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Ph.D de

Ph.D
Group : Databases

Un modèle de données pour bibliothèques numériques

Starts on 01/10/2008
Advisor : SPYRATOS, Nicolas

Funding : Bourse pour étudiant étranger
Affiliation : Université Paris-Sud
Laboratory : LRI

Defended on 30/05/2012, committee :
- Mme. CALABRETTO Sylvie, Professeur, INSA Lyon, France (Rapporteur)
- M. LAURENT Dominique, Professeur, Université de Cergy-Pontoise, France (Rapporteur)
- M. DE ROUGEMONT Michel, Professeur, Université Paris II, France (Examinateur)
- M. GOASDOUE François, Maître de Conférences, Université Paris-Sud, France (Examinateur)
- M. SPYRATOS Nicolas, Professeur, Université Paris-Sud, France (Directeur de thèse)
- M. MEGHINI Carlo, Directeur de Recherche, CNR, Italie (Co-directeur de thèse)

Research activities :

Abstract :
Digital Libraries are complex information systems, storing digital resources (e.g., text, images, sound, audio), as well as knowledge about digital or non-digital resources; this knowledge is referred to as metadata. We propose a data model for digital libraries supporting resource identification, use of metadata and re-use of stored resources, as well as a query language supporting discovery of resources. The model that we propose is inspired by the architecture of the Web, which forms a solid, universally accepted basis for the notions and services expected from a digital library. We formalize our model as a first-order theory, in order to be able to express the basic concepts of digital libraries without being constrained by any technical considerations. The axioms of the theory give the formal semantics of the notions of the model, and at the same time, provide a definition of the knowledge that is implicit in a digital library. The theory is then translated into a Datalog program that, given a digital library, allows to efficiently complete the digital library with the knowledge implicit in it. The goal of our research is to contribute to the information management technology of digital libraries. In this way, we are able to demonstrate the theoretical feasibility of our digital library model, by showing that it can be efficiently implemented. Moreover, we demonstrate our model’s practical feasibility by providing a full translation of the model into RDF and of the query language into SPARQL. We provide a sound and complete calculus for reasoning on the RDF graphs resulting from translation. Based on this calculus, we prove the correctness of both translations, showing that the translation functions preserve the semantics of the digital library and of the query language.

Ph.D. dissertations & Faculty habilitations
DECODING THE PLATFORM SOCIETY: ORGANIZATIONS, MARKETS AND NETWORKS IN THE DIGITAL ECONOMY
The original manuscript conceptualizes the recent rise of digital platforms along three main dimensions: their nature of coordination devices fueled by data, the ensuing transformations of labor, and the accompanying promises of societal innovation. The overall ambition is to unpack the coordination role of the platform and where it stands in the horizon of the classical firm – market duality. It is also to precisely understand how it uses data to do so, where it drives labor, and how it accommodates socially innovative projects. I extend this analysis to show continuity between today’s society dominated by platforms and the “organizational society”, claiming that platforms are organized structures that distribute resources, produce asymmetries of wealth and power, and push social innovation to the periphery of the system. I discuss the policy implications of these tendencies and propose avenues for follow-up research.

DISTRIBUTED COMPUTING WITH LIMITED RESOURCES


VALORISATION DES DONNéES POUR LA RECHERCHE D'EMPLO