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See detailUse of high performance computing in animal breeding
Vandenplas, Jérémie ULg; Gengler, Nicolas ULg

in Book of Abstracts of the 65th Annual Meeting of the European Federation of Animal Science (2014)

High-perfomance computing facilities proposing shared-memory and distributed-memory multiprocessors are becoming available. With those clusters, parallel computing could lead to increased performances and ... [more ▼]

High-perfomance computing facilities proposing shared-memory and distributed-memory multiprocessors are becoming available. With those clusters, parallel computing could lead to increased performances and problem sizes. However, to our knowledge and especially for variance components estimations, most software available in animal breeding, based on sparse matrices computations, do not allow parallel computing and are limited by memory accessible by the central processing unit, or allow parallel computing only for options with dense matrices computations, which limits anyway problem sizes due to storage of dense matrices. The aim was to propose simple and effective modifications for the BLUPF90 family of programs to reduce computing time with consideration of required memory. Modifications were based on academic free packages proposing solver and sparse inversion for sparse symmetric indefinite linear systems. First, modifications concerned the sparse inversion subroutine implemented in the package FSPAK. Rearrangements of 'do' loops to allow optimizations of computer operations by some compilers and addition of OpenMP directives were performed. The ordering operation was modified to more easily compare a multiple minimum degree algorithm (MMD; implemented in FSPAK) and a multilevel nested dissection algorithm (implemented in METIS 4.0.3). Second, the package PARDISO Version 5.0.0 was used instead of FSPAK. This package proposes in particular a parallel solver and sparse inversion on shared-memory multiprocessors. Modified FSPAK and PARDISO were compared to original FSPAK using MMD through REMLF90. Different models, such as univariate or bivariate (random regressions) test-day animal and single-step genomic models, were tested. All jobs were run 5 times. With an appropriate ordering algorithm, speedup for each REMLF90 iteration were up to 7.5 for modified FSPAK and up to 22.8 for PARDISO with 2 threads. With 4 threads, speedup increased to 8.3 and 32.5, respectively. [less ▲]

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See detailImages et rôles du professeur de langues dans le cadre de la mondialisation. Le cas de la mobilité étudiante européenne
Defays, Jean-Marc ULg; Meunier, Deborah ULg

in Bento, Margaret; Spaëth, Valérie (Eds.) Contexte global et contextes locaux : tensions, convergences et enjeux en didactique des langues (2014)

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See detailValidation of differential drag propellantless maneuvers using 6 DoF simulations and stochastic dynamics
Dell'Elce, Lamberto ULg; Kerschen, Gaëtan ULg

in Proceedings of the 9th International ESA Conference on Guidance, Navigation & Control Systems (2014)

Differential drag is regarded as a promising technique in low-Earth orbits, since it allows to turn the often-undesired drag perturbation into a control force for relative maneuvers. Nonetheless, relevant ... [more ▼]

Differential drag is regarded as a promising technique in low-Earth orbits, since it allows to turn the often-undesired drag perturbation into a control force for relative maneuvers. Nonetheless, relevant uncertainties in drag modeling make its practical realization a challenge, especially if no other propulsive means is available to accommodate them. The main outcome of this study is the identification and characterization of the uncertainty sources affecting differential-drag-based maneuvers. This characterization is carried out by using statistical methods in conjunction with mechanical modeling considerations to infer a probabilistic model of the sources from observed data. The developments are illustrated in the framework of the QARMAN mission through high-fidelity simulations involving coupled attitude and orbital dynamics. [less ▲]

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See detailÉtalement urbain et vulnérabilité croissante face au risque d’inondation : l’exemple de Nouakchott (Mauritanie)
Ozer, Pierre ULg; Ould Sidi Cheikh, Mohamed Ahmed; Ozer, André ULg

in Ozer, André; Ozer, Pierre (Eds.) Colloque International "La Géographie Physique et les Risques Naturels" - Livre de résumés (2014)

Après la sécheresse et la désertification qui ont fortement frappé la Mauritanie dans les années 1970 et 1980, la ville de Nouakchott a connu un développement démographique spectaculaire. En effet, la ... [more ▼]

Après la sécheresse et la désertification qui ont fortement frappé la Mauritanie dans les années 1970 et 1980, la ville de Nouakchott a connu un développement démographique spectaculaire. En effet, la population de la capitale mauritanienne est passée de 134 704 habitants en 1977 à 899 887 habitants recensés en mars 2013. Depuis 2000, Nouakchott voit sa population augmenter de 125 personnes par semaine ; une croissance absolue jamais atteinte par le passé. La ville s'est donc agrandie considérablement et les nouveaux arrivants ont construit leurs maisons dans des zones marginales sans aménagement préalable. Plusieurs quartiers se sont installés soit dans des zones dépressionnaires à sols salés sous forme de sebkha, soit dans des zones dunaires fortement ensablées. [less ▲]

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See detailEosinophilic Bronchopneumopathy
Clercx, Cécile ULg

in Proceedings 35 Internationaler Fortbildungskurs Kleintierkrankheiten (2014)

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See detailFirst assessment of the impacts of Saharan dust events on the respiratory health in West Africa: A case study in the Northern Benin
De Longueville, Florence ULg; Henry, Sabine; Ozer, Pierre ULg

in Belviso, Claudia; Fiore, Saverio; Giannossi, Maria Luigia (Eds.) DUST2014 - International Conference on Atmospheric Dust _ Book of Abstracts (2014)

More than 50% of the global dust emitted into the atmosphere comes from the Sahara. About 60% of the Saharan dust move southwards to the Gulf of Guinea (Engelstaedter et al., 2006). Once in the air, these ... [more ▼]

More than 50% of the global dust emitted into the atmosphere comes from the Sahara. About 60% of the Saharan dust move southwards to the Gulf of Guinea (Engelstaedter et al., 2006). Once in the air, these dust contribute to increase the concentrations of particles smaller than 10 microns (PM10), which are respirable particles (Ozer et al. 2005). A number of adverse health effects have been associated with desert dust, including respiratory diseases (Goudie, 2014). [...] [less ▲]

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See detailAnalytic Model for The Motion About An Oblate Planet in The Presence Atmospheric Drag
Martinusi, Vladimir ULg; Dell'Elce, Lamberto ULg; Kerschen, Gaëtan ULg

in Advances in The Astronautical Sciences (2014)

The paper introduces a new model for the motion about an oblate planet under the influence of the atmospheric drag. Both qualitative and quantitative insights are revealed, as well as closed-form ... [more ▼]

The paper introduces a new model for the motion about an oblate planet under the influence of the atmospheric drag. Both qualitative and quantitative insights are revealed, as well as closed-form equations of motion. The main tool consists in averaging the effects of both perturbations (oblateness and drag), and deriving the variational equations for the vectorial orbital elements. The model is singularity-free and may serve as an initial guess for control problems, as well as an analytic propagator. [less ▲]

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See detailCharacterization of Particle Damage and Surface Exposure of a Copper Ore Processed by Jaw Crusher, HPGR and Electro-dynamic Fragmentation
Da Fonseca Martins Gomes, Otavio ULg; Monteiro de Oliveira, Debora; Santos Sobral, Luis Gonzaga et al

in Carpenter, John; Bai, Chenguang; Hwang, Jiann-Yang (Eds.) Characterization of Minerals, Metals, and Materials 2014 (2014)

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See detailImpacts des récentes variations pluviométriques sur le droit du sol, l’accès a l’eau et l’agriculture en Mauritanie : l’exemple du lac de Mâle
Gassani, Jean; De Longueville, Florence ULg; Gemenne, François ULg et al

in Camberlin, Pierre; Richard, Yves (Eds.) Actes du 27e Colloque International de l'Association Internationale de Climatologie (2014)

The Islamic Republic of Mauritania is at a socio-political crossroads in its history. Environmental crises coupled with the transformation of economic activities and population pressures disrupt social ... [more ▼]

The Islamic Republic of Mauritania is at a socio-political crossroads in its history. Environmental crises coupled with the transformation of economic activities and population pressures disrupt social structures of the country. The drought that began in 1970 has transformed the nomadic lifestyle, forcing them to settle. This deeply changed tribes’ perception access to land and water resources, and has led to increased pressure on the Haratines (former black slaves) in agricultural production. With the release of human rights, the enactment of a land law, and taking into account the Sharia, former slaves claimed their ownership of the land they cultivated. The refusal of the latter to access their application, the Haratines headed for land undeveloped and interfered in the customary practice of the management of water catchments. The latent conflict escalated into open in the watershed of Lake Mâle. Today, the situation does not improve since the political will collides with local tribal authorities. [less ▲]

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See detailRégner en mode épistolaire : l’exemple de Charles VIII
Dumont, Jonathan ULg; Marchandisse, Alain ULg

in Dumézil, Bruno; Vissière, Laurent (Eds.) Épistolaire politique I. Gouverner par les lettres (2014)

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See detailÉvolution récente des précipitations de mars-mai en Afrique de l'Est: configurations spatiales et évolution sub-saisonnière
Philippon, Nathalie; Camberlin, Pierre; Moron, Vincent et al

in Camberlin, Pierre; Richard, Yves (Eds.) Actes du 27e Colloque International de l'Association Internationale de Climatologie (2014)

Using raingauge daily rainfall data documenting the Horn of Africa and the Long Rains over the period 1961-2012, the aim of this study is three-fold:1/ confirming the drying trend detected by Lyon et ... [more ▼]

Using raingauge daily rainfall data documenting the Horn of Africa and the Long Rains over the period 1961-2012, the aim of this study is three-fold:1/ confirming the drying trend detected by Lyon et DeWitt (2012) during the Long Rains using gridded rainfall, 2/ understanding how this drying is expressed at the intraannual time scale using the sub-seasonal scenario approach developed by Moron et al. (2013) and 3/ assess its impact on vegetation. A drying is actually measured using raingauge data but is less severe than the one measured using gridded data. It is the strongest at the driest stations and during the rainfall climatological peak (April). It seems to be associated with a higher frequency of the dry subseasonal scenarios i.e. characterized by negative rainfall anomalies through the whole or the core of the seasonal cycle. But we don't observe yet a diminution of the vegetation photosynthetic activity in response to the rainfall decrease. To the contrary, the Rainfall Use Efficiency (RUE) displays a slightly positive trend. [less ▲]

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See detailSaharan dust: An under-studied but significant source of air pollution in West Africa
Ozer, Pierre ULg; De Longueville, Florence ULg

in Belviso, Claudia; Fiore, Saverio; Giannossi, Maria Luigia (Eds.) DUST2014 - International Conference on Atmospheric Dust _ Book of Abstracts (2014)

Recently, the World Health Organization’s International Association for Research on Cancer (IARC) classified outdoor air pollution as carcinogenic to humans and now puts air pollution in the same category ... [more ▼]

