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See detailArtificial Intelligence in Video Games: Towards a Unified Framework
Safadi, Firas ULg; Fonteneau, Raphaël ULg; Ernst, Damien ULg

in International Journal of Computer Games Technology (2015), 2015

With modern video games frequently featuring sophisticated and realistic environments, the need for smart and comprehensive agents that understand the various aspects of complex environments is pressing ... [more ▼]

With modern video games frequently featuring sophisticated and realistic environments, the need for smart and comprehensive agents that understand the various aspects of complex environments is pressing. Since video game AI is often specifically designed for each game, video game AI tools currently focus on allowing video game developers to quickly and efficiently create specific AI. One issue with this approach is that it does not efficiently exploit the numerous similarities that exist between video games not only of the same genre, but of different genres too, resulting in a difficulty to handle the many aspects of a complex environment independently for each video game. Inspired by the human ability to detect analogies between games and apply similar behavior on a conceptual level, this paper suggests an approach based on the use of a unified conceptual framework to enable the development of conceptual AI which relies on conceptual views and actions to define basic yet reasonable and robust behavior. The approach is illustrated using two video games, Raven and StarCraft: Brood War. [less ▲]

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See detailFrom photons to biomass in green microalgae: fluorimetric and oxymetric studies on the regulation of photosynthetic electron transport
de Marchin, Thomas ULg

Doctoral thesis (2015)

Analyzing the photosynthetic performances of microalgae has become an important topic in view of the ecological importance of these microorganisms and of the growing field of their biotechnological ... [more ▼]

