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See detailWritten Corrective Feedback: A Case Study
Noiroux, Kevin ULg

Conference (2015, July)

The present study looks at the efficacy of 3 types of written corrective feedback on errors made by French-Speaking High School students writing in English. More than 100 students, taught by 5 different ... [more ▼]

The present study looks at the efficacy of 3 types of written corrective feedback on errors made by French-Speaking High School students writing in English. More than 100 students, taught by 5 different teachers in 3 different schools, participated in the study. Each participant was randomly assigned to a different type of written corrective feedback: underlining, direct correct or explanation. Each time the students wrote a text in their EFL class, I (the researcher) corrected it, selected 10 errors and asked the students to state whether they understood the error. If they understood the error, they were asked to correct and/or explain it, depending on their treatment group. I then analyzed the corpus of more than 2000 errors: all the errors were categorized and the uptake moves (students’ corrections and explanations) verified. Finally, I checked whether there was a positive correlation between error types, types of corrective feedback, and students’ uptake. [less ▲]

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See detailQuasar radio polarizations align with large quasar group major axes
Pelgrims, Vincent ULg; Hutsemekers, Damien ULg

Poster (2015, July)

Using quasar polarizations and a sample of large quasar groups drawn from the SDSS DR7, we showed that at HIGH REDSHIFTS (z ~ 1.5) the spin axis orientations of black holes are correlated to the major ... [more ▼]

Using quasar polarizations and a sample of large quasar groups drawn from the SDSS DR7, we showed that at HIGH REDSHIFTS (z ~ 1.5) the spin axis orientations of black holes are correlated to the major axes of the groups to which they belong. Inside very rich groups the BH spins are aligned with the major axes. When the richness decreases, the spin axes become preferentially perpendicular. [less ▲]

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See detailEvaluation of phosphorus bioavailability according to the soil organic matter content
Barbieux, Sophie ULg; Colinet, Gilles ULg

Poster (2015, July)

Phosphorus (P) is an essential nutrient for plants. The organic matter contains significant amounts of P which can be mineralized and supply soil solution. We hypothesize that increasing P organic pools ... [more ▼]

Phosphorus (P) is an essential nutrient for plants. The organic matter contains significant amounts of P which can be mineralized and supply soil solution. We hypothesize that increasing P organic pools in soils is a way to improve its progressive release for plants and alleviate risks of immobilization in mineral forms. The main objective of this study is to evaluate the P bioavailability and its uptake by plants according to the soil organic matter (SOM) content. The experimental protocol is based on a micro-culture in pots. The test-plant used is ryegrass (Lolium perenne L.). Eight silty soils were selected from vegetable gardens (5) and from a long-term fertilization trial on field (3). They present a gradient of SOM (from 2 to 9 %) and available P content (from 5 to 55 mg/100g). Plants were first grown in pure sand and P-free Hoagland nutritive solution. Ten days after plant emergence, roots were brought into contact with the studied soil during about one month. The experiment was stopped after three harvests (every 10 days) and three growth cycles. At the end of the experimentation, analyses were performed on plant material (biomass, P content) and on soil (soluble P, available P, microbial P, pH, phosphatase activity, hot water carbon, nitrate). Besides this study, an incubation experiment was carried out with the same soils without plant to assess soil P status at each harvest time. Paper will present the main findings of the experiment. Especially, the following issues should find answers: (1) do higher levels of SOM and organic phosphorus modify the evolution of P content in soil solution and its uptake by plants?, (2) are the biological processes involved in P cycling promoted in soils with higher SOM content? [less ▲]

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See detailUrban biorefineries: a solution to manage and upgrade wastes in Wallonia ? Strategic aspects, proof-of-concept and industrial transfert
Richel, Aurore ULg

Scientific conference (2015, July)

“Urban biorefining” is an original concept aiming at using urban wastes (household wastes, municipal wastes, industrial liquid and/or solid residues and side-products, etc.), mainly of vegetal origin, for ... [more ▼]

“Urban biorefining” is an original concept aiming at using urban wastes (household wastes, municipal wastes, industrial liquid and/or solid residues and side-products, etc.), mainly of vegetal origin, for the production of an array of biofuels and bioproducts. This “urban biorefining” concept fits particularly with the economic, geographic and politic contexts and constraints of the Walloon Region (south part of Belgium). Indeed, Walloon Region is a very small territory (area of about 6,504 sq mi) with a temperate climate. Supply feedstock, mainly arising form forestry and agriculture, are thus rather restricted, submitted to importation, and subjected to non-standardized quality. Several examples of our regional strategy, still available on an industrial scale, are herein proposed and detailed. [less ▲]

