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See detailHydrogeological conditions required for Underground Pumping Storage Hydroelectricity (UPSH) in old mines
Bodeux, Sarah ULg; Pujades, Estanislao ULg; Orban, Philippe ULg et al

in Abstract book (2016, January 26)

Renewable energy sources, because of their intermittence, could not afford a stable production and an adequate variability according to the energy demand. Underground Pumped Storage Hydroelectricity (UPSH ... [more ▼]

Renewable energy sources, because of their intermittence, could not afford a stable production and an adequate variability according to the energy demand. Underground Pumped Storage Hydroelectricity (UPSH) using abandoned mine works is an interesting alternative, in flat regions, to store energy during low demand periods by pumping water from an underground mine to an upper reservoir. From the hydrogeological point of view, two considerations can arise for studying the feasibility before constructing an UPSH plant: 1) the alteration of the natural conditions of surrounding aquifers, and (2) the efficiency of the plant depending on possible leakage in the cavities from the hydrogeological environment. A potential old slate mine was selected through a multi-criterion method and its geometrical and hydrogeological characteristics are used to build a simple but typical model. With the help of the HFEMC approach implemented in the code SUFT3D (HEG-ULg), the groundwater flows are modelled for a representative cavity. Simulations of groundwater flow induced by a UPSH system are performed and the main variables are identified. Piezometric heads around the reservoir oscillate, the magnitude of the oscillations and the time to achieve a pseudo-steady state (magnitude and head reached during oscillations not varying anymore with time) depend on the boundaries, the parameters of the aquifer and the characteristics of the underground reservoir. The required hydrogeological conditions are deduced and a screening methodology can be proposed to assess the main impacts caused in aquifers by UPSH plants. Their efficiency regarding the water level evolution inside the reservoir is also considered accommodating the cyclic pumped storage schemes. [less ▲]

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See detailHow heterogeneity of the K-field influences a heat plume in a shallow alluvial aquifer: responses from a heat tracer test
Klepikova, Maria; Jamin, Pierre ULg; Orban, Philippe ULg et al

in Abstract book (2016, January 26)

Simultaneous solute and heat tracer test provides essential information for a reliable assessment of low temperature geothermal systems. The actual efficiency of ‘open systems’, including heat storage ... [more ▼]

Simultaneous solute and heat tracer test provides essential information for a reliable assessment of low temperature geothermal systems. The actual efficiency of ‘open systems’, including heat storage projects, is strongly affected by the heterogeneity of the hydraulic conductivity field (K-field). It could be also useful for assessing the cumulative impacts of numerous projects in urban areas on the groundwater resources. Using field data from a solute and heat tracer test conducted in the alluvial aquifer of the Meuse River (Belgium), an inverse problem of parameter estimation is solved. The tracing experiment consisted in simultaneously injecting heated water and a dye tracer in a piezometer and monitoring the evolution of groundwater temperature and tracer concentration in the recovery well and in monitoring wells. To get insights in the 3D characteristics of the heat plume, an arrangement of three transects of observation wells was used. The breakthrough curves measured in the recovery well showed that heat transfer in the alluvial aquifer is slower and more dispersive than solute transport. Recovery is very low for heat while in the same time it is measured as relatively high for the solute tracer. This is due to the fact that heat transport is a thermal diffusion dominated process. For conditions corresponding to high Peclet numbers, the hydraulic conductivity is the primary calibration parameter for predicting heat plume distribution. Heat diffusion is larger than molecular diffusion, implying that exchange between groundwater and the porous medium matrix is far more significant for heat than for solute tracers. [less ▲]

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See detailLe notaire dans la régulation sociale des conflits violents dans la Principauté de Liège aux XVIIe et XVIIIe siècles
Drécourt, Aurore ULg

Conference (2016, January 26)

Les actes notariés constituent des sources d’une grande richesse pour l’historien et ont permis de nombreuses études. Inventaires, testaments, contrats de mariage sont autant de documents qui ont ... [more ▼]

