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See detailPerformance of vapor compression systems with compressor oil flooding and regeneration
Bell, Ian ULg; Groll, Eckhard; Braun, James

in International Journal of Refrigeration (2011), 34(1), 225233

Vapor compression refrigeration technology has seen great improvement over the last several decades in terms of cycle efficiency through a concerted effort of manufacturers, regulators, and research ... [more ▼]

Vapor compression refrigeration technology has seen great improvement over the last several decades in terms of cycle efficiency through a concerted effort of manufacturers, regulators, and research engineers. As the standard vapor compression systems approach practical limits, cycle modifications should be investigated to increase system efficiency and capacity. One possible means of increasing cycle efficiency is to flood the compressor with a large quantity of oil to achieve a quasi-isothermal compression process, in addition to using a regenerator to increase refrigerant subcooling. In theory, compressor flooding and regeneration can provide a significant increase in system efficiency over the standard vapor compression system. The effectiveness of compressor flooding and regeneration increases as the temperature lift of the system increases. Therefore, this technology is particularly well suited towards lower evaporating temperatures and high ambient temperatures as seen in supermarket refrigeration applications. While predicted increases in cycle efficiency are over 40% for supermarket refrigeration applications, this technology is still very beneficial for typical air-conditioning applications, for which improvements in cycle efficiency greater than 5% are predicted. It has to be noted though that the beneficial effects of compressor flooding can only be realized if a regenerator is used to exchange heat between the refrigerant vapor exiting the evaporator and the liquid exiting the condenser. [less ▲]

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See detailPerformance on a Computerized Shopping Task in Bipolar Disorder and Alcohol Dependency
Laloyaux, Julien ULg; Michel, Céline; Pellegrini, Nadia et al

Poster (2014, August 10)

Persons diagnosed with bipolar disorder and alcohol dependency are frequently subject to cognitive impairments and encounter difficulties during everyday life activities. However, little is known how ... [more ▼]

Persons diagnosed with bipolar disorder and alcohol dependency are frequently subject to cognitive impairments and encounter difficulties during everyday life activities. However, little is known how these deficits interact in real life. Moreover, previous studies have primarily used questionnaires or observational methods to assess everyday life functioning, both of which contain a number of limits. In order to address some of these limits, we developed a computerized real-life activity task, in particular, a shopping task where participants are required to shop for a list of 8 grocery store items in a virtual supermarket. Twenty individuals diagnosed with alcoholic dependence and 21 patients diagnosed with bipolar disorder were compared with healthy controls (20 and 21, respectively), matched for age, sex and educational level. All participants completed the shopping task, and both clinical groups were evaluated with an extensive battery of cognitive tests (assessing executive functioning, attention, processing speed and memory), clinical scales and a measure of real world functioning. Results showed that, for both clinical groups, performance on the computerized shopping task significantly differentiated patients and healthy controls for a number of variables, especially total time to complete the shopping task. Performances on shopping task variables, in both clinical groups, were also significantly correlated with cognitive tests measuring processing speed, episodic memory, cognitive flexibility and inhibition. Finally, performances on the computerized shopping task were significantly correlated with real world functioning in both patient groups. These findings suggest that the computerized task used in the present study provides a valid indication of the level of real world functioning for these clinical populations, and therefore may be viewed as a valuable instrument in both an evaluation and remediation context. [less ▲]

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See detailPerformance on a computerized shopping task significantly predicts real world functioning in persons diagnosed with bipolar disorder.
Laloyaux, Julien ULg; Pellegrini, Nadia; Mourad, Haitham et al

in Psychiatry Research (2013), 210(2), 465-471

Persons diagnosed with bipolar disorder often suffer from cognitive impairments. However, little is known concerning how these cognitive deficits impact their real world functioning. We developed a ... [more ▼]

Persons diagnosed with bipolar disorder often suffer from cognitive impairments. However, little is known concerning how these cognitive deficits impact their real world functioning. We developed a computerized real-life activity task, where participants are required to shop for a list of grocery store items. Twenty one individuals diagnosed with bipolar disorder and 21 matched healthy controls were administered the computerized shopping task. Moreover, the patient group was assessed with a battery of cognitive tests and clinical scales. Performance on the shopping task significantly differentiated patients and healthy controls for two variables: Total time to complete the shopping task and Mean time spent to consult the shopping list. Moreover, in the patient group, performance on these variables from the shopping task correlated significantly with cognitive functioning (i.e. processing speed, verbal episodic memory, planning, cognitive flexibility, and inhibition) and with clinical variables including duration of illness and real world functioning. Finally, variables from the shopping task were found to significantly explain 41% of real world functioning of patients diagnosed with bipolar disorder. These findings suggest that the shopping task provides a good indication of real world functioning and cognitive functioning of persons diagnosed with bipolar disorder. [less ▲]

