References of "Boman, Romain"
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See detailInfluence of thermoelectric coupling on ectopic beats generated by mechano-electric feedback (MEF) in a one-dimensional cardiac fiber model
Collet, Arnaud ULg; Desaive, Thomas ULg; Pierard, Luc ULg et al

in 9th Belgian Day on Biomedical Engineering, Friday November 26th 2010 in the Academy Palace, Hertogstraat 1, 1000 Brussels (2010, November 26)

The influence of thermal processes on electrophysiology has clearly been underlined by Bini et al., using a FitzHugh--Nagumo-type (FHN-type) model. When the temperature is raised, the action potential ... [more ▼]

The influence of thermal processes on electrophysiology has clearly been underlined by Bini et al., using a FitzHugh--Nagumo-type (FHN-type) model. When the temperature is raised, the action potential duration (APD) has been shown to shorten, while the action potential (AP) amplitude decreases, and the conduction velocity increases. In this research, we investigate the effects of thermoelectric coupling on mechano-electric feedback (MEF), and more specifically, on ectopic beats generated by MEF. To investigate these effects, thermoelectric coupling is introduced in a one-dimensional electromechanical model of a cardiac fiber, which considers excitation-contraction coupling (ECC), as well as MEF. [less ▲]

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See detailInfluence of thermoelectric coupling on ectopic beats generated by mechano-electric feedback (MEF) in a one-dimensional cardiac fiber model
Collet, Arnaud ULg; Desaive, Thomas ULg; Pierard, Luc ULg et al

Poster (2010, November 26)

The influence of thermal processes on electrophysiology has clearly been underlined by Bini et al., using a FitzHugh--Nagumo-type (FHN-type) model. When the temperature is raised, the action potential ... [more ▼]

The influence of thermal processes on electrophysiology has clearly been underlined by Bini et al., using a FitzHugh--Nagumo-type (FHN-type) model. When the temperature is raised, the action potential duration (APD) has been shown to shorten, while the action potential (AP) amplitude decreases, and the conduction velocity increases. In this research, we investigate the effects of thermoelectric coupling on mechano-electric feedback (MEF), and more specifically, on ectopic beats generated by MEF. To investigate these effects, thermoelectric coupling is introduced in a one-dimensional electromechanical model of a cardiac fiber, which considers excitation-contraction coupling (ECC), as well as MEF. [less ▲]

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See detailMultiple material mesh generation for biomedical applications
D'Otreppe, Vinciane ULg; Boman, Romain ULg; Ponthot, Jean-Philippe ULg

in Proceedings of the 9th belgian day on biomedical engineering (2010, November 26)

The finite element method is commonly used in biomedical applications for the simulation of the behaviour of biological structures. However, extracting finite element meshes from medical images is still ... [more ▼]

The finite element method is commonly used in biomedical applications for the simulation of the behaviour of biological structures. However, extracting finite element meshes from medical images is still very challenging. We propose an innovative system to create accurate multiple domain tetrahedral meshes from medical images. Our approach is based on an enhanced Marching Tetrahedra algorithm that extracts the boundary surfaces delimiting the different material domains in an integrated manner. Moreover, a surface reconstruction method is employed to ensure that the resulting mesh is a smooth and accurate surface representation of the original sampled structure. Mesh smoothing and decimation algorithms are also revised to conform to the multiple material nature of the system as well as to adhere to the underlying volume data. [less ▲]

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See detailMultiple Material Mesh Generation For Biomedical Applications
D'Otreppe, Vinciane ULg; Boman, Romain ULg; Ponthot, Jean-Philippe ULg

Poster (2010, November 26)

The finite element (FE) method is commonly used in biomedical applications for the simulation of the behaviour of biological structures. A key component in FE simulation is the creation of a finite ... [more ▼]

The finite element (FE) method is commonly used in biomedical applications for the simulation of the behaviour of biological structures. A key component in FE simulation is the creation of a finite element mesh. In medical applications, the meshes should be directly generated from the medical scans. Moreover, biological structures are usually composed of several inner regions that need to be separately segmented, labelled and meshed to be able to apply different material properties in the finite element model. A procedure to create surface meshes from a multi-valued volume data sets is proposed. Following properties are guaranteed: (1) The generated mesh consists of a set of non manifold triangle meshes that separate each connected component in the labelled data set. These interface meshes join each other consistently along their boundaries, i.e., no T junctions nor gaps may appear. (2) The surface mesh is a geometrically accurate representation of the data represented in the medical scans. However, it is not be tainted by the typical aliasing and staircase artifacts that are due to the discrete nature of the voxels. [less ▲]

