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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 ▲]

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See detailPerformance Indicators Framework for Biodiversity Management in Gypsum Quarries Throughout Europe
Pitz, Carline ULg; Mahy, Grégory ULg; Marlet, Christine et al

Report (2013)

This study aims to establish a common Key Performance Indicators (KPIs) framework to report biodiversity for the Gypsum Industry at the European level. An original approach of participatory process has ... [more ▼]

This study aims to establish a common Key Performance Indicators (KPIs) framework to report biodiversity for the Gypsum Industry at the European level. An original approach of participatory process has been developed in order to integrate the different opinions and to reach a consensus framework between different stakeholders’ groups: - Eurogypsum stakeholders - European and local authorities - Scientific panel : universities and consulting offices - European and local associations for the conservation of nature - Stakeholders from the mining sector The strategy is based on five main steps: (i) To Build a stakeholders’ network; (ii) To build a framework proposal to be submitted to stakeholders by selecting a maximum set of indicators based on the literature and reaching an agreement on indicators with Eurogypsum (Focus Group); (iii) Reaching a consensus framework with all the stakeholders and evaluating feasibility by a Delphi Policy survey, by the analysis of the EIAs of the Gypsum Industry and by visiting three European quarries; (iv) Final validation with Eurogypsum (meeting); (v) Creating indicators’ Factsheets and a Eurogyspum report to the destination of the public. The resulting framework contains eleven indicators which are the most acceptable set of indicators for all the stakeholders. It answers to European legislation and strategies for biodiversity. It is intended to improve sustainability in the quarries and to help managing biodiversity, to allow setting up of appropriate reporting systems. The aim is to maintain the biodiversity status of the gypsum quarries. It is a flexible framework adaptable given the local context of each gypsum quarry in order to prove if a No Net Loss has been reached at a quarry’s scale. [less ▲]

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See detailPerformance indicators in cardiac surgery--time for public release.
Kolh, Philippe ULg

in Interactive Cardiovascular and Thoracic Surgery (2011), 12(4), 589-90

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See detailPerformance Measurement in Belgian Hospitals : a state-of-the-art
Van Caillie, Didier ULg; Rouhana, Rima ULg; Santin, Sarah

Scientific conference (2007, April 03)

This communication proposes a global state-of-the-art around the central question : "How is performance measured and controlled in Belgian hospitals. As a first step in a global research project dedicated ... [more ▼]

This communication proposes a global state-of-the-art around the central question : "How is performance measured and controlled in Belgian hospitals. As a first step in a global research project dedicated to the use of Balanced ScoreCard in publics hospitals around the world, it is essentially focused on global economic aspects and on major macroeconomic statistics. [less ▲]

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See detailPerformance Measurements of the microPET FOCUS 120 for Iodine-124 Imaging
Taleb, Dounia ULg; Bahri, Mohamed Ali ULg; Seret, Alain ULg et al

in IEEE Transactions on Nuclear Science (2012), PP

This study aimed to evaluate the performance of the microPET FOCUS 120 for 124I in terms of counting rate capability and image quality using the NEMA NU 4-2008 methodology. Scanner sensitivity was ... [more ▼]