Recently, the World Health Organization’s International Association for Research on Cancer (IARC) classified outdoor air pollution as carcinogenic to humans and now puts air pollution in the same category as tobacco smoke, UV radiation and plutonium. Exposure to ambient fine particles was recently estimated to have contributed 3.2 million premature deaths worldwide in 2010. The ambient air across the globe is polluted by emissions from motor vehicles, industrial processes, power generation, household combustion of solid fuel, and other sources. Dust storms lead to particulate levels that exceed internationally recommended levels especially in West Africa but this source of air pollution is under-studied, particularly in the literature devoted to human health impacts. [less ▲]

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See detailQuantifier la charge de travail chez le jeune rugbyman? Pourquoi? Comment?
Paulus, Julien ULg; Laly, Arnaud

in Rassemblement National des Préparateurs Physiques (2014)

La prévention du dépassement (over-reaching) ou tout du moins sa détection précoce est capitale dans le processus d'entrainement compte-tenu de ses effets négatifs sur la performance. L'individualisation ... [more ▼]

La prévention du dépassement (over-reaching) ou tout du moins sa détection précoce est capitale dans le processus d'entrainement compte-tenu de ses effets négatifs sur la performance. L'individualisation de la planification des entrainements rugbystiques et physiques est nécessaire pour ne pas dépasser la charge de travail préalablement identifiée comme optimale pour chaque joueur. En effet, en institutionnalisant les cycles de récupération et de repos relatif, comme nous le réalisions auparavant, la charge réelle n'était pas prise en compte mais bien la charge théorique prévue par la planification. A cette charge de travail du centre de formation, viennent s'ajouter celle du club d'appartenance de chaque joueur mais aussi celle des différentes équipes nationales… Les disparités entre les joueurs en terme de charge de travail et donc de fatigue apparaissent rapidement sans compter les joueurs qui sont blessés et/ou en période de réathlétisation! La difficulté pour nous était d'identifier le moment opportun pour proposer des phases de récupération dans le respect du joueur, de son développement à long terme mais aussi dans notre tâche d'améliorer sa performance. [less ▲]

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See detailMILLI-INTERACTING DARK MATTER AND THE DIRECT-SEARCH EXPERIMENTS
Wallemacq, Quentin ULg

in Rencontres de Moriond 2014 : cosmology (2014)

Hydrogen-like dark atoms interact with standard matter because of two mixings, a kinetic mixing between standard photons and dark massless photons and a mass mixing of sigma mesons and dark scalars. After ... [more ▼]

Hydrogen-like dark atoms interact with standard matter because of two mixings, a kinetic mixing between standard photons and dark massless photons and a mass mixing of sigma mesons and dark scalars. After having thermalized in terrestrial matter, they reach underground detectors with thermal energies and form bound states with atoms in the active media, which causes the emission of photons that produce the observed signals. The model explains well the positive results from DAMA/LIBRA and CoGeNT without any contradiction with the null results from XENON100, LUX, CDMS-II/Ge and superCDMS. [less ▲]

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See detailA Fast Newton-Raphson Method in Stochastic Linearization
Canor, Thomas ULg; Blaise, Nicolas ULg; Denoël, Vincent ULg

in Proceedings of the Ninth International Conference on Structural Dynamics (2014)

Owing to its accessible implementation and rapidity, the equivalent linearization has become a common probabilistic approach for the analysis of large-dimension nonlinear structures, as encountered in ... [more ▼]

Owing to its accessible implementation and rapidity, the equivalent linearization has become a common probabilistic approach for the analysis of large-dimension nonlinear structures, as encountered in earthquake and wind engineering. It consists in replacing the nonlinear system by an equivalent linear one, by tuning the parameters of the equivalent system, in order to minimize some discrepancy error. Consequently classical analysis tools such as the spectral analysis may be reconditioned to approximate the solution of structures with slight to moderate nonlinearities. The tuning of the equivalent parameters requires the solution of a set of nonlinear algebraic equations involving integrals. It is typically performed with the fixed-point algorithm, which is known to behave poorly in terms of convergence. We therefore advocate for the use and implementation of a Newton-Raphson approach, which behaves much better, even in its dishonest formulation. Unfortunately, this latter option requires the costly construction of a Jacobian matrix. In the approach described in this paper, this issue is answered by introducing a series expansion method that provides a fast and accurate estimation of the residual function (whose solution provides the equivalent parameters) and a fast and approximate estimation of the Jacobian matrix. An illustration demonstrate the good accuracy obtained with the proposed method. [less ▲]

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See detailAssessing the Probability of Training Image-Based Geological Scenarios Using Geophysical Data
Hermans, Thomas ULg; Caers, Jef; Nguyen, Frédéric ULg

in Pardo-Iguzquiza, Eulogio; Guardiola-Albert, Carolina; Heredia, Javier (Eds.) et al Mathematics of Planet Earth - Proceedings of the 15th Annual Conference of the International Association for Mathematical Geosciences (2014)

In multiple-point statistics (MPS), the construction of training im-ages (TIs) is one of the most critical steps. Reliable geological studies may not always be available to depict with certainty what ... [more ▼]

In multiple-point statistics (MPS), the construction of training im-ages (TIs) is one of the most critical steps. Reliable geological studies may not always be available to depict with certainty what geological patterns or heterogeneity are present. In this context, geophysical techniques may provide additional information to reduce the possible large uncertainty in the understanding of prior geological scenarios. To overcome this problem, we developed a methodology to verify the consistency of geophysical data with independently-built TIs representing different plausible geological scenarios. If a TI is deemed consistent with the field geophysical survey, then in a sec-ond step we calculate a likelihood probability for each consistent TI. Our methodology starts by creating subsurface models with each TI. From these models we create synthetic geophysical data and from this synthetic data, synthetic inverted models. These models are now compared with a single inverted model obtained from the field sur-vey, allowing for our definition of what is “consistent”. To that ex-tent, we calculate the Euclidean distance between any two inverted models as well as field data and visualize the results in a 2D or 3D space using multidimensional scaling (MDS). With this technique, it is possible to verify if field cases fall in the distribution represented by synthetic cases, and thus are consistent with them. In a second step, we present a cluster analysis on the MDS-map to highlight which parameters are the most sensitive for the construction of TI. Based on this analysis, a probability of each geological scenario is computed through kernel smoothing of the densities in reduced pro-jected metric space. This approach was tested using electrical resistivity tomography as geophysical data to analyze TI scenarios for the Meuse alluvial aqui-fer (Belgium), where the lack of reliable sedimentological data lead to the definition of a multitude of geological scenarios, hence TIs. [less ▲]

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See detailInteger Programs with Prescribed Number of Solutions and a Weighted Version of Doignon-Bell-Scarf’s Theorem
Aliev, Iskander; De Loera, Jesus; Louveaux, Quentin ULg

in Lee, Jon; Vygen, Jens (Eds.) Proceedings of the 17th IPCO (2014)

In this paper we study a generalization of the classical fesibility problem in integer linear programming, where an ILP needs to have a prescribed number of solutions to be considered solved. We first ... [more ▼]

In this paper we study a generalization of the classical fesibility problem in integer linear programming, where an ILP needs to have a prescribed number of solutions to be considered solved. We first provide a generalization of the famous Doignon-Bell-Scarf theorem: Given an integer k, we prove that there exists a constant c(k, n), depending only on the dimension n and k, such that if a polyhedron {x : Ax ≤ b} contains exactly k integer solutions, then there exists a subset of the rows of cardinality no more than c(k,n), defining a polyhedron that contains exactly the same k integer solutions. The second contribution of the article presents a structure theory that characterizes precisely the set Sg≥k (A) of all vectors b such that the problem Ax = b, x ≥ 0, x ∈ Zn , has at least k-solutions. We demonstrate that this set is finitely generated, a union of translated copies of a semigroup which can be computed explicitly via Hilbert bases computation. Similar results can be derived for those right-hand-side vectors that have exactly k solutions or fewer than k solutions. Finally we show that, when n, k are fixed natural numbers, one can compute in polynomial time an encoding of Sg≥k(A) as a generating function, using a short sum of rational functions. As a consequence, one can identify all right-hand-side vectors that have exactly k solutions (similarly for at least k or less than k solutions). Under the same assumptions we prove that the k-Frobenius number can be computed in polynomial time. [less ▲]

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See detailCompatibility of using TiO2 and the faecal near-infrared reflectance spectrometry for estimation of cattle intake
Vandermeulen, Sophie ULg; Decruyenaere, Virginie; Ramirez-Restrepo, Carlos Alberto et al

in Hopkins, A; Collins, RP; Fraser, MD (Eds.) et al EGF at 50: the future of European Grasslands. Proceedings of the 25th General Meeting of the European Grassland Federation, Aberystwyth, Wales, U.K., 7 - 11th September 2014 (2014)

Combining titanium dioxide (TiO2) as indigestible marker to faecal near-infrared reflectance spectrometry (F-NIRS) can be used to determine cattle feed intake and quality of ingested forage if F-NIRS ... [more ▼]

Combining titanium dioxide (TiO2) as indigestible marker to faecal near-infrared reflectance spectrometry (F-NIRS) can be used to determine cattle feed intake and quality of ingested forage if F-NIRS spectra are not modified by the marker. This study aimed at determining the compatibility of TiO2 with F-NIRS. Three dry cows were fed a standard hay-based diet for three weeks supplemented with a daily dose of 0.1 % (10g) TiO2 during the last two weeks of the experiment. Faeces samples were collected every day and analysed for TiO2 and F-NIRS. Results suggest that TiO2 did not interfere with F-NIRS analyses. The calculations of crude protein, NDF, ADL contents, as well as dry matter intake did not change over time with increasing TiO2 in the faeces (P > 0.05). Slight differences observed for other predicted parameters seemed to be independent from TiO2. The higher Mahalanobis distance (H) for chemical composition (H = 7.2) independent from TiO2 inclusion could indicate that faecal spectra did not correspond exactly to the prediction database. Although 0.1% incorporation of TiO2 seem not to interfere with F-NIRS measurements, caution must be taken with higher levels of TiO2 as nothing indicates that interference could not appear. [less ▲]

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See detailBi-stable flow fields and two-way couplings between flow and sedimentation in shallow reservoirs
Dewals, Benjamin ULg; Peltier, Yann ULg; Pirotton, Michel ULg et al

in 3rd IAHR Europe Congress, Book of Proceedings, Porto, Portugal, 14-16 April 2014 (2014)

Shallow reservoirs are structures commonly used in civil and environmental engineering. Recent experimental and numerical research has focused on the velocity fields and sediment deposits in rectangular ... [more ▼]

Shallow reservoirs are structures commonly used in civil and environmental engineering. Recent experimental and numerical research has focused on the velocity fields and sediment deposits in rectangular shallow reservoirs. These analyses highlighted the existence of fascinating complex flow fields and sedimentation patterns, involving bi-stable flow fields and significant two-way couplings between flow and sedimentation in such reservoirs. We review here the findings of the latest research and present on-going developments. [less ▲]

