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See detailGrey-box identification of a non-linear solar array structure using cubic splines
Noël, Jean-Philippe ULg; Kerschen, Gaëtan ULg; Foltête, Emmanuel et al

in International Journal of Non-Linear Mechanics (2014), 67

Most identification methods in non-linear structural dynamics assume in advance a mathematical model of the non-linearities. This is however possible in specific situations only, since non-linear effects ... [more ▼]

Most identification methods in non-linear structural dynamics assume in advance a mathematical model of the non-linearities. This is however possible in specific situations only, since non-linear effects may be caused by numerous phenomena and a priori knowledge is generally limited. The present paper investigates the usefulness of piecewise third-order polynomials, termed cubic splines, to identify the complex non-linear dynamics of solar arrays in their stowed configuration. The estimation of the model parameters is achieved using the frequency-domain non-linear subspace identification (FNSI) method. A distinct advantage of the FNSI approach is its capability to calculate accurately a large number of parameters, while maintaining an acceptable computational burden. This makes tractable the use of cubic splines to represent non-linearity in real-life mechanical systems, as the dimensionality of the inverse problem is known to increase dramatically in this case. The experimental structure of interest consists of two parallel aluminium plates assembled with bolted connections. This application is challenging because of the existence of impacts between the two plates at high excitation amplitude, and of the activation of complicated stiffness and damping mechanisms within the bolted connections. [less ▲]

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See detailConclusion
Famerie, Etienne ULg

in La diplomatie romaine sous la République : réflexions sur une pratique (2014)

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See detailWood digestion in lower termites: multidisciplinary approaches based on differential feeding
Bauwens, Julien ULg; Brasseur, Catherine ULg; Tarayre, Cédric ULg et al

Poster (2014, December)

Termites digestive tract and hindgut especially still holds many secrets despites hundreds of years of research. The complexity of the symbiotic microbial community and the contrast of physio-chemical ... [more ▼]

Termites digestive tract and hindgut especially still holds many secrets despites hundreds of years of research. The complexity of the symbiotic microbial community and the contrast of physio-chemical environments found in lower termites paunch are potentially the key point to explain the efficiency of ligno-cellulose digestion. Contribution of advancing technologies accelerates the progress of our knowledge in this field. Here, we present multiple approaches combining old and recent techniques used to highlight the effect of ligno-cellulosic compounds on termite gut and the role of populations from the symbiotic microbial community. Termites Reticulitermes flavipes (Kollar) submitted to various artificial diets showed variations in flagellates populations profile and enzymatic activities. Differential protein expression was investigated using 2D-DIGE MALDI-TOF-TOF and 2D-LC-MS/MS using high resolution orbitrap analyzer. Results from both proteomic experiments tend to support each-other and bring complementary points of view. The gel-free analysis resulted in highly contrasted identification of enzymes involved in ligno-cellulose digestion and metabolism. Finally, differential feeding experiments leaded to in vivo selection of different symbiotic communities. These communities were characterized following some metabolism assays and allowed the cultivation of diverse microbial consortia using media closely related to the respective artificial diets. This work provides relevant data on termite and associated microbial community response to alimentary diets. [less ▲]

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See detailA finite-element reciprocity solution for EEG forward modeling with realistic individual head models
Ziegler, Erik ULg; Chellappa, Sarah Laxhmi ULg; Gaggioni, Giulia ULg et al

in NeuroImage (2014), 103

Highlights • Creates EEG forward models suitable for high-resolution source localization. • Automatic T1-based whole-head finite element meshing and leadfield computation. • Pipelines can incorporate ... [more ▼]

Highlights • Creates EEG forward models suitable for high-resolution source localization. • Automatic T1-based whole-head finite element meshing and leadfield computation. • Pipelines can incorporate conductivity tensors from diffusion-weighted images. • Open-source toolbox shared under a permissive software license. • Accuracy comparable to SimBio FEM and superior to OpenMEEG BEM solutions. [less ▲]

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See detailExperimental validation of a thermal model of a LOx flooded ball bearing
Servais, Christophe ULg; Bozet, Jean-Luc ULg; Kreit, Patrick ULg et al

in Tribology International (2014), 80

Ball bearings of turbopumps of rocket engines work in very singular conditions; they are flooded into liquid oxygen or liquid hydrogen. Therefore, the use of any conventional lubricants (oil or grease) is ... [more ▼]

