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See detailA Receding Horizon Approach to Incorporate Frequency Support into the AC/DC Converters of a Multi-Terminal DC Grid
Papangelis, Lampros ULg; Panciatici, Patrick; Debry, Marie-Sophie et al

in Electric Power Systems Research (2017)

This paper proposes a novel control scheme for provision of frequency support among asynchronous AC areas through HVDC grids. It is based on local controllers, each acting on a voltage source converter ... [more ▼]

This paper proposes a novel control scheme for provision of frequency support among asynchronous AC areas through HVDC grids. It is based on local controllers, each acting on a voltage source converter, using local measurements only, and supporting frequency of the adjacent AC area after a significant disturbance. The new discrete control is combined with the existing DC voltage droop technique. The formulation, inspired of Receding Horizon Control, enables providing to the AC area the desired frequency support, while at the same time taking into account various constraints, such as maintaining the DC voltage between secure operating limits. Examples obtained from a test system with a five-terminal DC network connecting two asynchronous areas demonstrate the effectiveness and robustness of the proposed control scheme in various scenarios, with emphasis on component failures. [less ▲]

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See detailReinforcement Learning for Electric Power System Decision and Control: Past Considerations and Perspectives
Glavic, Mevludin ULg; Fonteneau, Raphaël ULg; Ernst, Damien ULg

in The 20th World Congress of the International Federation of Automatic Control, Toulouse 9-14 July 2017 (2017, July)

In this paper, we review past (including very recent) research considerations in using reinforcement learning (RL) to solve electric power system decision and control problems. The RL considerations are ... [more ▼]

In this paper, we review past (including very recent) research considerations in using reinforcement learning (RL) to solve electric power system decision and control problems. The RL considerations are reviewed in terms of speci c electric power system problems, type of control and RL method used. We also provide observations about past considerations based on a comprehensive review of available publications. The review reveals the RL is considered as viable solutions to many decision and control problems across di erent time scales and electric power system states. Furthermore, we analyse the perspectives of RL approaches in light of the emergence of new-generation, communications, and instrumentation technologies currently in use, or available for future use, in power systems. The perspectives are also analysed in terms of recent breakthroughs in RL algorithms (Safe RL, Deep RL and path integral control for RL) and other, not previously considered, problems for RL considerations (most notably restorative, emergency controls together with so-called system integrity protection schemes, fusion with existing robust controls, and combining preventive and emergency control). [less ▲]

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See detail"Exploring Experiences of Inequality in European Urban Centers: Towards an Intersectional and Transnational Approach."
Vivas Romero, Maria ULg; Ramos, Cristina

Conference (2017, June 28)

What strategies do migrants living in European cities use to challenge inequalities in access to healthcare, participation in the labor market and the creation of social support networks? The papers in ... [more ▼]

What strategies do migrants living in European cities use to challenge inequalities in access to healthcare, participation in the labor market and the creation of social support networks? The papers in this panel aim to respond to this question by drawing from transnational and intersectional approaches conceptualizing inequalities as sets of relationships between people and broader structures in which interactions generate better opportunity for some more than for others (Tilly, 2000). Panel participants consider that these interactions and the benefits that can be obtained through migration are affected by various social categories such as gender, class, sexual identity, transnational connections, and citizenship. Intersectional approaches allow to examine how these axes of inequality (Crenshaw, 1989; Anthias, 2001) simultaneously affect migration outcomes and also how they operate differently according to the geographical space in which they develop: origin and host societies as well as transnationally. Nonetheless, the papers presented in this panel will also emphasize migrants’ agency to resist or conform to the inequalities they face. Overall, this panel aims to contribute to the study of migration and inequality at the conceptual and methodological levels. At the theoretical level, the panel will build on new debates on the reproduction of intersectional inequalities in transnational settings (Faist, 2016, Amelina, 2017). At the methodological level, all paper presenters have use multi-sited ethnographic methods (working in cities such as Madrid, London, Milan, Brussels and Frankfurt) and will therefore use the panel as an opportunity to discuss the strengths and weaknesses of such method. [less ▲]

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See detailSartre et la radio : Création sonore et table ronde
Cormann, Grégory ULg; Hamers, Jérémy ULg

Conference (2017, June 24)

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See detailLa comparaison en Belgique
Delville, Michel ULg

Conference (2017, June 22)

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See detailUHPLC-ESI-MS/MS quantitation of natural estrogens in aqueous matrices as pyridine-3-sulfonyl derivatives
Glineur, Alex ULg; Ronkart, Sébastien; Nott, Kathérine et al

Conference (2017, June 22)

