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See detailPerformance comparison between JWST/MIRI+NIRCam & VLT/SPHERE for exoplanet detection
Hanot, Charles ULg

Scientific conference (2010, February)

Performance comparison between JWST/MIRI and VLT/SPHERE for exoplanet detection Charles Hanot, Olivier Absil, Anthony Boccaletti, Céline Cavarroc, Jean Surdej In the context of exoplanet detection, a ... [more ▼]

Performance comparison between JWST/MIRI and VLT/SPHERE for exoplanet detection Charles Hanot, Olivier Absil, Anthony Boccaletti, Céline Cavarroc, Jean Surdej In the context of exoplanet detection, a large majority of the 400 detected exoplanets have been found by indirect methods. Today, progress in the field of high contrast imaging has allowed direct images of several exoplanetary systems to be taken (cf. HR 8799, Fomalhaut). In the near future, several new instruments are going to dramatically improve our sensitivity to exoplanet detection. Among these, SPHERE ( Spectro Polarimetric High contrast Exoplanet REsearch ) at the VLT and MIRI ( Mid Infra-Red Instrument) onboard JWST will both be equipped with coronagraphs to reveal faint objects in the vicinity of nearby stars. In this paper, we make use of the most recent evolutionary models of young (sub-)stellar objects and exoplanets to derive their luminosities in order to compare the sensitivity of SPHERE to that of MIRI. From this comparison, we present a catalogue of targets which are particularly well suited for MIRI with possible detections of planets down to (sub-)Saturn masses. [less ▲]

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See detailPerformance comparison of four kinds of flat nonimaging Fresnel lenses made of polycarbonates and polymethyl methacrylate for concentrated photovoltaics
Languy, Fabian ULg; Habraken, Serge ULg

in Optics Letters (2011), 36(14), 2743-2745

Solar concentrators made of a single refractive primary optics are limited to a concentration ratio of about 1000× [Opt. Express19, A280 (2011)OPEXFF1094-408710.1364/OE.19.00A280], due only to ... [more ▼]

Solar concentrators made of a single refractive primary optics are limited to a concentration ratio of about 1000× [Opt. Express19, A280 (2011)OPEXFF1094-408710.1364/OE.19.00A280], due only to longitudinal chromatic aberration, while mirrors are limited to ∼46,000× by the angular size of the Sun. To reduce the chromatic aberration while keeping cost-effective systems for concentrated photovoltaics, a study of four different kinds of flat Fresnel doublets made of polycarbonates and polymethyl methacrylate is presented. It reveals that Fresnel doublets may have fewer optical losses than non-Fresnel doublets, with a lower lateral chromatic split allowing for even higher concentration ratio. [less ▲]

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See detailPerformance comparison of heating control strategies combining simulation and experimental results.
Kummert, M.; Andre, Philippe ULg; Argiriou, A.

(2005, August)

Different heating system controllers for passive solar buildings are compared on two different buildings. The performance criterion combines energy performance and thermal comfort using the "cost function ... [more ▼]

Different heating system controllers for passive solar buildings are compared on two different buildings. The performance criterion combines energy performance and thermal comfort using the "cost function" paradigm. The experimental facilities did not allow a direct experimental comparison by using two identical buildings. The controllers were implemented alternatively in one building and a performance comparison was obtained in two ways: first by identifying short periods that have similar driving variables (weather conditions and building occupancy) and comparing the experimental results obtained in both cases. The second method mixes experiments and simulation using a well-tuned model of the building and its occupants. This paper discusses the results obtained using the above methods and shows that both methods give consistent estimates of the difference between controllers, while the second method allows to extrapolate useful information from the limited data available. [less ▲]

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See detailPerformance Comparison of Hydronic Secondary Loop Heat Pump and Conventional Air-Source Heat Pump
Bell, Ian ULg; Braun, James

in International Refrigeration and Air Conditioning Conference at Purdue, July 16-19, 2012 (2012, July)

In residential heat pump systems, the motivation for secondary loop systems is to allow for the use of flammable or toxic refrigerants with lower global warming potentials than the currently employed HFC ... [more ▼]

In residential heat pump systems, the motivation for secondary loop systems is to allow for the use of flammable or toxic refrigerants with lower global warming potentials than the currently employed HFC refrigerants. The addition of radiant panels as integral building components (embedded in concrete at construction) is becoming more common. Combining the large surface area of the radiant panel and an efficient primary loop, the hydronic secondary loop heat pump system can greatly outperform the conventional air-to-air heat pump. The improvement in coefficient of performance is as much as 38% over the conventional air-to-air heat pump when the secondary loop hydronic system is employed. Due to the large area of the radiant panel, the condensing temperature of the primary loop for the hydronic secondary loop heat pump can be reduced by as much as 5°C at high ambient temperatures. [less ▲]

