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…

Humans have always been intrigued by their ability to reason. We have constantly attempted to emulate this process, trying almost everything, from physiological explanations, to sociological accounts. The approach with possibly the longest tradition conceives this process as a mere…

This paper addresses the problem of contour line extraction from scanned topographic maps in poor condition. A novel method is developed, using knowledge of cartography and graphics to extract contours by removing other layers which overlay the contours, and reconstructing…

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,…

Evolutionary algorithms (EAs) are merely blind search algorithms, which only make use of the relative fitness of solutions, but completely ignore the nature of the problem. Their performance can be improved by using new multirecombinative approaches, which provide a good…

Ontologies serve as a mean to establish a conceptually concise basis for communicating knowledge for many purposes. Within the information integration area, ontologies are useful to solve heterogeneity problems. They provide a set of knowledge terms, including the vocabulary, the…

A grande maioria dos Sistemas de Gerenciamento de Aprendizagem predominantemente em uso no ensino com suporte computacional são estáticos e lineares, ou seja, apresentam o mesmo conteúdo instrucional para os diversos estudantes sem considerar o nível de aquisição de conhecimentos…

The design of intelligent agents is a key issue for many applications. Although there is no universally accepted de nition of intelligence, a notion of rational agency has been proposed as an alternative for the characterization of intelligent agency.
Modeling…

Collaborative systems are becoming a widely used tool particularly among professional communities and research groups. They provide a suitable context for distributed people working on the same subject to concentrate their work in a shared place to which everyone has…

The general objective of this thesis is the development of an adaptive technique for extracting knowledge in large databases. Nowadays, technology allows storing huge volumes of information. For this reason, the availability of techniques that allow, as a first stage,…