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See detailI know what you did last summer - High resolution mapping of wild boar damages with drones
Michez, Adrien ULg; Morelle, Kevin ULg; Lehaire, François ULg et al

Poster (2014, September 01)

Wild boar ability to cause important damages to agricultural lands is not anymore to be demonstrated. These damages often raise conflicts between farmers and hunters due to the associated economic losses ... [more ▼]

Wild boar ability to cause important damages to agricultural lands is not anymore to be demonstrated. These damages often raise conflicts between farmers and hunters due to the associated economic losses. Objective and accurate method for real impact assessment of losses suffered by farmers is thus needed. Currently,in Wallonia damage assessment is performed from the ground by experts, asked to evaluate precisely the area impacted. This task is time and man power consuming. Moreover, damaged areas are often large and consequently, sampling is mandatory and can induce accuracy issues. Recent development of unmanned aerial vehicle (UAV / drone) toghether with lower cost and better accessibility for civil society and scientific community, makes now possible the use of this technology for wildlife researches. Through photogrammetric 3D reconstruction of the field crop, UAV can allow to objectively and precisely measure the area impacted by wild boar damages. In a context of increasing issues caused by wild boar to agriculture, and the need for stakeholders for accurate impact assessment, we tested an innovative approach to estimate more effectively the area impacted by wild boar. [less ▲]

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See detailElastic damage to crack transition in a coupled non-local implicit discontinuous Galerkin/extrinsic cohesive law framework
Wu, Ling ULg; Becker, Gauthier ULg; Noels, Ludovic ULg

in Computer Methods in Applied Mechanics & Engineering (2014), 279

One current challenge related to computational fracture mechanics is the modeling of ductile fracture and in particular the damage to crack transition. On the one hand, continuum damage models, especially ... [more ▼]

One current challenge related to computational fracture mechanics is the modeling of ductile fracture and in particular the damage to crack transition. On the one hand, continuum damage models, especially in their non-local formulation which avoids the loss of solution uniqueness, can capture the material degradation process up to the localization of the damage, but are unable to represent a discontinuity in the structure. On the other hand cohesive zone methods can represent the process zone at the crack tip governing the crack propagation, but cannot account for the diffuse material damaging process. In this paper we propose to combine, in a small deformations setting, a non-local elastic damage model with a cohesive zone model. This combination is formulated within a discontinuous Galerkin nite element discretization. Indeed this DG weak formulation can easily be developed in a non-local implicit form and naturally embeds interface elements that can be used to integrate the traction separation law of the cohesive zone model. The method remains thus consistent and computationally e cient as compared to other cohesive element approaches. The effects of the damage to crack transition and of the mesh discretization are respectively studied on the compact tension specimen and on the double-notched specimen, demonstrating the efficiency and accuracy of the method. [less ▲]

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See detailTechnical variability in the Gravettian with tanged tools: new results from Belgium
Touzé, Olivier; Flas, Damien ULg; Pesesse, Damien

Conference (2014, September 01)

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See detailPhase resolved X-ray spectroscopy of HDE 228766: Probing the wind of an extreme Of+/WNLha star (Corrigendum)
Rauw, Grégor ULg; Mahy, Laurent; Nazé, Yaël ULg et al

in Astronomy and Astrophysics (2014), 569

Based on observations collected with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA member states and the USA (NASA), and on data collected at the San Pedro ... [more ▼]

Based on observations collected with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA member states and the USA (NASA), and on data collected at the San Pedro Mártir observatory (Mexico). Corrigendum [less ▲]

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See detailThe B Fields in OB Stars (BOB) Survey
Morel, Thierry ULg; Castro, N.; Fossati, L. et al

in The Messenger (2014), 157

The B fields in OB stars (BOB) survey is an ESO Large Programme collecting spectropolarimetric observations for a large number of early-type stars in order to study the occurrence rate, properties, and ... [more ▼]

The B fields in OB stars (BOB) survey is an ESO Large Programme collecting spectropolarimetric observations for a large number of early-type stars in order to study the occurrence rate, properties, and ultimately the origin of magnetic fields in massive stars. A total of 98 objects was observed over 20 nights with FORS2 and HARPSpol to July 2014. Preliminary results indicate that the fraction of magnetic OB stars with an organised, detectable field is low. This conclusion, now independently reached by two different surveys, has profound implications for any theoretical model attempting to explain the field formation in these stars. We also discuss some important issues addressed by our observations (e.g., the lower bound of the field strength) and the discovery of some remarkable objects. [less ▲]

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See detailTechnical variability into the Gravettian with tanged tools: new results from Belgium
Touzé, Olivier ULg; Flas, Damien ULg; Pesesse, Damien

