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See detailComparaison des stratégies d’enseignement du basket-ball en milieu scolaire et en milieu sportif
Frédéric, Olivier ULg; Gribomont, Jérôme; Cloes, Marc ULg

in e Journal de la Recherche sur l'Intervention en Education Physique et Sport (2009), 16

Since many years, teamsports' teaching receives a special interest from researchers involved in the Sport Pedagogy domain. In parallel to the traditional approach focusing on sport skills teaching, other ... [more ▼]

Since many years, teamsports' teaching receives a special interest from researchers involved in the Sport Pedagogy domain. In parallel to the traditional approach focusing on sport skills teaching, other pedagogical processes more focused on learner and play are recommended today. If few data are available about how these sports are taught in school and sports contexts of the French speaking part of Belgium (Wallonia), we hypothesized that teamsports' teaching remains analytical whatever the context. To verify this hypothesis, we have video recorded basketball session proposed by physical education teachers/coaches. Using stimulated recall interviews, we compared the teaching strategies of both groups of subjects. Differences were observed in organisation as well as in didactic processes. However, similarities were identified in teaching content and interventions characteristics. [less ▲]

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See detailLa vitamine D : effets « classiques », « non classiques » et évaluation du statut du patient
Cavalier, Etienne ULg; Souberbielle, Jean-Claude

in Médecine Nucléaire : Imagerie Fonctionnelle et Métabolique (2009), 33

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See detailEvidence for wastewater influence in a low impacted area throughout stable isotope analyses of the limpet Patella caerulea and epilithic biofilms
Vermeulen, Simon ULg; Lepoint, Gilles ULg; Gobert, Sylvie ULg

Poster (2009, January)

Eutrophication is considered to be one of the main threats to marine environments leading to changes in trophic status of ecosystems and alteration of biological diversity. Carbon and Nitrogen stable ... [more ▼]

Eutrophication is considered to be one of the main threats to marine environments leading to changes in trophic status of ecosystems and alteration of biological diversity. Carbon and Nitrogen stable isotopes analyses were performed on the limpet Patella caerulea and one of its food sources (epilithic biofilms) to assess their potential as early indicators of eutrophication. Samples were seasonally collected in 2005-2006 on five locations gradually exposed to urban sewage in the Calvi Bay and in the Marseilles harbour. Stable isotope signatures of Patella caerulea muscles exhibited steady site - specific values over seasons. In contrast to this time – integrated signal, wide variations in biofilm values show that either composition or isotopic ratios of food sources may vary greatly in time and space. Elevated δ15N values of limpets and biofilms, typical of wastewater influence but unrelated to nitrogen loads, indicate the biological availability of sewage-derived nitrogen in the Calvi Bay and the Marseilles harbour. A reference level of δ15N values is rapidly reached with increasing depth that indicates the limited vertical extent of pollution in the Calvi Bay. [less ▲]

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See detailFish farm impacts on Posidonia oceanica meadows: interest of the microbenthic loop.
Pete, Dorothée ULg; Velimirov, Branko; Bouquegneau, Jean-Marie ULg et al

Poster (2009, January)

Posidonia oceanica, the seagrass endemic to the Mediterranean Sea, is a valuable tool to assess the environmental quality in coastal zones. However, only few studies have attempted to use characteristics ... [more ▼]

Posidonia oceanica, the seagrass endemic to the Mediterranean Sea, is a valuable tool to assess the environmental quality in coastal zones. However, only few studies have attempted to use characteristics of its sediment compartment as an indicator of environmental perturbations. In this study, the impact of a fish farm on the microbenthic loop (organic matter, bacteria, microphytobenthos and meiofauna) of P. oceanica meadows will be described. Samples were taken under an aquaculture situated in Calvi Bay (Corsica, France) at a depth of 22 m, in March and June 2008. The control site was the meadow situated in front of the research station STARESO (Calvi Bay, Corsica, France), sampled at the same periods and depth. Results concerning bacteria, microphytobenthos and organic matter will be presented here. For both seasons, differences between sites exist. For example, biomasses of organic matter, microphytobenthos and bacteria are higher in the fish farm than in the control site, indicating that the microbenthic loop has potential to be a good early indicator of pollution in this sea. [less ▲]

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See detailAnalyse des structures valorisant le rôle social du sport en Communauté Wallonie-Bruxelles
Vandermeulen, Mary ULg; Cloes, Marc ULg

in e Journal de la Recherche sur l'Intervention en Education Physique et Sport (2009), 16

En Belgique, la Fondation Roi Baudouin (FRB) est une référence en matière de développement du bien-être des citoyens. Dans la perspective de générer des informations utiles à la conception de son prochain ... [more ▼]

