1,684 research outputs found
Homogenization of sound hard metamaterials in the time domain
International audienceWe present a homogenization method based on a matched asymptotic expansion technique for sound hard materials structured at subwavelength scale. Considering the wave equation in the time domain, jump conditions are derived for the acoustic pressure and the normal velocity across an equivalent interface with non zero thickness. These jump conditions are implemented in a numerical scheme and compared to the results of the direct problem
Compiling Linguistic Constraints into Finite State Automata
International audienceThis paper deals with linguistic constraints encoded in the form of (binary) tables, generally called lexicon-grammar tables. We describe a unified method to compile sets of tables of linguistic constraints into Finite State Automata. This method has been practically implemented in the linguistic platform Unitex
Innovation et gouvernance territoriale : une analyse par les dispositifs
International audienceCette communication vise à présenter les outils méthodologiques d'analyse/évaluation de la gouvernance territoriale élaborés dans le cadre du projet de recherche PSDR Gouv.Innov sur les innovations organisationnelles relatives à la gouvernance territoriale. Il s'agit d'étudier les transformations introduites par les politiques de développement durable au niveau des dispositifs de gouvernance territoriale visant à favoriser une gestion intégrée des espaces ruraux. Dans un contexte de recomposition de l'action publique où les procédures d'aménagement sont plutôt normées par des représentations urbaines, l'accent est mis sur la question des modalités de représentation des activités rurales, pour lesquelles nous faisons l'hypothèse qu'elles sont sous représentées. Les premiers résultats méthodologiques permettent, dans une première partie, de proposer une définition générique et pragmatique de la gouvernance territoriale et de préciser la notion de dispositifs de gouvernance comme objet d'observation. A partir de cette définition une grille d'analyse permettant d'appréhender l'ensemble des dimensions en jeu dans les processus de gouvernance territoriale est élaborée. Dans la deuxième partie nous explorons l'intérêt de la notion de dispositif pour observer les processus de gouvernance et proposons une grille de collecte et de structuration des informations pour constituer des chroniques des dispositifs étudiés. / This paper seeks to present the methodological tools used in the analysis/evaluation of territorial governance developed during research undertaken within the framework of the PSDR Gouv-Innov project on organisational innovations with respect to territorial governance. It involves the study of the changes resulting from the emergence of sustainable development policies in territorial governance systems aiming to implement the integrated management of rural areas. In a context of changes in the way in which public action is implemented (for instance, public-private partnerships), where development procedures are usually standardised by urban representations, the emphasis is placed on the issue of the representation of rural activities, the hypothesis being that they are under-represented. The initial methodological results lead, in the first instance, to a proposition for a generic and pragmatic definition of territorial governance and a clarification of the notion of governance systems as objects of observation. This definition can be used as the basis of a framework to address all the analytical dimensions of the territorial governance process. In the second part, the authors explore the idea of system in order to observe governance processes and suggest a matrix for the collection and structuring of information in order to report on the studied systems
Comment étudier (analyser) la gouvernance territoriale ? Mise à l'épreuve d'une grille de lecture
International audienceDans cet article nous présentons une grille d'analyse de la gouvernance territoriale que nous avons construite dans le cadre d'un projet de recherche pluridisciplinaire à partir d'une définition commune de la gouvernance territoriale. La gouvernance territoriale est devenue une question centrale dans le développement territorial et un enjeu pour l'élaboration des politiques publiques. Elaborer une grille d'analyse sur la gouvernance territoriale ne va pas de soi ; nous illustrerons son opérationnalisation à partir des travaux de terrain réalisés dans trois situations dans la région de Languedoc Roussillon. Les dispositifs et outils sont contextuels et les modes de gouvernances pluriels selon les objectifs et les dynamiques antérieures. Enfin nous en tirerons des enseignements pour l'étude de la gouvernance tant sur la production des connaissances que sur l'opérationnalité de cette grille. / In this paper we present an analytical framework of territorial governance that we built as part of a multidisciplinary research project based on a common definition of territorial governance. Territorial governance has become a central issue in regional development and a challenge for public policy. Develop an analytical framework on territorial governance does not just happen, and we illustrate its operationalization based on fieldwork conducted in three situations in Languedoc-Roussillon. Devices and tools are contextual and plural forms of governance based on the objectives and dynamics earlier. Finally we will draw lessons for the study of governance both in the production of knowledge about the operational capability of the grid
PIONIER: a visitor instrument for the VLTI
PIONIER is a 4-telescope visitor instrument for the VLTI, planned to see its
first fringes in 2010. It combines four ATs or four UTs using a pairwise ABCD
integrated optics combiner that can also be used in scanning mode. It provides
low spectral resolution in H and K band. PIONIER is designed for imaging with a
specific emphasis on fast fringe recording to allow closure-phases and
visibilities to be precisely measured. In this work we provide the detailed
description of the instrument and present its updated status.Comment: Proceedings of SPIE conference Optical and Infrared Interferometry II
(Conference 7734) San Diego 201
Highlights from the Pierre Auger Observatory
The Pierre Auger Observatory is the world's largest cosmic ray observatory.
