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See detailMulti-Dimensional Vector Assignment Problems
Dokka, Trivikram; Crama, Yves ULg; Spieksma, Frits C.R.

in Discrete Optimization (in press)

We consider a special class of axial multi-dimensional assignment problems called multi- dimensional vector assignment (MVA) problems. An instance of the MVA problem is defined by m disjoint sets, each of ... [more ▼]

We consider a special class of axial multi-dimensional assignment problems called multi- dimensional vector assignment (MVA) problems. An instance of the MVA problem is defined by m disjoint sets, each of which contains the same number n of p-dimensional vectors with nonnegative integral components, and a cost function defined on vectors. The cost of an m-tuple of vectors is defined as the cost of their component-wise maximum. The problem is now to partition the m sets of vectors into n m-tuples so that no two vectors from the same set are in the same m-tuple and so that the sum of the costs of the m-tuples is minimized. The main motivation comes from a yield optimization problem in semi-conductor manufacturing. We consider a particular class of polynomial-time heuristics for MVA, namely the sequential heuristics, and we study their approximation ratio. In particular, we show that when the cost function is monotone and subadditive, sequential heuristics have a finite approximation ratio for every fixed m. Moreover, we establish smaller approximation ratios when the cost function is submodular and, for a specific sequential heuristic, when the cost function is additive. We provide examples to illustrate the tightness of our analysis. Furthermore, we show that the MVA problem is APX-hard even for the case m = 3 and for binary input vectors. Finally, we show that the problem can be solved in polynomial time in the special case of binary vectors with fixed dimension p. [less ▲]

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See detailLe speedrun : pratique compétitive, ludique ou créative ? Trajectoire d’un détournement de jeu vidéo institué en nouveau game
Barnabé, Fanny ULg

in Culture Numérique (in press)

Ce travail vise à interroger la manière dont les jeux vidéo et les dynamiques de détournement qu’ils suscitent chez les joueurs redéfinissent la traditionnelle opposition entre consommation et création ... [more ▼]

Ce travail vise à interroger la manière dont les jeux vidéo et les dynamiques de détournement qu’ils suscitent chez les joueurs redéfinissent la traditionnelle opposition entre consommation et création. Dans ce but, nous étudierons un usage spécifique du médium vidéoludique qui s’est institué en véritable pratique créative sur internet : le speedrun (et son dérivé, le tool-assisted speedrun). L’analyse se déroulera en deux temps : une première partie envisagera les déplacements concrets qu’opère le speedrun dans les notions liées au pôle de la réception (qu’est-ce qu’être un joueur ou un spectateur au sein de ce domaine ?) ; la seconde étudiera la façon dont cette pratique participe à redéfinir le pôle de la production (que deviennent les notions d’auteur, d’œuvre et de création dans le cadre de cette activité ?). [less ▲]

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See detailIsolating auroral FUV emission lines using compact, broadband instrumentation
Molyneux, P.M.; Bannister, N.P.; Bunce, E.J. et al

in Planetary and Space Science (in press)

Images of auroral emissions at far ultraviolet (FUV, 122–200 nm) wavelengths are useful tools with which to study magnetospheric-ionospheric coupling, as the scattered sunlight background in this region ... [more ▼]

Images of auroral emissions at far ultraviolet (FUV, 122–200 nm) wavelengths are useful tools with which to study magnetospheric-ionospheric coupling, as the scattered sunlight background in this region is low, allowing both dayside and nightside auroras to be imaged simultaneously. The ratio of intensities between certain FUV emission lines or regions can be used to characterise the precipitating particles responsible for auroral emissions, and hence is a useful diagnostic of magnetospheric dynamics. Here, we describe how the addition of simple transmission filters to a compact broadband imager design allows far ultraviolet emission ratios to be deduced while also providing large-scale instantaneous images of the aurora. The low mass and volume of such an instrument would make it well-suited for both small satellite Earth-orbiting missions and larger outer planet missions from which it could be used to characterise the tenuous atmospheres observed at several moons, as well as studying the auroral emissions of the gas giants. We present a study to investigate the accuracy of a technique to allow emission line ratio retrieval, as applied to the OI 130.4 nm and 135.6 nm emissions at Ganymede. The ratio of these emissions provides information about the atmospheric composition, specifically the relative abundances of O and O2. Using modelled FUV spectra representative of Ganymede's atmosphere, based on observations by the Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph (STIS), we find that the accuracy of the retrieved ratios is a function of the magnitude of the ratio, with the best measurements corresponding to a ratio of ∼1.3 . [less ▲]