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See detailBelgian mud mounds, facies and structure and stromatoporoid fauna
Da Silva, Anne-Christine ULg; Kershaw, S.; Boulvain, Frédéric ULg et al

in Wesenberg Lauridsen, b.; Bjerager, M. (Eds.) Cold water carbonates at high paleolatitudes from the Palaeozoic to the Reent – combining outcrops studies with core studies and geophysical imaging. Programme and abstract book (2014)

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See detailInfluence of microfabric evolution on the retention behaviour of compacted clayey soils
Dieudonné, Anne-Catherine ULg; Della Vecchia, Gabriele; Charlier, Robert ULg et al

in Khalili, Nasser; Russel, Adrian; Khoshghalb, Arman (Eds.) Unsaturated Soils: Research and Applications (2014)

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See detailThe Horn of Africa, the Factors of a Unity. Wars, Cultures and Imperialisms (19-20th centuries)
Genin, Vincent ULg

in Literatures of the Horn of Africa (Ethiopia, Eritrea, Somalia, Djibouti) : Beyond the Language and the Territory (2014)

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See detailNonlinear generalization of Den Hartog's equal peak method for nonlinear primary systems
Habib, Giuseppe ULg; Detroux, Thibaut ULg; Kerschen, Gaëtan ULg

in Proceedings of the International Conference on Structural Nonlinear Dynamics and Diagnosis (2014)

This study addresses the mitigation of one problem nonlinear resonance of a mechanical system. In view of the narrow bandwidth of the classical linear tuned vibration absorber, a new nonlinear absorber ... [more ▼]

This study addresses the mitigation of one problem nonlinear resonance of a mechanical system. In view of the narrow bandwidth of the classical linear tuned vibration absorber, a new nonlinear absorber, termed the nonlinear tuned vibration absorber (NLTVA), is introduced in this paper. One unconventional aspect of the NLTVA is that the mathematical form of its restoring force is tailored according to the nonlinear restoring force of the primary system. The NLTVA parameters are then determined using a nonlinear generalization of Den Hartog's equal-peak method. The mitigation of the resonant vibrations of a Duffing oscillator is considered to illustrate the proposed developments. [less ▲]

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See detailRéalisation d’un inventaire typologique et dendrochronologique des charpentes anciennes en région Bruxelles-Capitale
Weitz, Armelle ULg; Charruadas, Paulo ULg; Crémer, Sarah et al

in Chronique, Archaeologia Mediaevalis 37, Namur, 13-14 mars 2014 (2014)

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See detailHydration kinetics of compacted low-density bentonite
Dieudonné, Anne-Catherine ULg; Romero, Enrique; Charlier, Robert ULg

in Khalili, Nasser; Russel, Adrian; Khoshghalb (Eds.) Unsaturated Soils: Research and Applications (2014)

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See detailRepresentations for Cross-task, Cross-object Grasp Transfer
Hjelm, Martin; Detry, Renaud ULg; Ek, Carl Henrik et al

in IEEE International Conference on Robotics and Automation (2014)

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See detailÜber Möglichkeiten und Grenzen des Kulturtransfers. Günter Grass im Gespräch mit seinen Übersetzern
Letawe, Céline ULg

in Pasewalck, Silke (Ed.) "Interkulturalität und (literarisches) Übersetzen". Wechselwirkungen zwischen Literaturwissenschaft und Translatologie. (2014)

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See detailBronze Age Domestic Architecture in Eastern Syria : Familiar, Social and Economic Implications
Mas, Juliette ULg

in Bieliński, P.; et al. (Eds.) Proceedings of the 8th International Congress on the Archaeology of the Ancient Near East, 30 April – 4 May 2012, University of Warsaw, Volume 1: Plenary Sessions, Township and Villages, High and Low – The Minor Arts for the Elite and for the Populace (2014)

This paper deals with a PhD project on domestic architecture and society on the Syrian Euphrates region and in the Jezirah during the Bronze Age. The large geographical and chronological framework allowed ... [more ▼]

This paper deals with a PhD project on domestic architecture and society on the Syrian Euphrates region and in the Jezirah during the Bronze Age. The large geographical and chronological framework allowed to collect an important corpus of houses. The analysis of statistical data on their different features allowed interpretations, in particular concerning their functionnal characteristics. The attention is here focused on the crafts and industrial production of the house inhabitants. The contemporary economic system is well known in Southern Mesopotamia, and was there mainly based on official oikoi linked to the temples or to the palace. On the contrary, the analysis of Northern Mesopotamian evidence shows that the economic system in this area was mainly based on private households, the state control probably being there of lesser importance. [less ▲]

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See detailShape Optimization of Interior Permanent Magnet Motor for Torque Ripple Reduction
Kuci, Erin ULg; Geuzaine, Christophe ULg; Dular, Patrick ULg et al

in Proceedings of The 4th International Conference on Engineering Optimization: Lisbon (Portugal), 8-11 September 2014 (2014)

The objective of the paper is to present an open source environment to perform the design, simulation (Gmsh, GetDP) and optimization (OpenOpt) of electrical machines. The design of the permanent magnets ... [more ▼]

The objective of the paper is to present an open source environment to perform the design, simulation (Gmsh, GetDP) and optimization (OpenOpt) of electrical machines. The design of the permanent magnets of a v-shaped interior permanent magnet machine is then considered. The later is modeled using the finite element method with a formulation based on the magnetic vector potential. Optimization is based on mathematical programming approach. A semi-analytical sensitivity analysis is compared with the finite difference. Thanks to this approach, the design time is much shorter than that required by an approach of trial and error used by industry. The reduction of the torque ripple is about 70 \% with respect to the original design. [less ▲]

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See detaileLearning COLEACP : un dispositif de formation au service des professionnels du secteur agricole en Afrique
Prunier, Emmanuelle; Le Hung, Florian; Schiffers, Bruno ULg

in ELearning Africa 2014 - Book of Abstracts (2014)

Le dispositif de formation à distance du COLEACP (Comité de Liaison Europe-Afrique-Caraïbes-Pacifique) est une composante d'un système complet de formation dédié au renforcement des capacités des ... [more ▼]

Le dispositif de formation à distance du COLEACP (Comité de Liaison Europe-Afrique-Caraïbes-Pacifique) est une composante d'un système complet de formation dédié au renforcement des capacités des opérateurs des filières agricoles des pays ACP (Afrique Caraïbes et Pacifique). [less ▲]

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See detailEvolution of clay fabric and water retention properties along hydromechanical stress paths
Dieudonné, Anne-Catherine ULg; Charlier, Robert ULg; Levasseur, Séverine ULg et al

in Numerical Methods in Geotechnical Engineering (2014)

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See detailL'art de la guigne en 1862. Contexte, intertexte et sous-texte du Guignon de Mallarmé
Durand, Pascal ULg

in Brissette, Pascal; Luneau, Marie-Pier (Eds.) Deux siècles de malédiction littéraire (2014)

Deuxième texte en vers publié par Mallarmé, dans la revue L'Artiste, alors dirigée par Arsène Houssaye, qui n’en retint que les cinq premiers tercets, Le Guignon place l’entrée de son auteur dans le champ ... [more ▼]

Deuxième texte en vers publié par Mallarmé, dans la revue L'Artiste, alors dirigée par Arsène Houssaye, qui n’en retint que les cinq premiers tercets, Le Guignon place l’entrée de son auteur dans le champ poétique sous le signe d’une malédiction d’aspect très convenu, tant y paraît bien saturé l’appareil des clichés assimilant élection poétique et ratage social. La banalité du propos, gage donné aux pairs d’une adhésion fervente aux normes à quoi la plupart d’entre eux se rangent au milieu du Second Empire, y prend cependant une tournure assez singulière, témoignant d’un jeu avec les codes autant que d’une soumission à ceux-ci. Ce jeu passe par un complexe montage intertextuel articulant, au registre de la malédiction poétique, les apports d’un Nerval, d’un Gautier, d’un Baudelaire et d’un Cladel ; il passe aussi par une tonalité grotesque et paroxystique, reflet d’une distance prise à l’égard de l’imaginaire collectif ainsi synthétisé et d’une extériorisation critique de structures littéraires puissamment incorporées, au prix d’un point de vue tout ensemble interne et externe pris sur ces structures. Texte fondamentalement trivial — à tous les sens du terme —, Le Guignon tient ainsi, à la fois, de la récitation d’un credo et d’une sorte de physiologie des poètes post-romantiques. [less ▲]

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See detailDynamic Modeling andControl System Definition for a Micro-CSP Plant Coupled with Thermal Storage Unit
Ireland, Melissa; Orosz, Matthew; Brisson, John et al

in Proceedings of TurboExpo 2014 (2014)

Organic Rankine cycle (ORC) systems are gaining ground as a means of effectively providing sustainable energy. Coupling small-scale ORCs powered by scroll expander-generators with solar thermal collectors ... [more ▼]

Organic Rankine cycle (ORC) systems are gaining ground as a means of effectively providing sustainable energy. Coupling small-scale ORCs powered by scroll expander-generators with solar thermal collectors and storage can provide combined heat and power to underserved rural communities. Simulation of such systems is instrumental in optimizing their control strategy. However, most models developed so far operate at steady-state or focus either on ORC or on storage dynamics. In this work, a model for the dynamics of the solar ORC system is developed to evaluate the impact of variable heat sources and sinks, thermal storage, and the variable loads associated with distributed generation. This model is then used to assess control schemes that adjust operating conditions for daily environmental variation. [less ▲]

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See detailEtat du droit belge avant la tempête Salduz
Jacobs, Ann ULg

in Jacobs, Ann; Fourment, Françoios (Eds.) La garde à vue. Regards croisés belges, français et européens (2014)

Etat de la législation belge en ce qui concerne l'assistance de l'avocat lors des premiers interrogatoires avant la jurisprudence et la la loi Salduz.

