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

Book published by Pearson Education (2006)

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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)

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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)

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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)

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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 ▲]

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See detailPerformance et expérience esthétique : le régime contemporain (Rancière)
Hagelstein, Maud ULg

Conference (2014)

Le cadre de ce colloque repose sur le constat de la perte d’intensité de l’ancien système des Beaux-Arts ou en tout cas sur l’idée de sa réévaluation contemporaine – opérée à partir d’une attention accrue ... [more ▼]

Le cadre de ce colloque repose sur le constat de la perte d’intensité de l’ancien système des Beaux-Arts ou en tout cas sur l’idée de sa réévaluation contemporaine – opérée à partir d’une attention accrue à l’hétérogénéité des pratiques artistiques. Pourquoi mobiliser ici la figure de Rancière ? Pour la raison suivante : c’est l’un des philosophes actuels qui s’est encore donné la peine d’essayer de théoriser de manière inédite (et non moderniste ) la fin du régime traditionnel des Beaux-Arts (2ème régime). Les trois grands régimes de l’art sont chez Rancière des régimes de perception, d’identification et d’interprétation de l’art – c’est-à-dire des ensembles déterminés (culturellement et même historiquement déterminés – semble-t-il ) d’habitudes perceptives, de moyens pratiques et d’outils théoriques permettant de délimiter le champ des objets et/ou expériences artistiques. Le régime qui a contribué à engager une rupture irréversible avec le système traditionnel des Beaux-Arts (à savoir : le régime esthétique de l’art – qui affecte a priori les expériences artistiques contemporaines) se caractérise essentiellement chez Rancière par deux mouvements : (1) effacement des spécificités des arts (au profit d’une expérience sensible commune à tous les arts – qu’il faudra définir) ; (2) effacement des frontières qui séparent l’art de l’expérience ordinaire. [less ▲]

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See detailPerformance evaluation and X-ray dose quantification for various scanning protocols of the GE eXplore 120 micro-CT
Bretin, Florian ULg; Warnock, Geoffrey; Luxen, André ULg et al

in IEEE Transactions on Nuclear Science (2013), 60(5), 3235-3241

The aim of this study was to evaluate the performance of the General Electric eXplore 120 micro-CT regarding image quality and delivered dose of several protocols. Image quality (resolution, linearity ... [more ▼]

The aim of this study was to evaluate the performance of the General Electric eXplore 120 micro-CT regarding image quality and delivered dose of several protocols. Image quality (resolution, linearity, uniformity and geometric accuracy) was assessed using the vmCT phantom developed for the GE eXplore Ultra, the QRM low contrast and the QRM Bar Pattern Phantom. All dose measurements were performed using a mobileMOSFET dose verification system and the CTDI100 and the MSAD were determined with a custom built PMMA phantom. Additionally, in vivo scans in sacrificed rats with different weights were acquired to assess dose, contrast and resolution variation due to X-ray absorption in surrounding tissue. The spatial resolution was determined as between 95 and 138 μm with a geometric accuracy of 0.1%. The system has a highly linear response to the iodine concentrations (0.937 to 30 mg/ml) for all protocols. The calculated CTDI100 ranged from 20.15 to 56.79 mGy and the MSAD from 27.98 to 77.45 mGy. The results were confirmed by in vivo scans in rats with different weights and no impact of body weight on delivered dose could be observed. However, body weight had a slight impact on image contrast and resolution. [less ▲]

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See detailPerformance evaluation of an aqueous-silicone oil two-phase partitioning bioreactor using Rhodococcus erythropolis T902.1 to remove VOC from gaseous effluents.
Aldric, Jean-Marc ULg; Thonart, Philippe ULg

in Journal of Chemical Technology & Biotechnology (2008), 83

BACKGROUND: In the framework of biological processes used for waste gas treatment, the impact of the inoculum size on the start-up performance must be better evaluated. Moreover, only few studies have ... [more ▼]

