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See detailCoMBiSpeC: A novel approach in the modelling of massive binaries
Palate, Matthieu ULg

in EAS Publications Series (2014, February 01)

Spectral modelling and especially for massive stars is not a straightforward problem and over the past decades many advances have been made in this field. We now have sophisticated model atmosphere codes ... [more ▼]

Spectral modelling and especially for massive stars is not a straightforward problem and over the past decades many advances have been made in this field. We now have sophisticated model atmosphere codes that allow to derive the stellar parameters. However, these codes are based on the assumption that the star is single and spherical which is no longer valid for the components of a binary system. On the other hand, observational studies indicate that binarity has an impact on the spectra. This is why we have developed a model called CoMBiSpeC (code of massive binary spectral computation) that specifically accounts for the impact of binarity on the spectra. [less ▲]

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See detailSpectroscopic survey of Kepler stars: high-resolution observations of A- and F-type stars
Niemczura, E.; Smalley, B.; Murphy, S. et al

in IAU Symposium (2014, February 01)

Basic stellar parameters such as effective temperature, surface gravity, chemical composition, and projected rotational velocity, are important to classify stars and are crucial for successful ... [more ▼]

Basic stellar parameters such as effective temperature, surface gravity, chemical composition, and projected rotational velocity, are important to classify stars and are crucial for successful asteroseismic modelling. However, the Kepler space data do not provide such information. Therefore, ground-based spectral and multi-colour observations of Kepler asteroseismic targets are necessary to complement the space data. For this purpose, in coordination with the KASC ground-based observational Working Groups, high-resolution spectroscopic data for more than 500 B, A, F and G-type stars were collected. [less ▲]

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See detail7. Lutte intégrée contre les ravageurs
Chavalle, Sandrine; Censier, Florence ULg; Jacquemin, Guillaume et al

in Destain, Jean-Pierre; Bodson, Bernard (Eds.) Livre Blanc Céréales (2014, February)

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See detailMetal Enhanced Fluorescence: effect of surface coating
Lismont, Marjorie ULg; François, Alexandre; Dreesen, Laurent ULg et al

in SPIE proceeding (2014, February)

Among the emerging treatments for cancer, Photodynamic Therapy (PDT) is thought to be one of the most promising. PDT uses light sensitive molecules, or photosensitizer, to produce, under specific ... [more ▼]

Among the emerging treatments for cancer, Photodynamic Therapy (PDT) is thought to be one of the most promising. PDT uses light sensitive molecules, or photosensitizer, to produce, under specific irradiation, toxic reactive oxygen species (ROS) to kill cancer cells. However, the amount of ROS generated is limited by both the fluorescence lifetime of the photosensitizer and its concentration around the cancer cells. Metal Enhanced Fluorescence (MEF), a phenomenon arising when a fluorophore is in closed proximity to a metallic structure such as metallic films or nanostructures, is seen as a way to solve these problems by reducing the fluorescence lifetime and increasing the fluorescence emission of the fluorophore. Protoporphyrin IX (PpIX) is a commonly used photosensitizer to treat skin cancers, which presents an intense absorption band around 400 nm while emitting around 630 nm. Because silver nanoparticles (Ag NPs) exhibit a strong Localized Surface Plasmon Resonance (LSPR) around 400 nm, MEF of the PpIX is expected when immobilized onto Ag NPs. Here, we investigate the relevant parameters influencing the coupling effects between the LSPR in Ag NPs and PpIX attached onto the Ag NPs surface when the Ag NPs are dispersed in solution or electrostatically bound to a glass slide. In particular, we study the distance-dependent of MEF by applying multiple layers of polyelectrolyte to progressively increase the distance between Ag NPs and PpIX, covalently bond to the last polyelectrolyte layer as well as exploring the use of Ag NPs of different sizes ranging from 40 to 100 nm. [less ▲]

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See detailBronchiectasis
Clercx, Cécile ULg

in Proceedings 35 Internationaler Fortbildungskurs Kleintierkrankheiten (2014, February)

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See detailCorrelations of the High Resolution MRI aspect of GH-secreting pituitary adenomas prior to treatment
Potorac, Iulia ULg; PETROSSIANS, Patrick ULg; Schillo, F et al

in Abstract book - Symposium "Perspectives in Endocrinology" Congresses Highlights 2013:ECE Copenhagen, ENDO SF, SFE Paris (2014, February)

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See detailLong fibrosis
Clercx, Cécile ULg

in proceedings 35 Internationaler Fortbildungskurs Kleintierkrankheiten (2014, February)

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

in Abstract book - Symposium "Perspectives in Endocrinology" Congresses Highlights 2013:ECE Copenhagen, ENDO SF, SFE Paris (2014, February)

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See detailNovel fibroblast growth factor receptor 1 mutation causing normosmic idiopathic hypogonadotropic hypogonadism
Chachati, AS; Potorac, I; DEBRAY, François-Guillaume ULg et al

in Abstract book - Symposium "Perspectives in Endocrinology" Congresses Highlights 2013:ECE Copenhagen, ENDO SF, SFE Paris (2014, February)

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See detailEvaluation of the Response of Shear Critical Walls Using a Three-Parameter Kinematic Theory
Mihaylov, Boyan ULg; Hannewald, Pia; Beyer, Katrin

in The 4th International fib Congress 2014 Mumbai - Proceedings (2014, February)

This paper discusses a newly developed three-parameter kinematic theory (3PKT) for shear critical walls with the help of four wall tests. The 3PKT is used to predict the pre- and post- peak response of ... [more ▼]

This paper discusses a newly developed three-parameter kinematic theory (3PKT) for shear critical walls with the help of four wall tests. The 3PKT is used to predict the pre- and post- peak response of the test units. Comparisons are performed with finite element (FE) models and plastic hinge models in combination with a shear degradation model. It is found that the latter underestimate the displacement capacity of the walls while the former do not predict well the post-peak response. The 3PKT with only three degrees of freedom captures the complete response of the walls provided that the size of the critical loading zone (CLZ) of the wall is well predicted. [less ▲]

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See detailEffective stress method to be used in beam finite elements to take local instabilities into account
Franssen, Jean-Marc ULg; Cowez, Baptiste; Gernay, Thomas ULg

in Proceedings of the 11th IAFSS Symposium (2014, February)

In the fire situation, Bernoulli beam finite elements are the workhorse used in numerical calculation model for simulating the behaviour of the structure. Such finite elements treat all sections as class ... [more ▼]

In the fire situation, Bernoulli beam finite elements are the workhorse used in numerical calculation model for simulating the behaviour of the structure. Such finite elements treat all sections as class 1 (stocky) sections whatever the slenderness of the plates that make the section, allowing the development of a full plastic stress distribution in the section which leads to complete plastic redistribution along the members in the structure. This type of element is thus not adapted for modeling structures that contain slender sections of class 2, 3 or 4. This document presents a new approach to take into account local instabilities in slender sections using beam finite elements. The new approach is based on an effective constitutive law of steel. The effective law is not symmetrical with respect to tension and compression because, in tension, the stress-strain relationship is not modified whereas, in compression, the stress-strain relationship is modified. [less ▲]

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See detailBacterial and viral pneumonia
Clercx, Cécile ULg

in Proceedings 35 Internationaler Fortbildungskurs Kleintierkrankheiten (2014, February)

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See detailDamage Detection in Civil Engineering Structure Considering Temperature Effect
Nguyen, Viet Ha; Mahowald, Jean; Maas, Stefan et al

in Proceedings of IMAC XXXII Dynamics of Coupled Structures (2014, February)

This paper concerns damage identification of a bridge located in Luxembourg. Vibration responses were captured from measurable and adjustable harmonic swept sine excitation and hammer impact. Different ... [more ▼]

