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A Calderon regularized symmetric formulation for the electroencephalography forward problem

John E. Ortiz G., Axelle Pillain, Lyes Rahmouni, Francesco P. Andriulli
2018 Journal of Computational Physics  
The symmetric formulation of the electroencephalography (EEG) forward problem is a well-known and widespread equation thanks to the high level of accuracy that it delivers.  ...  This work addresses and solves this problem by proposing a new regularized symmetric formulation.  ...  A Calderon Preconditioner for the Symmetric Formulation The high accuracy of the symmetric BEM formulation [34] has made of it a very popular tool for solving the EEG forward problem.  ... 
doi:10.1016/ fatcat:3dd6jwmrgncitikpr2k62w5lt4

A New Refinement-Free Preconditioner for the Symmetric Formulation in Electroencephalography [article]

Viviana Giunzioni, John E. Ortiz G., Adrien Merlini, Simon B. Adrian, Francesco P. Andriulli
2022 arXiv   pre-print
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 for complex modelling  ...  The discretization of the new formulation gives rise to a well-conditioned, symmetric, positive-definite system matrix, which can be efficiently solved via fast iterative techniques.  ...  In a similar philosophy, we developed a new preconditioning scheme for the symmetric formulation, which, differently from standard Calderón-based approaches [4] , does not require the evaluation of the  ... 
arXiv:2204.06857v1 fatcat:rfolyrgze5bj3jpb77klbyldqq

Conforming discretizations of boundary element solutions to the electroencephalography forward problem

Lyes Rahmouni, Simon B. Adrian, Kristof Cools, Francesco P. Andriulli
2018 Comptes rendus. Physique  
excellence laboratory, managed by the  ...  Acknowledgements This work was supported in part by the "Agence nationale de la recherche", under Project FASTEEG-ANR-12-JS09-0010, in part by the European Union Project NEUROIMAGEEG, in part by the CominLabs  ...  In this paper, we present a new discretization strategy for the boundary element formulation of the Electroencephalography (EEG) forward problem.  ... 
doi:10.1016/j.crhy.2018.02.002 fatcat:26lpvui3engwvd5nubn3mzbmle

Conforming Discretizations of Boundary Element Solutions of the Electroencephalography Forward Problem [article]

Lyes Rahmouni, Simon Adrian, Kristof Cools, Francesco P. Andriulli
2016 arXiv   pre-print
In this paper we present a new discretization strategy for the boundary element formulation of the Electroencephalography (EEG) forward problem.  ...  This is a particularly limiting problem given that during an high-resolution EEG imaging procedure, several EEG forward problem solutions are required for which the source currents are near or on top of  ...  Methods Standard Integral Equation Formulations of the Electroencephalography Forward Problem Let σ be a smooth, isotropic conductivity distribution and let j be a quasi-static electric volume current  ... 
arXiv:1603.06283v1 fatcat:4qgemtwan5ckxpvzbwbnpefiau

On a Low-Frequency and Contrast Stabilized Full-Wave Volume Integral Equation Solver for Lossy Media [article]

Clément Henry, Adrien Merlini, Lyes Rahmouni, Francesco P. Andriulli
2021 arXiv   pre-print
In this paper we present a new regularized electric flux volume integral equation (D-VIE) for modeling high-contrast conductive dielectric objects in a broad frequency range.  ...  Their scaling by the material permittivity matrix allows for the re-balancing of the equation when applied to inhomogeneous scatterers and thereby makes the proposed method accurate and stable even for  ...  The relative error obtained at each electrode remains below 4 % (Fig. 5) , which confirms the use of the regularized D-VIE to solve the forward problem in EEG source reconstruction.  ... 
arXiv:2108.10690v1 fatcat:k4rfm4sqlzgo5e7ohbclcuyxyy

Numerical Stabilization of the Melt Front for Laser Beam Cutting [chapter]

Torsten Adolph, Willi Schönauer, Markus Niessen, Wolfgang Schulz
2010 Numerical Mathematics and Advanced Applications 2009  
We present computational studies of the given problem.  ...  Numerical experiments will be done for simple linear problems, the Burger's equation, and for the Euler equations with high Mach numbers. 24 This contribution deals with the modeling of soft biological  ...  The situation is more complex for an elasticity problem where a symmetric tensor is required.  ... 
doi:10.1007/978-3-642-11795-4_6 fatcat:nx4nvuxaxfbcdjknopny53ck5e

Proceedings Of The 15Th International Conference On Biomedical Applications Of Electrical Impedance Tomography [article]

Andy Adler, Bartłomiej Grychtol
2015 Zenodo  
This document is the collection of papers accepted for presentation at the 15th International Conference on Biomedical Applications of Electrical Impedance Tomography.  ...  Each individual paper in this collection: (c) 2014 by the indicated authors. Collected work: (c) 2014 Andy Adler and Bartłomiej Grychtol. All rights reserved.  ...  One key advantage is that, once pre-calculations are completed, images can be reconstructed by a single regularized inverse, and it requires little additional time over traditional methods.  ... 
doi:10.5281/zenodo.17749 fatcat:ehd3tnanebhqdoozy6wu27hojm

A comparison of two EIT systems suitable for imaging impedance changes in epilepsy