BACKGROUND: In the framework of biological processes used for waste gas treatment, the impact of the inoculum size on the start-up performance must be better evaluated. Moreover, only few studies have studied the behaviour of elimination capacity and biomass viability in a two-phase partitioning bioreactor (TPPB) used for waste gas treatment. Lastly, the impact of ethanol as a cosubstrate remains misunderstood. RESULTS: Firstly, the results show that no benefit of the inoculation with a high cellular density (> 1.5 g.L-1) can be observed on start-up performances. Secondly, the TPPB was monitored during 38 days to characterise its behaviour for several operational conditions. The removal efficiency is kept at 63 % for an inlet concentration of 7g.Nm-3 isopropylbenzene (IPB) and at some times points reaches 92 % during an intermittent loading phase (10 h.day-1), which corresponds to an elimination capacity mean of 4.10-3 g.L-1.min-1 (240g.m-3react.h-1) for an IPB inlet load (IL) mean of 6.19.10-3 g.L-1min.-1 (390 g.m-3.h-1). At continuous IPB loading, the performances of TPPB fall but the biomass acclimation to this operational condition is shorter than five days. The biomass grows to approximately 10 g.L-1 but cellular viability strongly changes during experiment. It can be suggested an endorespiration phenomenon in the bioreactor. In present work, it is also shown a simultaneous degradation of IPB and ethanol suggesting that the ethanol improves the biodegradation without generating an oxygen depletion. CONCLUSION: The TPPB water-silicone oil, with ethanol as cosubstrate allows removing high inlet load of IPB during the 38 days experiment. [less ▲]

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See detailPerformance evaluation of methods for correcting ocular artifacts in electroencephalographic (EEG) recordings
Kirkove, Murielle ULg; François, Clémentine ULg; Libotte, Aurélie et al

Conference (2013, February)

The presence of ocular artifacts (OA) due to eye movements and eye blinks is a major problem for the analysis of electroencephalographic (EEG) recordings in most applications. A large variety of methods ... [more ▼]

The presence of ocular artifacts (OA) due to eye movements and eye blinks is a major problem for the analysis of electroencephalographic (EEG) recordings in most applications. A large variety of methods (algorithms) exist for detecting or/and correcting OA’s. We identified the most promising methods, implemented them, and compared their performance for correctly detecting the presence of OA’s. These methods are based on signal processing “tools” that can be classified into three categories: wavelet transform, adaptive filtering, and blind source separation. We evaluated the methods using EEG signals recorded from three healthy persons subjected to a driving task in a driving simulator. We performed a thorough comparison of the methods in terms of the usual performances measures (sensitivity, specificity, and ROC curves), using our own manual scoring of the recordings as ground truth. Our results show that methods based on adaptive filtering such as LMS and RLS appear to be the best to successfully identify OA’s in EEG recordings. [less ▲]

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See detailPerformance evaluation of microbead and ELISA assays for follicular G-CSF: a non-invasive biomarker of oocyte developmental competence for embryo implantation.
Lédée, N.; Munaut, Carine ULg; Serazin, Valerie et al

in Journal of Reproductive Immunology (2010), 86(2), 126-32

G-CSF in individual follicular fluids correlates with the potential of the corresponding embryo to result in a live birth after transfer in IVF. To evaluate the requirements for routine follicular fluid G ... [more ▼]