This paper concerns damage identification of a bridge located in Luxembourg. Vibration responses were captured from measurable and adjustable harmonic swept sine excitation and hammer impact. Different analysis methods were applied to the data measured from the structure showing interesting results. However, some difficulties arise, especially due to environmental influences (temperature and soil-behaviour variations) which overlay the structural changes caused by damage. These environmental effects are investigated in detail in this work. First, the modal parameters are identified from the response data. In the next step, they are statistically collected and processed through Principal Component Analysis (PCA) and Kernel PCA. Damage indexes are based on outlier analysis. [less ▲]

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See detailSubspace and nonlinear-normal-modes-based identification of a beam with softening-hardening behaviour
Grappasonni, Chiara ULg; Noël, Jean-Philippe ULg; Kerschen, Gaëtan ULg

in Proceedings of the International Modal Analysis Conference (IMAC) XXXII (2014, February)

The capability to reproduce and predict with high accuracy the behaviour of a real system is a fundamental task of numerical models. In nonlinear structural dynamics, additional parameters compared to ... [more ▼]

The capability to reproduce and predict with high accuracy the behaviour of a real system is a fundamental task of numerical models. In nonlinear structural dynamics, additional parameters compared to classical linear modelling, which include the nonlinear coefficient and the mathematical form of the nonlinearity, need to be identified to bring the numerical predictions in good agreement with the experimental observations. In this context, the present paper presents a method for the identification of an experimental cantilever beam with a geometrically nonlinear thin beam clamped with a prestress, hence giving rise to a softening-hardening nonlinearity. A novel nonlinear subspace identification method formulated in the frequency domain is first exploited to estimate the nonlinear parameters of the real structure together with the underlying linear system directly from the experimental tests. Then a finite element model, built from the estimated parameters, is used to compute the backbone of the first nonlinear normal mode motion. These numerical evaluations are compared to a nonlinear normal modes-based identification of the structure using system responses to stepped sine excitation at different forcing levels. [less ▲]

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See detailInternal Resonance and Stall-Flutter in a pitch-Flap Wing in the Wind-Tunnel
Verstraelen, Edouard ULg; Kerschen, Gaëtan ULg; Dimitriadis, Grigorios ULg

in Proceedings of the SEM IMAC XXXII (2014, February)

Nonlinear aeroelastic phenomena such as store-induced LCOs, transonic buzz and stall flutter are the burden or modern aircraft: they reduce the performance and can even limit the flight envelope in both ... [more ▼]

Nonlinear aeroelastic phenomena such as store-induced LCOs, transonic buzz and stall flutter are the burden or modern aircraft: they reduce the performance and can even limit the flight envelope in both civil and military cases. Several nonlinear setups were studied experimentally in the last decades by the scientific community but most of them have pitch and plunge degrees of freedom and feature a rigid wing. In this paper, we study a new nonlinear aeroelastic apparatus that features nonlinear pitch and flap degrees of freedom, coupled with a flexible wing. The model is tested experimentally in the wind tunnel to determine its dynamic behaviour. Preliminary observations demonstrate that the system undergoes a supercritical Hopf bifurcation due to the hardening nonlinearity followed by an amplitude jump that is the consequence of either dynamic stall (i.e. stall flutter) or internal resonance (i.e. interaction between the hardening nonlinearity and higher modes). [less ▲]

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

in Abstract book - Symposium "Perspectives in Endocrinology" Congresses Highlights 2013:ECE Copenhagen, ENDO SF, SFE Paris (2014, February)

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See detailClinical characteristics of patients with AIP mutation-related prolactinomas
Camby, S; Daly, Adrian ULg; VROONEN, Laurent ULg et al

in Abstract book - Symposium "Perspectives in Endocrinology" Congresses Highlights 2013:ECE Copenhagen, ENDO SF, SFE Paris (2014, February)

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See detailLe PPNAD, une cause rare de syndrome de Cushing
Petignot, S; VROONEN, Laurent ULg; HAMOIR, Etienne ULg et al

in Abstract book - Symposium "Perspectives in Endocrinology" Congresses Highlights 2013:ECE Copenhagen, ENDO SF, SFE Paris (2014, February)

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See detailReceptor expression in craniopharyngiomas causing tumor growth in pregnancy : case report and review of the literature
VROONEN, Laurent ULg; Tome Garcia, M; THIRY, Albert ULg et al

in Abstract book - Symposium "Perspectives in Endocrinology" Congresses Highlights 2013:ECE Copenhagen, ENDO SF, SFE Paris (2014, February)

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See detailChronische Bronchitis Hund
Clercx, Cécile ULg

in Proceedings 35 Internationaler Fortbildungskurs Kleintierkrankheiten (2014, February)

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See detailA stochastic framework for subspace identification of a strongly nonlinear aerospace structure
Noël, Jean-Philippe ULg; Schoukens, Johan; Kerschen, Gaëtan ULg

in Proceedings of the International Modal Analysis Conference (IMAC) XXXII (2014, February)

The present study exploits the maximum likelihood identification framework for deriving statistically-optimal models of nonlinear mechanical systems. The identification problem is formulated in the ... [more ▼]

The present study exploits the maximum likelihood identification framework for deriving statistically-optimal models of nonlinear mechanical systems. The identification problem is formulated in the frequency domain, and model parameters are calculated by minimising a weighted least-squares cost function. Initial values of the model parameters are obtained by means of a nonlinear subspace algorithm. The complete identification methodology is first demonstrated on a Duffing oscillator, prior to being applied to a full-scale aerospace structure. [less ▲]

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See detailLiege acromegay Survey : An epidemiological study about the average age of death and the causes of mortality of acromegalic patients managed in liege
Petignot, S; PETROSSIANS, Patrick ULg; Daly, Adrian ULg et al

in Abstract book - Symposium "Perspectives in Endocrinology" Congresses Highlights 2013:ECE Copenhagen, ENDO SF, SFE Paris (2014, February)

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See detailIdentification of a Time-varying Beam Using Hilbert Vibration Decomposition
Bertha, Mathieu ULg; Golinval, Jean-Claude ULg

in Proceedings of the International Modal Analysis Conference (IMAC) XXXII (2014, February)

The present work is concerned by modal identification of time-varying systems. For this purpose, a method based on instantaneous frequency identification and synchronous demodulation is used to extract ... [more ▼]

The present work is concerned by modal identification of time-varying systems. For this purpose, a method based on instantaneous frequency identification and synchronous demodulation is used to extract modal components from recorded signals. The proposed method of iterated sifting process is based on the Hilbert Vibration Decomposition (HVD) technique which is used to extract the instantaneous dominant vibrating component at each iteration. A source separation preprocessing step is introduced to treat multiple degree-of-freedom systems in an optimal way. Sources are used as reference signals to get a single instantaneous frequency of each mode for the demodulation on all the channels. The algorithm is presented and is applied to numerical simulation of a randomly excited time-varying structure for illustration purpose. The investigated structure is made up of a beam on which a non-negligible mass is traveling. The variable location of the mass results in changes in modal parameters. [less ▲]

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See detailThe small Heat Shock Proteins (HSPs) response following eccentric exercise
Hody, Stéphanie ULg; Simonet, Arnaud; Lacrosse, Zoé ULg et al

in Abstract Book GIGA Day 2014 (2014, January 27)

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See detailSpray retention assment combining high-speed shadow imagery and fluorescence techniques
Massinon, Mathieu ULg; Boukhalfa, Hassina dite Hafida ULg; Lebeau, Frédéric ULg

in International Advances in Pesticide Application: Aspects of Applied Biology 122, 2014 (2014, January 08)

Droplet behaviour during impact affects retention by leaves. The increase of droplet adhesion to plant leaves is the objective when applying crop protection products, while droplet bouncing and ... [more ▼]