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See detailPerformance on an everyday life activity in persons diagnosed with alcohol dependency compared to healthy controls: Relations between a computerized shopping task and cognitive and clinical variables.
Laloyaux, Julien ULg; Michel, Céline; Mourad, Haitham et al

in Alcohol & Alcoholism (2012), 47(3), 240-247

Aim: Persons diagnosed with alcohol dependency often suffer from cognitive impairments. Little is known, however, concerning how these cognitive deficits impact complex, everyday life activities. By this ... [more ▼]

Aim: Persons diagnosed with alcohol dependency often suffer from cognitive impairments. Little is known, however, concerning how these cognitive deficits impact complex, everyday life activities. By this experiment, we wished to contribute to a better characterization of the nature of everyday life difficulties in patients with alcohol dependency using a computerized shopping task. Methods: We developed a computerized real-life activity task (shopping task), where participants are required to shop for a list of 8 grocery store items. Twenty individuals diagnosed with alcohol dependency and 20 healthy controls were administered a battery of cognitive tests, clinical scales and the computerized shopping task. Results: Performance on the computerized shopping task significantly differentiated patients and healthy controls for several variables and in particular for Total time. Moreover, Total time to complete the task correlated significantly with several cognitive measures. In particular, poor performance on measures of processing speed, verbal episodic memory, cognitive flexibility and inhibition were significantly correlated with longer Total time. Finally, longer Total time was significantly correlated with poorer everyday life functioning and longer duration of illness. Conclusions: These findings suggest that the computerized task used in the present study is a good proxy measure of the level of everyday life and cognitive functioning of persons diagnosed with alcohol dependency. [less ▲]

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See detailPerformance relative des règles linéaire, quadratique et logistique en analyse discriminante
Glele Kakaï, R.; Palm, Rodolphe ULg

in XXXVIèmes Journées de Statistique (2004, May)

Monte Carlo study is achieved to compare linear, quadratic and logistic classification rules for two groups, in 480 situations related to the type of distribution, the overlap of the populations, the ... [more ▼]

Monte Carlo study is achieved to compare linear, quadratic and logistic classification rules for two groups, in 480 situations related to the type of distribution, the overlap of the populations, the number of variables, the sample size and the heteroscedasticity degree of the model, which is measured by a parameter gamma defined in the study. The results of this study show that the quadratic rule is the best only for severe heteroscedastic normal or moderate non-normal models with high overlap. The linear rule is the best for homoscedastic normal or moderate non-normal models with low overlap. The logistic rule is the best for severe non-normal models except when homoscedasticity occurs. In the order situations linear and logistic rules have almost the same performance. By considering the parameters computed on the data samples, the linear rule gives the best performance for high values of r whereas logistic rule performs is best for low or moderate values of the same parameter. [less ▲]

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See detailLa performance sociétale
Crutzen, Nathalie ULg

Article for general public (2010)

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See detailPerformance Study of an Overlay Approach to Active Routing in Ad Hoc Networks
Calomme, Sandrine; Leduc, Guy ULg

(2004, June)

We motivate the use of the active technology for routing in ad hoc networks. We present an active architecture where passive and active nodes can operate together, avoiding any change in the legacy muti ... [more ▼]

We motivate the use of the active technology for routing in ad hoc networks. We present an active architecture where passive and active nodes can operate together, avoiding any change in the legacy muti-hop routing protocol they use. We detail a basic reactive protocol which can be used to build any overlay on top of an ad hoc network. We model it as an active application called Re-Active Routing (RAR). RAR provides dynamic routing in dense and sparse active overlays. We investigate its performance in static and dynamic environments and show that it depends substantially on the active range, i.e. on the allowed maximal number of hops between two active nodes. For a well-chosen active range, RAR achieves good performance even if the mobility level is high and the overlay density is as low as 12.5 %. [less ▲]

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See detailPerformance study of ground-based infrared Bracewell interferometers. Application to the detection of exozodiacal dust disks with GENIE
Absil, Olivier ULg; den Hartog, R.; Gondoin, P. et al

in Astronomy and Astrophysics (2006), 448

Nulling interferometry, a powerful technique for high-resolution imaging of the close neighbourhood of bright astrophysical objets, is currently considered for future space missions such as Darwin or the ... [more ▼]

