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See detailAutomatic phase identification of smart meter measurement data
Olivier, Frédéric ULg; Ernst, Damien ULg; Fonteneau, Raphaël ULg

in Proc. of CIRED 2017 (2017, June)

This paper highlights the importance of the knowledge of the phase identification for the different measurement points inside a low-voltage distribution network. Besides considering existing solutions, we ... [more ▼]

This paper highlights the importance of the knowledge of the phase identification for the different measurement points inside a low-voltage distribution network. Besides considering existing solutions, we propose a novel method for identifying the phases of the measurement devices, based exclusively on voltage measurement correlation. It relies on graph theory and the notion of maximum spanning tree. It has been tested on a real Belgian LV network, first with simulated unbalanced voltage for which it managed to correctly identify the phases of all measurement points, second, on preliminary data from a real measurement campaign for which it shows encouraging results. [less ▲]

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See detailUsing electric vehicles as flexible resource in power systems: A case study in the Netherlands
Beltramo, Agnese; Julea, Andreea; Refa, Nazir et al

in Proceedings of the 14th International Conference on the European Energy Market (2017, June)

The European Union (EU) is actively encouraging member countries to phase out traditional oil-fuelled cars in cities in favour of Electric Vehicles (EV) as a solution for increasing efficiency ... [more ▼]

The European Union (EU) is actively encouraging member countries to phase out traditional oil-fuelled cars in cities in favour of Electric Vehicles (EV) as a solution for increasing efficiency, contributing to ensure security of supply, decrease CO2 emission and decrease local (especially urban) air pollution coming from the transport sector. With the increasing associated charging infrastructure deployment all over European countries, the demand coming from these technologies might impact the power system and potentially offer a source of flexibility through variable charging profiles and battery storage capacity options. In the recent years, the Dutch government has adopted several policy support mechanisms for EVs uptake, which made the Netherlands the country with the highest market share of electric cars in 2015 in the EU, and the second-highest share worldwide after Norway. This country is therefore a unique case study for the analysis of EVs charging demand and impact of the power sector. The recent uptake of EVs provides a significant amount of historical data regarding charging profiles, connection times or utilisation patterns pertaining this technology. This paper aims at exploiting such data to evaluate the current and future impact of electric vehicle deployment on the power system. To that end, historical data from 2015 are used in conjunction with the Dispa-SET model, a unit commitment and power dispatch model developed at the Joint Research Centre (JRC) of the European Commission. This aims at investigating the impact of Battery Electric Vehicle (BEV) charging demand on the current Dutch power system, under different hypotheses for BEV technology penetration and renewable energy deployment (i.e. wind and solar) in the country. In addition, looking at the entire connection periods when vehicles are plugged to the grid, the battery capacity connected to the system is estimated, based on commercial BEV battery characteristics. This total capacity is finally used as variable storage unit in the model, in order to investigate the impact that Vehicle to Grid (V2G) strategies could have on the optimal use of power resources available, with particular attention to Variable Renewable Energy (VRE). [less ▲]

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See detailPeriod–luminosity relations of fast-rotating B-type stars in the young open cluster NGC 3766
Saio, H.; Ekström, S.; Mowlavi, N. et al

in Monthly Notices of the Royal Astronomical Society (2017), 467(4), 3864-3873

We study the pulsational properties of rapidly rotating main-sequence B-type stars using linear non-adiabatic analysis of non-radial low-frequency modes taking into account the effect of rotation. We ... [more ▼]

We study the pulsational properties of rapidly rotating main-sequence B-type stars using linear non-adiabatic analysis of non-radial low-frequency modes taking into account the effect of rotation. We compare the properties of prograde sectoral g and retrograde r modes excited by the κ mechanism at the Fe opacity peak with the newly discovered period–luminosity relation that is obeyed by a group of fast-rotating B-type stars in the young open cluster NGC 3766. The observed relation consists of two sequences in the period versus magnitude diagram, at periods shorter than 0.5 d. We find that this property is consistent with similar period–luminosity relations predicted for excited sectoral prograde g modes of azimuthal orders m = −1 and −2 in fast-rotating stars along an isochrone. We further show that some of the rapidly rotating stars that have photometric variability with periods longer than a day may be caused by r-mode pulsation predicted to be excited in these stars. One fast-rotating star, in particular, shows both short and long periods that can be explained by the simultaneous excitation of g- and r-mode pulsations in models of fast-rotating stars. [less ▲]

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See detailSartre, héritier de Heidegger ? Quelques remarques à propos du circuit de l'ipséité dans "L'Être et le Néant".
Recchia, Fabio ULg

in Revista Ética e Filosofia Política (2017), 1

Dans le champ de la philosophie française contemporaine, la filiation philosophique entre Heidegger et Sartre continue de poser question à leurs successeurs. Faut-il concevoir le second comme le simple ... [more ▼]