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See detailEnhanced FEM-based Modeling of Brain Shift Deformation in Image-Guided Neurosurgery
Vigneron, Lara M.; Boman, Romain ULg; Ponthot, Jean-Philippe ULg et al

in Journal of Computational & Applied Mathematics (2010), 234

We consider the problem of improving outcomes for neurosurgery patients by enhancing intraoperative navigation and guidance. Current navigation systems do not accurately account for intraoperative brain ... [more ▼]

We consider the problem of improving outcomes for neurosurgery patients by enhancing intraoperative navigation and guidance. Current navigation systems do not accurately account for intraoperative brain deformation. We focus on the brain shift deformation that occurs just after the opening of the skull and dura. The heart of our system is a nonrigid registration technique using a biomechanical model. We specifically work on two axes: the representation of the structures in the biomechanical model and the evaluation of the surface landmark displacement fields between intraoperative MR images. Using the modified Hausdorff distance as an image similarity measure, we demonstrate that our approach significantly improves the alignment of the intraoperative images. ' 2009 Elsevier B.V. All rights reserved. [less ▲]

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See detailContinuous Roll Forming Simulation Using Arbitrary Lagrangian Eulerian Formalism
Boman, Romain ULg; Ponthot, Jean-Philippe ULg

in Khalili, Nasser; Valliappan, Somasundaram; Li, Qing (Eds.) et al Proceedings of the joint 9th World Congress on Computational Mechanics and 4th Asian Pacific Congress on Computational Mechanics (2010, July)

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See detailDéveloppement d’un formalisme Arbitraire Lagrangien Eulérien tridimensionnel en dynamique implicite. Application aux opérations de mise à forme.
Boman, Romain ULg

Doctoral thesis (2010)

Dans le cadre de la simulation de procédés de mise à forme par la méthode des éléments finis, le formalisme Arbitraire Lagrangien Eulérien (ALE) permet de découpler le mouvement du maillage et de la ... [more ▼]

Dans le cadre de la simulation de procédés de mise à forme par la méthode des éléments finis, le formalisme Arbitraire Lagrangien Eulérien (ALE) permet de découpler le mouvement du maillage et de la matière. Pour de très grandes déformations, la qualité du maillage peut être ainsi améliorée sans avoir recours à une procédure de remaillage complexe et coûteuse. Un second domaine d'application du formalisme ALE est la simulation de procédés stationnaires pour lesquels le maillage peut rester fixe dans la direction de l'écoulement de matière. Ce type de maillage quasi eulérien permet de diminuer le nombre d'éléments finis du modèle numérique par rapport à une simulation lagrangienne classique. En conséquence, le temps de calcul est également réduit. Bien que le formalisme ALE ne soit pas nouveau, il est rarement utilisé en pratique. D'une part, les techniques de repositionnement de noeuds tridimensionnelles ne sont pas évidentes à mettre en oeuvre et, d'autre part, il n'existe pas de schéma de transfert de données précis adapté aux éléments finis à plus d'un point de Gauss tels que ceux utilisés en dynamique implicite. Cette thèse tente de combler ces deux lacunes: une méthode de repositionnement de noeud sur les surfaces libres du solide est présentée. Elle est très robuste et permet de conserver la forme des surfaces malgré le mouvement arbitraire du maillage. Concernant le transfert des données, un schéma de convection 3D précis au second ordre et utilisable pour des éléments finis à plusieurs points de Gauss est déduit d'un opérateur de projection. L'efficacité et la généralité de l'algorithme ALE qui en résulte sont ensuite démontrées sur une série d'applications de plus en plus complexes: impact d'une barre de Taylor, traction d'une barre d'Hopkinson, double extrusion, laminage, planage et profilage à froid. Dans chaque cas, les résultats ALE sont comparés avec des résultats lagrangiens traditionnels ainsi que des mesures expérimentales lorsque celles-ci sont disponibles. [less ▲]

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See detailAdvances in Numerical Simulation of Stationary Processes using Arbitrary Lagrangian Eulerian Formalism. Application to Roll Forming Process.
Boman, Romain ULg; Ponthot, Jean-Philippe ULg

in ECCM 2010, 4th European Conference on Computational Mechanics (2010, May)

