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See detailAthena+: The first Deep Universe X-ray Observatory
Barret, D.; Nandra, K.; Barcons, X. et al

in Cambresy, L.; Martins, F.; Nuss, E. (Eds.) et al SF2A-2013: Proceedings of the Annual meeting of the French Society of Astronomy and Astrophysics (2013, November 01)

The Advanced Telescope for High-energy Astrophysics (Athena+) is being proposed to ESA as the L2 mission (for a launch in 2028) and is specifically designed to answer two of the most pressing questions ... [more ▼]

The Advanced Telescope for High-energy Astrophysics (Athena+) is being proposed to ESA as the L2 mission (for a launch in 2028) and is specifically designed to answer two of the most pressing questions for astrophysics in the forthcoming decade: How did ordinary matter assemble into the large scale structures we see today? and how do black holes grow and shape the Universe? For addressing these two issues, Athena+ will provide transformational capabilities in terms of angular resolution, effective area, spectral resolution, grasp, that will make it the most powerful X-ray observatory ever flown. Such an observatory, when opened to the astronomical community, will be used for virtually all classes of astrophysical objects, from high-z gamma-ray bursts to the closest planets in our solar neighborhood. In this paper, we briefly review the core science objectives of Athena+, present the science requirements and the foreseen implementation of the mission, and illustrate its transformational capabilities compared to existing facilities. [less ▲]

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See detailUnveiling the mystery of Combined Heat & Power (cogeneration)
Verbruggen, Aviel; Dewallef, Pierre ULg; Quoilin, Sylvain ULg et al

in Energy (2013), 61

The article unveils the mystery of cogeneration. Cogeneration is an add-on or embedded activity in thermal power plants, with as merit the use of part or whole of their point source heat exhausts. EU's ... [more ▼]

The article unveils the mystery of cogeneration. Cogeneration is an add-on or embedded activity in thermal power plants, with as merit the use of part or whole of their point source heat exhausts. EU's talk of “high-efficiency cogeneration” is an unfounded transfer of responsibility from the hosting thermal power generation plant onto CHP (Combined Heat & Power) activity. The quality of a CHP activity is univocally defined by its design power-to-heat ratio σ, a tombstone parameter derived from the design characteristics of the power plant. A thermal power plant may house more than one cogeneration activity. Identifying σ requires positioning the bliss point in the electricity–heat production possibility set of the cogeneration activity. The bliss point is where after electric output is maximized, the sum of that output and the maximum recoverable quantity of heat occurs. Once CHP's mystery of virtual bliss points is unveiled, the proper σ are found. With known σ by CHP activity, the quantity of cogenerated electricity is reliably assessed as best indicator of cogeneration performance. Our analysis is applicable on all relevant thermal power cycles that host CHP activities, and illustrated with a numerical example. Our lean method is necessary and sufficient for proper CHP regulation. [less ▲]

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See detailThe Gaia astrophysical parameters inference system (Apsis). Pre-launch description
Bailer-Jones, C. A. L.; Andrae, R.; Arcay, B. et al

in Astronomy and Astrophysics (2013), 559

The Gaia satellite will survey the entire celestial sphere down to 20th magnitude, obtaining astrometry, photometry, and low resolution spectrophotometry on one billion astronomical sources, plus radial ... [more ▼]

The Gaia satellite will survey the entire celestial sphere down to 20th magnitude, obtaining astrometry, photometry, and low resolution spectrophotometry on one billion astronomical sources, plus radial velocities for over one hundred million stars. Its main objective is to take a census of the stellar content of our Galaxy, with the goal of revealing its formation and evolution. Gaia's unique feature is the measurement of parallaxes and proper motions with hitherto unparalleled accuracy for many objects. As a survey, the physical properties of most of these objects are unknown. Here we describe the data analysis system put together by the Gaia consortium to classify these objects and to infer their astrophysical properties using the satellite's data. This system covers single stars, (unresolved) binary stars, quasars, and galaxies, all covering a wide parameter space. Multiple methods are used for many types of stars, producing multiple results for the end user according to different models and assumptions. Prior to its application to real Gaia data the accuracy of these methods cannot be assessed definitively. But as an example of the current performance, we can attain internal accuracies (RMS residuals) on F,G,K,M dwarfs and giants at G=15 (V=15-17) for a wide range of metallicites and interstellar extinctions of around 100K in effective temperature (Teff), 0.1mag in extinction (A0), 0.2dex in metallicity ([Fe/H]), and 0.25dex in surface gravity (logg). The accuracy is a strong function of the parameters themselves, varying by a factor of more than two up or down over this parameter range. After its launch in November 2013, Gaia will nominally observe for five years, during which the system we describe will continue to evolve in light of experience with the real data. [less ▲]

