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See detailDevelopment of a unified model for flow-material interaction applied to porous charring ablators
Coheur, Joffrey ULg; Schrooyen, Pierre; Turchi, Alessandro et al

Conference (2017, June)

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See detailMagnetic Shielding Above 1 T at 20 K With Bulk, Large Grain YBCO Tubes Made by Buffer-aided Top Seeded Melt Growth
Wera, Laurent ULg; Fagnard, Jean-François ULg; Kumar, Numbury Devendra et al

in IEEE Transactions on Applied Superconductivity (2017), 27(4),

YBCO tubes of ~ 10 mm diameter closed at one extremity were engineered by a Buffer-Aided Top Seeded Melt Growth fabrication process (BA-TSMG). These tubes can act as efficient “dc” magnetic shields and ... [more ▼]

YBCO tubes of ~ 10 mm diameter closed at one extremity were engineered by a Buffer-Aided Top Seeded Melt Growth fabrication process (BA-TSMG). These tubes can act as efficient “dc” magnetic shields and are observed to reduce axial flux densities of 1.5 T by a factor of 100 at 20 K. Such performances are comparable in magnitude to the record threshold inductions reported for bulk MgB2 and Bi-2212 materials at lower temperatures. Magnetic shielding measurements for open and closed tubes at 77 K also show that the presence of the cap improves substantially the shielding performance at the closed extremity since it reduces the penetration through the open end. This fabrication technique is extremely promising for shielding “dc” stray fields generated by HTS magnets operated in a temperature range obtained by cryocoolers, liquid hydrogen (20 K) or liquid neon (27 K). [less ▲]

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See detailNumerical simulations of a non-charring ablator in high enthalpy flows by means of a unified flow-material solver
Schrooyen, Pierre; Coheur, Joffrey ULg; Turchi, Alessandro et al

Conference (2017, June)

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See detailL'Année sartrienne, n° 31
Cormann, Grégory ULg

Book published by Groupe d'Etudes Sartriennes (2017)

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See detailInsect fatty acids: A comparison of lipids from three Orthopterans and Tenebrio molitor L. larvae
Paul, Aman ULg; Frederich, Michel ULg; Caparros Megido, Rudy ULg et al

in Journal of Asia-Pacific Entomology (2017), 20(2), 337-340

In order to explore some potential insect sources of food lipids, the lipid compositions of three Orthopterans (Acheta domesticus, Conocephalus discolor and Chorthippus parallelus) were analyzed and ... [more ▼]

In order to explore some potential insect sources of food lipids, the lipid compositions of three Orthopterans (Acheta domesticus, Conocephalus discolor and Chorthippus parallelus) were analyzed and compared with those of Tenebrio molitor larvae. A. domesticus, Co. discolor, Ch. parallelus and T. molitor larvae were found to contain approximately 15%, 13%, 10% and 32% lipids on dry weight, respectively. The lipids from three Orthopterans contain much higher amounts of essential fatty acids than those of T. molitor larvae. The two Orthopterans of the suborder Ensifera i.e., A. domesticus and Co. discolor contain linoleic acid in major quantities, while Ch. parallelus of the suborder Caelifera, contain α-linolenic acid in major quantities. The consumption of linoleic and α-linolenic fatty acid is linked with numerous health promoting effects. The factors that contribute to differences in fatty acid profiles of these insects are being discussed. At last the nutritional parameters including polyunsaturated to saturated and omega 6 to omega 3 fatty acid ratios of these insect lipids are also being discussed to understand the potential role of these lipids in human nutrition. [less ▲]

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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 detailForeign Policy & International Development
Carlsen, Henrik; Pearson, Nakia ULg

in High-end Climate Change Policy Booklet (2017)

The conceptual framework for the chapter is based on the notion of “transnational climate impacts” (Benzie et al, 2016). By this we mean impacts that will require adaptation in the EU as a result of ... [more ▼]

