Innovating in the textile industry: An uncoordinated dance between firms and their territory?

Considering the process of innovati on development, this paper aimed to examine the eff ect of diff erent dimensions of proximity and the level of coordinati on that exists in a texti le cluster. This study employed a qualitati ve method, based on indepth interviews that were conducted with two leading fi rms in a texti le cluster in Valencia, Spain, which is subject to intense competi ti on from producers in Asia. Firms were selected according to the criteria of innovati on development and opportunity. This is a pilot study that precedes a more ambiti ous one. The results suggested that fi rms' innovati ons are developed in an isolated, disconti nuous, marginal, and uncoordinated way, and clustering has a marginal eff ect. Furthermore, despite high geographical and cogniti ve proximity, low social proximity is maintained by the low level of trust between the fi rms. These fi ndings may be of signifi cant practi cal value for practi ti oners and insti tuti ons. Firms can gain a bett er understanding of the importance of being located in a cluster, as this is a key factor for their survival under intense competi ti on. However, geographical proximity is not suffi cient, and fi rms need to cooperate with each other and share their ideas and experiences. In additi on, insti tuti ons should interact more with companies, speak their language, meet their needs, and devise strong cluster initi ati ves. This study provides a more comprehensive understanding of how insti tuti ons and fi rms interact within a cluster in the process of innovati on development and elaborate upon diff erent dimensions of proximity among fi rm

Measurements of electron emission under electron impact on BN sample for incident electron energy between 10 eV and 1000 eV

International audienceElectron emission measurements have been performed on a BN sample by using a new specific protocol and experimental setup , which allows characterizing electron emission under electron impact on resistive material in a short time and with a wide variety of extracted data: total electron emission yield, emitted electron energy distribution, elastically backscattered electron emission yield and energy efficiency of electron-surface interaction. Methodology, calibration, biases corrections and results are presented in this letter. Results are compared to that measured on another material SiO2. As there are few published data on electron emission at low incident electron energy on BN sample, it is expected that these measurements could be useful for numerous studies implying electron emission on BN surface

Analysis of TerraSAR-X data and their sensitivity to soil surface parameters over bare agricultural fields

International audienceCette recherche a pour objectif de mettre en évidence la contribution des capteurs haute résolution pour une meilleure caractérisation de la surface du sol et pour analyser les effets de la polarisation et de l'angle d'incidence radar. L'objectif de cet article est d'analyser la sensibilité des données haute résolution Terrassar-X sur des sols sans couverture végétale et d'étudier la variabilité spatiale. Les relations entre le coefficient de rétrodiffusion et les paramètres du sol seront étudiés grâce aux images (TerraSAR, Ikonos, SPOT) ainsi que grâce aux mesures de terrain recueillies pendant plusieurs campagnes de terrain en hiver et printemps 2008-2009. Ce travail a été mené sur le bassin de l'Orgeval (France). / Our research aims to show the contribution of high resolution spatial sensors for a better characterization of soil surface, and to analyze polarization effects and radar incidence angle. The objective of this paper is to analyze the sensitivity of very high resolution TerraSAR-X radar data taken over bare soils, and to study the spatial variability. The relationship between backscattering coefficient and soil's parameters (moisture, surface roughness, and texture) will be examined by means of satellite images (TerraSAR, Ikonos, SPOT), as well as ground truth measurements, recorded during several field campaigns in the winter and spring of 2008 and 2009. This study is carried out on Orgeval catchment (France)

Analysis of TerraSAR-X data sensitivity to bare soil moisture, roughness, composition and soil crust

