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See detailFive years of comet narrow band photometry and imaging with TRAPPIST
Opitom, Cyrielle ULg; Jehin, Emmanuel ULg; Manfroid, Jean ULg et al

in Bulletin of the American Astronomical Society (2015, November 01), 47

TRAPPIST is a 60-cm robotic telescope in La Silla Observatory [1] mainly dedicated to the study of exoplanets and comets. The telescope is equipped with a set of narrow band cometary filters designed by ... [more ▼]

TRAPPIST is a 60-cm robotic telescope in La Silla Observatory [1] mainly dedicated to the study of exoplanets and comets. The telescope is equipped with a set of narrow band cometary filters designed by the NASA for the Hale-Bopp observing campaign [2]. Since its installation in 2010, we gathered a high quality and homogeneous data set of more than 30 bright comets observed with narrow band filters. Some comets were only observed for a few days but others have been observed weekly during several months on both sides of perihelion. From the images, we derived OH, NH, CN, C[SUB]2[/SUB], and C[SUB]3[/SUB] production rates using a Haser [3] model in addition to the Afρ parameter as a proxy for the dust production. We computed production rates ratios and the dust color for each comet to study their composition and followed the evolution of these ratios and colors with the heliocentric distance.The TRAPPIST data set, rich of more than 10000 images obtained and reduced in an homogeneous way, allows us to address several fundamental questions such as the pristine or evolutionary origin of composition differences among comets. The evolution of comet activity with the heliocentric distance, the differences between species, and from comet to comet, will be discussed. Finally, the first results about the one year campaign on comet C/2013 US10 (Catalina) and our recent work on the re-determination of Haser scalelengths will be presented.[1] Jehin et al., The Messenger, 145, 2-6, 2011[2] Farnham et al., Icarus, 147, 180-204, 2000[3] Haser, Bulletin de l’Académie Royal des Sciences de Belgique,63, 739, 1957 [less ▲]

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See detailNitrogen Isotopic Ratios in Cometary NH2: Implication for 15N-fractionation in Ammonia
Shinnaka, Yoshiharu; Kawakita, Hideyo; Jehin, Emmanuel ULg et al

in Bulletin of the American Astronomical Society (2015, November 01), 47

Isotopic ratios in cometary molecules are diagnostic for the physico-chemical conditions where molecules formed and are processed, from the interstellar medium to the solar nebula. Usually temperatures at ... [more ▼]

Isotopic ratios in cometary molecules are diagnostic for the physico-chemical conditions where molecules formed and are processed, from the interstellar medium to the solar nebula. Usually temperatures at the molecular formation control the fractionation of the heavier element in molecular species, e.g., D-fractionation in water.In cometary volatiles, the [SUP]14[/SUP]N/[SUP]15[/SUP]N ratios in CN have been well observed (Manfroid et al. 2009, A&A, 503, 613, and reference therein) and is consistent with the ratio in HCN (a most probable parent of CN) measured in few comets (Bockelée-Morvan et al. 2008, ApJ, 679, L49). Those ratios are enriched compared to the proto-solar value by a factor of ~3. In contrast to those Nitriles, there are only few reports on [SUP]14[/SUP]N/[SUP]15[/SUP]N ratios in Ammonia (as Amine) (Rousselot et al. 2014, ApJ, 780, L17; Shinnaka et al. 2014, ApJ, 782, L16). Ammonia (NH[SUB]3[/SUB]) is usually the most abundant and HCN is the second most abundant N-bearing volatiles in cometary ice. Especially, recent observations of [SUP]15[/SUP]NH[SUB]2[/SUB] revealed the [SUP]14[/SUP]N/[SUP]15[/SUP]N ratios in NH[SUB]3[/SUB] are comparable to those of CN. However, from the viewpoint of theoretical work, the enrichment of [SUP]15[/SUP]N in cometary NH[SUB]3[/SUB] cannot be reproduced by current chemical network models. Information about the diversity of the [SUP]14[/SUP]N/[SUP]15[/SUP]N ratios in NH[SUB]3[/SUB] of individual comets is needed to understand the formation mechanisms/environments of NH[SUB]3[/SUB] in the early solar system.To clarify the diversity of the [SUP]14[/SUP]N/[SUP]15[/SUP]N ratios in cometary NH[SUB]3[/SUB], we determine the [SUP]14[/SUP]N/[SUP]15[/SUP]N ratios in NH[SUB]3[/SUB] for more than ten comets individually which include not only Oort cloud comets but also short period comets by using the high-resolution optical spectra of NH[SUB]2[/SUB]. These spectra were obtained with both the UVES mounted on the VLT in Chile and the HDS on the Subaru Telescope in Hawaii.The derived [SUP]14[/SUP]N/[SUP]15[/SUP]N ratios in NH[SUB]3[/SUB] for more than ten comets show high [SUP]15[/SUP]N-enrichment compared with the elemental abundances of nitrogen in the Sun by about factor of ~3 and has no large diversity depending on these dynamical properties. We discuss about the origin of the formation conditions of cometary NH[SUB]3[/SUB] and its physico-chemical evolution in the solar nebula based on our and other results.This work was supported by JSPS, 15J10864 (Y. Shinnaka). [less ▲]