The conceptual framework for the chapter is based on the notion of “transnational climate impacts” (Benzie et al, 2016). By this we mean impacts that will require adaptation in the EU as a result of climate change in other countries. [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 detailRegistered partnerships
Wautelet, Patrick ULg

in Basedow, Jürgen; Ferrari, Franco; de Miguel Asensio, Pedro (Eds.) et al EUROPEAN ENCYCLOPEDIA OF PRIVATE INTERNATIONAL LAW (2017)

This entry in the European Encyclopedia of Private International Law attempts to present the current state of the law in relation to registered partnerships. After an overview of the relevant sources ... [more ▼]

This entry in the European Encyclopedia of Private International Law attempts to present the current state of the law in relation to registered partnerships. After an overview of the relevant sources, attention is paid to the issue of characterization. The law applicable to the access to partnerships and effects of such partnerships is also covered. [less ▲]

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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 detailNew data on the Mesozoic radiation of chelonioids
Scavezzoni, Isaure ULg; Fischer, Valentin ULg

Poster (2017, June)

"Turtles" (Testudines) form a successful group of reptiles with several terrestrial, marine and fresh-water species. Their peculiar and somewhat constrained morphology (i. e. : carapace incorporating ribs ... [more ▼]

"Turtles" (Testudines) form a successful group of reptiles with several terrestrial, marine and fresh-water species. Their peculiar and somewhat constrained morphology (i. e. : carapace incorporating ribs, curved limbs, anapsid skull exempt of temporal fenestrae) and ecology has often obscured their relationships and, hence, their evolutionary history, notably in marine turtles (chelonioids). Modern chelonioids are divided in two clades (i. e. : shoft-shelled turtles and hard-shelled turtles) supported by distinct morphological and embryological characters. Their origin is traced back up to the Cretaceous, along with a series of extinct forms, many of which being collectively known as Protostegidae. Fossil evidence show that at least five clades of marine turtles were roaming the seas at the end of the Cretaceous. In fact, chelonioids appeared during the first stages of the Early Cretaceous and quickly exploded to reach a high level of disparity at the lowermost part of the late Cretaceous. Therefore, the Mesozoic radiation of chelonioids must have happened during the "middle" Cretaceous (especially the Aptian-Albian interval). However this radiation is poorly understood as the phylogenetic relationships of marine turtles are not resolved yet. Bringing new data may help resolve these issues, and it is the exact reason why the genus Rhinochelys is being investigated. [less ▲]

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See detailHic Sunt NATs: Uncovering Address Translation with a Smart Traceroute
Zullo, Raffaele; Pescapé, Antonio; Edeline, Korian ULg et al

in IEEE/IFIP Workshop on Mobile Network Measurement (MNM) (2017, June)

Middleboxes are pervasive in today's Internet as they are deployed for an increasing number of reasons. An example is the network address translation (NAT), one of the first task to be performed to cope ... [more ▼]

Middleboxes are pervasive in today's Internet as they are deployed for an increasing number of reasons. An example is the network address translation (NAT), one of the first task to be performed to cope with the lack of IPv4 addresses. Recently the landscape for NATs has become even more crowded, especially in mobile networks, mainly due to the impossibility of IPv6 to be a large-scale solution to addressing issues. In this paper, we present a novel methodology for detecting NATs embodied in Mobile Tracebox, a measurement tool for Android smart devices that detects a wide range of middleboxes. It analyzes ICMP time-exceeded messages received during \traceroute and points at IP and transport checksum inconsistencies in the embedded packets to uncover address translation along a path. We deployed Mobile Tracebox through a crowdsourcing approach and used the collected dataset to validate our methodology. Results showed that, in absence of middleboxes breaking \traceroute, it can help to detect and locate NATs in the majority of the cases. [less ▲]

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See detailTowards a Renewed Alias Resolution with Space Search Reduction and IP Fingerprinting
Grailet, Jean-François ULg; Donnet, Benoît ULg

in Network Traffic Measurement and Analysis Conference (TMA) (2017, June)