Ball bearings of turbopumps of rocket engines work in very singular conditions; they are flooded into liquid oxygen or liquid hydrogen. Therefore, the use of any conventional lubricants (oil or grease) is prescribed. Although cryogenic fluids can cool this kind of ball bearing, they cannot separate the surfaces in contact. As a result, there is a significant increase in frictional power losses. This paper presents tests performed on a cryotechnic ball bearing flooded in liquid oxygen. The test results showed that beyond a critical loading of the bearing, a sudden increase in temperature occurred. A thermal model is also put forward, in order to understand and anticipate especially the thermal instability described above. [less ▲]

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See detailInput of supercritical carbon dioxide to polymer synthesis: an overview
Boyère, Cédric; Jérôme, Christine ULg; Debuigne, Antoine ULg

in European Polymer Journal (2014), 61

The ongoing search for environmentally friendlier alternative to the organic solvents used in chemical processes has led to the development of technologies based on supercritical carbon dioxide (scCO2 ... [more ▼]

The ongoing search for environmentally friendlier alternative to the organic solvents used in chemical processes has led to the development of technologies based on supercritical carbon dioxide (scCO2), which is non-flammable, non-toxic and relatively inert fluid. Polymer chemistry does not escape this trend and last achievements in the field of polymer synthesis in scCO2 are reviewed here. Without claiming to be exhaustive, we go through and discuss the benefits of the main polymerization processes in scCO2 including homogeneous, precipitation, dispersion, suspension and emulsion systems. A particular attention is drawn to water/carbon dioxide emulsion polymerization and to the suited surface active agents. This review also underlines that heterogeneous polymerization based on CO2 is more than a strategy for reducing the ecological footprint of the polymer production but it allows structuring the polymer materials into particles or highly interconnected macroporous networks. [less ▲]

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See detailSur les définitions de Dieu. Entretien avec Valère Novarina
Dubouclez, Olivier ULg; Novarina, Valère

in Littérature (2014)

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See detailComment finir, ou la prière faite au théâtre
Dubouclez, Olivier ULg

in Littérature (2014, December)

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See detailLes corps des scientifiques et de l’intellectuel dans la revue La recherche
Dondero, Maria Giulia ULg

in Havelange, Carl (Ed.) La lettre et l'image (2014, December)

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See detailLe relief de Neumagen et les bibliothèques antiques
Marganne, Marie-Hélène ULg

in Capasso, Mario; De Nonno, Mario (Eds.) Scritti in memoria di Paolo Radiciotti (2014)

Mise en contexte du relief de Neumagen aujourd'hui disparu représentant une bibliothèque avec des rouleaux de papyrus et recherches sur les circonstances de la publication, à Liège, en 1670, par l ... [more ▼]

Mise en contexte du relief de Neumagen aujourd'hui disparu représentant une bibliothèque avec des rouleaux de papyrus et recherches sur les circonstances de la publication, à Liège, en 1670, par l'imprimeur Jean Matthias Hovius, des Antiquitatum et Annalium Trevirensium libri XXV de Ch. Brouwer et J. Masen contenant la gravure de ce relief. [less ▲]

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See detailFamily Members of Patients with Abdominal Aortic Aneurysms are at Increased Risk for Aneurysms: Analysis of 618 Probands and their Families from the Liege AAA Family Study.
SakalihasanN, Natzi ULg; Defraigne, Jean-Olivier ULg; Kerstenne, Marie-Ange et al

in Annals of vascular surgery (2014), 28

BACKGROUND: The objectives were to answer the following questions using a well-characterized population in Liege, Belgium: 1) what percentage of abdominal aortic aneurysm (AAA) patients have a positive ... [more ▼]

