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See detailX-ray microtomography: A porosity-based thresholding method to improve soil pore network characterization?
Beckers, Eléonore ULg; Plougonven, Erwan ULg; Roisin, Christian et al

in Geoderma (2014), 219-220

X-ray microtomography, through quantification of soil structure at the microscale, could greatly facilitate the current understanding of soil hydrodynamic behaviour. However, binarisation method and ... [more ▼]

X-ray microtomography, through quantification of soil structure at the microscale, could greatly facilitate the current understanding of soil hydrodynamic behaviour. However, binarisation method and processing choices are subjective and can have a strong impact on results and conclusions. In this study, we test a new method based on the porosity detectable by X-ray microtomography, while validation is achieved through comparison of soil microtomogram information with soil physical measurements. These measurements consist of water retention and unsaturated hydraulic conductivity using two different soil populations with only structural differences. To assess the porosity-based method performances, we compare it to four other methods, namely the global method of Otsu and three recent soil-dedicated local methods. The robustness of the porosity-based method is also tested in regard to different pre-processing procedures. In this paper we demonstrate that soil segmentation through a porosity-based method is an interesting issue. Indeed, it is less demanding in terms of time and computational requirements than its alternatives, and combines robustness and performances broadly comparable with the recent local methods. [less ▲]

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See detailDesign of a reliable processing pipeline for the non-intrusive measurement of feet trajectories with lasers
Pierard, Sébastien ULg; Azrour, Samir ULg; Van Droogenbroeck, Marc ULg

in International Conference on Acoustics, Speech, and Signal Processing (ICASSP) (2014, May)

Reliable measurements of feet trajectories are needed in some applications, such as biomedical applications. This paper describes the data processing pipeline used in GAIMS, which is a non-intrusive ... [more ▼]

Reliable measurements of feet trajectories are needed in some applications, such as biomedical applications. This paper describes the data processing pipeline used in GAIMS, which is a non-intrusive system that measures feet trajectories based on multiple range laser scanners. Our processing pipeline relies on a new tracking paradigm, and it is based on two innovative algorithms: the first algorithm localizes the feet directly from the observed point cloud without any clustering, and the other algorithm identifies the feet. After reviewing the various types of noise affecting the point cloud, this paper explains the limitations of the classical processing approach and gives an overview of our new pipeline. The effectiveness of the proposed approach is established by discussing the results that have been obtained in several studies based on GAIMS. [less ▲]

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See detail« La flexicurité : une politique des idées ? Regards croisés d’acteurs institutionnels belges en 2013 »
Beuker, Laura ULg; Gérard, Julie ULg; Orianne, Jean-François ULg

Conference (2014, May)

Cette communication porte sur la traduction, en Belgique, d’une politique européenne de l’emploi – la flexicurité – par différents acteurs institutionnels. À partir d’une analyse documentaire et d’une ... [more ▼]

Cette communication porte sur la traduction, en Belgique, d’une politique européenne de l’emploi – la flexicurité – par différents acteurs institutionnels. À partir d’une analyse documentaire et d’une vingtaine d’entretiens semi-directifs, nous étudierons la manière dont ces acteurs s’approprient et interprètent la flexicurité. Nous nous appuierons principalement sur les apports récents de la sociologie de l’action publique, en particulier l’approche cognitive des politiques publiques (Surel, 2000 ; Muller et Surel, 1998) et l’européanisation des politiques d’emploi (Palier et Surel, 2007 ; 2010). Nous montrerons que cette appropriation a donné lieu, en Belgique, à une transformation de sens conféré à la sécurité, celle-ci étant dorénavant substitué à celui de la flexibilité. [less ▲]

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See detailAnalysis of transient scattering problems using a discontinuous Galerkin method: application to the shielding effectiveness of enclosures with heterogeneous walls
Boubekeur, Mohamed; Kameni, Abelin; Pichon, Lionel et al

in International Journal of Numerical Modelling: Electronic Networks, Devices and Fields (2014), 27(3), 626-635

In this paper, different formulations of Maxwell equations are combined for computing the shielding effectiveness of enclosures made from heterogeneous periodic materials. The validity of the homogenized ... [more ▼]

In this paper, different formulations of Maxwell equations are combined for computing the shielding effectiveness of enclosures made from heterogeneous periodic materials. The validity of the homogenized parameters given by Maxwell-Garnett rules in the frequency domain are tested in the time domain using a nodal discontinuous Galerkin method, which uses an interface condition based on analytical solution in the frequency domain to replace a conductive sheet. This interface condition allows to avoid meshing the thin sheet, thus reducing the computational cost. Results of scattering by composite enclosures are presented in the frequency domain thanks to a Fast Fourier Transform. [less ▲]

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See detailEntre recettes du Soi et recettes de l'Autre. Ethnographie de pratiques culinaires marocaines à Sesto San Giovanni (Milan, Italie)
Mescoli, Elsa ULg