Droplet behaviour during impact affects retention by leaves. The increase of droplet adhesion to plant leaves is the objective when applying crop protection products, while droplet bouncing and fragmentation are usually seen as detrimental to spray retention. However, observation of droplet impacts on barley using high speed imaging showed that fragmentation impact outcome can occur in two different wetting regimes: Cassie-Baxter or Wenzel’s regime. In the latter, a fraction of the droplet is anchored in the surface roughness, what contributes to retention. Three mixtures were sprayed on excised barley leaves with an 11003 flat-fan nozzle operating at 0.2 MPa. Simultaneous measurements were performed using high speed imaging for droplet impact characterisation. A fluorescent tracer was added to the spray mixture for retention assessment. Retention was related to impact type considering the fraction of the droplet remaining on the leaf surface after a droplet splashing occurring in Wenzel’s wetting regime. This fraction varied from 28‒46% depending on the spray mixture and was correlated to the Volume Median Diameter DV0.5 of the impacting droplets. [less ▲]

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See detailNumerical Simulation of a Conical Shape Made By Single Point Incremental
Velosa De Sena, José ULg; Guzmán Inostroza, Carlos Felipe ULg; Duchene, Laurent ULg et al

in Incremental sheet forming (2014, January 06)

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See detailCompanion search around β Pictoris with the newly commissioned L'-band vector vortex coronagraph on VLT/NACO
Mawet, D.; Absil, Olivier ULg; Milli, J. et al

in Booth, Mark; Matthews, Brenda; Graham, James (Eds.) Exploring the Formation and Evolution of Planetary Systems (2014, January 01)

Here we present the installation and successful commissioning of an L'-band Annular Groove Phase Mask (AGPM) coronagraph on VLT/NACO. The AGPM is a vector vortex coronagraph made from diamond ... [more ▼]

Here we present the installation and successful commissioning of an L'-band Annular Groove Phase Mask (AGPM) coronagraph on VLT/NACO. The AGPM is a vector vortex coronagraph made from diamond subwavelength gratings tuned to the L' band. The vector vortex coronagraph enables high contrast imaging at very small inner working angle (here 0''.09, the diffraction limit of the VLT at L'), potentially being the key to a new parameter space. During technical and science verification runs, we discovered a late-type companion at two beamwidths from an F0V star (Mawet et al. 2013), and imaged the inner regions of β Pictoris down to the previously unexplored projected radius of 1.75 AU. The circumstellar disk was also resolved from ~= 1'' to 5'' (see J. Milli et al., these proceedings). These results showcase the potential of the NACO L-band AGPM over a wide range of spatial scales. [less ▲]

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See detailFirst High-Angular Resolution L' Images of the β Pictoris Debris Disc with the VLT / NaCo
Milli, Julien; Mawet, Dimitri; Absil, Olivier ULg et al

in Booth, Mark; Matthews, Brenda; Graham, James (Eds.) Exploring the Formation and Evolution of Planetary Systems (2014, January 01)

Imaging debris discs in the L'-band (3.8 μm) is a difficult task. Quasi-static speckles from imperfect optics prevail below 1'' whereas background emission is the dominant noise source beyond that ... [more ▼]

Imaging debris discs in the L'-band (3.8 μm) is a difficult task. Quasi-static speckles from imperfect optics prevail below 1'' whereas background emission is the dominant noise source beyond that separation and is much larger than at shorter wavelengths. We demonstrate here the potential of the newly commissioned AGPM coronograph on VLT/NaCo combined with advanced star and sky subtraction technique based on Principal Component Analysis, and we analyze the morphology of the β Pictoris disc. [less ▲]

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See detailThe VLTi/PIONIER survey of southern TTauri disks
Anthonioz, F.; Ménard, F.; Pinte, C. et al

in Booth, Mark; Matthews, Brenda; Graham, James (Eds.) Exploring the Formation and Evolution of Planetary Systems (2014, January 01)

Studying the inner regions of protoplanetary disks (1-10 AU) is of importance to understand the formation of planets and the accretion process feeding the forming central star. Herbig AeBe stars are ... [more ▼]

Studying the inner regions of protoplanetary disks (1-10 AU) is of importance to understand the formation of planets and the accretion process feeding the forming central star. Herbig AeBe stars are bright enough to be routinely observed by Near IR interferometers. The data for the fainter T Tauri stars is much more sparse. In this contribution we present the results of our ongoing survey at the VLTI. We used the PIONIER combiner that allows the simultaneous use of 4 telescopes, yielding 6 baselines and 3 independent closure phases at once. PIONIER's integrated optics technology makes it a sensitive instrument. We have observed 22 T Tauri stars so far, the largest survey for T Tauri stars to this date. Our results demonstrate the very significant contribution of an extended component to the interferometric signal. The extended component is different from source to source and the data, with several baselines, offer a way to improve our knowledge of the disk geometry and/or composition. These results validate an earlier study by Pinte et al. 2008 and show that the dust inner radii of T Tauri disks now appear to be in better agreement with the expected position of the dust sublimation radius, contrary to previous claims. [less ▲]

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See detailGeophysical Monitoring of Artificial Landslide Dam of Kambarata Hydro Power Plant-2 (Kyrgyzstan)
Torgoev, Isakbek; Havenith, Hans-Balder ULg; Torgoev, Almaz

in Landslide Science for a Safer Geoenvironment (2014, January 01)

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See detailThe Delta Ori Very Large Project: X-ray Emission and Stellar Variability
Corcoran, Michael F.; Nichols, J. S.; Moffat, A. F. et al

in American Astronomical Society Meeting Abstracts (2014, January 01)

Delt Ori is the nearest massive, single-lined eclipsing binary (O9. II+OB, $P=5^{d}.7324$). High resolution X-ray spectrometry combined with high-precision photometry from space offers a unique ... [more ▼]

Delt Ori is the nearest massive, single-lined eclipsing binary (O9. II+OB, $P=5^{d}.7324$). High resolution X-ray spectrometry combined with high-precision photometry from space offers a unique opportunity to geometrically measure the dynamics of the shocked gas around the primary star. We summarize our recent campaign of phase-constrained high-resolution X-ray spectra obtained with the CHANDRA/HETGS plus high-precision optical photometry with MOST. These observations provide local measurement of the distribution of the embedded, X-ray emitting shocks in the wind of an O star via radial velocity variations and occultation effects, along with standard $f/i$ ratio diagnostics, and enable us to look for correlations with the broad-band photometric variability. We discuss how these observations can help determine the primary star's clumping-corrected mass loss rate, and resolve critical uncertainties in our understanding of the connection between stellar and mass loss parameters. [less ▲]

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See detailHazard and risk related to earthquake-triggered landslide events
Havenith, Hans-Balder ULg

in Landslide Science for a Safer Geoenvironment (2014, January 01)

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See detailTime-Resolved X-ray Spectroscopy of the Massive Binary delta Ori
Nichols, Joy S.; Nazé, Yaël ULg; Corcoran, M. F. et al

in American Astronomical Society Meeting Abstracts (2014, January 01)

We have obtained 500 ks of Chandra HETG observations of the massive binary delta Ori (O9.5II+unseen companion), one of the fundamental calibrators of the mass-luminosity-radius relation in the upper HR ... [more ▼]

We have obtained 500 ks of Chandra HETG observations of the massive binary delta Ori (O9.5II+unseen companion), one of the fundamental calibrators of the mass-luminosity-radius relation in the upper HR diagram. The program is intended to map the emission line parameters as the secondary moves through the wind of the primary star. Custom extraction techniques have been developed to create 12 time-resolved 40 ks spectra from these observations, each of which is properly calibrated for time and temperature effects. Emission line fluxes for these time slice spectra are presented, as well as phase analysis of the variability of the fluxes. We discuss the interpretation of the resulting data, such as colliding winds and occultation of various temperature regimes of the primary wind by the secondary. [less ▲]