L Fabrizi, A McEwan, T Oh, E J Woo, D S Holder
2009 Physiological Measurement  
We show the improvement in the reconstruction of a target in a layered medium that is provided by using the layered forward model rather than a homogeneous forward model for simulated data.  ...  A Helmholtz type regularization scheme has been implemented to solve the inverse problem of EIT with the aim to improve detection of small sized object.  ...  Acknowledgments This work is supported in part by CenSSIS, the Center for Subsurface Sensing and Imaging Systems, under the Engineering Research Centers Program of the National Science Foundation (Award  ... 
doi:10.1088/0967-3334/30/6/s07 pmid:19491447 fatcat:nzeetw52ofaslcwhd2kxylvlpu

Decoding Covert Speech From EEG-A Comprehensive Review

Jerrin Thomas Panachakel, Angarai Ganesan Ramakrishnan
2021 Frontiers in Neuroscience  
Speech being the most natural form of communication which human beings acquire even without formal education, imagined speech is an ideal choice of prompt for evoking brain activity patterns for a BCI  ...  This helps a researcher to compare the relative merits and demerits of the different approaches and choose the one that is most optimal.  ...  AUTHOR CONTRIBUTIONS JP drafted the initial version of the manuscript under the guidance of AR. AR wrote the final version of the manuscript.  ... 
doi:10.3389/fnins.2021.642251 pmid:33994922 pmcid:PMC8116487 fatcat:kb355jscljegnc7twcj5a2mcqa

Dynamics of task-related electrophysiological networks: a benchmarking study

Judie Tabbal, Aya Kabbara, Mohamad Khalil, Pascal Benquet, Mahmoud Hassan
2021 NeuroImage  
Tracking these rapid changes is crucial to understand information processing in the brain, but challenging due to the great variety of dimensionality reduction methods used at the network-level and the  ...  We report differences between these methods at the group and subject level.  ...  The authors would also like to thank the the Lebanese University, the Lebanese Association for Scientific Research (LASER) and Campus France, Programme Hubert Curien CEDRE (PROJECT No. 42257YA), for supporting  ... 
doi:10.1016/j.neuroimage.2021.117829 pmid:33549758 fatcat:7zouvg7pobc2vh45ctxxfdkmhu

Concept Design and Dynamic Modelling of a Fibre-Based Continuum Robot for Early Cancer Detection Using DT-TMM [chapter]

Mathias Bærenholdt, Lidai Wang, Xuping Zhang
2018 Mechanisms and Machine Science  
These contributions are provided as a collection of 34 papers that were selected among the 45 submitted contributions on the basis of a blind peer-review process.  ...  We are also grateful to Nathalie Jacobs, Anneke Pot and the staff of Springer for their editorial support.  ...  Acknowledgments The authors wish to acknowledge B. Sinopoli, A. Caseti and G. La Greca for their precious technical support, and D. Battaglia and G.  ... 
doi:10.1007/978-3-030-00329-6_21 fatcat:aln3r456enc3xoac4za6mz7x5i

Talking Sense: The behavioural and neural correlates of sound symbolism

Gwilym Lockwood
2017 Figshare  
also indicate a file drawer problem.  ...  Perhaps the [k] and the [i] feel bright, the forwardmoving tongue while making the [r] sound feels like it represents the light emanating forward from a source, and the large [a] oral cavity represents  ...  a monolingual English speaker, which he spent the rest of his academic career trying to compensate for.  ... 
doi:10.6084/m9.figshare.4872866 fatcat:7snbgww55nal3cisvcvgfi46au

Parkinson Disease, Movement Disorders and Dementia

2012 Basal Ganglia  
This study aims to assess, in a noninterventional epidemiological setting, the incidence and severity of fatigue in PD patients and its correlation with PD severity.  ...  Catania, Catania Introduction: Fatigue is a common non-motor symptom in patients with Parkinson's Disease (PD) and one of the most disabling symptoms of this disease, as reported by patients, with serious  ...  SC108 Formulation of a treatment protocol for OPCA: two cases description P.  ... 
doi:10.1016/j.baga.2012.10.001 fatcat:tgb5tzfxqbeela4ufactz6hqfu

Acute and Chronic Complications

2014 Diabetes  
In addition, the stability data suggests that ZP-GA-1 is suitable for long term storage as a liquid formulation.  ...  Initially, 818 positive blood culture sets were screened for participation in the study.  ...  Hypoglycemia unawareness (HU) is a limiting factor in the treatment of type 1 diabetes (T1D) and is a challenging problem to reverse.  ... 
doi:10.2337/db14-389-664 fatcat:stvrgo2ukrcglba7yjzt3sjfjy

Predictive processing in the retina through evaluation of the omitted-stimulus response

Samantha I. Fradkin
Evaluation of the omitted-stimulus response (OSR), i.e., activity following the omission of a light flash subsequent to a repetitive stimulus, has been examined previously to assess prediction within retinal  ...  Given that little research has focused on the OSR in humans, the present study investigated if predictive processing could be detected at the retinal level within a healthy human sample, and whether this  ...  best explained by a forward connection between V1 and lateral occipital cortex.  ... 
doi:10.7282/t3-7r72-w857 fatcat:z6zovwfyhbbspjc4a3peuhynn4
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