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See detailEmbedded solids of any dimension in the X-FEM defined on higher-order approximations
Duboeuf, Frédéric ULiege; Béchet, Eric ULiege

Conference (2016, June 06)

Embedded interface methods bring a significant simplification of the modelling process before analysis. Complex geometries and moving boundaries may be described with great flexibility, reducing the ... [more ▼]

Embedded interface methods bring a significant simplification of the modelling process before analysis. Complex geometries and moving boundaries may be described with great flexibility, reducing the meshing step to that of a simple bounding box. Following this idea – to dissociate the field approximation from the geometric description – manifolds of different dimensions may be embedded in the same bulk mesh. However, special attention should be given to the difference of dimensions between that of problem domain and that of bulk mesh (the codimension). Whereas the direct use of the shape functions of the bulk mesh is possible for a problem domain of codimension zero, this approach is no longer possible in other configurations, for instance a beam in a 3D mesh. Unlike approaches introducing independent overlapping meshes for each subdomain, function spaces may be built from the traces of higher dimensional spaces built upon the bulk mesh. For closed curves in 2D and closed surfaces in 3D, the resulting discrete method based on P1 FE have already been studied in the literature. To avoid badly conditioned linear systems, specific treatments are required, e.g. preconditioning approaches or stabilization techniques. Here, we propose to deplete wisely the trace space. We investigate higher-order function spaces to solve the diffusion equation in embedded solids of any codimension. A new space-reducer algorithm is introduced to design the dedicated spaces that avoids ill-conditionning while treating boundary conditions. We present the results of several numerical experiments with convergence analyses. To conclude, applications of this technique to embedded beams or shells is discussed. [less ▲]

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See detailEmbedded solids of any dimension in the X-FEM. Part I - Building a dedicated P1 function space
Duboeuf, Frédéric ULiege; Béchet, Eric ULiege

in Finite Elements in Analysis and Design (2017)

This paper focuses on the design of a dedicated P1 function space to model elliptic boundary value problem on a manifold embedded in a space of higher dimension. Using the traces of the linear P1 shape ... [more ▼]

This paper focuses on the design of a dedicated P1 function space to model elliptic boundary value problem on a manifold embedded in a space of higher dimension. Using the traces of the linear P1 shape functions, it introduces an algorithm to reduce the function space into an equivalent space having the same properties than a P1 Lagrange approximation. Convergence studies involving problems of codimension one or two embedded in 2D or 3D show good accuracy with regard to classical finite element and analytical solutions. The effects of the relative position of the domain with respect to the mesh are studied in a sensitivity analysis; it illustrates how the proposed solution allows to keep the condition number bounded. A comparative study is performed with the method introduced by Olshanskii et al. 2009 on a closed surface to validate our approach. The robustness of the proposed approach is investigated with regard to their method and that of Burman et al. 2016. This paper is the first in a series of two, on the topic of embedded solids of any dimension within the context of the extended finite element method. It investigates problems involving borderless domains or domains with boundary subject to Dirichlet constraint defined only on the boundaries of the bulk mesh, while the forthcoming paper overcomes this limitation by introducing a new stable Lagrange multiplier space for Dirichlet boundary condition (and more generally stiff condition), that is valid for every combination of the background mesh and manifold dimensions. The combination of both algorithms allows to handle any embedding i.e. 1D, 2D and 3D problems embedded in 2D or 3D background meshes. [less ▲]

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See detailEmbedded solids of any dimension in the X-FEM. Part II - Imposing Dirichlet boundary conditions
Duboeuf, Frédéric ULiege; Béchet, Eric ULiege

in Finite Elements in Analysis and Design (2017)

This paper focuses on the design of a stable Lagrange multiplier space dedicated to enforce Dirichlet boundary conditions on embedded boundaries of any dimension. It follows a previous paper in a series ... [more ▼]