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See detailL'ULg met un TIGRE dans son moteur
Rauw, Grégor ULg; Nazé, Yaël ULg

Article for general public (2013)

Ciel (Le)

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See detailWASP-71b: a bloated hot Jupiter in an 2.9-day, prograde orbit around an evolved F8 star
Smith, A. M. S.; Anderson, D. R.; Bouchy, F. et al

in Astronomy and Astrophysics (2013), 552

We report the discovery by the WASP transit survey of a highly-irradiated, massive (2.242 +/- 0.080 MJup) planet which transits a bright (V = 10.6), evolved F8 star every 2.9 days. The planet, WASP-71b ... [more ▼]

We report the discovery by the WASP transit survey of a highly-irradiated, massive (2.242 +/- 0.080 MJup) planet which transits a bright (V = 10.6), evolved F8 star every 2.9 days. The planet, WASP-71b, is larger than Jupiter (1.46 +/- 0.13 RJup), but less dense (0.71 +/- 0.16 {\rho}Jup). We also report spectroscopic observations made during transit with the CORALIE spectrograph, which allow us to make a highly-significant detection of the Rossiter-McLaughlin effect. We determine the sky-projected angle between the stellar-spin and planetary-orbit axes to be {\lambda} = 20.1 +/- 9.7 degrees, i.e. the system is 'aligned', according to the widely-used alignment criteria that systems are regarded as misaligned only when {\lambda} is measured to be greater than 10 degrees with 3-{\sigma} confidence. WASP-71, with an effective temperature of 6059 +/- 98 K, therefore fits the previously observed pattern that only stars hotter than 6250 K are host to planets in misaligned orbits. We emphasise, however, that {\lambda} is merely the sky-projected obliquity angle; we are unable to determine whether the stellar-spin and planetary-orbit axes are misaligned along the line-of-sight. With a mass of 1.56 +/- 0.07 Msun, WASP-71 was previously hotter than 6250 K, and therefore might have been significantly misaligned in the past. If so, the planetary orbit has been realigned, presumably through tidal interactions with the cooling star's growing convective zone. [less ▲]

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See detailComet C/2012 S1 (Ison)
Lisse, C. M.; Wolk, S. J.; Christian, D. J. et al

in Central Bureau Electronic Telegrams (2013), 3719

CBET 3719 available at Central Bureau for Astronomical Telegrams.

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See detailComet C/2012 S1 (Ison)
Crovisier, J.; Colom, P.; Biver, N. et al

in Central Bureau Electronic Telegrams (2013), 3711

CBET 3711 available at Central Bureau for Astronomical Telegrams.

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See detailComet C/2012 S1 (Ison)
Opitom, Cyrielle ULg; Jehin, Emmanuel ULg; Manfroid, Jean ULg et al

in Central Bureau Electronic Telegrams (2013), 3693

CBET 3693 available at Central Bureau for Astronomical Telegrams.

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See detailDescription, Modeling and Simulation Results of a Test System for Voltage Stability Analysis
Van Cutsem, Thierry ULg; Papangelis, Lampros ULg

Report (2013)

This report details the models and the data of the so-called Nordic test system used by the Univ. of Liege team in several research works. The aim of the report is to make the data available to other ... [more ▼]

This report details the models and the data of the so-called Nordic test system used by the Univ. of Liege team in several research works. The aim of the report is to make the data available to other researchers active in the field. The report also includes a series of simulation results. [less ▲]

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See detailA new methodological approach for error distributions selection
Hambuckers, julien ULg; Heuchenne, Cédric ULg

Scientific conference (2013, November)

