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See detailSensitivity in shape optimization of complex 3D geometries using level sets and non-conforming finite elements
Duysinx, Pierre ULg; Van Miegroet, Laurent ULg

Conference (2009, September)

For the last 20 years shape optimization has been stocking to penetrate industrial and real-life applications, whereas topology optimization was experiencing a fast growing soar and extensions to various ... [more ▼]

For the last 20 years shape optimization has been stocking to penetrate industrial and real-life applications, whereas topology optimization was experiencing a fast growing soar and extensions to various applications. By the way there is still a great interest in shape optimization because of the intrinsic capability of shape description to facilitate considering complex problems involving local stress and manufacturing constraints for instance. The level set description proposed by Osher and Sethian (1988) opened new perspectives to handle variable boundaries as in shape optimization. The implicit description of the geometrical entities allows for a more friendly and flexible manipulation of the geometry and overcome some restrictions related to the explicit approach of the geometry used in CAD systems: for example it is possible to reduce the topological complexity by removing or merging geometric entities (i.e. holes can merge or disappear) without degenerating the model, which was major restriction of shape optimization. A few years ago, the level set method was nicely complemented by the XFEM (eXtended Finite Element Method) proposed by Moes et al (1999). This approach greatly reduces the difficulty of considering time-variable boundaries and complex geometries by using non-conforming meshes. This is definitively an advantage to circumvent the so-called velocity field to carry out shape sensitivity and mesh relocation difficulties, especially with thin walled structures or 3D designs. The present research is continuing along and extending works by Duysinx et al (2006) and Van Miegroet and Duysinx (2007) to consider shape optimization based on a parametric level set description and XFEM. The work that is carried out in a common research project EFCONICO sponsored by the Walloon Region of Belgium aims at extending preliminary results 3 D structure and complex geometries, increasing the reliability of the method, enhancing the performances using advanced mesh generators as Gmsh, etc. In particular the paper presents new theoretical developments and their numerical implementation in sensitivity analysis with respect to parametric design variable of level sets. The developments are illustrated with numerical applications dealing with complex shape applications involving 3D geometries and the boundary conditions along design variable boundaries. [less ▲]

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See detailSevikar° ou Forzaten° : combinaison fixe olmésartan médoxomil-amlodipine bésylate dans le traitement de l'hypertension artérielle
Krzesinski, Jean-Marie ULg; Scheen, André ULg

in Revue Médicale de Liège (2009), 64(9), 468-473

The interest for powerful and better tolerated antihypertensive combinations is searched in the field of hypertension, because of a too large number of people still not well controlled. The recent ... [more ▼]

The interest for powerful and better tolerated antihypertensive combinations is searched in the field of hypertension, because of a too large number of people still not well controlled. The recent association between an angiotensin receptor blocker, olmesartan, and a long-acting dihydropyridine, amlodipine, reinforces our therapeutic possibilities. The synergistic effect of the two molecules potentiate the antihypertensive activity, which allows improving the quality and the rapidity of the blood pressure control. Furthermore, the fixed combination should improve patient’s compliance. The contra-indications still remain those of the sartan family. The most frequent side-effect of amlodipine monotherapy, oedema, occurs in a much lower proportion with the addition of olmesartan. [less ▲]

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See detailControl strategies study of a complete solar assisted air conditioning system in an office building using TRNSYS
Thomas, Sébastien ULg; Andre, Philippe ULg

(2009, September)

It is now clearly assumed that solar assisted air conditioning is able to minimize environmental impact and CO2 production of buildings operation. How to reach highest energy savings is still a work in ... [more ▼]

It is now clearly assumed that solar assisted air conditioning is able to minimize environmental impact and CO2 production of buildings operation. How to reach highest energy savings is still a work in progress. In former literature, equipment control has been point out as a critical feature of energy consumption. Control becomes more and more important as system is complex. The complete simulation environment was developed in previous work, it includes the absorption chiller itself, the rejection circuit (cooling tower), solar panels field, heater, storage device, pumps, heating-cooling networks, emission system and building. TRNSYS software modular approach provides the possibility to model and simulate this complete system. In this article, different strategies are proposed to minimize consumption for air-conditioning. [less ▲]

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See detailLe rôle du Fonds des Maladies Professionnelles en faveur de la réadaptation des patients lombalgiques
Poot, Olivier; Strauss, Patrick; Mairiaux, Philippe ULg

in Revue Médicale de Bruxelles (2009), 30(4), 326-329

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See detailEtude socio-écologique appliquée à la gestion de la plaisance dans une aire marine protégée: Cas de l’AMP Tavolara-Punta Coda Cavallo.
Perez Perera, Amanda ULg