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See detailUnraveling the Mystery of Exozodiacal Dust
Ertel, S.; Augereau, J.-C.; Thébault, P. et al

in Booth, Mark; Matthews, Brenda; Graham, James (Eds.) Exploring the Formation and Evolution of Planetary Systems (2014, January 01)

Exozodiacal dust clouds are thought to be the extrasolar analogs of the Solar System's zodiacal dust. Studying these systems provides insights in the architecture of the innermost regions of planetary ... [more ▼]

Exozodiacal dust clouds are thought to be the extrasolar analogs of the Solar System's zodiacal dust. Studying these systems provides insights in the architecture of the innermost regions of planetary systems, including the Habitable Zone. Furthermore, the mere presence of the dust may result in major obstacles for direct imaging of earth-like planets. Our EXOZODI project aims to detect and study exozodiacal dust and to explain its origin. We are carrying out the first large, near-infrared interferometric survey in the northern (CHARA/FLUOR) and southern (VLTI/PIONIER) hemispheres. Preliminary results suggest a detection rate of up to 30% around A to K type stars and interesting trends with spectral type and age. We focus here on presenting the observational work carried out by our team. [less ▲]

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See detailL’associationnisme ethnique à l’épreuve du temps : étude de cas. Le Movimiento Asociativo de Emigrantes Españoles en Bélgica
Molina Marmol, Maïté ULg

in Actes des journée d’étude du 10 novembre 2011 « Immigration et troisième âge. Vieillir en migration, constats et solutions pour des populations silencieuses » (2014, January)

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See detailIntroduction: Natural Dams and Landslides in Reservoirs
Strom, A.; Havenith, Hans-Balder ULg; Wang, F.

in Landslide Science for a Safer Geoenvironment (2014, January)

Abstract: Introduction describes briefly main problems that are highlighted in the papers selected for the C9 session of the WLF3 “Natural dams and landslides in reservoirs”. Various aspects of ... [more ▼]

Abstract: Introduction describes briefly main problems that are highlighted in the papers selected for the C9 session of the WLF3 “Natural dams and landslides in reservoirs”. Various aspects of interaction between water bodies and surrounding slopes and of the stability of natural and artificial dams are discussed... [less ▲]

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See detailAnalysis of POPs in 20μL blood by MEPS-GC-MS/MS
L'Homme, Benjamin ULg; Focant, Jean-François ULg

in Hyphenated Techniques in Chromatography HTC-13 - Book of abstracts (2014, January)

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See detailReading the decomposition chemistry of human remains with a new pair of glasses
Stefanuto, Pierre-Hugues ULg; Stadler, s; Perrault, K et al

in Hyphenated Techniques in Chromatography HTC-13 - Book of abstracts (2014, January)

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See detailUse of rotary atomiser to optimize retention on barley leaves while reducing driftable droplets
Ouled Taleb Salah, Sofiene ULg; Massinon, Mathieu ULg; Boukhalfa, Hassina dite Hafida ULg et al

in International Advances in Pesticide Application, Aspects of Applied Biology 122 (2014, January)

Controlled Droplet Application using rotary atomiser is based on an improved control of droplet size and trajectory comparatively to hydraulic nozzles. On the basis of literature, it was stated that the ... [more ▼]

Controlled Droplet Application using rotary atomiser is based on an improved control of droplet size and trajectory comparatively to hydraulic nozzles. On the basis of literature, it was stated that the use of 60° forward angled spray combined with the narrow drop size distribution of a rotary atomiser could lead to low drift and high retention on monocotyledonous and superhydrophobic weeds at early stage. A Micromax120 atomiser was tuned to emit 270 µm VMD, 60° angled forward, to increase interception by the canopy structure. A spray mixture containing a superspreader adjuvant was used to avoid drop bouncing. An increase of spray retention comparatively to a Teejet 11002 at 1.4 bars was observed, although not proved statistically significant by these preliminary trials. On the drift side, the tilted spinning disc seemed to be advantageous since droplet spectra contains a low percentage of droplets under 100 µm and presents an ejection velocity of 25 m.s-1 at 5000 RPM. The spray drift was reduced about 50%. However, these setting were not found as efficient as expected. Indeed, angled spray proved to be more sensitive to advection and turbulence, as the spray was more exposed to the airflow than for the vertical position. It appears that angling the spray and choosing a drop size spectrum with a Volume Median Diameter as big as 270 µm is not sufficient to reduce significantly this issue. Some alternatives as decreasing the emission height are possible with angled sprays but require height control that seems difficult to reach in practical situations. [less ▲]

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See detailUn approccio sociolinguistico allo studio dell’emigrazione campana in provincia di Liegi (Belgio)
Moreno, Paola ULg

in Di Salvo, Margherita; Moreno, Paola; Sornicola, Rosanna (Eds.) Multilinguismo in contesto migratorio. Metodologia e progetti di ricerca sulle dinamiche linguistiche degli italiani all'estero (2014, January)

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See detailGC×GC-TOFMS identification of new cadaveric VOCs
Pesesse, Romain ULg; Stefanuto, Pierre-Hugues ULg; Stadler, S et al

in Hyphenated Techniques in Chromatography HTC-13 - Book of abstracts (2014, January)

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See detailEnhanced Multivariate Analysis of Mainstream Tobacco Smoke Particulate Phase by HS-SPME-GC×GC-TOFMS
Brokl, Michal ULg; Bishop, L; Wright, c et al

in Hyphenated Techniques in Chromatography HTC-13 - Book of abstracts (2014, January)

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See detailFast chromatographic method for explosives profiling
Stefanuto, Pierre-Hugues ULg; Perrault, K; Perrault, K et al

in Hyphenated Techniques in Chromatography HTC-13 - Book of abstracts (2014, January)

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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 detailAn agent-based micro-simulation framework to assess the impact of river floods on transportation systems: implementation trajectory for an assessment in the Brussels metropolitan area
Saadi, Ismaïl ULg; Eftekhar, Hamed ULg; Mustafa, Ahmed et al

in Proceedings of the International Conference for Traffic and Transport Engineering (ICTTE) Belgrade 2014 (2014)

Several studies were made to assess the direct damage but few studies tackled the topic related to the assessment of indirect damage. This paper discusses the development of a large scale agent-based ... [more ▼]

Several studies were made to assess the direct damage but few studies tackled the topic related to the assessment of indirect damage. This paper discusses the development of a large scale agent-based micro-simulation framework to assess the economic damage caused by river floods. The advantage of this approach is that the economic loss can be assessed at individual level. For that purpose, relationship is established between costs and trips cancelation/duration growth. As the numerical simulations depend largely on the initial demand, the accuracy of the data is fundamental. The model is based upon several disaggregated data related to mobility behaviour of the Belgian citizens. The study area covers the Brussels metropolitan area which was subjected to several floods in the past and may see the risk increasing in the coming decades. [less ▲]

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See detailLost and found: Rediscovery of de Ryckholt's collection of Cretaceous Mollusca (Belgium and N. France)
Fischer, Valentin ULg; Denayer, Julien ULg; Mottequin, Bernard ULg

in 4th International Palaeontological Congress, Mendoza, Abstracts volume (2014)

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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 detailOpérationnel et politique foncière : esquisse de commentaire
Donnay, Luc ULg

in Delnoy, Michel (Ed.) Le Code wallon de développement territorial (2014)

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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 detailTowards sustainable neighbourhoods: a new handbook and its application
Marique, Anne-Françoise ULg; Teller, Jacques ULg

in Marchettini, M; Brebbia, C.A.; Pulselli, R.M. (Eds.) The Sustainable City IX : Urban Regeneration and Sustainability (2014)