Nulling interferometry, a powerful technique for high-resolution imaging of the close neighbourhood of bright astrophysical objets, is currently considered for future space missions such as Darwin or the Terrestrial Planet Finder Interferometer (TPF-I), both aiming at Earth-like planet detection and characterization. Ground-based nulling interferometers are being studied for both technology demonstration and scientific preparation of the Darwin/TPF-I missions through a systematic survey of circumstellar dust disks around nearby stars. In this paper, we investigate the influence of atmospheric turbulence on the performance of ground-based nulling instruments, and deduce the major design guidelines for such instruments. End-to-end numerical simulations allow us to estimate the performance of the main subsystems and thereby the actual sensitivity of the nuller to faint exozodiacal disks. Particular attention is also given to the important question of stellar leakage calibration. This study is illustrated in the context of GENIE, the Ground-based European Nulling Interferometer Experiment, to be installed at the VLTI and working in the L' band. We estimate that this instrument will detect exozodiacal clouds as faint as about 50 times the Solar zodiacal cloud, thereby placing strong constraints on the acceptable targets for Darwin/TPF-I. [less ▲]

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See detailA performance study of RSVP with proposed extensions
Mathy, Laurent ULg; Hutchison, D.; Schmid, S. et al

in Computer Communications (2002), 25(18), 1782--1798

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See detailLa performance
Bawin, Julie ULg; Foulon, Pierre-Jean ULg

in Ligeia : Dossiers sur l'Art (2012), 117-120

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See detailPerformance, robustness and sensitivity analysis of the nonlinear tuned vibration absorber
Detroux, Thibaut ULg; Habib, Giuseppe ULg; Masset, Luc ULg et al

in Mechanical Systems & Signal Processing (2015), 60-61

The nonlinear tuned vibration absorber (NLTVA) is a recently developed nonlinear absorber which generalizes Den Hartog׳s equal peak method to nonlinear systems. If the purposeful introduction of ... [more ▼]

The nonlinear tuned vibration absorber (NLTVA) is a recently developed nonlinear absorber which generalizes Den Hartog׳s equal peak method to nonlinear systems. If the purposeful introduction of nonlinearity can enhance system performance, it can also give rise to adverse dynamical phenomena, including detached resonance curves and quasiperiodic regimes of motion. Through the combination of numerical continuation of periodic solutions, bifurcation detection and tracking, and global analysis, the present study identifies boundaries in the NLTVA parameter space delimiting safe, unsafe and unacceptable operations. The sensitivity of these boundaries to uncertainty in the NLTVA parameters is also investigated. [less ▲]

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See detailPerformance, slaughter characteristics and meat quality of young bulls from Belgian Blue, Limousin and Aberdeen Angus breeds fattened with a sugar-beet pulp or a cereal-based diet
Cuvelier, Christine ULg; Cabaraux, Jean-François ULg; Dufrasne, Isabelle ULg et al

in Animal Science (2006), 82(Part 1), 125-132

Thirty-six young fattening bulls from three breeds (Belgian Blue, Limousin and Aberdeen Angus) were fattened over 5 months with fattening diets based either on sugar-beet pulp or on cereals. Fattening ... [more ▼]

Thirty-six young fattening bulls from three breeds (Belgian Blue, Limousin and Aberdeen Angus) were fattened over 5 months with fattening diets based either on sugar-beet pulp or on cereals. Fattening performance as well as carcass and meat characteristics were measured. There were few relevant effects of the diets on the parameters. The breeds also showed similar fattening features. However, the BB had higher killing-out proportion and their carcasses presented better scores in terms of conformation and fattening. The meat quality of the breeds differed, especially in terms of luminosity, redness and cooking losses. There were also significant influences of breed on the chemical composition of meat; fat content was lowest in Belgian Blue and highest in Aberdeen Angus. Such specificities could help to allocate breeds in appropriate niches in Belgium. [less ▲]

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See detailPerformance-Based Aid: Why it will probably not meet promises
Paul, Elisabeth ULg

in Development Policy Review (2015), 33(3),

Performance-based aid (PBA) is increasingly advocated as a way to improve development aid effectiveness through resolving incentive issues inherent in aid relationships. Some donors use PBA together with ... [more ▼]

Performance-based aid (PBA) is increasingly advocated as a way to improve development aid effectiveness through resolving incentive issues inherent in aid relationships. Some donors use PBA together with performance-based financing arrangements within partner countries. Expectations from PBA are high – yet, while its rationale may look appealing, it is grounded on a restrictive model and flawed when taking account of real-world context. A number of problems associated to PBA have already been advanced as jeopardising its success. More fundamentally, one may question the mere appropriateness of PBA to provide incentives all along the chain from recipient governments to those who are supposed to produce results. Thus believing that PBA can have a mechanistic trickle-down incentive effect seems an illusion. [less ▲]

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See detailPerformance-based Approaches for high strength Tubular columns and connections under Earthquake and fire Loadings (ATTEL) - D4
Sommariva, Manuel; Maio, Daniele; Demonceau, Jean-François ULg et al

Report (2012)

Fire test data

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See detailPerformance-based financing for better quality of services in Rwandan health centres: 3-year experience.
Rusa, Louis; Ngirabega, Jean De Dieu; Janssen, Willy et al

in Tropical medicine & international health : TM & IH (2009), 14(7), 830-7

In 2005, the Ministry of Health in Rwanda, with the support of the Belgian Technical Cooperation, launched a strategy of performance-based financing (PBF) in a group of 74 health centres (HCs), covering 2 ... [more ▼]