Dans le champ de la philosophie française contemporaine, la filiation philosophique entre Heidegger et Sartre continue de poser question à leurs successeurs. Faut-il concevoir le second comme le simple promulgateur des doctrines phénoménologiques du premier ? dans quelle mesure, en effet, Sartre est-il l'héritier de la pensée heideggérienne ? Telle est la question que nous réexaminons dans notre texte en mobilisant un développement précis de L'Être et le Néant : la théorie du circuit de l'ipséité. Sur cette base nous mettons en évidence la manière dont l'ontologie phénoménologique nuance la pensée heideggérienne à partir de la philosophie de Bergson et l'anthropologie de Mauss - ouvrant ainsi la voie au projet des psychanalyses existentielles qui articule un dialogue entre la phénoménologie et les sciences sociales françaises autour du problème de la constitution de l'identité personnelle. [less ▲]

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See detailShallow water model with anisotropic porosity for flood modelling on Cartesian grids
Bruwier, Martin ULg; Archambeau, Pierre ULg; Erpicum, Sébastien ULg et al

Conference (2017, June)

Detailed topographic data have become widely available for inundation mapping. While the use of such high-resolution data enables the computation of flow variables at a fine scale, the computation time ... [more ▼]

Detailed topographic data have become widely available for inundation mapping. While the use of such high-resolution data enables the computation of flow variables at a fine scale, the computation time remains too high for many practical applications. In contrast, models solving the shallow-water equations with porosity provide a useful tool to improve the computational efficiency, while preserving to some extent the detailed topographic information through porosity parameters. In this study, we present a new model solving the fully dynamic shallow water equations with anisotropic porosity based on Cartesian grids. Using a Cartesian grid leads to specific challenges, particularly as regards the definition of the conveyance porosities at the cell edges. Moreover, the presented model is further improved by a merging method so as to increase the computational efficiency without affecting the overall accuracy. The performance of the model has been evaluated based on a wide range of test cases, which confirm the validity of the model and the benefits of such a modelling framework. [less ▲]

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See detailProfiling inferior left dorsal premotor cortex: when Area 55b meets Premotor Eye-Field
Genon, Sarah ULg; Reid, Andrew; Langner, Robert et al

Poster (2017, June)

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See detailA decision support tool for transient stability preventive control
Pertl, Michael; Weckesser, Johannes ULg; Rezkalla, Michel et al

in Electric Power Systems Research (2017), 147

The paper presents a decision support tool for transient stability preventive control contributing to increased situation awareness of control room operators by providing additional information about the ... [more ▼]

The paper presents a decision support tool for transient stability preventive control contributing to increased situation awareness of control room operators by providing additional information about the state of the power system in terms of transient stability. A time-domain approach is used to assess the transient stability for potentially critical faults. Potential critical fault locations are identified by a critical bus screening through analysis of pre-disturbance steady-state conditions. The identified buses are subject to a fast critical contingency screening determining the actual critical contingencies/buses. These two screenings aim at reducing the computational burden of the assessment, since only contingencies considered as critical are taken into account. The critical clearing times for the critical contingencies are determined. A preventive re-dispatch of generators to ensure a predefined minimum critical clearing time for faults at all buses is proposed, while costs are minimized. The results of the assessment are presented to the control room operator, who decides to accept the suggested dispatch or to repeat the assessment considering additional user-specific constraints. The effectiveness of the proposed method is demonstrated on a standard nine-bus and the New England test system. [less ▲]

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See detailNumerical modelling of micro-plasto-hydrodynamic lubrication in plane strip drawing
Carretta, Yves ULg; Bech, Jakob; Legrand, Nicolas et al

in Tribology International (2017), 110

This paper presents a new finite element model capable of predicting the onset of micro-plasto-hydrodynamic (MPH) lubrication and the amount of lubricant escaping from surface pockets in metal forming ... [more ▼]

This paper presents a new finite element model capable of predicting the onset of micro-plasto-hydrodynamic (MPH) lubrication and the amount of lubricant escaping from surface pockets in metal forming. The present approach is divided in two steps. First, a simulation at the macroscopic level is conducted. Then, a second simulation highlighting microscopic liquid lubrication mechanisms is achieved using boundary conditions provided by the first model. These fluid-structure interaction computations are made possible through the use of the Arbitrary Lagrangian Eulerian (ALE) formalism. The developed methodology is validated by comparison to experimental measurements conducted in plane strip drawing. The effect of physical parameters like the drawing speed, the die angle and the strip thickness reduction is investigated. The numerical results show good agreement with experiments. [less ▲]

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See detailLes limites de l’administration de la PCL - R à une population de sujets schizophrènes dans le contexte médico-légal
Englebert, Jérôme ULg; Matteucci, Marie; De Page, Louis et al

Poster (2017, May 31)

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See detailTime, preference and intensity: A contrastive study of rather (than) and eerder (dan)
Ghesquière, Lobke; Brems, Lieselotte ULg

Conference (2017, May 24)

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See detailThe renewed role of national authorities in Eurozone banking supervision and resolution : time to take a federal « commandeering » doctrine more seriously ?
Van Cleynenbreugel, Pieter ULg

Scientific conference (2017, May 22)

In this paper, I would like to compare the doctrine of « commandeering » as recognised in U.S. constitutional law with the approach taken by the EU institutions when setting up the ECB’s single ... [more ▼]

