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Deploying low-cost and full edge-IoT/AI system for optimizing irrigation in smallholder farmers communities
No full textInternational Conference on Intelligent Environments, Biarritz, FRA, 20-/06/2022 - 23/06/2022About 35% of the world's food are produced in small-scale farms while only occupying about 12% of all agricultural land. However, smallholder farmers usually face a number of constraints and the water resource is one of the major constraints. The usage of smart technologies and especially sensor systems in so-called Smart Farming Technologies can be applied to the optimization of irrigation. Regardless of the irrigation technique, soil sensors are promising in providing data that can be used to further reduce the usage of water. However, despite all these possibilities, the smallholder community are still reluctant to step into technology-based systems. There are various reasons but prohibitive cost and complexity of deployment usually appear overwhelming. The PRIMA INTEL-IRRIS project has the ambition to make digital and smart farming technologies attractive & more accessible to these communities by proposing the intelligent irrigation 'in-the-box' concept. This paper describes the low-cost and full edge-IoT/AI system targeting the smallholder farmers communities and how it can provide the intelligent irrigation 'in-the-box' concept
CONVERGENCE OF THE FULLY DISCRETE INCREMENTAL PROJECTION SCHEME FOR INCOMPRESSIBLE FLOWS
No full textThe present paper addresses the convergence of a first order in time incremental projection scheme for the time-dependent incompressible Navier-Stokes equations to a weak solution, without any assumption of existence or regularity assumptions on the exact solution. We prove the convergence of the approximate solutions obtained by the semi-discrete scheme and a fully discrete scheme using a staggered finite volume scheme on non uniform rectangular meshes. Some first a priori estimates on the approximate solutions yield the existence. Compactness arguments, relying on these estimates, together with some estimates on the translates of the discrete time derivatives, are then developed to obtain convergence (up to the extraction of a subsequence), when the time step tends to zero in the semi-discrete scheme and when the space and time steps tend to zero in the fully discrete scheme; the approximate solutions are thus shown to converge to a limit function which is then shown to be a weak solution to the continuous problem by passing to the limit in these schemes
Gratuité des transports : comprendre un débat aux multiples enjeux
No full textInternational audienceLa gratuité est devenue l’un des sujets majeurs des débats portant sur les politiques publiques de mobilité à l’échelle locale. Elle se trouve aujourd’hui au cœur de controverses très vives. Par Arnaud Passalacqua, Université Paris-Est Créteil Val de Marne (UPEC)
Cas pédagogique : FRANCE TELEVISION : mesurer la performance globale de l'activité
No full textAvec cette étude de cas, les étudiants s'initient au contexte de l'audiovisuel français en s'intéressant au pilotage de la performance d'une organisation hybride, entre le secteur marchand et le service public. Ce contexte permet d'appréhender la complexité de la mesure de la performance, entre des objectifs d'activités commerciales et des obligations de service public.Construit sous forme de quatre dossiers, le cas se focalise sur les indicateurs en cherchant à interroger leur capacité de mesure. Ainsi, lors de leurs différentes missions, les étudiants interrogent la capacité des indicateurs chiffrés à évaluer la performance. Infos et ressources sur : https://www.ccmp.fr/collection-ccmp/cas-france-television-mesurer-la-performance-globale-de-lactivit
La Cour de justice confirme la portée des libertés de circulation en matière de fiscalité directe des particuliers
No full textInternational audience[CJUE, 1re ch., 18 mars 2021, aff. C-388/19 (1re esp.), MK c/ Autoridade Tributária e Aduaneira ; CJUE, 2e ch., 29 avr. 2021, aff. C-480/19 (2e esp.), E, en présence de Veronsaajien oikeudenvalvontayksikkö ; CJUE, 1re ch., 15 juill. 2021, aff. C-241/20 (3e esp.), BJ c/ État belge ; CJUE, 7e ch., 9 sept. 2021, aff. C-449/20 (4e esp.), Real Vida Seguros SA c/ Autoridade Tributária e Aduaneira ; CJUE, 5e ch., 21 déc. 2021, aff. C-394/20, (5e esp.), XY c/ Finanzamt V
La Somme, 250 000 ans d’occupation néandertalienne
No full textInternational audienceNeanderthals occupied the Somme valley for almost 250,000 years. Deposits from the Middle Paleolithic are preserved in alluvial sediments or in the loessic cover. Human occupations are mainly in the interglacial or transitional phases (especially at the beginning of the glacial period). During the pleniglacial phases, human groups incursions become much more sporadic, but are not totally absent. In terms of lithic industries, all the «chaînes opératoires» are perfectly mastered (production of blades, points, chips and shaping of bifaces). By analyzing them (notion of methods and techniques) and their association, or even exclusivity, it is possible to identify different cultural technocomplexes. For the first half of the Middle Paleolithic, documentation is still incomplete. However, during the Weichselian, a great deal of variability has been revealed, especially at the end of this period (end of SIM 4/SIM 3) when different cultural groups were dis¬tinguished. This is consistent with the observations made throughout Europe, where regional particularities characterize the end of the Mousterian.Pendant près de 250 000 ans, les Néandertaliens ont fréquenté la vallée de la Somme. Les gisements du Paléolithique moyen y sont conservés dans les sédiments alluviaux ou dans la couverture loessique. Les occupations humaines se placent plutôt dans les phases interglaciaires ou les phases de transition (Début Glaciaire surtout). Durant les phases pléniglaciaires, les incursions de groupes humains deviennent beaucoup plus sporadiques, mais ne sont pas totalement absentes. Du point de vue des industries lithiques, toutes les chaînes opératoires sont parfaitement maîtrisées (production de lames, de pointes, d’éclats, façonnage de bifaces). En analysant les schémas opératoires (notion de taille, de méthode et de technique) et leur combinaison, voire leur exclusivité, il est possible d’identifier des technocomplexes culturels différents. Pour la première moitié du Paléolithique moyen, la documentation est encore lacunaire. Mais durant le Weichselien, une grande variabilité a été mise en évidence, surtout en ce qui concerne la fin de cette période (fin SIM 4/SIM 3) où différents groupes culturels ont été distingués. Cela rejoint les obser¬vations faites sur l’ensemble du territoire européen où les particularismes régionaux caractérisent la fin du Moustérie
