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See detailGrammaire matérielle et erreur de catégorie
Leclercq, Bruno ULg

Conference (2015, May 08)

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See detailLe confesseur du Prince dans les Pays-Bas espagnols (1598-1659): une fonction, des individus.
Pirlet, Pierre-François ULg

Doctoral thesis (2015)

Cette thèse envisage, à la cour de Bruxelles (1598-1659), les rapports entre les pouvoirs séculiers et religieux au travers de la figure nodale du confesseur du Prince.

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See detailArtificial Intelligence in Video Games: Towards a Unified Framework
Safadi, Firas ULg

Doctoral thesis (2015)

The work presented in this dissertation revolves around the problem of designing artificial intelligence (AI) for video games. This problem becomes increasingly challenging as video games grow in ... [more ▼]

The work presented in this dissertation revolves around the problem of designing artificial intelligence (AI) for video games. This problem becomes increasingly challenging as video games grow in complexity. With modern video games frequently featuring sophisticated and realistic environments, the need for smart and comprehensive agents that understand the various aspects of these environments is pressing. Although machine learning techniques are being successfully applied in a multitude of domains to solve AI problems, they are not yet ready to enable the creation of fully autonomous agent that can reliably learn to understand the environments found in complex video games. 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 and realistic environment independently for each video game. These similarities, however, exist on a conceptual level. While video games do indeed share a variety of concepts, their interpretations vary from one game to another. Hence, these similarities can only be directly exploited at a conceptual level. Inspired by the human ability to detect analogies between games and apply similar behavior on a conceptual level, this thesis 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. Because conceptual AI is not tied to any game in particular, it benefits from a continuous development process as opposed to a development that is confined to the scope of a single game project. [less ▲]

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See detailArmée européenne : quelle phase transitoire ?
Dumoulin, André ULg

in Europe Diplomatie & Défense (2015), (792), 3

Page Idées sur la nécessité de créer les conditions d'une Union européenne de sécurité et de défense (UESD) à partir de quelques Etats membres de l'UE

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See detailFast Userspace Packet Processing
Barbette, Tom ULg; Soldani, Cyril ULg; Mathy, Laurent ULg

in Proceedings of ANCS 2015 (2015, May 07)

In recent years, we have witnessed the emergence of high speed packet I/O frameworks, bringing unprecedented network performance to userspace. Using the Click modular router, we first review and ... [more ▼]

In recent years, we have witnessed the emergence of high speed packet I/O frameworks, bringing unprecedented network performance to userspace. Using the Click modular router, we first review and quantitatively compare several such packet I/O frameworks, showing their superiority to kernel-based forwarding. We then reconsider the issue of software packet processing, in the context of modern commodity hardware with hardware multi-queues, multi-core processors and non-uniform memory access. Through a combination of existing techniques and improvements of our own, we derive modern general principles for the design of software packet processors. Our implementation of a fast packet processor framework, integrating a faster Click with both Netmap and DPDK, exhibits up-to about 2.3x speed-up compared to other software implementations, when used as an IP router. [less ▲]

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See detailFuture climate and surface mass balance of Svalbard glaciers in an RCP8.5 climate scenario: a study with the regional climate model MAR forced by MIROC5
Lang, Charlotte ULg; Fettweis, Xavier ULg; Erpicum, Michel ULg

in Cryosphere (The) (2015), 9

We simulated the 21st century Svalbard SMB with the regional model MAR (RCP8.5 scenario). Melt is projected to increase gently up to 2050 and then dramatically increase, with a larger increase in the ... [more ▼]

We simulated the 21st century Svalbard SMB with the regional model MAR (RCP8.5 scenario). Melt is projected to increase gently up to 2050 and then dramatically increase, with a larger increase in the south of the archipelago. This difference is due to larger ice albedo decrease in the south causing larger increase of absorbed solar radiation. The ablation area is projected to disappear over the entire Svalbard by 2085. The SMB decrease compared to present is projected to contribute 7mm to SLR. [less ▲]

