Ontology-Based Modeling and Recommendation Techniques for Adaptive Hypermedia Systems (Teza de Doctorat) ----------------------------------- ABSTRACT ----------------------------------- The specific problem addressed by the thesis is the problem of providing personalized recommendations of resources to the users of an e-learning application, according their professional competences and interests, with the support of semantic Web technologies, and without requiring explicit feed-back or other intervention from the user. This problem is situated at the confluence of multiple computer science domains, whose technologies were harmonized in order to structure the solution provided by the thesis: e-learning, semantic Web, adaptive hypermedia systems. In order to define thesis solution, some integrally similar approaches oriented to the same entire problem were not available. Instead, each step performed to the final solution was related to the existing approaches and standards which address the corresponding intermediary problem. The main issues addressed for developing a recommender system concern the definition of user model and document model, the methods for these models development, the technique for establishing the recommendations suitable for each particular user, as well as the architecture to include the corresponding functionalities. The main original aspects are: (1) Using ontology as a binder between documents and users: the user profile is defined in terms of the same ontology as the document model. (2) The combination of approaches belonging to different domains. (3) User profile is structured on three levels, competences, interests and fingerprints, and is built on top of IEEE/PAPI. (4) Document model is built on top of IEEE/LOM, including three semantic relation defined. Different parts of the document were separately processed in order to generate semantic differentiated annotations. Also, a solution of workflow modeling for multimedia documents indexing was provided. (5) The hybrid recommender solution adopts a new approach for using domain knowledge in the user and document knowledge to be applied in known recommender techniques. The method of integrating ontology-based domain knowledge into the recommender algorithms is original, as well as the idea of supervising the user conceptual navigation through the ontology used for materials and users. The recommender solution avoiding cold-start issue, and also does not demands user feed-back. (6) Concerning the solution architectural issues, the defined models could be exported from a systems to another. Multiple architectures are possible for the recommender solution: service-oriented architecture adopted independently, or into a grid system, or inside a pervasive environment. As conclusion, the thesis provides a semantic-based approach in the context of the new European higher education law to alleviate and facilitate the dissemination of the current overload of information and resources for teaching and learning in Computer Science. SPEAKER(S) ----------------------------------- Lect.dr. Mihaela BRUT Universitatea Alexandru Ioan Cuza, Facultatea de Informatica Iasi Romania -----------------------------------