-)groups, (essential) spectra and spectral…

Spectral Theory · Mathematics 2026-01-16 Gerald Teschl , Yifei Wang , Bing Xie , Zhe Zhou

Our main purpose of this article is to study the convergence and other related properties of q-Bernstein-Kantorovich operators including the shifted knots of real positive numbers. We design the shifted knots of Bernstein-Kantorovich…

General Mathematics · Mathematics 2022-01-12 Mohammad Ayman Mursaleen , Adem Kilicman , Md. Nasiruzzaman

The convergence of various operator splitting procedures, such as the sequential, the Strang and the weighted splitting, is investigated in the presence of a spatial approximation. To this end a variant of Chernoff's product formula is…

Functional Analysis · Mathematics 2009-06-21 András Bátkai , Petra Csomós , Gregor Nickel

The notion of $\Phi$-like functions is known to be a necessary and sufficient condition for univalence. By applying the idea, we derive several necessary conditions and sufficient conditions for that an analytic function defined on the unit…

Complex Variables · Mathematics 2011-11-29 Ikkei Hotta

In this article we consider the approximation of a variable coefficient (two-sided) fractional diffusion equation (FDE), having unknown $u$. By introducing an intermediate unknown, $q$, the variable coefficient FDE is rewritten as a lower…

Numerical Analysis · Mathematics 2018-10-31 Xiangcheng Zheng , V. J. Ervin , Hong Wang

We define a symmetry map $\varphi$ on a unital $C^\ast$-algebra $\mathcal A$ to be an $\mathbb{R}$-linear map on $\mathcal A$ that generalizes transformations on matrices like: transpose, adjoint, complex-conjugation, conjugation by a…

Operator Algebras · Mathematics 2024-12-31 David Herrera

We study Whitney-type estimates for approximation of convex functions in the uniform norm on various convex multivariate domains while paying a particular attention to the dependence of the involved constants on the dimension and the…

Classical Analysis and ODEs · Mathematics 2025-10-15 Jaskaran Singh Kaire , Andriy Prymak

The purpose of this paper is to study the approximation of vector valued mappings defined on a subset of a normed space. We investigate Korovkin-type conditions under which a given sequence of linear operators becomes a so-called…

Functional Analysis · Mathematics 2007-05-23 Lorenzo D'Ambrosio

The error function occurs widely in multiple areas of mathematics, mathematical physics and natural sciences. There has been no work in this area for the past four decades. In this article, we estimate the coefficient bounds with…

Complex Variables · Mathematics 2016-07-08 S. Kanas , C. Ramachandran , L. Vanitha

We investigate examples of quasi-spectral triples over two-dimensional commutative sphere, which are obtained by modifying the order-one condition. We find equivariant quasi-Dirac operators and prove that they are in a topologically…

Mathematical Physics · Physics 2018-06-04 Andrzej Sitarz

Here we research the univariate quantitative approximation, ordinary and fractional, of Banach space valued continuous functions on a compact interval or all the real line by quasi-interpolation Banach space valued neural network operators.…

Machine Learning · Statistics 2022-02-16 George A Anastassiou

The aim of this paper is to investigate the equivalence conditions for uniform perfectness of quasi-metric spaces. We also obtain the invariant property of uniform perfectness under quasim\"obius maps in quasi-metric spaces. In the end, two…

Complex Variables · Mathematics 2019-03-05 Qingshan Zhou , Yaxiang Li , Ailing Xiao

We consider a class of operator-induced norms, acting as finite-dimensional surrogates to the L2 norm, and study their approximation properties over Hilbert subspaces of L2 . The class includes, as a special case, the usual empirical norm…

Statistics Theory · Mathematics 2011-06-01 Arash A. Amini , Martin J. Wainwright

The objective of this paper is to find an estimation of the essential norm of Riemann-Stieltjes operator from the spaces $F(p,q,s)$ ( general function space) and $H(p,q,\phi)$ (mixed-norm space) into Zygmund-type space in the unit ball of…

Functional Analysis · Mathematics 2024-08-20 M. S. Al Ghafri , M. Hassanlou , Y. Estaremi , Z. Huang

In this paper we study the almost everywhere convergence of the expansions related to the self-adjoint extension of the Laplace-Beltrami operator on the unit sphere. The sufficient conditions for summability is obtained. The more general…

Functional Analysis · Mathematics 2008-07-01 Anvarjon Akhmedov

Roughly speaking, a near-best (abbr. NB) quasi-interpolant (abbr. QI) is an approximation operator of the form $Q_af=\sum_{\alpha\in A} \Lambda_\alpha (f) B_\alpha$ where the $B_\alpha$'s are B-splines and the $\Lambda_\alpha (f)$'s are…

Numerical Analysis · Mathematics 2007-05-23 Paul Sablonniere

We obtain estimates in simultaneous approximation for a summation-integral type genuine hybrid operator. The convergence of derivatives of operator to the corresponding derivatives of the functions is proved and estimates for rate of…

Classical Analysis and ODEs · Mathematics 2026-05-28 Asha Ram Gairola , Nidhi Bisht

We study the manner in which a sequence of spectral shift functions $\xi(\cdot;H_j,H_{0,j})$ associated with abstract pairs of self-adjoint operators $(H_j, H_{0,j})$ in Hilbert spaces $\cH_j$, $j\in\bbN$, converge to a limiting spectral…

Spectral Theory · Mathematics 2011-11-02 Fritz Gesztesy , Roger Nichols