Doctoral thesis (2014)

La thèse porte sur les processus de subjectivation d’un groupe de femmes marocaines résidant dans la ville de Sesto San Giovanni, dans le nord de l’Italie. Elsa Mescoli considère les habitudes ... [more ▼]

La thèse porte sur les processus de subjectivation d’un groupe de femmes marocaines résidant dans la ville de Sesto San Giovanni, dans le nord de l’Italie. Elsa Mescoli considère les habitudes alimentaires et les pratiques culinaires de ces femmes et de leurs familles, facteurs qui agissent dans la construction de soi à plusieurs niveau : celui intime, en contexte domestique ; celui partagé/contesté, en contexte publique. L’étude se situe au croisement entre l’anthropologie de l’alimentation, l’anthropologie de la culture matérielle et l’anthropologie des migrations. En fait, ces processus sont analysés en adoptant une perspective praxéologique, c’est-à-dire en portant l’attention sur la matérialité. La thèse met en évidence les « ingrédients » concrets de la définition de soi des femmes considérées, ainsi que de leurs rapports interpersonnels et « interculturels ». [less ▲]

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See detailMultiscale modelling of angiogenesis during normal and impaired bone regeneration
Carlier, Aurélie ULg

Doctoral thesis (2014)

Bone regeneration is, like many other healing events, a complex, well-orchestrated process involving a myriad of different cell types and regulated by countless biochemical, physical and mechanical ... [more ▼]

Bone regeneration is, like many other healing events, a complex, well-orchestrated process involving a myriad of different cell types and regulated by countless biochemical, physical and mechanical factors. But unlike other adult biological tissues, the majority of bone fractures can heal without the production of scar tissue, eventually recovering the original bone shape, size and strength. Despite bone’s remarkable healing capacity and the continuing research efforts, the impaired healing of complex orthopaedic cases is still not fully understood. This PhD work hypothesises that computational modelling can make a substantial contribution to the bone regeneration field by proposing and testing the underlying mechanisms of action as well as by designing and optimising experimental strategies in silico. In the first part of this work, an existing bioregulatory model of fracture healing is extended with an intracellular module of Dll4-Notch1 signalling in order to capture the ingrowth of new blood vessels through sprouting angiogenesis. The predictions of the new MOSAIC model are compared to experimental results and an extensive sensitivity analysis is performed on the newly introduced parameters. The potential of the MOSAIC model to investigate the influence of the molecular mechanisms on angiogenesis and consequently the bone formation process is illustrated. In the second part of this work, the MOSAIC model is further improved with a rigorous implementation of the influence of oxygen on the behaviour of skeletal cells. A comprehensive literature study is performed in order to ensure the correspondence of the oxygen ranges of the cell-specific oxygen-dependent processes with the state-of-the-art experimental knowledge. The oxygen model is corroborated with previously published experimental results. The robustness of the oxygen model with respect to the newly introduced oxygen thresholds is demonstrated by a sensitivity analysis. Some limitations and shortcomings of the oxygen model are identified together with suggestions for future work. In the last part of this work, the added value of the oxygen model is shown by applying it to three cases of impaired bone healing: the occurrence of nonunions in critical size defects, bone graft healing in a compromised environment and the impaired healing of bone fractures in NF1 patients. Not only is the oxygen model used to determine the underlying mechanisms of action, potential treatment strategies for the respective challenging orthopaedic conditions are also designed and optimised in silico. In conclusion, this PhD thesis demonstrates the potential of an integrative in vivo-in silico approach to advance our current understanding of bone regeneration as well as to design effective treatments of complex bone fractures. [less ▲]

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See detailControl of attosecond electronic dynamics in molecules
Mignolet, Benoît ULg

Doctoral thesis (2014)

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See detailDioxin Analyses. The Dogs Bark, but the Caravan Goes on...
Focant, Jean-François ULg

Scientific conference (2014, April 28)

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See detailMicrofossils’ diversity from the Proterozoic Taoudeni Basin, Mauritania
Beghin, Jérémie ULg; Javaux, Emmanuelle ULg; Houzay, Jean-Pierre et al

in European Geosciences Union General Assembly 2014 Vienna, Austria, 27 April – 02 May 2014 (abstract book) (2014, April 27)

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See detailIntroduction aux travaux de Luciano Del Pistoia : corps et psychose
Englebert, Jérôme ULg

Scientific conference (2014, April 25)

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See detailNanostructured catalysts by sol-gel process
Lambert, Stéphanie ULg; Heinrichs, Benoît ULg

Conference (2014, April 25)

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See detailPredicting Grain Protein Content of Winter Wheat
Mansouri, Majdi ULg; Dumont, Benjamin ULg; Destain, Marie-France ULg

in ESANN 2014 Proceedings (2014, April 24)

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See detailA Frequency-domain Approach to Subspace Identification of Nonlinear Systems, Application to Aerospace Structures
Noël, Jean-Philippe ULg