Natural estrogens (estrone: E1, 17-β-estradiol : E2, estriol : E3) and synthetic estrogen (17-α-ethinylestradiol: EE2) are powerful endocrine disruptors. They may have deleterious effects on aquatic ... [more ▼]

Natural estrogens (estrone: E1, 17-β-estradiol : E2, estriol : E3) and synthetic estrogen (17-α-ethinylestradiol: EE2) are powerful endocrine disruptors. They may have deleterious effects on aquatic wildlife and also humans even at extremely low concentrations. For this reason, these molecules have been included in a watch list from the European Commission regarding emerging aquatic pollutants. The maximum detection limits are set at 0.035 and 0.40 ng/L for EE2 and E1, E2 respectively. Reaching such low levels of concentration of estrogenic compounds is a challenge, even using state-of-the-art analytical methods. In this study, we developed a UHPLC-ESI-MS/MS method allowing the quantification of E1, E2, E3 and EE2 residues in aqueous matrices. Studies commonly used ESI in negative mode albeit the poor ionization efficiency of native estrogenic compounds in this mode. In this study, the molecules were derivatised using a sulfonyl chloride reagent (pyridine-3-sulfonyl, P-3-S). The resulting response in the positive mode was significantly enhanced. Similarly to other dansyl derivatives, the product ion spectra of the P-3-S derivatives indicate ions originating from the derivatization reagent moiety. Moreover, several other ions were included in the product ion spectra of the P-3-S derivatives. Their specificity was assessed by a qualitative approach implying the analysis of different types of water samples (groundwater, surface water). Some product ions were found to be noticeably better for quantification and confirmation of the analytes. The developed analytical method was validated according to the NF T90-210 norm which is suitable to assess the performances of a method in the water quality field. The limits of quantification were 0.04, 0.05, 0.10 and 0.02 ng/L in groundwater and 0.89, 0.79,4.42 and 0.29 ng/L in surface water for E1, E2, E3 and EE2 respectively. [less ▲]

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See detailChromatographic analysis of alkaloids in Aconitum pollen : towards new insights in plant protection mechanisms
Vanderplanck, Maryse ULg; Glauser, Gaëtan; Tyteca, Eva ULg et al

Conference (2017, June 19)

Alkaloids are a class of naturally occurring organic nitrogen-containing bases that are found primarily in plants. They display a huge diversity with more than 3,000 different types already identified ... [more ▼]

Alkaloids are a class of naturally occurring organic nitrogen-containing bases that are found primarily in plants. They display a huge diversity with more than 3,000 different types already identified. Next to their different pharmacological and therapeutic effects, alkaloids can have a deleterious impact on organisms as they are known to be neurotoxic and cardiotoxic for mammals and insects. In the current context of worldwide bee decline, occurrence of such compounds in floral production, i.e. nectar and pollen, raises major concerns. They could be beneficial to bees by protecting them against disease and pathogens but they could also cause toxicity. Until now alkaloids, and their effect on human health, are mainly studied in vegetative parts of plants. More recently the natural occurrence of alkaloids in nectar was also studied to investigate their effect on bee health. Whereas nectar chemicals can relatively easily and quickly be analyzed by chromatography, extracting chemicals from low pollen amount remains a challenge because of pollen structure and complexity. However, characterization of pollen chemicals can lead to valuable insight in their impact on pollinators allowing the development of mitigation strategies. In this study, we used a UHPLC-(ESI)-Q-ToF/MS method allowing the identification and quantification of alkaloids in pollen matrices from four Aconitum species; A. lycoctonum, A. napellus compactum, A. napellus neomontanum and A. variegatum. Alkaloid extraction was performed using bead-beating disruption of the pollen sample and chromatographic analysis was carried out on an Acquity UPLC system interfaced with a Synapt G2 QTOF. The separation was achieved in gradient mode on an Acquity UPLC BEH C18 column and detection was performed in electrospray positive ionization mode (ES+). Alkaloid concentrations were measured as aconitine equivalents by using a pure aconitine standard as reference compound. The total amount of alkaloids in Aconitum pollen ranged from 0.75 to 1.20 mg/g with 859 different compounds detected, some of them being pollen-specific. Statistical analyses were conducted on the global dataset to assess both quantitative and qualitative interspecific differences. One-way analysis of variance was performed on the total alkaloid content while a permutational test of multivatiate analysis of variance was used to compare the alkaloid profiles among the four Aconitum species. Results are briefly discussed in an ecological context. [less ▲]

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See detailNCA independence in the context of EU Regulation 1/2003: time to take incongruent accountability realities (more) seriously?
Van Cleynenbreugel, Pieter ULg