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See detailPostures et figures « néo-réactionnaires ». Autour d'un personnage collectif
Durand, Pascal ULg; Sindaco, Sarah ULg

in COnTEXTES : Revue de Sociologie de la Littérature (2015)

Rendre compte du courant dit des « nouveaux réactionnaires » en dressant le portrait du personnage collectif qui lui sert de support tient ici d’une mesure de prudence autant que d’un choix de méthode, à ... [more ▼]

Rendre compte du courant dit des « nouveaux réactionnaires » en dressant le portrait du personnage collectif qui lui sert de support tient ici d’une mesure de prudence autant que d’un choix de méthode, à la faveur d’une double distance créée avec l’objet : distance historique pour commencer, même si celle-ci tendra à se resserrer progressivement autour dudit objet ; distance assurée d’un autre côté par un effort d’abstraction des régularités en fait de rhétorique et de posture caractéristiques du phénomène examiné dans son ensemble. Un phénomène à la fois social et discursif dont les conditions de possibilité et d’efficacité intéresse davantage le propos du présent article que les contenus polémiques dont il se nourrit et les fortes individualités dont il se soutient [less ▲]

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See detailObservations of radio-quiet quasars at 10-mas resolution by use of gravitational lensing
Jackson, Neal; Tagore, Amitpal S.; Roberts, Carl et al

in Monthly Notices of the Royal Astronomical Society (2015), 454

We present Very Large Array detections of radio emission in 4 four-image gravitational lens systems with quasar sources: HS 0810+2554, RX J0911+0511, HE 0435-1223 and SDSS J0924+0219, and extended Multi ... [more ▼]

We present Very Large Array detections of radio emission in 4 four-image gravitational lens systems with quasar sources: HS 0810+2554, RX J0911+0511, HE 0435-1223 and SDSS J0924+0219, and extended Multi-Element Remote Linked Interferometer (e-MERLIN) observations of two of the systems. The first three are detected at a high level of significance, and SDSS J0924+0219 is detected. HS 0810+2554 is resolved, allowing us for the first time to achieve 10-mas resolution of the source frame in the structure of a radio-quiet quasar. The others are unresolved or marginally resolved. All four objects are among the faintest radio sources yet detected, with intrinsic flux densities in the range 1-5 μJy; such radio objects, if unlensed, will only be observable routinely with the Square Kilometre Array. The observations of HS 0810+2554, which is also detected with e-MERLIN, strongly suggest the presence of a mini active galactic nucleus, with a radio core and milliarcsecond scale jet. The flux densities of the lensed images in all but HE 0435-1223 are consistent with smooth galaxy lens models without the requirement for smaller scale substructure in the model, although some interesting anomalies are seen between optical and radio flux densities. These are probably due to microlensing effects in the optical. [less ▲]