In 2005, the Ministry of Health in Rwanda, with the support of the Belgian Technical Cooperation, launched a strategy of performance-based financing (PBF) in a group of 74 health centres (HCs), covering 2-m inhabitants. In 2006, PBF was extended to an additional group of 85 HCs, thus reaching 3.8-m inhabitants. This study evaluates the effect of PBF on HC performance from 2005 to 2007. Composite indicators for measuring quantity and quality of services were developed and evaluated through monthly formative supervisions by qualified and well-trained district supervisors. The strategy was based on a fixed fee per quality-approved service. The entire budget spent on the implementation of PBF amounted to $0.25/cap/year, of which $0.20/cap/year for subsidies and an estimated $0.05/cap/year for administration, supervision and training. A positive effect on utilization rates was only seen for activities that were previously less well organized; in this case, growth monitoring services and institutional deliveries. The quality of services, defined as the compliance rate with national and international norms, rose considerably for all services in both groups. A sustained level of quality between 80% and 95% was reached within 18 months in the first group. A similar result was reached in the second group in 8 months. [less ▲]

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See detailPerformances and limitations of the HRMS method for dioxins, furans and dioxin-like PCBs analysis in animal feedingstuffs Part I: Results of an inter-laboratory study
Eppe, Gauthier ULg; Cofino, W. P.; De Pauw, Edwin ULg

in Analytica Chimica Acta (2004), 519(2), 231-242

The European strategy for dioxin monitoring of the food chain has defined high-resolution gas chromatography coupled to high-resolution mass spectrometry (HRGC/HRMS) method as the confirmatory method that ... [more ▼]

The European strategy for dioxin monitoring of the food chain has defined high-resolution gas chromatography coupled to high-resolution mass spectrometry (HRGC/HRMS) method as the confirmatory method that can provide reliable and comparable results at sub-parts per trillion (ppt) level. This paper describes the first inter-laboratory study on dioxins, furans and dioxin-like PCBs by HRGC/HRMS method in animal feedingstuffs. Two different statistical approaches (ISO 5725 and Cofino's statistics) were used for the statistical evaluation. For this particular study, the performances of the HRGC/HRMS method seem to be congener-independent in repeatability and reproducibility conditions over a concentration range covering more than four orders of magnitude. Results clearly show the effect of precision loss below 0.1 ppt level per congener in repeatability conditions and below 0.2 ppt level per congener in reproducibility conditions. LODs reported by the laboratories give median values of 0.02 ng/kg for most of the toxic congeners. Relative standard deviation between the laboratories' mean values using upper-bound approach for TEQ calculation is 6.2%, more than twice the maximum level set at 0.75 ng TEQ/kg of product. (C) 2004 Elsevier B.V. All rights reserved. [less ▲]

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See detailPerformances and limitations of the HRMS method for dioxins, furans and dioxin-like PCBs analysis in animal feedingstuffs Part II: Does it comply with the European pro-active approach?
Eppe, Gauthier ULg; Maghuin-Rogister, Guy ULg; De Pauw, Edwin ULg

in Analytica Chimica Acta (2004), 519(2), 243-253

Based on the results obtained from the inter-laboratory study in Part 1, different approaches for detection and quantification limits are evaluated and discussed. An overview of the most commonly used ... [more ▼]

Based on the results obtained from the inter-laboratory study in Part 1, different approaches for detection and quantification limits are evaluated and discussed. An overview of the most commonly used concepts and terminologies in analytical chemistry is presented with the aim of establishing a link between them. Whatever the method used by laboratories for detection limit assessment, the median LOD value reported for the less chlorinated PCDD/Fs (i.e. 0.02 ng/kg) is in good agreement with the values recalculated using the inter-laboratory data. For LOQ the Eurachem approach based on a pre-established percentage of repeatability RSD appears to be. suitable. The study shows that a pre-established RSDr of 20% is recommended in order to achieve an acceptable LOQ of 0.05 ng/kg per congener. The 20% value seems to be sufficiently low to act tolerable RSD close to maximum limits. Furthermore, the repeatability and the reproducibility standard deviation against parts-per-trillion congener levels has been modeled by inverse first order functions. This congener precision model provides an interesting tool to subsequently assess the performances of the method in TEQ close to regulatory limits. Finally, the paper discusses two different ways of reporting and interpreting the results to assess compliance against statutory limits. (C) 2004 Elsevier B.V. All rights reserved. [less ▲]

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See detailPerformances d'un groupe de patients Alzheimer au Token Test
Ansay, C.; Van der Linden, Martial ULg

in Questions de Logopédie (1993), 27

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