758 research outputs found

    A new test methodology based on structural resonance for mode I fatigue delamination growth in an unidirectional composite

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    A specific device has been set up to test by vibration resonance the mode I fatigue delamination growth onset of composite laminates. This test system, based on the DCB test specimen, is a mass-spring-specimen dynamic system designed to resonate. The defined operating conditions allow performing delamination propagation tests under imposed load and stopping the test under reproducible conditions, identical to the ones recommended in the ASTM-D6115 standard. This system allows fatigue tests to be driven up to 100Hz, reducing the time taken by a factor of ten without detrimental heat being generated in the material. The effect of frequency on the fatigue delamination growth on mode I has been investigated through a comparison with standard tests performed at 10Hz. A decrease in resistance to the propagation of delamination is observed with the increase in frequency for the composite studied. This frequency effect seems to be a strain rate effect and was taken in consideration by using dynamical critical energy restitution rate for the G-N curve plotting

    « Yerra obedeciendo »

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    La rĂ©Ă©criture du mythe ovidien dans Eco y Narciso, qui semble avoir durablement prĂ©occupĂ© CalderĂłn, est envisagĂ©e sous trois aspects : la nĂ©cessaire adaptation dramatique, facteur d’éloignement de la source, l’appropriation du mythe, qui sĂ©duit notamment parce qu’il rejoint la thĂ©matique de l’erreur des sens, mais aussi une forme de fidĂ©litĂ© retrouvĂ©e au troisiĂšme acte, oĂč le dramaturge tire le meilleur parti de la source-miroir et du jeu d’échos.CalderĂłn has dedicated long-lasting attention to the Ovidian myth as he wrote his «Eco y Narciso». This rewriting is considered from three points of view: the necessary adaptation into drama, the connection of the myth with the Calderonian thought, particularly concerning the error of the senses, and finally, a closer link with the Ovidian text in the third act, with the use of the spring as a mirror as well as that of echoing voices.La reescritura del mito ovidiano en Eco y Narciso, que parece haber preocupado a CalderĂłn durante mucho tiempo, se considera bajo tres aspectos: la necesaria adaptaciĂłn dramĂĄtica, la apropiaciĂłn del mito que seduce en particular en torno a la cuestiĂłn del error de los sentidos, y finalmente una forma de fidelidad mayor en la tercera jornada, cuando el dramaturgo saca el mejor provecho de la fuente-espejo y de los ecos sonoros

    Les chiens dans Los Pazos de Ulloa, et les inflexions d’un roman naturaliste

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    Les figures canines, chiens de chasse familiers ou chiens-loups effrayants, s’avĂšrent autant de dĂ©tails significatifs dans Los Pazos de Ulloa, roman de la ruralitĂ© galicienne qui marque en 1886 l’époque naturaliste de la romanciĂšre Emilia Pardo BazĂĄn. Au dĂ©but du roman, la promiscuitĂ© d’un enfant illĂ©gitime avec les chiens de chasse de son pĂšre, le marquis d’Ulloa, illustre de façon frappante la prĂ©sentation du milieu dans la lignĂ©e de l’esthĂ©tique zolienne. Ce « pays de loups » est l’espace d’un dĂ©terminisme oĂč l’interaction de l’homme et de l’animal est profonde. D’autres figures de chiens ou de loups gĂ©nĂ©ratrices d’angoisse correspondent Ă  l’autre versant du roman, l’exploration psychologique et des souvenirs du roman gothique. La thĂ©matique canine opĂšre ainsi comme un rĂ©vĂ©lateur de la diversitĂ© du roman.Dogs, either familiar retrievers or frightening wolfhounds, may appear as significant details in Emila Pardo BazĂĄn’s novel The Castle of Ulloa, a novel about the northwestern spanish rural world from her naturalist period. A well-known sequence, where a young child – the marquis of Ulloa’s hidden child – walks on all fours among a pack of hounds, stands as a striking treatment of environment following Zola’s aesthetics. The « land of wolves » around the manor is a playground for interaction between animals and men, here an element of naturalist determinism. Besides, other dog or wolf figures, generating fears, are part of another dimension of this novel, based on gothic recollections and psychological exploration. Animal details thus might be revealing of the diversity of inspiration

    MĂ©tamorphoses et fragilitĂ© de l’homme et de ses sens dans les autos sacramentales caldĂ©roniens