Our current exposure reaches nearly 40,000 km str and provides us with an
unprecedented quality data set. The performance and stability of the detectors
and their enhancements are described. Data analyses have led to a number of
major breakthroughs. Among these we discuss the energy spectrum and the
searches for large-scale anisotropies. We present analyses of our X
data and show how it can be interpreted in terms of mass composition. We also
describe some new analyses that extract mass sensitive parameters from the 100%
duty cycle SD data. A coherent interpretation of all these recent results opens
new directions. The consequences regarding the cosmic ray composition and the
properties of UHECR sources are briefly discussed.Comment: 9 pages, 12 figures, talk given at the 33rd International Cosmic Ray
Conference, Rio de Janeiro 201
A search for point sources of EeV photons
Measurements of air showers made using the hybrid technique developed with
the fluorescence and surface detectors of the Pierre Auger Observatory allow a
sensitive search for point sources of EeV photons anywhere in the exposed sky.
A multivariate analysis reduces the background of hadronic cosmic rays. The
search is sensitive to a declination band from -85{\deg} to +20{\deg}, in an
energy range from 10^17.3 eV to 10^18.5 eV. No photon point source has been
detected. An upper limit on the photon flux has been derived for every
direction. The mean value of the energy flux limit that results from this,
assuming a photon spectral index of -2, is 0.06 eV cm^-2 s^-1, and no celestial
direction exceeds 0.25 eV cm^-2 s^-1. These upper limits constrain scenarios in
which EeV cosmic ray protons are emitted by non-transient sources in the
Galaxy.Comment: 28 pages, 10 figures, accepted for publication in The Astrophysical
Journa
ColoLipidGene: Signature of lipid metabolism-related genes to predict prognosis in stage-II colon cancer patients
Lipid metabolism plays an essential role in carcinogenesis due to the requirements
of tumoral cells to sustain increased structural, energetic and biosynthetic precursor
demands for cell proliferation. We investigated the association between expression
of lipid metabolism-related genes and clinical outcome in intermediate-stage colon
cancer patients with the aim of identifying a metabolic profile associated with greater
malignancy and increased risk of relapse. Expression profile of 70 lipid metabolismrelated
genes was determined in 77 patients with stage II colon cancer. Cox regression
analyses using c-index methodology was applied to identify a metabolic-related
signature associated to prognosis. The metabolic signature was further confirmed in
two independent validation sets of 120 patients and additionally, in a group of 264
patients from a public database. The combined analysis of these 4 genes, ABCA1,
ACSL1, AGPAT1 and SCD, constitutes a metabolic-signature (ColoLipidGene) able to
accurately stratify stage II colon cancer patients with 5-fold higher risk of relapse with
strong statistical power in the four independent groups of patients. The identification
of a group of 4 genes that predict survival in intermediate-stage colon cancer patients
allows delineation of a high-risk group that may benefit from adjuvant therapy, and
avoids the toxic and unnecessary chemotherapy in patients classified as low-risk groupThis work was supported by Ministerio de Ciencia e
Innovación del Gobierno de España (Plan Nacional I + D +
i AGL2013–48943-C2–2-R and IPT-2011–1248-060000),
Comunidad de Madrid (P2013/ABI-2728. ALIBIRDCM)
and European Union Structural Funds. CIBEREHD
is funded by the Instituto de Salud Carlos III. This is a
collaborative study between the Molecular Oncology Unit
of The Institute of Advanced Studies of Madrid IMDEA Food
and the Grupo Español Multidisciplinar en Cáncer
Digestivo (GEMCAD
Measurement of the cosmic ray spectrum above eV using inclined events detected with the Pierre Auger Observatory
A measurement of the cosmic-ray spectrum for energies exceeding
eV is presented, which is based on the analysis of showers
with zenith angles greater than detected with the Pierre Auger
Observatory between 1 January 2004 and 31 December 2013. The measured spectrum
confirms a flux suppression at the highest energies. Above
eV, the "ankle", the flux can be described by a power law with
index followed by
a smooth suppression region. For the energy () at which the
spectral flux has fallen to one-half of its extrapolated value in the absence
of suppression, we find
eV.Comment: Replaced with published version. Added journal reference and DO
SPHERE: the exoplanet imager for the Very Large Telescope
Observations of circumstellar environments to look for the direct signal of
exoplanets and the scattered light from disks has significant instrumental
implications. In the past 15 years, major developments in adaptive optics,
coronagraphy, optical manufacturing, wavefront sensing and data processing,
together with a consistent global system analysis have enabled a new generation
of high-contrast imagers and spectrographs on large ground-based telescopes
with much better performance. One of the most productive is the
Spectro-Polarimetic High contrast imager for Exoplanets REsearch (SPHERE)
designed and built for the ESO Very Large Telescope (VLT) in Chile. SPHERE
includes an extreme adaptive optics system, a highly stable common path
interface, several types of coronagraphs and three science instruments. Two of
them, the Integral Field Spectrograph (IFS) and the Infra-Red Dual-band Imager
and Spectrograph (IRDIS), are designed to efficiently cover the near-infrared
(NIR) range in a single observation for efficient young planet search. The
third one, ZIMPOL, is designed for visible (VIR) polarimetric observation to
look for the reflected light of exoplanets and the light scattered by debris
disks. This suite of three science instruments enables to study circumstellar
environments at unprecedented angular resolution both in the visible and the
near-infrared. In this work, we present the complete instrument and its on-sky
performance after 4 years of operations at the VLT.Comment: Final version accepted for publication in A&
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