Séminaire du 5 octobre 2000

Ontologies : concepts et méthodes

Programme

14h00-15h30
Nicola Guarino : Ontology cleaning: formal analysis of taxonomic relationships
15h30-16h00
Pause
16h00-17h30
Bruno Bachimont : Conceptual modelling and ontology building: methodological principles from linguistics and knowledge engineering

Lieu : Amphithéâtre Gaston Berger - INSA de Lyon

Ontology cleaning: formal analysis of taxonomic relationships (Nicola Guarino)

Résumé : Taxonomies based on a partial-ordering relation commonly known as is-a or class inclusion have become an important tool in conceptual modeling. A clean, well-formed taxonomic structure has significant implications for ontology understanding, reuse, and integration. The intuitive simplicity of taxonomic relations has led however to widespread misuse, making clear the need for rigorous analysis techniques. I will present here a methodology for ontological analysis that focuses on ontological constraints on taxonomic relationships, which are based on the philosophical notions of identity, unity, essence, and dependence. I will demonstrate the effectiveness of this methodology for ontology cleaning, by taking real examples of poorly structured taxonomies and revealing cases of invalid generalization.

Eléments bibliographiques : This work is based on some recent papers written together with Chris Welty (available from our Web site):
- Guarino, N. and Welty, C. 2000. Identity, Unity, and Individuality: Towards a Formal Toolkit for Ontological Analysis. In Proceedings of ECAI-2000: The European Conference on Artificial Intelligence. Berlin, Germany, IOS Press.
- Guarino, N. and Welty, C. 2000. A Formal Ontology of Properties. In Proceedings of 12th International Conference on Knowledge Engineering and Knowledge Management. France, Springer Verlag.
- Guarino, N. and Welty, C. 2000. Ontological Analysis of Taxonomic Relationships. In A. Länder and V. Storey (eds.), Proceedings of ER-2000: The International Conference on Conceptual Modeling. Springer Verlag.

Eléments biographiques : Nicola Guarino is a senior research scientist at the Institute for Systems Theory and Biomedical Engineering of the Italian National Research Council (LADSEB-CNR). For about ten years now he has been actively promoting the study of the ontological foundations of knowledge representation and knowledge engineering with an interdisciplinary approach centered on logic, philosophy, and linguistics. He was chairman of the First International Conference on Formal Ontology in Information Systems (FOIS'98), and program committee member of many workshops and conferences in the field. He is associate editor of the International Journal of Human and Computer Studies, has edited 3 journal special issues on ontology-related topics, and has published more than 30 papers in international journals, books and conferences. His research activities regard ontology design, conceptual modelling, knowledge sharing and integration, logical modeling of physical objects, and ontology-driven information retrieval.

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Conceptual modelling and ontology building: methodological principles from linguistics and knowledge engineering (Bruno Bachimont)

Résumé : Ontologies are conceptual resources for building knowledge-based systems. They are made up of concepts, defined along with their semantics, and organised in more or less structures. Two main issues arise :
- what kind of semantics is relevant to define and describe ontological concepts ?
- what kind of structure is relevant to organise ontological concepts ?
Since most of materials for modelling are available in a linguistic form, we start from linguistics to propose a semantics and a structure for ontologies. However, since ontologies are used in formal systems as knowledge-based systems, linguistic principles must turn into formal principles, for example, those proposed by Nicola. Finally, some concepts cannot be defined by linguistic means. Close attention will by payed to this kind of concepts. Examples come from the audiovisual world as well as from the medical world, domains in which we have designed ontologies.

Eléments bibliographiques :
- B. Bachimont, Engagement sémantique et engagement ontologique: conception et réalisation d'ontologies en ingénierie des connaissances. In Ingénierie des connaissances et nouveaux défis, Eyrolles, 2000.
- B Bachimont: MPEG-7 and ontologies: an editorial perspective. In VSMM-98 workshop on MPEG-7 and ontologies, Tokyo, Japan, Nov. 1998.

Eléments biographiques : Bruno Bachimont is research manager at INA, Institut National de l'Audiovisuel and associate professor at UTC, Université de Technologie de Compiègne, where he teaches logics and philosophy. His research activities mainly concern the problem of representing meaning and apprehending meaning through its inscription on a material medium. Ontologies are a facet of this problem, from the point of view of knowledge representation and formal technics. Other facets are indexing and document management, and the introduction of knowledge representation methods to design document management systems.

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