Edelweis Rohrer

In order to incorporate meta-modelling in Description Logic, we add equations between individuals and concepts. We naturally require that the individual and the concept are semantically equal and the interpretation domain should be a well-founded set. In this paper, we consider the Description Logics behind the three OWL 2 profiles extended with meta-modelling and study the problems of checking consistency, classification and instance checking which turn out to be all tractable.

SNOMED-CT is a clinical and medical ontology that covers a wide range of concepts in the health domain. It is mostly used as a standard vocabulary to be referenced in electronic health records of patients. The SNOMED-CT ontology has been formalized with a description logic, the Web Ontology language OWL 2 profile OWL-EL. To integrate electronic health records to SNOMEDCT in an OWL-EL ontology, references to SNOMED-CT concepts in these records are modelled as instances of the referenced concepts. In this paper, the ontological model of this integration is analyzed. As our main contribution, we propose to give solution to some problems of this integration by defining a metamodel layer of SNOMED-CT with its concepts represented also as individuals, using an approach of description logics extended with meta-modelling.

In the last decades, the meta-modelling problem has received increasing attention in the conceptual modelling and semantic web communities. We have proposed a solution to this problem in the context of ontological modelling which consists in extending a fragment of the Web Ontology Language OWL with a meta-modelling constructor to equate instances to classes. Even though there are methodologies and patterns that help the ontology engineer to conceptualize a domain using ontologies, there is a lack of such guides for the meta-modelling approaches that extend OWL. In this work we introduce a design pattern that guides in the conceptualization of domains for which there are requirements at different knowledge levels, in particular for different user perspectives.

In this paper we show that the problem of checking consistency of a knowledge base in the Description Logic ALCM is ExpTime-complete. The M stands for meta-modelling as defined by Motz, Rohrer and Severi. To show our main result, we define an ExpTime Tableau algorithm as an extension of an algorithm for checking consistency of a knowledge base in ALC by Nguyen and Szalas.

Abstract. The modeling of website recommendation systems involves the combination of many features: website domain, metrics of quality, quality criteria, recommendation criteria, user profile, and specific do-main features. When specifying these systems, it must be ensured ...

PurposeWeb site recommendation systems help to get high quality information. The modelling of recommendation systems involves the combination of many features: metrics of quality, quality criteria, recommendation criteria, user profile, and specific domain concepts, among others. At the moment of the specification of a recommendation system it must be guaranteed a right interrelation of all of these features. The purpose of this paper is to model a web site quality‐based recommendation system by an ontology network.Design/methodology/approachIn this paper, the authors propose an ontology network based process for web site recommendation modelling. The ontology network conceptualizes the different domains (web site domain, quality assurance domain, user context domain, recommendation criteria domain, specific domain) in a set of interrelated ontologies. Particularly, this approach is illustrated for the health domain.FindingsBasically, this work introduces the semantic relationships ...

In the last decades, the multilevel problem has received increasing attention in the conceptual modelling and semantic web communities. Recently, we proposed a solution to this problem in the context of ontological modelling which consists in extending the Web Ontology Language OWL with a new multilevel constructor that equates instances to classes. In this work we highlight the advantages of exploiting the reasoning capabilities of OWL ontologies with the proposed multilevel constructor by analizing requirements from a real-world application on the accounting domain.

Ontology design for web sites recommendation in the health area Regina Motz 1, Edelweis Rohrer 1 Abstract. The query of web contents about the health area is an increasing common practice among users with different features. Some of them realize queries with a concrete aim, for ...

Modeling a Web Site Quality-based Recommendation System Edelweis Rohrer Fac. Ingenieria, UdelaR Reissig 565 Montevideo, Uruguay erohrer@fing.edu.uy Regina Motz Fac. Ingenieria, UdelaR Reissig 565 Montevideo, Uruguay rmotz@fing.edu.uy Alicia Diaz LIFIA, Fac. ...

This chapter presents how an ontology network can be used to explicitly specify the relevant features of Semantic Educational Recommender Systems. This ontology network conceptualizes the different domains and features involved in these kind of systems in a set of interrelated ontologies. Basically, this chapter presents a detailed study of the semantic relationships that exist among the ontologies in the network considering learners and educators goals and taking also into account relevance feedback by users. One important contribution of this work is to show how the ontology-based reasoning mechanism can be used to validate the recommendation criteria and to assure flexibility for tailoring the educational resource adequacy features (called Educational Resource Quality).

Abstract. The development of ontologies to the Semantic Web is based on the integration of existing ontologies favoring the modularization and reuse of them. These ontologies are used together in complex applica-tions. However, how they are combined is usually hidden in the ...