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    L’article envisage les limites et les modalitĂ©s d’une reprĂ©sentation des mĂ©tamorphoses du corps humain dans les « autos » caldĂ©roniens. Une telle reprĂ©sentation, contraire Ă  la finalitĂ© du genre, la cĂ©lĂ©bration de l’Eucharistie et donc du corps du Christ sauveur, apparaĂźt comme une tentation rĂ©currente de la dramaturgie, qui se manifeste notamment dans les allĂ©gories des sens, et pourrait trouver une justification dans la rĂ©flexion augustinienne sur les mĂ©tamorphoses.This paper envisages the limits and modes in representing the human body’s metamorphoses in CalderĂłn’s «autos». Such representation, contrary to the purpose of the genre –i.e. the celebration of the Eucharist and of Christ’s body– nevertheless appears as a recurring temptation for the dramatist, in particular through the allegory of the senses, and could find some justification in the Augustinian thought about metamorphoses.El artĂ­culo considera los lĂ­mites y las modalidades de una representaciĂłn de las metamorfosis del cuerpo humano en los autos calderonianos. Esta representaciĂłn, contraria a la finalidad del gĂ©nero, la celebraciĂłn de la EucaristĂ­a y asĂ­ del cuerpo de Cristo, surge varias veces como una tentaciĂłn de la dramaturgia, como en las alegorĂ­as de los sentidos, y podrĂ­a hallar alguna justificaciĂłn en la reflexiĂłn agustiniana sobre las metamorfosis

    Méthode de conception des systÚmes différentiels RF utilisant le formalisme des Modes Mixtes

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    This research work aims to develop analytical tools for the analysis and design of differential systems. While the use of differential circuits in RF reception/transmission chains is increasingly growing, there is no accurate method to study their stability. First the common tools to study RF differential components are introduced. Then, the development of a CAD tool that can be rigorously used to investigate the extrinsic stability of linear differential systems is presented. Finally this tool is applied to study the stability of in a real case. The design addresses a three port component that aims to convert the differential output of digital to analog converter into a single-ended access for a spatial application purpose. This broadband active balun is designed using BiCMOS technology. Measurements are performed and the results are in good agreement with the simulation. All the initial specications are achieved, which validate the approach developed in this study.Ces travaux de recherche visent Ă  introduire et Ă  gĂ©nĂ©raliser l'utilisation des systĂšmes diffĂ©rentiels dans les applications RF et Micro-ondes. En particulier, dans la conception de dispositifs pour les fonctions d'amplification Ă  faible bruit. Pour cela, il est indispensable de dĂ©velopper des outils fiables et rigoureux tels que le formalisme des modes mixtes introduit par Bockelman. C'est dans cet esprit que s'inscrit la premiĂšre phase de l'Ă©tude. Le but Ă©tant de dĂ©velopper un outil pour l'analyse de la stabilitĂ© linĂ©aire des systĂšmes diffĂ©rentiels Ă  trois et quatre accĂšs. Par ailleurs, les interfaces des circuits numĂ©riques ultra-rapides (CNA) sont de topologie diffĂ©rentielle. Ce qui augmente encore l'intĂ©rĂȘt de disposer de mĂ©thodes rigoureuses pour la conception des systĂšmes diffĂ©rentiels. Dans la deuxiĂšme phase de l'Ă©tude la problĂ©matique de l'intĂ©gration systĂšme des CNAs dans les nouvelles gĂ©nĂ©rations des chaines de transmission RF des satellites de tĂ©lĂ©communications est traitĂ©e. La conception d'un balun actif large bande capable d'assurer la conversion de la sortie analogique diffĂ©rentielle du CNA en sortie simple accĂšs (Single-ended) rĂ©fĂ©rencĂ©e par rapport Ă  la masse est dĂ©taillĂ©e. Afin de rĂ©pondre aux contraintes d'intĂ©gration, une technologie BiCMOS SiGe 0.25 ÎŒm est utilisĂ©e pour son implĂ©mentation. Les performances obtenues par la mesure de la puce Silicium rĂ©alisĂ©e respectent les spĂ©cifications techniques initiales de l'application. Ce qui permet de valider la mĂ©thodologie de conception utilisĂ©e. L'objectif final est d'ĂȘtre capable d'intĂ©grer sur un mĂȘme substrat monolithique le CNA et le balun actif large bande de conversion de modes

    Exposer les arts non occidentaux à Paris : nouveaux contextes, nouvelles conceptions

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    Germain Viatte © musĂ©e du quai Branly - Jacques Chirac, photo Cyril Zannettacci M. Germain VIATTE Je suis chargĂ© de revenir un petit peu en arriĂšre, ce qui est toujours utile. C’est malgrĂ© tout, Ă  travers les collections, le fondement mĂȘme du musĂ©e. Une fois de plus, nous avons compris que toute crĂ©ation d’un nouveau musĂ©e est un dĂ©fi. Je vous assure que le mot n’est pas trop fort. C’est un dĂ©fi partagĂ© qui s’inscrit dans le temps, s’appuie sur des prĂ©cĂ©dents institutionnels, reflĂšte les dĂ©b..

