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See detailA physically motivated pixel-based model for background subtraction in 3D images
Braham, Marc ULg; Lejeune, Antoine ULg; Van Droogenbroeck, Marc ULg

in International Conference on 3D Imaging (IC3D) (2014, December)

This paper proposes a new pixel-based background subtraction technique, applicable to range images, to detect motion. Our method exploits the physical meaning of depth information, which leads to an ... [more ▼]

This paper proposes a new pixel-based background subtraction technique, applicable to range images, to detect motion. Our method exploits the physical meaning of depth information, which leads to an improved background/foreground segmentation and the instantaneous suppression of ghosts that would appear on color images. In particular, our technique considers certain characteristics of depth measurements, such as failures for certain pixels or the non-uniformity of the spatial distribution of noise in range images, to build an improved pixel-based background model. Experiments show that incorporating specificities related to depth measurements allows us to propose a method whose performance is increased with respect to other state-of-the-art methods. [less ▲]

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See detailManifesto de Curitiba: pela Prevenção Quaternária e por uma Medicina sem conflitos de interesse
Silva, André Luiz da; Mangin, Derelie; Pizzanelli, Miguel et al

in Revista Brasileira de Medicina de Família e Comunidade (2014), 9(33), 371-374

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See detailThe European Certificate of Succession
Wautelet, Patrick ULg

Scientific conference (2014, December)

Cette présentation offre un aperçu des principes généraux qui gouvernent l'octroi et l'utilisation du certificat successoral européen tel que mis en place par le Règlement 650/2012 relatif aux successions.

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See detailLes Phénomènes
Dewalque, Arnaud ULg; Seron, Denis ULg

in Philosophie (2014), 124

Le présent numéro thématique explore quelques aspects de la question de la phénoménalité. Les trois premiers textes portent sur les phénomènes sensibles: sur le nombre des sens (Brentano), le traitement ... [more ▼]

Le présent numéro thématique explore quelques aspects de la question de la phénoménalité. Les trois premiers textes portent sur les phénomènes sensibles: sur le nombre des sens (Brentano), le traitement des phénomènes sensibles dans la phénoménologie de Husserl (Stumpf) et l'héritage du phénoménisme de Mach dans le néokantisme de Natorp (Palette). Les contributions suivantes s’inscrivent dans le cadre du débat contemporain sur la conscience phénoménale. Elles discutent la pertinence et les difficultés d’une approche phénoménologique du monde (Uriah Kriegel), de l’intentionnalité (Dan Zahavi) et du mental (Dewalque & Seron). [less ▲]

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See detailA New Shift-Share Method
Artige, Lionel ULg; Van Neuss, Leif ULg

in Growth and Change (2014), 45(4), 667-683

Shift-share analysis is a decomposition technique widely used in regional studies to quantify an industry-mix effect and a competitive effect on the growth of regional employment (or any other relevant ... [more ▼]

Shift-share analysis is a decomposition technique widely used in regional studies to quantify an industry-mix effect and a competitive effect on the growth of regional employment (or any other relevant variable) relative to the national average. This technique has always been subject to criticism for its lack of theoretical basis. This paper presents a critical assessment of the methods suggested by Dunn (1960) and by Esteban-Marquillas (1972) and proposes a new shift-share method, which separates out the two effects unambiguously. By way of illustration, we provide an application to manufacturing employment in the Belgian provinces between 1995 and 2007. [less ▲]

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See detailAboveground biomass mapping of African forest mosaics using canopy texture analysis: toward a regional approach.
Bastin, Jean-François ULg; Barbier, Nicolas; Couteron, Pierre et al

in Ecological Applications (2014), 24(8), 1984-2001

In the context of the reduction of greenhouse gas emissions caused by deforestation and forest degradation (the REDD+ program), optical very high resolution (VHR) satellite images provide an opportunity ... [more ▼]

