Swiss Data Journal: étude de conceptualisation d'un modèle de partage des données de recherche basé sur le concept de Data Paper dans le contexte helvétique

L’ouverture des données de la recherche financées par des fonds publics est au coeur de l’actualité récente, tant au niveau européen qu’à l’échelle helvétique, en raison du message fort porté par la présidence néerlandaise de l’Union européenne, véritable manifeste en faveur de l’accès libre aux résultats de recherche, s’appuyant sur des considérations politiques, économiques et éthiques. Cet engagement a entraîné dans son sillage une réaction similaire du Fond national suisse pour la recherche scientifique. Les acteurs suisses de la recherche, qu’ils soient en charge de la promotion de la science et de l’innovation, institutions académiques, bibliothèques ou chercheurs tentent d’apporter des réponses aux enjeux soulevés par la production toujours plus importante de volume de données et l’évolution des exigences des agences de financement des partenaires européens et internationaux quant à la gestion des données. Dans ce cadre fertile, le rédacteur de ce travail, a été amené à réaliser une étude de conceptualisation sur la mise en place, à l’échelle helvétique, d’une solution de diffusion basée sur le concept de data paper. Ce sont de véritables publications savantes, dont le sujet n’est plus les résultats de l’étude, mais les données produites dans le processus de recherche ayant mené à sa réalisation, afin de pouvoir déterminer si ce type de solution était envisageable et quels en seraient les éléments essentiels. En résulte trois scénarios, qui ont été construits sur la base d’une étude contextuelle prenant en compte les besoins des principaux acteurs du domaine et les notions fondamentales de la gestion des données de recherche et de leur publication. Mais également plus spécifiquement sur le data paper et son influence sur les processus de communication scientifique. Le rédacteur a considéré, une fois les éléments nécessaires acquis, qu’une solution de diffusion basée uniquement sur le type de publication sélectionnée au départ pouvait apporter une plus-value intéressante, mais ne constituait que l’une des facettes de la publication des données de la recherche

Derivation of BGK models for mixtures

International audienceThis paper is devoted to the construction of a BGK operator for gas mixtures. The construction is based as in ([12], [13]) on the introduction of relaxation coefficients and a principle of minimization of the entropy under constraints of moments. These free parameters are com pared with the free parameters introduced in the Thermodynamics of Irr eversible Processes approach of the Navier-Stokes system. At the end t he BGK model is proved to satisfy Fick and Newton law

The Correlation framework: bridging the gap between modeling and analysis for 3D woven composites

International audienceA large variety of dierent descriptors can be employed for describing 3D woven composites. Each of them is targeted to a specic application, ranging from design, weaving, molding, impregnation down to non-destructive testing, imaging and numerical modeling of the actual micro-structure. In order to relate these dierent representations, it is proposed herewith to rely on the inherent weaving pattern as an intrinsic common feature, and to resort to images as a common language to guaranty the continuity of information. To connect these 3D images (either real or synthesized), Digital Volume Correlation (DVC) is called for in order to exploit the conservation of topology. A complete test scenario is devised in which dierent manufactured woven samples are compared to the theoretical textile arrangement. The results conrm the eectiveness of the method

Simulation of forced deformable bodies interacting with two-dimensional incompressible flows: Application to fish-like swimming

International audienceWe present an efficient algorithm for simulation of deformable bodies interacting with two-dimensional incompressible flows. The temporal and spatial discretizations of the Navier-Stokes equations in vorticity stream-function formulation are based on classical fourth-order Runge-Kutta and compact finite differences, respectively. Using a uniform Cartesian grid we benefit from the advantage of a new fourth-order direct solver for the Poisson equation to ensure the incompressibility constraint down to machine zero. For introducing a deformable body in fluid flow, the volume penalization method is used. A Lagrangian structured grid with prescribed motion covers the deformable body interacting with the surrounding fluid due to the hydrodynamic forces and moment calculated on the Eulerian reference grid. An efficient law for curvature control of an anguilliform fish, swimming to a prescribed goal, is proposed. Validation of the developed method shows the efficiency and expected accuracy of the algorithm for fish-like swimming and also for a variety of fluid/solid interaction problems