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See detailChitosan-coated electrospun nanofibers with antibacterial activity
Croisier, Florence ULg; Sibret, Pierre ULg; Dupont-Gillain, Christine C. et al

in Journal of Materials Chemistry B (2015), 3(17), 3508-2517

Charged nanofibers were prepared by electrospinning (ESP) poly(ε-caprolactone) with a copolymer bearing carboxylic acid functions. The presence of these functions allowed exposing some negative charges on ... [more ▼]

Charged nanofibers were prepared by electrospinning (ESP) poly(ε-caprolactone) with a copolymer bearing carboxylic acid functions. The presence of these functions allowed exposing some negative charges on the fiber surface, by dipping the fibers in a phosphate buffer. A layer of chitosan, a polycation in acidic medium, was then deposited on the nanofiber surface, thanks to electrostatic attraction. Fibers were characterized at each step of the process and the influence of the copolymer architecture on chitosan deposition was discussed. The antibacterial activity of the resulting fibers was finally assessed. [less ▲]

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See detailLatin as literary Language in Constantinople ca. 400-700
Rochette, Bruno ULg

Scientific conference (2015, May 06)

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See detailSelf-defining memories and self-concept clarity: A comparative study of depressed patients, bipolar patients and healthy subjects
Wagener, Aurélie ULg; Boulanger, Marie ULg; Blairy, Sylvie ULg

Poster (2015, May 06)

Depressed and bipolar patients suffer from autobiographical memory (AM) deficits. For instance, depressed patients present an overgeneralisation and a mood congruence biases. Indeed, these patients seem ... [more ▼]

Depressed and bipolar patients suffer from autobiographical memory (AM) deficits. For instance, depressed patients present an overgeneralisation and a mood congruence biases. Indeed, these patients seem to have difficulties to recall specific and positive memories. The present study focusses on a particular kind of memories: the self-defining memories (SDMs). SDMs are highly pertinent for self-building: they help to define in the most clearly way our perception of ourselves. Because SDMs have not been studied a lot since yet in these two disorders, our goal is to assess the impact of general AM biases on SDMs. Then, the present study pursues two main aims: 1) To assess SDM’s characteristics, 2) To assess the relationship between SDM and self-concept clarity. To reach our objective, depressed and bipolar patients are compared to healthy subjects. Participants are asked to complete SDMs exercises that are recalling six important events which happened in their life. These SDMs are assessed on four variables: specificity, impact, meaning making, contain. Self-concept clarity and mood are also assessed. Until now, 17 depressed patients, 16 bipolar patients and 18 healthy controls participate in this study. Preliminary results do not highlight difference between our groups on specificity. Marginal effects appear for meaning making with healthy subjects recalling more meaning making events. Results show that depressed patients present a mood congruence. The final results will be presented during the convention, as data-collection is on-going and will end in April. Experimental and clinical implications of our results will be discussed. [less ▲]

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See detailA fungal biofilm reactor based on metal structured packing improves the quality of a Gla::GFP fusion protein produced by Aspergillus oryzae
Zune, Quentin ULg; Delepierre, Anissa ULg; Gofflot, Sebastien et al

in Applied Microbiology and Biotechnology (2015)

Fungal biofilm is known to promote the excretion of secondary metabolites in accordance with solid-state related physiological mechanisms. This work is based on the comparative analysis of classical ... [more ▼]

Fungal biofilm is known to promote the excretion of secondary metabolites in accordance with solid-state related physiological mechanisms. This work is based on the comparative analysis of classical submerged fermentation with a fungal biofilm reactor for the production of a Gla::GFP fusion protein by Aspergillus oryzae. The biofilm reactor comprises a metal structured packing allowing the attachment of the fungal biomass. Since the production of the target protein is under the control of the promoter glaB, specifically induced in solid-state fermentation, the biofilm mode of culture is expected to enhance the global productivity. Although production of the target protein was enhanced by using the biofilm mode of culture, we also found that fusion protein production is also significant when the submerged mode of culture is used. This result is related to high shear stress leading to biomass autolysis and leakage of intracellular fusion protein into the extracellular medium. Moreover, 2D-gel electrophoresis highlights the preservation of fusion protein integrity produced in biofilm conditions. Two fungal biofilm reactor designs were then investigated further, i.e. with full immersion of the packing or with medium recirculation on the packing, and the scale-up potentialities were evaluated. In this context, it has been shown that full immersion of the metal packing in the liquid medium during cultivation allows for a uniform colonization of the packing by the fungal biomass and leads to a better quality of the fusion protein. [less ▲]