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See detailPied douloureux de l'enfant sportif
Kaux, Jean-François ULg

Conference (2015, November 01)

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See detailReport on the ground-based observation campaign of 67P/Churyumov-Gerasimenko
Jehin, Emmanuel ULg

in Bulletin of the American Astronomical Society (2015, November 01), 47

Rosetta gets closer to the nucleus than any previous mission, and returns wonderfully detailed measurements from the heart of the comet, but at the cost of not seeing the large scale coma and tails. The ... [more ▼]

Rosetta gets closer to the nucleus than any previous mission, and returns wonderfully detailed measurements from the heart of the comet, but at the cost of not seeing the large scale coma and tails. The ground-based campaign fills in the missing part of the picture, studying the comet at about 1000 km resolution, and following how the overall activity of the comet varies. These data provide context information for Rosetta, so changes in the inner coma seen by the spacecraft can be correlated with the phenomena observable in comets. This will not only help to complete our understanding of the activity of 67P, but also to allow us to compare it with other comets that are only observed from the ground.The ground-based campaign includes observations with nearly all major facilities world-wide. In 2014 the majority of data came from the ESO VLT, as the comet was still relatively faint and in Southern skies, but as it returns to visibility from Earth in 2015 it is considerably brighter, approaching its perihelion in August, and at Northern declinations. I will present results from the 2014 campaign, including visible wavelength photometry and spectroscopy, and the latest results from 2015 observations. [less ▲]

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See detailGustave Serrurier-Bovy : un architecte à l’aube de la modernité
Folville, Xavier ULg

in Art nouveau et écologie : Mélanges (2015, November 01)

Abstract A l'extrême fin du 19e siècle, l'Art nouveau s’épanouit sous des formes diversifiées, parfois contradictoires, mais partageant généralement la même volonté de rompre avec l'académisme et l ... [more ▼]

Abstract A l'extrême fin du 19e siècle, l'Art nouveau s’épanouit sous des formes diversifiées, parfois contradictoires, mais partageant généralement la même volonté de rompre avec l'académisme et l'historicisme du siècle finissant. Parmi les acteurs de cet Art nouveau, certains ne retiennent que le côté décoratif d’une nouvelle esthétique. Très tôt cependant, au cœur même de ce mouvement d’avant-garde, apparaissent les prémices du renouvellement qui le condamnera et conduira au Modernisme. Quelques travaux de Gustave Serrurier – mobilier ou architecture – méritent d’être observés sous cet angle. [less ▲]

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See detailGustave Serrurier-Bovy, architecte, commerçant et industriel
Folville, Xavier ULg

in Art nouveau et écologie : Mélanges (2015, November 01)

« Il ne faut pas travailler pour un monde qui disparaît mais pour un monde nouveau dont on peut prévoir l’avènement ». Architecte par vocation et formation, puis commerçant, ensuite créateur et industriel ... [more ▼]