Master's dissertation (2009)

Les rivages les plus beaux de Méditerranée sont particulièrement attractifs pour les plaisanciers. Dans les AMP, la forte concentration de la navigation et des mouillages dans des sites esthétiques et ... [more ▼]

Les rivages les plus beaux de Méditerranée sont particulièrement attractifs pour les plaisanciers. Dans les AMP, la forte concentration de la navigation et des mouillages dans des sites esthétiques et abrités constituent un problème majeur pour la gestion de l’aire au niveau social et économique, mais aussi pour la dégradation des écosystèmes marins, tel que les herbiers à P. oceanica. L’objectif principal de ce mémoire est de fournir des recommandations pour la plaisance, en particulier celle des ancrages, dans l’AMP de Tavolara-Punta Coda Cavallo. Ainsi trois approches on été utilisées. Une approche de sociologie qualitative qui consiste à décrire la relation qui lie la protection du milieu naturel et le développement de la plaisance. En suite, une approche de sociologie quantitative qui tente de caractériser les types d’embarcation utilisé dans l’AMP, de déterminer quelle sont les perceptions des plaisanciers sur l’AMP et les herbiers de Posidonies et les habitudes et les motivations des plaisanciers sur la navigation. Enfin, nous avons réalisé une comparaison des caractéristiques structurelles d’un herbier entre une zone potentiellement peu impacté (zone contrôle) et une zone soumise à l’ancrage (zone d’ancrage) afin de disposer des informations écologiques sur l’état actuel de l’herbier dans les zones de mouillage. [less ▲]

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See detailLong-term glycaemic effects of pioglitazone compared with placebo as add-on treatment to metformin or sulphonylurea monotherapy in PROactive (PROactive 18)
Scheen, André ULg; Tan, M. H.; Betteridge, D. J. et al

in Diabetic Medicine : A Journal of the British Diabetic Association (2009)

Abstract Aims To assess the long-term glycaemic effects, concomitant changes in medications, and initiation of permanent insulin use (defined as daily insulin use for a period of ≥90 days, or ongoing use ... [more ▼]

Abstract Aims To assess the long-term glycaemic effects, concomitant changes in medications, and initiation of permanent insulin use (defined as daily insulin use for a period of ≥90 days, or ongoing use at death/final visit) with pioglitazone vs. placebo in diabetic patients receiving metformin or sulphonylurea monotherapy at baseline in the PROspective pioglitAzone Clinical Trial in macroVascular Events (PROactive). Methods In PROactive, patients with Type 2 diabetes and macrovascular disease were randomized to pioglitazone (force-titrated to 45 mg/day) or placebo, in addition to other existing glucose-lowering therapies. In a post-hoc analysis, we categorized patients not receiving insulin at baseline and treated by oral monotherapy into two main cohorts: addon to metformin alone (n = 514) and sulphonylurea alone (n = 1001). The follow-up averaged 34.5 months. Results There were significantly greater reductions in glycated haemoglobin (HbA1c) with pioglitazone than with placebo and more pioglitazone-treated patients achieved HbA1c targets, irrespective of the baseline oral glucose-lowering regimen and despite a decrease in the use of other glucose-lowering agents. Approximately twice as many in the placebo groups progressed to permanent insulin use than in the pioglitazone groups across the two cohorts: 3.4% for pioglitazone and 6.5% for placebo when added to metformin monotherapy and 6.3% and 14.8%, respectively, when added to sulphonylurea monotherapy. The overall safety of both dual therapies was good. Conclusions Intensifying an existing oral monotherapy regimen to a dual oral regimen by adding pioglitazone resulted in sustained improvements in glycaemic control and reduced progression to insulin therapy. The efficacy and safety of adding pioglitazone to either metformin monotherapy or sulphonylurea monotherapy were good. [less ▲]

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See detailA proof of concept of Iterative DSM improvement through SAR scene simulation
De Rauw, Dominique ULg

in ISPRS Journal of Photogrammetry & Remote Sensing (2009), XXXVIII(3/W4), 121-126

In Very High Resolution (VHR) Synthesis Aperture Radar (SAR) context, very fine and accurate georeferencing and geoprojection processes are required. Both operations are only applicable if accurate local ... [more ▼]

In Very High Resolution (VHR) Synthesis Aperture Radar (SAR) context, very fine and accurate georeferencing and geoprojection processes are required. Both operations are only applicable if accurate local heights are known. 3D information may be derived from SAR interferometry (InSAR), But in VHR context, InSAR reveals to be inaccurate mostly due to phase unwrapping problems and to phase/height noise. Generated InSAR Digital Surface Models (DSM) can only be considered as a first good approximation of the observed surface. Therefore, we proposed to start from the InSAR DSM, to project it on ground range on a given datum, to model the observed scene using this projected DSM, then to simulate in slant range the intensity image issued from this structure model. Comparison between simulated and observed intensity image can then be used as a criterion to modify and improve the considered underlying DSM. In this paper, we present the different steps of the proposed approach and results obtained so far, showing that the proposed process can be run iteratively to modify the DSM and reach a stable solution. [less ▲]

