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See detailAutonomous rigid body attitude synchronization
Sarlette, Alain ULg; Sepulchre, Rodolphe ULg; Leonard, Naomi

in Automatica (2009), 45(2), 572-577

Control laws to synchronize attitudes in a swarm of fully actuated rigid bodies, in the absence of a common reference attitude or hierarchy in the swarm, are proposed in [Smith, T. R., Hanssmann, H ... [more ▼]

Control laws to synchronize attitudes in a swarm of fully actuated rigid bodies, in the absence of a common reference attitude or hierarchy in the swarm, are proposed in [Smith, T. R., Hanssmann, H., & Leonard, N.E. (2001). "Orientation control of multiple underwater vehicles with symmetry-breaking potentials". In Proc. 40th IEEE conf. decision and control (pp. 4598–4603); Nair, S., Leonard, N. E. (2007). "Stable synchronization of rigid body networks". In Networks and Heterogeneous Media, 2(4), 595–624]. The present paper studies two separate extensions with the same energy shaping approach: (i) locally synchronizing the rigid bodies’ attitudes, but without restricting their final motion and (ii) relaxing the communication topology from undirected, fixed and connected to directed, varying and uniformly connected. The specific strategies that must be developed for these extensions illustrate the limitations of attitude control with reduced information. [less ▲]

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See detailL’étude ACCOMPLISH : remise en question des choix médicamenteux chez les patients hypertendus systoliques à haut risque cardio-vasculaire
Krzesinski, Jean-Marie ULg; Scheen, André ULg

in Revue Médicale de Liège (2009), 64(2), 103-108

Arterial hypertension is an important cardiovascular risk factor. The benefit drawn from decreasing and normalizing the blood pressure level is indisputable. The ACCOMPLISH study performed in patients ... [more ▼]

Arterial hypertension is an important cardiovascular risk factor. The benefit drawn from decreasing and normalizing the blood pressure level is indisputable. The ACCOMPLISH study performed in patients older than 65 with systolic hypertension and a high cardiovascular risk pointed out the interest of well choosing the antihypertensive combination to reduce this risk beyond the decrease of blood pressure. The association of benazepril (an angiotensin converting enzyme inhibitor or ACEI) and amlodipine (a calcium antagonist) has shown significant early cardiovascular protection in such patients as compared to the classic association including the same ACEI and hydrochlorothiazide, in spite of the same target blood pressure reached. This important finding does not contest the interest of a well controlled blood pressure in hypertension, but probably will modify our first antihypertensive combination choice in the future in patients with such cardiovascular profile. [less ▲]

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See detailFast Multi-Class Image Annotation with Random Subwindows and Multiple Output Randomized Trees
Dumont, Marie; Marée, Raphaël ULg; Wehenkel, Louis ULg et al

in Proc. International Conference on Computer Vision Theory and Applications (VISAPP) (2009, February)

This paper addresses image annotation, i.e. labelling pixels of an image with a class among a finite set of predefined classes. We propose a new method which extracts a sample of subwindows from a set of ... [more ▼]

This paper addresses image annotation, i.e. labelling pixels of an image with a class among a finite set of predefined classes. We propose a new method which extracts a sample of subwindows from a set of annotated images in order to train a subwindow annotation model by using the extremely randomized trees ensemble method appropriately extended to handle high-dimensional output spaces. The annotation of a pixel of an unseen image is done by aggregating the annotations of its subwindows containing this pixel. The proposed method is compared to a more basic approach predicting the class of a pixel from a single window centered on that pixel and to other state-of-the-art image annotation methods. In terms of accuracy, the proposed method significantly outperforms the basic method and shows good performances with respect to the state-of-the-art, while being more generic, conceptually simpler, and of higher computational efficiency than these latter. [less ▲]

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See detailOscillatority of Nonlinear Systems with Static Feedback
Efimov, Denis ULg; Fradkov, Alexander

in SIAM Journal on Control & Optimization (2009), 48(2), 618-640

New Lyapunov-like conditions for oscillatority of dynamical systems in the sense of Yakubovich are proposed. Unlike previous results these conditions are applicable to nonlinear systems and allow for ... [more ▼]