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See detailSemiótica de la acción: textualización y notación
Dondero, Maria Giulia ULg

in Tópicos del seminario (2015), 31

Our essay focuses on some methodological issues concerning the semiotic analysis of practice. We will initially retrace the debate about the epistemological relationship between text and action, outlining ... [more ▼]

Our essay focuses on some methodological issues concerning the semiotic analysis of practice. We will initially retrace the debate about the epistemological relationship between text and action, outlining the forms of enunciative praxis through different levels of pertinence analysis. Secondly, we propose the concept of ‘textualization’ as a mediation between text and action: textualizations (photographs, videos, notes) organize and represent practices which are in themselves ephemeral and elusive. Finally, we will consider the textual diagrammatization that we call ‘notation’: this analytical form of mediation between text and practice does not have the same status of in-vivo textualisations, but it works like an ex-post reconstruction which highlights the main gestures and exchanges while performing their grammaticalization. A more general aim of this essay is an enquiry into the legitimate objects of textual semiotics: what are the objects that it can analyze without betraying its principle of immanence, but also without being confined to it and, as a consequence, being unable to analyze practices and respond to topical questions on social issues and on the research in the human sciences? [less ▲]

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See detailLa démocratie sous expertise. Médias, think tanks et privatisation du débat européen (en préparation, parution début 2015)
Geuens, Geoffrey ULg

Book published by Éditions du Croquant, coll. "Savoir / Agir" (2015)

L’ouvrage questionne la genèse des think tanks eurofédéralistes participant à la fabrication et à la légitimation des politiques d’intégration, avant de s’intéresser à ces autres agents sociaux de ... [more ▼]

L’ouvrage questionne la genèse des think tanks eurofédéralistes participant à la fabrication et à la légitimation des politiques d’intégration, avant de s’intéresser à ces autres agents sociaux de production et de diffusion de la pensée européenne que sont notamment les correspondants bruxellois et éditorialistes de quelques grands médias européens. L’ouvrage montre combien le discours journalistique sur l’Europe et le discours de certains « spécialistes » des questions européennes, qui trouve aussi à s’exprimer dans l’espace médiatique, sont la plupart du temps limités à quelques expressions stéréotypées et argumentaires clichés s’expliquant autant par la position occupée dans le champ du pouvoir par les agents qui s’en font les relais que par les dispositions de ces mêmes agents sociaux à l’égard du « projet européen ». [less ▲]

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See detailEffect of stress path on the miniaturizatio size effect for nickel polycrystals
Keller, Clement; Hug, Eric; Duchene, Laurent ULg et al

Conference (2015, January 04)

The mechanical behavior of mettalic materials deeply depends on the size of samples. For specimen dimensions de creasing from a few millimeters to a few micrometers, the general observed trend is a ... [more ▼]

The mechanical behavior of mettalic materials deeply depends on the size of samples. For specimen dimensions de creasing from a few millimeters to a few micrometers, the general observed trend is a softening of the mechanical behavior in tension which affects the stress level and the strain hardening. This effect is triggered by the derease of the number of grains across the thickness ( also called thickness"t" over grain size "d" ratio). The objective of this work is to provide new experimental results in order to analyse the miniaturization size effects for various stress paths without strain gradients across the thickness of the samples. To this aim, experimental tensil tests, large tensile tests and shear tests have been performed on Ni sheets ( 0.5mm) with various grain sizes ensuring different t/d ratios. Results show that the miniaturization softening is affected by triaxiality, the larger is this parameter, the lower is the mechanicval softening. These features seem to be linked to surface effects which are larger for low triaxiality stress paths. Attempts of numerical simulations using strain gradient crystal plasticity model are also performed to confirm the role played by surface effects. [less ▲]