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See detailPerformance comparison of Multifactor Dimensionality Reduction: JVM vs. Native code
Chaichoompu, Kridsadakorn ULg; Kittitornkun, Surin; Tongsima, Sissades

in ITC-CSCC: International Technical Conference on Circuits Systems, Computers and Communications. 2006 (2006)

Multifactor Dimensionality Reduction (MDR) was originally developed to detect gene-gene interactions in the domain of human genetics. MDR algorithm collapses high-dimensional genetic data, into a single ... [more ▼]

Multifactor Dimensionality Reduction (MDR) was originally developed to detect gene-gene interactions in the domain of human genetics. MDR algorithm collapses high-dimensional genetic data, into a single dimension thus permitting interactions to be detected in relatively small sample sizes. To deal with the large volume of data, we demonstrate the experiment of MDR software which was written in Java programming language and compare with native method. We focus on execution time, memory usage and CPU usage and describe the results. [less ▲]

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See detailPerformance de Acacia Auriculiformis (Cunn. A.) dans le système agroforestier au Sud-Bénin
Fonton, H. N.; Claustriaux, Jean-Jacques ULg; Agbahungba, G.

in Annales des Sciences Agronomiques du Bénin (2002), 3(1), 65-79

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See detailLa performance de l'entreprise sociale : définitions et limites d'une évaluation monétaire
Mertens de Wilmars, Sybille ULg; Marée, Michel ULg

in Revue Internationale P.M.E. (2012), 25(3-4), 91-122

In a social enterprise, the notion of "performance" must be understood in a broader sense than the sole financial profitability. Because enterprises of this type pursue a social mission, whose completion ... [more ▼]

In a social enterprise, the notion of "performance" must be understood in a broader sense than the sole financial profitability. Because enterprises of this type pursue a social mission, whose completion generates collective impacts, one has to go beyond what is made possible by the sole market-based indicators. This requires to revise not only the very notion of production, but also the way in which the value of what is produced by the enterprise is measured. This is the task that the authors of the present article tackle, through building a definition of performance understood as "enlarged production" – a notion which they nevertheless define with accuracy. Whenever the notion of production is enlarged so as to take into account the impacts of the latter, the question of whether this approach is also operational unavoidably arises. In particular, one must ask oneself whether the impacts that one wants to include in an enlarged conception of production are measurable. By nature, these impacts are not taken into account by the market and measuring them sends back to the classical question of the evaluation of non-market goods. The authors draw up an inventory of the various techniques of monetary evaluation of the value of non-market goods and indicate whether these techniques are likely to lead to values that are relevant to evaluate the performance of a social enterprise. They illustrate their analysis by applying this grid of analysis to the methodology of social return on investment (SROI). Because of the theoretical limits of monetary evaluation, the authors conclude that works on performance evaluation based on multi-criteria analyses must be further pursued. [less ▲]

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See detailLa performance de l’Etat-providence européen. Quel enseignement pour la Belgique?
Lefebvre, Mathieu ULg; Perelman, Sergio ULg; Pestieau, Pierre ULg

in Regards Economiques (2011), 93

Dans ce numéro de Regards économiques, nous présentons une mesure multidimensionnelle de la performance des Etats- providence de l’Union européenne. Cette mesure permet de comparer la performance des pays ... [more ▼]

Dans ce numéro de Regards économiques, nous présentons une mesure multidimensionnelle de la performance des Etats- providence de l’Union européenne. Cette mesure permet de comparer la performance des pays de l’Europe des 15 avec celle des 12 nouveaux membres; elle donne aussi la possibilité de tester l’hypothèse d’un éventuel dumping social; enfin elle peut être utilisée pour mieux appréhender la performance de la protection sociale de la Belgique et de ses composantes régionales. [less ▲]

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See detailPerformance de Portefeuille
Bodson, Laurent ULg; Grandin, Pascal; Hübner, Georges ULg et al

Book published by Pearson - 2ème éd. (2010)

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See detailPerformance de portefeuille
Lambert, Marie ULg; Hübner, Georges ULg; Grandin, Pascal

Book published by Pearson Education (2006)

Detailed reference viewed: 46 (1 ULg)
See detailLa performance des entreprises publiques. Une question de propriété ou de concurrence?
Gathon, Henry-Jean ULg; Pestieau, Pierre ULg

in Bouin, Olivier; Morrisson, Christian (Eds.) Les prvatisations: Un état des lieux (1996)

Detailed reference viewed: 23 (1 ULg)
See detailPerformance des mortiers de ragréage en fonction du mode de préparation des bétons support
Wiertz, Jean; Darimont, Anne ULg

in colloque européen Lyon 8-9-10 septembre 1992 (1992, September)