Scientific conference (2017, June 16)

This paper argues that the Commission’s reform suggestions aimed at streamlining NCAs into independent administrative agencies appear to neglect this variety of accountability mechanisms underlying ... [more ▼]

This paper argues that the Commission’s reform suggestions aimed at streamlining NCAs into independent administrative agencies appear to neglect this variety of accountability mechanisms underlying current NCA institutional organisation and functioning. Given that those mechanisms each harbour incongruent expectations regarding the organisation and functioning of independent NCAs, failure to acknowledge such incongruence may in practice lead to less effective competition law enforcement. The purpose of this paper is therefore to uncover the different NCA independence perspectives underlying those accountability mechanisms and to look for legally sound ways to make them converge when designing or upgrading NCA independence in the context of the Regulation 1/2003 reform. [less ▲]

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See detailLegal presumptions of fault in the wake of the transposition of Directive 2014/104/EU
Van Cleynenbreugel, Pieter ULg

Scientific conference (2017, June 14)

This paper looks at the role played by legal presumptions in the transposition of the directive on damages and whether this differs from the use of legal presumptions in other contexts of EU competition ... [more ▼]

This paper looks at the role played by legal presumptions in the transposition of the directive on damages and whether this differs from the use of legal presumptions in other contexts of EU competition law enforcement. [less ▲]

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See detailAnalyse qualitative et méthodes (a)preceptives
Englebert, Jérôme ULg

Scientific conference (2017, June 13)

Detailed reference viewed: 44 (0 ULg)
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See detailTowards Mixed-Type Modelling of Structures with Slender and Deep Beam Elements
Liu, Jian ULg; Mihaylov, Boyan ULg

Conference (2017, June 12)

Concrete frame structures often include both slender and deep beams. Deep beams possess a large shear capacity, and thus are typically used as transfer girders to carry heavy loads over large spans. The ... [more ▼]

Concrete frame structures often include both slender and deep beams. Deep beams possess a large shear capacity, and thus are typically used as transfer girders to carry heavy loads over large spans. The overloading of such members due to extreme events such as earthquakes may result in the collapse of the entire structure. To evaluate the resilience of large frame structures under extreme loading, it is necessary to model the interaction between the deep girders and the rest of the structure in an accurate and computationally effective manner. To address this issue, this paper proposes a mixed-type modelling framework by formulating an innovative 1D macro deep-beam element and coupling it with 1D slender elements. The new macro element aims to combine the accuracy of 2D micro finite elements with the simplicity of 1D macro elements. The paper summarizes the formulations of this element, based on the three-parameter kinematic theory, and integrates it into an existing global nonlinear analysis procedure to create a mixed-type modeling framework. The verification study, including a frame structure with a deep transfer girder, has shown that this approach captures the response of the frame with an accuracy similar to that of 2D micro finite elements, while requiring approx. 20% of the analysis time. [less ▲]

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See detailImpact of formulation and process parameters on near-infrared spectra: Application for water determination in biopharmaceuticals
Clavaud, Matthieu ULg; Roggo, Yves; Allmendinger, Andrea et al

Poster (2017, June 11)

Traditionally, the water content of freeze-dried biopharmaceuticals is determined by time-consuming methods such as Karl Fischer titration. As a fast and non-destructive method, many studies demonstrated ... [more ▼]

Traditionally, the water content of freeze-dried biopharmaceuticals is determined by time-consuming methods such as Karl Fischer titration. As a fast and non-destructive method, many studies demonstrated the efficiency of Near-Infrared (NIR) spectroscopy for that purpose [1]. In this study, NIR was applied to different freeze-dried monoclonal antibody. The aim was to evaluate the robustness of a NIR model depending on formulation composition and process parameters of the lyophilization parameters, and the benefits of NIR when developing a freeze-drying cycle for a new pharmaceutical product. A full Design of experiments (DoE) was established in order to produce materials with various formulations and various process parameters. As a first step, a calibration model was created and validated. The model creation was based on 4 target lyophilized cycles which were manufactured to obtain samples with different water content concentration. Then, 20 lyophilized cycles were produced according to the DoE. Two levels of protein and sucrose concentration, and two levels of pressure / primary drying temperature and process time were investigated. Furthermore, several samples of each experiment stored at different temperature and relative humidity conditions were evaluated. Chemometrics using Principal Component Analysis (PCA) and Partial Least Squares (PLS) were used to evaluate the process variations and to determine the water content, respectively. NIR is capable to differentiate between different lyophilization process conditions, based on chemometrics. Robust calibration NIR model for water determination was generated against KF independent on lyophilization process parameters and formulation composition. NIR is suitable and robust method for drug product development of freeze-dried formulation. [less ▲]

