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See detailFlexible multibody system modelling: A geometric local frame approach on SE(3)
Sonneville, Valentin ULg

Scientific conference (2015, October 30)

In order to improve computational costs in the frame of flexible multibody system modelling, we propose a geometrically exact framework relying on a local frame description. Thanks to this framework ... [more ▼]

In order to improve computational costs in the frame of flexible multibody system modelling, we propose a geometrically exact framework relying on a local frame description. Thanks to this framework, geometric non-linearities are strongly reduced for two reasons. Firstly, the equations of motion can be solved without introducing a global parametrization of the motion, which also leads to a naturally singularity-free description of large rotations. Secondly, the equations of motion are expressed in a local frame, both at position and rotation level, leading to intrinsic equations. Accordingly, these equations are insensitive to large amplitude motions, such that the geometric non-linearities are naturally filtered. The mathematical developments are carried out in a Lie group setting which, albeit more abstract than classical treatments, provides generic and powerful well established tools. So far, several elements have been formulated in this framework: rigid body, kinematic joints and a flexible beam finite element. A shell finite element and a super-element are also under development. Some interesting numerical advantages are observed following the reduction of geometric non-linearities, e.g., the iteration matrix depends on relative motion within the elements only and is thus invariant under rigid body motions. [less ▲]

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See detailBenedetto Varchi, gli artisti e l'accademia a Firenze
Geremicca, Antonio ULg

Scientific conference (2015, October 29)

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See detailLes visages d'Alain Baczynsky
Englebert, Jérôme ULg; Séguin, Marion

Scientific conference (2015, October 10)

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See detailEspace, temps et angoisse psychotique : à propos d'un cas magistral
Englebert, Jérôme ULg

Scientific conference (2015, October 10)

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See detailOuverture des travaux
Valenti, Gianluca ULg; Miesse, Hélène ULg

Conference (2015, October 01)

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See detailL’institution de la contre-culture
Saint-Amand, Denis ULg

Conference (2015, October)

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See detailFormer des enseignants soucieux de réduire les inégalités d'apprentissage ou comment tenir le cap entre réponse aux demandes et inertie. Analyse de cas d'un centre de formation d'enseignants en Fédération Wallonie-Bruxelles
Beckers, Jacqueline ULg; Simons, Germain ULg

Conference (2015, October)

Dans cette contribution, nous analyserons l'évolution des enjeux et priorités que s'est progressivement donné le Centre interfacultaire de formation des enseignants (Cifen) de l'Université de Liège depuis ... [more ▼]

Dans cette contribution, nous analyserons l'évolution des enjeux et priorités que s'est progressivement donné le Centre interfacultaire de formation des enseignants (Cifen) de l'Université de Liège depuis sa création officielle en 1995, et nous nous interrogerons sur leur pertinence. Comment prendre la mesure des changements effectivement mis en place, apprécier leur pertinence, réguler leurs effets, éviter l'essoufflement des partenaires du système ? Telles sont quelques unes des questions qui baliseront notre contribution. [less ▲]

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See detailL'énonciation énoncée dans l'image
Dondero, Maria Giulia ULg

in Colas-Blaise, Marion; Tore, Gian Maria; Perrin, Laurent (Eds.) Le sens de l’énonciation (2015)

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See detailAn enhanced version of a bone remodelling model based on the continuum damage mechanics theory.
Mengoni, Marlène ULg; Ponthot, Jean-Philippe ULg

in Computer Methods in Biomechanics & Biomedical Engineering (2015), 18(12), 1367-1376

The purpose of this work is to propose an enhancement of Doblaré and García's internal bone remodelling model based on the continuum damage mechanics theory. In their paper, they stated that the evolution ... [more ▼]

The purpose of this work is to propose an enhancement of Doblaré and García's internal bone remodelling model based on the continuum damage mechanics theory. In their paper, they stated that the evolution of the internal variables of the bone microstructure, and its incidence on the modification of the elastic constitutive parameters, may be formulated following the principles of Continuum Damage Mechanics, although no actual damage was considered. The resorption and apposition criteria (similar to the damage criterion) were expressed in terms of a mechanical stimulus. However, the resorption criterion is lacking a dimensional consistency with the remodelling rate. We here propose an enhancement to this resorption criterion, insuring the dimensional consistency while retaining the physical properties of the original remodelling model. We then analyse the change in the resorption criterion hypersurface in the stress space for a 2D analysis. We finally apply the new formulation to analyse the structural evolution of a 2D femur. This analysis gives results consistent with the original model but with a faster and more stable convergence rate. [less ▲]

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See detailBiotechnological potential of novel bacterial strains isolated on the brown alga Ascophyllum nodosum
Martin, Marjolaine ULg; Martin, Renée ULg; Barbeyron, Tristan et al

