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See detailChallenges of Sustainable and Commercial Aquaponics
Goddek, Simon; Delaide, Boris ULg; Mankasingh, Utra et al

in Sustainability (2015), 7

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See detailImproved spectral fitting of nitrogen dioxide from OMI in the 405-465 nm window
van Geffen, J H G M; Boersma, K F; Van Roozendael, M et al

in Atmospheric Measurement Techniques (2015), 8

An improved nitrogen dioxide (NO2) slant column density retrieval for the Ozone Monitoring Instrument (OMI) in the 405–465 nm spectral region is presented. Since the launch of OMI on board NASA’s EOS-Aura ... [more ▼]

An improved nitrogen dioxide (NO2) slant column density retrieval for the Ozone Monitoring Instrument (OMI) in the 405–465 nm spectral region is presented. Since the launch of OMI on board NASA’s EOS-Aura satellite in 2004, differential optical absorption spectroscopy (DOAS) retrievals of NO2 slant column densities have been the starting point for the KNMI DOMINO and NASA SP NO2 vertical column data as well as the OMI NO2 data of some other institutes. However, recent intercomparisons between NO2 retrievals from OMI and other UV/Vis and limb spectrometers, as well as ground-based measurements, suggest that OMI stratospheric NO2 is biased high. This study revises and, for the first time, fully documents the OMI NO2 retrieval in detail. The representation of the OMI slit function to convolve high-resolution reference spectra onto the relevant spectral grid is improved. The window used for the wavelength calibration is optimised, leading to much-reduced fitting errors. Ozone and water vapour spectra used in the fit are updated, reflecting the recently improved knowledge of their absorption cross section in the literature. The improved spectral fit also accounts for absorption by the O2–O2 collision complex and by liquid water over clearwater areas. The main changes in the improved spectral fitting result from the updates related to the wavelength calibration: the RMS error of the fit is reduced by 23% and the NO2 slant column by 0.85 1015 molec cm-2, independent of latitude, solar zenith angle and NO2 value. Including O2–O2 and liquid water absorption and updating the O3 and water vapour cross-section spectra further reduces NO2 slant columns on average by 0.35 1015 molec cm-2, accompanied by a further 9% reduction in the RMS error of the fit. The improved OMI NO2 slant columns are consistent with independent NO2 retrievals from other instruments to within a range that can be explained by photochemically driven diurnal increases in stratospheric NO2 and by small differences in fitting window and approach. The revisions indicate that current OMI NO2 slant columns suffered mostly from an additive positive offset, which is removed by the improved wavelength calibration and representation of the OMI slit function. It is therefore anticipated that the improved NO2 slant columns are most important to retrievals of spatially homogeneous stratospheric NO2 rather than to heterogeneous tropospheric NO2. [less ▲]

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See detailA novel procedure to measure shrinkage-free tree-rings from very large wood samples combining photogrammetry, high-resolution image processing, and GIS tools
Latte, Nicolas ULg; Beeckman, Hans; Bauwens, Sébastien ULg et al

in Dendrochronologia (2015)

We present a new procedure for wood sampling and tree-ring measurement that can be used for dendrochronological investigation on very large trees, specifically adapted for tropical rainforest species ... [more ▼]

We present a new procedure for wood sampling and tree-ring measurement that can be used for dendrochronological investigation on very large trees, specifically adapted for tropical rainforest species. This procedure takes advantage of the technological developments in computing, image processing, and geographic information systems (GIS) to overcome the technical limitations of the currently used methods. Two types of wood samples can be used (stem disks and/or bars) depending on tree diameter, and the difficulty of ring delineation and crossdating. Bars are an effective compromise between cores and disks. We developed an application combining several programs (Excel, R, ArcGIS, and MapWinGIS) in the Windows operating system for semi-automatic measurement of tree-rings from high-resolution images of the sanded cross-section. Using an innovative method to reverse the wood shrinkage resulting from the drying process, tree-ring measurement can be performed on shrinkage-free images, thus referring to the actual growth of the tree. [less ▲]