G-CSF in individual follicular fluids correlates with the potential of the corresponding embryo to result in a live birth after transfer in IVF. To evaluate the requirements for routine follicular fluid G-CSF quantification, we compared follicular fluid G-CSF measurements made with two multiplexed microbead assays purchased from Bio-Rad Laboratories and R&D Systems, and a commercial G-CSF ELISA (R&D Systems). Individual follicular fluids (n=139) associated with transferred embryos were analysed to determine cytokine profile and the fate of each transferred embryo was recorded. The effect of multiplexing as well as comparison of the respective performances of the microbead assay with a flow cytometry assay was explored. Multivariable logistic regression analysis was performed and receiver operating characteristic (ROC) analysis was used to determine the performance and sensitivity/specificity of each method for individual follicular fluids. Covariate factors known to influence IVF outcome such as age, serum oestradiol and embryo score were systematically integrated in each analysis. The quantification of follicular fluid G-CSF using microbead assay methodologies, but not ELISA, yielded results showing the utility of follicular fluid G-CSF as a biomarker predictive of a successful delivery (Au(roc): 0.77 [0.68-0.84] (p=0.003) and 0.75 [0.66-0.82] (p=0.004) for Bio-Rad and R&D Systems microbead assays respectively), whereas follicular fluid G-CSF values quantified by ELISA were not predictive (Au(roc):0.61 [0.52-0.70] p=0.84). Microbead assay and flow cytometry appeared similarly efficient for quantifying follicular fluid G-CSF and multiplex versus single-plex assays did not influence the reliability of quantification. [less ▲]

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See detailPerformance Evaluation of the GE eXplore CT 120 Micro-CT for Various Scanning Protocols
Bahri, Mohamed Ali ULg; Bretin, Florian ULg; Warnock, Geoffrey ULg et al

Poster (2012, November 03)

The aim of this study was to evaluate the performance of the General Electric (GE) eXplore CT 120 micro-CT using the same methodology and image quality assurance vmCT phantom developed for the GE eXplore ... [more ▼]

The aim of this study was to evaluate the performance of the General Electric (GE) eXplore CT 120 micro-CT using the same methodology and image quality assurance vmCT phantom developed for the GE eXplore Ultra. In addition, Quality assurance in Radiology and Medicine (QRM) low contrast and bar pattern phantoms were used. The phantoms were imaged using the six protocols regularly used in our laboratory (Fast scan 220 (P1) or 360 (P2): 70 kV, 32 mA, 220 or 360 views; Soft tissue fast scan (P3): 70 kV, 50 mA, 220 views, Soft tissue step & shoot (P4): 80 kV, 32 mA, 220 views; Low Noise (P5): 100 kV, 50 mA, 720 views and In Vivo Bone scan (P6): 100 kV, 50 mA, 360 views). Data were reconstructed with an isotropic voxel size of 100 µm (50 µm when protocol detector-binning was reduced to 2x2). The MTF obtained with the slanted edge and coil methods agreed very well. A 10% modulation transfer function (MTF) was observed in the range 3.6-4.8 mm-1 (P1&2 = 4.2; P3&4 = 4.8; P5 = 3.6 and P6 = 3.8), corresponding to 95-138 µm resolutions. The smallest bars visually observed on the QRM pattern phantom image were 100 µm. The geometric accuracy was better than 0.1%. A highly linear (R2 > 0.999) relationship between measured and expected CT numbers for both the CT number accuracy and linearity sections of the phantom was observed with a voltage dependent slope. A cupping effect was observed on the uniform slices. This effect was clearly highlighted by the uniformity-to-noise ratio (P1 = 0.58, P2&3&4 = 0.75, P5 = 1.35 and P6 = 2.74) especially for the low-noise protocols P5 and P6. The best low contrast discrimination was observed for P2 and P5 protocols. In conclusion the eXplore CT 120 achieved a resolution in the range 95-138 µm. It was found to be linear and geometrically accurate. The major difference between the protocols was the noise level which limits the detectability of low contrasts. [less ▲]

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See detailPerformance evaluation of the General Electric eXplore CT 120 micro-CT using the vmCT phantom.
Bahri, Mohamed Ali ULg; Warnock, Geoffrey ULg; Plenevaux, Alain ULg et al

in Nuclear Instruments & Methods in Physics Research Section A (2011), 648

The eXplore CT 120 is the latest generation micro-CT from General Electric. It is equipped with a high power tube and a flat panel detector. It allows high resolution and high contrast fast CT scanning of ... [more ▼]