Since 2008 and its financial crisis, an increasing attention has been devoted to the selection of an adequate error distribution in risk models, in particular for Value-at-Risk (VaR) predictions. We ... [more ▼]

Since 2008 and its financial crisis, an increasing attention has been devoted to the selection of an adequate error distribution in risk models, in particular for Value-at-Risk (VaR) predictions. We propose a robust methodology to select the most appropriate error distribution candidate, in a classical multiplicative heteroscedastic model. In a first step, unlike to the traditional approach, we do not use any GARCH-type estimation of the conditional variance. Instead, we propose to use a recently developed nonparametric procedure: the Local Adaptive Volatility Estimation (LAVE). The motivation for using this method is to avoid a possible model misspecification for the conditional variance. In a second step, we suggest a set of estimation and model selection procedures tests based on the so-obtained residuals. These methods enable to assess the global fit of a given distribution as well as to focus on its behaviour in the tails. Finally, we illustrate our methodology on three time series (UBS stock returns, BOVESPA returns and EUR/USD exchange rates). [less ▲]

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See detailA. Adams; L. Alcott; E. Cady Stanton; K. Millett; Romans policiers EU, 19e et 20e; A. Walkezr
Dor, Juliette ULg

in Didier, Béatrice; Fouque, Antoinette; Calle-Gruber, Mireille (Ed.) Le dictionnaire universel des créatrices (2013)

Plusieurs notices du dictionnaire portant sur des écrivaines américaines des 19e et 20e siècles. Section dirigée par Adélaïde Russo.

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See detailA Remark on the Poroelastic Center of Dilation
Huynen, Alexandre ULg; Detournay, Emmanuel

in Journal of Elasticity (2013)

In the original derivation due to Dougall (1897), the center of dilation is constructed from the superposition of orthogonal force dipoles. However, it can also be built by combining dislocation dipoles ... [more ▼]

In the original derivation due to Dougall (1897), the center of dilation is constructed from the superposition of orthogonal force dipoles. However, it can also be built by combining dislocation dipoles. While the two representations are equivalent in elasticity, the different nature of the force and dislocation dipoles leads to different transient behaviors in poroelasticity, when the response evolves from undrained to drained. Indeed, we show that the poroelastic solution of a center of dilation is obtained by superposing the corresponding elastic solution and either an instantaneous fluid sink or an instantaneous fluid source, depending on whether the center of dilation is treated as a singular stress or displacement discontinuity. A simple explanation to the instantaneous injection or withdrawal of a finite volume of fluid from/to the singularity is given by adopting an exploded view of the poroelastic center of dilation. The exploration of the drained, undrained and transient responses of this singularity also requires to clarify the close relationship between an instantaneous fluid source and a continuous fluid dodecapole, an object constructed by collapsing onto a point three orthogonal pairs of fluid dipoles. [less ▲]

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See detailEncapsulation of water droplets on fibers
Weyer, Floriane ULg; Dreesen, Laurent ULg; Vandewalle, Nicolas ULg

Poster (2013, November)

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See detailDioxines en PCB’s in paling uit het Benedenrivierengebied
van Hattum, B; Nijssen, P; Focant, Jean-François ULg et al

Report (2013)

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See detailCraftwork, industry and art. ISIA (1922-1943) and the roots of Italian design education
Dellapiana, Elena; Prina, Daniela ULg

in Fallan, Kjetil; Lees-Maffei, Grace (Eds.) Made in Italy: Rethinking a Century of Italian Design (2013)

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See detailMolecular epidemiology of norovirus infections in symptomatic and and asymptomatic children from Bobo Dioulasso, Burkina Faso
HUYNEN, Pascale ULg; Mauroy, Axel ULg; Martin, Caroline et al

in Journal of Clinical Virology (2013), 58

Background: Noroviruses (NoV) are a leading cause of gastroenteritis worldwide. Few epidemiologicaldata regarding the NoV strains circulating in African countries are available.Objectives: To determine ... [more ▼]