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See detailLe double jeu libertin : du jeu de Blaise Pascal aux Considérations politiques sur les coups d’État de Gabriel Naudé
Decoster, Sara ULg

in Küpper, Achim; Vanden Berghe, Kristine (Eds.) Guerre et jeu : perspectives transversales sur un sujet historique, artistique et culturel à l'époque moderne (2014)

Dans cette conférence, nous nous proposons de déceler les éléments ludiques dans les Considérations politiques sur les coups d’estat (1639) de Gabriel Naudé. Pour ce faire, nous essaierons d’abord de ... [more ▼]

Dans cette conférence, nous nous proposons de déceler les éléments ludiques dans les Considérations politiques sur les coups d’estat (1639) de Gabriel Naudé. Pour ce faire, nous essaierons d’abord de dresser une anthropologie du jeu, sur base des travaux de J. Huizinga et R. Caillois, avant de rejoindre la philosophie wittgensteinienne sur le sujet. Le travail de Naudé étant fortement marqué par son contexte historique, nous avons effectué un rapprochement avec la théorie du divertissement de Pascal, telle que celle-ci apparaît dans les Pensées. Cet examen s’appuie notamment sur les Commentaires d'Henri Gouhier et sur les analyses de Colas Duflo (Le jeu : de Pascal à Schiller). De cette théorie du jeu découle une vision politique très particulière, théorisée par Christian Lazzeri et Gérard Ferreyrolles. La politique est le jeu destiné à organiser la société terrestre, où la loi s’appuie sur la force. Ces idées sont poussées à leur paroxysme dans les Considérations politiques sur les coups d’estat naudéennes. A travers l’exemple du massacre de la Saint-Barthélemy, que Naudé décrit, nous pouvons dégager en quoi consiste le jeu de Naudé : il s’agit d’un espace réglé, qui ne se définit toutefois qu’à posteriori. Le hasard et l’aspect jouissif du secret jouent un rôle important dans la pensée de Naudé. Ainsi se développe un jeu de rôles étrange entre les différents acteurs : le souverain, le peuple, et le philosophe. Les règles du jeu se complexifient, et, finalement, la position des différents pions sur l’échiquier ne sera plus très claire. Cette duplicité est caractéristique du libertinage, dont Naudé est un représentant important. [less ▲]

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See detailDurability of hydrophobic treatments on concrete monuments
Courard, Luc ULg; Lucquiaud, Vincent ULg; Gérard, Olivier et al

in Proceedings of 7th International Conference on Water Repellent Treatment and Protective Surface Technology for Building Materials (2014)

The protection of concrete historical structures is a challenge for the coming years. Hydrophobic treatment may induce a delay in degradations progress as well as a protection against water penetration ... [more ▼]

The protection of concrete historical structures is a challenge for the coming years. Hydrophobic treatment may induce a delay in degradations progress as well as a protection against water penetration. Existing products - mainly silane and siloxane based – have been submitted to different ageing processes including UV radiation, moistening cycles, thermal shocks, freeze-thaw cycles, carbonation and efficiency has been evaluated on the base of contact angle, vapour and chloride permeability and, capillarity absorption. Investigation results clearly show a good behaviour of hydrophobic treatments under main ageing conditions. [less ▲]

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See detailA LARGE STRAIN ELASTO-VISCOPLASTIC NUMERICAL MODEL
Careglio, Claudio; Canales Cardenas, Cristian ULg; Ribero, Melisa et al

in Bustamante, Roger (Ed.) Proceedings of PACAM XIV (2014)

A large strain elasto-viscoplastic Perzyna model was proposed by Ponthot. The resultant numerical model computes the elastic response using an hypoelastic model. A viscoplastic multiplier was proposed ... [more ▼]

A large strain elasto-viscoplastic Perzyna model was proposed by Ponthot. The resultant numerical model computes the elastic response using an hypoelastic model. A viscoplastic multiplier was proposed, then both inviscid (elastoplastic) and elastic limiting cases can be easily recovered. More recently the authors have included this viscoplastic model in a large strain constitutive model based on hyperelasticity and multiplicative decomposition of deformation gradient tensor. In this work a brief summary of both, hypoelastic and hyperelastic based large strain models of viscoplasticity is provided. Large strain examples are simulated in order to test the discussed models. Different parameters of the constitutive model are tested in order to study the sensitivity of the resultant algorithm. From the obtained results can be said that both models show a very good agree and represent very well the characteristic of the viscoplastic constitutive model. [less ▲]

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See detailSécheresse, migration et vulnérabilité à Djibouti-Ville
Ozer, Pierre ULg; Mahamoud, Ayan; Nour Ayeh, Moustapha et al

in Ozer, André; Ozer, Pierre (Eds.) Colloque International "La Géographie Physique et les Risques Naturels" - Livre de résumés (2014)

Ces dernières décennies, l’Afrique de l’Est souffre d’une longue et lente détérioration pluviométrique. De 2007 à 2011, la ville de Djibouti a enregistré un déficit de 73% des précipitations moyennes ... [more ▼]

Ces dernières décennies, l’Afrique de l’Est souffre d’une longue et lente détérioration pluviométrique. De 2007 à 2011, la ville de Djibouti a enregistré un déficit de 73% des précipitations moyennes annuelles par rapport à la moyenne de 30 ans (1981-2010). Cette sécheresse sans précédent va mettre de nombreuses familles des zones rurales (de Djibouti, d’Ethiopie et de Somalie) sur la route. Cette migration a pour point de chute la ville de Djibouti où des quartiers neufs se créent, comme Buldhuqo. Totalement inexistant en 2004, il explose après 2009. Les derniers arrivants s’installent dans le fond de l’oued, là même où la zone était inondée en 2004 et 2009 suite à des pluies courtes mais intenses. La prochaine pluie extrême, l’exposition de ces populations précaires aux risques hydrologiques sera maximale. Cette analyse montre que le déficit pluviométrique actuel est exceptionnel et historiquement unique. Les migrations importantes de population induites par cette sécheresse vers la ville de Djibouti doivent être encadrées, notamment lors de leur installation spontanée. Il est nécessaire de diminuer l’exposition aux risques hydrologiques de ces populations sinistrées, pour que les victimes de la sécheresse ne soient pas emportées par un excès pluviométrique. [less ▲]

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See detailIl latino dell'Alcestis di Barcellona
Macedo, Gabriel ULg

in Molinelli, Piera; Cuzzolin, Pierluigi; Fedriani, Chiara (Eds.) Latin Vulgaire Latin Tardif X. Actes du Xe Colloque international sur le latin vulgaire et tardif (2014)

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See detail"Je n'aime pas mon accent américaine": quelle culture discursive pour quelle conscience normative chez les étudiants Erasmus?
Meunier, Deborah ULg

in Dervin, Fred; Machart, Régis (Eds.) Les nouveaux enjeux des mobilités et migrations académiques (2014)

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See detailEarly Jezirah 3b Pottery from Tell Beydar, Selected Inventories from latest excavation campaigns
Mas, Juliette ULg; Gavagnin, Katia

in Bieliński, P.; et al. (Eds.) Proceedings of the 8th International Congress on the Archaeology of the Ancient Near East, 30 April – 4 May 2012, University of Warsaw, Volume 2: Excavation and Progress Reports, Posters (2014)

Since 1992, excavations at Tell Beydar have offered the opportunity to explore an urban centre of the Upper Khabur region. The extensive exploration of the EJZ 3b levels gave us access to the urbanism and ... [more ▼]

Since 1992, excavations at Tell Beydar have offered the opportunity to explore an urban centre of the Upper Khabur region. The extensive exploration of the EJZ 3b levels gave us access to the urbanism and the architecture of the city as well as its material culture, especially the pottery. The assemblages presented in this paper were exclusively found directly on the floors of various buildings (of a public, domestic, religious, offi- cial nature) and inside a grave. Most of these inventories consist of complete vessels discovered either intact or smashed but restorable. The aim of this paper is to investigate if, or to what extent, the intra-site distribution of the morphological repertoire of Beydar IIIb ceramic is related to its context of use. [less ▲]

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See detailLe corps du Prince. La perception de l'Egypte ancienne
Winand, Jean ULg

in Marchandisse, Alain (Ed.) Le corps du Prince (2014)

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See detailDétermination des propriétés de couches minces dans le béton à l’aide d’un géoradar commercial à hautes fréquences: approche pic-à-pic et analyse fréquentielle du coefficient de réflexion
Van der Wielen, Audrey; Courard, Luc ULg; Nguyen, Frédéric ULg

in Balayssac, Jean-Paul (Ed.) Compte-rendus de Diagnobeton 2014 (2014)

The Ground Penetrating Radar (GPR) is an efficient tool for the non-destructive inspection of concrete structures. It is widely used for the detection of rebars or humid zones or for evaluating the ... [more ▼]

The Ground Penetrating Radar (GPR) is an efficient tool for the non-destructive inspection of concrete structures. It is widely used for the detection of rebars or humid zones or for evaluating the thickness of elements. But when an element contains a thin layer, the radar waves are submitted to multiple reflections on the interfaces and the layer appears in the radargram as a single reflection, whose detailed analysis can allow determining the thickness and the permittivity of the thin layer. Two approaches were considered in this paper. In the first one, the analysis is based on the peak-to-peak reflection amplitude. The second approach uses a frequency analysis of the reflection coefficient, whose amplitude and phase can then be calculated for several frequencies. With this method, the thickness and permittivity of the layer can in theory be simultaneously determined. Both methods were numerically validated through finite difference simulations and experimentally tested on concrete samples containing an air layer of variable thickness. We showed that the frequency analysis allowed to reach a higher precision in the parameters estimation for a limited additional computing cost. The method efficiency depends on the conditions and is optimal for layers with a high permittivity presenting a large contrast with the matrix. [less ▲]

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See detailImpact de l’érosion littorale sur les migrations forcées. Cas de Cotonou, Bénin.
Ozer, Pierre ULg; Hountondji, Yvon-Carmen; Bessan, Modestine Victoire et al

in Ozer, André; Ozer, Pierre (Eds.) Colloque International "La Géographie Physique et les Risques Naturels" - Livre de résumés (2014)

En utilisant la fonction multi dates disponible dans Google Earth, cet article estime la superficie érodée à Cotonou entre 2002 et 2011 à l’est de l’exutoire du Lac Nokoué. En outre, il évalue le nombre ... [more ▼]

En utilisant la fonction multi dates disponible dans Google Earth, cet article estime la superficie érodée à Cotonou entre 2002 et 2011 à l’est de l’exutoire du Lac Nokoué. En outre, il évalue le nombre de maisons détruites ainsi que le nombre de personnes contraintes à une migration forcée. Les figures sont importantes puisque de l’ordre de cent mètres de zone côtière ont totalement disparu en une décennie sur un tronçon de près de six kilomètres de long en pleine ville ou en proche périphérie. [less ▲]

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See detailInvestigation of pregnancy-associated glycoproteins (PAGs) by means of an enzymoimunoassay (ELISA) sandwich kit for pregnancy monitoring in sheep
El Amiri, Bouchra; Delahaut, Philippe; Colemans, Yves et al

in Chentouf, M; López-Francos, A; Bengoumi, M (Eds.) et al Options méditerranéennes : Series A (2014)

The aim of the present study was to investigate the use of a PAGs ELISA-Sandwich kit (Ret. code E.G.7. CER. Marloie, Belgium) for both early pregnancy diagnosis (in Sardi sheep) and the pregnancy follow ... [more ▼]

The aim of the present study was to investigate the use of a PAGs ELISA-Sandwich kit (Ret. code E.G.7. CER. Marloie, Belgium) for both early pregnancy diagnosis (in Sardi sheep) and the pregnancy follow up (in Boujaâd and Boujaâd x D'man sheep). ln Sardi breed, plasma samples were obtained from pregnant ewes (n = 17) from day 18 to 30 of gestation at 2 days interval. ln Boujaâd (n = 8) and Boujaâd x D'man (n = 20) the blood samples were weekly collected from the first week of gestation till the 4th week after lambing. The PAG concentrations were determined by a sandwich-ELISA based on purified bovine PAG (boPAG-67 kDa) as a standard, the antiserum raised against caprine PAG (caPAG-55+62 kDa) as a capture antibody (1/40000) and antiserum raised against purified PAG from buffalo (AS 859) as detection antibody (1/32 000). The Avidin-HRP and TMB were used to reveal reactions. Ewes were assumed to be pregnant when PAG concentrations were higher than 0.8 ng/ml. Results showed that in Sardi sheep it is possible to detect ail ewes as pregnant as early as on 24 days of gestation. ln Boujaâd and Boujaâd x D'man the PAG concentrations reached the higher values just before lambing. This value is higher in ewes carrying more than one lamb than in those carrying a single lamb. To conclude, the present study shows that the ELISA kit used for early pregnancy diagnosis in sheep as weil as for pregnancy fellow up could be a good alternative to the radioimmunoassay RIA in countries where this last technique is hard to set up. [less ▲]

