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See detailUncertainty quantification of Antarctic contribution to sea-level rise using the fast Elementary Thermomechanical Ice Sheet (f.ETISh) model
Bulthuis, Kevin ULg; Arnst, Maarten ULg; Pattyn, Frank et al

Conference (2017, April)

Uncertainties in sea-level rise projections are mostly due to uncertainties in Antarctic ice-sheet predictions (IPCC AR5 report, 2013), because key parameters related to the current state of the Antarctic ... [more ▼]

Uncertainties in sea-level rise projections are mostly due to uncertainties in Antarctic ice-sheet predictions (IPCC AR5 report, 2013), because key parameters related to the current state of the Antarctic ice sheet (e.g. sub-ice- shelf melting) and future climate forcing are poorly constrained. Here, we propose to improve the predictions of Antarctic ice-sheet behaviour using new uncertainty quantification methods. As opposed to ensemble modelling (Bindschadler et al., 2013) which provides a rather limited view on input and output dispersion, new stochastic methods (Le Maître and Knio, 2010) can provide deeper insight into the impact of uncertainties on complex system behaviour. Such stochastic methods usually begin with deducing a probabilistic description of input parameter uncertainties from the available data. Then, the impact of these input parameter uncertainties on output quantities is assessed by estimating the probability distribution of the outputs by means of uncertainty propagation methods such as Monte Carlo methods or stochastic expansion methods. The use of such uncertainty propagation methods in glaciology may be computationally costly because of the high computational complexity of ice-sheet models. This challenge emphasises the importance of developing reliable and computationally efficient ice-sheet models such as the f.ETISh ice-sheet model (Pattyn, 2015), a new fast thermomechanical coupled ice sheet/ice shelf model capable of handling complex and critical processes such as the marine ice-sheet instability mechanism. Here, we apply these methods to investigate the role of uncertainties in sub-ice-shelf melting, calving rates and climate projections in assessing Antarctic contribution to sea-level rise for the next centuries using the f.ETISh model. We detail the methods and show results that provide nominal values and uncertainty bounds for future sea- level rise as a reflection of the impact of the input parameter uncertainties under consideration, as well as a ranking of the input parameter uncertainties in the order of the significance of their contribution to uncertainty in future sea-level rise. In addition, we discuss how limitations posed by the available information (poorly constrained data) pose challenges that motivate our current research. [less ▲]

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See detailBien raisonner en TSUM (Transition Secondaire-Université en Mathématiques)
Bair, Jacques ULg

E-print/Working paper (2017)

Bien raisonner est assurément une des compétences clés que doivent acquérir et développer les étudiants entrant à l’Université. Nous y consacrons entièrement ce travail illustré par de nombreux exemples ... [more ▼]

Bien raisonner est assurément une des compétences clés que doivent acquérir et développer les étudiants entrant à l’Université. Nous y consacrons entièrement ce travail illustré par de nombreux exemples construits à partir de notre expérience professionnelle. En premier lieu, nous distinguons, à la suite de G. Polya, les raisonnements plausibles des raisonnements démonstratifs. Ensuite, nous nous intéressons à certains éléments de logique qui nous paraissent importants au niveau d’une TSUM. Puis, nous analysons la nature de preuves mathématiques à ce stade de l’apprentissage. Enfin, nous dissertons quelque peu sur l’usage des démonstrations dans l’enseignement. Ce travail se termine par deux annexes techniques, relatives respectivement à différents types de syllogismes et à quelques éléments plus formels de logique mathématique. [less ▲]

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See detailSystematic flood modelling to support flood-proof urban design
Bruwier, Martin ULg; Mustafa, Ahmed; Aliaga, Daniel et al

Conference (2017, April)

Urban flood risk is influenced by many factors such as hydro-meteorological drivers, existing drainage systems as well as vulnerability of population and assets. The urban fabric itself has also a complex ... [more ▼]