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See detailiPot: Industrial Potato monitoring for the Belgian potato sector using remote sensing and crop growth modelling
Wellens, Joost ULg

in Qu, Dongyu (Ed.) Develop Together for a Better Future (2015 Beijing World Potato Congress) (2015, July)

The Belgian potato processing industry has known a spectacular growth during the last decades. The companies active in this sector (most of them family owned enterprises) have succeeded – together with ... [more ▼]

The Belgian potato processing industry has known a spectacular growth during the last decades. The companies active in this sector (most of them family owned enterprises) have succeeded – together with primary producers and traders – to grow from 500.000 tons of processed potatoes in 1990 till 3.650.000 tons of raw material in 2012. When considering the production (in tons) per habitant, Belgium is ranked on the 4th place with a production of 395 tons per 1.000 inhabitants. Nowhere in the world are higher yields obtained than in Belgium. To keep up its position on the forefront of innovation, the potato processing industries are continuously looking at promising novel technologies that could improve business processes at any stage of growth. The close follow up of parcels on the land as form above is becoming an important tool to improve the quantity and the quality of the potato crop, and reduce the risks in order to plan the storage, packaging or processing and as such to strengthen the competiveness of the Belgian potato in a global market. The iPot project, financed by the Belgian Science Policy Office (BELSPO), aims to provide the Belgian potato sector, represented by Belgapom, with near real time information on field condition (weather-soil) and crop development, and with early yield estimates, derived from a combination of satellite images and crop growth models. Satellite images are used since long for crop monitoring at regional level by the public sector. Traditionally, low to medium resolution images, with pixel sizes from 250m to 1km are used for providing information on crop growth and development, and on yield at regional scale. However, the recent launch of constellations of high resolution optical sensors (DMC, Sentinel-2) offering spatially detailed information (20m pixel size) at high frequency (every 2 to 3 days) and at low cost, is creating a (r)evolution in the world of crop monitoring. Automatic processing chains have been developed to derive vegetation indices (NDVI) and biophysical parameters (fAPAR, LAI, fCover). Maps are being derived on a regular basis with for each pixel the actual development stage of the potato crop. This on-line scanning of the growth (phenology) is expected to result in an increased performance of crop growth models and better yield predictions. Once the data for crop phenology are incorporated into the model (B-CGMS), the yield data collected at the parcel level will be assimilated into the model using optimization algorithms to minimize the discrepancies between observed and simulated yield time series in order to improve further yield estimations. The combination of these new earth observation and modelling techniques arose the interest of a new type of users, mainly from the private sector (agro-industry, agricultural insurers, etc.). The iPot project aims to bridge the gap between the latest research efforts regarding crop growth monitoring and the industry. An intuitive web based geo-information platform is being developed to allow both the Belgian potato industry and research centers to access, analyze and combine the data with their own field observations in closed collaboration with the farmers, for improved decision-making. [less ▲]

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See detailEffects of process water recycling during flotation of copper and cobalt oxidised ores from Luiswishi deposit in the Democratic Republic of Congo
Shengo, Michel; Gaydardzhiev, Stoyan ULg; Kalenga, Pierre

in Desalination and Water Treatment (2015), 55(7), 117

Laboratory flotation tests with copper–cobalt oxidized ore from the Luiswishi deposit in the Katanga province were done using process water being recycled to different degrees. Grade and recovery of ... [more ▼]

Laboratory flotation tests with copper–cobalt oxidized ore from the Luiswishi deposit in the Katanga province were done using process water being recycled to different degrees. Grade and recovery of copper and cobalt were followed by 10, 20 and 80% process to fresh water addition with the results from these conditions being compared to those without water recycling. When process water was recycled at 10%, 83.7% copper and 84.1% cobalt were recovered at the rougher stage bringing the cleaner stage to a concentrate with recovery of 53 and 60% for copper and cobalt, respectively. However, recycling process water, up to 20 and 80%, has reduced the recovery of copper in the final concentrate to 23 and 6%, respectively, and of cobalt to 46 and 27%, respectively. Monitoring of dissolved oxygen content, pulp pH and Es potential during flotation, coupled with thermodynamic estimation of the predominant chemical compounds in the system, has enabled to evaluate the effects on flotation from the undesirable compounds’ formation during process water recycling. DRIFT spectroscopy was used to identify the nature of the chemical compounds formed on malachite and heterogenite surface during their sulphidisation in the presence of thiosulphate ions. Thiosulphate ions depending on their concentration could promote or hinder malachite and heterogenite flotation by inducing changes in pulp physicochemical parameters or by altering mineral surface properties. [less ▲]