Les actes notariés constituent des sources d’une grande richesse pour l’historien et ont permis de nombreuses études. Inventaires, testaments, contrats de mariage sont autant de documents qui ont renouvelé notre connaissance de la vie sociale et économique des populations d’autrefois. Toutefois, les actes réalisés par les notaires sont d’une telle variété qu’ils n’ont pas encore révélé tous leurs secrets. Glissés entre des centaines de documents à valeur économique, certains actes nous renseignent sur la violence de la société d’Ancien Régime et sur les solutions mises en œuvre pour la réguler. Ce genre d’étude s’est appuyé durant des décennies sur des archives judiciaires. Toutefois, il est de plus en plus acquis parmi les historiens de la justice que les populations d’Ancien Régime n’allaient pas systématiquement devant le juge pour régler leurs différends mais préféraient opter pour d’autres stratégies de résolutions de conflits. Le notaire a, à ce titre, joué un rôle majeur. Il est celui devant lequel on établit des accommodements. Il est aussi celui qui retranscrit et authentifie le récit subjectif des victimes, témoins ou agresseurs, qui seront ensuite, selon le choix du comparant, enregistrées ou non au greffe. Aussi l’étude des sources notariales offre-t-elle à l’historien la possibilité de saisir des récits qui ne seraient sans doute jamais parvenues à sa connaissance par la seule étude des archives criminelles. De plus, elles ont l’avantage de présenter des couches plus modestes de la population et de montrer que le judiciaire n’est pas la voie unique, voire préférée, pour régler les conflits. La présente communication propose de montrer toute la richesse de ces documents si peu étudiés par les historiens, le tout dans le cadre de la Principauté de Liège au XVIIe siècle. [less ▲]

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See detailContinuous Departure Time of Day Preferences for Continental U.S. Airline Markets Segmented by Distance, Direction of Travel, Number of Time Zones, Day of Week and Itinerary Type
Lurkin, Virginie ULg; Garrow, Laurie; Higgins, Matthew et al

E-print/Working paper (2016)

Airlines use itinerary choice models to allocate the total number of passengers in a city pair to specific itineraries. In a related paper, we estimated a multinomial logit (MNL) itinerary choice model ... [more ▼]

Airlines use itinerary choice models to allocate the total number of passengers in a city pair to specific itineraries. In a related paper, we estimated a multinomial logit (MNL) itinerary choice model using database of more than 3 million tickets for Continental U.S. markets provided by the Airlines Reporting Corporation that accounted for price endogeneity. The size and comprehensiveness of our database allowed us to estimate highly refined continuous departure time of day preference curves that account for distance, direction of travel, the number of time zones traversed, departure day of week and itinerary type (outbound, inbound or one-way). This paper and accompanying Excel spreadsheet located at http://garrowlab.ce.gatech.edu contain the results of all model coefficients (including the 1260 time of day parameters) and summarize results in a series of ten figures. These highly-refined time of day preference curves can be used by airlines, researchers, and government organizations in the evaluation of demand-management and other policies. [less ▲]

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Peer Reviewed
See detailAccounting for Price Endogeneity in Airline Itinerary Choice Models: An Application to Continental U.S. Markets
Lurkin, Virginie ULg; Garrow, Laurie; Higgins, Matthew et al

E-print/Working paper (2016)

Network planning models, which forecast the profitability of airline schedules, support many critical decisions, including equipment purchase decisions. Network planning models include an itinerary choice ... [more ▼]

Network planning models, which forecast the profitability of airline schedules, support many critical decisions, including equipment purchase decisions. Network planning models include an itinerary choice model which is used to allocate air total demand in a city pair to different itineraries. Multinomial logit (MNL) models are commonly used in practice and capture how individuals make trade-offs among different itinerary attributes; however, none that we are aware of account for price endogeneity. This study formulates an itinerary choice model that is consistent with those used by industry and corrects for price endogeneity using a control function that uses several types of instrumental variables. We estimate our models using database of more than 3 million tickets provided by the Airlines Reporting Corporation. Results based on Continental U.S. markets for May 2013 departures show that models that fail to account for price endogeneity overestimate customers’ value of time and result in biased price estimates and incorrect pricing recommendations. The size and comprehensiveness of our database allows us to estimate highly refined departure time of day preference curves that account for distance, direction of travel, the number of time zones traversed, departure day of week and itinerary type (outbound, inbound or one-way). These time of day preference curves can be used by airlines, researchers, and government organizations in the evaluation of different policies such as congestion pricing. [less ▲]

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See detailUn nouveau regard sur la tenture des Travaux d’Hercule de Marie de Hongrie (Patrimonio Nacional, série 23)
Laruelle, Anne-Sophie ULg