Conference (2014, September 01)

Located at the interface between the Paris and the Rhine basins and the more northern territories of Europe, Belgium yield several gravettian occupations, all of which are located in the southern half of ... [more ▼]

Located at the interface between the Paris and the Rhine basins and the more northern territories of Europe, Belgium yield several gravettian occupations, all of which are located in the southern half of the country. The work of M. Otte in the second part of the seventies permitted to inventory eight deposits attributable to the Gravettian, and more than twice sites delivering clues that also evoke this period (Otte, 1979). But the quality of the documentation doesn't always respond to its quantity. Indeed, the analysis of the data is frequently complicated by the antiquity of the excavations conducted in most gravettian sites. The stratified records in karst context are particularly affected by this situation, thus restraining studies on the gravettian chronology in Belgium. This overview is however partly counterbalanced by two open air deposits excavated during the second half of the XXth century, and which benefited of good condition of preservation as well as more modern excavation methods: Maisieres-Canal (de Heinzelin, 1973; Haesaerts & de Heinzelin, 1979) and Station de l'Hermitage (Straus et al., 2000). These two deposits have often been the object of comparisons highlighting their similarities, both in term of spatial establishment and in term of lithic industry. In fact, their lithic industries stand out by the presence of tanged tools, a typological marker usually associated with the early Gravettian of Western Europe, and also encountered in other Belgian sites, particularly in the Betche-aux-Roches cave in Spy recently studied by two of us (Pesesse & Flas, 2014). If Maisieres-Canal and Station de l'Hermitage might have been described as “sisters-sites” (Straus & Otte, 2000), the recent reappraisal of their lithic industries, henceforth lead us to nuance this proposal. Our communication will therefore be the opportunity to shed a crossed look on two of the main gravettian sites of Belgium in the light of renewed data on their lithic assemblages, data that we will furthermore compare to the last results obtained on the Gravettian of Spy. New elements of reflection will in particular be proposed on the variability of technical behaviours within the Belgian Gravettian with tanged tools, as well as on the causes that may be responsible for this variability. Haesaerts P., Heinzelin J. de, 1979 – Le site paléolithique de Maisières-Canal, Brugge : De Tempel (Dissertationes Archaeologicae Gandenses, XIX), 119 p. Heinzelin J. de, 1973 – L’industrie du site paléolithique de Maisières-Canal, Brussels : Royal Belgian Institute of Natural Sciences (Mémoires, 171), 63 p. Otte M., 1979 – Le Paléolithique supérieur ancien en Belgique, Brussels : Royal Museums of Art and History (Monographies d'Archéologie nationales, 5), 684 p. Pesesse D., Flas D., 2014 – Wich Gravettians at Spy ?, in : Rougier H., Semal P., (eds.), Spy Cave. State of 120 years of pluridisciplinary research on the Betche-aux-Rotches from Spy (Jemeppe-sur-Sambre, Province of Namur, Belgium), Brussels : Royal Belgian Institute of Natural Sciences. Straus L. G., Otte M., 2000 – Résumé et conclusions, in : Straus L. G., Otte M., Haesaerts P. (dir.), La Station de l’Hermitage à Huccorgne. Un habitat à la frontière septentrionale du monde gravettien, Liège : Université de Liège (E.R.A.U.L., 94), pp. 209-213. Straus L. G., Otte M., Haesaerts P. (dir.), 2000 – La Station de l’Hermitage à Huccorgne, Liege : University of Liege (E.R.A.U.L., 94), 229 p. [less ▲]

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See detailModulated X-ray emission of the magnetic O8.5V-star Tr16-22
Nazé, Yaël ULg; Wade, Gregg A.; Petit, Véronique

in Astronomy and Astrophysics (2014), 569

Using an extensive X-ray dataset, we analyzed the X-ray emission of the massive O-star Tr16-22, which was recently found to be magnetic. Its bright X-ray emission is found to be modulated with a ~54 d ... [more ▼]

Using an extensive X-ray dataset, we analyzed the X-ray emission of the massive O-star Tr16-22, which was recently found to be magnetic. Its bright X-ray emission is found to be modulated with a ~54 d period. This timescale should represent the rotational timescale of the star, as it does for other magnetic massive stars. In parallel, new spectropolarimetric data confirm the published magnetic detection. Based on observations collected with the ESA science mission XMM-Newton, Chandra, and ESO-FORS2 instrument.Tables 1-3 are available in electronic form at <A href="http://www.aanda.org/10.1051/0004-6361/201424416/olm">http://www.aanda.org</A> [less ▲]

