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

Scientific conference (2015, July)

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

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

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See detailHPAEC-PAD profiles of maltooligosaccharide produced by hydrolysis of sorghum starches using amylases from various sources
Boudries, Nadia; Sindic, Marianne ULg; Belhaneche-Bensemra, Naima et al

in International Journal of Biotechnology and Food Science (2015), 3 (4)

Starches isolated from white and pigmented sorghum (Sorghum bicolor (L.) Moench) were used to determine enzymatic activity of starch hydrolysis by fungal (Aspergillus Oryzae) and bacterial (Bacillus ... [more ▼]

Starches isolated from white and pigmented sorghum (Sorghum bicolor (L.) Moench) were used to determine enzymatic activity of starch hydrolysis by fungal (Aspergillus Oryzae) and bacterial (Bacillus Subtilis) α-amylase and oligosaccharides profiles of hydrolysate was determinate in same conditions by High Performance Exchange Anion Chromatography with Pulsed Amperometric Detection (HPEAC-PAD). Pure starches from potato, amylose and amylopectin were used for comparison. Oligosaccharide compositions ranging from glucose (DP1) to maloheptaose (DP7) as well as the significantly effect of α-amylase source and starch structure were determined. [less ▲]

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See detailAlignments of quasar axes with large-scale structures
Hutsemekers, Damien ULg; Braibant, Lorraine ULg; Pelgrims, Vincent ULg et al

Conference (2015, July)

Based on measurements of optical linear polarization of quasars belonging to large groups at redshift ~ 1.3, we found that quasar spin axes are likely parallel to their host large-scale structures. The ... [more ▼]

Based on measurements of optical linear polarization of quasars belonging to large groups at redshift ~ 1.3, we found that quasar spin axes are likely parallel to their host large-scale structures. The observations and the statistical analysis will be reviewed, and interpretations discussed. [less ▲]

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

Conference (2015, July)

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

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

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

Poster (2015, July)

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

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

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See detailFlora and fauna from a new Famennian (Upper Devonian) locality at Becco, eastern Belgium
Olive, Sébastien; Clément, Gaël; Denayer, Julien ULg et al

in Geologica Belgica (2015), 18(2-4), 92-101

The Becco locality (Liège province), belongs to the Theux tectonic window and represents a proximal, probably fluvial, environment corresponding to a channel infill. We present here a preliminary report ... [more ▼]

The Becco locality (Liège province), belongs to the Theux tectonic window and represents a proximal, probably fluvial, environment corresponding to a channel infill. We present here a preliminary report of the fossil assemblage discovered at the locality. The Becco site has yielded a diverse flora of early seed plants including Moresnetia zalesskyi, Dorinnotheca streeli and Condrusia sp. This assemblage, characteristic of the Belgian Famennian, highlights the diversity of early spermatophytes in the country. Becco has also delivered a rich vertebrate fauna with antiarch, groenlandaspid and phyllolepid placoderms, diplacanthiform acanthodians, as well as actinopterygians and various sarcopterygians. The fossiliferous assemblage of Becco resembles those of several Devonian tetrapod- bearing localities, including that of Strud in Belgium, and could therefore provide a favorable palaeoecological setting in the search for early tetrapods. [less ▲]

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

Poster (2015, July)

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See detailBiogeographic variations in wood mice: Testing for the role of morphological variation as a line of least resistance to evolution
Renaud, Sabrina; Quere, Jean Pierre; Michaux, Johan ULg

in Cox, Philippe; Hautier, Lionel (Eds.) Cambridge Studies in Morphology and Molecules: New Paradigms in Evolutionary Biology ‘Evolution of the Rodents: Advances in Phylogeny, Paleontology and Functional Morphology’ (2015)

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See detailIntroduction
Brioist, Pascal; Fagnart, Laure ULg; Michon, Cédric

in Brioist, Pascal; Fagnart, Laure; Michon, Cédric (Eds.) Louise de Savoie 1476-1531 (2015)

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See detailLouise de Savoie et la chambre des "Bucoliques"
Fagnart, Laure ULg

in Brioist, Pascal; Fagnart, Laure; Michon, Cédric (Eds.) Louise de Savoie 1476-1531 (2015)

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See detailLouise de Savoie 1476-1531
Brioist, Pascal; Fagnart, Laure ULg; Michon, Cédric

Book published by Presses universitaires François-Rabelais de Tours / Presses universitaires de Rennes (2015)