Analyzing the photosynthetic performances of microalgae has become an important topic in view of the ecological importance of these microorganisms and of the growing field of their biotechnological applications. In this thesis, we developed methods which allow effective use of fluorescence and oxygen experimental signals for a more complete analysis of the functioning of the photosynthetic apparatus of green microalgae under different conditions. We applied these methods to analyze the adaptations of the photosynthetic apparatus under selected conditions, especially regarding CO2 supply. In the first part of this work, we applied a fluorescence-based method for determining the PSII antenna size based on the kinetics of the fast chlorophyll a fluorescence transient in presence of DCMU (or DCMU Fluorescence Rise). We then performed a detailed analysis of the different phases of this transient which are associated with different types of PSII formerly described as PSIIalpha and PSIIbeta (PSII heterogeneity). Our results on PSII heterogeneity during a transition from state 2 to state 1 in Chlamydomonas reinhardtii showed for the first time in vivo that this transition correlates with a conversion of PSIIbeta to PSIIalpha. We also discuss the possible relationships between PSIIalpha and PSIIbeta and the PSII mega-, super- and core- complexes described by biochemical studies. In photoautotophic atmospheric conditions, microalgae often have to deal with limited CO2 availability. The unicellular green algae Chlamydomonas reinhardtii can adapt to low CO2 concentration with the inorganic carbon concentration mechanism (CCM). This has been extensively studied in the past. However, other functional adaptations of the photosynthetic apparatus to CO2 limitation have been much less studied. In the second part of this work, we used combined fluorescence-based electron transport and oxygen measurements to evaluate the responses to low and high CO2 in Chlamydomonas reinhardtii grown in photobioreactors at different light intensities. We developed a method to rationalize the relationship between the apparent quantum yields of oxygen evolution and of electron transport at PSII while taking into account the variations in the proportion of energy absorbed by PSII. We used this relationship as a tool to evidence a significant O2-dependent alternative electron transport in low CO2 acclimated cells. We showed that this alternative electron transport can represent up to 60% of the total electron transport in low CO2 cells even upon removal of the CO2 limitation by bicarbonate addition. In contrast, no significant alternative electron transport was detected in high CO2 cells. We suggest that the alternative electron transport to O2 observed in low CO2 cells represents an adaptation that could help to meet the higher ATP demand for the concentration of CO2 by the CCM. In contrast, in high CO2 conditions, the absence of the CCM would reduce the need for ATP and thus the need for electron transport to O2. Using mutants and inhibitors, we studied the involvement of known O2-dependent electron sinks such as the mitochondrial cytochrome and alternative oxidase pathways and also of chlororespiration in this light-dependent O2 uptake and we found no evidence for the involvement of any of these processes. The alternative electron transport was even higher in a mitochondrial mutant devoid of complexes I and III and we suggest that this alternative electron transport could compensate for the absence of mitochondrial ATP synthesis in this mutant. By elimination, our results suggest that the alternative electron transport to O2 evidenced here could be driven by a Mehler-type reaction although we did not find direct evidences for increased Mehler-type activity in low CO2 cells. Additionally from fluorescence measurements performed directly in the cultures, we concluded that low CO2 cells had a lowest PSII photosynthetic efficiency and developed strong qE NPQ. Our results indicate that Chlamydomonas reinhardtii is capable to induce an ample thermal dissipation of excitation energy and the extent of this process is influenced essentially by the CO2 availability. In contrast with results obtained in previous studies, low temperature fluorescence spectra showed that in high light, high CO2 cells were characterised by a higher proportion of light energy absorbed by PSI compared to low CO2 cells. This was accompanied by a decrease of PSII antenna size as shown by DCMU-FR measurements. These findings are discussed in relation with the conflicting theories concerning the role of state transitions in the regulation of the cyclic electron transport around PSI. Our results support the idea that CEF is regulated by the redox state of the chloroplast rather than by state transitions. Over the last decades, microalgae have been increasingly studied because of their potential applications in industry. Despite a growing interest in microalgae mass cultures, the majority of studies on microalgae have been carried out at a laboratory scale and only few studies have addressed the question of photosynthetic adaptations in mass cultures. It is well known that CO2 addition increases the growth rate of microalgae and for this reason, some mass microalgae cultures are CO2 supplemented. Among the studies on microalgae mass culture, as far as we know, none directly compared high CO2 (CO2 supplemented air) and low CO2 (air) conditions. In the last part of our work, two outdoor open thin-layer cascade systems operated as batch cultures with the alga Scenedesmus obliquus were used to compare the productivity and photosynthetic adaptations in control and CO2 supplemented cultures in relation with the outdoor light irradiance. We found that the culture productivity was limited by CO2 availability beyond a threshold of daily irradiance. In the CO2 supplemented culture, we obtained a productivity of up to 25 g dw.m-2.day-1 and found a photosynthetic efficiency of 2.6%. Fluorescence and oxygen evolution measurements showed that ETR and oxygen evolution light saturation curves, as well as alternative electron transport were similar in algal samples from both cultures when the CO2 limitation was removed. In contrast, we found that CO2 limitation conducted to a decreased PSII photochemical efficiency and an increased light-induced heat-dissipation in the control culture compared to the CO2 supplemented culture. These features may contribute to the lower productivity observed in absence of CO2 supplementation in outdoor mass cultures of Scenedesmus obliquus. [less ▲]

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See detailPrevención cuaternaria y Clasificación Internacional de Atención Primaria, segunda edición.
Jamoulle, Marc ULg

Conference (2015, March 12)

Présentation des concepts de prevention quatenaire et de classification en soins primaires à la demande des autorités de l'université Isalud de Buenos Aires

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See detailSe "faire manger" par l'Autre. Stratégies féminines de définition de soi en contexte public.
Mescoli, Elsa ULg

Conference (2015, March 12)

Cette communication vise à étudier la participation des femmes migrantes marocaines à la vie sociale du « pays d’accueil » ; participation qui se réalise grâce aux activités de la vie quotidienne. En ... [more ▼]