En Belgique, la Fondation Roi Baudouin (FRB) est une référence en matière de développement du bien-être des citoyens. Dans la perspective de générer des informations utiles à la conception de son prochain plan quinquennal, le Service Intervention et Gestion en Activités Physiques et Sportives (SIGAPS) de l’Université de Liège a été chargé de réaliser une étude prospective visant à identifier des pistes d’interventions originales susceptibles de rencontrer les besoins actuels des acteurs de terrain en « sport social ». La première étape de cette étude a porté sur l’établissement d’un état des lieux non exhaustif des initiatives utilisant le sport/l’activité physique comme outil social. Sur base des informations fournies par les acteurs de terrain, nous avons identifié les raisons justifiant le développement limité de ces dernières et les moyens qui devraient être mis en œuvre pour remédier à cette situation. Dans une deuxième étape, un groupe de praticiens s’est réuni en vue de faire émerger les pistes d’actions dans lesquelles la FRB pourrait s’investir afin de rencontrer les attentes réelles des spécialistes. Des propositions concrètes ont ainsi pu être formulées. Elles peuvent être considérées comme une source d’inspiration voire des recommandations. [less ▲]

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See detailGeometry and Symmetries in Coordination Control
Sarlette, Alain ULg

Doctoral thesis (2009)

The present dissertation studies specific issues related to the coordination of a set of “agents” evolving on a nonlinear manifold, more particularly a homogeneous manifold or a Lie group. The viewpoint is ... [more ▼]

The present dissertation studies specific issues related to the coordination of a set of “agents” evolving on a nonlinear manifold, more particularly a homogeneous manifold or a Lie group. The viewpoint is somewhere between control algorithm design and system analysis, as algorithms are derived from simple principles — often retrieving existing models — to highlight specific behaviors. With a fair amount of approximation, the objective of the dissertation can be summarized by the following question: Given a swarm of identical agents evolving on a nonlinear, nonconvex configuration space with high symmetry, how can you define specific collective behavior, and how can you design individual agent control laws to get a collective behavior, without introducing hierarchy nor external reference points that would break the symmetry of the configuration space? Maintaining the basic symmetries of the coordination problem lies at the heart of the contributions. The main focus is on the global geometric invariance of the configuration space. This contrasts with most existing work on coordination, where either the agents evolve on vector spaces — which, to some extent, can cover local behavior on manifolds — or coordination is coupled to external reference tracking such that the reference can serve as a beacon around which the geometry is distorted towards vector space-like properties. A second, more standard symmetry is to treat all agents identically. Another basic ingredient of the coordination problem that has important implications in this dissertation is the reduced agent interconnectivity: each agent only gets information from a limited set of other agents, which can be varying. In order to focus on issues related to geometry / symmetry and reduced interconnectivity, individual agent dynamics are drastically simplified to simple integrators. This is justified at a “planning” level. Making the step towards realistic dynamics is illustrated for the specific case of rigid body attitude synchronization. The main contributions of this dissertation are I. an extensive study of synchronization on the circle, (a) highlighting difficulties encountered for coordination and (b) proposing simple strategies to overcome these difficulties; II. (a) a geometric definition and related control law for “consensus” configurations on compact homogeneous manifolds, of which synchronization — all agents at the same point — is a special case, and (b) control laws to (almost) globally reach synchronization and “balancing”, its opposite, under general interconnectivity conditions; III. several propositions for rigid body attitude synchronization under mechanical dynamics; IV. a geometric framework for “coordinated motion” on Lie groups, (a) giving a geometric definition of coordinated motion and investigating its implications, and (b) providing systematic methods to design control laws for coordinated motion. Examples treated for illustration of the theoretical concepts are the circle S^1 (sometimes the sphere S^n ), the rotation group SO(n), the rigid-body motion groups SE(2) and SE(3) and the Grassmann manifolds Grass(p,n). The developments in this dissertation remain at a rather theoretical level; potential applications are briefly discussed. [less ▲]

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See detailDe « Un an au Front national » au prétoire
Grandjean, Geoffrey ULg

Article for general public (2009)

This article summarizes a book and tries to give a critical perspective on the research' methodology.

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See detailAntoine Garapon, Peut-on réparer l’histoire ? Colonisation, esclavage, Shoah, Paris, Odile Jacob, 2008, 287 p.
Grandjean, Geoffrey ULg

in Cahiers de Sciences Politiques de l'ULg (2009)

This article gives a summary of a book on restorative justice.