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See detailEstetrol and neuroprotection against perinatal ischemic insult
Tskitishvili, Ekaterine ULg; Nisolle, Michelle ULg; Noël, Agnès ULg et al

in Estetrol attenuates neonatal hypoxic-ischemic brain injury (2014)

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See detailEvaluation of the mechanical integrity of a concrete surface by means of combined destructive methods
Courard, Luc ULg; Bissonnette, Benoît; Garbacz, Andrzej et al

in Grantham, Michael (Ed.) Proceedings of the 5th International Conference on Concrete Repair (2014)

As a tight bond between the repair and the old concrete is required, the soundness of the prepared surface has to be carefully assessed. This paper presents the results of an investigation intended to ... [more ▼]

As a tight bond between the repair and the old concrete is required, the soundness of the prepared surface has to be carefully assessed. This paper presents the results of an investigation intended to assess and compare quantitatively different test methods, namely the Schmidt rebound hammer, the pull-out test and the pull-off test, to evaluate superficial mechanical integrity of a substrate after concrete removal operations. Although it does not yield a precise evaluation of compressive strength, the Schmidt rebound hammer test is recognized as a useful tool for performing quick surveys to assess concrete uniformity. The pull-off test is very well correlated with the splitting-tensile test, but it is not suited for vertical and overhead surfaces. The Capo pull-out test has limited interest for surface preparation, as it is applicable to flat surfaces only. Conversely, the accelerated pull-out test showed interesting potential as a simple and relatively rapid means for assessing the mechanical integrity of a concrete surface prior to repair for any type of concrete surface. It appears from the results generated in this study that the combination Schmidt hammer / pull-off test could fill the needs for the evaluation of horizontal surfaces after concrete removal, while the combination Schmidt hammer / accelerated pull-out test could be used effectively on vertical and overhead surfaces. [less ▲]

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See detailInformatiser le Französisches Etymologisches Wörterbuch: la nécessaire prise en compte de l'utilisateur
Renders, Pascale ULg; Baiwir, Esther ULg

in Abel, Andrea; Vettori, Chiara; Ralli, Natascia (Eds.) Proceedings of the XVI EURALEX International Congress: The User in Focus, 15-19 juillet 2014 (2014)

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See detailPerturbation methods for the determination of the statistical response of nonlinear Volterra systems
Denoël, Vincent ULg; Carassale, Luigi

in Proceedings of the Eurodyn 2014 Conference (2014)

The point-like quasi-steady aerodynamic loading in a turbulent flow is formally expressed as a function of the squared relative velocity between the fluid and the investigated structure. The three major ... [more ▼]

The point-like quasi-steady aerodynamic loading in a turbulent flow is formally expressed as a function of the squared relative velocity between the fluid and the investigated structure. The three major terms governing the low-order statistics of the response are known to be related to the average loading, the linear turbulent loading and the aerodynamic damping. The three other terms in the loading, namely the quadratic turbulence term, the parametric velocity feedback term and the squared velocity term, may significantly affect the higher order statistical cumulants of the response. These latter two sources of fluid-structure interaction are usually disregarded, by lack of efficient simulation tools, except a Monte Carlo simulation of the nonlinear equation. In this paper, we provide a formal analysis of the complete nonlinear model, including thus all six terms, but mainly focusing on the importance of the two nonlinear coupling terms of the loading. Closed form solutions of the response are derived for a second-order Volterra model of this problem, under the assumption of different timescales in the loading and in the structural behavior. Two major outcomes of the analysis are, on the one hand, that the squared structural velocity term has no influence on the cumulants of the response up to order 4 and, on the other hand, that the parametric velocity feedback acts as a reduction of the non Gaussianity of the response. [less ▲]

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See detailApprentissage par renforcement batch fondé sur la reconstruction de trajectoires artificielles
Fonteneau, Raphaël ULg; Murphy, Susan A.; Wehenkel, Louis ULg et al

in Proceedings of the 9èmes Journées Francophones de Planification, Décision et Apprentissage (JFPDA 2014) (2014)

Cet article se situe dans le cadre de l’apprentissage par renforcement en mode batch, dont le problème central est d’apprendre, à partir d’un ensemble de trajectoires, une politique de décision optimisant ... [more ▼]

Cet article se situe dans le cadre de l’apprentissage par renforcement en mode batch, dont le problème central est d’apprendre, à partir d’un ensemble de trajectoires, une politique de décision optimisant un critère donné. On considère plus spécifiquement les problèmes pour lesquels l’espace d’état est continu, problèmes pour lesquels les schémas de résolution classiques se fondent sur l’utilisation d’approxima- teurs de fonctions. Cet article propose une alternative fondée sur la reconstruction de “trajectoires arti- ficielles” permettant d’aborder sous un angle nouveau les problèmes classiques de l’apprentissage par renforcement batch. [less ▲]

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See detailExperimental Study of the Human Ability to Deliberately Excite a Flexible Floor
Schwartz, Cédric ULg; Berger, Alexis; Bruls, Olivier ULg et al

in Zingoni, Alphose (Ed.) Proceedings of the 5th International Conference on Structural Engineering, Mechanics and Computation (2014)

Human-structure interactions are not completely understood yet. This paper presents an experimental study focusing on the interaction between a human and a flexible support, with a major aim to better ... [more ▼]

Human-structure interactions are not completely understood yet. This paper presents an experimental study focusing on the interaction between a human and a flexible support, with a major aim to better understand how the behavior of a human subject, bouncing on a flexible structure, adapts to the support motion. Exploratory experiments are undertaken with a 7m-span timber footbridge tested in the Human Motion Analysis Laboratory of the University of Liege. The movements of the coupled system composed of the subject and the footbridge are recorded by Motion Capture technology; the subject\textquoteright{}s 3-D body motion is defined by three important angles: ankle, knee and hip. The interaction between the subject and the footbridge is also quantified by means of force platform measurements. The experiments indicate an influence of the support amplitude and natural frequency on the phase shift between the oscillatory floor motion and the three angles characterizing the motion. [less ▲]

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See detailEnergetical aspects of solar-like oscillations in red giants
Grosjean, Mathieu ULg; Dupret, Marc-Antoine ULg; Belkacem, Kevin et al

in Precision Asteroseismology, Proceedings of the International Astronomical Union, IAU Symposium, Volume 301 (2014)

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See detailLes apports des travaux de la consultation du PUCA et les pistes de recherche
Merenne-Schoumaker, Bernadette ULg

in Lemercier, Evelyne (Ed.) Localisation des activités économiques et développement durable des territoires (2014)

Highlighting the results of the work that we have accompanied for three years by focusing on two questions of the research program: the location of economic activity it induces a local sustainable ... [more ▼]

Highlighting the results of the work that we have accompanied for three years by focusing on two questions of the research program: the location of economic activity it induces a local sustainable development and how the consideration of sustainable development changes does the issue of the location of these activities? Opening new avenues for further work [less ▲]

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See detailLes copies de la "Cène" de Léonard de Vinci
Fagnart, Laure ULg

in Mounier, Pascal; Nativel, Colette (Eds.) Copier et contrefaire à la Renaissance. Faux et usage de faux. Actes du colloque organisé par R.H.R. et la S.F.D.E.S. (2014)

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See detailDe l'alimentation à la médecine : l'utilisation du vin dans les papyrus littéraires grecs et latins relatifs à la cuisine et à la médecine
Marganne, Marie-Hélène ULg

in de Haro Sanchez, Magali; Boudon-Millot, Véronique (Eds.) « Des grains et du vin dans l’Antiquité : entre aliments et médicaments ». Journée d’étude organisée le 17 mai 2013 à Paris, Maison de la Recherche (2014)

Unlike the Egyptians who produced and consumed wine and beer from the earliest times, the Greeks and Romans are known mainly as producers and drinkers of wine. This paper attempts to address the question ... [more ▼]

Unlike the Egyptians who produced and consumed wine and beer from the earliest times, the Greeks and Romans are known mainly as producers and drinkers of wine. This paper attempts to address the question of the use of wine in cooking and medical recipes on Greek and Latin literary papyri from Egypt (IV/III BC – VI/VII AD). Do these texts manifest a local influence through mentions of Egyptian wine or beer or do they refer only to Greek (after the conquest of Alexander the Great in 332 BC) and Italian (after the annexation to the Roman state in 30 BC) wines? Furthermore, this study lists the properties and functions ascribed to wine(s) in these writings. [less ▲]

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See detailExpansion urbaine et risques hydrologiques : cas de Butembo (RD Congo)
Sahani, Muhindo; Ozer, Pierre ULg; Moeyersons, Jan

in Ozer, André; Ozer, Pierre (Eds.) Colloque International "La Géographie Physique et les Risques Naturels" - Livre de résumés (2014)

Butembo constitue un cas typique de zone urbaine en région tropicale humide rencontrant une explosion démographique exceptionnelle. L’exode vers Butembo pour fuir l’insécurité dans la sous-région a ... [more ▼]

Butembo constitue un cas typique de zone urbaine en région tropicale humide rencontrant une explosion démographique exceptionnelle. L’exode vers Butembo pour fuir l’insécurité dans la sous-région a conduit à une rapide concentration spontanée des populations et à une urbanisation sans cesse croissante. L’imperméabilisation des vastes étendues de terres consécutive à cette expansion spatiale rapide de la ville a généré des problèmes environnementaux qui affectent la structure urbaine. La ville est actuellement confrontée à des risques hydrologiques diversifiés : ravinements progressifs et régressifs, inondations, et remobilisation d’anciens glissements de terrain. [less ▲]

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See detailIntroduction. Guerre et jeu : vers les cultures d'un paradoxe à l'ère moderne
Küpper, Achim ULg

in Küpper, Achim; Vanden Berghe, Kristine (Eds.) Guerre et jeu. Cultures d'un paradoxe à l'ère moderne (2014)

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See detailLe financement rural du Niger : élément clé du développement
Andres, Ludovic ULg; Lebailly, Philippe ULg

in Brot, Jean (Ed.) Les Cahiers de l'Association Tiers-Monde n° 29-2014 : XXIXes Journées sur le Développement "Economie informelle et développement : emploi, financement et régulations dans un contexte de crise" (2014)