Since the early 2000's, the Internet Topology has been frequently described and modeled from the perspective of routers. To this end, alias resolution mechanisms have been developed in order to aggregate ... [more ▼]

Since the early 2000's, the Internet Topology has been frequently described and modeled from the perspective of routers. To this end, alias resolution mechanisms have been developed in order to aggregate all IP interfaces of a router, collected with traceroute, into a single identifier. So far, many active measurement techniques have been considered, often taking advantage of specific features from network protocols. However, a lot of these methods have seen their efficiency decrease over time due to security reinforcements across the Internet. In this paper, we introduce a generic methodology to conduct efficient and scalable alias resolution. It combines the space search reduction of TreeNET (a tool for efficiently discovering subnets) with a fingerprinting process used to assess the feasibility of several state-of-the-art alias resolution methods, using a small, fixed amount of probes. We validate our method along MIDAR on an academic groundtruth and demonstrate that our methodology can achieve similar accuracy while using less probes and discovering subnets in the process. We further evaluate our method with measurements made on PlanetLab towards several distinct ASes of varying sizes and roles in the Internet. The collected data shows that some properties of our fingerprints correlate with each other, hinting some observed profiles could be linked with equipment vendors. Both TreeNET (which implements our methodology) and our dataset are freely available. [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 detailMapping Soil Organic Carbon stocks and estimating uncertainties at the regional scale following a legacy sampling strategy (Southern Belgium, Wallonia)
Chartin, Caroline; Stevens, Antoine; Goidts, Esther et al

in Geoderma Regional (2017), 9

The quantification and the spatialisation of reliable SOC stocks (Mg C ha− 1) and total stock (Tg C) baselines and associated uncertainties are fundamental to detect the gains or losses in SOC, and to ... [more ▼]

The quantification and the spatialisation of reliable SOC stocks (Mg C ha− 1) and total stock (Tg C) baselines and associated uncertainties are fundamental to detect the gains or losses in SOC, and to locate sensitive areas with low SOC levels. Here, we aim to both quantify and spatialize SOC stocks at regional scale (southern Belgium) based on data from one non-design-based or model-based sampling scheme. To this end, we developed a computation procedure based on Digital Soil Mapping techniques and stochastic simulations (Monte-Carlo) allowing the estimation of multiple (here, 10,000) independent spatialized datasets. The computation of the prediction uncertainty accounts for the errors associated to both the estimations of i) SOC stocks and ii) parameters of the spatial model. Based on these 10,000 individuals, median SOC stocks and 90% prediction intervals were computed for each pixel, as well as total SOC stocks and their 90% prediction intervals for selected sub-areas and for the entire study area. Hence, a Generalised Additive Model (GAM) explaining 69.3% of the SOC stock variance was calibrated and then validated (R2 = 0.64). The model overestimated low SOC stock (below 50 Mg C ha− 1) and underestimated high SOC stock (especially those above 100 Mg C kg− 1). A positive gradient of SOC stock occurred from the northwest to the center of Wallonia with a slight decrease on the southernmost part, correlating to the evolution of precipitation and temperature (along with elevation) and dominant land use. At the catchment scale higher SOC stocks were predicted on valley bottoms, especially for poorly drained soils under grassland. Mean predicted SOC stocks for cropland and grassland in Wallonia were of 26.58 Tg C (SD 1.52) and 43.30 Tg C (2.93), respectively. The procedure developed here allowed to predict realistic spatial patterns of SOC stocks all over agricultural lands of southern Belgium and to produce reliable statistics of total SOC stocks for each of the 20 combinations of land use/agricultural regions of Wallonia. This procedure appears useful to produce soil maps as policy tools in conducting sustainable management at regional and national scales, and to compute statistics which comply with specific requirements of reporting activities. [less ▲]

Detailed reference viewed: 26 (6 ULg)