« Il ne faut pas travailler pour un monde qui disparaît mais pour un monde nouveau dont on peut prévoir l’avènement ». Architecte par vocation et formation, puis commerçant, ensuite créateur et industriel, le Liégeois Gustave Serrurier (1858-1910) est rapidement convaincu de la nécessité de lier l’architecture aux arts décoratifs. Il le fait avec la conviction politique et esthétique qu’une production industrialisée permettra de donner au plus grand nombre l’environnement artistique auquel tout être peut prétendre. Il pressent que le temps de l’artisanat est en passe d’être révolu et équipe progressivement ses ateliers de machines modernes. Si ses premières créations restent empreintes de l’esprit constructif des artisans néogothiques, s’il emploie ensuite des jeux de lignes courbes, tendues et maîtrisées, le début du XXe siècle le voit évoluer vers toujours plus de simplicité constructive et plus de rigueur géométrique. Grâce au mobilier, aux objets et aux aménagements d’intérieurs qu’il crée et fait réaliser par la centaine d’ouvriers de ses ateliers liégeois, sa firme prend rapidement une ampleur internationale et se fait remarquer dans les expositions universelles comme celle de Saint-Louis (U.S.A.) en 1904. Anticipant sur ce que seront les motivations d’un Bauhaus, ses préoccupations sociales et esthétiques conduisent Serrurier à imaginer un mobilier de plus en plus économique, rationnellement construit, adapté à l’usage et au lieu de destination, par exemple pour une habitation ouvrière à l’Exposition universelle de Liège en 1905. Là, un mobilier en orme équipe la salle commune égayée d’une frise au pochoir et de rideaux de lin garnis de carrés colorés. On y remarque un meuble à usage multiple, tout à la fois armoire, secrétaire et bibliothèque, sans autre décor que sa composition équilibrée ; banc, table et chaises sont faits d’éléments assemblés par des vis apparentes. C’est à cette même époque que Serrurier développe la ligne “Silex”, particulièrement représentative ; conçue de façon tout à fait originale et pragmatique, exécutée en bois blanc et décorée au pochoir, la plupart des assemblages de menuiserie sont remplacés par des vis apparentes. La découpe des planches se montre économe en matière. Une chaise, objet d’utilité commune, se doit d’être robuste, ergonomique et peu coûteuse à produire : ici, la production en série est aisée et pourra être assurée dans ses ateliers équipés de scies mécaniques et autres machines-outils. A l’examen, une chaise de cette série exprime bien les qualités de designer industriel de son concepteur et le place à l’avant-garde de son temps ; elle illustre aussi ses ambitions, tant sociales qu’esthétiques, et sa volonté d’un « art pour tous ». [less ▲]

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See detailPractices and Approaches in EU Member States to Prevent and End Statelessness
Vonk, Olivier ULg

Report (2015)

This study was commissioned by the European Parliament's Policy Department for Citizens' Rights and Constitutional Affairs at the request of the LIBE Committee. It describes the practices and approaches ... [more ▼]

This study was commissioned by the European Parliament's Policy Department for Citizens' Rights and Constitutional Affairs at the request of the LIBE Committee. It describes the practices and approaches in all EU Member States as regards the prevention and eradication of statelessness. For that purpose the different national practices are assessed in light of the relevant international and European standards. Since proper mechanisms to identify stateless populations are lacking in a majority of Member States, the study addresses the procedures used in determining statelessness and analyses the role of the EU in preventing and reducing statelessness. [less ▲]

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See detailChariklo's size, shape and orientation from stellar occultations
Bérard, Diane; Sicardy, Bruno; Assafin, Marcelo et al

in Bulletin of the American Astronomical Society (2015, November 01), 47

Chariklo is the largest Centaur object known to date, and it is surrounded by dense and narrow rings (Braga-Ribas et al. Nature 508, 72, 2014). The size, shape and orientation of the central body are ... [more ▼]

Chariklo is the largest Centaur object known to date, and it is surrounded by dense and narrow rings (Braga-Ribas et al. Nature 508, 72, 2014). The size, shape and orientation of the central body are important parameters to better understand the dynamics of the rings.In that context, we have analyzed three stellar occultations by Chariklo and its main ring observed on June 3, 2013, April 29, 2014 and June 28, 2014. Elliptical limb fitting to Chariklo’s main body occultation chords has been performed, where we denote a (resp. b) the semi-major (resp. semi-minor) axis of the limb. Preliminary results indicate that Chariklo’s limb is elliptical with axes ratio b/a~0.89. We obtain a~133 km and b~119 km, providing an equivalent radius of R[SUB]equiv[/SUB]=√(ab)~126 km. The rms dispersion of the fit, about 4 km, is compatible with local topographic features on a small icy body. For comparison, an equivalent radius of R[SUB]equiv[/SUB]= 119±5 km, based on thermal data, is given by Fornasier et al, AA 518, L11, 2014, while Duffard et al. AA 568, A79, 2014 estimate a= 122 km and b= 117 km.Our results are obtained under the simplifying assumption that the main ring is circular and that its center coincides with that of Chariklo. Caveats and error bars will be discussed, and dynamical implications will be presented. In particular, rough estimations of the ring apsidal precession rates will be given, as well as constraints on Chariklo's density. [less ▲]