Ce document décrit les possibilités de financement du milieu rural (collectivités et ménages). L'analyse de l'offre a établi une typologie des financements en fonction des acteurs (public, privé formel et ... [more ▼]

Ce document décrit les possibilités de financement du milieu rural (collectivités et ménages). L'analyse de l'offre a établi une typologie des financements en fonction des acteurs (public, privé formel et informel). Elle discerne l'ensemble des possibilités de financement des ménages ruraux. La présente étude a été établie à partir d'interviews avec les acteurs clés du secteur, d'observations lors de mission sur le terrain et de données secondaires provenant de la BCEAO, des acteurs publics en matière de développement rural ainsi que d'une revue de littérature sur le financement rural, les Systèmes Financiers Décentralisés et la microfinance en Afrique de l'Ouest. [less ▲]

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See detailDu texte littéraire au document : les connexions entre les papyrus littéraires et documentaires grecs et latins
Marganne, Marie-Hélène ULg

in Derda, Tomasz; Urbanik, Jakub (Eds.) Actes du XXVIIe Congrès International de papyrologie (Varsovie, 29.07-03.08.2013) (2014)

Si l'on distingue généralement les papyrus littéraires et les papyrus documentaires grecs et latins, ces deux catégories présentent cependant, à côté du support, de l'écriture et des scribes, d'autres ... [more ▼]

Si l'on distingue généralement les papyrus littéraires et les papyrus documentaires grecs et latins, ces deux catégories présentent cependant, à côté du support, de l'écriture et des scribes, d'autres caractéristiques communes : certains papyrus paralittéraires présentent des traits documentaires ; d'autres papyrus sont trop fragmentaires pour être sûrement identifiés, soit comme littéraires, soit comme documentaires ; certains écrits comme les lettres et les discours peuvent, soit être liés à une profession ou à une circonstance particulière (documents), soit être fictifs (littéraires) ; des papyrus documentaires contiennent des citations ou des réminiscences littéraires ; des papyrus littéraires présentent un document sur l'autre face ; des papyrus littéraires font partie d'archives documentaires . Appliquant aux textes documentaires ou indéterminés la même grille d'analyse qu'aux textes littéraires, la nouvelle base de données du CEDOPAL permet de rendre compte de ces connexions et de les exploiter en vue de mieux évaluer les écrits concernés, les méthodes scribales mises en œuvre, ainsi que leur contexte de production et d'utilisation. [less ▲]

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See detailSaisir l’évaluation de l’université en actes : interprétations et appropriations des parties prenantes.
Charlier, Nathan ULg; Vangeebergen, Thomas ULg

in Fallon, Catherine; Leclercq, Bruno (Eds.) Leurres de la qualité dans l’enseignement supérieur. Variations internationales sur un thème ambigu (2014)

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See detailLes pseudo-déonomastiques arabes en français : Étude de cas et tentative de typologie
Baiwir, Esther ULg; Steffens, Marie ULg

in Dworkin, Steven; García arias, Xosé Lluis; Kramer, Johannes (Eds.) Actes du XXVIIe Congrès international de linguistique et de philologie romanes (Nancy, 15-20 juillet 2013). Section 6 : Étymologie (2014)

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See detailLes dieux et la cité. Représentations des divinités tutélaires entre Grèce et Phénicie
Bonnet, Corinne; Pirenne-Delforge, Vinciane ULg

in Zenzen, Nicolas; Hölscher, Tonio; Trampedach, Kai (Eds.) Aneignung und Abgrenzung. Wechselnde Perspektiven auf die Antithese von ‘Ost’ und ‘West’ in der griechischen Antike (2014)

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See detailClimate-proofing of large reservoirs in Belgium by the development of enhanced operation rules
Bruwier, Martin ULg; Dewals, Benjamin ULg; Erpicum, Sébastien ULg et al

in 3rd IAHR Europe Congress (2014)

Available climate change scenarios project drier summers and more humid winters for Belgium. This study addresses the impacts of those changes on the management of two multi-purpose reservoirs located in ... [more ▼]

Available climate change scenarios project drier summers and more humid winters for Belgium. This study addresses the impacts of those changes on the management of two multi-purpose reservoirs located in the Vesdre basin, and the search of enhanced operation rules to mitigate those changes. For this purpose, an integrated model is used, including a hydrological model of the Vesdre watershed, a hydraulic model of this river, a model of the dam complex operation rules and a flood risk model. Performance indicators of the dams are defined, representing drinking water production, damages due to floods, hydropower production and low-flow enrichment. First, a sensitivity analysis of the main parameters of the dam operation rules on the performance indicators is achieved. Afterwards, for two extreme climate scenarios at the time horizons 2021-2050 and 2071-2100, impacts of climate change on the reservoir performances are determined. Then, the results of the sensitivity analysis are used to indicate if climate change impacts may be mitigated by means of enhanced operation rules. [less ▲]

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See detailRobust optimal rendezvous using differential drag
Dell'Elce, Lamberto ULg; Martinusi, Vladimir ULg; Kerschen, Gaëtan ULg

in Proceedings of the AIAA/AAS Astrodynamics Specialist Conference (2014)

The practical realization of the differential drag technique for orbital relative maneuvers must cope with the several and severe uncertainty sources affecting drag modeling. Neglecting these ... [more ▼]

The practical realization of the differential drag technique for orbital relative maneuvers must cope with the several and severe uncertainty sources affecting drag modeling. Neglecting these uncertainties might yield to oversimplified solutions whose representation of a real-life scenario is questionable. The first outcome of this study consists in the synthesis of a robust optimal controller which combines differential flatness theory and the scenario approach to generate a reference path which can be easily followed. The second outcome is the characterization of the relevant uncertainties of the differential drag problem, with a special focus on the aerodynamic force. The developments are validated in a highly detailed simulation environment including, among the perturbations, advanced drag modeling and coupled attitude and orbital dynamics. [less ▲]

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See detailAssessing the quality of Experimental Data with Gaussian Processes: Example with an Injection Scroll Compressor
Quoilin, Sylvain ULg; Schrouff, Jessica ULg

in Proceedings of the 2014 Purdue Conferences (2014)

This paper describes an experimental study carried out on a refrigeration scroll compressor with and without vapour injection. The test rig designed for that purposed allows evaluating the performance ... [more ▼]

This paper describes an experimental study carried out on a refrigeration scroll compressor with and without vapour injection. The test rig designed for that purposed allows evaluating the performance over a wide range of operating conditions, by varying the supply pressure, the injection pressure, the discharge pressure, the supply superheating and the injection superheating. 97 Steady-state points are measured, with a maximum isentropic efficiency of 64.1% and a maximum consumed electrical power of 13.1 kW. A critical analysis of the experimental results is then carried out to evaluate the quality of the data using a machine learning method. This method based on Gaussian Processes regression, is used to build a statistical operating map of the compressor as a function of the different inputs. This statistical operating map can then be compared to the experimental data points to evaluate their accuracy. [less ▲]

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See detailFace à la globalisation : de l’interculturalité implicite à l’interculturalité engagée
Defays, Jean-Marc ULg

in EID, Cynthia; FADEL, Fady (Eds.) Interculturalité : Etat des lieux et perspectives, théories et pratiques (2014)

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See detailMathematical formulations of shallow water models with porosity for urban flood modeling
Bruwier, Martin ULg; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in ICHE 2014 : 11th International Conference on Hydroscience & Engineering (2014)

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See detailEnseignant de langues : de l’homme-orchestre au chef d’orchestre. Etat des lieux d’une discipline et d’une profession en questionnement
Defays, Jean-Marc ULg

in Maurer, Marie-Thérèse (Ed.) « L’enseignant au sein du dispositif d’enseignement/ apprentissage de la langue étrangère », Actes du Ve de l’Association des Directeurs de Centres Universitaires d’Etudes Françaises pour Etrangers (ADCUEFE), Université de Bourgogne, Dijon, 27-28 mai 2011 (2014)

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See detailArbitrage et ordre public européen
Caprasse, Olivier ULg

in Loquin, E.; Manciaux, S. (Eds.) L'ordre public et l'arbitrage (2014)

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See detailMeandering jets in shallow rectangular reservoir
Peltier, Yann ULg; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in 7th International Conference in River Hydraulics, River Flow 2014 (2014)

In this article, meandering flows in a shallow rectangular reservoir are experimentally and numerically investigated. Two experiments were performed in a smooth shallow horizontal flume and the surface ... [more ▼]

In this article, meandering flows in a shallow rectangular reservoir are experimentally and numerically investigated. Two experiments were performed in a smooth shallow horizontal flume and the surface velocity fields were measured by Large-Scale PIV (LSPIV). The flow conditions were chosen in such a way that the friction regime of both flows was different. These flows were then modelled using the academic code WOLF2D, which solves the 2D shallow water equations and uses a depth-averaged k- model for modelling turbulence. The main characteristics of the measured and simulated flows were finally extracted from a Proper Orthogonal Decomposition (POD) of the surface velocity fields and depth-averaged velocity fields respectively and were compared. When the mean fluctuating kinetic energy of the considered POD mode is greater than 1×10-5 m²/s², the numerical modelling and the experiments are in good agreement whatever the friction regime of the flow. [less ▲]

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See detailAvailable technical flexibility for balancing variable renewable energy sources: case study in Belgium
Quoilin, Sylvain ULg; Gonzalez Vazquez, Ignacio; Zucker, Andreas et al

in Proceedings of the 9th Conference on Sustainable Development of Energy, Water and Environment Systems (2014)

The recent evolution in power systems, including increased share of renewables and a modification of the power plant fleets entail new constraints, e.g. on the peak capacity or on the technical ... [more ▼]

The recent evolution in power systems, including increased share of renewables and a modification of the power plant fleets entail new constraints, e.g. on the peak capacity or on the technical flexibility required on the grid. This study simulates the Belgian power system using Dispa-SET, a unit commitment and optimal dispatch model developed within the Joint Research Centre. Different “what-if” scenarios are defined and evaluated by varying the availability of major nuclear and CCGT power plants, or the share of renewable capacity in the system. Key findings include: If the nuclear power plants of Doel 1, 2 and 4 had not been available in 2012-2013, 76 hours of capacity deficit would have been stated. If, in addition, the two CCGT power plants of Vilvoorde and Seraing had been disconnected, the number of deficit hours would have risen to 450. There is enough technical flexibility on the system to accommodate significant shares of renewable energy (up to 8 GW additional capacity, corresponding to 17% of the yearly generation). CCGT power plants are submitted to more on/off cycles as the share of renewable energy increases. In high renewable penetration scenarios, CCGT power plant are committed preferably over less flexible nuclear or coal power plants. It is therefore necessary to set up proper markets mechanisms to maintain these plants on the grid. [less ▲]

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See detailDetection of near-field, low permittivity layers with Ground Penetrating Radar: analytical estimation of the reflection coefficient
Van der Wielen, Audrey; Courard, Luc ULg; Nguyen, Frédéric ULg

in LAMBOT, Sébastien (Ed.) Proceedings of 15th International Conference on ground Penetrating Radar (2014)