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See detailHousing Quality as Environmental Inequality: The Case of Wallonia, Belgium
Lejeune, Zoé ULg; Xhignesse, Guillaume ULg; Kryvobokov, Marko et al

in Journal of Housing and the Built Environment (2015)

First in the USA and then in many other countries, scholarship on environmental inequality has sought to shed light on the unequal environmental conditions borne by poor people and ethnic minorities, and ... [more ▼]

First in the USA and then in many other countries, scholarship on environmental inequality has sought to shed light on the unequal environmental conditions borne by poor people and ethnic minorities, and to challenge public policies and their unjust impacts on those target groups. Housing quality, especially the indoor characteristics of homes, offers an innovative perspective in this field of research. In previous research on environmental inequality in the Walloon context, housing quality has been proven to be a major determinant of quality of life and environmental well-being. This paper analyses housing quality through a twofold approach: through indoor characteristics on the one hand, and outdoor subjective and objective externalities on the other. It reveals the disparities between the most deprived and the wealthiest segments of the population. The evidence for this study is based on a housing quality survey carried out in 2012 and 2013 on 6,018 households in Wallonia (Belgium). The key findings are that poor people are found to live in housing of lower quality, in densely populated neighbourhoods and those with mixed use, with compensating amenities provided at the local level. Moreover, consistent with environmental inequality scholarship, deprived households are found to bear the burden of environmental degradation outside the home. People live in areas with poorer air quality, but are found to benefit from greater access to green spaces. The results of the survey reveal an interesting point concerning the environmental inequality literature; the interior features of housing are found to differ more widely between deprived and wealthier people than the surrounding environment does. [less ▲]

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See detailInfluence of soft ferromagnetic sections on the magnetic flux density profile of a large grain, bulk Y-Ba-Cu-O superconductor
Philippe, Matthieu ULg; Ainslie, Mark D; Wera, Laurent ULg et al

in Superconductor Science and Technology (2015), 28

Bulk, high temperature superconductors have significant potential for use as powerful permanent magnets in a variety of practical applications due to their ability to trap record magnetic fields. In this ... [more ▼]

Bulk, high temperature superconductors have significant potential for use as powerful permanent magnets in a variety of practical applications due to their ability to trap record magnetic fields. In this paper, soft ferromagnetic sections are combined with a bulk, large grain Y-Ba-Cu-O (YBCO) high temperature superconductor to form superconductor/ferromagnet (SC/FM) hybrid structures. We study how the ferromagnetic sections influence the shape of the profile of the trapped magnetic induction at the surface of each structure and report the surface magnetic flux density measured by Hall probe mapping. These configurations have been modelled using a 2D axisymmetric finite element method based on the H-formulation and the results show excellent qualitative and quantitative agreement with the experimental measurements. The model has also been used to study the magnetic flux distribution and predict the behaviour for other constitutive laws and geometries. The results show that the ferromagnetic material acts as a magnetic shield, but the flux density and its gradient are enhanced on the face opposite to the ferromagnet. The thickness and saturation magnetization of the ferromagnetic material are important and a characteristic ferromagnet thickness d* is derived: below d*, saturation of the ferromagnet occurs, and above d*, a weak thickness-dependence is observed. The influence of the ferromagnet is observed even if its saturation magnetization is lower than the trapped flux density of the superconductor. Conversely, thin ferromagnetic discs can be driven to full saturation even though the outer magnetic field is much smaller than their saturation magnetization. [less ▲]

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See detailExperimental and numerical study of the flight of geese
Dimitriadis, Grigorios ULg; Gardiner, James; Tickle, Peter et al

in Aeronautical Journal (2015), 119(1217), 1-30

The flight of barnacle geese at airspeeds representing high-speed migrating flight is investigated using experiments and simulations. The experimental part of the work involved the filming of three ... [more ▼]

