This paper summarizes the main results developed in the author's PhD Thesis.
The main goal of the Thesis is to provide a formalization of defeasible argumentation oriented towards its computational treatment. In order to do this, an LDS-based logical framework…

The appearance and continuous growth of virtual communities on the web imposes the challenge of coping with the large amount of information and knowledge these communities produce. The Semantic Web with its set of standards and technologies provides the basic…

Effective document retrieval using domain knowledge and semantics is one of the major challenges in Information Retrieval. Over the last years, there has been a growing interest in ontologies as an artifact for human knowledge representation and a critical component…

A fuzzy controller is usually designed by formulating the knowledge of a human expert into a set of linguistic variables and fuzzy rules. As it is well known, the use of prior knowledge can dramatically improve the performance and quality…

A re-design process implies dealing with complex interactions between stakeholders, especially if we are talking about a personalization re-engineered process, which can be applied to an existing web application. In this context, knowledge becomes a main factor of influence, but…

Este artigo apresenta um algoritmo Cultural Extendido para o problema do Despacho Econômico. O Algoritmo Cultural têm cinco categorias de conhecimento. Este trabalho visa demonstrar a aplicação do conhecimento histórico, que objetiva monitorar a busca e armazenar os eventos importantes…

This work extends the semantics and implementation of fuzzy prolog presented in [VGM02] in order to include Default Knowledge capability. The new semantic allows non-uniform default assumptions and has Closed World Assumption (CWA) and Open World Assumption (OWA) as particular…

Current reasoning systems attempt to model an agent's knowledge and interaction with its environment in a symbolic manner. This environment, its world is generally dynamic and changing due to natural evolution or the actions of other agents that are a…

The Semantic Web purports to give computeraccessible meaning to the content of the World Wide Web. The rationale behind this project is to create an environment where all this information could be freely exchanged among diverse entities, yet retaining its…

This paper discusses questions about communication of probabilistic knowledge in the light of current theories of agent communication. It will argue that there is a semantic gap between these theories and research areas related to probabilistic knowledge representation and communication,…