A new PhD in Computer Science at IRENav, Dr Imad Afyouni

Imad Afyouni made the presentation of his PhD thesis at the French Naval Academy on September 2013, 17th. His research work, led at the French Naval Academy Research Institute - IRENav for 4 years, is entitled : "Knowledge Representation and Management in Indoor Mobile Environments".

The jury, composed of:

-* Pr Karine Zeitouni, Professor at the University of Versailles,
-* Pr Hervé Martin, Professor à the University Joseph Fourier of Grenoble 1,
-* Pr Thierry Delot, Professor at the University of Valenciennes,
-* Pr Jacques Tisseau, Professor at ENIB
-* Dr Sergio Ilarri, Associate Professor at the University of Zaragoza (Spain),
-* Pr Christophe Claramunt, Professor at IRENav, supervisor,
-* Dr Cyril RAY, Associate Professor at IRENav, co-supervisor,

awarded him the title of PhD of the Western Brittany University in Computer Sciences, with a summa cum laude distinction.


Dr Imad Afyouni with the jury members

Abstract

The range of applications in ambient information systems progressively evolves from large to small scale environments. This is particularly the case for applications that assist humans in navigation-related activities in indoor spaces (e.g., airports, museums, office buildings). The research presented by this Ph.D. dissertation develops a data and knowledge representation of an indoor environment that takes into account user-centred contextual dimensions and mobile data management issues. We introduce a hierarchical, context-dependent, and feature-based indoor spatial data model. This model takes into account additional contextual dimensions such as time, user profiles, and real-time events. The model is based on a tree structure in which location information is represented at different levels of abstraction. The hierarchical design favours performance and scalability of location-dependent query processing. A query grammar is developed and implemented on top of that model. This query language supports continuous location-dependent queries and takes into account user preferences at execution time. The concept of location granules is introduced at the query execution and presentation levels.

This modelling approach is complemented by the development of a generic architecture for continuous query processing. Several algorithms for location- dependent query processing over indoor moving objects have been designed and implemented. These algorithms include path searches and range queries applied to both static and moving objects. They are based on an incremental approach in order to execute continuous location-dependent queries. The operators and constraints introduced in the query language and the algorithms for location-dependent query processing have been implemented as a database extension of the open source DBMS PostgreSQL, and where the hierarchical network-based indoor data model has been developed at the logical level. Several experiments have been conducted to evaluate the scalability and performance of the whole framework.

Keywords :

Indoor data models, context-aware systems, mobile data management, continuous location-dependent queries, moving objects.