Publications associées à Singular integral

Publications associées (16)

A Note on BIBO Stability

The statements on the BIBO stability of continuoustime convolution systems found in engineering textbooks are often either too vague (because of lack of hypotheses) or mathematically incorrect. What is more troubling is that they usually exclude the identi ...

2020

Survey on the Figà–Talamanca Herz algebra

Antoine Derighetti

This paper presents a self contained approach to the theory of convolution operators on locally compact groups (both commutative and non commutative) based on the use of the Figà–Talamanca Herz algebras. The case of finite groups is also considered. ...

2019

A Fourier-accelerated volume integral method for elastoplastic contact

Jean-François Molinari, Guillaume Anciaux, Lucas Henri Galilée Frérot

The contact of solids with rough surfaces plays a fundamental role in physical phenomena such as friction, wear, sealing, and thermal transfer. However, its simulation is a challenging problem due to surface asperities covering a wide range of length-scale ...

2019

Harmonic Singular Integrals and Steerable Wavelets in $ L _{ 2 } $ $ (\mathbb{R} ^{ d } $ )

Michaël Unser, John Paul Ward

Here we present a method of constructing steerable wavelet frames in

L _{ 2 }

(\mathbb{R} ^{ d }

) that generalizes and unifies previous approaches, including Simoncelli's pyramid and Riesz wavelets. The motivation for steerable wavelets is the nee ...

Elsevier2014

Learning with tensors: a framework based on convex optimization and spectral regularization

Quoc Tran Dinh

We present a framework based on convex optimization and spectral regularization to perform learning when feature observations are multidimensional arrays (tensors). We give a mathematical characterization of spectral penalties for tensors and analyze a uni ...

Springer2014

Fast and accurate computation of hyper-singular integrals in Galerkin surface integral equation formulations via the direct evaluation method

Juan Ramon Mosig, Athanasios Polymeridis

Hypersingular 4-D integrals, arising in the Galerkin discretization of surface integral equation formulations, are computed by means of the direct evaluation method. The proposed scheme extends the basic idea of the singularity cancellation methods, usuall ...

Institute of Electrical and Electronics Engineers2011

On the analytic-numeric treatment of weakly singular integrals on arbitrary polygonal domains

Juan Ramon Mosig, Athanasios Polymeridis, Sergio Lopez Pena

An alternative analytical approach to calculate the weakly singular free-space static potential integral associated to uniform sources is presented. Arbitrary oriented flat polygons are considered as integration domains. The technique stands out by its mat ...

The Electromagnetic Academy2011

Gravitational Lensing Accuracy Testing 2010 (Great10) Challenge Handbook

Frédéric Courbin, Anaïs Marie Rassat, Matthias Bethge, Marc Gentile, Guldariya Nurbaeva

GRavitational lEnsing Accuracy Testing 2010 (GREAT10) is a public image analysis challenge aimed at the development of algorithms to analyze astronomical images. Specifically, the challenge is to measure varying image distortions in the presence of a varia ...

2011

Evaluating the singular integrals arising in MPIE formulations with a double-exponential algorithm

Juan Ramon Mosig, Athanasios Polymeridis

Novel generalized Cartesian product rules for the computation of weakly singular integrals, arising in the mixed potential integral equation formulations are presented in this paper. The key feature of the proposed integration schemes lies in the incorpora ...

Ieee Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2010

Wavelet Steerability and the Higher-Order Riesz Transform

Michaël Unser, Dimitri Nestor Alice Van De Ville

Our main goal in this paper is to set the foundations of a general continuous-domain framework for designing steerable, reversible signal transformations (a.k.a. frames) in multiple dimensions (d ≥ 2). To that end, we introduce a self-reversible, Nth-order ...

Institute of Electrical and Electronics Engineers2010

A property of Bp(G). Applications to convolution operators

Antoine Derighetti

A new property of B-p(G), permits to obtain an approximation theorem for p-convolution operators and a non-commutative version of the Lohoues monomorphism theorem concerning the norm closure of the set of all p-convolution operators with compact support. ( ...

2009

An Extension Property For The Figa-Talamanca Herz Algebra

Christian Fiorillo

Let G be a locally compact group and H a closed amenable subgroup of G. We prove that every element in A(p)(H) with compact support can be extended to an element of A(p)(G) of which we control the norm and support. The result is new even for the Fourier al ...

American Mathematical Society (AMS)2009

Higher-Order Riesz Transforms And Steerable Wavelet Frames

Michaël Unser, Dimitri Nestor Alice Van De Ville

We introduce an Nth-order extension of the Riesz transform in d dimensions. We prove that this generalized transform has the following remarkable properties: shift-invariance, scale-invariance, inner-product preservation, and steerability. The pleasing con ...

Ieee Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2009

Convolution Operators And Homomorphisms Of Locally Compact Groups

Let 1 < p < infinity, let G and H be locally compact groups and let c) be a continuous homomorphism of G into H. We prove, if G is amenable, the existence of a linear contraction of the Banach algebra CVp (G) of the p-convolution operators on G into CVp (H ...

Cambridge University Press2008

Cardinal Exponential Splines: Part II—Think Analog, Act Digital

Michaël Unser

By interpreting the Green-function reproduction property of exponential splines in signal processing terms, we uncover a fundamental relation that connects the impulse responses of allpole analog filters to their discrete counterparts. The link is that the ...

IEEE2005

Electromagnetic analysis of 2.5D structures in open layered media

This thesis presents a specialization of the integral equation (IE) method for the analysis of three-dimensional metallic and dielectric structures embedded in laterally unbounded (open) layered media. The method remains basically spatial but makes use of ...

EPFL2005