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See detailScrivere il compromesso intorno al 1965
Curreri, Luciano ULg

Article for general public (2015)

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See detailTree models with Scikit-Learn: Great models with little assumptions
Louppe, Gilles ULg

Conference (2015, April 03)

This talk gives an introduction to tree-based methods, both from a theoretical and practical point of view. It covers decision trees, random forests and boosting estimators, along with concrete examples ... [more ▼]

This talk gives an introduction to tree-based methods, both from a theoretical and practical point of view. It covers decision trees, random forests and boosting estimators, along with concrete examples based on Scikit-Learn about how they work, when they work and why they work. [less ▲]

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See detailNotizie dalla letteratura sicitaliana, ovvero siciliana e italiana (ed europea)
Curreri, Luciano ULg

Article for general public (2015)

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See detailBibliométrie et Open Access à l'ULg
Thirion, Paul ULg

Scientific conference (2015, April 01)

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See detailOptimal Enforcement of Competition Policy: The Commitments Procedure under Uncertainty
Gautier, Axel ULg; Petit, Nicolas ULg

E-print/Working paper (2015)

Since the introduction of a commitments procedure in EU antitrust policy (Article 9 of Council Regulation 1/2003), the European Commission has extensively settled cases of alleged anticompetitive ... [more ▼]

Since the introduction of a commitments procedure in EU antitrust policy (Article 9 of Council Regulation 1/2003), the European Commission has extensively settled cases of alleged anticompetitive practices. In this paper, we use a formal model of law enforcement (Bebchuk, 1984; Shavell, 1988) to identify the optimal procedure to resolve cases in a context of uncertainty related to the law (L-uncertainty) and to the facts (F-uncertainty). We show that commitments are suboptimal when L-uncertainty is high. Furthermore, the generalized use of commitments creates an additional risk of under-enforcement when F-uncertainty is significant. [less ▲]

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See detailThe International Journal of Educational Organization and Leadership
Noiroux, Kevin ULg

in The International Journal of Educational Organization and Leadership (2015), 21.5

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See detailTracking Middleboxes in the Mobile World with TraceboxAndroid
Thirion, Valentin; Edeline, Korian ULg; Donnet, Benoît ULg

in 7th International Workshop on Traffic Monitoring and Analysis (TMA) (2015, April)

Middleboxes are largely deployed over cellular networks. It is known that they might disrupt network performance, expose users to security issues, and harm protocols deployability. Further, hardly any ... [more ▼]

Middleboxes are largely deployed over cellular networks. It is known that they might disrupt network performance, expose users to security issues, and harm protocols deployability. Further, hardly any network measurements tools for smartphones are able to infer middlebox behaviors, specially if one cannot control both ends of a path. In this paper, we present TraceboxAndroid a proof-of-concept measurement application for Android mobile devices implementing the tracebox algorithm. It aims at diagnosing middlebox-impaired paths by detecting and locating rewriting middleboxes. We analyze a dataset sample to highlight the range of opportunities offered by TraceboxAndroid. We show that TraceboxAndroid can be useful for mobile users as well as for the research community. [less ▲]

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See detailThe words of prevention, part II: ten terms in the realm of quaternary prevention
Jamoulle, Marc ULg; Gavilan, Enrique; Cardoso, Raquel Val et al

in Revista Brasileira de Medicina de Família e Comunidade (2015)

ABSTRACT Objective: This part II article about the ‘words of prevention’ presents in a terminological way the content of ten current concepts used in the prevention domain which are closely linked to ... [more ▼]