    The pro-region of the Kex2 endoprotease of Saccharomyces cerevisiae is removed by self-processing

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    AbstractWe have produced in the baculovirus/insect cells expression system a soluble secreted form of the Saccharomyces cerevisiae Kex2 endoprotease. This secreted enzyme was purified and its NH2-terminal sequence determined. The NH2-terminal sequence started at residue Leu109 of the sequence deduced from the KEX2 gene nucleotide sequence, showing that the Kex2 enzyme is produced as a proenzyme. Residue Leu109 is preceded by a pair of basic amino acid residues (Lys107-Arg108) which is a potential processing site for the Kex2 endopeptidase. Futhermore, expression of an inactive form of this truncated enzyme resulted in the production of a protein with a higher molecular weight. These observations suggest that the pro-region of Kex2 endoprotease is removed by a self-processing event

    Une station météorologique beaucoup moins dispendieuse, performante et plus flexible?

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    Affiche prĂ©sentĂ©e dans le cadre du Colloque de l'ARC, «Des racines et des ailes pour la recherche collĂ©giale», dans le cadre du 85e CongrĂšs de l’Acfas, UniversitĂ© McGill, MontrĂ©al, les 8 et 9 mai 2017.Il existe sur le marchĂ© plusieurs systĂšmes standards d’acquisition de donnĂ©es mĂ©tĂ©orologiques. Ces systĂšmes sont coĂ»teux, leur mode de fonctionnement offre peu d'options, et les utilisateurs sont dĂ©pendants des fabricants quant au service et aux piĂšces de rechange spĂ©cifiques. La chaire de recherche TERRE a dĂ©veloppĂ© une station mĂ©tĂ©orologique alternative rĂ©duisant ces contraintes. Nous avons d’abord conçu la station expĂ©rimentale Ă  partir de la technologie Arduino (petits automates programmables). Les dessins techniques ont Ă©tĂ© rĂ©alisĂ©s Ă  l’aide du logiciel VISIO. La station a Ă©tĂ© fabriquĂ©e par nos techniciens et sa programmation rĂ©alisĂ©e par des Ă©tudiants stagiaires en gĂ©nie Ă©lectrique. Elle a Ă©tĂ© testĂ©e dans le but de comparer ses performances avec celles d'une station standard et commerciale. Les deux Ă©quipements ont Ă©tĂ© montĂ©s en parallĂšle et branchĂ©s sur huit instruments de mesures installĂ©s sur un mĂąt mĂ©tĂ©orologique. Les donnĂ©es sur la vitesse et l’orientation des vents, la tempĂ©rature, la pression, l’humiditĂ© relative et l’ensoleillement Ă©taient enregistrĂ©es en simultanĂ© par les deux modules. L’analyse comparative des rĂ©sultats rĂ©vĂšle une excellente corrĂ©lation des mesures faites par les deux stations. Notre station expĂ©rimentale, qui coĂ»te 5 Ă  10 fois moins cher qu’un Ă©quipement commercial, comporte plusieurs fonctions au choix pour les utilisateurs, peut ĂȘtre jumelĂ©e Ă  une application cellulaire et offre des fonctions de contrĂŽle supplĂ©mentaires

    Health Economic Evaluation of a High and Low Molecular Weight Hyaluronic Acid Formulation for the Treatment of Knee Osteoarthritis. Post Hoc Analyses from a Randomized Clinical Trial.

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    peer reviewed[en] INTRODUCTION: In a recent randomized placebo-controlled trial, a single intra-articular injection of a high and low molecular weight hyaluronic acid formulation (HA-HL) was shown to be effective in providing a clinically meaningful reduction in pain and functional limitation up to 24 weeks in subjects with painful knee osteoarthritis (OA). The objective of this post hoc analyses is to assess the cost-effectiveness of HA-HL compared with placebo using individual patient data from this clinical trial in a Swiss health care perspective. METHODS: A total of 692 patients fulfilling the inclusion criteria were randomly allocated to HA-HL or placebo groups. Each patient received one intra-articular injection of HA-HL or placebo at baseline and was then followed-up for a total duration of 24 weeks with five follow-up visits (i.e., after weeks 1, 6, 12, 18, and 24). The EQ-5D-5L five-point verbal Likert scale was used to calculate the health utility and the related quality-adjusted life-years (QALYs) using the area-under-the-curve (AUC) method. For the costs, the price of HA-HL in Switzerland was used. The primary threshold for the incremental cost/effectiveness ratio (ICER) below which HA-HL was considered as cost-effective was 91,540 Swiss francs (CHF) per QALY (i.e., US $100,000). RESULTS: No significant difference between the baseline characteristics of the HA-HL group and the placebo group was observed. With a mean ICER of 27,212 CHF per QALY (95% CI 20,135-34,289), HA-HL was considered as cost-effective compared to placebo. Sensitivity analyses (e.g., using lower or upper limit prices or using other threshold values) gave similar results, i.e., ICERs far below the threshold values of cost-effectiveness. CONCLUSIONS: These results confirm the role of HA-HL as a cost-effective therapeutic option in the management of OA. However, more studies taking into account the utilization of other health care resources are needed
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