The flight of barnacle geese at airspeeds representing high-speed migrating flight is investigated using experiments and simulations. The experimental part of the work involved the filming of three barnacle geese (Branta Leucopsis) flying at different airspeeds in a wind tunnel. The video footage was analysed in order to extract the wing kinematics. Additional information, such as wing geometry and camber was obtained from a 3D scan of a dried wing. An unsteady vortex lattice method was used to simulate the aerodynamics of the measured flapping motion. The simulations were used in order to successfully reproduce the measured body motion and thus obtain estimates of the aerodynamic forces acting on the wings. It was found that the mean of the wing pitch angle variation with time has the most significant effect on lift while the difference in the durations of the upstroke and downstroke has the major effect on thrust. The power consumed by the aerodynamic forces was also estimated; it was found that increases in aerodynamic power correspond very closely to climbing motion and vice versa. Root-mean-square values of the power range from 100 W to 240 W. Finally, it was observed that tandem flying can be very expensive for the trailing bird. [less ▲]

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See detailPromoting Competition at the Digital Age with an Application to Belgium
Copée, Pierre ULg; Gautier, Axel ULg; Lefevre, Mélanie ULg

E-print/Working paper (2015)

In this paper, we develop a fully-fledged postal market model to assess the extent of competition in the mail market in a context of declining mail volumes due to e-substitution. Our focus will be on the ... [more ▼]

In this paper, we develop a fully-fledged postal market model to assess the extent of competition in the mail market in a context of declining mail volumes due to e-substitution. Our focus will be on the Belgian market situation that is interesting for at least two reasons. First, the homogenous nature of the country implies that the extent of the entrant's market coverage will be either limited to the few very densely populated areas or large covering the whole country at the exception of the few very sparely populated areas. Second, because strong licensing requirements -including coverage constraints- are imposed on competing postal operators and they may constitute barrier to entry. Our model allows us to estimate the extent of entry, the cost of meeting the licensing requirements for potential entrants and the impact of entry on the cost of the universal service. [less ▲]

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See detailTravelling-wave ion mobility time-of-flight mass spectrometry as an alternative strategy for screening of multi-class pesticides in fruits and vegetables
Goscinny, Séverine ULg; Joly, Laure; De Pauw, Edwin ULg et al

in Journal of Chromatography. A (2015), 1405

This paper reports a novel approach to screening multi-class pesticides by ion mobility timeof- flight mass spectrometry detection. Nitrogen was selected as mobility gas. After optimization of the ... [more ▼]

This paper reports a novel approach to screening multi-class pesticides by ion mobility timeof- flight mass spectrometry detection. Nitrogen was selected as mobility gas. After optimization of the different ion mobility parameters, determination of matrix effect on the drift times was conducted using different matrix extracts. The results showed that drift time values are not influenced by the matrix and also are independent of the concentration within the working range for 100 pesticides tested, making drift time a powerful additional identification tool. Based on statistics, 2% variation criteria provides a good fit for all the pesticides targeted, and could be considered as a maximum acceptable criteria associated with the drift time parameter for identification purpose. This 2% value is in agreement with already reported criteria, for instance, for GC or LC retention time in European documents. Finally, the well-known feature of mobility to separate complex mixtures was also tested to obtain purified extracted mass spectra of pesticides in fruit extract. [less ▲]

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See detailCROSSROADS le magazine sonore des musiques africaines-américaines
Sacré, Robert ULg

Diverse speeche and writing (2015)

Magazine hebdomaire et sonore des Musiques Africaines-Americaines podcasts: www.mixcloud.com/robertsacre9 infos: page Facebook www.facebook.com/robert.sacre.9

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See detailSketch-based and parametric modeling: Association of two-externalization processes for early daylight optimization
Gallas, Mohamed Anis ULg; Delfosse, Vincent ULg

(2015, July)

This paper focuses on sketch-based and parametric modeling as two externalization devices used in architectural design practice. The first part of this paper addresses features and ability of these ... [more ▼]

This paper focuses on sketch-based and parametric modeling as two externalization devices used in architectural design practice. The first part of this paper addresses features and ability of these externalization tools to support design activities during the early design steps. The second part proposes an association process of a sketch-based modeling tool (SketSha-Archi®) and a parametric modeling tool (Grasshopper®) to create an advanced process for daylight optimization. The process aimed to associate the hand-sketching freedom with the precise exploration functions of digital tools (parametric modeling and evaluation tools). [less ▲]

