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See detailReconstruction of Missing Satellite Total Suspended Matter Data over the Southern North Sea and English Channel using Empirical Orthogonal Function Decomposition of Satellite Imagery and Hydrodynamical Modelling
Sirjacobs, Damien ULg; Alvera Azcarate, Aïda ULg; Barth, Alexander ULg et al

Poster (2008, October)

Optical remote sensing data archives generally have many gaps caused by clouds or other retrieval problems. However, for the light forcing of ecosystem models continuous fields are required. For ... [more ▼]

Optical remote sensing data archives generally have many gaps caused by clouds or other retrieval problems. However, for the light forcing of ecosystem models continuous fields are required. For parameters exhibiting strong spatial and temporal correlations for regions of similar dynamics or from day to day, the missing data can be estimated by use of statistical techniques. In this context, the Data Interpolation with Empirical Orthogonal Functions (DINEOF) method is used for reconstruction of complete space-time information for surface total suspended matter (TSM) and chlorophyll a from a 5-year archive of MODIS and MERIS products over the Southern North Sea and English Channel. The DINEOF univariate methodology has been previously demonstrated for Mediterranean sea surface temperature data (Alvera-Azcarate et al., 2005, Beckers et al., 2006). Alvera-Azcarate et al (2007) showed that SST reconstructions could be improved by using a multivariate approach in which SST, chlorophyll and wind fields were taken into account together for the analyses. Here, TSM images will be used in combination with information from the COHERENS hydrodynamical model to provide a complete and continuous estimate of surface TSM for the Southern North Sea throughout the period 2003-2005. In addition to the remotely sensed TSM, the DINEOF multivariate analysis will consider wind fields, depth integrated currents, surface elevations and bottom stresses. Reconstucted images are compared with the original incomplete images. Validation of the method is achieved by estimation of information removed from the training data by exclusion of entire images and by addition of artificial clouds. The data reconstruction technique has further applications in the processing and quality control of optical remote sensing data. Perspectives will be outlined for improving the quality control of retrieved parameters and for the improvement of retrievals by adding statistical information to the conventional spectral processing. References: Alvera-Azcarate, A., Barth, A., Rixen, M., and Beckers, J.-M.: Reconstruction of incomplete oceanographic data sets using Empirical Orthogonal Functions. Application to the Adriatic Sea, Ocean Modelling, 9, 325–346, 2005. Alvera-Azcarate, A., Barth, A., Beckers, J. M., and Weisberg, R. H.: Multivariate Reconstruction of Missing Data in Sea Surface Temperature, Chlorophyll and Wind Satellite Fields, Journal of Geophysical Research, 112, C03008, doi:10.1029/2006JC003660, 2007. Beckers J.-M., A. Barth & A. Alvera-Azcarate, DINEOF reconstruction of clouded images including error maps. Application to the Sea-Surface Temperature around Corsican Island, Ocean Sciences, 2: 183–199, 2006. [less ▲]

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See detailTesting methods applicable to refrigeration components and systems
Quoilin, Sylvain ULg

Poster (2008, October)

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See detailModeling and experimental investigation of an Organic Rankine Cycle using scroll expander for small scale solar applications
Quoilin, Sylvain ULg; Orosz, Matthew; Lemort, Vincent ULg

(2008, October)

This study aims at developing and optimizing an Organic Rankine Cycle (ORC) for a small scale, decentralized parabolic trough system. A numerical model the Organic Rankine Cycle is developed and an ... [more ▼]

This study aims at developing and optimizing an Organic Rankine Cycle (ORC) for a small scale, decentralized parabolic trough system. A numerical model the Organic Rankine Cycle is developed and an experimental study is carried out on an ORC prototype working with refrigerant HCFC-123, and whose heat sources consist in two hot air flows. The ORC model is built by connecting different sub-models: the heat exchanger models, a volumetric pump model and a scroll expander model. Measured performances of the ORC prototype are presented and allow the validation of the ORC model. [less ▲]

