Search results for "Forma"
showing 10 items of 34540 documents
The close classical T Tauri binary V4046 Sgr: Complex magnetic fields & distributed mass accretion
2011
We report here the first results of a multi-wavelength campaign focussing on magnetospheric accretion processes within the close binary system V4046 Sgr, hosting two partly-convective classical T Tauri stars of masses ~0.9 Msun and age ~12 Myr. In this paper, we present time-resolved spectropolarimetric observations collected in 2009 September with ESPaDOnS at the Canada-France-Hawaii Telescope (CFHT) and covering a full span of 7d or ~2.5 orbital/rotational cycles of V4046 Sgr. Small circularly polarised Zeeman signatures are detected in the photospheric absorption lines but not in the accretion-powered emission lines of V4046 Sgr, thereby demonstrating that both system components host lar…
Spectral analysis of the dipping LMXB system XB 1916-053
2019
Context: XB 1916-053 is a low mass X-ray binary system (LMXB) hosting a neutron star (NS) and showing periodic dips. The spectrum of the persistent emission was modeled with a blackbody component having a temperature between 1.31 and 1.67 keV and with a Comptonization component with an electron temperature of 9.4 keV and a photon index $\Gamma$ between 2.5 and 2.9. The presence of absorption features associated with highly ionized elements suggested the presence of partially ionized plasma in the system. Aims: In this work we performed a study of the spectrum of XB 1916-053, which aims to shed light on the nature of the seed photons that contribute to the Comptonization component. Methods: …
Spectral analysis of the AMXP during its 2018 outburst
2023
The Accreting Millisecond X-ray Pulsar IGR J17591-2342 is a Low Mass X-ray Binary (LMXB) system that went in outburst on 2018 August and it was monitored by the NICER observatory and partially by other facilities. We aim to study how the spectral emission of this source evolved during the outburst by exploiting the whole X-ray data repository of simultaneous observations. The continuum emission of the combined broad-band spectra is on average well described by an absorbed Comptonization component scattering blackbody-distributed photons peaking at (0.8 +/- 0.5) keV by a moderately optically thick corona (tau = 2.3 +/- 0.5) with temperature of (34 +/- 9) keV. A blackbody component with tempe…
Regulación del factor transcripcional Whi7 y la proteinquinasa C en el proceso de Start y el checkpoint de integridad del DNA
2019
Start es el principal punto de control del ciclo celular en el que las células se comprometen a una nueva ronda de división celular. Este punto de control implica la activación irreversible de un programa transcripcional por los complejos Cdc28-Cln a través de la inactivación del represor transcripcional de Start Whi5. En este trabajo se proporcionan nuevas claves sobre cómo Whi7, una proteína relacionada a nivel de secuencia con Whi5, reprime Start. Nuestros resultados demuestran que Whi7 es un parálogo genuino de Whi5. Ambas proteínas colaboran en la represión de Start, aunque presentan diferencias importantes en su regulación que convierten a Whi7 en el represor de Start por excelencia e…
Processus de catégorisation des professionnels par les managers de « l'innovation » : l'exemple des journalistes « experts-métier »
2022
Cette communication présente l’étude des effets de la mise en place d’un dispositif socio-technique lié à « l’innovation » au sein d’un groupe de presse quotidienne régionale, à travers l’appropriation du qualificatif « d’expert-métier » par les journalistes souhaitant être impliqués. Comment, à travers ce titre, les journalistes tendent à faire évoluer la représentation de leur réalité socio-professionnelle ? Comment facilitent-ils l'intégration des valeurs liées à l'entrepreneuriat dans les groupes ?
Les pouvoirs de « l’innovation » : les dispositifs liés à l’innovation comme levier de pouvoir des instances dirigeantes sur la production éditoriale
2022
Cette communication aborde l’intégration d’un dispositif sociotechnique lié à « l’innovation » au sein d’un groupe de presse quotidienne régionale français. Le dispositif étudié est qualifié de « Lab » à partir de sa mise en place en 2012 jusqu’en 2019. Il a d’abord pour mission d’élaborer de nouveaux modèles et processus éditoriaux pour diversifier l’offre et capter un nouveau public, et pour cela d’ajuster les pratiques journalistiques sur les supports numériques au sein de l’entreprise. Mais l’évolution que connait l’entité chargée d’élaborer les solutions porteuses d’un redressement économique, témoigne des tâtonnements et des difficultés persistantes. A partir de 2019, le « Lab » devie…
Saīsinājumu salikteņu lietojums rakstos par jaunuzņēmumiem
2021
Mūsdienu uzņēmējdarbības vide pieprasa skaidru un precīzu valodu, tādēļ veiksmīgai komunikācijai ir būtiska nozīme uzņēmējdarbības panākumos un izaugsmē. Šī pētnieciskā darba mērķis ir izpētīt saīsinājumu lietošanu 40 rakstos par jaunuzņēmumiem un to izmantošanas iemesliem. Lai sasniegtu mērķi un atbildētu uz pētnieciskā darba jautājumiem, tika izmantota kvantitatīvā un kvalitatīvā pētnieciskā metode. Pētījuma rezultāti liecina, ka visbiežāk rakstos par jaunuzņēmumiem tiek izmantoti iniciālismi. Tika secināts, ka saīsinājumu salikteņu izmantošanas mērķis rakstos par jaunuzņēmumiem ir aizstāt garus nosaukumus un frāzes, samazināt lasīšanas laiku un ietaupīt vietu rakstos.
Modeling and Backstepping Control of the Electronic Throttle System
2013
Published version of an article in the journal: Mathematical Problems in Engineering. Also available from the publisher at: http://dx.doi.org/10.1155/2013/871674 Open access Electronic throttle is widely used in modern automotive engines. An electronic throttle system regulates the throttle plate angle by using a DC servo motor to adjust the inlet airflow rate of an internal combustion engine. Its application leads to improvements in vehicle drivability, fuel economy, and emissions. In this paper, by taking into account the dynamical behavior of the electronic throttle, the mechanism model is first built, and then the mechanism model is transformed into the state-space model. Based on the s…
Kinematic and Elastostatic Design Optimisation of the 3-DOF Gantry-Tau Parallel Kinematic Manipulator
2009
Published version of an article in the journal: Modeling Identification and Control. Also available from the publisher:http://dx.doi.org/10.4173/mic.2009.2.1 One of the main advantages of the Gantry-Tau machine is a large accessible workspace/footprint ratio compared to many other parallel machines. The Gantry-Tau improves this ration further by allowing a change of assembly mode without internal link collisions or collisions between the links and end-effector. The reconfigurable Gantry-Tau kinematic design obtained by multi-objective optimisation according to this paper gives the following features: 3-D workspace/footprint ration is more than 3.19, lowest Cartesian stiffness in the workspa…
Euclid preparation: XI. Mean redshift determination from galaxy redshift probabilities for cosmic shear tomography
2021
Ilbert, O., et al. (Euclid Collaboration)