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See detailFraming and Political Discourse Analysis: Bush's Trip to Europe in 2005
Azpíroz Manero, María Luisa ULg

in Observatorio (OBS*) (2014), 8(3), 075-96

Framing empirical research analyzes the construction (frame building) and influence (frame effects) of the frames with which different social agents interpret and communicate reality. Based on Entman’s ... [more ▼]

Framing empirical research analyzes the construction (frame building) and influence (frame effects) of the frames with which different social agents interpret and communicate reality. Based on Entman’s (2004; 2008) and Kuypers’ (2008; 2009) contributions, this paper proposes and applies a qualitative methodology for the analysis of frame building in political discourse. It is located, therefore, on the strategic and methodological lines of framing research in political communication (Bartolomé; Rodríguez & Sádaba, 2012). As Kinder and Sanders state, frames are “invented and employed by political elites, often with an eye on advancing their own interests or ideologies, and intended to make favorable interpretations prevail” (Kinder & Sanders, 1990, p. 74). The paper includes a theoretical framework that reviews the evolution of framing literature in Communication, focusing especially on empirical studies. The contributions adopted for the elaboration of the methodology and the application process are explained in detail. The context of the case study, Bush’s discourse about the War on Terror on his trip to Europe in February 2005, is revised. Finally, the results obtained and the conclusions are detailed. [less ▲]

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See detailDroit électoral et principe d'égalité. L'élection des assemblées législatives nationales en droits allemand, belge et britannique
Bouhon, Frédéric ULg

Book published by Bruylant (2014)

The book concerns the election law and the equality principle in three European legal systems, i.e. the Federal Republic of Germany, the Kingdom of Belgium and the United Kingdom. In this framework, the ... [more ▼]

The book concerns the election law and the equality principle in three European legal systems, i.e. the Federal Republic of Germany, the Kingdom of Belgium and the United Kingdom. In this framework, the research is structured into two principal questions. I firstly wonder whether the election law guarantees equality among the governed people. Should the answer to that question be negative, I secondly check if the inequality can be legally justified in democratic systems. My thesis is a nuanced answer to these questions. The work shows that election law, considered under the scope of the equality principle, includes two categories of legislations which effect is opposed: some legal rules tend to distribute equally the faculty to influence the composition of the elected assemblies, while others tend to distribute unequally that faculty. Among the rules of the second category, I argue that the tendency to inequality can be partly legally justified by the purposes of these rules, but is also a mean – hardly justifiable in a democratic system – that helps persons and parties in government to remain in power. [less ▲]

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See detailCalibration of Building Simulation Models: Assessment of Current Acceptance Criteria
Ruiz Flores, Roberto ULg; Lemort, Vincent ULg

in Proceedings of the 8th International Conference Improving Energy Efficiency in Commercial Buildings (IEECB’14) (2014, September)

In this paper, the most used acceptance criteria in calibration of building simulation models are introduced and tried out by means of a practical exercise. In order to simplify the process of obtaining ... [more ▼]

In this paper, the most used acceptance criteria in calibration of building simulation models are introduced and tried out by means of a practical exercise. In order to simplify the process of obtaining “simulated data” and to avoid carrying out a formal calibration procedure; two yearly testing profiles (hourly time scale) are created from real building electrical metered data (¼ hour profile). Both testing profiles represent two model responses that could possibly be obtained in a common calibration procedure. The objective of this work is to test the capabilities of the method to determine (1) the model adequacy to represent an existing situation; (2) the reliability of the model when predicting a future or different scenario and also (3) the ability of the method to orient the practitioner to upgrade the model when it provides a non-satisfactory response. To do this, the real accuracy of both testing profiles is verified by means of a complementary statistical bin analysis. This crosschecking analysis allows highlighting the strengths and weakness of the current criteria and determining whether they need to be revised, modified or complemented. At the end of the analysis, it is concluded that the capabilities of the current acceptance criteria are limited because don’t provide any satisfactory answer, indication or clue for none of the three points aforementioned and some other complementary tests (such as bin analysis) must be implemented and performed in order to properly declare a model as calibrated. [less ▲]

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See detailMultilocus sequence typing analysis and antibiotic resistance of Clostridium difficile strains isolated from retail meat and humans in Belgium
Rodriguez Diaz, Cristina ULg; Taminiau, Bernard ULg; Avesani, Véronique et al

in Food Microbiology (2014), 42

Clostridium difficile has been isolated from food animals and meat, specially ground pork and ground beef. The recovered isolates were closely related to C. difficile human strains, indicating that ... [more ▼]