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See detailPEO coated magnetic nanoparticles for biomedical application
Aqil, Abdelhafid ULg; Vasseur, S.; Duguet, E. et al

in European Polymer Journal (2008), 44(10), 3191-3199

This paper reports on the preparation, characterization and stealthiness of superparamagnetic nanoparticles (magnetite Fe3O4) with a 5 nm diameter and stabilized in water (pH 6.5) by a shell of water ... [more ▼]

This paper reports on the preparation, characterization and stealthiness of superparamagnetic nanoparticles (magnetite Fe3O4) with a 5 nm diameter and stabilized in water (pH 6.5) by a shell of water-soluble poly(ethylene oxide) (PEO) chains. Two types of diblock copolymers, i.e., poly(acrylic acid)-b-poly(ethylene oxide), PAA–PEO, and poly(acrylic acid)-b-poly(acrylate methoxy poly(ethyleneoxide)), PAA–PAMPEO, were prepared as stabilizers with different compositions and molecular weights. At pH 6.5, the negatively ionized PAA block interacts strongly with the positively-charged nanoparticles, thus playing the role of an anchoring block. Aggregates of coated nanoparticles were actually observed by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The hydrodynamic diameter was in the 50–100 nm range and the aggregation number (number of nanoparticles per aggregate) was lying between several tens and hundred. Moreover, the stealthiness of these aggregates was assessed “in vitro” by the hemolytic CH50 test. No response of the complement system was observed, such that biomedical applications can be envisioned for these magnetic nanoparticles. Preliminary experiments of magnetic heating (10 kA/m; 108 kHz) were performed and specific absorption rate varied from 2 to 13 W/g(Fe). [less ▲]

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See detailUne lecture scientométrique de la littérature sur les réseaux sociaux en sciences de gestion et en entrepreneuriat
Froehlicher, Thomas ULg; Bares, Franck; Bourgne, Patrick

Conference (2008, October)

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See detailLa répression de la négation du génocide arménien en Belgique : enjeux pluriels pour une absence de décision
Grandjean, Geoffrey ULg

Article for general public (2008)

This article tries to explain the discussions which occured in Belgium in 2006 and 2007 concerning the punishment of armenian genocide-denial.

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See detailLa mort en partage. A propos du Tombeau de Théophile Gautier
Durand, Pascal ULg

in Histoires littéraires (2008), 36

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See detailDéfauts d'orientation et de battement
Debongnie, Jean-François ULg

Report (2008)

The problem of orientation or runout errors being formulated, it is firt noted that these errors necessarily include the form errors of the measured part. The second problem is the correct asseement of a ... [more ▼]

The problem of orientation or runout errors being formulated, it is firt noted that these errors necessarily include the form errors of the measured part. The second problem is the correct asseement of a simulated reference when the reference surface is of imperfect form. The logical choice would be perfect form having the least maximal distance to the physical one. But this choice being a difficult one, the best approximation in the least square sense if often chosed. The effect of this reference perturbation is studied. [less ▲]

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See detailNew simulation tools usable in the energy audit of HVAC systems
Lebrun, Jean ULg; Bertagnolio, Stéphane ULg

Scientific conference (2008, October)

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See detailIntrasaccular injection of aminoglycosides: a novel method for temporary damaging fish inner ear hair cells
Faucher, Karine ULg; Aas-Hansen, Øyvind; Damsgard, Borge et al

Poster (2008, October)

Fish models are increasingly being used for hearing research investigations. Aminoglycoside antibiotics that are used for damaging the inner ear hair cells can have systemic side effects leading to death ... [more ▼]

