Stéphane JEAN
  • Full Professor
  • Data Engineering

Lecture Activity

I teach in the Computer Science Department of the Science Faculty of the University of Poitiers. I'm the asssistant director of the computer science department. I teach mainly databases courses to Bachelors and Masters degrees:
  • Data Engineering
  • Datawarehouses and Datamining
  • Advanced Topics in Database Systems
  • Databases and Web

Research Activity

Research topics

The aim of my research is to improve the management of data especially in the engineering domains targeted by the ENSMA school (aeronautic, transport, mechanic and energy). In particular, I study the interest of using knowledge models called ontologies (or dictionnaries in engineering domains) which give a formal and consensual description of the concepts of a domain. Most of my work relies on normalized ontologies defined with the PLIB ontology formalism (ISO 13584) which is specialized in the description of engineering data. However as ontology are widely used in the Semantic Web context, I'm also interested in formalisms and languages developped in this context (e.g., RDF, RDF-Schema, OWL or SPARQL).

Contributions

During my phD thesis, I have developped a language called OntoQL designed for managing data described by ontologies held in specialized databases. The particularities of this language compared to Semantic Web query language (especially SPARQL) are: (1) the OntoQL language is independent of a given ontology model. Indeed, it is based on a core ontology models containing the constructors shared by different ontology models and this core ontology model can be extended by the OntoQL language itself, (2) the OntoQL language exploits the linguistic information that may be associated to a conceptual ontology allowing users to express queries in different natural languages and (3) the OntoQL language is compatible with the SQL language. This language and the associated softwares (available at LIAS forge) have been and are used in several thesis, academic projects and industrial applications.
Since my phD thesis I continue to work on semantic databases and associated query languages following two directions: (1) extension of the functionalities and domains of application of these languages and (2) optimization of the associated data management operations when they are done on one or several databases.

PhD students

  • Louise Parkin, Cooperative techniques knowledge bases: Framework and scalability, started in 2019
  • Chayma Sellami, Trust in anonymous social networks, started in 2019.
  • Maxime Gaide, spatio-temporal modelisation based on archeological rules, started in 2021.
  • Maxime Perrot, Construction of  ontologies for the analysis and exploitation of Bimedia's clients data started in 2021.

Previous PhD students

  • Ibrahim dellal, Cooperative techniques for uncertain knowledge bases, 2019
  • Selma Bouarar, Variability-based approach for designing advanced database systems, 2016
  • Géraud Fokou, a framework for relaxing SPARQL queries, 2016
  • Bery Mbaiossoum Leouro, Physical design of ontology based databases, 2014
  • Ilyès Boukhari, Semantic-based Integration and exploitation of requirements, 2014
  • Youness Bazhar, Extension of metamodélisation systems with behavioral semantics, 2013