On the rate of strong summability by matrix means in the generalized Hölder metric.
On the strong summability and approximation of Fourier series
One-sided approximation by trigonometric polynomials in -norm, 0
Perron-Frobenius operators and the Klein-Gordon equation
For a smooth curve and a set in the plane , let be the space of finite Borel measures in the plane supported on , absolutely continuous with respect to the arc length and whose Fourier transform vanishes on . Following [12], we say that is a Heisenberg uniqueness pair if . In the context of a hyperbola , the study of Heisenberg uniqueness pairs is the same as looking for uniqueness sets of a collection of solutions to the Klein-Gordon equation. In this work, we mainly address the...
Pointwise strong approximation of almost periodic functions
We consider the class GM(₂β) in pointwise estimate of the deviations in strong mean of almost periodic functions from matrix means of partial sums of their Fourier series.
Positivity of the Cotes Numbers for some Jacobi Abscissas.
Practice of operator relationships in symbolical calculus.
Rationale trigonometrische Tschebyscheff-Approximation in zwei Variablen.
Rationalle Trigonometrische Tschebyscheff-Approximation In Zwei Variablen
Short proofs for the inequalities of Szegö, Markov and Zygmund
Some approximation problems in -spaces of matrix-valued functions
Some orthogonalities in approximation theory.
Some remarks on a theorem of S.M. Lozinski concerning linear process of approximation of periodic functions
Spectral reconstruction of piecewise smooth functions from their discrete data
This paper addresses the recovery of piecewise smooth functions from their discrete data. Reconstruction methods using both pseudo-spectral coefficients and physical space interpolants have been discussed extensively in the literature, and it is clear that an a priori knowledge of the jump discontinuity location is essential for any reconstruction technique to yield spectrally accurate results with high resolution near the discontinuities. Hence detection of the jump discontinuities is critical...
Spectral Reconstruction of Piecewise Smooth Functions from Their Discrete Data
This paper addresses the recovery of piecewise smooth functions from their discrete data. Reconstruction methods using both pseudo-spectral coefficients and physical space interpolants have been discussed extensively in the literature, and it is clear that an a priori knowledge of the jump discontinuity location is essential for any reconstruction technique to yield spectrally accurate results with high resolution near the discontinuities. Hence detection of the jump discontinuities is critical...
Stečkin inequalities for summability methods.
The divergence phenomena of interpolation type operators in space
Theoretical and numerical study of a free boundary problem by boundary integral methods
In this paper we study a free boundary problem appearing in electromagnetism and its numerical approximation by means of boundary integral methods. Once the problem is written in a equivalent integro-differential form, with the arc parametrization of the boundary as unknown, we analyse it in this new setting. Then we consider Galerkin and collocation methods with trigonometric polynomial and spline curves as approximate solutions.
Theoretical and numerical study of a free boundary problem by boundary integral methods
In this paper we study a free boundary problem appearing in electromagnetism and its numerical approximation by means of boundary integral methods. Once the problem is written in a equivalent integro-differential form, with the arc parametrization of the boundary as unknown, we analyse it in this new setting. Then we consider Galerkin and collocation methods with trigonometric polynomial and spline curves as approximate solutions.
Trigonometric approximation by Nörlund type means in -norm
We show that the same degree of approximation as in the theorems proved by L. Leindler [Trigonometric approximation in -norm, J. Math. Anal. Appl. 302 (2005), 129–136] and P. Chandra [Trigonometric approximation of functions in -norm, J. Math. Anal. Appl. 275 (2002), 13–26] is valid for a more general class of lower triangular matrices. We also prove that these theorems are true under weakened assumptions.