This paper focuses on the design of a stable Lagrange multiplier space dedicated to enforce Dirichlet boundary conditions on embedded boundaries of any dimension. It follows a previous paper in a series of two, on the topic of embedded solids of any dimension within the context of the extended finite element method. While the first paper is devoted to the design of a dedicated P1 function space to solve elliptic equations defined on manifolds of codimension one or two (curves in 2D and surfaces in 3D, or curves in 3D), the general treatment of Dirichlet boundary conditions, in such a setting, remains to be addressed. This is the aim of this second paper. A new algorithm is introduced to build a stable Lagrange multiplier space from the traces of the shape functions defined on the background mesh. It is general enough to cover: (i) boundary value problems investigated in the first paper (with, for instance, Dirichlet boundary conditions defined along a line in a 3D mismatching mesh); but also (ii) those posed on manifolds of codimension zero (a domain embedded in a mesh of the same dimension) and already considered in Béchet et al. 2009. In both cases, the compatibility between the Lagrange multiplier space and that of the bulk approximation (the dedicated P1 function space used in (i), or classical shape functions used in (ii)) — resulting in the inf–sup condition — is investigate through the numerical Chapelle-Bath test. Numerical validations are performed against analytical and finite element solutions on problems involving 1D or 2D boundaries embedded in a 2D or 3D background mesh. Comparisons with Nitsche’s method and the stable Lagrange multiplier space proposed in Hautefeuille et al. 2012, when they are feasible, highlight good performance of the approach. [less ▲]

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See detailEmbedded solids of any dimensions in the extended finite element method
Duboeuf, Frédéric ULiege; Béchet, Eric ULiege

Conference (2014, July 23)

First, we propose a new methodology to enforce Dirichlet boundary conditions in the X-FEM, available for every combination of the space and boundary dimensions. Second, we introduce a new algorithm to ... [more ▼]

First, we propose a new methodology to enforce Dirichlet boundary conditions in the X-FEM, available for every combination of the space and boundary dimensions. Second, we introduce a new algorithm to define a reduced function space over an embedded solid of arbitrary dimension. The combination of both algorithms allows to treat any embedding i.e. 1, 2 and 3D problems embedded in 2 or 3D background meshes. [less ▲]

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See detailEmbeddedness as a facilitator of sustainable entrepreneurship
Dufays, Frédéric ULiege

in Jermier, John; Nicolopoulou, Katerina; Karatas-Ozkan, Mine (Eds.) et al Sustainable entrepreneurship and social innovation (2016)

This conceptual paper makes the case for a strong embeddedness at all stages of sustainable entrepreneurship – opportunity identification and/or creation, evaluation, and exploitation. This strong ... [more ▼]

This conceptual paper makes the case for a strong embeddedness at all stages of sustainable entrepreneurship – opportunity identification and/or creation, evaluation, and exploitation. This strong embeddedness is argued to drive entrepreneurs towards sustainability through the set-up of long-term social contracts with multiple stakeholders. Building upon extant literature on sustainable, social, and environmental entrepreneurship and the framework of stakeholder theory, as well as the embeddedness argument, a model is developed and propositions are suggested. Theoretical and practical implications are derived from these propositions. [less ▲]

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See detailEmbeddedness as a facilitator of sustainable entrepreneurship
Dufays, Frédéric ULiege

Conference (2015, May 05)

This conceptual paper builds on stakeholder theory and the embeddedness argument to shift from the "what" to the "how" question on sustainable entrepreneurship. It shows that sustainable entrepreneurship ... [more ▼]

This conceptual paper builds on stakeholder theory and the embeddedness argument to shift from the "what" to the "how" question on sustainable entrepreneurship. It shows that sustainable entrepreneurship is a highly embedded process and that this high embeddedness facilitates the sustainability character of entrepreneurship. [less ▲]

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See detailEmbedding Anatomical or Functional Knowledge in Whole-Brain Multiple Kernel Learning Models
Schrouff, Jessica ULiege; Monteiro, Joao M.; Portugal, Liana et al

in Neuroinformatics (2018)

Pattern recognition models have been increasingly applied to neuroimaging data over the last two decades. These applications have ranged from cognitive neuroscience to clinical problems. A common ... [more ▼]