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See detailUncertainty in Training-Image Based Inversion of Hydraulic Head Data Constrained to ERT Data : Workflow and Case Study
Hermans, Thomas ULg; Nguyen, Frédéric ULg; Caers, Jef

Scientific conference (2015, May 06)

In inverse problems, investigating the relationship between data and prior models and the uncertainty related to the posterior distribution of model parameters are as important as matching the data. In ... [more ▼]

In inverse problems, investigating the relationship between data and prior models and the uncertainty related to the posterior distribution of model parameters are as important as matching the data. In recent years, many efforts have been done to assess the posterior distribution of a given problem with reasonable computational costs through inversion techniques such as McMC. The derived posterior distribution is always dependent on the prior distribution. However, most of the studies ignore modeling the prior with realistic uncertainty. In this paper, we propose a workflow to assess the uncertainty of inversion of hydraulic heads data through the addition of electrical resistivity tomography (ERT) constraining data. The workflow is divided in three successive steps: 1) Construction of prior: we generate multiple alternative geological scenarios from literature data (architecture of facies) as well as site specific data (proportions of facies). Spatial uncertainty within each scenario is integrated hierarchically through geostatistics (multiple-point statistics simulation of facies constrained by ERT data as soft data). 2) Validation of prior scenarios: we transform prior facies scenarios into resistivity distribution scenarios through forward and inverse modeling. The scenarios are validated by comparison with field ERT data. The comparison is made through distance calculation and projection into a low dimensional space to calculate the probability of each scenario given field ERT data. 3) Matching dynamical data: we use the probability perturbation method, within each scenario, to integrate hydraulic heads to our models. We account for scenario probabilities, calculated in 2, in determining how many models per scenario we have to consider for building a reliable posterior distribution. The method is first applied on synthetic cases where the "true" model is known. Then, it is apllied a field case study in an alluvial aquifer (Belgium) where we consider prior uncertainty related to the type of elements (gravel channels or bars) and to their size. This study shows the importance of considering the uncertainty of the prior in inverse problems as it has a strong influence on model predictions and decision-making problems. [less ▲]

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See detailTowards a typology of hieroglyphic sign functions. Categorization and fluidity in the description of semiotic systems
Polis, Stéphane ULg

Scientific conference (2015, May 06)

The understanding of the functions of the signs in the hieroglyphic writing system has been an issue ever since knowledge of this script was lost during Late Antiquity. If ancient authors like Horapollo ... [more ▼]

The understanding of the functions of the signs in the hieroglyphic writing system has been an issue ever since knowledge of this script was lost during Late Antiquity. If ancient authors like Horapollo were still aware of the meaning of some hieroglyphs, they were often unable to correctly explain why these signs had such meanings. Jean-François Champollion’s famous Lettre à M. Dacier relative à l’alphabet des hiéroglyphes phonétiques (1822) was to change this state of affair, when the French scholar identified signs “doués de la faculté d’exprimer des sons”. In my lecture, I will review the insights of Egyptologists regarding the functions of hieroglyphs (from Champollion to contemporary scholars, like Kammerzell, Morenz, Schenkel, Vernus and Winand) and argue that the combination of three key-features — namely, semography, phonemography and autonomy — is necessary and sufficient in order to provide a description of the so-called ‘glottic’ functions of the ancient Egyptian graphemes. In a second part of the talk, I provide prototypical examples for each category and discuss interesting cases, which are somehow at the borders between categories, so as to illustrate the diachronic and synchronic gradience of the system. [less ▲]

