15 citations · 31 across the 30 of their papers we have counts for
34 papers
Volume-Surface-Wire Integral Equations for EEG Source Imaging
Paolo Ricci, Maxime Monin, Alessandro Mascherin +2
In EEG source imaging, the precision of the imaging of the brain activity depends on the accuracy of the forward head model which is, in turn, affected by the representation of tis…
Spectral Filtering of 3D Integral Operators Using Modified Green's Functions
Alessandro Bellusci, Viviana Giunzioni, Adrien Merlini +1
Several recent contributions have analyzed and illustrated the effectiveness of operator filtering, both in terms of regularization and compression, when handling dense matrices ar…
A Numerical Approach to Operator Filtering within the Adaptive Integral Method for Electromagnetic Integral Equations
Tommaso Pignatelli, Viviana Giunzioni, Paolo Ricci +3
Operator filtering allows for the regularization and compression of dense integral operators, effectively mitigating the memory and computational costs associated with iterative so…
High-Frequency Preconditioners for Electromagnetic Integral Equations Based on Helmholtz Regularizations
S. Ciciriello, V. Giunzioni, A. Dély +3
The numerical solution of the Electric Field Integral Equation (EFIE) via the Boundary Element Method (BEM) can be computationally challenging due to conditioning issues arising in…
Asymptotic Spectral Insights Behind Fast Direct Solvers for High-Frequency Electromagnetic Integral Equations on Non-Canonical Geometries
V. Giunzioni, C. Henry, A. Merlini +1
Integral-equation-based fast direct solvers for electromagnetic scattering can substantially reduce computational costs, especially in the presence of multiple excitations. We rece…
Majorization-Minimization Networks for Inverse Problems: An Application to EEG Imaging
Le Minh Triet Tran, Sarah Reynaud, Ronan Fablet +3
Inverse problems are often ill-posed and require optimization schemes with strong stability and convergence guarantees. While learning-based approaches such as deep unrolling and m…
A High-Order Discretization Scheme for Surface Integral Equations for Analyzing the Electroencephalography Forward Problem
Rui Chen, Viviana Giunzioni, Adrien Merlini +1
A Nystrom-based high-order (HO) discretization scheme for surface integral equations (SIEs) for analyzing the electroencephalography (EEG) forward problem is proposed in this work.…
Spectral Analysis of Discretized Boundary Integral Operators in 3D: a High-Frequency Perspective
V. Giunzioni, A. Merlini, F. P. Andriulli
When modeling propagation and scattering phenomena using integral equations discretized by the boundary element method, it is common practice to approximate the boundary of the sca…
Limitations of Nyquist Criteria in the Discretization of 2D Electromagnetic Integral Equations at High Frequency: Spectral Insights into Pollution Effects
Viviana Giunzioni, Adrien Merlini, Francesco P. Andriulli
The use of boundary integral equations in modeling boundary value problems-such as elastic, acoustic, or electromagnetic ones-is well established in the literature and widespread i…
Low-Frequency Stabilizations of the PMCHWT Equation for Dielectric and Conductive Media: On a Full-Wave Alternative to Eddy-Current Solvers
V. Giunzioni, A. Scazzola, A. Merlini +1
We propose here a novel stabilization strategy for the PMCHWT equation that cures its frequency and conductivity related instabilities and is obtained by leveraging quasi-Helmholtz…
On a High-Frequency Analysis of Some Relevant Integral Equations in Electromagnetics
V. Giunzioni, A. Merlini, F. P. Andriulli
In this contribution we analyze the spectral properties of some commonly used boundary integral operators in computational electromagnetics and of their discrete counterparts, high…
On the Computation of Square Roots and Inverse Square Roots of Gram Matrices for Surface Integral Equations in Electromagnetics
Rui Chen, Adrien Merlini, Francesco P. Andriulli