In the context of the reduction of greenhouse gas emissions caused by deforestation and forest degradation (the REDD+ program), optical very high resolution (VHR) satellite images provide an opportunity to characterize forest canopy structure and to quantify aboveground biomass (AGB) at less expense than methods based on airborne remote sensing data. Among the methods for processing these VHR images, Fourier textural ordination (FOTO) presents a good potential to detect forest canopy structural heterogeneity and therefore to predict AGB variations. Notably, the method does not saturate at intermediate AGB values as do pixelwise processing of available space borne optical and radar signals. However, a regional scale application requires to overcome two difficulties: (i) instrumental effects due to variations in sun-scene-sensor geometry or sensor-specific responses that preclude the use of wide arrays of images acquired under heterogeneous conditions and (ii) forest structural diversity including monodominant or open canopy forests, which are of particular importance in Central Africa. In this study, we demonstrate the feasibility of a rigorous regional study of canopy texture by harmonizing FOTO indices of images acquired from two different sensors (Geoeye-1 and QuickBird-2) and different sun-scene-sensor geometries and by calibrating a piecewise biomass inversion model using 26 inventory plots (1 ha) sampled across very heterogeneous forest types. A good agreement was found between observed and predicted AGB (RSE=15%; R²=0.85; p-value<0.001) across a wide range of AGB levels from 26 Mg/ha to 460 Mg/ha, and was confirmed by cross validation. A high-resolution biomass map (100 m pixels) was produced for a 400 km² area, and predictions obtained from both imagery sources were consistent with each other (r=0.86; slope=1.03; intercept=12.01 Mg/ha). These results highlight the horizontal structure of forest canopy as a powerful descriptor of the entire forest stand structure and heterogeneity. In particular, we show that quantitative metrics resulting from such textural analysis offer new opportunities to characterize the spatial and temporal variation of the structure of dense forests and may complement the toolbox used by tropical forest ecologists, managers or REDD+ national monitoring, reporting and verification bodies. [less ▲]

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See detailEmpirical modelling of the bifurcation behaviour of a bridge deck undergoing across-wind galloping
Andrianne, Thomas ULg; Dimitriadis, Grigorios ULg

in Journal of Wind Engineering & Industrial Aerodynamics (2014), 135

This work presents an empirical model capable to describe the galloping bifurcation behaviour of a bridge deck. It is based on a general polynomial form proposed by Novak, which we limit to the 5th order ... [more ▼]

This work presents an empirical model capable to describe the galloping bifurcation behaviour of a bridge deck. It is based on a general polynomial form proposed by Novak, which we limit to the 5th order. The advantage of choosing this function for modelling the vertical force coefficient is that asymmetry of the even terms is enforced in order to reproduce the sub-critical aeroelastic behaviour of the bridge deck. The coefficients of the polynomial are identified from several pairs of displacement amplitudes and the corresponding airspeeds, measured in a wind tunnel during dynamic tests on the sectional bridge model. The identification is carried out using a first order harmonic balance technique. A stability analysis is presented in order to highlight the need of such a model to catch the complete bifurcation behaviour of the system. The resulting force coefficient of this full order model is compared to the well known models of Parkinson and Novak. Finally, the concept universal curve is used in order to discuss the galloping responses of square and rectangular cylinders, in comparison with the one of the bridge deck. [less ▲]

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See detailEcological diversity of damselfishes (Pomacentridae) from Moorea
Gajdzik, Laura ULg; Parmentier, Eric ULg; Lepoint, Gilles ULg et al

Poster (2014, December)

The Pomacentridae (damselfishes) represents the 3rd most species-rich coral reef fish family, including 394 species spread worldwide. Recent studies suggested that damselfishes iteratively evolve along ... [more ▼]

The Pomacentridae (damselfishes) represents the 3rd most species-rich coral reef fish family, including 394 species spread worldwide. Recent studies suggested that damselfishes iteratively evolve along three main trophic guilds: “the pelagic feeders” feeding mainly on zooplankton, “the benthic feeders” grazing filamentous algae or biting coral polyps, and an “intermediate” group with species feeding on zooplankton, small benthic invertebrates and algae in variable proportions. Comparing the ecological diversity of damselfish communities among various geographical regions could assess such an iterative radiation. Within this context, the present study is a first attempt exploring the trophic diversity of damselfish community at Moorea Island (French Polynesia). The relationship between the trophic guilds, their habitat diversity and their behavior is evaluated. Habitat and behaviour of 16 damselfish species were described during transects along which different kinds of data were collected. For examples, the location within the reef (e.g. fringing or barrier reef), the depth, the substrate over which fishes are living or the solitary/gregarious habits were recorded. Diet of individuals was investigated by means of stomach content and stable isotopes analyses. Correlations between the dietary preferences and ecological data (habitat and behaviour) are given and the ecological diversity among trophic groups is compared. [less ▲]