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See detailSmooth multiple-region mesh generation for biomedical applications
D'Otreppe, Vinciane ULg; Boman, Romain ULg; Ponthot, Jean-Philippe ULg

in ECCM 2010, 4th European Conference on Computational Mechanics (2010, May)

The finite element method is commonly used in biomedical applications for the simulation of the behaviour of biological structures. However, extracting finite element meshes from medical data is still ... [more ▼]

The finite element method is commonly used in biomedical applications for the simulation of the behaviour of biological structures. However, extracting finite element meshes from medical data is still very challenging. In this article, an innovative system that efficiently reconstructs smooth, multi-material, 3D surface meshes from medical images is presented. Our approach is based on an enhanced Marching Tetrahedra algorithm, which extracts boundary surfaces between different materials within one sweep of the image stack in an integrated manner. Moreover,Multi-Level Partition of Unity implicit models are used to obtain a smooth and accurate surface representation of the original binary sampled surface. Mesh smoothing and decimation algorithms were also revised to adapt to the multi-material nature of the system as well as to adhere to the underlying volume data. [less ▲]

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See detailStationary Roll Forming Simulation using Arbitrary Lagrangian Eulerian Formalism
Boman, Romain ULg; Depauw, Antoine; Hérisson, Damien et al

in Proceedings of International Roll Forming Congress 2009 (2009, October)

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See detailRoll forming of Ultra High Strength Steels: progresses in experimental and modelling knowledge
Depauw, Antoine; Hérisson, Damien; Boman, Romain ULg et al

in Proceedings of International Roll Forming Congress 2009 (2009, October)

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See detailGénération de maillages pour la creation de modèles biomécaniques du cerveau
D'Otreppe, Vinciane ULg; Boman, Romain ULg; Ponthot, Jean-Philippe ULg

in Raous, Michel; Pasquet, Philippe; Rey, Christian (Eds.) Neuvième Colloque National en Calcul des Structures (2009, May)

Nous présentons une méthode efficace et automatique pour générer des maillages éléments finis surfaciques de haute qualité et de bonne fidélité géométrique au départ d’images médicales segmentées. Cette ... [more ▼]

Nous présentons une méthode efficace et automatique pour générer des maillages éléments finis surfaciques de haute qualité et de bonne fidélité géométrique au départ d’images médicales segmentées. Cette méthode est basée sur l’algorithme du Marching Tetrahedra auquel nous avons adjoint des techniques permettant d’ajuster la topologie et les positions nodales du maillage afin de renforcer la qualité des éléments tout en respectant la géométrie de l’objet présent dans les images. Le but ultime de l’approche est la modélisation du cerveau lors d’interventions neurochirurgicales. [less ▲]

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See detailModelling of forming using Metafor – a large strains FE software
Boman, Romain ULg

Scientific conference (2008, November)

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See detailApplication of the Arbitrary Lagrangian Eulerian Formulation to the Numerical Simulation of Forming Process
Boman, Romain ULg; Papeleux, Luc ULg; Ponthot, Jean-Philippe ULg

in Hora, Pavel (Ed.) Numisheet 2008: 7th International Conference and Workshop on Numerical Simulation of 3D Sheet Metal Forming Processes (2008, September)

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See detailIssues in FEM-based Modeling of Brain Shift in Neurosurgery
Vigneron, Lara M.; Boman, Romain ULg; Ponthot, Jean-Philippe ULg et al

in Hogge, Michel; Van Keer, R.; Noels, Ludovic (Eds.) et al Proceedings of ACOMEN’2008, Advanced Computational Methods in Engineering (2008, May)

We consider the problem of improving outcomes for neurosurgery patients by enhancing intraoperative navigation and guidance. Current navigation systems do not accurately account for intraoperative brain ... [more ▼]

We consider the problem of improving outcomes for neurosurgery patients by enhancing intraoperative navigation and guidance. Current navigation systems do not accurately account for intraoperative brain deformation. In this work, we focus on the brain shift deformation that occurs just after the opening of the skull and dura, before any cut and subsequent deformation has happened. We test several algorithms and parameters in order to evaluate their impact on the modeling of the brain shift. [less ▲]

Detailed reference viewed: 49 (13 ULg)