Fish models are increasingly being used for hearing research investigations. Aminoglycoside antibiotics that are used for damaging the inner ear hair cells can have systemic side effects leading to death of study animals. This study aimed to compare two methods: i) systemic (intravenous) and ii) local (intrasaccular) gentamicin administration for induction of inner ear hair cell damage in the Atlantic cod, Gadus morhua (L.). Hair cell damage was assessed using scanning electron microscopy; hair cell density, prevalence of immature hair cells and kinocilia length were measured. Gentamicin-treated fish were compared with control and sham fish. Intravenous gentamicin led to dose-dependent mortality caused by nephrotoxicity. The only visible effect after treatment was more immature hair cells and shorter kinocilia, the effect on hair cell density was equivocal. Following intrasaccular gentamicin treatment, fish mortality was negligible, and hair cells were damaged regardless of dose. Here, we observed decreased hair cell density, high prevalence of immature hair cells, and significantly shortened kinocilia. Conclusion: intrasaccular injection is preferable to intravenous injection of gentamicin for the study of ototoxicity in the Atlantic cod. [less ▲]

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See detailModélisation hydrodynamique 2D et SIG à haute résolution pour l’évaluation de mesures de protection contre les inondations en milieu urbain
Ernst, Julien ULg; Dewals, Benjamin ULg; Archambeau, Pierre ULg et al

in 3e journées doctorales en hydrologie urbaine (2008, October)

Within the global framework of climate change, the majority of the regional climatic models (RCM - Regional Climatic Model) predict an increase in the frequency and importance of the rainy events ... [more ▼]

Within the global framework of climate change, the majority of the regional climatic models (RCM - Regional Climatic Model) predict an increase in the frequency and importance of the rainy events. Therefore, the populations will have to face an increased risk of flooding. In order to draw up suitable protection strategy in this context, decision-making tool must be developed to select the adequate mitigation measure among the whole of the possible protection measures. This system has to take into account parameters such as hydraulic economic, social or environmental. This paper focuses on the integration between the economic evaluation of the undergone damage and the two-dimensional hydrodynamic modelling implemented using the model WOLF 2D. The integration is ensured by the use of pointed geographical information systems and an automated procedure, based on the methods of geomatic, guaranteeing a perfect applicability of methodology for the analysis of urban areas. The whole of methodology is then applied to the evaluation of a measurement of adaptation to Ourthe (basin of the Meuse), namely the rehabilitation of an old channel formerly used to allow the river transport to the river. [less ▲]

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See detailMulti-scale spatial variability of amphipod assemblages from the foliar stratum of the Posidonia oceanica (L.) Delile meadow
Sturaro, Nicolas ULg; Lepoint, Gilles ULg; Michel, Loïc ULg et al

Conference (2008, October)

Studying spatial patterns is of ecological importance in order to understand the causes of the distribution and abundance of organisms, and it also provides valuable basis for management and conservation ... [more ▼]

Studying spatial patterns is of ecological importance in order to understand the causes of the distribution and abundance of organisms, and it also provides valuable basis for management and conservation. In the Mediterranean coastal zone, the Posidonia oceanica seagrass meadows constitute one of the dominant ecosystems and are an important habitat for vagile invertebrates. Among these, amphipods comprise a large number of species, with considerable abundance and biomass, as well as being an important trophic resource for fish populations. Until now, little attention has been given to the horizontal variability at different spatial scales of amphipod assemblages associated with P. oceanica meadows. A hierarchical sampling design, spanning three orders of magnitude (from 1 to 100s of metres) was elaborated. Sampling was undertaken in March 2007 in the meadows of Calvi Bay (NW Corsica), at depths ranging from 10 to 13 m, using a suction sampler. Our results indicated an important horizontal variability of the studied assemblage, and this at different spatial scales. In addition, these results tend to show that the small scale (~ 1 m and ~ 10 m) influenced abundance, while the medium-scale (~ 100 m) influenced diversity. Some potential causes of the observed patterns are discussed. These results emphasize the importance of considering different spatial scales in the study of the vagile invertebrates associated with P. oceanica meadows. [less ▲]

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See detailBases biologiques et éco-hydrauliques pour la restauration de la continuité piscicole en rivière : premier bilan et perspectives en Région Wallonne (Belgique).
Ovidio, Michaël ULg; Philippart, Jean-Claude ULg; Denoel, Philippe et al