Phase diagram and order-disorder transitions in Y0.9Gd0.1Fe2Hx hydrides (x ≥ 2.9)
No full textInternational audienceY0.9Gd0.1Fe2, which crystallize in a C15 cubic structure, can absorb up to 5 H/f.u. and its pressure-composition isotherm displays a multiplateau behavior related to the existence of several hydrides with different crystal structures. At room temperature Y0.9Gd0.1Fe2Hx hydrides (2.9 ≤ x ≤ 5) crystallize in three phases with cubic structure (C1, C2 and C3), two phases with monoclinic structures (M1 and M2), and one phase with orthorhombic structure (O), with the following sequence for increasing H concentration: C1, M1, C2, M2, C3, O. Each phase exists as single phase within a H homogeneity range, and they are separated from each other by two-phase domains. The reductions of crystal symmetry are related to various hydrogen orders into interstitial sites. Weak superstructure peaks were indexed by doubling the cubic cell parameter of the cubic C2 phase. Upon heating, the monoclinic M1 and M2 and the cubic C2 phases undergo order-disorder (O-D) transitions toward a disordered cubic structure CDis. These O-D transitions are reversible with thermal hysteresis effects. The cubic C3 and orthorhombic O phases transform into a disordered cubic phasecompanied by H desorption
Préparation collaborative de dictées : analyse des échanges et des textes produits
No full textInternational audienceThe Twictée device brings together distant classes: their students exchange dictations and their corrections through the Twitter network. The text of these dictations is designed and the sessions prepared by their teachers on an online platform between teachers. To what extent does this preparation device help teachers to make dictation a learning moment in spelling? Does it allow a common reflection on language teaching situations? To answer these questions, we analyse the asynchronous exchanges online during the elaboration of the texts of dictations, through the corpus of documents of preparation of a school year as well as the step-by-step construction of this text by analysing in particular the choices made by the network of teachers during this work of elaboration of dictation texts. Several results emerge concerning the function of dictation (evaluation rather than learning), the content of the exchanges (pedagogical rather than didactic), the difficulty encountered by the teachers in taking into account the complexity of the linguistic system and the temporality of the students' acquisitions.Le dispositif Twictée fait collaborer des classes distantes : leurs élèves échangent des dictées et leurs corrections par le réseau Twitter. Le texte de ces dictées est conçu et les séances préparées par leurs enseignants sur une plateforme en ligne entre enseignants. Dans quelle mesure ce dispositif de préparation aide-t-il les enseignants à faire de la dictée un moment d’apprentissage de l’orthographe ? Permet-il une réflexion commune sur les situations d’enseignement de la langue ? Pour répondre à ces questions, nous analysons les échanges asynchrones en ligne lors de l’élaboration des textes des dictées, à travers le corpus des documents de préparation d’une année scolaire ainsi que la construction pas à pas de ce texte en analysant notamment les choix qu’opère le réseau d’enseignants au cours de ce travail d’élaboration des textes de dictées. Plusieurs résultats se dégagent concernant la fonction de la dictée (évaluation plutôt qu’apprentissage), la teneur des échanges (pédagogiques plutôt que didactiques), la difficulté rencontrée par les enseignants à prendre en compte la complexité du système linguistique et la temporalité des acquisitions des élèves
Effects of mixing and annealing on the optical and mechanical properties of TiO:TaO amorphous coatings
No full textAmorphous mixed titania-tantala coatings are key components of Bragg reflectors in the gravitational wave detectors (GWDs). Attaining the lowest possible values of optical absorption and mechanical losses in the coatings is of paramount importance for GWDs, and this requires a complex optimization of the coating deposition and post-deposition annealing. We present here a systematic investigation of the optical properties and internal friction of amorphous mixed titania-tantala coatings grown by ion beam sputtering. We consider coatings with six different cation mixing ratios and we study them both in the as-deposited and annealed state. By exploiting spectroscopic ellipsometry data and modelling, along with ancillary techniques, we retrieved the dielectric function of the coatings in a wide spectral range. When varying the mixing ratio and performing the annealing we find monotonic trends for most of the aforementioned properties. Remakably, the post-annealing Urbach energy displays a definite minimum for a mixing ratio around 20%, very close to the composition of the coatings showing the lowest optical absorption for GWDs applications. We suggest that the observed minimum in the Urbach energy depends not only on the mixing ratio, but also on the annealing parameters. On the other hand, the minimum coating loss angle was found to be weakly dependent on the considered measurement frequency and to lie within a rather broad range of Ti content, suggesting that the search for an absolute minimum following post-deposition annealing should be rather sought in the study of the best annealing parameters for each specific cation ratio considered. This work constitutes a reference for the optical properties of the amorphous mixed titania-tantala coatings, and highlights the relevance of the Urbach energy in the optimization process of materials for high-performing Bragg reflectors