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See detailOutgassing and chemical evolution of C/2012 S1 (ISON)
Dello Russo, Neil; Vervack, Ronald J.; Kawakita, Hideyo et al

in Bulletin of the American Astronomical Society (2015, November 01), 47

Volatile production rates, relative abundances, rotational temperatures, and spatial distributions in the coma were measured in C/2012 S1 (ISON) using long-slit high-dispersion (λ/Δλ ~ 25,000) infrared ... [more ▼]

Volatile production rates, relative abundances, rotational temperatures, and spatial distributions in the coma were measured in C/2012 S1 (ISON) using long-slit high-dispersion (λ/Δλ ~ 25,000) infrared spectroscopy as part of a worldwide observing campaign. Spectra were obtained on UT 2013 October 26 and 28 with NIRSPEC at the W. M. Keck Observatory, and UT 2013 November 19 and 20 with CSHELL at the NASA IRTF. H[SUB]2[/SUB]O was detected on all dates, with production rates increasing by about a factor of 40 between October 26 (R[SUB]h[/SUB] = 1.12 AU) and November 20 (R[SUB]h[/SUB] = 0.43 AU). Short-term variability of H[SUB]2[/SUB]O was also seen as the production rate increased by nearly a factor of two during observations obtained over a period of about six hours on November 19. C[SUB]2[/SUB]H[SUB]6[/SUB], CH[SUB]3[/SUB]OH and CH[SUB]4[/SUB] abundances were slightly depleted relative to H[SUB]2[/SUB]O in ISON compared to mean values for comets measured at infrared wavelengths. On the November dates, C[SUB]2[/SUB]H[SUB]2[/SUB], HCN and OCS abundances relative to H[SUB]2[/SUB]O appear to be close to the range of mean values, whereas H[SUB]2[/SUB]CO and NH[SUB]3[/SUB] were significantly enhanced. We will compare derived chemical abundances in ISON to other comets measured with infrared spectroscopy. [less ▲]

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See detailA rocky planet transiting a nearby low-mass star
Berta-Thompson, Zachory K.; Irwin, Jonathan; Charbonneau, David et al

in Nature (2015), 527

M-dwarf stars—hydrogen-burning stars that are smaller than 60 per cent of the size of the Sun—are the most common class of star in our Galaxy and outnumber Sun-like stars by a ratio of 12:1. Recent ... [more ▼]

M-dwarf stars—hydrogen-burning stars that are smaller than 60 per cent of the size of the Sun—are the most common class of star in our Galaxy and outnumber Sun-like stars by a ratio of 12:1. Recent results have shown that M dwarfs host Earth-sized planets in great numbers: the average number of M-dwarf planets that are between 0.5 to 1.5 times the size of Earth is at least 1.4 per star. The nearest such planets known to transit their star are 39 parsecs away, too distant for detailed follow-up observations to measure the planetary masses or to study their atmospheres. Here we report observations of GJ 1132b, a planet with a size of 1.2 Earth radii that is transiting a small star 12 parsecs away. Our Doppler mass measurement of GJ 1132b yields a density consistent with an Earth-like bulk composition, similar to the compositions of the six known exoplanets with masses less than six times that of the Earth and precisely measured densities. Receiving 19 times more stellar radiation than the Earth, the planet is too hot to be habitable but is cool enough to support a substantial atmosphere, one that has probably been considerably depleted of hydrogen. Because the host star is nearby and only 21 per cent the radius of the Sun, existing and upcoming telescopes will be able to observe the composition and dynamics of the planetary atmosphere. [less ▲]