Cette communication vise à étudier la participation des femmes migrantes marocaines à la vie sociale du « pays d’accueil » ; participation qui se réalise grâce aux activités de la vie quotidienne. En particulier, la performance publique des pratiques culinaires, observée dans une ville de la province de Milan, permet aux femmes considérées d’exercer une agency à l’intérieur des espaces institutionnellement concédés à l’expression des migrants. D’un côté, la consommation des « recettes de l’Autre » de la part de la population majoritaire détermine une incorporation de la diversité afin de la contrôler. De l’autre côté, la préparation de ces recettes consent aux migrantes d’exprimer leur subjectivité (individuelle et collective) de façon active et en présentant des aspects qui vont au-delà de la culture alimentaire. Une participation sociale fondée sur le partage de nourriture donne la possibilité aux femmes d’assumer un rôle actif dans la communauté locale, tout en affirmant ses propres spécificités. Des sujets tels que la liberté religieuse sont abordés, et certains droits peuvent être réclamés par des individus qui ont ainsi acquis une position politiquement importante au sein de la société locale. [less ▲]

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See detailDe quoi je me mêle ? Mais que vient faire l’Université dans l’effort de redéploiement économique et social ?
Rentier, Bernard ULg

Conference given outside the academic context (2015)

Le débat sur l'implication de l'Université dans l'activité économique de sa région ne date pas d'hier. Cette implication a même aujourd'hui acquis droit de cité en raison de plusieurs facteurs, positifs ... [more ▼]

Le débat sur l'implication de l'Université dans l'activité économique de sa région ne date pas d'hier. Cette implication a même aujourd'hui acquis droit de cité en raison de plusieurs facteurs, positifs et négatifs. Toutefois, aujourd'hui, ce volet de l'activité universitaire a pris une telle prépondérance que d'aucuns commencent à s'interroger sur l'ampleur du phénomène et à se demander si un rééquilibrage ne s'avère pas indispensable... Par ses recherches fondamentales, l'université apporte un renouveau d'idées, de concepts et de méthodes. Pour autant qu'un mécanisme prévoie un juste retour de moyens aux concepteurs et qu'un processus de conversion des avancées fondamentales et de développement vers l'application soit mis en place, le chercheur universitaire devrait se consacrer très largement à sa recherche de base. Un financement public suffisant permettrait cette focalisation et, partant, une meilleure efficacité. A défaut, le chercheur consacre une partie croissante de son temps à des développements d'applications qui le distraient de sa mission première et celle-ci en pâtit, concourant ainsi à ralentir le processus général d'innovation. Certes, il faut sortir le chercheur fondamentaliste de sa bulle (ou "tour d'ivoire") et il importe qu'il comprenne l'ensemble des rouages auxquels conduit son travail, mais il doit se focaliser sur l'amont plus que sur l'aval, sans quoi on verra se tarir la source de l'innovation (dont chacun s'accorde à dire qu'elle est génératrice de progrès). Certains ont une vocation plus appliquée et conviennent mieux pour les processus inventifs. Il est rare qu'une réelle sélection en vue de chacun de ces rôles soit assurée. Et, en général, la pénurie de moyens entraîne une usurpation des rôles. Quelles peuvent être aujourd'hui les perspectives pour un repositionnement plus performant ? [less ▲]

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See detailPhase Transformations and Crack Initiation in a High-Chromium Cast Steel Under Hot Compression Tests
Tchuindjang, Jérôme Tchoufack ULg; Neira Torres, Ingrid; Fores, Paulo et al

in Journal of Materials Engineering & Performance (2015)

The mechanical behavior of the fully austenitic matrix of high-chromium cast steel (HCCS) alloy is determined by external compression stress applied at 300 and 700 C. The microstructure is roughly ... [more ▼]

The mechanical behavior of the fully austenitic matrix of high-chromium cast steel (HCCS) alloy is determined by external compression stress applied at 300 and 700 C. The microstructure is roughly characterized toward both optical and scanning electron microscopy analyses. Dilatometry is used during heating from room temperature up to austenitization to study the solid-state phase transformations, precipitation, and dissolution reactions. Two various strengthening phenomena (precipitation hardening and stress-induced bainite transformation) and one softening mechanism (dynamic recovery) are highlighted from compression tests. The influence of the temperature and the carbide type on the mechanical behavior of the HCCS material is also enhanced. Cracks observed on grain boundary primary carbides allow establishing a rough damage model. The crack initiation within the HCCS alloy is strongly dependent on the temperature, the externally applied stress, and the matrix strength and composition. [less ▲]