This paper presents a practical handbook that aims at helping local authorities and private developers to build and assess “sustainable neighbourhoods” in Wallonia (Belgium). This handbook was developed ... [more ▼]

This paper presents a practical handbook that aims at helping local authorities and private developers to build and assess “sustainable neighbourhoods” in Wallonia (Belgium). This handbook was developed by the Research Centre on Territorial, Urban and Rural Sciences (Lepur, University of Liège), at the request of the Walloon Minister of the Environment, Spatial Planning and Mobility. The concrete aim of the handbook is to concretely define the concept of "sustainable neighbourhood" by clearly tagging the minimum criteria that a real estate project must meet to obtain the “sustainable neighbourhood” label in Wallonia. It is a tool for decision support in the design as well as the evaluation of real estate projects, since the early stages of their design. The handbook is structured into 5 main theme and 25 criteria of sustainability. In a broad vision of sustainability, this handbook is not strictly limited to energy issues but considers "sustainability" in all its multiple components: location, network connection, mobility of inhabitants, use of natural resources, landscaping, waste management, diversity of function, social interactions, among others. The handbook is firstly presented and, then, applied to 12 recent case studies in order to identify common invariants in the design process of “sustainable neighbourhoods” and barriers to the integration of cross-cutting principles of sustainability in neighbourhood projects. Our main results namely show that the criteria dealing with energy performance of buildings and green spaces have percolated in many cases. However, the diversity of housing types, the accessibility to handicapped peoples, social diversity and participation issues remain poorly addressed in most of the cases studies. [less ▲]

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See detailLuminescence dating of ceramic building materials: application to the study of early medieval churches in north-western France and south-eastern England
Blain, Sophie ULg; Bailiff, Ian; Guibert, Pierre et al

in Martinón-Torres, Marcos (Ed.) Between craft and science: selected studies in archaeological ceramics (2014)

This study focuses on early medieval buildings in England and in France, specifically on those displaying the presence of brick in their masonry. The purpose was to determine whether medieval builders ... [more ▼]

This study focuses on early medieval buildings in England and in France, specifically on those displaying the presence of brick in their masonry. The purpose was to determine whether medieval builders reused Roman salvaged building materials or if the bricks used were contemporary to the building under construction. Thus luminescence dating was applied to bricks sampled from 11 standing Anglo-Saxon or Carolingian churches. The luminescence dates show that the two types of practice were in use in both countries. Where contemporary brickmaking appears to be the case, the study also provided a more precise chronology of the buildings. [less ▲]

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See detailMarquage casuel des dépendants nominaux du verbe en ancien français: approche dépendancielle
Mazziotta, Nicolas ULg

in Neveu, Franck; Blumenthal, Peter; Gerstenberg, Annette (Eds.) et al 4e Congrès Mondial de Linguistique Française. Berlin, Allemagne, 19-23 Juillet 2014 (2014)

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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 detailAnalyse exploratoire des propriétés sémantiques et syntaxiques des verbes « psychologiques » (classe P) dans Les Verbes Français
Mazziotta, Nicolas ULg

in Née, Émilie; Daube, Jean-Michel; Valette, Mathieu (Eds.) et al Actes des 12es Journées internationales d’Analyse statistique des Données Textuelles (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 detailComment Descartes et Leibniz (disent qu'ils) lisent les philosophes
Bouquiaux, Laurence ULg

in Les arts de lire des philosophes. Théorie et pratique de la lecture des textes chez les philosophes de l’âge classique (2014)

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See detailLe fonti liturgiche di Peire d’Alvernhe, 'Deus, vera vida, verays' (BdT 323,16)
Valenti, Gianluca ULg

in Los que fan viure e treslusir l’occitan. Actes du Xème Congrès de l’Association Internationale d’Etudes Occitanes (Béziers, CIRDOC, 12-19/06/2011) (2014)

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See detailImplicit implementation of the Prevost model
Cerfontaine, Benjamin ULg; Charlier, Robert ULg

in Hicks, Michael A.; Brinkgreve, Ronald, R.J; Rohe, Alexander (Eds.) Numerical Methods in Geotechnical Engineering (2014)

The Prevost model for cohesionless soils (Prevost 1985) is currently used for the modelling of their cyclic behaviour, especially in earthquake engineering (Zerfa and Loret 2003) and (Yang and Elgamal ... [more ▼]

The Prevost model for cohesionless soils (Prevost 1985) is currently used for the modelling of their cyclic behaviour, especially in earthquake engineering (Zerfa and Loret 2003) and (Yang and Elgamal 2008). It’s made of conical yield surfaces that allow for plastic deformations in both loading and unloading. Its non-associated volumetric flow rule can roughly take into account pore pressure build-up and cyclic mobility. The method of implementation of a constitutive law is a crucial issue (Montáns and Caminero 2007) and (Mira et al. 2009). On one hand the accuracy of the solution must be ensured, especially when a large number of cycles are considered. But on the other hand, the cost of the computation must be minimized which implies step size as large as possible. In this paper, an implicit implementation of the Prevost model is proposed. The plastic flow rule is computed through a trapezoidal rule, at the time step n + 1/2, in order to increase the accuracy.An iterative process has to be solved, due to the implicit formulation.The Jacobian matrix of the internal Newton-Raphson process is computed analytically to enhance efficiency. The algorithm is implemented in the finite element code LAGAMINE that carries out fully-coupled analysis. Simulations of triaxial tests are compared with “exact” solution. [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 detailImage politique et rapports de farce: L'exemple de la "Daerdenmania"
Devresse, Jenifer ULg

in Veyrat-Masson, Isabelle; Denis, Sébastien; Sécail, Claire (Eds.) Sous les images, la politique... Presse, cinéma, télévision, nouveaux médias (XXe-XXIe siècle) (2014)

Narguant les douces utopies démocratiques projetées sur les dispositifs des NTIC, les nouvelles pratiques liées à l’Internet font la part belle au divertissement, et la politique n’y échappe guère ; en ... [more ▼]

Narguant les douces utopies démocratiques projetées sur les dispositifs des NTIC, les nouvelles pratiques liées à l’Internet font la part belle au divertissement, et la politique n’y échappe guère ; en témoigne notamment la fréquentation considérable des formes virtuelles du bêtisier politique (vidéos Youtube, etc.), devançant de loin celle des sites politiques ou citoyens. À cet égard, le cas de la « Daerdenmania » est particulièrement interpellant. Le socialiste belge Michel Daerden, baptisé « le Gainsbourg de la politique », connaît grâce à Internet une popularité internationale surprenante qui ne doit rien assurément à ses qualités proprement politiques, mais plutôt à ses qualités de pitre qui en font le héros d’une foultitude de plaisanteries. Or ce phénomène, bien plus qu’une exception à la belge, ne serait-il pas le révélateur d’un mouvement plus général, lié à une personnalisation du politique à la fois exacerbée et transfigurée par les usages émergents des NTIC ? L’exemple des images « daerdenmaniaques » permet d’explorer quelques modalités du rapport contemporain à la politique et témoignerait, non d’un renouveau de l’engagement citoyen dans les rapports de force politiques, mais au contraire d’un désengagement en termes de rapport de farce à la chose politique. En ce sens, ces formes communes de dérision signifieraient l’endormissement croissant de la possibilité du jugement critique, proprement politique, au profit d’une communauté émotionnelle. [less ▲]

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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; Basheer, Muhammed; Magee, Bryan (Eds.) et al Proceedings of Concrete Solutions (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 detailPatch repair: compatibility issues
Garbacz, Andrzej; Courard, Luc ULg; Bissonnette, Benoît et al

in Grantham, Michael; Basheer, Muhammed; Magee, Bryan (Eds.) et al Proceedings of the 5th International Conference on Concrete Repair (2014)