Comtesse puis duchesse d’Angoulême, Louise de Savoie (1476-1531) n’est pas seulement la mère de deux enfants illustres, Marguerite (future reine de Navarre) et François (futur François Ier). Avant ... [more ▼]

Comtesse puis duchesse d’Angoulême, Louise de Savoie (1476-1531) n’est pas seulement la mère de deux enfants illustres, Marguerite (future reine de Navarre) et François (futur François Ier). Avant l’avènement de son fils, elle est l’une des familières de Louis XII et de sa cour ; une fois son « César » devenu roi de France, elle est omniprésente : nommée régente à deux reprises (en 1515 puis de 1524 à 1526), elle exerce une influence considérable sur le Conseil ; elle reçoit les ambassadeurs, négocie avec les princes et les princesses du temps, fait et défait des lignages et des carrières. Amatrice d’objets et d’œuvres d’art mais aussi bibliophile avertie, elle protège encore les artistes et les poètes, soutenant ainsi, voir suscitant, la création artistique et littéraire des quinze premières années du règne de François Ier. Si Louise de Savoie est l’une des personnalités les plus fascinantes de la première Modernité européenne, aucune monographie récente ne lui a été consacrée. Cet ouvrage rassemble un ensemble de textes, qui se proposent de traiter les aspects politiques, religieux et culturels de la vie de la mère de François Ier. Dans une première partie, les contributions abordent le parcours qui a mené la duchesse d’Angoulême de la Savoie à la cour de France. Un deuxième chapitre évoque Louise en tant que mère du roi et régente. La troisième section explicite le lien étroit que la comtesse et duchesse d’Angoulême a entretenu avec les arts. Enfin, l’enquête se conclue avec des études dédiées à l’intérêt de Louise pour les lettres. [less ▲]

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See detailModel-based computation of total stressed blood volume from a preload reduction manoeuvre
Pironet, Antoine ULg; Desaive, Thomas ULg; Chase, J. Geoffrey et al

in Mathematical Biosciences (2015), 265(0), 28-39

Total stressed blood volume is an important parameter for both doctors and engineers. From a medical point of view, it has been associated with the success or failure of fluid therapy, a primary treatment ... [more ▼]

Total stressed blood volume is an important parameter for both doctors and engineers. From a medical point of view, it has been associated with the success or failure of fluid therapy, a primary treatment to manage acute circulatory failure. From an engineering point of view, it dictates the cardiovascular system’s behavior in changing physiological situations. Current methods to determine this parameter involve repeated phases of circulatory arrests followed by fluid administration. In this work, a more straightforward method is developed using data from a preload reduction manoeuvre. A simple six-chamber cardiovascular system model is used and its parameters are adjusted to pig experimental data. The parameter adjustment process has three steps: (1) compute nominal values for all model parameters; (2) determine the five most sensitive parameters; and (3) adjust only these five parameters. Stressed blood volume was selected by the algorithm, which emphasizes the importance of this parameter. The model was able to track experimental trends with a maximal root mean squared error of 29.2%. Computed stressed blood volume equals 486 ± 117 ml or 15.7 ± 3.6 ml/kg, which matches previous independent experiments on pigs, dogs and humans. The method proposed in this work thus provides a simple way to compute total stressed blood volume from usual hemodynamic data. [less ▲]

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See detailComparison of experimental results and numerical modelling of unreinforced load-bearing masonry structures subjected to earthquake loading
Mordant, Christophe ULg; Denoël, Vincent ULg; Degée, Hervé

in Proceedings of the SECED 2015 Conference: Earthquake Risk and Engineering towards a Resilient World (2015, July)

This paper presents a comparison of experimental tests results on unreinforced load-bearing masonry structures subjected to earthquake loading with numerical predictions. First, simple walls are submitted ... [more ▼]

This paper presents a comparison of experimental tests results on unreinforced load-bearing masonry structures subjected to earthquake loading with numerical predictions. First, simple walls are submitted to cyclic and shaking table tests. Some of them include soundproofing devices in order to investigate their influence on the general behaviour in static and dynamic conditions. Additional walls with an opening and T-shaped walls are then tested under cyclic loading. The study is focused on the frame effect, the contribution of the perpendicular wall to the global strength and the efficiency of the connection. These aspects are also studied through shaking table tests on two masonry frames with T- or L-shaped piers. The main information is expressed in terms of force-displacement curves, mechanical properties and energy dissipation for the cyclic tests. The shaking table tests provide results in terms of dynamic and mechanical properties. Comparison of the results with numerical predictions is finally performed thanks to the software TREMURI. [less ▲]