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See detailBP reduction, organ protection and CV risk : what's new?
Krzesinski, Jean-Marie ULg

in Journal de Cardiologie [= JDC] = Tijdschrift voor Cardiologie [= TVC] (2009), 21(5), 257-262

Résumé et commentaires à propos d’un symposium satellite organisé lors du 19 ème congrès de l’European Society of Hypertension tenu à Milan en juin 2009. L’HTA est un facteur majeur de risque ... [more ▼]

Résumé et commentaires à propos d’un symposium satellite organisé lors du 19 ème congrès de l’European Society of Hypertension tenu à Milan en juin 2009. L’HTA est un facteur majeur de risque cardiovasculaire. Sa détection doit être validée. Une fois définie, il faut évaluer le risque cardiovasculaire de l’hypertendu. Le contrôle de l’hypertension artérielle mérite une meilleure attention et plus d’initiatives de la part du médecin. Le traitement passe par une approche multifactorielle où les règles hygiénodiététiques sont capitales. Si nécessaire, il faut ajouter des médicaments en choisissant ceux qui sont efficaces et bien tolérés pour un traitement au long cours. Les associations ‘bloqueurs du système rénine-angiotensine et antagoniste calcique’ constituent une nouvelle approche efficace et métaboliquement plus favorable que celles où les diurétiques sont associés à ces bloqueurs de l’axe rénineangiotensine. L’association énalapril – lercanidipine offre des perspectives fort intéressantes notamment dans le haut risque cardiovasculaire pour une efficacité et une adhérence au traitement excellentes. [less ▲]

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See detailCrystal Plasticity Modelling of Monotonic Shear Tests on Pure Titanium
Hammami, Walid ULg; Bouvier, S.; Duchene, Laurent ULg et al

in Oñate, E.; Owen, D. R. J. (Eds.) Computational plasticity X. Fundamentals and applications (2009, September)

This study consists in the modelling of shear tests performed on pure titanium using a polycrystalline model. Numerical and experimental results are presented.

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See detailNumerical Modeling of Representative Cells of Ti-5553 Using Periodic Homogenization Technique
Gerday, Anne-Françoise ULg; Ben Bettaieb, Mohamed ULg; Pascon, Frédéric ULg et al

in Oñate, E.; Owen, D. R. J. (Eds.) Computational plasticity X. Fundamentals and applications (2009, September)

This article focuses on the modeling of representative cells of Ti-5553 using the periodic homogenization theory and a microscopic constitutive law.

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See detailThe Role of Void Evolution on the bendability of Steel Sheets
Ben Bettaieb, Mohamed ULg; Lemoine, Xavier; Duchene, Laurent ULg et al

in Oñate, E.; Owen, D. R. J. (Eds.) Computational plasticity X. Fundamentals and applications (2009, September)

In the present contribution, an advanced Gurson model is developed and implemented in the Lagamine finite element code[1. This model is used to simulate the bending process and to predict the bendability ... [more ▼]

In the present contribution, an advanced Gurson model is developed and implemented in the Lagamine finite element code[1. This model is used to simulate the bending process and to predict the bendability of the studied sheet. [less ▲]

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See detailSWAps in motion: Lessons from case studies in six African countries
Paul, Elisabeth ULg; Laokri, Samia; Robert, Annie

in Tropical Medicine & International Health [=TM & IH] (2009), 14(Supplement 2), 18

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See detailcarnet de pédiatrie en Afrique: notes de pédiatrie comportementale
Battisti, Oreste ULg

Learning material (2009)

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See detailLes politologues dans le débat public
Jacquemain, Marc ULg

Conference (2009, September)

The paper shows how political analysts not only have the right to participate in public debates but also have a duty to do so. It also examines what are the conditions of separation between expert ... [more ▼]

The paper shows how political analysts not only have the right to participate in public debates but also have a duty to do so. It also examines what are the conditions of separation between expert attitude and commitment so that this freedom of speech does not degenerate into propaganda. [less ▲]

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See detailRecovery of γ-decalactone produced by Rhodotorula aurantiaca from the culture broth using Macronet resins
Alchihab, Mohamed; Aldric, Jean-Marc ULg; Aguedo, Mario ULg et al

in New Biotechnology (2009, September), 25S

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