The reflection coefficient of GPR waves encountering embedded thin layers is commonly estimated using a plane wave, far field approximation. But when the thin layer is situated in the near field of the ... [more ▼]

The reflection coefficient of GPR waves encountering embedded thin layers is commonly estimated using a plane wave, far field approximation. But when the thin layer is situated in the near field of the antenna, the spherical nature of the waves and the possible propagation of a lateral wave into the layer may have a strong influence on the measured reflected amplitude. In this work, we studied through 2D FDTD simulations the behavior of a radar wave interacting with thin layers of different thicknesses. The snapshots and radargrams showed a large influence of the layer thickness on the wave propagation. For the very thin layers, the evanescent wave plays a major role and the plane wave approximation gives a good estimation of the reflection coefficient. For thicker layers, the specific inclination of each multiple reflection has to be taken into account, as well as the lateral wave propagation. On the basis of these observations, we determined which analytical method should be used for the analytical prediction of the reflection coefficient, as a function of the layer thickness. [less ▲]

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See detailMultiscale aspects in modeling percussive drilling: from wave propagation to rigid body dynamics
Depouhon, Alexandre ULg; Denoël, Vincent ULg; Detournay, Emmanuel

in Proceedings of the 3rd International Colloquium on Nonlinear Dynamics and Control of Deep Drilling Systems (2014)

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See detailDesigning and testing an air-PCM heat exchanger for building ventilation application coupled to energy storage
Dechesne, Bertrand ULg; Gendebien, Samuel ULg; Martens, Jonathan et al

in 2014 Purdue Conferences Proceedings (2014)

This paper studies a PCM heat exchanger coupled to a building ventilation system. This PCM module can either store heat during the day (e.g. by cooling solar PV panels) and restore it to the building ... [more ▼]

This paper studies a PCM heat exchanger coupled to a building ventilation system. This PCM module can either store heat during the day (e.g. by cooling solar PV panels) and restore it to the building during the night for space heating purposes or store coolness during the night and give it back during the day and thus act as a free cooling system. This project aims to develop a performing air-PCM heat exchanger providing latent energy storage of 0.5 kWh, this energy is delivered between 15 and 30°C. This heat exchanger is based on corrugated cells that can be easily filled, lined up and then locked in a box, letting the air pass between the cells. The PCM used for the prototype is c omposed of fatty acids. In order to develop an efficient PCM ventilation module, two different ways of investigation were followed and used in parallel. The first one used CFD simulations and the second one, a semi-empirical model based on correlations. The CFD simulations were able to predict the convection coefficient on the air side and also show the flow repartition between the different channels whereas the semi-empirical model allowed a parametrical study in order to identify the best geometry possible. Once the heat exchanger geometry was optimized, a test bench was built and a prototype of air-PCM heat exchanger was manufactured in order to measure its thermal and hydraulic performances. The tests consist in either a complete solidification or liquefaction of the PCM starting from respectively liquid PCM at 30°C or solid PCM at 15°C. The airflow rate was set to 45m³/h, which corresponds barely to the ventilation rate of a traditional room in a residential building. A comparison between the models and the measurements was carried out in order to calibrate the semi-empirical model. It will be shown that a simple semi-empirical model satisfactorily predicts the evolution of heat transfer rate for different operating conditions. [less ▲]

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See detailEfficient estimation of the high-order response statistics of a wind-excited oscillator with nonlinear velocity feedback
Denoël, Vincent ULg; Carassale, Luigi

in Proceedings of the XIII Conference of the Italian Association for Wind engineering (2014)

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See detailAdhérence des réparations en béton: évaluation et facteurs d'influence
Bissonnette, Benoït; Courard, Luc ULg; Jolin, Marc et al

in Damidot, Denis (Ed.) Actes de la 15ème édition des journées scientifiques (2014)

La réparation et le renforcement des structures existantes en béton comptent parmi les plus importants défis auxquels les ingénieurs civils sont confrontés aujourd’hui et qu’ils devront relever dans les ... [more ▼]

La réparation et le renforcement des structures existantes en béton comptent parmi les plus importants défis auxquels les ingénieurs civils sont confrontés aujourd’hui et qu’ils devront relever dans les années à venir. Les préoccupations actuelles concernant le développement durable favorisent la réfection au détriment de la construction neuve et ne peuvent que renforcer cette tendance. Des efforts concertés de la part des scientifiques et ingénieurs sont encore nécessaires afin d’améliorer la conception des réparations en béton et d’en assurer la qualité et la fiabilité attendues. L’un des aspects essentiels de la durabilité des réparations en béton et des revêtements ou traitements de surface est la qualité de l’adhérence entre le matériau de réparation et le béton existant. Le présent article résume les principales conclusions de travaux réalisés en collaboration en vue d’identifier les facteurs influençant l’adhérence des réparations (la rugosité, le degré de saturation et la carbonatation du substrat) et l’évaluation de celle-ci en conditions in situ (type de chargement, alignement de l’appareil). Sur la base des résultats recueillis, des recommandations concernant la préparation de la surface avant réparation ont été émises dans un guide du USBR aux États-Unis. [less ▲]

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See detailLes TICE dans les approches interculturelles en classe de FLE/S : Leviers ou obstacles dans l’apprentissage de l’écrit ? Pratiques déclarées et représentations d’enseignants de FLE/S en contexte universitaire
Dezutter, Olivier; Bleys, Françoise; Eid, Rodine et al

in EID, Cynthia; FADEL, Fady (Eds.) Les interculturalités, État des lieux et perspectives, théories et pratiques (2014)

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See detailNanocomposite fiber reinforced mortars
Coppola, Bartolomeo; Di Maio, Luciano; Courard, Luc ULg et al

in Proceedings of the International Conference on Composites/Nano Engineering (2014)

The use of fibers to reinforce a brittle material is an extensively studied application. In the field of cementitious materials a wide range of fibers have been investigated, from natural to synthetic ... [more ▼]

The use of fibers to reinforce a brittle material is an extensively studied application. In the field of cementitious materials a wide range of fibers have been investigated, from natural to synthetic fiber (wood, cellulose, carbon, glass, polypropylene) in order to achieve several purposes. Nowadays there is a continuing effort to take advantage of recent advances in nanotechnology, in the polymer and fiber industry. Nanoclays are some of the most affordable materials that have shown promising results in nanocomposite polymers. They are characterized by a “platelet” structure with average dimension of 1 nm thick and 70 to 150 nm wide. This work is aimed at studying the different behavior of fiber reinforced mortars, containing nanocomposite polymeric fibers. [less ▲]

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See detailLearning dextrous grasps that generalise to novel objects by combining hand and contact models
Kopicki, Marek; Detry, Renaud ULg; Schmidt, Florian et al

in IEEE International Conference on Robotics and Automation (2014)

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See detailImages de guerre dans quelques passions donatistes africaines
Fialon, Sabine ULg

in Coltellonoi-Trannoy; Le Bohec, Yann (Eds.) La guerre dans l'Afrique romaine sous le Haut-Empire (2014)

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See detailTerqa Ceramic Culture during the 3rd Millennium BC. Material from 18th-26th Excavation Campaigns
Mas, Juliette ULg

in Bieliński, P.; et al. (Eds.) Proceedings of the 8th International Congress on the Archaeology of the Ancient Near East, 30 April – 4 May 2012, University of Warsaw, Volume 2: Excavation and Progress Reports, Posters (2014)

Terqa, an important Syrian Bronze Age site located in the Lower Middle-Euphrates region, benefited from a key position which provided the settlement with the opportunity to gain from exchanges and ... [more ▼]

Terqa, an important Syrian Bronze Age site located in the Lower Middle-Euphrates region, benefited from a key position which provided the settlement with the opportunity to gain from exchanges and innovations arriving from both the North and South, while developing its own identity and culture. A new study on pottery has just been carried out on 3rd-millennium material from eight excavation seasons. The recovered material has been used to specify Terqa’s chronostratigraphy with greater accuracy, comparing it with the neighboring site of Mari and other contemporary ones but also providing us with a preliminary overview of Terqa’s ceramic culture during the Early Bronze Age. [less ▲]

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See detailLe patron urbain, un facteur influençant l'impact de l'urbanisation sur les écosystèmes: les cas de Kisangani et de Lubumbashi (RDC)
Andre, Marie ULg; Mahy, Grégory ULg; Lejeune, Philippe ULg et al

in PACODEL (Ed.) Colloque international Territoires périurbains: développement, enjeux et perspectives dans les pays du sud (2013, December 19)

Les dynamiques et patrons paysagers de deux villes entre deux années (Kisangani entre 2002 et 2010 ; Lubumbashi entre 2002 et 2008, en République Démocratique du Congo) ont été étudiés afin d’évaluer leur ... [more ▼]

Les dynamiques et patrons paysagers de deux villes entre deux années (Kisangani entre 2002 et 2010 ; Lubumbashi entre 2002 et 2008, en République Démocratique du Congo) ont été étudiés afin d’évaluer leur influence sur l’impact de l’extension et/ou densification de ces villes, et plus particulièrement de leur zone périurbaine, sur leurs écosystèmes internes et périphériques. En effet, le patron paysager occupe une place fondamentale dans l’hypothèse centrale de l’écologie du paysage, appelée pattern-process paradigm puisqu’il influence les processus écologiques et inversement. Sa description et son analyse sont donc particulièrement importantes (Bogaert et al. 2004; Coulson et al. 1999). Les indices de composition, communément utilisés en écologie du paysage, décrivent entre autres le patron en quantifiant la présence et le nombre de taches issues des différentes classes du paysage (Alberti 2008). D’autre part, les villes ne cessant d'augmenter leur emprise sur les paysages dont elles font partie, l'étude des espaces qui les ceinturent, le phénomène de leur extension dans les régions rurales ainsi que les schémas conceptuels de leur morphologie et dynamique interne sont plus que jamais des sujets d'actualité (Bhatta et al., 2010; Borsdorf et al., 2002; De Blij, 1977; Gaston, 2010; Halleux, 2006). Paradoxalement, les scientifiques de différentes disciplines peinent à donner une définition, des caractéristiques et des limites acceptées par tous aux notions se rattachant aux différentes zones présentes dans le gradient urbain-rural. Cette étude se distingue des autres, généralement subjectives, par son approche quantifiée et objective. Pour chacune des deux villes, deux images SPOT 5 ont été classifiées sur base d’une approche orientée-objet (Definiens 2013). Ensuite, des indices de composition paysagère ont été évalués afin 1) d’identifier l’étendue de chaque zone (urbaine, périurbaine, rurale) au sein du gradient urbain-rural en utilisant les définitions de zones proposées par André et al. (sous presse), 2) de décrire ces différentes zones en quantifiant les caractéristiques morphologiques les plus couramment citées avant d’en borner les valeurs (André et al. 2012) et 3) de quantifier la dynamique des différentes zones au cours de la dernière décade. Ensuite, les similarités et différences entre ces villes ainsi que la pertinence et les faiblesses de la méthode ont été identifiées et discutées. Les résultats de cette étude ont pour ambition de contribuer à une meilleure compréhension et prise en compte du rôle du patron paysager dans la résistance potentielle des écosystèmes naturels à l’extension et/ou la densification d’une ville donnée. [less ▲]