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See detailAre there different analysis paterns when people assess rural landscapes?
Vanderheyden, Vincent ULg; Schmitz, Serge ULg

in Firmino, Ana (Ed.) Book of Abstracts and Programme: 23rd Annual Colloquium on Sustainable Rural Systems: Smart Answers for a smiling future (2015, July)

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See detailMaking "Place" count in Risk perception studies
Ocampo, Lou Angeli ULg; Schmitz, Serge ULg

in Firmino, Ana (Ed.) Book of Abstracts and Programme: 23rd Annual Colloquium on Sustainable Rural Systems: Smart Answers for a smiling future (2015, July)

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See detailIdesbald Goddeeris, La Grande Emigration polonaise en Belgique (1831-1870). Elites et masses en exil à l’époque romantique, Francfort-sur-le-Main, P.I.E. Peter Lang, 2013, 552 p.
Genin, Vincent ULg

in Bulletin d'Information de l'Association Belge d'Histoire Contemporaine = Mededelingenblad van de Belgische Vereniging voor Nieuwste Geschiedenis (2015), XXXVII(2), 18-19

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See detailPhotocatalytic Oxidative Treatment of Waste Water contamined with Pharmaceutical Products
Vreuls, Christelle; Wilmot, Annick; Cludts, Marc et al

Poster (2015, July)

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See detailWe forgot to pay attention to ordinary tourism! A call to revise the research agenda for rural tourism
Schmitz, Serge ULg; Crozat, Dominique

in Firmino, Ana (Ed.) Book of Abstracts and Programme: 23rd Annual Colloquium on Sustainable Rural Systems: Smart Answers for a smiling future (2015, July)

This paper aims to suggest a new research agenda for rural tourism, including for a smiling future for the countryside, in reversing the current trend to distinguish the destination, to aim at ... [more ▼]

This paper aims to suggest a new research agenda for rural tourism, including for a smiling future for the countryside, in reversing the current trend to distinguish the destination, to aim at supersegmentation of tourism and to target a cultural, elitist, tourism. Indeed most tourist activities can be done and are done in a relative vicinity, by ordinary tourists aiming to have a good time. Moreover, the countryside does not always offer extraordinary sights that attract people from the whole continent. We argue that there should be a place and more attention for ordinary tourism development. By ordinary tourism, we do not mean mass tourism but just the fact that some people spent a few days away from home. We do not want to reject the appealing concepts of cultural tourism, ecotourism, adventure tourism, ethnic tourism, gastronomic tourism, farm tourism and so on. We just want to be realistic and call to rethink the importance of ordinary tourism and its current challenges: facing new ways of traveling (e.g. Low cost), of buying vacation (e-commerce), of enjoying holidays (more frequently/with friends, alone or with the family/ being active or passive). [less ▲]

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See detailOne-year follow-up of platelet-rich plasma infiltration to treat chronic proximal patellar tendinopathies
Kaux, Jean-François ULg; Bruyère, Olivier ULg; Croisier, Jean-Louis ULg et al

in Acta Orthopaedica Belgica (2015), 81(2), 251-256

Infiltration of Platelet-Rich Plasma (PRP) may be considered as a recent therapeutic option for chronic tendinopathies. The aim of this study is to evaluate the clinical status and the return to sports ... [more ▼]

Infiltration of Platelet-Rich Plasma (PRP) may be considered as a recent therapeutic option for chronic tendinopathies. The aim of this study is to evaluate the clinical status and the return to sports activities in patients with chronic proximal patellar tendinopathies. Twenty subjects with chronic proximal patellar tendinopathy benefited from 1 infiltration of PRP coupled with a standardized eccentric rehabilitation. The follow-up (up to 1 year) was assessed by means of a Visual Anologue Scale (VAS), the International Knee Documentation Committee (IKDC) form and the Victorian Institute of Sport Assessment (VISA-P) score. Moreover, subjects had to answer an information questionnaire concerning their life and sports activities. Seventy percents of the patients reported a favourable evolution with decrease of pain, and returned to sports activities. With time, VAS dropped significantly and both IKDC and VISA-P scores improved also significantly. This study confirms that a local injection of PRP coupled with a program of eccentric rehabilitation for treating a chronic jumper’s knee, improves pain symptoms and the functionaliti [less ▲]

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