Pattern recognition models have been increasingly applied to neuroimaging data over the last two decades. These applications have ranged from cognitive neuroscience to clinical problems. A common limitation of these approaches is that they do not incorporate previous knowledge about the brain structure and function into the models. Previous knowledge can be embedded into pattern recognition models by imposing a grouping structure based on anatomically or functionally defined brain regions. In this work, we present a novel approach that uses group sparsity to model the whole brain multivariate pattern as a combination of regional patterns. More specifically, we use a sparse version of Multiple Kernel Learning (MKL) to simultaneously learn the contribution of each brain region, previously defined by an atlas, to the decision function. Our application of MKL provides two beneficial features: (1) it can lead to improved overall generalisation performance when the grouping structure imposed by the atlas is consistent with the data; (2) it can identify a subset of relevant brain regions for the predictive model. In order to investigate the effect of the grouping in the proposed MKL approach we compared the results of three different atlases using three different datasets. The method has been implemented in the new version of the open-source Pattern Recognition for Neuroimaging Toolbox (PRoNTo). [less ▲]

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See detailEmbedding Generalization in the Framework of a Large Scale Map Database
Genin, Bernard; Hubert, Alain; Donnay, Jean-Paul ULiege

in Proceedings of the Second Joint European Conference & Exhibition on Geographic Information (1996)

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See detailEmbedding Monte Carlo search of features in tree-based ensemble methods
Maes, Francis ULiege; Geurts, Pierre ULiege; Wehenkel, Louis ULiege

in Flach, Peter; De Bie, Tijl; Cristianini, Nello (Eds.) Machine Learning and Knowledge Discovery in Data Bases (2012, September)

Feature generation is the problem of automatically constructing good features for a given target learning problem. While most feature generation algorithms belong either to the filter or to the wrapper ... [more ▼]

Feature generation is the problem of automatically constructing good features for a given target learning problem. While most feature generation algorithms belong either to the filter or to the wrapper approach, this paper focuses on embedded feature generation. We propose a general scheme to embed feature generation in a wide range of tree-based learning algorithms, including single decision trees, random forests and tree boosting. It is based on the formalization of feature construction as a sequential decision making problem addressed by a tractable Monte Carlo search algorithm coupled with node splitting. This leads to fast algorithms that are applicable to large-scale problems. We empirically analyze the performances of these tree-based learners combined or not with the feature generation capability on several standard datasets. [less ▲]

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See detailEmbedding national procedural autonomy in the Directive on Damages’
Van Cleynenbreugel, Pieter ULiege

in Bergström, Maria; Iacovides, Marios; Strand, Magnus (Eds.) Harmonising EU Competition Litigation The New Directive and Beyond - See more at: http://www.bloomsburyprofessional.com/uk/harmonising-eu-competition-litigation-9781849467629/#sthash.KHNZiMg8.dpuf (2016)

This chapter outlines to what extent the EU damages Directive deviates from or takes into account the requirements of equivalence and effectiveness underlying the principle of national procedural autonomy ... [more ▼]

This chapter outlines to what extent the EU damages Directive deviates from or takes into account the requirements of equivalence and effectiveness underlying the principle of national procedural autonomy in EU law. Arguing that the Directive constitutes an operationalisation of those principles, the chapter outlines the strengths and limits of this approach chosen by the EU legislature. [less ▲]

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See detailEmbedding Open Science in Doctoral Education at the University of Liege
Halleux, Isabelle ULiege

in Doctoral Education Bulletin (2015)

This article is part of special issue on Open Research and Open education for early stage researchers. It presents good practices and main achievements in innovative and open Science doctoral training at ... [more ▼]

This article is part of special issue on Open Research and Open education for early stage researchers. It presents good practices and main achievements in innovative and open Science doctoral training at Ulg [less ▲]

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See detailEmbedding ‘‘Science and Society’’ within Nanotechnologies’ Development
Thoreau, François ULiege

Conference (2011, March 18)