Clostridium difficile has been isolated from food animals and meat, specially ground pork and ground beef. The recovered isolates were closely related to C. difficile human strains, indicating that animals and food are possible transmission routes of human C. difficile infection. The main objective of this study was to characterize C. difficile isolates from retail meat and to compare with human isolates recovered from hospital patients in Belgium. Raw meat (beef and pork) was obtained from the retail trade. C. difficile was recovered from 2.3% of the beef samples and from 4.7% of the pork samples. A total of 4 different PCR-ribotypes were identified with a large percentage of types 078 and 014. Resistance to moxifloxacin and erythromycin was detected. The multi-locus sequence typing (MLST) analysis showed that meat and human isolates cluster in the same lineage. This study reveals the presence of toxigenic C. difficile in retail meat in Belgium with predominance PCR-ribotypes 078 and 014, which are among the four most prevalent ribotypes of C. difficile isolated from humans in Europe. [less ▲]

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See detailMeasurement uncertainty for persistent organic pollutants by isotope dilution mass spectrometry
Eppe, Gauthier ULg; Diletti, G; Fernandes, A et al

in Organohalogen Compounds (2014, September), 76

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See detailUne frontière comme lieu de mémoire : l'espace frontalier belgo-allemand
Brüll, Christoph ULg

Article for general public (2014)

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See detailSelecting job candidates who have a propensity to exhibit change-oriented organizational citizenship behaviour.
Lothe, Benoit ULg; Hansez, Isabelle ULg

Conference (2014, September)

Purpose An abundant literature indicates that Organizational Citizenship Behaviours (OCBs) positively influence a number of important organizational outcomes. Furthermore, research is needed on the topic ... [more ▼]

Purpose An abundant literature indicates that Organizational Citizenship Behaviours (OCBs) positively influence a number of important organizational outcomes. Furthermore, research is needed on the topic of assessing and selecting applicants who have a propensity to exhibit OCB (Organ & al., 2010). Some of these behaviours are truly important to enable organization to adapt and “to make constructive changes in the work and task environment” (Choi, 2007, p.468). Examples include Voice, a challenging dimension of OCB (Dominguez & al., 2013), and Sportsmanship, that facilitate the change by reducing the diversion of resources in trivial matters (Organ & al., 2006). This exploratory study provides empirical evidence about using Situational Judgment Tests (SJTs) for identifying applicants who have a propensity to exhibit change oriented OCB. Method Two SJTs were developed to comply with OCBs assessment. The OCBs framework includes behaviours relating to organizational adaptation (sportsmanship) and change (voice). OCBs were concurrently collected using self-reported measurement scales. Data were collected from 220 white collars and 139 university students through an online survey. Results Significant correlations were found between the SJT scores and overall OCB ratings. More specifics findings provided substantial evidence for the concurrent validity of the SJTs to measure change-oriented sub-dimensions of OCBs. Conclusions Researches on techniques to predict OCBs are scarce and this study is the first to address the development and validation of a SJT for the assessment of affiliative and challenging dimensions of OCBs. [less ▲]

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See detailPropriétés physico-chimiques et biologiques des substances humiques en relation avec le développement végétal
Tahiri, Abdelghani ULg; Destain, Jacqueline ULg; Druart, Philippe et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18(3), 436-445

Les substances humiques (SH) sont des composés organiques résultant de la transformation physique, chimique et microbiologique des résidus végétaux et animaux. Elles se retrouvent sous forme de ... [more ▼]

Les substances humiques (SH) sont des composés organiques résultant de la transformation physique, chimique et microbiologique des résidus végétaux et animaux. Elles se retrouvent sous forme de macromolécules carbonées hétérogènes et complexes dans tous les écosystèmes au niveau des sols ainsi que des sédiments, des eaux de surface et des lixiviats de décharges. Elles sont issues de processus d’humification déférents, générant ainsi des molécules variables et complexes composées principalement de carbone, d’hydrogène, d’oxygène, d’azote, de soufre et de groupements fonctionnels (COOH, OH, C=O). Ces substances sont connues pour influencer les propriétés du sol et interagir avec la croissance et le développement des plantes ou avec l’activité des microorganismes. L’influence de la croissance des plantes s’exprime généralement de manière directe via la stimulation des processus biochimiques et métaboliques ou indirecte via l’amélioration de la nutrition minérale. Mais, l’intensité de réponse reste dépendante de différents paramètres tels que l’origine, la nature de la matière organique initiale, les processus de transformation et la concentration des SH ainsi que des conditions expérimentales et des plantes traitées. Les mécanismes par lesquels les SH exercent leurs effets favorables sur les végétaux sont imprécis et généralement pas bien compris. [less ▲]

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