The paper presents a case study illustrating a collaborative problem solving process in Virtual Communities of Practice. The process relies on the existence of an underlying shared knowledge base – a repository of resources, and is carried out collaboratively by…

A solution of problems in multiagent systems involves representing beliefs of agents immersed in dynamic environments. Observation-based Defeasible Logic Programming (ODeLP) is an argument-based logic programming language that is used to represent an agent’s knowledge in the context of a…

Descoberta de Conhecimento em Bases de Dados" ("Knowledge Discovery in Databases", KDD) é um processo composto de várias fases iniciando com a coleta de dados para o problema e finalizando com a avaliação dos resultados finais. Este trabalho objetiva mostrar…

This article proposes a method for achieving an appropriate balance between the parameters of support, precision, and simplicity during the evolution of classification rules by means of genetic programming. The method includes an adaptive procedure in order to achieve such…

In the last decade several ways to formalize defeasible reasoning have been studied. A particular approach, defeasible argumentation, has been particularly successful to achieve this goal.
The inference process of argument-based systems is based on the interaction of ar- guments…

Defeasible argumentation is one of the approaches that attempt to address the challenges arising when we reason defeasibly, with several formalisms in the literature reaching a mature state. Nowadays, several of them started shifting their semantics towards a dialectical characterization.…

The notion of context and its importance in knowledge representation and nonmonotonic reasoning was first discussed in Artificial Intelligence by John McCarthy.
Ever since, contexts have found many applications in developing knowledge-based reasoning systems.
Defeasible argumentation has gained wide acceptance…

The problem of speeding up ínference has proved to be important in argumentative systems. When computing dialectical structures, several paths are searched (called argumentation lines), many of which will eventually prove useless. Morover, the performance of backward chainers degrades quickly…

En [2] Gerhard Brewka realizó una reconstrucción de la Teoría de Disputación Formal de Nicholas Rescher [5]. En su trabajo, Brewka completó la formalización de la presentación de Dialectics:
A Controversy-Oriented Approach to the Theory 01 Knowledge. El formalismo no..monótono…

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…