Axiom weakening is a novel technique that allows for fine-grained repair of inconsistent ontologies. In a multi-agent setting, integrating ontologies corresponding to multiple agents may lead to inconsistencies. Such inconsistencies can be resolved after the integrated ontology has been built, or their generation can be prevented during ontology generation. We implement and compare these two approaches. First, we study how to repair an inconsistent ontology resulting from a voting-based aggregation of views of heterogeneous agents. Second, we prevent the generation of (...) inconsistencies by letting the agents engage in a turn-based rational protocol about the axioms to be added to the integrated ontology. We instantiate the two approaches using real-world ontologies and compare them by measuring the levels of satisfaction of the agents w.r.t. the ontology obtained by the two procedures. (shrink)

Background: The Marathon runners must have the proper technical preparation to reach excellence and to achieve adequate psychological preparation for the race. Against this background, the current study aims to describe the implementation results of a cognitive-behavioral intervention based on psychological skills training for marathon runners.Methods: Fourteen amateur male marathoners with an average age of 30 were trained with various emotional and cognitive control techniques to enhance their performance in competition. Various psychological variables, related to the subjects level of perceived (...) stress, and to qualitative characteristics of their thoughts were measured before and after the target marathon race. Results were analyzed through non-parametric tests for two related samples. The Cohen's d effect size for single-group pretest-posttest repeated measures were also performed.Results: Statistical analysis reveals that, controlling for age and running experience, the intervention decreased significantly the level of perceived stress and the occurrence of negative thoughts before the race, during, and after the race.Conclusion: Training in cognitive control and relaxation techniques, as part of the psychological skills training could determine the quality of performance of marathon runners. (shrink)

Ontologies represent principled, formalised descriptions of agents’ conceptualisations of a domain. For a community of agents, these descriptions may differ among agents. We propose an aggregative view of the integration of ontologies based on Judgement Aggregation (JA). Agents may vote on statements of the ontologies, and we aim at constructing a collective, integrated ontology, that reflects the individual conceptualisations as much as possible. As several results in JA show, many attractive and widely used aggregation procedures are prone to return inconsistent (...) collective ontologies. We propose to solve the possible inconsistencies in the collective ontology by applying suitable weakenings of axioms that cause inconsistencies. (shrink)

The combination of Fuzzy Logics and Description Logics has been investigated for at least two decades because such fuzzy DLs can be used to formalize imprecise concepts. In particular, tableau algorithms for crisp Description Logics have been extended to reason also with their fuzzy counterparts. It has turned out, however, that in the presence of general concept inclusion axioms this extension is less straightforward than thought. In fact, a number of tableau algorithms claimed to deal correctly with fuzzy DLs with (...) GCIs have recently been shown to be incorrect. In this paper, we concentrate on fuzzy \, the fuzzy extension of the well-known DL \. We present a terminating, sound, and complete tableau algorithm for fuzzy \ with arbitrary continuous t-norms. Unfortunately, in the presence of GCIs, this algorithm does not yield a decision procedure for consistency of fuzzy \ ontologies since it uses as a sub-procedure a solvability test for a finitely represented, but possibly infinite, system of inequations over the real interval [0,1], which are built using the t-norm. In general, it is not clear whether this solvability problem is decidable for such infinite systems of inequations. This may depend on the specific t-norm used. In fact, we also show in this paper that consistency of fuzzy \ ontologies with GCIs is undecidable for the product t-norm. This implies, of course, that for the infinite systems of inequations produced by the tableau algorithm for fuzzy \ with product t-norm, solvability is in general undecidable. We also give a brief overview of recently obtained decidability results for fuzzy \ w.r.t. other t-norms. (shrink)