These slides introduce nanotechnology as a voluntarist public policy. It addresses the societal dimensions of such policies, that is its social, ethical and legal aspects. It then focuses on one ... [more ▼]

These slides introduce nanotechnology as a voluntarist public policy. It addresses the societal dimensions of such policies, that is its social, ethical and legal aspects. It then focuses on one particular research project which aims at integrating such concerns into practices of research and development. Then, it raises issues, questions and ambiguities as for the role of social scientists in such a process. [less ▲]

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See detailThe Emblem in the European Stage (16th-18th c.)
De Marco, Rosa ULiege; Guiderdoni, Agnès

Book published by Glasgow Emblem Studies Librarie Droz (2018)

Detailed reference viewed: 28 (0 ULiège)
See detailL'emblématique de Louise de Savoie
Fagnart, Laure ULiege

Conference (2017, July 04)

Countess then duchess of Angoulême, Louise of Savoy (1476-1531) is the mother of two illustrious children, Marguerite, future Queen of Navarre, and Francis, future King Francis I. At the time her « Cesar ... [more ▼]

Countess then duchess of Angoulême, Louise of Savoy (1476-1531) is the mother of two illustrious children, Marguerite, future Queen of Navarre, and Francis, future King Francis I. At the time her « Cesar » become king, Louise dominates the Council and governs the kingdom as Regent, first in 1515-1516, then in 1523-1526. Our contribution will extend the analyses made by Anne-Marie Lecoq and Pierre-Gilles Girault, focussing on Louise of Savoy’s emblematic discourse. We will analyse her attire which clarifies the role she intended to play at the Court. We will also consider the Cord, one of the favourite devices of Louise of Savoy. [less ▲]

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See detailL’emblématique de Louise de Savoie
Fagnart, Laure ULiege; Girault, Pierre-Gilles

in Hablot, Laurent (Ed.) La devise. Un code emblématique européen (1350-1550) (in press)

Prolongeant les travaux d'Anne-Marie Lecoq (1987), cette étude est dédiée au discours héraldique de la comtesse et duchesse d'Angoulême, Louise de Savoie, l'influente mère de François Ier. Y sont ... [more ▼]

Prolongeant les travaux d'Anne-Marie Lecoq (1987), cette étude est dédiée au discours héraldique de la comtesse et duchesse d'Angoulême, Louise de Savoie, l'influente mère de François Ier. Y sont présentées et explicitées ses devises favorites, à savoir la cordelière, qui évoque autant le nœud de Savoie que la cordelière franciscaine, le vol, sans doute choisi puisque l’aile évoque le L de Louise par homophonie, le bouquet de lis ou le cygne « navré », mais aussi les écus et les monogrammes qui lui sont associés et qui ponctuent enluminures, tapisseries, bas-reliefs et éléments sculptés de l’architecture. Notre intention est de montrer d’une part comment Louise de Savoie manifeste, par l’intermédiaire de ces signes emblématiques, son identité et son pouvoir, d’autre part comment elle construit, par leur biais, un patrimoine, mental, susceptible de renforcer son clan et ses héritiers. [less ▲]

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See detailEmbodiment effects in memory for facial identity and facial expression
D'Argembeau, Arnaud ULiege; Lepper, Miriam; Van der Linden, Martial ULiege

in Cognition & Emotion (2008), 22

Research suggests that states of the body, such as postures, facial expressions, and arm movements, play central roles in social information processing. This study investigated the effects of approach ... [more ▼]

Research suggests that states of the body, such as postures, facial expressions, and arm movements, play central roles in social information processing. This study investigated the effects of approach/avoidance movements on memory for facial information. Faces displaying a happy or a sad expression were presented and participants were induced to perform either an approach (arm flexion) or an avoidance (arm extension) movement. States of awareness associated with memory for facial identity and memory for facial expression were then assessed with the Remember/Know/Guess paradigm. The results showed that performing avoidance movements increased Know responses for the identity, and Know/Guess responses for the expression, of valence-compatible stimuli (i.e., sad faces as compared to happy faces), whereas this was not the case for approach movements. Based on these findings, it is suggested that approach/avoidance motor actions influence memory encoding by increasing the ease of processing for valence-compatible information. [less ▲]