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See detailLara Croft. Avatar, femme et icône du jeu vidéo
Barnabé, Fanny ULg

Conference given outside the academic context (2015)

La séduisante archéologue Lara Croft, protagoniste de la série de jeux Tomb Raider, est aujourd'hui l'une des icônes les plus célèbres du jeu vidéo, si bien qu'elle a même dépassé les limites de ce médium ... [more ▼]

La séduisante archéologue Lara Croft, protagoniste de la série de jeux Tomb Raider, est aujourd'hui l'une des icônes les plus célèbres du jeu vidéo, si bien qu'elle a même dépassé les limites de ce médium pour se faire connaître à un public élargi (à travers des adaptations au cinéma, en comics ou encore à travers des publicités). Toutefois, ce personnage est aussi une figure complexe qui a été reçue de manières très diverses : tantôt envisagée comme un symbole féministe (Lara Croft est une héroïne forte et indépendante, loin de la demoiselle en détresse à laquelle se cantonnaient généralement les premiers jeux vidéo), elle a aussi pu être interprétée comme une représentation caricaturale et réifiante de la femme. C'est donc d'un personnage chargé de contradictions que cette conférence propose de faire le portrait. [less ▲]

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See detailCerebellar hemorrhage : a rare condition in the term infant
MERINDOL, Ninon; BROUX, Isabelle ULg; DECORTIS, Thierry et al

Poster (2015, March 12)

Cerebellar hemorrhage is a rare condition in full-term newborns. Early diagnosis based on the identification of risk factors, particular clinical signs and correct medical imaging is primordial to ... [more ▼]

Cerebellar hemorrhage is a rare condition in full-term newborns. Early diagnosis based on the identification of risk factors, particular clinical signs and correct medical imaging is primordial to optimize the immediate treatment and to assess the long term prognosis. [less ▲]

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See detailSNOMED GP/FP RefSet and ICPC mapping Project 2010 -2015. Codificación y clasificación de diagnósticos en atención primaria y prevención cuaternaria.
Jamoulle, Marc ULg

Conference (2015, March 11)

Présentation des travaux du groupe de travail du Comité International de Classification de la Wonca sur la constitution d'un mappage entre la terminologie SNOMED-CT et la Classification Internationale de ... [more ▼]

Présentation des travaux du groupe de travail du Comité International de Classification de la Wonca sur la constitution d'un mappage entre la terminologie SNOMED-CT et la Classification Internationale de Soins Primaire ICPC-2 [less ▲]

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See detailLe métier de chercheur : Des parcours singuliers à la carrière traditionnelle profilée
Remy, Céline ULg; Balon, Floriane

Conference (2015, March 11)

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See detailClimate change : Impacts of shoreline erosion in developing countries
Ozer, Pierre ULg; Lemena, Kidja Hermann

Conference (2015, March 11)

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See detailElastic and inelastic transmission in guided atom lasers: A truncated Wigner approach
Dujardin, Julien ULg; Argüelles, Arturo; Schlagheck, Peter ULg

in Physical Review A (2015), 91

We study the transport properties of a Bose-Einstein condensate formed by an ultracold gas of bosonic atoms that is coupled from a magnetic trap into a one-dimensional waveguide. Our theoretical approach ... [more ▼]

We study the transport properties of a Bose-Einstein condensate formed by an ultracold gas of bosonic atoms that is coupled from a magnetic trap into a one-dimensional waveguide. Our theoretical approach to tackling this problem is based on the truncated Wigner method for which we assume the system to consist of two semi-infinite noninteracting leads and a finite interacting scattering region with two constrictions modeling an atomic quantum dot. The transmission is computed in the steady-state regime and we find a good agreement between truncated Wigner and matrix-product state calculations. We also identify clear signatures of inelastic resonant scattering by analyzing the distribution of energy in the transmitted atomic-matter wave beam. [less ▲]

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