The eXplore CT 120 is the latest generation micro-CT from General Electric. It is equipped with a high power tube and a flat panel detector. It allows high resolution and high contrast fast CT scanning of small animals. The aim of this study was to compare the performance of the eXplore CT 120 with the one of the eXplore Ultra, its predecessor for which the methodology using the vmCT phantom was already described [1]. The phantom was imaged using typical rat (fast scan or F) or mouse (in vivo bone scan or H) scanning protocols. With the slanted edge method, a 10% modulation transfer function (MTF) was observed at 4.4 (F) and 3.9-4.4 (H) mm-1 corresponding to 114 μm resolution. A fairly larger MTF was obtained with the coil method with the MTF for the thinnest coil (3.3 mm-1 ) equal to 0.32 (F) and 0.34 (H). The geometric accuracy was better than 0.3%. There was a highly linear (R2 > 0.999) relationship between measured and expected CT numbers for both the CT number accuracy and linearity sections of the phantom. A cupping effect was clearly seen on the uniform slices and the uniformity-to-noise ratio ranged from 0.52 (F) to 0.89 (H). The air CT number depended on the amount of polycarbonate surrounding the area where it was measured: a difference as high as approximately 200 HU was observed. This hindered the calibration of this scanner in HU. This is likely due to the absence of corrections for beam hardening and scatter in the reconstruction software. However in view of the high linearity of the system, the implementation of these corrections would allow a good quality calibration of the scanner in HU. In conclusion, the eXplore CT 120 achieved a better spatial resolution than the eXplore Ultra (based on previously reported specifications) and future software developments to include beam hardening and scatter corrections will make the new generation CT scanner even more promising. [less ▲]

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See detailPerformance expectations, personal resources and job resources: How to they predict work engagement?
Barbier, Marie; Hansez, Isabelle ULg; Chmiel, Nik et al

in European Journal of Work and Organizational Psychology (2013), 22(6), 750-762

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See detailPerformance increase of carbon dioxide refrigeration cycle with the addition of parallel compression economization
Bell, Ian ULg

in Proceedings of the 6th IIR Gustav Lorenzen Natural Working Fluids (2004, September)

In the future, it would be preferable to replace the halocarbon refrigerants with natural refrigerants like carbon dioxide, but there have been concerns over the use of carbon dioxide as a refrigerant due ... [more ▼]

In the future, it would be preferable to replace the halocarbon refrigerants with natural refrigerants like carbon dioxide, but there have been concerns over the use of carbon dioxide as a refrigerant due to its perceived inefficiency. It is possible to partially overcome this problem by the manipulation of the cylinders of the compressors used in the vapor compression refrigeration cycle. If some of the cylinders are used to compress vapor in a parallel compression system from an intermediary pressure, a refrigerating effect and COP greater than that of the system with all of the cylinders on suction can be achieved. An analytic model was created that allowed environmental and physical parameters to be altered. The investigations also included experimentation with the addition of superheat for the primary compression path, for which performance increases were noted for some operating conditions. The primary focus of the research was for the use of carbon dioxide in a standard air conditioning application. Accordingly, evaporation and condensation pressures were selected to correspond closely with evaporation and condensation temperatures for other refrigerants. Under the conditions used for the following research, superheating did not improve efficiency, and was not included. Physical limitations placed on the ratio of the suction cylinder swept volume to the economized cylinder swept volume suggest that building this economized compressor would be feasible. In fact, a standard reciprocating compressor could be altered such that 2 to 4 cylinders, depending on the volumetric ratio, are used for the economized path. The research demonstrates that under some conditions an economized carbon dioxide system outperforms a similar halocarbon system in terms of efficiency and capacity. In the end, this is the litmus test that proves that carbon dioxide can compete on the level with popular halocarbon refrigerants in this economized mode. [less ▲]

Detailed reference viewed: 35 (2 ULg)