Doctoral thesis (2014)

The construction of mathematical models from experimental data is an essential step in the design process of engineering systems. The different tasks involved in this activity, from the measurement and ... [more ▼]

The construction of mathematical models from experimental data is an essential step in the design process of engineering systems. The different tasks involved in this activity, from the measurement and processing of data to the validation of the model, fall into the general field of system identification. In structural dynamics, the theoretical and experimental aspects of linear system identification have been successfully addressed since the early seventies, and mature analytical, computational and testing tools have emerged. Nonlinear system identification of vibrating structures has also enjoyed significant advances during the past few years. However, the common practice in industry is to ignore nonlinearities, arguably because their analysis is still regarded as impractical. The objective of this doctoral thesis is precisely to progress towards the development of a practical system identification methodology dedicated to real-life nonlinear structures. The first facet of the thesis is to introduce a nonlinear generalisation in the frequency domain of the so-called subspace identification methods. The proposed frequency-domain nonlinear subspace identification (FNSI) approach yields accurate models of large-scale systems comprising strong nonlinearities, closely-spaced modes and high damping. Because it can also estimate a large number of parameters while maintaining an acceptable computational burden, the second facet of this research is to investigate the utilisation of cubic splines as a very flexible means to model complex nonlinearities. Finally, the third facet of the present work is to derive nonlinear models with optimal statistical properties in the presence of measurement noise. This is achieved by embedding the FNSI method into the maximum likelihood identification framework. The scope of the identification and modelling tools developed in this thesis encompasses nonlinear structural systems originating from the various areas of vibration engineering, including the aerospace, mechanical or civil fields, amongst others. Throughout the dissertation, these tools are illustrated using numerical and experimental structures of increasing complexity, mainly related to aerospace applications. [less ▲]

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See detailMachine learning techniques to assess the performance of a gait analysis system
Pierard, Sébastien ULg; Phan-Ba, Rémy; Van Droogenbroeck, Marc ULg

Poster (2014, April 24)

This paper presents a methodology based on machine learning techniques to assess the performance of a system measuring the trajectories of the lower limbs extremities for the follow-up of patients with ... [more ▼]

This paper presents a methodology based on machine learning techniques to assess the performance of a system measuring the trajectories of the lower limbs extremities for the follow-up of patients with multiple sclerosis. We show how we have established, with the help of machine learning, four important properties about this system: (1) an automated analysis of gait characteristics provides an improved analysis with respect to that of a human expert, (2) after learning, the gait characteristics provided by this system are valuable compared to measures taken by stopwatches, as used in the standardized tests, (3) the motion of the lower limbs extremities contains a lot of useful information about the gait, even if it is only a small part of the body motion, (4) a measurement system combined with a machine learning tool is sensitive to intra-subject modifications of the walking pattern. [less ▲]

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See detailLe psychopathe : apprésentation, chosification de l’alter ego et compétences émotionnelles
Englebert, Jérôme ULg

Conference (2014, April 23)

La psychopathie est une entité diagnostique « trouble », tant au sein de la tradition psychopathologique que dans les nosographies internationales contemporaines (DSM-IV et DSM-V). Le modèle faisant ... [more ▼]

La psychopathie est une entité diagnostique « trouble », tant au sein de la tradition psychopathologique que dans les nosographies internationales contemporaines (DSM-IV et DSM-V). Le modèle faisant autorité en psychologie forensic est celui développé par R.D. Hare (2003) à travers une échelle diagnostique appelée PCL-R. Ce modèle rencontre, d’un point de vue théorique, plusieurs apories, et, d’un point de vue clinique, de nombreuses impasses. Nous proposons de réaliser un exercice de compréhension psychopathologique axé sur notre pratique clinique en nous inspirant des recommandations du courant de la psychopathologie phénoménologique (Minkowski, 1966 ; Binswanger, 1960 ; Stanghellini, 2006 ; Sass, Parnas & Zahavi, 2011). Celui-ci suggère de procéder par la mise en évidence de la structure psychopathologique qui organise le fonctionnement psychologique du sujet. De façon plus précise, nous centrerons notre propos sur deux dimensions essentielles à l’être-au-monde psychopathique. D’une part, nous réaliserons une comparaison avec l’être-au-monde maniaque à travers les variables de l’apprésentation et de la chosification de l’alter ego – telles que les développe Binswanger (1960). Nous discuterons, d’autre part, du vécu émotionnel propre à la psychopathie qui est davantage source d’adaptation (du moins en certaines situations) que de carence véritable. Ce constat nous permettra de rediscuter brièvement de la notion d’empathie en psychopathologie. Nous verrons que ces dimensions propres à l’existence psychopathique font apparaitre une thématique explicitement absente de la nosographie de Hare, celle de la morale. [less ▲]

Detailed reference viewed: 31 (1 ULg)