Conference (2015, August 18)

Bacteria associated with algae are underexplored despite their huge biodiversity and the fact that they differ markedly from those living freely in seawater. These bacterial communities are known to ... [more ▼]

Bacteria associated with algae are underexplored despite their huge biodiversity and the fact that they differ markedly from those living freely in seawater. These bacterial communities are known to represent great potential for the production of diverse bioactive compounds, such as specific glycoside hydrolases, as they interact in multiple complex ways with their host. Furthermore, enzymes from marine bacteria have original properties, like cold-adapted, halotolerant and highly stable, which are constantly searched out by bio-industries. The aim of our study was to identify bacteria, associated with the brown alga Ascophyllum nodosum, showing diverse polysaccharolytic activities. To isolate cultivable microorganisms, algal thalli of Ascophyllum nodosum were swabbed with sterile cotton tips and marine agar plates were inoculated. Three-hundred isolated bacteria were screened for agarase, kappa- and iota-carrageenase, and sulfatase activities on specific marine media. Thirty-two bacteria with polysaccharolytic activities were isolated and a part of their 16S rDNA (8F-1492R) were amplified and sequenced. Twenty-seven were classified as Flavobacteriia and five as Gammaproteobacteria. Putative new strains and species of Zobellia, Maribacter, Cellulophaga, Shewanella, Glaciecola, Pseudoalteromonas and Colwellia were identified by phylogenetic analysis. All those genera are well-known to colonize algal surface but only some of them are famous to degrade algal polysaccharides (Zobellia, Maribacter, Cellulophaga, and Pseudoalteromonas). However, all those novel bacterial strains/species showed multiple and diverse enzymatic activities (agarase, iota-and kappa-carrageenase, cellulase, beta-glucosidase, sulfatase and/or amylase activities). Genomics libraries with their DNA were constructed in Escherichia coli and Bacillus subtilis and are screened to identify the genes coding for the observed enzymatic activities. Those novel glycoside hydrolases from unknown marine bacteria should have original and innovative properties with great biotechnological potential. [less ▲]

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See detailPhysical modeling of lateral dike breaching due to overtopping
Rifai, Ismail; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in River, Coastal and Estuarine Morphodynamics, RCEM 2015 (2015, August)

Dikes are commonly used as defense structures for river flow channelization, protecting population and property from floods and against lateral riverbed migration. However, the aging of these structures ... [more ▼]

Dikes are commonly used as defense structures for river flow channelization, protecting population and property from floods and against lateral riverbed migration. However, the aging of these structures, combined with their increased vulnerability to extreme hydrological events may cause the dikes to breach, and subsequently to break. Furthermore, statistics show that flow overtopping is the main cause of dike failure, which emphasizes the need to understand thoroughly the process of breaching. Indeed, from a risk management perspective it is particularly important to have a detailed understanding of the mechanisms (e.g. internal erosion, overtopping erosion) underlying the formation of breaches due to overtopping and reliable information on flows passing through them. Conversely, the current knowledge of breaching mechanisms remains fragmented, especially because dike failure involves complex interactions between flows, materials of the structure, soil and foundations. The existing studies have addressed partially these interactions as the considered idealized dikes were generally homogenous, the piping erosion unaccounted for and the overtopping replicated in a dam-break like configuration. Yet, river embankments are subjected to high flow velocities parallel to the direction of the dike and to flow in the floodplain, which highly influence the shape of the breach and its evolution. The objective of the present work is to fill this gap. A laboratory experimental investigation is planned in the National Laboratory for Hydraulics and Environment (LNHE) of EDF R&D (France) and in the research group Hydraulics in Environmental and Civil Engineering (HECE) of the University of Liege (Belgium), reproducing realistic configurations of river dikes, accounting for the tangential flow in both main channel and floodplain. It enables thus the assessment of, on the one hand, the effect of the increase of the water level, and on the other hand, the influence of waves. The laboratory tests also consider the effect of a surface layer and composition of the dike core by testing different material mixtures. Geometry and composition of the idealized dikes are representative of typical field dikes, based on the similarity theory. [less ▲]

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See detailPaleoseismological record of the Hazar Lake along the East Anatolian Fault (Turkey)
Hubert, Aurelia ULg; Lamair, Laura ULg; Hage, Sophie et al

Poster (2015, July 27)

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See detailSedimentological and geochemical evidence to detect arid periods recorded in wadi deposits: a case study from northern Morocco
El Ouahabi, Meriam ULg; Bartz, Melanie; Rixhon, Gilles et al

Poster (2015, July 27)

Detailed reference viewed: 40 (3 ULg)
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See detailPersonnalité antisociale et psychopathologie
Englebert, Jérôme ULg