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See detailA new species of Groenlandaspis Heintz, 1932 (Placodermi, Arthrodira) from the Famennian (Late Devonian) of Belgium
Olive, Sébastien ULg; Prestianni, Cyrille; Dupret, Vincent

in Journal of Vertebrate Paleontology (2015), 35(5),

A new species of the phlyctaeniid arthrodire genus Groenlandaspis from the upper Famennian of Belgium is described. The remains of Groenlandaspis potyi sp. nov. consist of dissociated thoracic armor ... [more ▼]

A new species of the phlyctaeniid arthrodire genus Groenlandaspis from the upper Famennian of Belgium is described. The remains of Groenlandaspis potyi sp. nov. consist of dissociated thoracic armor elements, but the specimen designed to be the holotype displays the median dorsal, anterior and posterior dorsolateral plates in connection. Though incomplete, the new species is characterized by an equilateral triangle-shaped median dorsal plate, a protruding posterodorsal apron of the posterior dorsolateral plate behind the overlap area for the median dorsal plate, and an overall lack of ornamentation. Groenlandaspis potyi sp. nov. constitutes the second occurrence of a Groenlandaspis species in continental Europe after the description of Groenlandaspis thorezi from upper Famennian quarries of Belgium. Another probable new species of Groenlandaspis is also described, though of unknown locality and horizon; it can however be deduced from the upper Famennian of Belgium without more precision. Together with some unpublished material of groenlandaspidids from the Famennian tetrapod-bearing locality of Strud, this material highlights the richness of the Groenlandaspididae diversity in Belgium. The discovery of Groenlandaspis potyi sp. nov. in Belgium reinforces the Famennian global distribution of this widespread genus during this period. Also, since those organisms have possibly been considered as non-marine indicators, this material is another argument pleading for close relationships between Euramerica and Gondwana around the Frasnian-Famennian boundary. [less ▲]

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See detailElsvier, Computers in Industry, Special Issue on Natural Language Processing and Text Analytics in Industry
Ittoo, Ashwin ULg; Bosh, v.d., Antal; Nguyen, Le Minh

Book published by Elsevier (2015)

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See detail"Des muets qui veulent parler". Lectures politiques, des Temps Modernes à L'Idiot de la famille
Cormann, Grégory ULg

in Bolmain, Thomas; Cormann, Grégory (Eds.) Politiques de la littérature. Bourdieu, Sartre, Foucault (2015)

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See detailRitournelles et territoires professionnels. Le cas des conseillers emploi
Orianne, Jean-François ULg

in Langage et Société (2015)

L’objectif de ce texte est d’utiliser le concept de ritournelle pour analyser la formation d’un groupe professionnel dans le champ des politiques d’emploi en Belgique : les conseillers emploi du FOREM ... [more ▼]

L’objectif de ce texte est d’utiliser le concept de ritournelle pour analyser la formation d’un groupe professionnel dans le champ des politiques d’emploi en Belgique : les conseillers emploi du FOREM. L’auteur commence par définir et opérationnaliser le concept, emprunté à Deleuze et Guattari, en suivant les apports des théories de la communication réflexive. Il esquisse brièvement le contexte politique et institutionnel au sein duquel le groupe professionnel apparaît. Ensuite, il analyse trois ritournelles professionnelles, trois procédés de territorialisation des identités professionnelles des conseillers emploi. Il précise, en conclusion, la complémentarité du concept de ritournelle avec celui de rhétorique professionnelle. [less ▲]

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See detailLa conception d’un programme de formation pédagogique pour des enseignants du supérieur : une démarche à insérer dans un cadre de développement professionnel
Poumay, Marianne ULg

in Daele, Amaury; Sylvestre, Emmanuel (Eds.) Le conseil pédagogique dans l’enseignement supérieur - Cadres de référence, outils de travail et de développement (2015)

Elaborer un programme de formation pour les enseignants est souvent le premier réflexe d’une cellule de conseillers pédagogiques nouvellement créée au sein d’une institution d’enseignement supérieur. Un ... [more ▼]