This study aimed to evaluate the performance of the microPET FOCUS 120 for 124I in terms of counting rate capability and image quality using the NEMA NU 4-2008 methodology. Scanner sensitivity was measured for 124I for comparison and reached 75 cps/kBq, respectively, with the usual 350-650 keV energy window (EW) and 6 ns time window (TW). The noise equivalent count rate (NECR) index was defined as: NECR = RT2/(RP+RGP) (T = true, P = prompt, GP = γ-prompt). A rat phantom maximum NECR of 48 kcps was obtained for the 250-590 keV EW with 6 ns TW. An almost identical maximum NECR of 43 kcps was recorded for 350-590 and 350-650 keV EW and 6 ns TW. The 2 ns TW reduced the sensitivity and NECR by 40-50% for all EW. The mouse phantom NECR study was limited because of the maximum available activity concentration of 124I. The 250-590 keV EW showed the largest scatter and γ-prompt plus scatter fractions with 25.7% and 43%, respectively, for the rat phantom and 12.2% and 27% for the mouse phantom. With the 350-590 keV EW, these fractions decreased to 20% and 33.5% for the rat phantom and to 10% and 21% for the mouse phantom. The image quality was investigated with the NEMA NU 4-2008 dedicated phantom for four (two analytic and two iterative) 2D or 3D reconstruction methods. The lowest spillover ratios (SOR) for the phantom non-emitting regions were obtained for the 350-590 and 350-650 keV EWs. Recovery coefficients (RC) of the hot rods were the highest for the 350-590 keV EW except for the 1 mm rod. Scatter correction led to a large decrease in RC. The combination of the 350-590 keV EW with 6 ns TW appeared to be a good compromise between counting rate capability and image quality for the FOCUS 120, especially when maximum a posteriori reconstruction was used without scatter correction. Moreover this combination enabled the best quantification with an error as low as 0.36%. [less ▲]

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See detailPerformance modelling of peer-to-peer routing
Rai, I. A.; Brampton, A.; MacQuire, A. et al

in Parallel and Distributed Processing Symposium, 2007. IPDPS 2007. IEEE International (2007)

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See detailPerformance monitoring of an industrial boiler: classification of relevant variables with Random Forests
Sainlez, Matthieu ULg; Heyen, Georges ULg

in Pierucci, Sauro; Ferraris, Guido Buzzi (Eds.) 20th European Symposium on Computer Aided Process Engineering – ESCAPE20 (2010)

A data mining methodology, the random forests, is applied to analyze pollutant emission from the recovery boiler of a Kraft pulping process. Starting from a large database of raw process data, the goal is ... [more ▼]

A data mining methodology, the random forests, is applied to analyze pollutant emission from the recovery boiler of a Kraft pulping process. Starting from a large database of raw process data, the goal is to identify the input variables that explain the most output variations. [less ▲]

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See detailPerformance Monitoring Systems in Healthcare Organizations The Managerial Perception of Uncertainty in Volatile Environments
Rouhana, Rima; Van Caillie, Didier ULg

in IAMB (Ed.) Proceedings of the 10th IAMB Conference - "Management Challenges in Global Economy" (2011, June)

Monitoring performance in healthcare organizations appears evolving drastically over time, due to a continuous search for better quality, efficiency and timeliness. As a result, the usefulness of ... [more ▼]

Monitoring performance in healthcare organizations appears evolving drastically over time, due to a continuous search for better quality, efficiency and timeliness. As a result, the usefulness of traditional management/performance control systems in such organizations is questioned and a focus is then made on the context in which each organization is operating. In a contingent-based perspective, a limited number of qualitative and quantitative empirical studies examine how some major contingent variables (nature of the organization, size, structure…) influence both the managerial decision-making process and the management control process in healthcare organizations. But, while largely integrated in other managerial contexts (Kabwigiri and Van Caillie, 2000), most of them ignore the variable “uncertainty” and how uncertainty is perceived by managers in healthcare organizations. So, the prime interest of our empirical study is to appraise how uncertainty is appraised by managers in volatile environments. To investigate this subject further, we rely on seminal studies that link between the influence of the organizational attributes (structure, size, level of technology), and their effect on the managerial decisions-making (personal profile and perception) of a suitable management control system (MCS). Our methodology rests on a “qualitative comparative approach” of thirty case studies, lead in two heterogeneous environments (Belgium and Lebanon). Such method allows us to validate our theoretical framework with qualitative case studies collected via semi-structured questionnaire. Our findings provide us with a dialogue between a single (in-depth) case study exploring the phenomenon and a qualitative comparative approach. Thus, we gain understanding of the causal mechanisms and processes, as well as of the core determinants of the healthcare managerial adoption of performance monitoring systems (PMS). [less ▲]

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