Conference (2008, October)

Dans le prolongement de la Directive Benelux d’avril 1996 (libre circulation des poissons migrateurs) et de la Directive Cadre sur l’Eau de l’Union Européenne (2000/60/CE), le rétablissement de la ... [more ▼]

Dans le prolongement de la Directive Benelux d’avril 1996 (libre circulation des poissons migrateurs) et de la Directive Cadre sur l’Eau de l’Union Européenne (2000/60/CE), le rétablissement de la continuité piscicole dans nos cours d’eau fait partie des objectifs prioritaires de la Direction des Cours d’eau Non Navigables du Ministère de la Région Wallonne. Depuis 1997, différents acteurs, gestionnaires, sociétés de pêches et scientifiques abordent en profondeur cette problématique par l’exécution de différentes actions intégrées. Depuis environ 10 ans, un travail de terrain considérable est accompli pour le compte de la Région wallonne par la Fédération de Pêche Vesdre-Amblève (asbl) qui répertorie et géoréférence la totalité des obstacles physiques susceptibles de perturber la continuité piscicole dans les cours d’eau de Wallonie. En parallèle, le Laboratoire de Démographie des Poissons et d’Hydroécologie (LDPH) de l’Université de Liège étudie l’impact biologique de certains de ces obstacles sur les populations de poissons, principalement en utilisant la technique du radio-pistage. Ces recherches permettent de mieux connaître les phénomènes de mobilité et de migrations des poissons de nos cours d’eau ainsi que leurs capacités à franchir en remontée des obstacles typologiquement très différents. Ces travaux permettent d’identifier les sites critiques qui doivent prioritairement êtres équipés de dispositifs de franchissement efficaces. Le contrôle scientifique du fonctionnement des passes migratoires nouvellement construites démontre clairement leurs effets positifs sur la qualité écologique et piscicole de la rivière. De tels résultats justifient fortement de multiplier ce type d’action de restauration écologique (hydromorphologique) dans d’autres cours d’eau. Au cours de notre exposé, nous présenterons, avec des résultats concrets, un premier bilan des travaux déjà effectués et nous dégagerons les perspectives à moyen et long terme en matière de libre circulation des poissons dans les cours d’eau wallons, non seulement en remontée mais aussi en descente (ou dévalaison). [less ▲]

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See detailSimulation-assisted audit of an air conditioned building
Bertagnolio, Stéphane ULg; Lebrun, Jean ULg; Hannay, Cleide ULg et al

in Proceedings of the 8th International Conference for Enhanced Building Operation, Berlin, Germany (2008, October)

The example presented here concerns the audit of a typical, medium-size, office building erected in Brussels at the end of the sixties. This building is equipped with a classical old fashioned air ... [more ▼]

The example presented here concerns the audit of a typical, medium-size, office building erected in Brussels at the end of the sixties. This building is equipped with a classical old fashioned air conditioning system with air handling units and four-pipes induction units. In the first part of the paper, a classical audit procedure is applied. It consists in a systematic analysis of all information available, with help of very simple calculation. In the second part of the paper, an equation-based building-HVAC simulation tool is used to assist the audit. Fuel and electricity consumption are then interpreted and significant energy saving opportunities are identified. [less ▲]

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See detailEcology and silviculture of black alder (Alnus glutinosa (L.) Gaertn.)
Claessens, Hugues ULg; Oosterbaan, Anne; Savill, Peter

Poster (2008, October)

Black alder (Alnus glutinosa (L.) Gaertn.) is widespread across Europe, both in forest and on open land along the watercourses. It plays a major role in nature conservation, thanks to its relation with ... [more ▼]

Black alder (Alnus glutinosa (L.) Gaertn.) is widespread across Europe, both in forest and on open land along the watercourses. It plays a major role in nature conservation, thanks to its relation with the river ecosystems and its network distribution on open land. [less ▲]

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See detailChirurgie pédiatrique en exemples
Battisti, Oreste ULg

Learning material (2008)

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