Elaborer un programme de formation pour les enseignants est souvent le premier réflexe d’une cellule de conseillers pédagogiques nouvellement créée au sein d’une institution d’enseignement supérieur. Un tel programme permet en effet une première sensibilisation aux questions d’apprentissage, une première étape dans ce qui pourrait devenir une réelle politique de développment professionnel pour les enseignants. Mais quelles sont les limites d’une telle approche ? Quelles sont ses conditions d’efficacité ? Au vu de quelques expériences européennes et notamment celle de l’université de Liège (Belgique), ce chapitre tente d’éclairer les défis majeurs qui attendent les conseillers pédagogiques au détour de leur conception d’un tel programme. [less ▲]

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See detailMamlūk Cairo: A Crossroad for Embassies
Bauden, Frédéric ULg; Dekkiche, Malika

Book published by Brill Academic Publishers (2015)

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See detailManuel. Les contrats spéciaux
Kohl, Benoît ULg; Burette, Caroline ULg; Daenen, Thomas et al

Book published by Larcier (2015)

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See detailLeibniz
Bouquiaux, Laurence ULg

in Bouaniche, Arnaud; Leclercq, Jean (Eds.) Une histoire de la philosophie (2015)

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See detailA mortar method combined with an augmented Lagrangian approach for treatment of mechanical contact problems
Cavalieri, Federico J.; Bruls, Olivier ULg; Cardona, Alberto

in Terze, Zdravko (Ed.) Multibody Dynamics: Computational Methods and Applications (2015)

This work presents a mixed penalty-duality formulation from an augmented Lagrangian approach for treating the contact inequality constraints. The augmented Lagrangian approach allows to regularize the non ... [more ▼]

This work presents a mixed penalty-duality formulation from an augmented Lagrangian approach for treating the contact inequality constraints. The augmented Lagrangian approach allows to regularize the non differentiable contact terms and gives a C1 differentiable saddle-point functional. The relative displacement of two contacting bodies is described in the framework of the Finite Element Method (FEM) using the mortar method, which gives a smooth representation of the contact forces across the bodies interface. To study the robustness and performance of the proposed algorithm, validation numerical examples with finite deformations and large slip motion are presented. [less ▲]

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See detailEnchanting gods and dolphins. A cross cultural analysis of uncanny encounters
Halloy, Arnaud; Servais, Véronique ULg

in Ethos (Berkeley, Calif.) (2015), 43(1),

Drawing on first–hand accounts of possession experiences in an Afro–Brazilian cult and Dolphin encounters at sea, we compare the two settings in order to identify the common features in people’s ... [more ▼]

Drawing on first–hand accounts of possession experiences in an Afro–Brazilian cult and Dolphin encounters at sea, we compare the two settings in order to identify the common features in people’s experiences, but also in the technologies of enchantment that make them possible. By “technology of enchantment”, we mean a space of practice, neither totally material, nor totally subjective, that supports “revelation”–like encounters with real or imagined intentional entities. Our analysis suggests that both types of experiences share at least five common traits: the presence of a prolific imagination marked by ontological and epistemological uncertainty; uncanny feelings; attentional focus on inner bodily and mental states; trance–like states; and an intentional shift from active to passive. The immersion of the individual in a sensorily organized environment (sensescape), made of distributed perceptual saliences, is found to play a central role in the merging of unusual body states with the imagination, which in turn enables the production of “new” embodied meanings belonging to enchantment. [less ▲]

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See detailLe chien des sciences de l'homme
Servais, Véronique ULg

Book published by Le bord de l'eau (2015)

L'ouvrage est divisé en deux parties. La première confronte différentes perspectives théoriques permettant de faire entrer le chien en sciences sociales. La seconde partie présente des études empiriques ... [more ▼]

L'ouvrage est divisé en deux parties. La première confronte différentes perspectives théoriques permettant de faire entrer le chien en sciences sociales. La seconde partie présente des études empiriques documentant la présence des chiens auprès des humains. [less ▲]

Detailed reference viewed: 13 (3 ULg)