ABSTRACT Objective: This part II article about the ‘words of prevention’ presents in a terminological way the content of ten current concepts used in the prevention domain which are closely linked to quaternary prevention: (1) overinformation, (2) overdiagnosis, (3) medically unexplained symptoms, (4) overmedicalisation, (5) incidentaloma, (6) overscreening, (7) overtreatment, (8) shared decision making, (9) deprescribing, and (10) disease mongering. Methods: with the support of the laboratory team of the University of Rouen, France, which is dedicated to medical terminology and semantic relationships, it was possible to utilize a graphic user interface (called DBGUI) allowing the construction of links for each of chosen terms, and making automatic links to MeSH, if any. Those concepts are analyzed in their environment in current literature, as well as in their MeSH counterparts, if any, and related semantic online terminologies. Results and Discussion: The rules in terminological development aspire to cover the whole field of a concept and in the meantime, it helps to avoid the noise due to proxy and not exactly related issues. This refers to exhaustivity and specificity in information retrieval. Our finds show that referring to MeSH only in information retrieval in General Practice/Family medicine can induce much noise and poor adequacy to the subject investigated. Conclusion: Gathering concepts in specially prepared terminologies for further development of ontologies is a necessity to enter in the semantic web area and the era of distributed data. [less ▲]

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See detailConvention relative à la réhabilitation du Saumon atlantique dans le bassin de la Meuse (Rapport 2014-2015)
Ovidio, Michaël ULg; Dierckx, Arnaud ULg; Benitez, Jean-Philippe ULg et al

Report (2015)

Le présent rapport d’activités intègre les travaux des deux équipes universitaires de Namur et de Liège dans la cadre de la convention relative à la réhabilitation du saumon atlantique dans le bassin de ... [more ▼]

Le présent rapport d’activités intègre les travaux des deux équipes universitaires de Namur et de Liège dans la cadre de la convention relative à la réhabilitation du saumon atlantique dans le bassin de la Meuse au cours de la période février 2014- janvier 2015 [less ▲]

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See detailThe words of prevention, part I: changing the model
Jamoulle, Marc ULg; Gavilan, Enrique; Cardoso, Raquel Val et al

in Revista Brasileira de Medicina de Família e Comunidade (2015)

ABSTRACT Objective: This part I article explores the different meanings of relevant keywords for General Practice/Family Medicine (GP/FM) in the prevention domain. The aim is to contribute to information ... [more ▼]

ABSTRACT Objective: This part I article explores the different meanings of relevant keywords for General Practice/Family Medicine (GP/FM) in the prevention domain. The aim is to contribute to information process in GP/FM by keeping in line with the main terms used in health care organization. Methods: Important keywords for GP/FM in the prevention domain were selected. Then, a search was carried out on the main sources in GP/FM databases, as well as in Medical Subject Heading and major terminological databases available online. Results and Discussion: There is discrepancy between the conceptual contents of major prevention models amongst the usual bibliographic sources of knowledge in GP/FM in particular and medicine in general. Conclusion: For GP/FM, distribution of preventive activities is now firmly established on a new constructivist model, privileging the doctor-patient relationships and introducing a cybernetic thinking on the health care activities with a special commitment to ethics and the positive duty of beneficence. [less ▲]

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See detailPrevenção quaternária: primeiro não causar dano - Editorial
Jamoulle, Marc ULg

in Revista Brasileira de Medicina de Família e Comunidade (2015)

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See detailQuaternary prevention: first, do not harm - Editorial
Jamoulle, Marc ULg

in Revista Brasileira de Medicina de Família e Comunidade (2015)

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See detailManuels de langues et risques d'inégalités
Simons, Germain ULg; Delbrassine, Daniel ULg; Van Hoof, Florence ULg

in Didactiques en pratique (2015), (1),

Dans cet article synthétique, les auteurs relèvent quelques caractéristiques de certains manuels de langues contemporains et démontrent en quoi celles-ci présentent des risques d'inégalités pour les ... [more ▼]

Dans cet article synthétique, les auteurs relèvent quelques caractéristiques de certains manuels de langues contemporains et démontrent en quoi celles-ci présentent des risques d'inégalités pour les apprenants [less ▲]