New Lyapunov-like conditions for oscillatority of dynamical systems in the sense of Yakubovich are proposed. Unlike previous results these conditions are applicable to nonlinear systems and allow for consideration of nonperiodic, e.g., chaotic modes. Upper and lower bounds for oscillations amplitude are obtained. The relation between the oscillatority bounds and excitability indices for the systems with the input are established. Control design procedure providing nonlinear systems with oscillatority property is proposed. Examples illustrating proposed results for Van der Pol system, Lorenz system, and Hindmarsh–Rose neuron model as well as computer simulation results are given. [less ▲]

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See detailPALETTE: Learning and Organisational Resources: Conceptual Instruments for Self- Analysis, Learning and Developments of CoPs
Ashwin, Paul; Daele, Amaury; Barlatier, Pierre-Jean et al

Report (2009)

The purpose of this deliverable is to present the researches that have been led for modelling learning and activities in CoPs. On the basis of these models, we developed Learning and Organisational ... [more ▼]

The purpose of this deliverable is to present the researches that have been led for modelling learning and activities in CoPs. On the basis of these models, we developed Learning and Organisational Resources (LORs) that are short activity scenarios aiming at developing learning, collaboration and uses of technological services in CoPs. The LORs are especially focused on the Generic Scenarios developed by WP5 and presented in D.IMP.08 i.e. ‘Reification’, ‘Debate & Decide’, and ‘Identity building’. The LORs have been trialled and evaluated by CoPs. In the conclusions, we synthesize the evaluation accounts from the CoPs and we provide advices for the use of the LORs by CoPs from various domains and contexts. [less ▲]

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See detailPredictors of Mortality after Endovascular Repair of the Thoracic Descending Aorta - The Preliminary New Zealand Experience.
Kolh, Philippe ULg

in European Journal of Vascular and Endovascular Surgery (2009), 37(2), 166-167

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See detailEchocardiography in the emergency roon: non-invasive imaging.
Pierard, Luc ULg; Lancellotti, Patrizio ULg

in Heart (2009), 95(2), 164

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See detailStress echocardiography expert consensus statement-executive summary: european association of echocardiography (a registrated branch of the ESC).
Sicari, R.; Nihoyannopoulos, P.; Evangelista, A. et al

in European Heart Journal (2009), 30(3), 278-89

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See detail2009 sera télescopique Le miroir liquide liégeois bientôt installé en Inde
Surdej, Jean ULg

Article for general public (2009)

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See detailDétection et estimation du niveau de la maladie rénale chronique
Delanaye, Pierre ULg; Cavalier, Etienne ULg; Mariat, Christophe et al

in Revue Médicale de Liège (2009), 64(2), 73-78

L’insuffisance rénale voit son incidence augmenter. Un diagnostic précoce et précis est requis. Le diagnostic de l’insuffisance rénale repose sur la mesure du débit de filtration glomérulaire. Les ... [more ▼]

L’insuffisance rénale voit son incidence augmenter. Un diagnostic précoce et précis est requis. Le diagnostic de l’insuffisance rénale repose sur la mesure du débit de filtration glomérulaire. Les formules basées sur la créatinine pour déterminer ce débit ont, par rapport à la créatinine sérique seule, apporté un plus mais, dans certaines situations, elles fournissent des résultats erronés. Le recours à la mesure de la clairance de créatinine sur une récolte d’urines de 24 heures peut être, dans ces situations où les caractéristiques anthropométriques sont hors normes, utile, mais avec toujours la difficulté d’une récolte minutée correcte. Si une mesure précise du débit de filtration glomérulaire est absolument nécessaire, une méthode de référence doit être choisie telle celle au chrome EDTA ou à l’iohexol. Enfin, tout bilan néphrologique doit, outre le dosage de créatinine, comprendre au moins une analyse d’urine à la tigette. Toute positivité pour la protéinurie lors de ce test mérite de réaliser un dosage quantitatif de la protéinurie soit sur 24 heures, soit plus aisément sur un échantillon [less ▲]