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See detailA Generalized Likelihood Ratio Test for Adaptive Gas Turbine Performance Monitoring
Borguet, Sébastien ULg; Léonard, Olivier ULg

in Journal of Engineering for Gas Turbines & Power (2009), 131(1),

Kalman filters are widely used in the turbine engine community for health monitoring purposes. This algorithm has proven its capability to track gradual deterioration with good accuracy. On the other hand ... [more ▼]

Kalman filters are widely used in the turbine engine community for health monitoring purposes. This algorithm has proven its capability to track gradual deterioration with good accuracy. On the other hand, its response to rapid deterioration is a long delay in recognizing the fault and/or a spread of the estimated fault on several components. The main reason for this deficiency lies in the transition model of the parameters that is blended in the Kalman filter and assumes a smooth evolution of the engine condition. This contribution reports the development of an adaptive diagnosis tool that combines a Kalman filter and a secondary system that monitors the residuals. This auxiliary component implements a generalized likelihood ratio test in order to detect and estimate all abrupt fault. The enhancement in terms of accuracy and reactivity brought by this adaptive Kalman filter is highlighted for a variety of simulated fault cases that may be encountered on a commercial aircraft engine. [DOI: 10.1115/1.2967493] [less ▲]

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See detailPALETTE: Analysis of Instrumental Genesis lived by the CoPs
Daele, Amaury; Charlier, Bernadette; Ciussi, Mélanie et al

Report (2009)

The research presented in this deliverable aimed at observing and analysing the use of PALETTE services in authentic CoP contexts. We first present our conceptual framework based on the instrumental ... [more ▼]

The research presented in this deliverable aimed at observing and analysing the use of PALETTE services in authentic CoP contexts. We first present our conceptual framework based on the instrumental genesis theory. We then present our methodology for the generation of data and the analysis. Seven cases of design in use of PALETTE services and scenarios by CoPs are then described and analysed. In the discussion section, we carry out a cross-case analysis aiming at highlighting the common conditions of use of the services through the seven analysed cases. This discussion provides reflection that may inform the use of PALETTE services by other CoPs in other contexts. Finally, in the conclusion, we reflect on our methodological approach and results, and provide guidelines for further research. [less ▲]

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See detailLe cas clinique du mois. Osteogenesis imperfecta
Kaux, Jean-François ULg; Le Goff, Caroline ULg; Debray, François-Guillaume ULg et al

in Revue Médicale de Liège (2009)

We report the case of a young boy who had had multiple bone fractures (more than 10) since the age of 19 months. The father had the same clinical history. The clinical examination was normal for his age ... [more ▼]

We report the case of a young boy who had had multiple bone fractures (more than 10) since the age of 19 months. The father had the same clinical history. The clinical examination was normal for his age except blue sclera. The bone densitometry showed a severe osteoporosis for his age. Biological exam swere correct. The genetic exploration revealed mutation of COL1A2 gene. With this clinical history, the diagnosis of Osteogenesis imperfecta (OI) was retained. OI is a hereditary dystrophy with abnormal synthesis or metabolism of collagen with, often, mutation of COL1A1 or COL1A2 genes. There are 7 different forms. We consider the possible differential diagnoses. The goal of any treatment is to promote bone remineralisation and to decrease the fracture frequency. The treatment includes calcium and vitamin D, and in the presence of some precise criteria, biphosphonate therapy. [less ▲]

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See detailWeekly satellite sea surface temperature around Corsica, a DINEOF analysis of AVHRR data (1998), foreseeing comparison with interpolated and modelled fields.
Sirjacobs, Damien ULg; Lenartz, Fabian ULg; Troupin, Charles ULg et al

Poster (2009, January)

Providing wide coverage and high spatio-temporal resolution, SST satellite archives are valuable sources of information for sound understanding of the ocean dynamics, including validation of ... [more ▼]

Providing wide coverage and high spatio-temporal resolution, SST satellite archives are valuable sources of information for sound understanding of the ocean dynamics, including validation of hydrodynamical modelling studies. Yet original SST fields have also many gaps (clouds, retrieval problems), but they are known to exhibit strong spatial and temporal correlations for regions of similar dynamics. This is exploited by the parameter free statistical technique DINEOF (Data Interpolation with Empirical Orthogonal Functions) [Alvera-Azcárate et al. (2005) Ocean Modell.; Beckers et al. (2006) Ocean Sciences] to produce full weekly analysis of the variability of the sea surface temperature (SST) around Corsica and in the Ligurian Sea at weekly temporal resolution during the year 1998. A detection of outliers implemented in DINEOF analysis is tested for pointing out unusual or invalid SST data. This study is realised foreseeing a comparison of DINEOF weekly averaged reconstructed fields with those obtained by interpolating methods on the same dataset (Data Interpolating Variationnal Analysis and Optimal Interpolation schemes), and with outputs of an implementation of the GHER 3D model in this area. [less ▲]