Urban flood risk is influenced by many factors such as hydro-meteorological drivers, existing drainage systems as well as vulnerability of population and assets. The urban fabric itself has also a complex influence on inundation flows. In this research, we performed a systematic analysis on how various characteristics of urban patterns control inundation flow within the urban area and upstream of it. An urban generator tool was used to generate over 2,250 synthetic urban networks of 1 km². This tool is based on the procedural modelling presented by Parish and Müller (2001) which was adapted to generate a broader variety of urban networks. Nine input parameters were used to control the urban geometry. Three of them define the average length, orientation and curvature of the streets. Two orthogonal major roads, for which the width constitutes the fourth input parameter, work as constraints to generate the urban network. The width of secondary streets is given by the fifth input parameter. Each parcel generated by the street network based on a parcel mean area parameter can be either a park or a building parcel depending on the park ratio parameter. Three setback parameters constraint the exact location of the building whithin a building parcel. For each of synthetic urban network, detailed two-dimensional inundation maps were computed with a hydraulic model. The computational efficiency was enhanced by means of a porosity model. This enables the use of a coarser computational grid , while preserving information on the detailed geometry of the urban network (Sanders et al. 2008). These porosity parameters reflect not only the void fraction, which influences the storage capacity of the urban area, but also the influence of buildings on flow conveyance (dynamic effects). A sensitivity analysis was performed based on the inundation maps to highlight the respective impact of each input parameter characteristizing the urban networks. The findings of the study pinpoint which properties of urban networks have a major influence on urban inundation flow, enabling better informed flood-proof urban design. [less ▲]

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See detailMicrofossils from the late Mesoproterozoic – early Neoproterozoic Atar/El Mreïti Group, Taoudeni Basin, Mauritania, northwestern Africa
Beghin, Jérémie ULg; Storme, Jean-Yves; Blanpied, Christian et al

in Precambrian Research (2017), 291

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See detailUsefulness of multi-breed models in genetic evaluation of direct and maternal calving ease in Holstein and Belgian Blue Walloon purebreds and crossbreds
Vanderick, Sylvie ULg; Gillon, Alain; Glorieux, Géry et al

in Livestock Science (2017), 198

The objective of this study was to verify the feasibility of a joint genetic evaluation system for calving ease trait of Belgian Blue (BBB) and Holstein (HOL) Walloon cattle based on data of purebred and ... [more ▼]

The objective of this study was to verify the feasibility of a joint genetic evaluation system for calving ease trait of Belgian Blue (BBB) and Holstein (HOL) Walloon cattle based on data of purebred and crossbred animals. Variance components and derived genetic parameters for purebred BBB and HOL animals were estimated by using single-breed linear animal models. This analysis showed clear genetic differences between breeds. Estimates of direct and maternal heritabilities (± standard error) were 0.34 (±0.02) and 0.09 (±0.01) for BBB, respectively, but only 0.09 (±0.01) and 0.04 (±0.01) for HOL, respectively. Moreover, a significant negative genetic correlation between direct and maternal effects was obtained in both breeds: −0.46 (±0.04) for BBB and −0.29 (±0.11) for HOL. Variance components and derived genetic parameters for purebred BBB and HOL and crossbred BBB ×× HOL cattle were then estimated by using two multi-breed linear animal models: a multi-breed model based on a random regression test-day model (Model MBV), and a multi-breed model based on the random regression multi-breed model (Model MBSM). Both multi-breed models use different functions of breed proportions as random regressions, thereby enabling modelling different additive effects according to animal's breed composition. The main difference between these models is the way in which relationships between breeds are accounted for in the genetic (co)variance structure. Genetic parameters differed between single-breed and multi-breed analysis, but are similar to the literature. For BBB, estimates of direct and maternal heritabilities (±SE) were 0.45 (±0.07) and 0.08 (±0.01) by using Model MBV, and 0.45 (±0.08) and 0.09 (±0.02) for Model MBSM, respectively. For HOL, these estimates were 0.18 (±0.04) and 0.05 (±0.01) using Model MBV, and 0.16 (±0.04) and 0.05 (±0.01) for Model MBSM, respectively. Reliability gains (up to 25%) indicated that the use of crossbred data in the multi-breed models had a positive influence on the estimation of genetic merit of purebred animals. A slight re-ranking of purebred sires and maternal grandsires was observed between single-breed and multi-breed models. Moreover, both multi-breed models can be considered as quasi-equivalent models because they performed almost equally well with respect to MSE and correlations, for purebred and crossbred animals. [less ▲]

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See detailBaelo dans l'Antiquité tardive. L'occupation du secteur sud-est du forum entre les IIIe et VIe s.
Brassous, Laurent; Deru, Xavier ULg; Rodriguez, Oliva et al

in Melanges de la Casa de Velazquez (2017), 47(1),

Les recherches archéologiques conduites au sud-est du forum de la ville romaine de Baelo claudia ont permis de mettre au jour au-dessus du secteur monumental, plusieurs phases de transformation, d’abandon ... [more ▼]

Les recherches archéologiques conduites au sud-est du forum de la ville romaine de Baelo claudia ont permis de mettre au jour au-dessus du secteur monumental, plusieurs phases de transformation, d’abandon et de réoccupation entre les IIIe et VIe s. Les structures découvertes ainsi que le nombreux mobilier qui leur était associé (monnaies, céramique, verre, métal, faune, etc.) fournissent un éclairage nouveau sur l’histoire et la nature de l’agglomération dans l’antiquité tardive, qui entre la fin du IVe s. et son abandon définitif au VIe s. ressemble moins à une ville qu’à un gros village. [less ▲]

