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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-Saclay
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
CAUSAL LEARNING FOR DIAGNOSTIC SUPPORT


CAUSAL UNCERTAINTY QUANTIFICATION UNDER PARTIAL KNOWLEDGE AND LOW DATA REGIMES


MICRO VISUALIZATIONS: DESIGN AND ANALYSIS OF VISUALIZATIONS FOR SMALL DISPLAY SPACES
The topic of this habilitation is the study of very small data visualizations, micro visualizations, in display contexts that can only dedicate minimal rendering space for data representations. For several years, together with my collaborators, I have been studying human perception, interaction, and analysis with micro visualizations in multiple contexts. In this document I bring together three of my research streams related to micro visualizations: data glyphs, where my joint research focused on studying the perception of small-multiple micro visualizations, word-scale visualizations, where my joint research focused on small visualizations embedded in text-documents, and small mobile data visualizations for smartwatches or fitness trackers. I consider these types of small visualizations together under the umbrella term ``micro visualizations.'' Micro visualizations are useful in multiple visualization contexts and I have been working towards a better understanding of the complexities involved in designing and using micro visualizations. Here, I define the term micro visualization, summarize my own and other past research and design guidelines and outline several design spaces for different types of micro visualizations based on some of the work I was involved in since my PhD.