Ahmed Arara

Contextual ontologies: motivations, challenges, and solutions

Contextual ontologies are ontologies that characterize a concept by a set of properties that vary according to context. Contextual ontologies are now crucial for users who intend to exchange information in a domain. Existing ontology languages are not capable of defining such type of ontologies. The objective of this paper is to formally define a contextual ontology language to support the development of contextual ontologies. In this paper, we use description logics as an ontology language and then we extend it by introducing a new contextual constructor.

Multirepresentation in Ontologies

The objective of this paper is to define an ontology language to support multiple representations of ontologies. In our research, we focus on the logic-based ontology languages. As a matter of fact, we will consider only languages that are based on description logics (DLs). At first, we propose a sub-language of DL as an ontology language. Furthermore we achieve multiple representations of ontological concepts by extending such sub-language through the use of stamping mechanism proposed in the context of multiple representation of spatial databases. The proposed language should offer a modest solution to the problem of multirepresentation ontologies.

Towards Formal Ontologies Requirements with Multiple Perspectives

Ontology is very promising in constructing a conceptual data model that can be very close to reality. Ontologies, as an explicit specification of conceptualization, play an essential role in information exchange and integration. Due to the facts that different perceptions, views, and abstractions, we end up having several representations of the same real world entity. The multi-representation problem is commonly known in the discipline of spatial databases and object-oriented modeling and different solutions have been proposed. Multi-representation ontologies are expected to become crucial due to the increasingly demand of multi-represented concept shareability among different applications and user communities in the same domain of interest. In this paper, we consider the notion of context as an abstraction mechanism to deal with multi-representation ontologies (contextual ontologies). A formal representation language based on modal description logics is proposed to comply with the requirements of multiple perspectives of domain ontology.The proposed representational language will provide constructs that deal with the multi-perspectives needs, and consequently queries can be formulated to deal with the multi-represented entities.

Towards a Contextual Content of Ontologies

In this paper, we propose an ontology representation language that should provide contextual representation and contextual querying. Our proposal relies on the description logics formalism and the stamping mechanism proposed in database field. Our approach consists of defining contextual concepts by adding stamps to constructors of complex concepts. Such stamped constructors are interpreted according to the contexts they hold in their definition. Thus, contextual concepts denote different sets of individuals with varying attributes.

A contextual language approach for multirepresentation ontologies

Taking a step forward from syntactic interoperability to the semantic one has become of a great challenge to researchers in the discipline of computer networking and Internet technology. Ontologies have proved to be the most efficient in providing common understanding among machines and/or humans. Several ontology languages have been proposed. These languages, however, are not capable of defining the multirepresentation ontology — that is: an ontology that characterizes a concept by a variable set of properties in several contexts. Multirepresentation ontologies are becoming very essential to diversified user communities that need to share and exchange information and applications in a domain. The objective of this paper is to define a contextual ontology language to support multiple representations of ontologies. In our research, we focus on the logic-based ontology languages. As a matter of fact, we will consider only languages that are based on description logics (DLs). At first, we propose a sub-language of DL as an ontology language. Furthermore we achieve multiple representations of ontological concepts by extending such sub-language through the use of stamping mechanism proposed in the context of multiple representation of spatial databases. The proposed C — DL language should offer a modest solution to the problem of multirepresentation ontologies.