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See detailAnalysis versus synthesis for trending of gas-path measurement time series
Borguet, Sébastien ULg; Léonard, Olivier ULg; Dewallef, Pierre ULg

in Proceedings of ASME Turbo Expo 2014 (2014, June)

Gas-path measurements used to assess the health condition of an engine are corrupted by noise. Generally, a data cleaning step occurs before proceeding with fault detection and isolation. Classical linear ... [more ▼]

Gas-path measurements used to assess the health condition of an engine are corrupted by noise. Generally, a data cleaning step occurs before proceeding with fault detection and isolation. Classical linear filters such as the exponentially weighted moving average filter are traditionally used for noise removal. Unfortunately, these low-pass filters distort trend shifts indicative of faults, which increases the detection delay. The present paper investigates two new approaches to non-linear filtering of time series. On one hand, the synthesis approach reconstructs the signal as a combination of elementary signals chosen from a pre-defined library. On the other hand, the analysis approach imposes a constraint on the shape of the signal (e.g., piecewise constant). Both approaches incorporate prior information about the signal in a different way, but they lead to trend filters that are very capable at noise removal while preserving at the same time sharp edges in the signal. This is highlighted through the comparison with a classical linear filter on a batch of synthetic data representative of typical engine fault profiles. [less ▲]

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See detailÉtude des changements de circulation au-dessus de l'océan Austral en été
Belleflamme, Alexandre ULg; Fettweis, Xavier ULg; Erpicum, Michel ULg

in Camberlin, Pierre; Richard, Yves (Eds.) Actes du XXVIIème colloque de l'Association de Climatologie - Climat : système & interactions (2014, June)

Over the five last decades, the reanalyses (ERA and NCEP/NCAR) show a strengthening of the pressure gradient between the southern hemisphere subtropical anticyclone belt and the southern circumpolar lows ... [more ▼]

Over the five last decades, the reanalyses (ERA and NCEP/NCAR) show a strengthening of the pressure gradient between the southern hemisphere subtropical anticyclone belt and the southern circumpolar lows during summer. With the help of an automatic circulation type classification, we show that the strengthening of the pressure gradient is generalised to all circulation types and, paradoxically, it does not cause circulation changes. It is probably implied by the strengthening of the temperature gradient between the tropics and the South Pole, without consequences on the general circulation. Our classification also allows a successful comparison between the two reanalyses in a region where the observation data are rare. [less ▲]

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See detailLe "péril jaune" en RDC : mythe ou réalité ?
Wintgens, Sophie ULg; Kabamba, Bob ULg

in Santander, Sébastian (Ed.) L’Afrique, nouveau terrain de jeu des émergents (2014)

L’influence de la Chine en république démocratique du Congo (RDC) se caractérise par son caractère tardif mais fulgurant, au regard d’une présence chinoise historiquement forte en Afrique subsaharienne ... [more ▼]

L’influence de la Chine en république démocratique du Congo (RDC) se caractérise par son caractère tardif mais fulgurant, au regard d’une présence chinoise historiquement forte en Afrique subsaharienne. Son implantation offensive en RDC résulte d’une convergence d’intérêts entre un État chinois en quête de matières premières et de terres arables pour assurer son développement économique et sa stabilité politique, et un État congolais en (re)construction résolument acquis, depuis l’élection du président Joseph Kabila, au modèle de développement chinois fondé sur la séparation volontaire entre objectifs économiques et réformes politiques (prêts inconditionnés, aide déliée). En consacrant l’accroissement rapide des relations commerciales sino-congolaises, le partenariat stratégique Chine-Afrique, scellé en 2006 lors du troisième Forum de coopération sino-africain, participe plus largement de la remise en cause du rôle des puissances traditionnellement influentes dans la région. Au-delà de la concurrence économique induite vis-à-vis des États-Unis, du Japon et des institutions financières internationales au sein desquelles elle est largement représentée, l’Europe assiste plus singulièrement à la remise en question de son leadership régional et à la dépréciation normative de sa politique développementale. Entre émancipation et hégémonie, cet article vise à mettre au jour les enjeux stratégiques inhérents à l’impact du "facteur chinois" en RDC. [less ▲]