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See detailSemi-empirical correlation to model heat losses along solar parabolic trough collectors
Dickes, Rémi ULg; Lemort, Vincent ULg; Quoilin, Sylvain ULg

Conference (2015, July)

Solar thermal power plants convert sunshine energy into useful heat and electricity by means of solar collectors and a thermodynamic cycle. Among the different solar collector technologies, parabolic ... [more ▼]

Solar thermal power plants convert sunshine energy into useful heat and electricity by means of solar collectors and a thermodynamic cycle. Among the different solar collector technologies, parabolic troughs are nowadays the most widespread together with solar towers. In order to improve the computation speed required to simulate the temperature profile along solar parabolic trough collectors, a correlation estimating the effective heat losses of the receiver is an essential tool. However, the relations found in the literature lack accuracy and do not translate effectively the effects of the operating conditions in all cases. In this work, an alternative correlation is proposed and calibrated with the results of a deterministic model. Better fitting performance is demonstrated when compared to the prediction of the pre-existing correlations. The benefits and limitations of the new correlation are finally assessed. [less ▲]

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See detailModel reduction for simulating the dynamic behavior of parabolic troughs and a thermocline energy storage in a micro-solar power unit
Dickes, Rémi ULg; Desideri, Adriano ULg; Lemort, Vincent ULg et al

Conference (2015, July)

Micro-scale concentrated solar power plants are characterized by strong transients and mostly operate in off-design working conditions. Both the sizing and the control of these systems are key challenges ... [more ▼]

Micro-scale concentrated solar power plants are characterized by strong transients and mostly operate in off-design working conditions. Both the sizing and the control of these systems are key challenges whose optimization requires powerful dynamic modeling tools. In this context, a system featuring a solar field of parabolic troughs, a thermocline thermal energy storage and a 5kWe organic Rankine cycle (ORC) power unit is modeled in the Modelica language. Model reduction methods applied to the solar field and the thermal storage are investigated and analyzed to improve the computational efficiency of the problem. Each model is described and integrated in the open-source ThermoCycle library. Results of simulation under identical operating conditions are compared and the benefits and limitations of model reduction are assessed. [less ▲]

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See detailAn XFEM/CZM implementation for massively parallel simulations of composites fracture
Vigueras, Guillermo; Sket, Federico; Samaniego, Cristobal et al

in Composite Structures (2015), 125

Because of their widely spread use in many industries, composites are the subject of many research campaigns. More particularly, the development of both accurate and flexible numerical models able to ... [more ▼]

Because of their widely spread use in many industries, composites are the subject of many research campaigns. More particularly, the development of both accurate and flexible numerical models able to capture their intrinsically multiscale modes of failure is still a challenge. The standard finite element method typically requires intensive remeshing to adequately capture the geometry of the cracks and high accuracy is thus often sacrificed in favor of scalability, and vice versa. In an effort to preserve both properties, we present here an extended finite element method (XFEM) for large scale composite fracture simulations. In this formulation, the standard FEM formulation is partially enriched by use of shifted Heaviside functions with special attention paid to the scalability of the scheme. This enrichment technique offers several benefits, since the interpolation property of the standard shape function still holds at the nodes. Those benefits include (i) no extra boundary condition for the enrichment degree of freedom, and (ii) no need for transition/blending regions; both of which contribute to maintain the scalability of the code. Two different cohesive zone models (CZM) are then adopted to capture the physics of the crack propagation mechanisms. At the intralaminar level, an extrinsic CZM embedded in the XFEM formulation is used. At the interlaminar level, an intrinsic CZM is adopted for predicting the failure. The overall framework is implemented in ALYA, a mechanics code specifically developed for large scale, massively parallel simulations of coupled multi-physics problems. The implementation of both intrinsic and extrinsic CZM models within the code is such that it conserves the extremely efficient scalability of ALYA while providing accurate physical simulations of computationally expensive phenomena. The strong scalability provided by the proposed implementation is demonstrated. The model is ultimately validated against a full experimental campaign of loading tests and X-ray tomography analyses for a chosen very large scale. [less ▲]

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See detailImpacts of climate change on future flood damage on the river Meuse, with a distributed uncertainty analysis
Detrembleur, Sylvain; Stilmant, Frédéric ULg; Dewals, Benjamin ULg et al

in Natural Hazards (2015), 77(3), 1533-1549

Flood-risk assessments are an objective and quantitative basis for implementing harmonized flood mitigation policies at the basin scale. However, the generated results are subject to different sources of ... [more ▼]

