On some properties of LB-splines
On some properties of the Picard operators
We consider the Picard operators and in exponential weighted spaces. We give some elementary and approximation properties of these operators.
On some quadrature rules with Laplace end corrections
We investigate quadrature rules with Laplace end corrections that depend on a parameter β. Specific values of β yield sixth order rules. We apply our results to approximating the sum of slowly converging series s = Σi=1∞ f(i + 1/2) where f ∈ C 6 with its sixth derivative of constant sign on [m, ∞) and ∫ m∞ f(x)dx is known for m ∈ ℕ. Several examples show the efficiency of this method. This paper continues the results from [Solak W., Szydełko Z., Quadrature rules with Gregory-Laplace end corrections,...
On some regular and singular problems of Birkhoff interpolation.
On some shift invariant integral operators, univariate case
In recent papers the authors studied global smoothness preservation by certain univariate and multivariate linear operators over compact domains. Here the domain is ℝ. A very general positive linear integral type operator is introduced through a convolution-like iteration of another general positive linear operator with a scaling type function. For it sufficient conditions are given for shift invariance, preservation of global smoothness, convergence to the unit with rates, shape preserving and...
On Spectral Means And Some Of Their Applications
On spectral properties of the Laplace operator via boundary perturbation.
On ℒ-spline interpolation and approximation on the whole real line
On Spline Systems: Lm-Splines.
On superadditive rates of convergence
On the analogue of the division polynomials for hyperelliptic curves.
On the approximate values of an implicitly given function
On the approximation by compositions of fixed multivariate functions with univariate functions
The approximation in the uniform norm of a continuous function f(x) = f(x₁,...,xₙ) by continuous sums g₁(h₁(x)) + g₂(h₂(x)), where the functions h₁ and h₂ are fixed, is considered. A Chebyshev type criterion for best approximation is established in terms of paths with respect to the functions h₁ and h₂.
On the Approximation by Convolution Operators in Homogeneous Banach Spaces of Periodic Functions
AMS Subject Classification 2010: 41A25, 41A27, 41A35, 41A36, 41A40, 42Al6, 42A85.The paper is concerned with establishing direct estimates for convolution operators on homogeneous Banach spaces of periodic functions by means of appropriately defined Kfunctional. The differential operator in the K-functional is defined by means of strong limit and described explicitly in terms of its Fourier coefficients. The description is simple and independent of the homogeneous Banach space. Saturation of such...
On the approximation of analytic functions by the -Bernstein polynomials in the case .
On the approximation of continuosly diffentialble functions in Hilbert spaces
On the approximation of continuous functions.
On the approximation of functions by matrix means in the generalized Hölder metric
Under some assumptions on the matrix of a summability method, whose rows are sequences of bounded variation, we obtain a generalization and an improvement of some results of Xie-Hua Sun and L. Leindler.
On the approximation of functions on locally compact abelian groups.
On the approximation of locally bounded functions by operators of Bleimann, Butzer and Hahn.