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See detailPlatelet-rich plasma to treat patellar tendinopathies: a 1 year follow-up.
Kaux, Jean-François ULg; Croisier, Jean-Louis ULg; Bruyère, Olivier ULg et al

in Clinical Chemistry & Laboratory Medicine (2014, June), 52(Special Suppl), 1285

Background: Jumper’s knee is a frequent chronic overuse syndrome of the upper part of the patellar tendon. Platelets contain lots of growth factors which could enhance the healing process of tendons ... [more ▼]

Background: Jumper’s knee is a frequent chronic overuse syndrome of the upper part of the patellar tendon. Platelets contain lots of growth factors which could enhance the healing process of tendons. Infiltration of Platelet Rich Plasma (PRP) may be considered as a recent therapeutic option for chronic tendinopathies. The aim of the current study is to evaluate the clinical status and the return to sports activities in patients with chronic upper patellar tendinopathies up to 1 year after 1 infiltration of PRP. Methods: Twenty patients with chronic upper patellar tendinopathy were enrolled. Assessments were made before infiltration of PRP, and 6 weeks and 3 months and 1 year after the infiltration, using a 10-point Visual Analogic Scale and algofunctional scores (IKDC and VISA-P). Moreover, they had to answer an information questionnaire concerning their life and sports activities. The PRP was obtained with an apheresis system (COM.TEC, Fresenius). Six millilitres of PRP were injected without local anaesthetic. One week after infiltration, patients started a standardised sub-maximal eccentric reeducation. Results: Pain during daily activities significantly decreased with time. VAS has significantly dropped, IKDC and VISA-P significantly improved over the follow-up of 1 year. Seventy percents of patients reported a favourable evolution with decrease of pain, 15% did never report any improvement and 15% were treated surgically. Seventy percents returned to sports activities, 64,3% without any pain, and 50% of them recovered the same sport level. Younger patients seemed to be more susceptible to have an improvement of pain by the PRP infiltration. Conclusions: This study demonstrates that a local infiltration of PRP associated with a submaximal eccentric protocol can improve, at 1 year, symptoms of chronic jumper’s knee in patients non-responsive to classical conservative treatments. [less ▲]

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See detailDoes the achievement of an intermediate glycemic target reduce organ failure and mortality? A post-hoc analysis of the Glucontrol Trial
Penning, Sophie ULg; Chase, J. Geoffrey; Preiser, Jean-Charles et al

in Journal of Critical Care (2014)

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See detailInhibition of PDH Kinase as a new therapeutic target for Age-related Macular Degeneration (AMD)
Arslan, Deniz ULg; Pirotte, Bernard ULg; De Tullio, Pascal ULg et al

Poster (2014, June)

Metabolomics is one of the most recent technologies in the world of Omics sciences. It aims at studying metabolome, which is composed of small molecular weight organic molecules (called metabolites) of a ... [more ▼]