Flood-risk assessments are an objective and quantitative basis for implementing harmonized flood mitigation policies at the basin scale. However, the generated results are subject to different sources of uncertainty arising from underlying assumptions, data availability and the random nature of the phenomenon. These sources of uncertainty are likely to bias conclusions because they are irregularly distributed in space. Therefore, this paper addresses the question of the influence of local features on the expected annual damage in different municipalities. Based on results generated in the frame of a transnational flood-risk-assessment project for the river Meuse (Western Europe) taking climate change into account, the paper presents an analysis of the relative contributions of different sources of uncertainty within one single administrative region (the Walloon region in Belgium, i.e. a river reach of approximately 150 km). The main sources of uncertainty are not only found to vary both from one municipality to the other and in time, but also to induce opposite effects on the computed damage. Nevertheless, practical conclusions for policy-makers can still be drawn. [less ▲]

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See detailLong-term XMM-Newton investigation of two particle-accelerating colliding-wind binaries in NGC6604: HD168112 and HD167971
De Becker, Michaël ULg

in Monthly Notices of the Royal Astronomical Society (2015), 451(1), 5589-5599

The long-term (over more than one decade) X-ray emission from two massive stellar systems known to be particle accelerators is investigated using XMM-Newton. Their X-ray properties are interpreted taking ... [more ▼]

The long-term (over more than one decade) X-ray emission from two massive stellar systems known to be particle accelerators is investigated using XMM-Newton. Their X-ray properties are interpreted taking into account recent information about their multiplicity and orbital parameters. The two targets, HD168112 and HD167971 appear to be overluminous in X-rays, lending additional support to the idea that a significant contribution of the X-ray emission comes from colliding-wind regions. The variability of the X-ray flux from HD168112 is interpreted in terms of varying separation expected to follow the 1/D rule for adiabatic shocked winds. For HD167971, marginal decrease of the X-ray flux in September 2002 could tentatively be explained by a partial wind eclipse in the close pair. No long-term variability could be demonstrated despite the significant difference of separation between 2002 and 2014. This suggests the colliding-wind region in the wide orbit does not contribute a lot to the total X-ray emission, with a main contribution coming from the radiative shocked winds in the eclipsing pair. The later result provides evidence that shocks in a colliding-wind region may be efficient particle accelerators even in the absence of bright X-ray emission, suggesting particle acceleration may operate in a wide range of conditions. Finally, in hierarchical triple O-type systems, thermal X-rays do not necessarily constitute an efficient tracer to detect the wind-wind interaction in the long period orbit. [less ▲]

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See detailSelective top-down control of epiphytic biomass by amphipods from Posidonia oceanica meadows: implications for ecosystem functioning
Michel, Loïc ULg; Dauby, Patrick ULg; Dupont, Alessandra et al

in Belgian Journal of Zoology (2015), 145(2), 83-93

Mediterranean Posidonia oceanica meadows shelter an important biomass and biodiversity of amphipod crustaceans that graze on epiphytes. However, their actual significance for ecosystem functional ... [more ▼]

Mediterranean Posidonia oceanica meadows shelter an important biomass and biodiversity of amphipod crustaceans that graze on epiphytes. However, their actual significance for ecosystem functional processes is hard to estimate, due to the lack of adequate data. Here, a field microcosm-based inclusion experiment was used to test if three of the dominant taxa of the amphipod community (Apherusa chiereghinii, Dexamine spiniventris and Gammarus spp.) could exert top-down control on seagrass leaf epiphytes. Influence of amphipod activity on nutrient availability for the host species was also investigated. All grazer taxa significantly reduced biomasses of erect macroalgae and erect sessile animals present on leaves. None of them consumed encrusting epiflora or epifauna. This selective top-down control could have important implications for the structure of the epiphytic community of P. oceanica leaves, which is one of the most diverse and abundant of all seagrass species. Grazing activity of all taxa caused higher N content of seagrass leaves, likely through amphipod excretion and/or sloppy feeding. Since P. oceanica meadows often grow in oligotrophic zones where plant growth can be nutrient-limited, this N enrichment could enhance seagrass production. Overall, the ecological interaction between P. oceanica and amphipods could be seen as a facultative mutualistic relationship. Our results suggest that amphipod mesograzers are key-elements in some of the functional processes regulating these complex and yet endangered ecosystems, which are essential components of Mediterranean coastal zones. [less ▲]

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