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See detailSensitivity analysis of prior model probabilities and the value of prior knowledge in the assessment of conceptual model uncertainty in groundwater modelling
Rojas, Rodrigo; Feyen, Luc; Dassargues, Alain ULg

in Hydrological Processes (2009), 23

A key point in the application of multi-model Bayesian averaging techniques to assess the predictive uncertainty in groundwater modelling applications is the definition of prior model probabilities, which ... [more ▼]

A key point in the application of multi-model Bayesian averaging techniques to assess the predictive uncertainty in groundwater modelling applications is the definition of prior model probabilities, which reflect the prior perception about the plausibility of alternative models. In this work the influence of prior knowledge and prior model probabilities on posterior model probabilities, multi-model predictions, and conceptual model uncertainty estimations is analysed. The sensitivity to prior model probabilities is assessed using an extensive numerical analysis in which the prior probability space of a set of plausible conceptualizations is discretized to obtain a large ensemble of possible combinations of prior model probabilities. Additionally, the value of prior knowledge about alternative models in reducing conceptual model uncertainty is assessed by considering three example knowledge states, expressed as quantitative relations among the alternative models. A constrained maximum entropy approach is used to find the set of prior model probabilities that correspond to the different prior knowledge states. For illustrative purposes, a three-dimensional hypothetical setup approximated by seven alternative conceptual models is employed. Results show that posterior model probabilities, leading moments of the predictive distributions and estimations of conceptual model uncertainty are very sensitive to prior model probabilities, indicating the relevance of selecting proper prior probabilities. Additionally, including proper prior knowledge improves the predictive performance of the multi-model approach, expressed by reductions of the multi-model prediction variances by up to 60% compared with a non-informative case. However, the ratio between-model to total variance does not substantially decrease. This suggests that the contribution of conceptual model uncertainty to the total variance cannot be further reduced based only on prior knowledge about the plausibility of alternative models. These results advocate including proper prior knowledge about alternative conceptualizations in combination with extra conditioning data to further reduce conceptual model uncertainty in groundwater modelling predictions. [less ▲]

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See detailChemical and enzymatical modifications of sugar derived from lignocellulose
Richard, Gaetan ULg; Laurent, Pascal ULg; Nott, Katherine ULg et al

Poster (2009, January)

Actually, biorefinery is increasingly considered as a promising alternative to petroleum chemistry, since it aims at not only the replacement of fossil energy but also the development of chemicals from ... [more ▼]

Actually, biorefinery is increasingly considered as a promising alternative to petroleum chemistry, since it aims at not only the replacement of fossil energy but also the development of chemicals from biomass, with applications such as detergents, phytopharmaceutics, solvents, plastics, etc. The valorisation of carbohydrates from renewable raw materials is currently the subject of numerous researches. In this context, the synthesis of new surfactants derived from the sugars issued from the lignocellulose hydrolysis was undertaken by chemical or enzymatic routes. In this poster, the examples of glucose, cellobiose and uronic acids will be discussed. Whatever the way used, the reaction conditions (use of a catalyst, protection/deprotection steps, type of solvent, presence of co-solvent, reactant concentrations, etc) were optimized to yield a panel of carbohydrate derivatives (some examples of the structures obtained are given above). These differ by the nature of the alkyl chain (in length and in degree of saturation), the type of chemical bond (amide, ester, thioester, acetal), and the position of substitution. The impact of these differences on the techno-functional properties of these modified sugars will be evaluated. [less ▲]

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See detailRouting Based on Delivery Distributions in Predictable Disruption Tolerant Networks
François, Jean-Marc; Leduc, Guy ULg

in Ad hoc Networks (2009), 7(1), 219-229

This article studies disruption tolerant networks (DTNs) where each node knows the probabilistic distribution of contacts with other nodes. It proposes a framework that allows one to formalize the ... [more ▼]

This article studies disruption tolerant networks (DTNs) where each node knows the probabilistic distribution of contacts with other nodes. It proposes a framework that allows one to formalize the behaviour of such a network. It generalizes extreme cases that have been studied before where (a) either nodes only know their contact frequency with each other or (b) they have a perfect knowledge of who meets who and when. This paper then gives an example of how this framework can be used; it shows how one can find a packet forwarding algorithm optimized to meet the ‘delay/bandwidth consumption’ tradeoff: packets are duplicated so as to (statistically) guarantee a given delay or delivery probability, but not too much so as to reduce the bandwidth, energy, and memory consumption. [less ▲]

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See detailPhytoplankton ecology of Lake Kivu (eastern Africa): biomass, production and elemental ratios
Sarmento, Hugo; Isumbisho, Mwapu; Stenuite, Stephan et al

in Verhandlungen der Internationalen Vereinigung für Theoretische und Angewandte Limnologie = Proceedings of the International Association of Theoretical and Applied Limnology (2009, January), 30(5), 709-713

Detailed reference viewed: 15 (0 ULg)