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See detailConsultation citoyenne européenne sur la consommation durable du 25 octobre 2014. Rapport sur la consultation citoyenne organisée le 25 octobre 2014 à l'échelle de la Wallonie
Delvenne, Pierre ULg; Macq, Hadrien; Parotte, Céline ULg et al

Report (2015)

Le 25 octobre 2014, une vaste consultation citoyenne s’est déroulée simultanément dans 11 pays européens sur le thème de la consommation durable. Au total, ce sont un peu plus d’un millier de participants ... [more ▼]

Le 25 octobre 2014, une vaste consultation citoyenne s’est déroulée simultanément dans 11 pays européens sur le thème de la consommation durable. Au total, ce sont un peu plus d’un millier de participants qui ont pris part à la discussion à travers l’Europe. En Belgique, l’évènement se déroulait à l’échelle de la Wallonie et le panel citoyen a réuni 105 participants, sélectionnés selon des critères liés au genre, à l’âge, à la répartition géographique, au niveau d’études et à la catégorie socio-professionnelle. Les résultats de cette enquête participative montrent que tous, aussi bien citoyens-consommateurs, producteurs que décideurs politiques ont un rôle à jouer dans la consommation durable. Plus précisément, les participants ont exprimé la volonté que les élus encouragent la consommation durable et rendent son accès plus aisé aux citoyens. En conclusion, les 105 citoyens participant à cette journée se sont largement exprimés concernant leurs habitudes mais aussi leurs demandes vis-à-vis des pouvoirs publics concernant la consommation durable, un sujet auquel une écrasante majorité s’est déclarée très sensible. Outre les demandes citoyennes mises en exergue ci-dessus (éduquer et inciter à l’action quotidienne en faveur de la consommation durable, la rendre moins coûteuse, améliorer et renforcer l’offre de transports en commun), les participants ont également émis le souhait d’être davantage consultés dans la prise des décisions politiques, par le biais de mécanismes participatifs élargis au sein desquels ils peuvent jouer un rôle actif en soutien aux processus politiques. [less ▲]

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See detailDislocation et reconstruction d’un espace européen de la recherche scientifique, 1914-1920
Pirot, Pascal ULg

Scientific conference (2015, May 06)

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See detailSynthèse et applications catalytiques d'adduits zwitterioniques de carbènes N-hétérocycliques
Hans, Morgan ULg

Doctoral thesis (2015)

In 1991, Arduengo isolated and fully characterized the first N-Heterocyclic Carbene (NHC), thereby confirming the existence of these stable divalent carbon species postulated almost thirty years earlier ... [more ▼]