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See detailIntroduction to Nonlinear Aeroelasticity
Dimitriadis, Grigorios ULg

Book published by Wiley (2017)

Nonlinear aeroelasticity has become an increasingly popular research area over the last 20-30 years. There have been many driving forces behind this development, including faster computers, increasingly ... [more ▼]

Nonlinear aeroelasticity has become an increasingly popular research area over the last 20-30 years. There have been many driving forces behind this development, including faster computers, increasingly flexible structures, automatic control systems for aircraft and other engineering products, new materials with nonlinear characteristics etc. Introduction to Nonlinear Aeroelasticity covers the theoretical basics in nonlinear aeroelasticity and applies the theory to practical problems. As nonlinear aeroelasticity is a combined topic, necessitating expertise from different areas, this book also covers areas such as nonlinear dynamics, bifurcation analysis, numerical methods and others. The emphasis throughout is on the practical application of the theories and methods, so as to enable the reader to apply their newly acquired knowledge [less ▲]

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See detailLes Q-Codes et la terminologie multilingue de médecine générale et de famille
Jamoulle, Marc ULg; Schuers, Matthieu; Ouvrard, Patrick et al

Conference (2017, March 31)

voir pdf

Detailed reference viewed: 114 (2 ULg)
See detailStaatssteun aan groene energie
Van Cleynenbreugel, Pieter ULg

Scientific conference (2017, March 31)

In this presentation, I tackle the subject of aid in the context of green energy, discussing the legal framework as well as cases and pitfalls.

Detailed reference viewed: 16 (0 ULg)
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See detailDevelopment of Mass Spectrometry based Analytical Tools for Animal Venoms Characterization
Echterbille, Julien ULg

Doctoral thesis (2017)

Animal venoms and toxins are now recognized as major sources of bioactive molecules that may be tomorrow’s new drug leads. Their complexity and their potential as drug sources have been demonstrated by ... [more ▼]

Animal venoms and toxins are now recognized as major sources of bioactive molecules that may be tomorrow’s new drug leads. Their complexity and their potential as drug sources have been demonstrated by application of modern analytical technologies, which have revealed venoms to be vast peptide combinatorial libraries. Structural as well as pharmacological diversity is immense, and mass spectrometry is now one of the major investigative tools for the structural investigation of venom components. The present work is dedicated to the development of new mass spectrometry-based methodologies for the study of animal venoms. The first methodology depicts an original approach to sequence snake toxins in a higher throughput way after an orthogonal separation of the crude venom. The second analytical development is devoted to decipher disulfide connectivity in cone snails’ toxins through a combination of partial reduction/oxidation followed by ion mobility separation of the semi-reduced/oxidized species and CID fragmentation. The last part of this work is focused on the capture of ligands of nAChRs in complex mixtures of peptides, especially in cone snail venoms. A new ligand has been discovered and fully characterized. [less ▲]

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See detailResearch in Prison from the inside. An uncomfortable position for the "Official-Researcher"?
Sevenants, Yves ULg

Conference (2017, March 28)

Presentation about the experience of a native researcher in prison.

Detailed reference viewed: 19 (1 ULg)
See detailL'interdiction du port du voile au travail
Kéfer, Fabienne ULg

Scientific conference (2017, March 28)

Séminaire faisant suite aux arrêts de la CJUE du 17 mars 2017 (C.J.U.E., 14 mars 2017, G4S Secure Solutions, C-157/15 ; C.J.U.E., 14 mars 2017, Micropole Univers, C-188/15)

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See detailFrom Loose to Boxed Fragments and Back Again. Seriality and Archive in Chris Ware's ‘Building Stories’
Crucifix, Benoît ULg

in Journal of Graphic Novels and Comics (2017)

This article focuses on the dynamics of seriality, archive and collection in Chris Ware's graphic novel “Building Stories”. It argues that the dispersed serialization of “Building Stories” is key to ... [more ▼]

This article focuses on the dynamics of seriality, archive and collection in Chris Ware's graphic novel “Building Stories”. It argues that the dispersed serialization of “Building Stories” is key to understand its box-of- comics format as well as its fragmented narrative structure. In a self-reflexive homage to the material history of comics, Ware's graphic novel indeed appears as an archive of its own serialization, foregrounding a process of collecting/dispersing fragments. [less ▲]

Detailed reference viewed: 31 (15 ULg)