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See detailThe influence of bioavailable copper and zinc concentrations on metallothionein levels, DNA damage and gene expression in the polychaete Nereis (Alitta) virens (M. Sars, 1835)
Pini, Jennifer; Richir, Jonathan ULg; Watson, Gordon

Poster (2014, December)

Nereis (Alitta) virens is an ecologically and commercially important polychaete of intertidal soft sediment and an ideal species to investigate long term effects of metals. Using a spike approach, worms ... [more ▼]

Nereis (Alitta) virens is an ecologically and commercially important polychaete of intertidal soft sediment and an ideal species to investigate long term effects of metals. Using a spike approach, worms (1-3 g) were incubated for nine months in sediments spiked at environmentally relevant concentrations of copper, zinc and copper & zinc together: low (copper: 70 mg kg-1, zinc: 200 mg kg-1), medium (copper 120 mg kg-1, zinc: 270 mg kg-1) and high (copper 575 mg kg-1, zinc: 1160 mg kg-1) concentrations. These concentrations were based on an extensive sampling regime of sediment, pore water and worms from seven sites with different levels of contamination across the UK. Worms were fed and maintained under ambient conditions in a flow-through seawater system and sampled at 3, 6 and 9 months. Using BCR sequential extraction, bioavailable metal concentrations in the sediment were assessed in addition to pore water and tissues metal concentrations. The induction of metallothionein (MT) activity, especially at month 6, revealed the detoxification potential of N. virens under metal stress conditions. Significant correlations were obtained between copper bioavailable concentrations in the sediment and MT levels at month 3 and between zinc bioavailable concentrations in the sediment and MT levels at month 6. The highest DNA damage was recorded at month 3 for high copper & zinc combined treatment with 36.44%. Significant correlations were obtained between sediment bioavailable metal concentrations and DNA damage. In addition, the study of metal induced gene expression will reveal for the first time metal regulation process in the polychaete N. virens. This study showed that (1) not only high copper was toxic to N. virens but high copper & zinc combined treatment was the most toxic to the worms and (2) MT and DNA damage were sensitive and reliable endpoints used to evaluate copper and zinc toxicity. [less ▲]

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See detailEcology of 20 trace elements in Mytilus galloprovincialis
Richir, Jonathan ULg; Lepoint, Gilles ULg; Lejeune, Pierre et al

Conference (2014, December)

Trace elements (TEs) are considered as non-degradable pollutants. This persistent character can alter their natural biogeochemical balance in contaminated environments. TEs are further toxic for aquatic ... [more ▼]

Trace elements (TEs) are considered as non-degradable pollutants. This persistent character can alter their natural biogeochemical balance in contaminated environments. TEs are further toxic for aquatic organisms from threshold levels and are thus likely to cause multiple damages to the population, the community and the ecosystem levels. For these reasons, their environmental occurrence has to be accurately monitored. The main interest of the use of quantitative sentinel organisms to this end, or bioindicator species, is their capacity to give information on the bioavailability of environmental contaminants. Mussels from the genus Mytilus are particularly well suited organisms for the monitoring of the coastal contamination. Native wild and cultured Mytilus galloprovincialis Lamarck, 1819 have been widely used since around 40 years to this purpose along coasts of the eastern Atlantic and the Mediterranean. But the accurate use of a bioindicator relies on the detailed knowledge of its ecophysiology and the influence of environmental variables on the bioaccumulation processes. In the framework of the STARECAPMED project, the ecology of 20 TEs in M. galloprovincialis is therefore investigated. The mussel morphometry and biology firstly define the TE accumulation processes. Accumulated TE are internally regulated and redistributed between body compartments; these internal processes notably depend on the essential or non-essential character of TEs. As filter feeder, mussels accumulate soluble and suspended TEs whose environmental levels are determined by the geomorphology, the physico-chemistry and the hydrology of monitored coastal meadows. All these factors are acting together to modulate the TE accumulation processes in mussels. TE bioaccumulated levels further balance quickly when any physiological or environmental changes occur in order to reach a new steady-state with environmental TE loads. The ecology of TEs in M. galloprovincialis is thus complex and very dynamic; these considerations must be taken into account when monitoring the chemical contamination of coastal meadows. [less ▲]

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See detailLe relief de Neumagen et les bibliothèques antiques
Marganne, Marie-Hélène ULg

in Capasso, Mario; De Nonno, Mario (Eds.) Scritti in memoria di Paolo Radiciotti (2014)