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See detailThe roles of competition law in a regulated digital market environment: lessons (not) to learn from related fields of EU regulation
Van Cleynenbreugel, Pieter ULg

Scientific conference (2017, June 09)

Within the framework of its Digital Single Market (DSM) agenda, the European Union proposes the adoption of new legislative proposals aimed at removing remaining obstacles to digital transactions ... [more ▼]

Within the framework of its Digital Single Market (DSM) agenda, the European Union proposes the adoption of new legislative proposals aimed at removing remaining obstacles to digital transactions. Proposals relate to the abolition of geo-blocking as well as data and copyright portability. Complementing competition law provisions, those initiatives would seek to create the conditions for a competitive e-commerce environment within the EU internal market. In doing so, the Commission implicitly but clearly seeks to replicate a regulatory and policy approach it had taken already from the 1990s onwards when liberalising the energy and electronic communication sectors. It can be submitted that the European Commission, in proposing its DSM regulation strategy and in setting the terms of its e-commerce sector inquiry, has paid insufficient attention so far to the various and complementary roles competition law can play in a more strictly regulated market environment. In an attempt to clarify the scope and role of EU competition law and its enforcement in a digital single market environment and to guarantee its coherent application with the proposed DSM regulations, this paper will reflect on the roles competition law can our should still play in this context. Proceeding in three parts, the first part of the paper will chart the interaction between competition law and market regulation proposals in the EU’s DSM context. Using examples from the geo-blocking, data portability and copyright proposals made, this part highlights how the EU institutions perceive the interaction between competition law provisions and market regulation in this context. On the basis of that analysis, the second part will frame the interaction between competition law and market regulation as perceived in the DSM strategy, by comparing it with earlier examples in the realm of energy and electronic communications. In doing so, this part will identify two important similarities (breaking up barriers to trade and facilitating cross-border competition) as well as two fundamental differences (absence of natural monopolies and of intensely state regulated sectors). Acknowledging those similarities and differences, it will be submitted, allows better to conceptualise the role of competition law in the particular DSM context. To that extent, the third part will present and analyse the tenability of three possible roles competition law can still play against this background. Assessing the advantages and limits of each approach, that part will invite the Commission to take a clearer stance regarding the choice of one of them. [less ▲]

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See detailFire risk assessment of multi-story buildings based on fragility analysis
Gernay, Thomas ULg; Elhami Khorasani, Negar; Garlock, Maria

in Proceedings of the 2nd International Fire Safety Symposium - IFireSS 2017 (2017, June 08)

Recent efforts aim at assessing the fire performance of structures in a probabilistic framework. But there is still no well-established method to quantify the reliability of entire buildings. Previous ... [more ▼]

Recent efforts aim at assessing the fire performance of structures in a probabilistic framework. But there is still no well-established method to quantify the reliability of entire buildings. Previous works focused on isolated structural members, therefore not allowing for a determination of the global safety level of buildings. Here, a new methodology is developed to quantify the reliability of buildings in fire. The methodology uses Monte Carlo simulations for constructing fragility functions associated with different fire breakout locations in a building, then combines the functions to characterize the overall building conditional probability of failure, and finally incorporates the probabilistic models for intensity measure and fire occurrence likelihood. The methodology is applied to multi-story steel buildings. This work addresses fire reliability at the building scale, and therefore is useful for standardizing safety level as well as for evaluating community resilience. [less ▲]

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See detailFire resistance of concrete slabs acting in compressive membrane action
Molkens, Tom; Gernay, Thomas ULg; Caspeele, Robby

in Proceedings of the 2nd International Fire Safety Symposium - IFireSS 2017 (2017, June 08)

In building renovation, the real behaviour of reinforced concrete slabs cannot always be explained by the bending theory according to classical structural mechanics. Indeed, the bearing capacity, as ... [more ▼]

In building renovation, the real behaviour of reinforced concrete slabs cannot always be explained by the bending theory according to classical structural mechanics. Indeed, the bearing capacity, as assessed for instance by a loading test, sometimes appears to be much higher than what would be expected. This phenomenon may be caused by the activation of an arch-effect or so-called compressive membrane action (CMA) which can develop even with small vertical deformations. For a slab which is completely restrained, the presence of reinforcement becomes of lesser importance when this phenomenon is activated (except for end fields). Hence, for fire resistance purposes, it can be discussed whether reinforcement and concrete cover has a smaller influence on the bearing capacity for slabs subjected to fire which exhibit a significant concrete compressive membrane behaviour. This paper presents a loading test performed on a real concrete building which highlighted the development of CMA as the load bearing mode. It then proposes a strategy to evaluate the behaviour resulting from the development of CMA in reinforced concrete slabs at ambient and at elevated temperature based on numerical modelling. The numerical analyses are performed with the finite element software SAFIR® using a strip of layered shell elements. A plastic-damage constitutive model with an explicit transient creep formulation is used to capture the concrete behaviour at elevated temperature. [less ▲]