In 1991, Arduengo isolated and fully characterized the first N-Heterocyclic Carbene (NHC), thereby confirming the existence of these stable divalent carbon species postulated almost thirty years earlier by Wanzlick. Since then, the enthusiasm for these highly nucleophilic and strongly basic compounds has steadily increased in the scientific community. Their reactivity with respect to organic compounds is very rich and is relatively well documented since the middle of the 1960’s. Their strong electron-donicity and their moderate pi-acidity make them almost universal ligands. NHC complexes have indeed been prepared with practically all the metals from the periodic table. Their high nucleophilicity also allowed to successfully employ them as organocatalysts. The state of the art in these three fields as well as the properties of NHCs and their electronic and steric characterizations are discussed in the introduction of this manuscript. The second chapter is devoted to the synthesis and characterization of imidazol(in)ium dithiocarboxylates (NHC•CS2 adducts), carboxylates (NHC•CO2 adducts) and thiocarboxylates (NHC•COS adducts) and to their applications in organic synthesis and in coordination chemistry. First, because NHC•CO2 adducts do not require any reagents to generate free carbenes in solution, we proposed them as precursors of NHC to promote various Michael additions. Preliminary catalytic assays of a set of five representatives of this zwitterion family in a carba-Michael addition previously reported in the literature highlighted the net superiority of 1,3 dicyclohexylimidazolium carboxylate (ICy•CO2). Subsequently, we showed the efficiency of our catalytic system to promote sulfa-, and phospha-Michael additions. Eventually, the same precatalyst showed efficiency to initiate various sulfa-Michael/aldol organocascades. Second, we looked at the synthesis of a representative set of five imidazol(in)ium thiocarboxylates. Their characterization indicated a probable loss of the thiocarboxylate group. Hence, we tested their efficiency as carbene’s precursors in two benchmark reactions usually catalyzed by NHCs. 1,3-Dicyclohexylimidazolium thiocarboxylate (ICy•COS) turned out to be most effective to promote transesterification/acetylation, while 1,3 bis(2,4,6-trimethylphenyl)imidazolinium thiocarboxylate (SIMes•COS) afforded a quantitative yield in the benzoin condensation. Moreover, reaction of NHC•COS betaines with a half-equivalent of ruthenium dimer [RuCl2(p-cymene)]2 led to [RuCl2(p-cymene)(NHC•COS)] complexes in which the zwitterions were bonded to ruthenium by the sulfur atom only. This is a remarkable result because NHC•CO2 zwitterions behaved like efficient NHC precursors leading to metal-NHC complexes, while imidazol(in)ium dithiocarboxylates showed no signs of dissociation. They behaved as kappa2-S,S’ chelating ligands and led to metal-(S2C•NHC) complexes. Finally, catalytic tests of these new complexes bearing NHC•COS adducts in the Ring-Opening Metathesis Polymerization (ROMP) of cyclooctene, in the Atom Transfer Radical Polymerization (ATRP) of methyl methacrylate and in the synthesis of enol esters resulted in low yields. However, they provided evidence for the rearrangement of the starting complexes in Ru-NHC species under the experimental conditions adopted. The third chapter is devoted to the synthesis of azolium enolates and their characterization, as well as their involvement in the Staudinger reaction and to their coordination chemistry to ruthenium. Our interest initially focused on the general mechanism of the NHC-catalyzed Staudinger reaction. Literature reports two plausible mechanisms for the [2 + 2] cycloaddition between ketenes and electron-poor imines. The first one, called "Imine-first" involves an azolium amide, while the second one, called "Ketene-first" goes through an azolium enolate. Synthesis and full characterization of these two types of zwitterionic adducts combined with their catalytic assay in the reaction between diphenylketene and N-tosylbenzaldimine allowed us to acquire a strong experimental evidence in favor of the "Ketene-first" observed path. We were then interested by probing the diastereoselectivity observed during NHC catalyzed [2 + 2] cycloadditions between unsymmetrical ketenes and various N sulfonylbenzaldimines. In order to investigate the parameters that influenced the stereoselectivity during these reactions, we prepared and fully characterized two new betaines (S)IMes•EtPhC=C=O and we performed catalytic assays in the reaction between ethylphenylketene and different N-sulfonylbenzaldimines, during which we varied various experimental parameters. We showed that steric hindrance of the catalyst is critical, poorly hindered NHCs favoring cis diastereoisomers, while trans-beta-lactams were essentially produced when more congested catalysts were used. The reaction solvent is also a critical parameter, N,N-dimethylformamide allowing to obtain the best diastereoisomeric ratio, 16:84, in favor of the trans isomer. Finally, the reaction temperature and the nature of the substituent on the N-sulfonylated imine are less important. The last part of this chapter concerned the coordination of NHC•ketene adducts to ruthenium. Our starting hypothesis was that these betaines could provide simultaneously an NHC ligand and an alkylidene precursor (a ketene) to the metal. By this way and from adequate metallic precursors, we envisioned to synthetize second-generation Grubbs type complexes, benchmark catalysts for olefin metathesis, in one step and without the need to handle diazo compounds. Although the first exploratory experiments did not lead to the expected results, they provided crucial information to help achieve these syntheses in future investigations. [less ▲]

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See detailProteome variations in Macrobrachium rosenbergii exposed to chlordecone: a gel-free proteomic approach
Lafontaine, Anne ULg; De Pauw, Edwin ULg; Forget-Leray, Joelle et al

Poster (2015, May 06)

Detailed reference viewed: 14 (4 ULg)