In this paper, I would like to compare the doctrine of « commandeering » as recognised in U.S. constitutional law with the approach taken by the EU institutions when setting up the ECB’s single supervisory mechanism and the banking resolution framework. Starting from the fact that national supervisory authorities play an important albeit subordinate role in the EU’s banking supervision setup, I use the U.S. federalism approach as a means to point out the legitimacy and democratic accountability dangers this approach creates. Highlighting those potential difficulties in the first part of my presentation/paper, I subsequently analyse to what extent a more explicit commandeering doctrine – as recognised in U.S. constitutional law – could help overcome those difficulties and what steps need to be taken in that regard. [less ▲]

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See detailLa reconnaissance de la maladie mentale : perspectives en troisième et en première personne
Englebert, Jérôme ULg

Conference (2017, May 20)

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 ... [more ▼]

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 les difficultés qu’éprouve le sujet à se reconnaitre affecté du trouble (l’anosognosie), et ce point est considéré par de nombreux modèles comme une cible thérapeutique prioritaire. Il est attendu que le patient adopte la position propre à son évaluateur, et externe à sa subjectivité intrinsèque. 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, un « trouble du sens commun » 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, co-construite. Nous constaterons que la reconnaissance de la maladie en troisième personne, à laquelle on intègre une considération de la perspective en première personne, permet au patient d’être partie prenante du processus thérapeutique. [less ▲]

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See detailSchizophrénie et psychopathie : Analyse des difficultés d’objectivation diagnostique à partir de la PCL-R
Matteucci, Marie; Englebert, Jérôme ULg; De Page, Louis et al

Poster (2017, May 20)

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See detailDu définitif sur du provisoire...
Englebert, Jérôme ULg; Follet, Valérie

Conference (2017, May 18)

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See detailRadiohead and Prog Rock
Delville, Michel ULg

Conference (2017, May 18)

Detailed reference viewed: 18 (0 ULg)
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See detailApplication of wavelet transforms to geosciences: Extraction of functional and frequential information
Deliège, Adrien ULg

Doctoral thesis (2017)

It is now well-known that there exist functions that are continuous but nowhere differentiable. Still, it appears that some of them are less “irregular” than others. The pointwise regularity of a function ... [more ▼]

It is now well-known that there exist functions that are continuous but nowhere differentiable. Still, it appears that some of them are less “irregular” than others. The pointwise regularity of a function can be characterized by its Hölder exponent at each point. For the sake of practicability, it is more appropriate to determine the “size” of the sets of points sharing a same exponent, through their Hausdorff measure. By doing so, one gets the multifractal spectrum of a function, which characterizes in particular its monofractal or multifractal nature. The first part of this work is based on the so-called “wavelet leaders method” (WLM), recently developed in the context of multifractal analysis, and aims at its application to concrete situations in geosciences. First, we present the WLM and we insist particularly on the major differences between theory and practice in its use and in the interpretation of the results. Then, we show that the WLM turns out to be an efficient tool for the analysis of Mars topography from a unidimensional and bidimensional point of view; the first approach allowing to recover information consistent with previous works, the second being new and highlighting some areas of interest on Mars. Then, we study the regularity of temperature signals related to various climate stations spread across Europe. In a first phase, we show that the WLM allows to detect a strong correlation with pressure anomalies. Then we show that the Hölder exponents obtained are directly linked to the underlying climate and we establish criteria that compare them with their climate characteristics as defined by the Köppen-Geiger classification. On the other hand, the continuous version of the wavelet transform (CWT), developed in the context of time-frequency analysis, is also studied in this work. The objective here is the determination of dominant periods and the extraction of the associated oscillating components that constitute a given signal. The CWT allows, unlike the Fourier transform, to obtain a representation in time and in frequency of the considered signal, which thus opens new research perspectives. Moreover, with a Morlet-like wavelet, a simple reconstruction formula can be used to extract components. Therefore, the second part of the manuscript presents the CWT and focuses mainly on the border effects inherent to this technique. We illustrate the advantages of the zero-padding and introduce an iterative method allowing to alleviate significantly reconstruction errors at the borders of the signals. Then, we study in detail the El Niño Southern Oscillation (ENSO) signal related to temperature anomalies in the Pacific Ocean and responsible for extreme climate events called El Niño (EN) and La Niña (LN). Through the CWT, we distinguish its main periods and we extract its dominant components, which reflect well-known geophysical mechanisms. A meticulous study of these components allows us to elaborate a forecasting algorithm for EN and LN events with lead times larger than one year, which is a much better performance than current models. After, we generalize the method used to extract components by developing a procedure that detects ridges in the CWT. The algorithm, called WIME (Wavelet-Induced Mode Extraction), is illustrated on several highly non-stationary examples. Its ability to recover target components from a given signal is tested and compared with the Empirical Mode Decomposition. It appears that WIME has a better adaptability in various situations. Finally, we show that WIME can be used in real-life cases such as an electrocardiogram and the ENSO signal. [less ▲]

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