Metabolomics is one of the most recent technologies in the world of Omics sciences. It aims at studying metabolome, which is composed of small molecular weight organic molecules (called metabolites) of a cell, an organism or a biological system. This approach gives rise to a growing number of applications in many areas, such as biomarkers discovery, clinical studies, drug efficacy and toxicity evaluation, diagnostic tools, quality control. One of the most interesting features of metabolomics is its capability to extract biochemical information reflecting biological events and then to be a powerful tool in the knowledge of the aetiology of some pathologies. Indeed, it is clear that every disease could alter more or less drastically the metabolic profile of the patients. Then a metabolomics approach could highlight the biochemical pathways affected and could allow the identification of new putative therapeutic strategies or targets that could be useful in a new drug discovery strategy. As proteomics, metabolomics approach represents a new and powerful tool for Medicinal Chemistry. Age-related Macular Degeneration (AMD) is a leading cause of vision loss in the western world among people aged 50 or older. 90% of all vision loss due to AMD results from the exudative form, which is characterized by choroidal neovascularization (CNV). Age-related changes that induce pathologic CNV are incompletely understood. A successful application of anti-VEGF approaches in the clinic is obviously a turning point in AMD treatment. Nevertheless, despite such important advances, critical issues remain to be addressed. To better understand the aetiology of this pathology, we used and improved a murine model of laser-induced choroidal neovascularization and applied a 1H NMR metabolomics study. This approach leads to the emergence of different putative biomarkers and to the validation of the CNV model for an experimental study of AMD. Among these “biomarkers”, lactate appears to be clearly involved in the development of AMD. The modulation of their plasma concentration by treatment of the animals with synthetic compounds and more specifically Pyruvate DesHydrogenase Kinase inhibitors (PDHK) significantly decrease the impact of laser induced CNV. Starting from these results, the development of new PDHK inhibitors could open the way to innovative treatment opportunities in AMD disease. [less ▲]

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See detailSocial Security and Economic Integration
Artige, Lionel ULg; Dedry, Antoine ULg; Pestieau, Pierre ULg

in Economics Letters (2014), 123(June), 318-322

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See detailThe Call for project proposals « Let’s live my village »: between free interpretations and compulsory readings regarding innovation and convivial village ambiance in Wallonia.
Schmitz, Serge ULg

in Les campagnes: espaces d'innovation dans un monde urbain (2014, June)

The paper scrutinizes 186 rural development projects selected on the short list of the first and second “Lets’ live my village!” calls. It examines trends concerning rural community life and the identity ... [more ▼]

The paper scrutinizes 186 rural development projects selected on the short list of the first and second “Lets’ live my village!” calls. It examines trends concerning rural community life and the identity of the leaders/brokers. It pays attention to the way that associations define rurality. Question 14 of the application form « Does your association act in rural areas? Explain” is the main source of information for content analysis and contingency tables [less ▲]

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See detailPhysical controls on the storage of methane in landfast sea ice
Zhou, Jiayun ULg; Tison, J.-L.; Carnat, G. et al

in The Cryosphere (2014), 8(3), 1019-1029

We report on methane (CH4) dynamics in landfast sea ice, brine and under-ice seawater at Barrow in 2009. The CH4 concentrations in under-ice water ranged between 25.9 and 116.4 nmol L-1sw, indicating a ... [more ▼]

We report on methane (CH4) dynamics in landfast sea ice, brine and under-ice seawater at Barrow in 2009. The CH4 concentrations in under-ice water ranged between 25.9 and 116.4 nmol L-1sw, indicating a supersaturation of 700 to 3100 % relative to the atmosphere. In comparison, the CH4 concentrations in sea ice, ranged between 3.4 and 17.2 nmol L-1ice, and the deduced CH4 concentrations in brine, between 13.2 and 677.7 nmol L-1brine. We investigated on the processes explaining the difference in CH4 concentrations between sea ice, brine and the under-ice water, and suggest that biological controls on the storage of CH4 in ice was minor in comparison to the physical controls. Two physical processes regulated the storage of CH4 in our landfast ice samples: bubble formation within the ice and sea ice permeability. Gas bubble formation from solubility changes had favoured the accumulation of CH4 in the ice at the beginning of ice growth. CH4 retention in sea ice was then twice as efficient as that of salt; this also explains the overall higher CH4 concentrations in brine than in the under-ice water. As sea ice thickened, gas bubble formation became less efficient, CH4 was then mainly trapped in the dissolved state. The increase of sea ice permeability during ice melt marked the end of CH4 storage. [less ▲]