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See detailMusic and Musicality in Caryl Phillips’s Crossing the River
Mascoli, Giulia ULg

Conference (2015, November 01)

This paper deals with Caryl Phillips, a contemporary British author of Caribbean descent, whose work, both fiction and non-fiction, testifies to his interest in music, both thematically and formally ... [more ▼]

This paper deals with Caryl Phillips, a contemporary British author of Caribbean descent, whose work, both fiction and non-fiction, testifies to his interest in music, both thematically and formally: countless references to music can be found in the titles of his books, in scenes involving musical performances, in the use in the narrative of musical terminology, but also in intriguing structural analogies with musical forms. My proposal is to analyse the influence of music in Phillips’s novel Crossing the River (1993; London: Vintage), which has been described as his most jazzy text. Very much like jazz -- which is for the Barbadian poet Edward Kamau Brathwaite “a cry from the heart of the hurt man”-- Phillips’ writing gives a voice to the victims of history, to shattered individuals in pain whose tragic fate is viewed at once as personal and collective. The novel not only illustrates the thematic overlaps between his narrative and the issues addressed in the lyrics of the African American musical tradition, such as discrimination and family disruption, but also exemplifies the author’s formal musical influence through the recurrent and creative use of meaningful variations in rhythm and of repetitions, which are again focal constituents of jazz. Throughout the novel, especially in the sections framing the narrative, the continual modulation of purposeful words such as “listen”, the variation of rhythm through punctuation and stressed/unstressed syllables, the reiterated elements, create a sonic pattern that goes over and over in the readers’ mind. My contention is that Phillips’ musical language crucially contributes to the emotional impact of his lyrical prose, which generates in the readers mixed feelings of sympathy and disorientation and prevents them from forgetting the characters’ stories which resonate long after closing the book. [less ▲]

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See detailIncapacité de travail prolongée. Revue des facteurs de risque professionnels et des stratégies d'intervention
Somville, Pierre ULg; Mairiaux, Philippe ULg

in Archives des Maladies Professionnelles et de l'Environnement (2015), 76(5), 458-467

Purpose of the study In the context of the general population aging and the increasing cost of work disability, public authorities pay special attention to the employability of workers with health ... [more ▼]

Purpose of the study In the context of the general population aging and the increasing cost of work disability, public authorities pay special attention to the employability of workers with health problems. In order to consider strategies for reducing the duration of disability and promoting the return-to-work, the Belgian Federal Public Service Work and Employment wished to have an update of the available scientific evidence on this topic. Methods This literature review is based on articles published in English between 2001 and 2011 and extracted from the MEDLINE database. The review first part deals with long term incapacity risk factors while the second one describes evidence as regards prevention measures and intervention strategies. Results Some risk factors significantly associated with long term disability have been identified: being employed in heavy jobs, fear-avoidance reactions and psychosocial occupational factors such as job dissatisfaction, lack of work control, insufficient support, poor relationships with colleagues, but also the worker own perception of his ability to return to work. Early detection of these perceived barriers to return to work is needed. With regard to intervention strategies, the review, limited to low back pain associated work absences, supports the interest of ergonomic changes in the working environment and the importance of participative interventions. The communication between the return to work actors (i.e. clinical physicians, occupational physicians, employers, insurers and the worker himself) is a key factor in the success of the intervention. Finally, in heavier workload occupations, promoting a systematic access to a transitory light duty position appears to be an interesting guideline. [less ▲]

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See detailLa mise en scène du travail à distance: proposition d'une lecture goffmanienne
Franssen, Marine ULg; Rondeaux, Giseline ULg