Repair of any concrete structure results in formation of complex, at least two-component repair systems. Compatibility approach is treated as a basic requirement during selection of repair material ... [more ▼]

Repair of any concrete structure results in formation of complex, at least two-component repair systems. Compatibility approach is treated as a basic requirement during selection of repair material. Recently, the understanding for compatibility requirements in repair systems approach is demonstrated in many papers. The aim of this paper is analyzing the compatibility between repair materials and concrete substrate in the case of patch repair. The compatibility issues were discussed in light of the various requirements which determine the mathematical space of loads, including chemical, mechanical and other physical (mainly thermal) loads. N-dimensional compatibility space is created, taking into account selected patch material control parameters. The requirements for good compatibility between repair material and concrete substrate can be formulated by using mathematical inequalities, where the variables are the material control parameters. The effects of properties of the both repair material and concrete substrate were analyzed using computer system ANCOMP developed at Warsaw University of Technology. Usability of this approach was demonstrated using selected case study as an example. [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 detailImproving the Energy Efficiency of the Building Stock: A Bottom-up Model and its Application in an Online Interactive Portal
Cuvellier, Simon; Marique, Anne-Françoise ULg; Reiter, Sigrid ULg

in Proceedings of PLEA 2014 (2014)

There is an urgent need to reduce energy uses in new and retrofitted buildings. In Europe, energy consumption in the building sector still represents more than 40% of the final energy use. Emerging ... [more ▼]

There is an urgent need to reduce energy uses in new and retrofitted buildings. In Europe, energy consumption in the building sector still represents more than 40% of the final energy use. Emerging countries are also concerned by such issues at even wider levels because of the huge demographic growth they are witnessing. Numerous research studies have highlighted the need to produce more efficient buildings, but also to retrofit the existing building stock. However, research methods and tools that allow a precise quantification of energy uses in buildings and energy savings related to various actions (insulating the roofs, changing the glazing, behavioral changes, etc.) are mainly dedicated to trained professional users, thus neglecting the huge potential energy savings that is linked to individual actions undertaken by citizens in their dwellings. In this context, the main aim of our research is to raise awareness of energy efficiency in residential buildings and encourage positive changes to the energy efficiency of the building stock, starting at the individual scale. This paper first presents the methodology that allows a precise energy assessment (heating, cooling, ventilation, lighting, appliances and cooking) of buildings (at the house, neighborhood, city and region scales) on the basis of a “bottom-up” approach. This methodology uses a typological classification of buildings, thermal simulations and local surveys. In this paper, this methodology is applied to the Walloon (Belgium) building stock. Many parameters are defined and taken into account to capture the specificities of numerous types of buildings (e.g., the number of floors, common ownership, orientation, thermal performances, ventilation, etc.). Several occupation modes are modelled to capture the impact of occupants’ behavior on energy consumption. To take into account the impact of urban form, correction factors are defined and applied according to the type of neighborhoods in which the buildings are located. All things considered, 250,000 individual results are obtained and stored in a huge database. Linear extrapolations and correction factors are used to extrapolate and apply these results to any type of residential building in Wallonia. This methodology is then used to develop an online portal that aims to strengthen citizens’ awareness of the necessity for ecological changes in the building sector and encourage individual actions to improve the energy efficiency of buildings. This tool allows for a transfer of the main results of a two-year scientific research effort to citizens in a very simple and intuitive way. Although the results presented in this paper are focused on Wallonia (Belgium), the research is easily reproducible to other territories by adapting local parameters. [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 detailEffect of inhaled hysrosoluble curcumin in lipopolysaccharide-induced lung neutrophilia in horses
Sandersen, Charlotte ULg; Cerri, Simona ULg; Franck, Thierry ULg et al

in Dorothy Russel Havemeyer Foundation IAD Workshop (2014)

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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 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 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 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 detailLe miroitement des mots
Verbeeck, Muriel ULg; Buyle, Marjan

in Buyle, Marjan (Ed.) Lustre et brillance en conservation-restauration - Glans in de conservait-restauratie (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 detailTsunamis triggered the Late Frasnian Kellwasser extinction event
Poty, Edouard ULg; Denayer, Julien ULg; Mottequin, Bernard ULg

in 4th International Palaeontological Congress, Mendoza, Abstracts volume (2014)

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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 detailDistinction by micro-Raman spectroscopy and chemometrical analysis of copper phthalocyanine blue polymorphs in oil-based and acrylic samples
Defeyt, Catherine ULg; Van Pevenage, Jolien; Learner, Tom et al

in Van den berg, K.J.; Burnstock, A.; de Tagle, A. (Eds.) et al Issues in Contemporary Oil Paints (2014)

Copper phthalocyanine (CuPc) blue, commonly named phthalo blue is the most important synthetic organic blue pigment in the 20th and 21st century artists paints. Phthalo blue, which is adopted by artists ... [more ▼]

Copper phthalocyanine (CuPc) blue, commonly named phthalo blue is the most important synthetic organic blue pigment in the 20th and 21st century artists paints. Phthalo blue, which is adopted by artists since 1936, is a polymorphous pigment. Currently, the alpha, beta and epsilon CuPc polymorphs are used in artists paint formulations. The identification of the CuPc crystal form provides technical and chronological information relevant for studying artworks. Raman Spectroscopy (RS) is a very valuable technique for the detection of phthalo blue in paint layers. However, the spectral interpretation is not straightforward concerning the CuPc polymorph distinction. To overcome the problem we have previously developed a procedure combining RS and chemometrical analysis. The experimental results that we obtained have demonstrated its efficiency for predicting the CuPc crystal form in unknown paint samples. In the present work, this procedure was applied on oil-based and acrylic paints from Sam Francis’ studio and the Getty Conservation Institute (GCI) Reference Collection. [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 detailPremière évaluation des impacts des poussières désertiques sur la santé des enfants en Afrique de l’Ouest : étude de cas dans le Bénin septentrional
De Longueville, Florence ULg; Henry, Sabine; Ozer, Pierre ULg

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

Le Sahara est à l’origine de plus de la moitié des aérosols désertiques présents dans l’atmosphère. Ces aérosols terrigènes diminuent la visibilité horizontale et augmentent les concentrations en ... [more ▼]

Le Sahara est à l’origine de plus de la moitié des aérosols désertiques présents dans l’atmosphère. Ces aérosols terrigènes diminuent la visibilité horizontale et augmentent les concentrations en particules de taille inférieure à 10 µm (PM10), qui font partie de la catégorie des particules respirables. Un nombre croissant d’études démontrent des impacts significatifs des épisodes de poussières désertiques sur la santé mais aucune étude n’a été menée en Afrique de l’Ouest. Cette étude est la première qui vise à évaluer les impacts réels des aérosols sahariens sur la qualité de l’air et la santé respiratoire dans cette partie du monde. La combinaison de deux sources d’informations a permis de déterminer les épisodes de poussières ayant affecté la région de Kandi (Bénin septentrional) en saison sèche durant la période 2003-2007. Sur l’ensemble de cette période, 61 jours d’épisodes de poussières ont été notés. Les concentrations journalières en PM10 ont été multipliées par 18,5 lors de ces épisodes, ce qui contribue à dépasser de très loin les normes de l’OMS fixant un seuil de concentration annuelle maximale de 20 µg.m-3. Sur la base de données mensuelles de consultations des enfants pour infections respiratoires aiguës basses (IRAB), nous avons calculé une augmentation de 12,5% des taux mensuels d’IRAB dans la région de Kandi durant les mois ayant enregistré un épisode de poussières. Même si cette augmentation est loin d’être négligeable, elle apparaît relativement limitée par rapport aux impacts auxquels on pourrait s’attendre compte tenu des concentrations en PM10 atteintes. Ainsi, il est nécessaire de multiplier les recherches en Afrique de l’Ouest afin de mieux quantifier les impacts des aérosols désertiques sur la santé des populations qu’elle abrite. [less ▲]