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See detailCHARACTERIZATION OF PROTEINURIA IN DOGUE DE BORDEAUX DOGS USING ELECTROPHORESIS AND URINARY BIOMARKERS
Lavoué, Rachel; Smets, P.; Trumel, Cathy et al

in Proceedings of the 2014 ACVIM Forum (2014, June)

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See detailL’effet d’un dispositif public d’accompagnement et de formation belge sur les trajectoires professionnelles des demandeurs d’emploi
Gérard, Julie ULg

Conference (2014, June)

: Suite aux récents bouleversements économiques et sociaux touchant les pays de l’Union Européenne, de nombreux partenariats entre services publics d’emploi et agences d’emploi privées se sont développés ... [more ▼]

: Suite aux récents bouleversements économiques et sociaux touchant les pays de l’Union Européenne, de nombreux partenariats entre services publics d’emploi et agences d’emploi privées se sont développés et complexifiés, suivant une logique de gestion mixte du marché de l’emploi. Cette communication porte sur l’étude d’un partenariat public-privé entre un service public régional belge et un organisme de formation. À partir des apports conceptuels et théoriques de la sociologie de l’action publique et de la littérature propre aux agences d’emploi privées et aux partenariats public-privé, nous analyserons la capacité d’un dispositif public à assurer la remise à l’emploi de son public-cible. Pour ce faire, nous étudierons son rôle et ses effets sur les trajectoires professionnelles des demandeurs d’emploi y recourant. [less ▲]

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See detailL’effet des dispositifs d’intermédiation sur les trajectoires professionnelles des travailleurs. Le cas d’un bureau de recrutement, recherche et sélection de personnel.
Gérard, Julie ULg

Conference (2014, June)

Au cours de ces dernières années, le souci d’allier flexibilité et sécurité au travail a conduit à l’essor considérable des métiers de l’intermédiation (Orianne et Maroy, 2008). En particulier dans le ... [more ▼]

Au cours de ces dernières années, le souci d’allier flexibilité et sécurité au travail a conduit à l’essor considérable des métiers de l’intermédiation (Orianne et Maroy, 2008). En particulier dans le domaine de l’accompagnement et du développement de carrière, divers dispositifs privés d’aide et de suivi ont vu le jour afin de contribuer à l’amélioration des conditions de travail et d’assister les travailleurs dans leurs transitions professionnelles. Par leur action, ces nouveaux dispositifs n’hésitent pas à complexifier les temporalités sociales en créant de nouvelles opportunités d’emploi et en redéfinissant les rythmes de carrière. À l’aide d’une étude de cas dans le secteur du recrutement belge, nous analyserons la capacité d’un processus de mise en emploi à remplir de tels objectifs dans un contexte de gestion mixte du marché du travail. Approchée d’une manière qualitative (entretiens semi-directifs et observations), nous étudierons l’apport de cette agence de placement au travers d’un cadre théorique qui intègre les concepts de dispositif (Foucault, 1977 ; Peeters et Charlier, 1999 ; Raffnsoe, 2008) et de réseaux sociaux (Grossetti 2005, 2008 et 2011). Nous montrerons qu’un plus de régir l’offre et la demande de travail, ce dispositif d’intermédiation, par son système de cooptation et son accompagnement de carrière, assure la fluidification du marché et sécurise la dynamique des transitions professionnelles. [less ▲]

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See detailExtension patterns in pituitary macroadenomas and relation to T2-weightd signal on diagnostic MRI examinations
Potorac, I; Cattin, F; KREUTZ, Julie ULg et al

Poster (2014, June)

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See detailLaTeX, un peu, beaucoup (4. Les "équations" et leurs styles)
Dupont, Pascal ULg

in Losanges (2014)

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See detailGCxGC-HRTOFMS a Powerful Tool in Separation Science
Focant, Jean-François ULg

Scientific conference (2014, June)