BACKGROUND: The objectives were to answer the following questions using a well-characterized population in Liege, Belgium: 1) what percentage of abdominal aortic aneurysm (AAA) patients have a positive family history for AAA, 2) what is the prevalence of AAAs among relatives of AAA patients; and 3) do familial and sporadic AAA cases differ in clinical characteristics. METHODS AND RESULTS: Unrelated AAA patients diagnosed at the Cardiovascular Surgery Department, University Hospital of Liege, Belgium, between 1999 and 2012 were invited to the study. A detailed family history was obtained in interviews and recorded using Progeny software. In the initial interview 62 (10%) of the 618 AAA patients reported a positive family history for AAA. We divided the 618 patients into two study groups: Group I: 296 AAA patients (268; 91% males) were followed up with computerized tomography combined with positron emission tomography, and Group II: 322 AAA patients (295; 92% males) whose families were invited to ultrasonography screening. Ultrasonography screening identified 24 new AAAs among 186 relatives (>/= 50 years) of 144 families yielding a prevalence of 13%. The highest prevalence (25%) was found among brothers. By combining the number of AAAs found by ultrasonography screening with those diagnosed previously the observed lifetime prevalence of AAA was estimated to be 32% in brothers. The familial AAA cases were more likely to have a ruptured AAA than the sporadic cases (8% vs. 2.4%; P<0.0001). CONCLUSIONS: The findings confirm previously found high prevalence of AAA among brothers, support genetic contribution to AAA pathogenesis and provide rationale for targeted screening of relatives of AAA patients. [less ▲]

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See detailLes Phénomènes
Dewalque, Arnaud ULg; Seron, Denis ULg

in Philosophie (2014), 124

Le présent numéro thématique explore quelques aspects de la question de la phénoménalité. Les trois premiers textes portent sur les phénomènes sensibles: sur le nombre des sens (Brentano), le traitement ... [more ▼]

Le présent numéro thématique explore quelques aspects de la question de la phénoménalité. Les trois premiers textes portent sur les phénomènes sensibles: sur le nombre des sens (Brentano), le traitement des phénomènes sensibles dans la phénoménologie de Husserl (Stumpf) et l'héritage du phénoménisme de Mach dans le néokantisme de Natorp (Palette). Les contributions suivantes s’inscrivent dans le cadre du débat contemporain sur la conscience phénoménale. Elles discutent la pertinence et les difficultés d’une approche phénoménologique du monde (Uriah Kriegel), de l’intentionnalité (Dan Zahavi) et du mental (Dewalque & Seron). [less ▲]

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See detailExiste-t-il des phénomènes mentaux?
Dewalque, Arnaud ULg; Seron, Denis ULg

in Philosophie (2014), 124

This paper offers a critical discussion of the so-called argument from the transparency of experience. We recall of the argument against the historical background of phenomenal anti-dualism (Natorp, Wundt ... [more ▼]

This paper offers a critical discussion of the so-called argument from the transparency of experience. We recall of the argument against the historical background of phenomenal anti-dualism (Natorp, Wundt, Russell) and identify three difficulties of it. Eventually, we propose an alternative view, which we call phenomenological dualism. On the proposed view, there is a sense in which our mental states may be said to appear to us, hence there is a sense to say that there are mental phenomena. [less ▲]

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See detailEvaluation of pairwise calibration techniques for range cameras and their ability to detect a misalignment
Lejeune, Antoine ULg; Grogna, David ULg; Van Droogenbroeck, Marc ULg et al

in International Conference on 3D Imaging (IC3D) (2014, December)

Many applications require the use of multiple cameras to cover a larger volume. In this paper, we evaluate several pair-wise calibration techniques dedicated to range cameras. We compare the precision of ... [more ▼]

Many applications require the use of multiple cameras to cover a larger volume. In this paper, we evaluate several pair-wise calibration techniques dedicated to range cameras. We compare the precision of a self-calibration technique based on the movement in front of the cameras to object based calibration. While the self-calibration method is less precise than its counterparts, it yields a first estimation of the transformation between the cameras and permits to detect when the cameras become mis-aligned. Therefore it is useful in a practical situations. [less ▲]

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See detailAthanase Kircher ou l’Oedipe des Temps modernes
Winand, Jean ULg

Conference (2014, November 29)

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See detailVers une "dématérialisation" des droits fondamentaux? Convergence des droits fondamentaux dans une protection fragmentée, à la lumière du raisonnement du juge constitutionnel belge
Rosoux, Géraldine ULg

Doctoral thesis (2014)

Le thèse examine l'articulation tant "procédurale" que "substantielle" des droits fondamentaux, garantis par des dispositions tant constitutionnelles que conventionnelles, et protégés par de multiples ... [more ▼]

Le thèse examine l'articulation tant "procédurale" que "substantielle" des droits fondamentaux, garantis par des dispositions tant constitutionnelles que conventionnelles, et protégés par de multiples juges, tant nationaux qu'européens. [less ▲]

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