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See detailEmbodying the divine: herms in Greek vase-painting
Collard, Hélène ULiege

Conference (2014, March)

Detailed reference viewed: 27 (2 ULiège)
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See detail"Emboîtements cinématographiques : du prétexte narratif au discours imagé"
Belloi, Livio ULiege

Conference (2011, August 25)

Si un récit romanesque peut accueillir en abyme une réplique en miniature (Lucien Dällenbach), si, dans le même esprit, un tableau de peinture peut ouvrir son espace à un autre tableau de peinture (Victor ... [more ▼]

Si un récit romanesque peut accueillir en abyme une réplique en miniature (Lucien Dällenbach), si, dans le même esprit, un tableau de peinture peut ouvrir son espace à un autre tableau de peinture (Victor Stoichita), l’image de cinéma n’est pas en reste à cet égard : très tôt, elle s’est mise au miroir, par le procédé devenu canonique du film dans le film. En pareil cas d’espèce, le film premier convoque un film second, identifiable ou non, qui en constitue la glose ou la mise en ironie, selon des structures de redoublement variables. J'aborde ce phénomène de métadiscursivité au travers de deux sites d’images spécifiques : d’une part, le cinéma des premiers temps ; de l’autre, le cinéma expérimental contemporain. Dans le champ du cinéma des premiers temps, il s’agit d’examiner des occurrences assez précoces de réflexivité, au sein desquelles l’image seconde tient essentiellement lieu d’embrayeur narratif. Ainsi, dans "Erreur tragique" (1912) de Louis Feuillade, le personnage principal, assistant à une projection dans une salle de cinéma, a la surprise de voir apparaître sa propre épouse à l’écran, au bras d’un autre homme – prélude à un intense mélodrame conjugal. S’agissant du cinéma expérimental contemporain, l’image seconde se prête généralement à un enchâssement plus complexe au sein du film qui l’inclut et obéit plutôt à une exigence d’interrogation critique du cinéma par lui-même. Ce cas de figure sera envisagé au travers de "Tails" (1976) de Paul Sharits, œuvre méconnue dans laquelle le cinéaste, prolongeant le geste pionnier de Ken Jacobs ("Tom, Tom, the Piper’s Son", 1969), refilme des fragments de pellicule en mouvement et libère l’image seconde des contraintes imposées par le dispositif de projection, la mettant en situation de discourir muettement sur les propriétés physiques du film qui l’expose. [less ▲]

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See detailL'embolie pulmonaire
D'Orio, Vincenzo ULiege; NALDI, Marco ULiege

in Revue Médicale de Liège (1989), 24

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See detailL'embolisation scrotale antegrade de la varicocele--resultats.
Frangi, I.; Keppenne, Véronique ULiege; Coppens, Luc ULiege et al

in Acta Urologica Belgica (1998), 66(4), 5-8

The aim of this study is to judge the effectiveness of the new treatment of varicoceles, introduced in 1987 by Tauber: the antegradal scrotal sclerotherapy of varicoceles. From february 1996 to april 1998 ... [more ▼]

The aim of this study is to judge the effectiveness of the new treatment of varicoceles, introduced in 1987 by Tauber: the antegradal scrotal sclerotherapy of varicoceles. From february 1996 to april 1998, we have realised 150 antegrade embolisations of varicoceles. The study is lead on 75 patients with mean time follow-up of 12 months. Patient's mean age is 20 years. 85% of patients had a grade 3 left varicocele and 15% a grade 2 left varicocele. The criterium of success rests on the lack of veinous flow-back during clinical examination, which is than confirmed by doppler-ultrasound. Clinical success is obtained in 87% of the cases and the doppler control is normal in 80% of the cases. We have 9% of minor complications, and no major complication. The number of failures in our study is higher than in Tauber' study, but is the same as those described in the other procedures of treatment of varicocele. On the other hand the surgical procedure is simple and the morbidity is low. [less ▲]

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