New model for datasets citation and extraction reproducibility in VAMDC

In this paper we present a new paradigm for the identification of datasets extracted from the Virtual Atomic and Molecular Data Centre (VAMDC) e-science infrastructure. Such identification includes information on the origin and version of the datasets, references associated to individual data in the datasets, as well as timestamps linked to the extraction procedure. This paradigm is described through the modifications of the language used to exchange data within the VAMDC and through the services that will implement those modifications. This new paradigm should enforce traceability of datasets, favour reproducibility of datasets extraction, and facilitate the systematic citation of the authors having originally measured and/or calculated the extracted atomic and molecular data.Comment: 48 page

Federated Identity Management for Research Collaborations

This white-paper expresses common requirements of Research Communities seeking to leverage Identity Federation for Authentication and Authorisation. Recommendations are made to Stakeholders to guide the future evolution of Federated Identity Management in a direction that better satisfies research use cases. The authors represent research communities, Research Services, Infrastructures, Identity Federations and Interfederations, with a joint motivation to ease collaboration for distributed researchers. The content has been edited collaboratively by the Federated Identity Management for Research (FIM4R) Community, with input sought at conferences and meetings in Europe, Asia and North America

Two- and three-field formulations for wave transmission between media with opposite sign dielectric constants

International audienceWe consider a simplified scalar model problem related to Maxwell equations, involving wave transmission between media with opposite sign dielectric and/or magnetic constants. We build two variational formulations equivalent to the model problem. We show that, under some suitable conditions, both formulations are well-posed since they fit into the coercive plus compact framework. Advantages over previous studies is the validity of the formulations in the general case of Lipschitz interface between the two media and L∞ dielectric and magnetic constants. An interesting feature of these formulations is that they allow a simple finite element numerical implementation. © 2006 Elsevier B.V. All rights reserved

Time harmonic wave diffraction problems in materials with sign-shifting coefficients

International audienceSome electromagnetic materials present, in a given frequency range, an effective dielectric permittivity and/or magnetic permeability which are negative. We are interested in the reunion of such a "negative" material and a classical one. More precisely, we consider here a scalar model problem for the simulation of a wave transmission between two such materials. This model is governed by a Helmholtz equation with a weight function in the ΔΔ principal part which takes positive and negative real values. Introducing additional unknowns, we have already proposed in Bonnet-Ben Dhia et al. (2006) [1] some new variational formulations of this problem, which are of Fredholm type provided the absolute value of the contrast of permittivities is large enough, and therefore suitable for a finite element discretization. We prove here that, under similar conditions on the contrast, the natural variational formulation of the problem, although not "coercive plus compact", is nonetheless suitable for a finite element discretization. This leads to a numerical approach which is straightforward, less costly than the previous ones, and very accurate

Implementing in the VAMDC the New Paradigms for Data Citation from the Research Data Alliance

International audienc

IPOPv2 online service for the generation of opacity tables

International audienceIn the framework of the present phase – IPOPv2 – of the international Opacity Project (OP), a new web service has been implemented based on the latest release of the OP opacities. The user may construct online opacity tables to be conveniently included in stellar evolution codes in the format most commonly adopted by stellar physicists, namely the OPAL format. This facility encourages the use and comparison of both the OPAL and OP data sets in applications. The present service allows for the calculation of multi-element mixtures containing the 17 species (H, He, C, N, O, Ne, Na, Mg, Al, Si, S, Ar, Ca, Cr, Mn, Fe and Ni) considered by the OP, and underpins the latest release of OP opacities. This new service provides tables of Rosseland mean opacites using OP atomic data. We provide an alternative to the OPAL opacity services allowing direct comparison as well as study of the effect of uncertainties in stellar modeling due to mean opacities

ArchEthno - a new tool for sharing research materials and a new method for archiving your own research

International audienceThe archiving of ethnographic material is generally considered a blind spot in ethnographic working methods which place more importance on actual investigations and analysis than on how archives are constructed. A team of computer scientists and ethnographers has built an initial tool for sharing ethnographic materials, based on an SQL relational data model that suited the first survey processed but proved difficult to transpose to other surveys. The team developed a new tool based on dynamic vocabularies of concepts which breaks down archiving into three stages. Firstly ethnographers can select and contextualise their survey materials; secondly they structure them in a database according to the research question discovered during their survey; finally, they share this data with other researchers subject to the opinion of an ethics committee whose members are competent in ethnography

A new compactness result for electromagnetic waves. Application to the transmission problem between dielectrics and metamaterials

International audienceWe consider the time-harmonic Maxwell equations, involving wave transmission between media with opposite sign dielectric and/or magnetic coefficients. We prove that, in the case of sign-shifting dielectric coefficients, the space of electric fields is compactly embedded in L 2. We build a three-field variational formulation equivalent to Maxwell system for sign-shifting magnetic coefficients and show that, under some suitable conditions, the formulation fits into the coercive plus compact framework. © 2008 World Scientific Publishing Company

Citation of evolving data in distributed asynchronous infrastructures

International audienceThe VAMDC Consortium intended to find a way for users to cite the datasets accessed through the infrastructure. The Research Data Alliance Data citation working group provided the researchers and data centres communities with a recommendation to identify and cite dynamic data. This recommendation perfectly matched the VAMDC needs: the proposed solution relies on a query centric view and the set-up of a Query Store. Data should be stored in a versioned time-stamped manner and accessed through queries. The Query Store we implemented for VAMDC is interlinked with Zenodo. Since Zenodo is indexed in OpenAIRE and since the latter implements Scholix, VAMDC indirectly implements Scholix via its Query Store. The paper outlines the successes and limitations of the above approach