[bull-ia] Stage Master & Thèse – Accès aux données médiatisés par les ontologies – Co-encadrement Paris-Bordeaux


Vous trouverez ci-dessous (et ici: https://www.di.ens.fr/~mthomazo/dimension-dependent-omqa.html) une proposition de stage de 4-6 mois à débuter en février-mars 2019 sur le sujet de l’accès aux données médiatisé par des ontologies, une thématique à la croisée de l’intelligence artificielle et la théorie des bases de données.

Le stage a pour objectif de déboucher sur une thèse de doctorat à l’automne 2019 (dont le financement est déjà pourvu dans le cadre du projet ANR CQFD).

Je vous remercie de bien vouloir diffuser cette offre à vos étudiants.

Bien cordialement,

Meghyn Bienvenu


The LABRI lab in Bordeaux and the Computer Science department of ENS Paris (DIENS) have funding for a co-supervised PhD studentship starting in Fall 2019 under the direction of Meghyn Bienvenu (LaBRI) and Michaël Thomazo (DI ENS). Preferably, the PhD would be preceded by a Master’s internship (4-6 months duration) taking place during the period February-July 2019. We are currently looking for a highly motivated student interested in such an internship.

The topic of the Master’s internship and PhD position is ontology-based data access, a subject at the crossroads of artificial intelligence and database theory.

Nowadays, there is a wealth of data available, and the real challenge for an individual is to be able to easily find and understand the parts of the data that are relevant to that individual’s information needs. Ontology-based data access (OBDA) is a novel approach to data access and integration that exploits the domain knowledge provided by ontologies to make it easier for users to query data. Ontologies, which are typically expressed using logic-based languages, allow one to introduce a unified and more user-friendly vocabulary for query formulation that abstracts from the way data is stored. Ontologies also serve to represent various types of domain knowledge, making it possible to infer new information via logical reasoning. The OBDA approach is relevant to a wide range of data-intensive applications, and recent industrial projects have witnessed its practical benefits.

A current limitation of the OBDA framework is that the majority of the work to date assumes that data is in either relational or RDF format, and user queries are expressed as conjunctive queries, whereas many other types of data and queries are encountered in practical applications. The goal for the Master’s internship and PhD position is to advance the state-of-the-art on querying dimension-dependent data in the OBDA framework. Indeed, many applications involve manipulating data with a spatial and/or temporal dimension, and it is a challenging task to find suitable combinations of ontology and query languages that are both sufficiently expressive and natural to be useful and sufficiently restricted to support efficient querying.

The Master’s internship and PhD position are part of a larger projet CQFD (Complex ontological Queries over Federated and heterogenous Data), funded by the French research agency ANR, which starts in January 2019. The project involves AI and database researchers from eight research labs from all around France. The main objectives of the project are to extend the OBDA framework to handle a wider range of data models and query languages, to design algorithms for querying federations of heterogenous data sources, and to develop novel system-aware optimizations to enable efficient query answering.


The Master’s internship will preferably take place in Paris at the ENS, though it may be possible to base it in Bordeaux at the student’s request.

The PhD studentship is a three-year full-time position that is scheduled to start in the Fall of 2019 (there is some leeway in the exact starting date). The position will be based in Bordeaux in the LaBRI research lab, with regular funded stays in Paris to visit the co-supervisor.

*Candidate background*

As ontologies are expressed using logic-based formalisms, candidates for the Master’s internship should be familiar and comfortable with first-order logic. Some prior knowledge in one or more of the following areas would be a plus: knowledge representation and reasoning, database (theory or systems), Semantic Web (ontologies), theoretical computer science (in particular, computational complexity).


Potential candidates are invited to send email to the two supervisors to express their interest and ask for more information: Meghyn Bienvenu (meghyn.bienvenu@labri.fr) and Michaël Thomazo (michael.thomazo@inria.fr).

Please note that while at this stage our aim is find a student for a Master’s internship, we are also interested in hearing from students with a strong background in relevant topics that would like to start directly with the PhD position.