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See detailEditorial du n°1 de la revue "Didactiques en pratique"
Simons, Germain ULg; Beckers, Jacqueline ULg; Poffé, Corentin ULg

in Didactiques en pratique (2015)

Ce premier éditorial de la nouvelle revue du Cifen :"Didactique en pratique" présente le contenu de ce numéro et propose une mise en perspective théorique de la problématique abordée lors de l'Université ... [more ▼]

Ce premier éditorial de la nouvelle revue du Cifen :"Didactique en pratique" présente le contenu de ce numéro et propose une mise en perspective théorique de la problématique abordée lors de l'Université d'été 2014 : "Outils didactiques et (in)égalités". Ce premier numéro est principalement consacré à la publication des Actes de l'Université d'été 2014, mais il évoque aussi la première journée de rencontre officielle entre le Cifen et les maitres de stages. [less ▲]

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See detailMise en perspective de l'après-midi de rencontre avec les maîtres de stages du Cifen
Simons, Germain ULg

in Didactiques en pratique (2015), 1

Ce texte est le discours du Président du Cifen qui a été prononcé à l'occasion de la première journée officielle de rencontre entre le Centre et les maitres de stages (5 novembre 2014). Ce discours ... [more ▼]

Ce texte est le discours du Président du Cifen qui a été prononcé à l'occasion de la première journée officielle de rencontre entre le Centre et les maitres de stages (5 novembre 2014). Ce discours succinct reprend la question qui a servi de fil rouge à cette journée : "Comment collaborer efficacement pour accompagner au mieux nos stagiaires ?" et en détaille chaque composante. [less ▲]

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See detailDoes the soil’s effective hydraulic conductivity adapt in order to obey the Maximum Entropy Production principle? A lab experiment
Westhoff, Martijn ULg; Zehe, Erwin; Erpicum, Sébastien ULg et al

Conference (2015, April)

The Maximum Entropy Production (MEP) principle is a conjecture assuming that a medium is organized in such a way that maximum power is subtracted from a gradient driving a flux (with power being a flux ... [more ▼]

The Maximum Entropy Production (MEP) principle is a conjecture assuming that a medium is organized in such a way that maximum power is subtracted from a gradient driving a flux (with power being a flux times its driving gradient). This maximum power is also known as the Carnot limit. It has already been shown that the atmosphere operates close to this Carnot limit when it comes to heat transport from the Equator to the poles, or vertically, from the surface to the atmospheric boundary layer. To reach this state close to the Carnot limit, the effective thermal conductivity of the atmosphere is adapted by the creation of convection cells (e.g. wind). The aim of this study is to test if the soil’s effective hydraulic conductivity also adapts itself in such a way that it operates close to the Carnot limit. The big difference between atmosphere and soil is the way of adaptation of its resistance. The soil’s hydraulic conductivity is either changed by weathering processes, which is a very slow process, or by creation of preferential flow paths. In this study the latter process is simulated in a lab experiment, where we focus on the preferential flow paths created by piping. Piping is the process of backwards erosion of sand particles subject to a large pressure gradient. Since this is a relatively fast process, it is suitable for being tested in the lab. In the lab setup a horizontal sand bed connects two reservoirs that both drain freely at a level high enough to keep the sand bed always saturated. By adding water to only one reservoir, a horizontal pressure gradient is maintained. If the flow resistance is small, a large gradient develops, leading to the effect of piping. When pipes are being formed, the effective flow resistance decreases; the flow through the sand bed increases and the pressure gradient decreases. At a certain point, the flow velocity is small enough to stop the pipes from growing any further. In this steady state, the effective flow resistance of the sand bed will be compared with the theoretical optimal flow resistance obtained with the MEP principle. For this study, different magnitudes of the forcing will be tested, while also the effect of dry spells will be explored. [less ▲]

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