Conference (2016, January 26)

Les exploits d’Hercule suscitent depuis l’Antiquité de multiples interprétations et constituent l’un des thèmes littéraires et artistiques les plus appréciés à la Renaissance. Plus que toute autre figure ... [more ▼]

Les exploits d’Hercule suscitent depuis l’Antiquité de multiples interprétations et constituent l’un des thèmes littéraires et artistiques les plus appréciés à la Renaissance. Plus que toute autre figure antique, Hercule sert d’exemple aux souverains car il est considéré comme le modèle par excellence de la "vertu active". Ses Travaux sont l’une des sources d’inspiration majeures de la tapisserie flamande au XVIe siècle. Cette communication ambitionne d’apporter un nouvel éclairage sur la tenture en douze pièces achetée en 1535 par la régente des anciens Pays-Bas, Marie de Hongrie, à l’atelier bruxellois Dermoyen. Nous verrons que cette tenture connaît un véritable succès, qui conduit les ateliers flamands à réaliser de nombreuses rééditions jusqu’à la fin du siècle. Notre intervention, fondée sur une méthode déjà bien établie par les spécialistes de la tapisserie, s’articulera autour des quatre composantes principales de ce genre artistique : les pièces existantes et leur iconographie, la manufacture qui les a tissées, les artistes qui en ont fourni les modèles aux liciers, et enfin le commanditaire. [less ▲]

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See detailTailored made degradable synthetic polymers for 3D (bio)printing
Grandfils, Christian ULg

Conference (2016, January 26)

Detailed reference viewed: 22 (2 ULg)
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See detailTravail en laboratoire de niveau de confinement 2 (L2)
Grignet, Christine ULg

Conference (2016, January 26)

Detailed reference viewed: 6 (1 ULg)
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Peer Reviewed
See detailIdentités, préférences et attitudes des parlementaires envers le fédéralisme belge après la sixième réforme de l’État
Dodeigne, Jérémy ULg; Reuchamps, Min; Sinardet, Dave

in Courrier Hebdomadaire du CRISP (2016), 33

Detailed reference viewed: 15 (8 ULg)
See detailTreg, Th17 and γδ T cells during normal and abortive pregnancy
Polese, Barbara ULg; Gridelet, Virginie ULg; Munaut, Carine ULg et al

Poster (2016, January 25)

Detailed reference viewed: 19 (5 ULg)
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See detailTargeted and random mutagenesis of orphan GPCRs of the SREB family
Laschet, Céline ULg; Dupuis, Nadine ULg; Derj, Anouar ULg et al

Poster (2016, January 25)

Detailed reference viewed: 26 (0 ULg)
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See detailUnravelling the roles of lysine acetylation by Elp3 during inner ear development
Mateo Sanchez, Susana ULg; Delacroix, Laurence ULg; Freeman, Stephen ULg et al

Poster (2016, January 25)

We planned to investigate the role of Elp3 acetyl-transferase, a member of the Elongator complex, in inner ear formation. We first analysed the spatio-temporal pattern of Elp3 mRNA expression and showed ... [more ▼]

We planned to investigate the role of Elp3 acetyl-transferase, a member of the Elongator complex, in inner ear formation. We first analysed the spatio-temporal pattern of Elp3 mRNA expression and showed that it was expressed in the entire early otocyst at E11.5 and persisted later in the sensory epithelium of the cochlea, in the spiral ganglion and in the vestibule. To unravel functions of Elp3, we used conditional knock-out mice in which Elp3 gene is deleted from early otocyst (Elp3cKO). We submitted these mice to a battery of vestibular testing and found significant abnormalities. Besides, the auditory brain stem response of Elp3cKO indicated that these mice are severely deaf. We were also able to demonstrate an increased level of apoptosis in the Elp3cKO spiral ganglion leading to a reduced number of neurons and fibers innervating the sensory cells as well as a reduced number of their synaptic ribbons. Moreover, the remaining spiral ganglion neurons extend processes showing clearly defects regarding sensory cell innervation. In conclusion, our results clearly show a role for Elp3 both in hearing and balance. We plan to go deeper in the mechanisms involved through the identification of the proteins that are targeted for acetylation by Elp3. [less ▲]

Detailed reference viewed: 30 (5 ULg)