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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 detailEtude longitudinale des besoins psychosociaux de personnes atteintes de cancer : Hiérarchisation et résolution de problème
Wagener, Aurélie ULg; Jonius, Bénédicte; DEVOS, Martine ULg et al

in Christophe, Véronique; Ducro, Claire; Antoine, Pascale (Eds.) Psychologie de la santé : Individu, famille et société (2014)

INTRODUCTION. L’existence et l’importance des besoins psychosociaux vécus par les conjoints de personnes atteintes de cancer ont été mises en évidence à plusieurs reprises. Afin de diminuer ces besoins ... [more ▼]

INTRODUCTION. L’existence et l’importance des besoins psychosociaux vécus par les conjoints de personnes atteintes de cancer ont été mises en évidence à plusieurs reprises. Afin de diminuer ces besoins, notre recherche-action teste l’efficacité de la combinaison de deux méthodes d’action : la hiérarchisation des besoins puis la résolution de problème ajustée à ces besoins. MÉTHODOLOGIE. Notre étude, longitudinale, randomisée, comporte trois temps d’évaluations séparés de trois semaines (T0, T1 et T2) et deux groupes (expérimental et contrôle). Au T0, les deux groupes réalisent la hiérarchisation des besoins. Entre T0 et T1, le groupe expérimental bénéficie de la résolution de problème. Entre T1 et T2, le groupe contrôle reçoit, à son tour, cette méthode. Les questionnaires administrés aux différents temps d’évaluation sont : données sociodémographiques, Hospital Anxiety and Depression Scale (HADS), Psychosocial Needs Inventory (PNI), questionnaire relatif au sentiment d’autoefficacité (GSES). HYPOTHESES. Entre T0 et T1, une amélioration générale des scores est attendue dans les deux groupes : celle-ci devrait s’avérer plus importante dans le groupe expérimental, ayant réalisé la résolution de problème. Entre T1 et T2, les scores du groupe contrôle, ayant alors pratiqué cette méthode, devraient s’améliorer et rejoindre ceux obtenus par le groupe expérimental au T1.RÉSULTATS. Trente-sept personnes ont accepté de participer : groupe expérimental (N=19, hommes=12, femmes=7) et groupe contrôle (N=18, hommes=11, femmes=7). Les groupes expérimental et contrôle présentent respectivement une moyenne d’âge de 59 et de 58 ans. Au T0, les scores moyens sur la HADS sont de 11,95 pour le groupe expérimental et de 13,94 pour le groupe contrôle ; le nombre moyen de besoins psychosociaux sur le PNI est de 29 dans les deux groupes ; les moyennes sur la GSES sont de 33,53 pour le groupe expérimental et de 32,33 pour le groupe contrôle. La récolte des données se poursuit et nous réaliserons des analyses de type ANOVA à mesures répétées afin d’évaluer les changements en fonction du temps (T0, T1 et T2) et du groupe (expérimental vs contrôle). [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 detailLe Candide anglois: un cas complexe de "palimpseste"
Tilkin, Françoise ULg

in Cronk, Nicholas; Ferrand, Nathalie (Eds.) Les 250 ans de Candide. Lectures et relectures (2014)

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See detailThe Hangenberg Event (uppermost Famennian) in southern Belgium (Namur-Dinant Basin)
Mottequin, Bernard ULg; Poty, Edouard

in Cerdena, Esperanza (Ed.) 4th International Palaeontological Congress, Abstract Volume (2014)

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See detailAxisymmetric transient modelling of a suction caisson in dense sand
Cerfontaine, Benjamin ULg; Levasseur, Séverine ULg; Collin, Frédéric ULg et al

in Hicks, Michael A.; Brinkgreve, Ronald, B.J.; Rohe, Alexander (Eds.) Numerical Methods in Geotechnical Engineering (2014)

Suction caisson are hollow cylinders open towards the bottom that are currently used as anchors for deep water offshore facilities. They recently turned out to be advantageously exploited as foundation ... [more ▼]

Suction caisson are hollow cylinders open towards the bottom that are currently used as anchors for deep water offshore facilities. They recently turned out to be advantageously exploited as foundation for offshore wind turbines in shallow water (Senders 2009). The Prevost model for cohesionless soils (Prevost 1985) is currently used for the modelling of their cyclic behaviour. It’s able to reproduce plastic deformation in both loading and unloading, contractancy of the soil and pore pressure build up as well. In this paper, a fully- coupled transient axisymmetric analysis of a suction caisson is carried out. A vertical pseudo-random loading is transformed into equivalent ones. Comparison of the permanent displacement accumulated shows a good agreement between them. The influence of the interface conditions is also addressed. For low tension amplitude applied to the caisson, it can be modelled as “stuck” to the inner soil. However higher amplitude might lead to a total unplugging. [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 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 detailStratigraphy and depositionnal settings of the Late Famennian of Southern Belgium - a snapshot of the palaeoenvironment for late Devonian tetrapods and arthropods
Denayer, Julien ULg; Prestianni, Cyrille; Olive, Sébastien et al

in 4th International Palaeontological Congress, Mendoza, Abstracts volume (2014)

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See detailSimultaneous perturbation algorithms for batch off-policy search
Fonteneau, Raphaël ULg; Prashanth L.A.

in Proceedings of the 53rd IEEE Conference on Decision and Control (IEEE CDC 2014) (2014)

We propose novel policy search algorithms in the context of off-policy, batch mode reinforcement learning (RL) with continuous state and action spaces. Given a batch collection of trajectories, we perform ... [more ▼]

We propose novel policy search algorithms in the context of off-policy, batch mode reinforcement learning (RL) with continuous state and action spaces. Given a batch collection of trajectories, we perform off-line policy evaluation using an algorithm similar to that in [Fonteneau et al. (2010)]. Using this Monte-Carlo like policy evaluator, we perform policy search in a class of parameterized policies. We propose both first order policy gradient and second order policy Newton algorithms. All our algorithms incorporate simultaneous perturbation estimates for the gradient as well as the Hessian of the cost-to-go vector, since the latter is unknown and only biased estimates are available. We demonstrate their practicality on a simple 1-dimensional continuous state space problem. [less ▲]

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

in Lepoint, Gilles; Michel, Loïc; Schnitzler, Joseph (Eds.) et al Zoology 2014 (2014)

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

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

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See detailEvolution récente des extrêmes pluviométriques en Mauritanie (1933-2010)
Ozer, Pierre ULg; Hountondji, Yvon-Carmen; Gassani, Jean et al

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

Un ensemble d’indicateurs a été compilé pour vérifier si la fréquence et/ou l’intensité des précipitations a significativement évolué au cours des dernières décennies dans la République Islamique de ... [more ▼]

Un ensemble d’indicateurs a été compilé pour vérifier si la fréquence et/ou l’intensité des précipitations a significativement évolué au cours des dernières décennies dans la République Islamique de Mauritanie. Cette étude s’appuie sur des indices nationaux basés les séries quotidiennes de précipitations de neuf stations synoptiques qui couvrent la période 1933-2010. L’analyse des précipitations a été réalisée en calculant annuellement treize indices pluviométriques : le total pluviométrique (PTOT), le nombre total de jours humides (précipitations ≥1 mm, JP), la lame d’eau moyenne précipitée par jour humide (Simple day intensity index, SDII), la pluviométrie maximale enregistrée sur 1 jour (Px1J), la fréquence des événements pluviométriques ≥ 10 mm (P10), ≥ 20 mm (P20), intenses (P95) et extrêmes (P99). Le poids relatif des cinq derniers indices dans le total pluviométrique annuel étant également apprécié. Les résultats montrent que les indices PTOT, JP, P10 et P20 présentent une tendance à la baisse significative sur la période 1933-2010. Dans le même temps, la fréquence des précipitations intenses et extrêmes évolue peu. De facto, la lame d’eau moyenne précipitée par jour humide (SDII) augmente de manière significative. Les résultats obtenus vont dans le sens des conclusions du Groupe d’expert intergouvernemental sur l’évolution du climat (Giec) à l’échelle globale, à savoir des précipitations extrêmes inchangées dans un contexte global de dessiccation. Selon de nombreux modèles, la dégradation pluviométrique pourrait s’amplifier dans les décennies à venir. Dès lors, des stratégies d’adaptation transfrontalières devraient être envisagées d’urgence car le processus de réchauffement de la planète n'est pas susceptible de diminuer dans les prochaines décennies. [less ▲]