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See detailEncres anciennes: utilisation non conventionnelle d'aliments
Bouchat, Isabelle; Wymeersch, Noémie; Bchir, Brahim ULg et al

in Septième symposium du GCNAS: Vendredi 6 décembre, Louvain-La-Neuve (2013, December 06)

De tout temps l’homme utilise des pigments pour peindre. Il y a 27.000 ans déjà, près de Marseille, dans la grotte Cosquer, des fresques furent peintes par des hommes préhistoriques. Il existe deux ... [more ▼]

De tout temps l’homme utilise des pigments pour peindre. Il y a 27.000 ans déjà, près de Marseille, dans la grotte Cosquer, des fresques furent peintes par des hommes préhistoriques. Il existe deux grandes catégories de pigments et colorants: les naturels et les artificiels. La première catégories contient les pigments minéraux tels que les argiles (ocre jaune ou rouge, argile verte ou brune) mais aussi des pierres (lapis lazuli (bleu)) et les pigments organiques d’origine végétale (gaude (jaune)) ou d’origine animale (murex (pourpre). La deuxième catégorie contient les pigments et colorants artificiels issus de réactions chimiques (minium (orange)) ou bien des mi-végétaux, mi-minéraux comme les encres ferro-galliques classés dans les divers. Après avoir servi pendant plusieurs siècles, tous ces pigments ont été remplacés à la fin du XIXe par des colorants synthétiques issus de la pétrochimie, car ces derniers ont l'avantage de la reproductibilité constante des couleurs. Mais la fin programmée du pétrole suscite un regain d'intérêt pour les préparations naturelles. C'est donc très logiquement que notre laboratoire a décidé de s'intéresser au sujet et en particulier aux encres venant du jus de chou rouge et aux encres ferro-grenadiques en collaboration avec l'Abbaye de Villers-la-Ville. [less ▲]

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See detailEvaluation de la Teneur Sanguine en Sélénium dans le Sang des Vaches en Wallonie (Belgique)
Mehdi, Youcef ULg; Cabaraux, Jean-François ULg; Hornick, Jean-Luc ULg et al

in 20ième Rencontre Recherches Ruminants (2013, December 04)

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See detailObservations of Red Giants in the Cluster NGC 6633 by the CoRoT Space Mission and the HARPS and SOPHIE Spectrometers
Barban, C.; Baudin, F.; Poretti, E. et al

in Astronomical Society of the Pacific Conference Series (2013, December 01)

The CoRoT space mission and the HARPS and SOPHIE ground-based spectrometers have observed red giants belonging to the open cluster NGC 6633. Solar-like oscillations are detected in the CoRoT data obtained ... [more ▼]

The CoRoT space mission and the HARPS and SOPHIE ground-based spectrometers have observed red giants belonging to the open cluster NGC 6633. Solar-like oscillations are detected in the CoRoT data obtained for four red giants. Spectroscopic data questions the cluster membership of one of these stars. The combination of these photometric and spectroscopic data will be a unique opportunity to estimate their global parameters as well as to probe their internal structure. [less ▲]

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See detailNon-Perturbative Effect of Rotation on Dipolar Mixed-Modes in Red Giants
Ouazzani, R.-M.; Goupil, M.-J.; Dupret, Marc-Antoine ULg et al

in Astronomical Society of the Pacific Conference Series (2013, December 01)

The space missions CoRoT (Convection Rotation and Planetary Transits) and Kepler provide high quality data that allows the transport of angular momentum in stars to be investigated by the seismic ... [more ▼]

The space missions CoRoT (Convection Rotation and Planetary Transits) and Kepler provide high quality data that allows the transport of angular momentum in stars to be investigated by the seismic determination of the internal rotation profile. In a former study (Ouazzani et al. 2013b) we test the validity of seismic diagnostics for red giant rotation that are based on a perturbative method. Our aim here is to investigate oscillation spectra when that validity no longer holds. We use a non-perturbative approach implemented in the Adiabatic Code of Oscillations including Rotation (ACOR code) (Ouazzani et al. 2012) that accounts for the eff [less ▲]

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See detailBrèves considérations sur le budget général des dépenses de l'autorité fédérale
Behrendt, Christian ULg

in Uyttendaele, Marc; Sautois, Joëlle (Eds.) La sixième réforme de l'Etat (2012-2013) : Tournant historique ou soubresaut ordinaire ? (2013, December 01)

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See detailDifferential Seismic Modeling of Stars
Ozel, N.; Mosser, B.; Dupret, Marc-Antoine ULg et al

in Astronomical Society of the Pacific Conference Series (2013, December 01)

CoRoT (Convection Rotation and planetary Transits) observations provide the opportunity to study a large sample of stars ranging from the Main Sequence (MS) to the Red Giant Branch. With the large ... [more ▼]

CoRoT (Convection Rotation and planetary Transits) observations provide the opportunity to study a large sample of stars ranging from the Main Sequence (MS) to the Red Giant Branch. With the large increase in the number of stars showing solar-like oscillations, we intend to extract as much information as possible from a low signal-to-noise ratio (SNR) oscillation spectrum, benefiting from comparison with a reference star having similar seismic and fundamental parameters. We propose a differential method to determine stellar properties of solar-like oscillations which we call “differential seismology of stellar twins”. [less ▲]

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See detail"Le roi Louis, en admiration devant le repas du Christ à Milan". Les Français et la "Cène" de Léonard de Vinci
Fagnart, Laure ULg

in Elsig, Frédéric; Natale, Mauro (Eds.) Le duché de Milan et les commanditaires français (1499-1521) (2013, December)

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See detailStructural Modelling of the Annulus Fibrosus - an Anisotropic Hyperelastic Model Approach at the Lamellar Level
Mengoni, Marlène ULg; Wijayathunga, V. N.; Jones, Alison C. et al

in Nithiarasu, P.; Löhner, R. (Eds.) Proceedings of the 3rd International Conference on Computational Mathematical Biomedical Engineering (2013, December)

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See detailINFLUENCE OF SOLUBLE PROTEINS ON THE ADHERENCE OF PARTICULATE SOILS
Toure, Yetioman ULg; Rouxhet, Paul; Dupont-Gillain, Christine et al

in Malayeri, Reza; Watkinson, Paul A.; Müller-Steinhagen, Hans (Eds.) Proceedings of International Conference on Heat Exchanger Fouling and Cleaning - 2013 (Peer-reviewed) (2013, December)

Adsorbed compounds from food and pharmaceutical mixtures may influence interactions at interfaces and thus fouling and cleaning. In this study, quartz particles (10 to 30µm) were used as a model soil for ... [more ▼]

Adsorbed compounds from food and pharmaceutical mixtures may influence interactions at interfaces and thus fouling and cleaning. In this study, quartz particles (10 to 30µm) were used as a model soil for examining the effect of dissolved proteins on the cleanability of substrates after soiling and drying. Glass and stainless steel pretreated by UV-Ozone (StSteel-UVO) were used as model hydrophilic substrates, while hydrophobic substrates were represented by stainless steel cleaned with ethanol (StSteel-Eth) and polystyrene. BSA and β-LGB were used as proteins. The quartz suspensions used for soiling were prepared in pure water and in a solution of each protein. After soiling and drying, the cleanability was evaluated using a radial-flow cell, with pure water as the cleaning fluid. The presence of proteins in the suspension used for soiling hydrophilic substrates (Glass and StSteel-UVO), decreased the adherence of quartz particles. Its effect was less marked and tended to be opposite for less hydrophilic substrates (StSteel-Eth, Polystyrene). The adherence cannot be explained by a simple relation with the contact angle. Other factors may be the solution surface tension itself and the protein behavior at the interfaces created by drying and by rehydratation during cleaning. When considering the influence of substrate on soiling, it must be kept in mind that high surface energy solids (metals, oxides) are readily contaminated in contact with air and lose their hydrophilicity. This may improve the substrate behavior regarding cleanability with respect to particulate soil. [less ▲]

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See detailUnderstanding variable importances in forests of randomized trees
Louppe, Gilles ULg; Wehenkel, Louis ULg; Sutera, Antonio ULg et al

in Advances in Neural Information Processing Systems 26 (2013, December)

Despite growing interest and practical use in various scientific areas, variable importances derived from tree-based ensemble methods are not well understood from a theoretical point of view. In this work ... [more ▼]

Despite growing interest and practical use in various scientific areas, variable importances derived from tree-based ensemble methods are not well understood from a theoretical point of view. In this work we characterize the Mean Decrease Impurity (MDI) variable importances as measured by an ensemble of totally randomized trees in asymptotic sample and ensemble size conditions. We derive a three-level decomposition of the information jointly provided by all input variables about the output in terms of i) the MDI importance of each input variable, ii) the degree of interaction of a given input variable with the other input variables, iii) the different interaction terms of a given degree. We then show that this MDI importance of a variable is equal to zero if and only if the variable is irrelevant and that the MDI importance of a relevant variable is invariant with respect to the removal or the addition of irrelevant variables. We illustrate these properties on a simple example and discuss how they may change in the case of non-totally randomized trees such as Random Forests and Extra-Trees. [less ▲]

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See detailHypopituitarism in pituitary gigantism (results of an international study)
Rostomyan, Liliya ULg; Daly, Adrian ULg; Shah, NS et al

in The 3rd ENEA Workshop : Hypopituitarism - Abstract book (2013, December)

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See detailA giant treated with growth hormone
Rostomyan, Liliya ULg; Potorac, Iulia ULg; CASTERMANS, Emilie ULg et al

in The 3rd ENEA Workshop : Hypopituitarism - Abstract book (2013, December)

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See detailEvaluation de la composition des huiles d’olive de nouvelles variétés d’olivier introduites dans la région orientale du Maroc
Mansouri, Farid; Ben moumen, Abdessamad; Fauconnier, Marie-Laure ULg et al

in 6èmes Journées internationales d'étude sur les lipides - Programme scientifique, Recueil des Résumés (2013, December)

Le secteur oléicole marocain a connu une évolution importante au niveau des superficies qui ont atteint 900000 ha (*MAPM, 2011). La structure variétale du verger oléicole marocain est caractérisée par la ... [more ▼]

Le secteur oléicole marocain a connu une évolution importante au niveau des superficies qui ont atteint 900000 ha (*MAPM, 2011). La structure variétale du verger oléicole marocain est caractérisée par la prédominance de la Picholine marocaine, qui représente plus de 96 % du patrimoine national et qui est à double fin. [less ▲]

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See detailA management control perspective of sustainability reporting in higher education : in search of a holistic view
Ceulemans, Kim; Van Caillie, Didier ULg; Molderez, Isabelle et al

in Lehner, Othmar; Harrison (Eds.) Proceedings in Finance and Risk series '13 (2013, December)

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