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See detailLa reconnaissance de la maladie mentale en psychopathologie légale
Englebert, Jérôme ULg

Conference (2017, June 01)

De nombreux programmes thérapeutiques recommandent d’orienter la thérapie sur la reconnaissance du trouble ou de la maladie. Nous évoquerons cette problématique dans le cadre de la psychiatrie légale ... [more ▼]

De nombreux programmes thérapeutiques recommandent d’orienter la thérapie sur la reconnaissance du trouble ou de la maladie. Nous évoquerons cette problématique dans le cadre de la psychiatrie légale (particulièrement avec des patients présentant un diagnostic de schizophrénie et ayant commis des faits de délinquance sexuelle). Avoir pour objectif de réduire l’anosognosie pose la question des représentations du trouble et de la connaissance de ces phénomènes complexes. La distinction des perspectives en première et troisième personnes est un apport récent et décisif de la phénoménologie à la psychologie clinique et à la psychopathologie (Parnas, Sass & Zahavi, 2012). La perspective en troisième personne consiste en l’attribution, depuis une position externe, de signes cliniques repérés indépendamment du ressenti exprimé par le patient. L’exemple typique de ces signes est le délire et l’hallucination du schizophrène. Ces symptômes cristallisent précisément les difficultés qu’éprouve le sujet à se reconnaitre affecté du trouble. La perspective en première personne concentre, quant à elle, son attention sur l’expérience subjective exprimée par le patient. Si l’on reprend le cas de la schizophrénie, ce sont la « perte de l’évidence naturelle » des choses ou un « sentiment de diminution du soi » qui sont verbalisés. Ce pas de côté de la vision omnisciente du médical, assumant une remise en cause du pouvoir de domination qu’entraine la perspective en troisième personne, se révèle être un outil psychothérapeutique pertinent. Il désacralise le problème de l’anosognosie et ouvre la voie à une perspective intersubjective, à une « co-reconnaissance ». [less ▲]

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See detailDroit matériel de l'Union européenne - libertés de circulation et marché intérieur
Van Cleynenbreugel, Pieter ULg

Book published by Larcier (2017)

L'ouvrage introduit étudiants et praticiens aux fondements du droit du marché intérieur européen. L’analyse juridique se structure pédagogiquement autour des schémas de raisonnement simples et des ... [more ▼]

L'ouvrage introduit étudiants et praticiens aux fondements du droit du marché intérieur européen. L’analyse juridique se structure pédagogiquement autour des schémas de raisonnement simples et des tableaux récapitulatifs clairs. [less ▲]

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See detailElectro dynamic fragmentation of printed wiring boards as a preparation tool for their recycling
Martino, Rémi; Iseli, Cedric; Gaydardzhiev, Stoyan ULg et al

in Minerals Engineering (2017), 107

The use of Electro Dynamic Fragmentation (EDF) enables selective fragmentation of materials through generating electrical discharges as a means of fracturing. Liberated materials can be thus processed ... [more ▼]

The use of Electro Dynamic Fragmentation (EDF) enables selective fragmentation of materials through generating electrical discharges as a means of fracturing. Liberated materials can be thus processed downstream in a more efficient way especially when value-added End-of-Life (EoL) electronic equipment is recycled. The aim of this study was to assess the benefits of the EDF technology towards processing of EoL printed wiring boards (PWBs) in view their recyclability. Printed wiring boards were comminuted using EDF at three different settings and with a hammer mill for comparative experiment. The products coming out were characterized by optical microscopy, SEM and liberation oriented leaching. Subsamples from the various EDF stages were inspected to investigate the progress of cracks and degree of copper layers exposure. The different energy levels used during the EDF processing have resulted in different degrees of PWBs damages, starting from components removal to entire structure perturbation and size reduction. EDF has resulted in generation of a lesser amount of fines, however the optimal approach in view energy efficient post-processing of the studied PWBs was the combination between single-stage EDF for components removal only with subsequent shredding of the depopulated boards. [less ▲]

Detailed reference viewed: 46 (13 ULg)