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See detailUsing intensive multiyear fish-pass monitoring to analyse seasonal upstream movement patterns of patrimonial holobiotic potomadromous fish species in a medium size river
Benitez, Jean-Philippe ULg; Nzau Matondo, Billy ULg; Dierckx, Arnaud ULg et al

in Proceedings of the 10th International Conference on Ecohydraulics (2014, June)

Belgian rivers are fragmented by numerous obstacles which considerably limit the free access of fish to functional habitats. Fish-passes are major tools used to increase stream continuity and improve ... [more ▼]

Belgian rivers are fragmented by numerous obstacles which considerably limit the free access of fish to functional habitats. Fish-passes are major tools used to increase stream continuity and improve connectivity in the upstream direction. Using two modern multispecies fish-passes, this study aims to investigate multiyear abundance of holobiotic potamodromous fish and their seasonal movement patterns in relation with environmental factors. The fish passes were monitored continuously during 5 and 7 years and are located in two Belgian streams: the (19.3m³.s-1) and the Berwinne (1.9m³.s-1). Results revealed the presence of 20 different fish species, 14 species in the Berwinne and 19 species in the occurrence, salmonids and cyprinids species were predominant. A great interspecific and intraspecific variability in capture periodicity and in terms of stimulation by combination of factor environmental was observed. This study highlights the complexity and the omnipresence of holobiotic potamodromous fish movements at different life stages, in medium size river and brings new information on fish passes efficiency and use by these poorly known species. [less ▲]

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See detailThe cyclic behaviour of sand, from the Prevost model to offshore geotechnics
Cerfontaine, Benjamin ULg

Doctoral thesis (2014)

The main objective of this thesis is the studying of the cyclic behaviour of dense sand. Its centre of gravity is the implementation of a convenient constitutive law in the finite element code LAGAMINE ... [more ▼]

The main objective of this thesis is the studying of the cyclic behaviour of dense sand. Its centre of gravity is the implementation of a convenient constitutive law in the finite element code LAGAMINE. The first step consists in summarising the salient features of the cyclic behaviour of sand observed in laboratory tests. Undrained monotonic and cyclic experiments are addressed. The phase transformation line is a key parameter in the description of its behaviour. The plasticity effects in both loading and unloading, the progressive pore pressure accumulation coupled with the degradation of the stiffness of the soil are of uttermost importance in the cyclic behaviour. The Prevost model is adopted for its conceptual simplicity and its physically related parameters. The basic equations of the model are described and its variants are illustrated. Calibration of the required parameters is carried out by means of simplified routines implemented in Matlab. A unique set of parameters is determined for each soil at a given relative density. Monotonic experiments are well reproduced. The model also replicates satisfactorily the trend of cyclic experiments. An implicit scheme is embraced in order to implement the model in the finite element code LAGAMINE. The implicit Prager translation rule is adopted for that purpose. It is ensured the discrete formulation reproduces exactly the analytical model. Accuracy, efficiency and robustness of the model are addressed throughout triaxial and multi-axial numerical examples. A hydro-mechanical interface finite element is developed. It consists in a three-node 1D isoparametric element. It is able to reproduce fluid flows across and along the interface. The unsticking of both walls of the interface is coupled with a suction effect due to the filling of the vacuum created. The behaviour of the element is illustrated by simple 1D examples of transient consolidation of a soil column. A final application consists in the modelling of a suction caisson, part of a tripod structure for wind turbines. An axisymmetric representation of this foundation is carried out. It is assumed embedded into dense Lund sand described by the Prevost model. Monotonic and cyclic simulations are performed in both drained and partially drained conditions. The salient features of the resistance of such foundations are highlighted. Their partially drained behaviour strongly increases their transient resistance. A storm including an extreme event is employed to simulate a cyclic loading. A pseudo-random short signal and its sinusoidal equivalent representation finally lead to an identical vertical settlement. This is confirmed by a long duration storm. Finally, a cyclic diagram summarising the final settlement attained for combinations of average and cyclic vertical loads is elaborated. Keywords [less ▲]

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