Mise en contexte du relief de Neumagen aujourd'hui disparu représentant une bibliothèque avec des rouleaux de papyrus et recherches sur les circonstances de la publication, à Liège, en 1670, par l ... [more ▼]

Mise en contexte du relief de Neumagen aujourd'hui disparu représentant une bibliothèque avec des rouleaux de papyrus et recherches sur les circonstances de la publication, à Liège, en 1670, par l'imprimeur Jean Matthias Hovius, des Antiquitatum et Annalium Trevirensium libri XXV de Ch. Brouwer et J. Masen contenant la gravure de ce relief. [less ▲]

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See detailLes fondamentaux de la valeur des entreprises en Europe
Lambert, Marie ULg; Lenglois, Julien; Streel, Alexandre ULg et al

in Comptabilité et Fiscalité Pratiques (2014)

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See detailEnfants en situation de vulnérabilité médico-psycho-sociale repérés par la médecine scolaire : les oubliés du réseau de soins ?
Noirhomme-Renard, Florence ULg; Bullens, Quentin ULg; Malchair, Alain ULg et al

in Revue Médicale de Liège (2014), 69(12),

Les besoins actuels de santé des enfants sortent largement du cadre biomédical. La prise en compte des déterminants sociaux de la santé dans la surveillance des enfants offre au médecin scolaire un poste ... [more ▼]

Les besoins actuels de santé des enfants sortent largement du cadre biomédical. La prise en compte des déterminants sociaux de la santé dans la surveillance des enfants offre au médecin scolaire un poste « vigie » pour le repérage d’enfants en situation de vulnérabilité, qui le conduit à la nécessité d’un réel « travail en réseau » pour concourir au développement harmonieux de l’enfant. [less ▲]

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See detailImpact of shading on meiofauna in a Posidonia oceanica meadow
Pete, Dorothée ULg; Gobert, Sylvie ULg

Poster (2014, December)

Posidonia oceanica meadow is an endemic ecosystem of the Mediterranean coasts. A known threat to this ecosystem is aquaculture. In zones of intensive fish production, P. oceanica meadow tends to be less ... [more ▼]

Posidonia oceanica meadow is an endemic ecosystem of the Mediterranean coasts. A known threat to this ecosystem is aquaculture. In zones of intensive fish production, P. oceanica meadow tends to be less healthy or to disappear .One of the reasons for this is a decrease in the light that reaches the leaves (direct shading, increase of water turbidity or of epiphytic algae density). Unfortunately, when the meadow begins to die, it is often too late to act. So, people are trying to find indicators that react early to this kind of perturbations. In this framework, this study focuses on the impact of shading (without nutrient enrichment) on the meiofauna living in the surface sediment of a P. oceanica meadow. An in situ shading experiment was led from the end of May to the end of August 2009, at a depth of 10 m, in a reference P. oceanica meadow. Three shading nets were put in the meadow to reach a light extinction of 50%. A control site was also defined. The first two centimetres of sampled sediment cores were studied. After three months of shading, the total abundance of meiofauna at the shading site was lower than at the beginning of the experiment, while it stayed around the same level at the control site. This difference is mainly due to a decrease in the total number of foraminiferans, nematods, gnathostomulids, copepods and bivalves. However, no significant difference in diversity was observed. At the end of this experiment, it appeared that, contrarily to what is mostly said in the literature, the direct organic enrichment that occurs at fish farms is not the only reason to the modification of the meiofauna communities of the ecosystem. The shading by itself has also an effect. [less ▲]

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See detailCan EU Consumer Law Benefit from Behavioural Insights? An Analysis of the Unfair Practices Directive
Sibony, Anne-Lise ULg

in Mathis, Klaus (Ed.) European Perspectives on Behavioural Law and Economics (2014)

This paper explores in what ways insights from social psychology could be used to shape the interpretation of European law on unfair practices. It is argued that insights from social psychology on ... [more ▼]

This paper explores in what ways insights from social psychology could be used to shape the interpretation of European law on unfair practices. It is argued that insights from social psychology on influencing techniques are relevant to the interpretation of the directive on unfair practices. Both conceptual and empirical insights from psychology are valuable from a legal point of view. They could respectively translate as new elements of legal tests or as presumptions. [less ▲]

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