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See detailThe Beta Cephei star HD 180642: Full integration of CoRoT and ground data for mode identification
Briquet, Maryline ULg

Conference (2009, February)

The B1.5 II-III star HD 180642 is the only known Beta Cephei star in CoRoT’s core programme. To complement the space data of this target, both ground-based photometric and spectroscopic data were ... [more ▼]

The B1.5 II-III star HD 180642 is the only known Beta Cephei star in CoRoT’s core programme. To complement the space data of this target, both ground-based photometric and spectroscopic data were collected, to which we added several archival observations. In this talk, we describe our results from a full integration of CoRoT and intensive ground-based observations. The star is a non-linear dominant radial mode pulsator for which low-amplitude modes are detected for the fi rst time. A few of the latter are observed in our ground-based datasets so that a mode identifi cation for them is possible. To this end state-of-the-art techniques are adapted to be applied to a star with a highly non-linear behaviour of the radial mode. Additionally, a careful interpretation of the CoRoT lightcurve helps to identify the wavenumbers. Besides this outcome, the Van Hoof effect for the dominant mode is investigated and the stellar parameters and chemical abundances are determined. All this information is to be used as additional constraints to the CoRoT pulsation frequencies, for asteroseismic modelling of this Beta Cephei star. Additional abstracts cover the lightcurve modelling of this pulsator (Degroote et al.) as well as seismic modelling (Thoul et al.). [less ▲]

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See detailWhat Is The Role For Regulatory T-Cells After Nonmyeloablative Conditioning?
Humblet-Baron, S.; CASTERMANS, Emilie ULg; Vanbellinghen, J.-F. et al

in Biology of Blood & Marrow Transplantation (2009, February), 15(2), 122-123

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See detailAnalyse des relevés du réseau de vigies-odeur à Malvoisin.
Nicolas, Jacques ULg; Thomas, Jean-François

Report (2009)

The waste landfill area at Malvoisin was in the rehabilitation phase, involving various works, such as reshaping the waste mass. The research group decided to follow the evolution of the potential odour ... [more ▼]

The waste landfill area at Malvoisin was in the rehabilitation phase, involving various works, such as reshaping the waste mass. The research group decided to follow the evolution of the potential odour annoyance in the surroundings due to these works. A first survey in the surrounding population was followed by the setting up of a network of volunteers noting each day their personal feeling of the odour. The conclusion was that the odour was not excessive. [less ▲]

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See detailThe problem of a drillstring inside a curved borehole: a perturbed Eulerian approach
Denoël, Vincent ULg; Detournay, Emmanuel

(2009, February)

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See detailMicroarrays for allergy
Gadisseur, Romy ULg; Cavalier, Etienne ULg

Conference (2009, January 30)

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See detailContent-based Image Retrieval by Indexing Random Subwindows with Randomized Trees
Marée, Raphaël ULg; Geurts, Pierre ULg; Wehenkel, Louis ULg

in IPSJ Transactions on Computer Vision and Applications (2009), 1

We propose a new method for content-based image retrieval which exploits the similarity measure and indexing structure of totally randomized tree ensembles induced from a set of subwindows randomly ... [more ▼]

We propose a new method for content-based image retrieval which exploits the similarity measure and indexing structure of totally randomized tree ensembles induced from a set of subwindows randomly extracted from a sample of images. We also present the possibility of updating the model as new images come in, and the capability of comparing new images using a model previously constructed from a different set of images. The approach is quantitatively evaluated on various types of images and achieves high recognition rates despite its conceptual simplicity and computational efficiency. [less ▲]

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See detailGreenland ice sheet surface mass balance projections from IPCC AR4 global models
Franco, Bruno ULg; Fettweis, Xavier ULg; Erpicum, Michel ULg

Poster (2009, January 28)