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See detailThermoCycle: A Modelica library for the simulation of thermodynamic systems
Quoilin, Sylvain ULg; Desideri, Adriano ULg; Wronski, Jorrit et al

in Proceedings of the 10th International Modelica Conference 2014 (2014)

This paper presents the results of an on-going project to develop ThermoCycle, an open Modelica library for the simulation of low-capacity thermodynamic cycles and thermal systems. Special attention is ... [more ▼]

This paper presents the results of an on-going project to develop ThermoCycle, an open Modelica library for the simulation of low-capacity thermodynamic cycles and thermal systems. Special attention is paid to robustness and simulation speed since dynamic simulations are often limited by numerical constraints and failures, either during initialization or during integration. Furthermore, the use of complex equations of state (EOS) to compute thermodynamic properties significantly decreases the simulation speed. In this paper, the approach adopted in the library to overcome these challenges is presented and discussed. [less ▲]

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See detailModeling of Excavation Damaged Zone through the strain localization approach in Boom clay
Salehnia, Fatemeh ULg; Charlier, Robert ULg; Sillen, Xavier et al

in Proceedings of the 14th Int. Conference of International Association for Computer Methods and Recent Advances in Geomechanics, IACMAG 2014 (2014)

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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 detailRobust rendez-vous planning using the scenario approach and differential flatness
Dell'Elce, Lamberto ULg; Kerschen, Gaëtan ULg

in Advances in the Astronautical Sciences (2014)

There is a growing interest in uncertainty handling in the spacecraft dynamics community. In particular, robust optimization of spacecraft maneuvers is regarded as an important challenge. This paper ... [more ▼]

There is a growing interest in uncertainty handling in the spacecraft dynamics community. In particular, robust optimization of spacecraft maneuvers is regarded as an important challenge. This paper proposes an optimal control approach for orbital rendez-vous planning under stochastic dynamics and constraints. The method combines differential flatness theory with the scenario approach for optimization under uncertainties. By mapping state and control variables into a set of flat outputs, the enforcement of dynamics equations and boundary conditions is automatically satisfied. The rigorous foundations of the scenario approach lead to a finite-dimensional formulation of the problem which guarantees the feasibility of the solution within an arbitrary portion of the stochastic domain. The methodology is illustrated by means of two case studies involving a rendez-vous in elliptic orbit and a propellantless maneuver using differential drag, respectively. [less ▲]

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See detailL'élevage des ruminants, un élément clé de notre territoire
Hautier, Louis; Campion, Morgane; Ninane, Maxime ULg et al

in Centre wallon de Recherches agronomiques (Ed.) 19ème Carrefour des Productions Animales "La viande bovine remise en question : de sa production à sa consommation", Gembloux, le 19 février 2014 (2014)

Parallèlement à l'extension de l'agriculture, l'élevage s'est développé pour la fourniture de produits alimentaires (lait, viande) et non alimentaires (cuir, laine) mais également par l'apport de la ... [more ▼]

Parallèlement à l'extension de l'agriculture, l'élevage s'est développé pour la fourniture de produits alimentaires (lait, viande) et non alimentaires (cuir, laine) mais également par l'apport de la traction animale aux agriculteurs et la restitution d'éléments fertilisants. Ceci a notamment contribué, dans nos régions, au développement du système à jachère et culture attelée. Au cours des dernières décennies, l'agriculture s'est fortement intensifiée grâce à l'énergie fossile utilisée pour la production d'intrants, de concentrés, la mécanisation et le transport des produits alimentaires. Cette intensification de l'agriculture au niveau mondial a conduit à la spécialisation des exploitations avec une dissociation de l'élevage et de la culture en bassins de production avec des conséquences très dommageables sur l'environnement. De nos jours, les productions bovines représentent 54 % des principales orientations technico-économiques en Wallonie, selon la nouvelle classification européenne (OTEX). L'élevage bovin en production est composé de 500 601 têtes : 41 % de laitières et 59 % d'allaitantes. Il est fortement basé sur la valorisation des prairies permanentes qui occupent plus de 45 % de la surface agricole utile et concerne plus de 86 % des exploitations agricoles wallonnes sur les 13 301 recensées en 2012.Toutefois, l'élevage est de plus en plus critiqué par la société à cause de ses impacts négatifs sur l'environnement et de considérations liées au bien-être animal.De plus, dans certaines exploitations, mise en concurrence des zones de grandes cultures avec les zones herbagères pour la production de lait et viande, difficultés et contraintes du métier d'éleveur. L'arrêt de cette activité pose la question du devenir de la surface agricole qui lui était allouée. Dans ce contexte, il paraît important de passer ici en revue les principaux services liés à l'élevage de ruminants en Wallonie afin d'identifier par la suite les conditions qui permettent l'optimisation de ces derniers tout en limitant les nuisances connexes et ceci dans le but d'objectiver la situation. [less ▲]

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See detailFrom centralization to local policies: design reform dynamics in Belgium and the creation of Antwerp's Higher Institute (1830-1914)
Prina, Daniela ULg

in Tradition, Transition, Trajectories: Major or Minor Influences? ICDHS 9th International Conference for Design History and Design Studies 2014, Conference Proceedings (2014)

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See detailThe Relation Between The Food Price And The Climatic and Agricultural Factors In Republic of Niger
Andres, Ludovic ULg; Du Faux, Judith ULg; Lebailly, Philippe ULg

in Akın Olgun, F.; Kurtović, Mirsad; Filya, Ismail (Eds.) 25th International Scientific-Experts Congress on Agriculture and Food Industry : Book of abstracts (2014)

In the republic of Niger, the food price is very important for the farmers because the agricultural and livestock activities represent the main income of rural population. Furthermore, the temporary ... [more ▼]

In the republic of Niger, the food price is very important for the farmers because the agricultural and livestock activities represent the main income of rural population. Furthermore, the temporary disruptions (climate, environment) influence the food price. The target of this paper is to demonstrate the evolution of the millet current prices and the link between the prices and the annual temporary disruptions. The first factor is the monthly current prices of millet because it is the main food consumed by the rural population. The period taken into consideration is twenty years. The second factor is the annual precipitation and the number of raining days. The third factor is based on the millet production (production, yield, area). In the first time, we analyze the time series of monthly prices of millet with a mixed model. In the second time, an correlation compares the link between the “environmental” factors and the prices series. In conclusion, the time series studies of millet prices have demonstrated the cycle of these and their seasonality. Furthermore, the correlation has showed a difference between the studied factors and the millet prices. The main result is the demonstration of two time period: higher prices (May to August) and lower prices (October to January). [less ▲]

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See detailL’Alfier nero (Le Fou noir) d’Arrigo Boito – Lecture anthropologique et poétologique d’un combat d’échecs.
Leyh, Valérie ULg

in Achim Küpper, Kristine Vanden Berghe (Ed.) Guerre et jeu. Cultures d’un paradoxe à l’ère moderne (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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