Detailed reference viewed: 12 (0 ULg)
See detailPerformance Effects of Administrative Innovations in US State Governments: A Preliminary Report on IT Management Arrangements for e-Government Success
Markus, M. Lynne; Bui, Quang Neo; Jacobson, Dax D. et al

Scientific conference (2013, January)

The success of e-government is believed to depend in part on the organizational and institutional arrangements that governments enact for the management of their IT resources. This paper develops the ... [more ▼]

The success of e-government is believed to depend in part on the organizational and institutional arrangements that governments enact for the management of their IT resources. This paper develops the conceptualization of IT management arrangements by considering possible interactions between two dimensions — 1) the organization of IT activities and 2) the control over decisions about IT activities (also known as governance) — for each of two categories of IT activities — IT projects (such as website development) and IT services (such as the operation of networks). In addition, the paper provides preliminary empirical evidence obtained from applying this expanded conceptualization in the context of American state governments. Many states appear to employ centralization of IT activities to offset decentralization of IT control and vice versa. Consequently, neither dimension alone provides a good characterization of governmental IT management arrangements. These findings have the potential to enhance our understanding of the barriers to, and enablers of, e-government success. [less ▲]

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See detailPerformance énergétique des bâtiments résidentiels en Wallonie : Etude relative à la détermination de la consommation d'énergie primaire de référence
Hauglustaine, Jean-Marie ULg; Dupont, Géraldine ULg; Di Pietrantonio, M. et al

Report (2006)

Objects of the study: - To constitute a sample of representative buildings (individual residences and collectives), a fortnight; - To formulate Eréf, with for objective preserving ethics, varying the ... [more ▼]

Objects of the study: - To constitute a sample of representative buildings (individual residences and collectives), a fortnight; - To formulate Eréf, with for objective preserving ethics, varying the assumptions on the basis of a situation corresponding to the actual position (K55) worms of the more severe requirements; - To calculate and compare the level of consumption of primary energy € according to the Flemish approach and the proposal of FPMs; - To highlight the interests for the various actors from one or the other formulation. [less ▲]

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See detailPerformance et arts contemporains. L’œuvre en mouvement
Hagelstein, Maud ULg

Conference given outside the academic context (2008)

Detailed reference viewed: 7 (1 ULg)
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See detailPerformance et conceptualisation : quelle place dans l’évaluation des compétences professionnelles à utiliser un traitement de texte ?
Chenu, Florent ULg

in Travail et Apprentissage. Revue de Didactique professionnelle (2009), 4

L’article présente les premiers résultats d’une recherche menée sur l’évaluation des compétences professionnelles . Plus précisément, ces travaux s’inspirent d’un texte de Mayen (2003) dans lequel il ... [more ▼]

L’article présente les premiers résultats d’une recherche menée sur l’évaluation des compétences professionnelles . Plus précisément, ces travaux s’inspirent d’un texte de Mayen (2003) dans lequel il propose de prendre en compte des indicateurs basés sur la conceptualisation de l’action pour évaluer des compétences professionnelles. Le but de l’expérimentation est d’examiner quels liens existent entre performance et conceptualisation (explicitée) dans l’utilisation professionnelle d’un traitement de texte. Un dispositif a permis de rencontrer individuellement 32 personnes inscrites en formation professionnelle dans le domaine de la bureautique. Ces rencontres ont consisté en la réalisation de tâches de type professionnel, en la participation à un entretien d’explicitation à propos des raisonnements mis en œuvre dans le cadre ces tâches et en l’administration d’un test mesurant de manière décontextualisée la maîtrise des commandes et outils du traitement de texte utiles voire nécessaires pour agir efficacement par rapport à ces tâches. Les premiers résultats sont les suivants : 1. Les raisonnements repérés chez les personnes en formation ne semblent pas s’organiser comme d’autres travaux en didactique professionnelle décrivent qu’ils s’organisent chez des professionnels d’autres domaines. En effet, bien que le contenu des explicitations des sujets puisse être rapproché de « propositions tenues pour vraies sur le réel » (Vergnaud, 2002, p.20), on est loin de découvrir un système construit autour de concepts centraux organisant l’activité du sujet de manière globale. Ce n’est pas une esquisse de modèle opératif (Pastré, 2007, 2008a, 2008b) qui apparaît mais plutôt un éventail large de raisonnements, de principes, de règles relativement indépendants les uns des autres, pour décrire ou/et justifier des actions et des manipulations limitées. 2. Des catégories peuvent être établies pour caractériser les modes de raisonnements véhiculés relevés dans les explicitations des sujets rencontrés, notamment par rapport à leur degré de rationalité. Ce texte présente un premier contour de ces catégories. [less ▲]

Detailed reference viewed: 64 (13 ULg)