Background: Noroviruses (NoV) are a leading cause of gastroenteritis worldwide. Few epidemiologicaldata regarding the NoV strains circulating in African countries are available.Objectives: To determine the prevalence of NoV in Bobo Dioulasso (Burkina Faso) in both symptomaticand asymptomatic gastroenteritis patients.Study design: Patients both with and without gastro-intestinal disorders were selected. Clinical andepidemiological data, as well as stool samples, were collected through March to April 2011.NoV molecular detection (genogrouping and genotyping) and viral load quantification were also per-formed for all samples.Results: NoV were detected in 22.2% of the 418 collected stool samples (21.2% and 24.8% from the 293symptomatic patients (SP) and the 125 asymptomatic patients (ASP) respectively).Genogroup (G) distribution was 7.5%, 10.2% and 3.4% for GI, GII and both GI/GII respectively among SPand 12.0%, 11.2% and 1.6% for GI, GII and both GI/GII, respectively, among ASP.Average viral load values were higher in SP than in ASP for GI (p = 0.03) but not for GII.Phylogenic analysis showed a high degree of genotype diversity in SP and ASP. One recombinantGII.7/GII.6 sequence was, to the best of our knowledge, detected for the first time.Conclusions: This study enabled identification of the specific molecular epidemiology of NoV strains cir-culating in a representative country in Eastern Africa, and additionally showed that ASP could play animportant “reservoir” role. A high strain diversity was detected with a surprisingly high proportion ofNoV GI compared to the common genotypes usually reported in comparable epidemiological studies. [less ▲]

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See detailAid for health in times of political unrest in Mali: Does donors' way of intervening allow protecting people's health?
Paul, Elisabeth ULg; Samaké, Salif; Berthé Issa Bara, Issa et al

in Health Policy & Planning (2013)

Mali has long been a leader in francophone Africa in developing systems aimed at improving aid effectiveness, especially in the health sector. But following the invasion of the Northern regions of the ... [more ▼]

Mali has long been a leader in francophone Africa in developing systems aimed at improving aid effectiveness, especially in the health sector. But following the invasion of the Northern regions of the country by terrorist groups and a coup in March 2012, donors suspended official development assistance, except for 20 support to NGOs and humanitarian assistance. They resumed aid after transfer of power to a civil government, but this was not done in a harmonized framework. This article describes and analyses how donors in the health sector reacted to the political unrest in Mali. It shows that despite its long sector-wide approach experience and international agreements to respect aid effectiveness principles, donors have not been able to intervene in view of safeguarding the investments of co-operation in the past decade, and of protecting the health systemss functioning. They reacted to the political unrest on a bilateral basis, stopped working with their ministerial partners, interrupted support to the health system which was still expected to serve populations needs and took months before organizing alternative and only partial solutions to resume aid to the health sector. The Malian example leads to a worrying conclusion: while protecting the health system's achievements and functioning for the population should be a priority, and while harmonizing donors' interventions seems the most appropriate way for that purpose, donors' management practices do not allow for reacting adequately in times of unrest. The article concludes by a number of recommendations. [less ▲]

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See detailCécile Laborde ou le républicanisme critique
Jacquemain, Marc ULg

in Politique : Revue de Débats (2013), 82

L'article présente le travail de Cécile Laborde relisant la querelle française du "hijab" à partir du républicanisme critique de Philippe Pettit. Le travail de Cécile Laborde, savant mais toujours lisible ... [more ▼]

L'article présente le travail de Cécile Laborde relisant la querelle française du "hijab" à partir du républicanisme critique de Philippe Pettit. Le travail de Cécile Laborde, savant mais toujours lisible, représente sans doute l'examen philosophique le plus poussé des travers du républicanisme à la française, utilisant judicieusement pour ce faire, les outils de la "Political Theory" anglo-saxonne. Elle examine les trois questions cruciales de la liberté religieuse, de l'égalité entre hommes et femmes et de la cohésion sociale d'une société. La thèse qui y est défendue est que le républicanisme à la française est lourdement paternaliste par sa prétention à définir, à la place des femmes ce qui constitue leur autonomie, et surtout par son déni de toute validité à la parole des femmes voilées. Cécile Laborde considère que les intuitions républicaines peuvent être dégagées de ce perfectionnisme répressif et qu'elles sont susceptibles alors de fournir une théorie normative parfaitement valide de l'autonomie. [less ▲]

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