English
Related papers

Related papers: On Jackson's theorem for the modulus of smoothness…

200 papers

We prove the theorem converse to Jackson's theorem for a modulus of smoothness of the first order generalised by means of an asymmetric operator of generalised translation.

Functional Analysis · Mathematics 2012-09-10 Muharrem Q. Berisha , Faton M. Berisha

In this paper an asymmetrical operator of generalised translation is introduced, the generalised modulus of smoothness is defined by its means and the direct and inverse theorems in approximation theory are proved for that modulus. ----- V…

Functional Analysis · Mathematics 2012-09-03 Mikhail K. Potapov , Faton M. Berisha

An asymmetric operator of generalised translation is introduced in this paper. Using this operator, we define a generalised modulus of smoothness and prove direct and inverse theorems of approximation theory for it.

Functional Analysis · Mathematics 2012-09-03 Mikhail K. Potapov , Faton M. Berisha

We introduce an asymmetric operator of generalised translation, define the generalised modulus of smoothness by its means, and obtain the direct and inverse theorems in approximation theory for it.

Functional Analysis · Mathematics 2012-08-31 Mikhail K. Potapov , Faton M. Berisha

In this paper, a $k$-th generalized modulus of smoothness is defined based on an asymmetric operator of generalized translation and a theorem is proved about the coincidence of class of functions defined by this modulus and a class of…

Functional Analysis · Mathematics 2012-08-29 Mikhail K. Potapov , Faton M. Berisha

In the present paper, we use a generalised shift operator in order to define a generalised modulus of smoothness. By its means, we define generalised Lipschitz classes of functions, and we give their constructive characteristics.…

Functional Analysis · Mathematics 2014-01-28 Faton M. Berisha , Nimete Sh. Berisha

We give the theorem of coincidence of a class of functions defined by a generalised modulus of smoothness with a class of functions defined by the order of the best approximation by algebraic polynomials. We also prove the appropriate…

Functional Analysis · Mathematics 2012-08-28 Faton M. Berisha

A simple proof is provided to show that any bounded normal operator on a real Hilbert space is orthogonally equivalent to its transpose(adjoint). A structure theorem for invertible skew-symmetric operators, which is analogous to the finite…

Spectral Theory · Mathematics 2020-04-21 B V Rajarama Bhat , Tiju Cherian John

The article $-$ part of a larger thesis which aims to give a detailed description of the generalisation to the category of groups with operators of the classical theory of semisimplicity for modules $-$ presents a straightforward…

Group Theory · Mathematics 2020-12-15 Sebastian Cristian Lesnic

We introduce and study twist vertex operators for a (lower-bounded generalized) twisted modules for a grading-restricted vertex (super)algebra. We prove duality, weak associativity, a Jacobi identity, a generalized commutator formula,…

Quantum Algebra · Mathematics 2019-08-28 Yi-Zhi Huang

In this paper, for a generalised shift operator introduced earlier, we prove theorem of coincidence of classes of functions defined by the order of best approximation by algebraical polynomials and the generalised Lipschitz classes defined…

Classical Analysis and ODEs · Mathematics 2015-11-13 Nimete Sh. Berisha

We study the generalization of shifted Jack polynomials to arbitrary multiplicity free spaces. In a previous paper (math.RT/0006004) we showed that these polynomials are eigenfunctions for commuting difference operators. Our central result…

Representation Theory · Mathematics 2013-10-25 Friedrich Knop

We use a result of Barron, Dong and Mason to give a natural isomorphism between the category of twisted modules and the category of quasi-modules of a certain type for a general vertex operator algebra.

Quantum Algebra · Mathematics 2007-05-23 Haisheng Li

This paper is mainly devoted to studying operator Jensen inequality. More precisely, a new generalization of Jensen inequality and its reverse version for convex (not necessary operator convex) functions have been proved. Several special…

Functional Analysis · Mathematics 2019-06-10 M. Shah Hosseini , H. R. Moradi , B. Moosavi

Generalized smooth functions are a possible formalization of the original historical approach followed by Cauchy, Poisson, Kirchhoff, Helmholtz, Kelvin, Heaviside, and Dirac to deal with generalized functions. They are set-theoretical…

Functional Analysis · Mathematics 2016-06-14 Paolo Giordano , Michael Kunzinger

We introduce appropriate computable moduli of smoothness to characterize the rate of best approximation by multivariate polynomials on a connected and compact $C^2$-domain $\Omega\subset \mathbb{R}^d$. This new modulus of smoothness is…

Classical Analysis and ODEs · Mathematics 2025-04-15 Feng Dai , Andriy Prymak

Generalized translation operators for orthogonal expansions with respect to families of weight functions on the unit ball and on the standard simplex are studied. They are used to define convolution structures and modulus of smoothness for…

Classical Analysis and ODEs · Mathematics 2007-05-23 Yuan Xu

We give uniform proofs of tightness and exponential tightness of the sequences of stationary queue lengths in generalised Jackson networks in a number of setups which concern large, normal and moderate deviations.

Probability · Mathematics 2026-04-09 A. Puhalskii

By extending the classical quantitative approximation results for positive and linear operators in $L^{p}([0, 1]), 1\le p \le +\infty$ of Berens and DeVore in 1978 and of Swetits and Wood in 1983 to the more general case of sublinear,…

Functional Analysis · Mathematics 2022-12-05 Sorin G. Gal , Constantin P. Niculescu

In this paper, we introduce a new semi-discrete modulus of smoothness, which generalizes the definition given by Kolomoitsev and Lomako (KL) in 2023 (in the paper published in the J. Approx. Theory), and we establish very general one- and…

Numerical Analysis · Mathematics 2026-05-28 Danilo Costarelli , Donato Lavella
‹ Prev 1 2 3 10 Next ›