Conference (2015, July 14)

Notre communication a pour objectif de confronter les critères de la personnalité antisociale du DSM-IV et du DSM-5 à une réflexion psychopathologique. Nous commencerons par une analyse des différentes ... [more ▼]

Notre communication a pour objectif de confronter les critères de la personnalité antisociale du DSM-IV et du DSM-5 à une réflexion psychopathologique. Nous commencerons par une analyse des différentes contradictions propres au diagnostic qui nous mèneront à l’identification du critère « primaire » de cette entité qui est l’« incapacité à se conformer aux lois et normes sociales ». Nous confronterons ensuite à des situations cliniques l’hétérogénéité des profils pouvant répondre à ce diagnostic. Nos constats nous conduiront à mettre en doute la validité apparente du concept de personnalité antisociale, puisqu’il recouvre des modes de fonctionnement psychologique variés. La valeur discriminative faible, en matière de fonctionnement psychologique, suggère que c’est une dimension autre que psychopathologique qui organise ce diagnostic. Dénuée de toute attention pour les modes d’interactions, pour le vécu émotionnel et pour les états de subjectivité, la notion de personnalité antisociale ne porte pas d’intérêt à l’individu qu’elle catégorise, mais bien à l’acte délinquant commis par ce dernier. Nous conclurons sur le constat de l’absence de dimension psychopathologique de la personnalité antisociale, qui se révèle être un diagnostic principalement criminologique, à l’inverse des fondements de l’éthique psychopathologique. [less ▲]

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See detailBiogeographic variations in wood mice: Testing for the role of morphological variation as a line of least resistance to evolution
Renaud, Sabrina; Quere, Jean Pierre; Michaux, Johan ULg

in Cox, Philippe; Hautier, Lionel (Eds.) Cambridge Studies in Morphology and Molecules: New Paradigms in Evolutionary Biology ‘Evolution of the Rodents: Advances in Phylogeny, Paleontology and Functional Morphology’ (2015)

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See detailCorporate Disclosures, Information Asymmetry and Stock-Market Liquidity in France
Sougné, Danielle ULg; Ajina, Aymen; Lakhal, Faten

in Journal of Applied Business Research (2015), Vol 31(4),

This paper aims at studying the effect of corporate disclosures on information asymmetry and stock-market liquidity in France. Specifically, the purpose of this paper is to highlight the importance of ... [more ▼]

This paper aims at studying the effect of corporate disclosures on information asymmetry and stock-market liquidity in France. Specifically, the purpose of this paper is to highlight the importance of information included in the annual reports on investor’s behavior. This is proxied by the information asymmetry component of the bid-ask spread and stock market liquidity. Our sample includes 196 French listed firms over a period ranging from 2004 to 2007. We opt for an explanatory study using OLS regressions to examine the nature of the relationship between information disclosed in annual reports and bid-ask spreads a proxy for information asymmetry and stock market liquidity. The results show that the extent of corporate disclosures in annual reports positively influences the liquidity of the French market and negatively affects the adverse selection component of the bid-ask spread. This effect is further confirmed by the commitment to IFRS by French-listed firms from 2005. The decomposition of the total score in the sub-indices shows that non-financial and financial information are important in trading decisions while strategic information may be attractive only for long-term positions [less ▲]

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See detailTransnational routes for hyper-local practices. Homemade food of Moroccan migrant women in Italy.
Mescoli, Elsa ULg

Conference (2015, June 22)

Stemming from a doctoral research on the culinary practices of a group of Moroccan migrant women living in the north of Italy, this paper will focus on some narratives and habits concerning homemade food ... [more ▼]

Stemming from a doctoral research on the culinary practices of a group of Moroccan migrant women living in the north of Italy, this paper will focus on some narratives and habits concerning homemade food. This food was the result of the combination of hyper-local and transnational practices. In fact, preparing some food at home instead of buying it (bread, for example) was possible also thanks to the use of some ingredients that were bought in or coming from Morocco. The issue at stake was that of control: a control exerted at a hyper-local level (in one’s home) on procedures and at a transnational level (by personally knowing ingredients’ producers) on food elements. This combination let women prepare some representative food of their memory by using the traditional techniques learnt from their mothers and by excluding intermediations. Homemade food translated the reassuring utopia of keeping a link with a cultural belonging in spite of migration and of reducing the fear of being contaminated by the unknown products of the diversity. Some ethnographic data will be presented to show these dynamics, and they will be supported by the visual material collected through participant observation. [less ▲]

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See detailLa diversité linguistique en Asie Mineure et en Gaule à l'époque d'Irénée
Rochette, Bruno ULg

Conference (2015, June 11)

Detailed reference viewed: 27 (1 ULg)