Conference (2015, November)

Cette communication s’appuie sur les résultats issus d’une recherche menée dans une entreprise européenne du secteur des télécommunications, portant sur le travail à distance. Elle valorise en particulier ... [more ▼]

Cette communication s’appuie sur les résultats issus d’une recherche menée dans une entreprise européenne du secteur des télécommunications, portant sur le travail à distance. Elle valorise en particulier les apports des travaux de Goffman dans l’analyse de ce phénomène, tant sur le plan méthodologique que sur le plan de l’analyse. Dans le cadre de cette étude, l’équipe de recherche a élaboré une méthodologie d’observation multifocale, visant à cerner certains aspects du travail à distance généralement oblitérés par la littérature, essentiellement basée sur des pratiques déclaratives. Le recours à cette méthode d’observation permet ainsi de mettre en évidence des stratégies d’interaction mises en place par les acteurs à distance, choisissant de rendre visibles ou, a contrario, de maintenir cachées certaines attitudes lors d’interactions à distance. Par ailleurs, la mobilisation du concept de cadres de l’expérience, au coeur des travaux de Goffman, met également en évidence deux enjeux pour lesquels les différents cadrages d’une même situation influence la perception de dispositifs RH. Les résultats obtenus enrichissent l’appréhension des dispositifs de gestion du travail et du management à distance, en intégrant la compréhension et l’expérience qu’ont les acteurs des dispositifs ainsi que la manière dont ils se les approprient. [less ▲]

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See detailThe harmonic balance method for bifurcation analysis of large-scale nonlinear mechanical systems
Detroux, Thibaut ULg; Renson, Ludovic ULg; Masset, Luc ULg et al

in Computer Methods in Applied Mechanics and Engineering (2015), 296

The harmonic balance (HB) method is widely used in the literature for analyzing the periodic solutions of nonlinear mechanical systems. The objective of this paper is to exploit the method for bifurcation ... [more ▼]

The harmonic balance (HB) method is widely used in the literature for analyzing the periodic solutions of nonlinear mechanical systems. The objective of this paper is to exploit the method for bifurcation analysis, i.e., for the detection and tracking of bifurcations of nonlinear systems. To this end, an algorithm that combines the computation of the Floquet exponents with bordering techniques is developed. A new procedure for the tracking of Neimark–Sacker bifurcations that exploits the properties of eigenvalue derivatives is also proposed. The HB method is demonstrated using numerical experiments of a spacecraft structure that possesses a nonlinear vibration isolation device. [less ▲]

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See detailNumerical modelling of transient cyclic vertical loading of suction caissons in sand
Cerfontaine, Benjamin ULg; Collin, Frédéric ULg; Charlier, Robert ULg

in Geotechnique (2015), 65(12),

This paper presents numerical investigations of the monotonic and cyclic behaviours of suction caissons upon vertical transient loading. Both drained and partially drained conditions are investigated ... [more ▼]

This paper presents numerical investigations of the monotonic and cyclic behaviours of suction caissons upon vertical transient loading. Both drained and partially drained conditions are investigated. Monotonic compression and traction simulations are carried out to qualitatively compare results with the literature and validate the model. They highlight the different modes of reaction of the caisson to both compression and traction loading. A sensitivity analysis points out the strong influence of some parameters on the resistance of the caisson but also on the failure mechanism. The transient behaviour of the caisson upon different kinds of cyclic load signals is analysed. Results reproduce the settlement and pore water pressure accumulations observed during experiments. The influence of the key design parameters on the settlement accumulation is also assessed. Finally a cyclic diagram is proposed to describe the evolution of the final settlement upon different magnitudes of loading. [less ▲]

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See detailElmore D. L'intégrale Frémeaux et Ass.
Sacré, Robert ULg

E-print/Working paper (2015)

Compte rendu Coffret 5 CDs + livret . La Wallon et le Blues , un mariage réussi

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