Surface integral equations (SIEs)-based boundary element methods are widely used for analyzing electromagnetic scattering scenarii. However, after discretization of SIEs, the spect…
Calderón Strategies for the Convolution Quadrature Time Domain Electric Field Integral Equation
Pierrick Cordel, Alexandre Dély, Adrien Merlini +1
In this work, we introduce new integral formulations based on the convolution quadrature method for the time-domain modeling of perfectly electrically conducting scatterers that ov…
Linear-in-Complexity Computational Strategies for Modeling and Dosimetry at TeraHertz
Viviana Giunzioni, Giuseppe Ciacco, Clément Henry +2
This work presents a fast direct solver strategy allowing full-wave modeling and dosimetry at terahertz (THz) frequencies. The novel scheme leverages a preconditioned combined fiel…
High-order quasi-Helmholtz Projectors: Definition, Analyses, Algorithms
Johann Bourhis, Adrien Merlini, Francesco P. Andriulli
The accuracy of the electric field integral equation (EFIE) can be substantially improved using high-order discretizations. However, this equation suffers from ill-conditioning and…
On some Operator Filtering Strategies Based on Suitably Modified Green's Functions
Matteo E. Masciocchi, Ermanno Citraro, Alexandre Dély +3
Recent contributions showed the benefits of operator filtering for both preconditioning and fast solution strategies. While previous contributions leveraged laplacian-based filters…
Laplacian Filtered Loop-Star Decompositions and Quasi-Helmholtz Laplacian Filters: Definitions, Analysis, and Efficient Algorithms
Adrien Merlini, Clément Henry, Davide Consoli +3
Quasi-Helmholtz decompositions are fundamental tools in integral equation modeling of electromagnetic problems because of their ability of rescaling solenoidal and non-solenoidal c…
On a Calderón preconditioner for the symmetric formulation of the electroencephalography forward problem without barycentric refinements
Viviana Giunzioni, John E. Ortiz G., Adrien Merlini +2
We present a Calderón preconditioning scheme for the symmetric formulation of the forward electroencephalographic (EEG) problem that cures both the dense discretization and the hig…
Fast Direct Solvers for Integral Equations at Low-Frequency Based on Operator Filtering
Clément Henry, Davide Consoli, Alexandre Dély +3
This paper focuses on fast direct solvers for integral equations in the low-to-moderate-frequency regime obtained by leveraging preconditioned first kind or second kind operators r…
Stabilized Single Current Inverse Source Formulations Based on Steklov-Poincaré Mappings
Paolo Ricci, Ermanno Citraro, Adrien Merlini +1
The inverse source problem in electromagnetics has proved quite relevant for a large class of applications. In antenna diagnostics in particular, Love solutions are often sought at…
On a Constrained Pseudoinverse for the Electromagnetic Inverse Source Problem
Ermanno Citraro, Alexandre Dély, Adrien Merlini +1
Inverse source approaches have shown their relevance for several applications in the past years. They rely on the solution of an ill-posed problem where near-field/current data is…
Brain-Computer Interfaces: Investigating the Transition from Visually Evoked to Purely Imagined Steady-State Potentials
Arturo Micheli, Davide Consoli, Adrien Merlini +2
Brain-Computer Interfaces (BCIs) based on Steady State Visually Evoked Potentials (SSVEPs) have proven effective and provide significant accuracy and information-transfer rates. Th…
A New Refinement-Free Preconditioner for the Symmetric Formulation in Electroencephalography
Viviana Giunzioni, John E. Ortiz G., Adrien Merlini +2
Widely employed for the accurate solution of the electroencephalography forward problem, the symmetric formulation gives rise to a first kind, ill-conditioned operator ill-suited f…
On the Fast Direct Solution of a Preconditioned Electromagnetic Integral Equation
Davide Consoli, Clément Henry, Alexandre Dély +6
This work presents a fast direct solver strategy for electromagnetic integral equations in the high-frequency regime. The new scheme relies on a suitably preconditioned combined fi…