Image scaling by de la vallée-poussin filtered interpolation

D Occorsio, G Ramella, W Themistoclakis - Journal of Mathematical …, 2023 - Springer
We present a new image scaling method both for downscaling and upscaling, running with
any scale factor or desired size. The resized image is achieved by sampling a bivariate …

Stable discontinuous mapped bases: the gibbs–runge-avoiding stable polynomial approximation (GRASPA) method

S De Marchi, G Elefante, F Marchetti - Computational and Applied …, 2021 - Springer
The mapped bases or Fake Nodes Approach (FNA), introduced in De Marchi et al.(J Comput
Appl Math 364: 112347, 2020c), allows to change the set of nodes without the need of …

On (β, γ)-Chebyshev functions and points of the interval

S De Marchi, G Elefante, F Marchetti - Journal of Approximation Theory, 2021 - Elsevier
In this paper, we introduce the class of (β, γ)-Chebyshev functions and corresponding points,
which can be seen as a family of generalized Chebyshev polynomials and points. For the (β …

[PDF][PDF] Polynomial mapped bases: theory and applications

S De Marchi, G Elefante, E Francomano… - … in Applied and …, 2022 - intapi.sciendo.com
In this paper, we collect the basic theory and the most important applications of a novel
technique that has shown to be suitable for scattered data interpolation, quadrature, bio …

Oversampling errors in multimodal medical imaging are due to the Gibbs effect

D Poggiali, D Cecchin, C Campi, S De Marchi - Mathematics, 2021 - mdpi.com
To analyze multimodal three-dimensional medical images, interpolation is required for
resampling which—unavoidably—introduces an interpolation error. In this work we describe …

[PDF][PDF] Quadrature at fake nodes

S De Marchi, G Elefante… - Dolomites …, 2021 - drna.padovauniversitypress.it
We investigate the use of the so-called mapped bases or fake nodes approach in the
framework of numerical integration. We show that such approach is able to mitigate the …

[HTML][HTML] More properties of (β, γ)-Chebyshev functions and points

S De Marchi, G Elefante, F Marchetti… - Journal of Mathematical …, 2023 - Elsevier
Abstract Recently,(β, γ)-Chebyshev functions, as well as the corresponding zeros, have
been introduced as a generalization of classical Chebyshev polynomials of the first kind and …

[HTML][HTML] Reducing the Gibbs effect in multimodal medical imaging by the Fake Nodes Approach

D Poggiali, D Cecchin, S De Marchi - Journal of Computational …, 2022 - Elsevier
It is a common practice in multimodal medical imaging to undersample the anatomically-
derived segmentation images to measure the mean activity of a co-acquired functional …

[PDF][PDF] (Beta, Gamma)-funzioni di Chebyshev e loro applicazione ai fenomeni di Gibbs e Runge

JZ MARIETHOZ - 2022 - thesis.unipd.it
In questo elaborato presentiamo le (β, γ)-funzioni di Chebyshev ei corrispondenti (β, γ)-punti
di Chebyshev. Mostriamo che possono essere considerati come una generalizzazione dei …

Variably scaled kernels: an overview

M Rossini - Dolomites Research Notes on …, 2022 - drna.padovauniversitypress.it
This paper aims to provide an overview of variably scaled kernels introduced in [10] and
review their applications highlighting the contribution by Stefano De Marchi and his …