Le comportement du signal radar TerraSAR-X en fonction des paramètres du sol (rugosité, humidité, structure) a été analysé sur des données 2009 et 2010. Les résultats montrent que la sensibilité du signal radar à l'humidité est plus importante pour des faibles incidences (25° en comparaison à 50°). Pour des fortes valeurs d'humidité, le signal TerraSAR-X est plus sensible à la rugosité du sol à forte incidence (50°). La forte résolution spatiale des données TerraSAR-X (1 m) permet de détecter la croûte de battance à l'échelle intra parcellaire. / Soils play a key role in shaping the environment and in risk assessment. We characterized the soils of bare agricultural plots using TerraSAR-X (9.5 GHz) data acquired in 2009 and 2010. We analyzed the behavior of the TerraSAR-X signal for two configurations, HH-25° and HH-50°, with regard to several soil conditions: moisture content, surface roughness, soil composition and soil-surface structure (slaking crust).The TerraSAR-X signal was more sensitive to soil moisture at a low (25°) incidence angle than at a high incidence angle (50°). For high soil moisture (N25%), the TerraSAR-X signal was more sensitive to soil roughness at a high incidence angle (50°) than at a low incidence angle (25°). The high spatial resolution of the TerraSAR-X data (1 m) enabled the soil composition and slaking crust to be analyzed at the within-plot scale based on the radar signal. The two loamy-soil categories that composed our training plots did not differ sufficiently in their percentages of sand and clay to be discriminated by the X-band radar signal.However, the spatial distribution of slaking crust could be detected when soil moisture variation is observed between soil crusted and soil without crust. Indeed, areas covered by slaking crust could have greater soil moisture and consequently a greater backscattering signal than soils without crust

ID-HALL, a new double stage Hall thruster design. I. Principle and hybrid model of ID-HALL

International audienceIn Hall thrusters, ions are extracted from a quasineutral plasma by the electric field induced by the local drop of electron conductivity associated with the presence of a magnetic barrier. Since the electric field is used both to extract and accelerate ions and to generate the plasma, thrust and specific impulse are not independent in a Hall thruster. There is a need for versatile thrusters that can be used for a variety of maneuvers, i.e., that can operate either at high thrust or at high specific impulse for a given power. The double stage Hall thruster (DSHT) design could allow a separate control of ionization and acceleration, and hence separate control of thrust and specific impulse. In the DSHT configuration, a supplementary plasma source (ionization stage), independent of the applied voltage, is added and placed upstream of the magnetic barrier (acceleration stage). The DSHT concept is also well adapted to the use of alternative propellants, lighter and with a less efficient ionization than xenon. Several designs of double stage Hall thrusters have been proposed in the past, but these attempts were not really successful. In this paper, we present a brief review of the main DSHT designs described in the literature, we discuss the relevance of the DSHT concept, and, on the basis of simple physics arguments and simulation results, we propose a new design, called ID-HALL (Inductive Double stage HALL thruster). In this design, the ionization stage is a magnetized inductively coupled RF plasma. The inductive coil is inside the central cylinder of the thruster and located nearby the acceleration stage. Preliminary modeling results of this DSHT are described. Published by AIP Publishing. https://doi

La fin de la condition féminine ?

« Le colloque Comprendre la Ve République nous apparaît comme lune des trop rares manifestations scientifiques organisées pour commémorer la naissance dun régime politique aujourdhui quasiment accepté par tous. La comparaison avec la déferlante du 40e anniversaire de Mai 68 pose demblée la question du tri mémoriel, mais nous renvoie aussi à des problématiques spécifiques de lhistorien. () Le décalage entre la logique mémorielle et la volonté critique du chercheur est à la source de ce colloque. De notre point de vue dhistorien, il sagit de privilégier des questionnements sur le long terme, la confrontation entre lévolution dun régime politique et les grandes évolutions de la société française, dans tous les champs possibles, sociaux, économiques, culturels, médiatiques, religieux, internationaux. Si la chronologie politique jalonne évidemment notre réflexion, marquée par des étapes décisives comme la présidentialisation de 1962, la crise de Mai 68, lalternance de 1981 ou la cohabitation de 1986, notre démarche est celle de la synthèse thématique, visant à éviter les perspectives mémorielles ou journalistiques. Cest la raison pour laquelle nous avons demandé aux contributeurs, quils soient historiens, politistes ou sociologues, dadopter un point de vue diachronique qui surplombe le demi-siècle, ce qui navait jamais été tenté jusque là, et pour cause. » (Extrait de l\u27Introduction de J. Garrigues et S. Guillaume.