Results from atmosphere-ocean general circulation models (AOGCM's) for the IPCC 4th Assessment Report are used to investigate surface mass balance (SMB) future projections of the Greenland ice sheet (GrIS ... [more ▼]

Results from atmosphere-ocean general circulation models (AOGCM's) for the IPCC 4th Assessment Report are used to investigate surface mass balance (SMB) future projections of the Greenland ice sheet (GrIS). The most efficient models for the GrIS climate modeling are chosen by comparison between the 1970-1999 outputs (averages and trends) from the Climate of the twentieth Century Experiment (20C3M) and reanalyses (ECMWF, NCEP) as well as observations (ice core measurements). The outputs from these most efficient models are after used to assess changes planned by the IPCC greenhouse gas emissions scenarios (SRES) for the 2070-2099 period. The GrIS SMB projections are estimated from changes in precipitation and temperatures from these AOGCM's outputs. However, large uncertainties remain in these SMB projections based on simplified physics and huge model outputs. High resolution simulations made with regional models (which simulate explicitly the SMB by taking into account the surface feedbacks) forced at their boundaries by a GrIS well-adapted AOGCM could bring more precise brief replies. [less ▲]

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See detailUse of C & N stable isotopes to evaluate interspecific trophic diversity among amphipods from Posidonia oceanica meadows
Michel, Loïc ULg; Lepoint, Gilles ULg; Nyssen, Fabienne ULg et al

Poster (2009, January 27)

Amphipods are one of the most diverse and abundant taxa of vagile invertebrates associated to Mediterranean Posidonia oceanica meadows. Therefore, they likely play an essential part in those ecosystems’ ... [more ▼]

Amphipods are one of the most diverse and abundant taxa of vagile invertebrates associated to Mediterranean Posidonia oceanica meadows. Therefore, they likely play an essential part in those ecosystems’ functioning, notably in organic matter transfers from producers to higher level consumers. Nevertheless, their trophic ecology remains poorly known, and they are generally regarded as epiflora grazers or generalist detritivores. Here, we focused on interspecific trophic diversity, and on the importance of other food sources (epifauna, Posidonia leaves & litter, suspended organic matter, …) in those amphipod’s diet. To achieve these goals, we used C and N stable isotopes ratios as trophic tracers. We noticed considerable trophic diversity among amphipods from different species, with δ13C values ranging from -16 to -26 ‰. Moreover, while some species (such as Apherusa chiereghinii and Aora spinicornis) seem to feed mainly on epiphytes, others, like Dexamine spiniventris, exploit other food sources. This study enhances the comprehension of the feeding ecology of these amphipods, and therefore of the way they interact with the Posidonia meadow ecosystem. [less ▲]

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See detailTowards a comprehensive C-budgeting approach of a coccolithophorid bloom in the Northern Bay of Biscay (June 2006)
Harlay, Jérôme ULg; Borges, Alberto ULg; De Bodt, Caroline et al

Poster (2009, January 25)

A biogeochemical multidisciplinary survey was carried out in the northern Bay of Biscay, in early June 2006, during which 14C-based primary production and calcification were determined as well as O2-based ... [more ▼]

A biogeochemical multidisciplinary survey was carried out in the northern Bay of Biscay, in early June 2006, during which 14C-based primary production and calcification were determined as well as O2-based community respiration. Contemporary remote sensing images showed several patches of high reflectance (HR) in the investigated area. Based on remote sensing and in situ measured biogeochemical parameters, the area exhibited varying coccolithophorid bloom stages from its early development to the post-bloom stages. The major HR patch, characterizing a post-stationary stage of the bloom, was located between 48°N and 49°N over the shelf along the continental margin. It was associated with moderate chlorophyll-a levels, never exceeding 1.0 µg L-1, dissolved phosphorus and silica depletion, and undersaturation of CO2 with respect to atmospheric equilibrium. Considered as the main drivers of the C cycle in this area, the CO2 fluxes associated with primary production, calcification and respiration were integrated in order to provide a comprehensive C budget in the area. [less ▲]

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