Simulation of fish escape and swimming toward a predefined goal

We present an immersed boundary method for numerical simulation of a swimming fish. The vorticity transport equation is solved on a Cartesian grid using compact finite dif- ferences. A Lagrangian structured grid defines the fish body and is moving in the surrounding incompressible flow due to the exerted hydrodynamic forces and the torque. An efficient law determining the curvature of a swimming fish is presented which is based on the geometrically exact theory of nonlinear beams and quaternions. Validation of the solver shows the efficiency and expected accuracy of the algorithm for swimming fish simulations. The structure of the wake of a swimming fish is studied, and some common features with the wake of a flapping plate are demonstrated

Dynamic Clustering in Object-Oriented Databases: An Advocacy for Simplicity

International audienceWe present in this paper three dynamic clustering techniques for Object-Oriented Databases (OODBs). The first two, Dynamic, Statistical & Tunable Clustering (DSTC) and StatClust, exploit both comprehensive usage statistics and the inter-object reference graph. They are quite elaborate. However, they are also complex to implement and induce a high overhead. The third clustering technique, called Detection & Reclustering of Objects (DRO), is based on the same principles, but is much simpler to implement. These three clustering algorithm have been implemented in the Texas persistent object store and compared in terms of clustering efficiency (i.e., overall performance increase) and overhead using the Object Clustering Benchmark (OCB). The results obtained showed that DRO induced a lighter overhead while still achieving better overall performance

Biochemical and genetic analysis of RNA cap guanine-N2 methyltransferases from Giardia lamblia and Schizosaccharomyces pombe

RNA cap guanine-N2 methyltransferases such as Schizosaccharomyces pombe Tgs1 and Giardia lamblia Tgs2 catalyze methylation of the exocyclic N2 amine of 7-methylguanosine. Here we performed a mutational analysis of Giardia Tgs2, entailing an alanine scan of 17 residues within the minimal active domain. Alanine substitutions at Phe18, Thr40, Asp76, Asn103 and Asp140 reduced methyltransferase specific activity to <3% of wild-type Tgs2, thereby defining these residues as essential. Alanines at Pro142, Tyr148 and Pro185 reduced activity to 7–12% of wild-type. Structure–activity relationships at Phe18, Thr40, Asp76, Asn103, Asp140 and Tyr148, and at three other essential residues defined previously (Asp68, Glu91 and Trp143) were gleaned by testing the effects of 18 conservative substitutions. Our results engender a provisional map of the Tgs2 active site, which we discuss in light of crystal structures of related methyltransferases. A genetic analysis of S. pombe Tgs1 showed that it is nonessential. An S. pombe tgs1Δ strain grows normally, notwithstanding the absence of 2,2,7-trimethylguanosine caps on its U1, U2, U4 and U5 snRNAs. However, we find that S. pombe requires cap guanine-N7 methylation catalyzed by the enzyme Pcm1. Deletion of the pcm1(+) gene was lethal, as were missense mutations in the Pcm1 active site. Thus, whereas m(7)G caps are essential in both S. pombe and S. cerevisiae, m(2,2,7)G caps are not

Unification of multi-lingual scientific terminological resources using the ISO 16642 standard. The TermSciences initiative

This paper presents the TermSciences portal, which deals with the implementation of a conceptual model that uses the recent ISO 16642 standard (Terminological Markup Framework). This standard turns out to be suitable for concept modeling since it allowed for organizing the original resources by concepts and to associate the various terms for a given concept. Additional structuring is produced by sharing conceptual relationships, that is, cross-linking of resource results through the introduction of semantic relations which may have initially be missing.Comment: 6