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Research about the semantics of agent communication languages traditionally sees the opposition between the mentalist and social approaches. In this paper we adopt a mixed approach since we propose a logical framework allowing us to express both the intentional and institutional dimensions of a communicative action. We use this framework to give a semantics for some speech acts representing each of Searle΄s categories except expressives. This semantics relaxes the criticized constraints imposed in FIPA-ACL and also extends this standard with new speech acts and new institutional features to characterise them. It has been implemented in an extension of the Semantic Add-on for the JADE agent development platform, and used in an industrial application in the context of automated B2B exchanges. [ABSTRACT FROM AUTHOR]

Nowadays, more and more artificial agents integrate emotional abilities, for different purposes: expressivity, adaptability, believability... Designers mainly use Ortony et al.'s typology of emotions, that provides a formalization of twenty-two emotions based on psychological theories. But most of them restrain their agents to a few emotions among these twenty-two ones, and are more or less faithful to their definition. In this paper we propose to extend standard BDI (belief, desire, intention) logics to account for more emotions while trying to respect their definitions as exactly as possible. [ABSTRACT FROM AUTHOR]

We investigate belief change in the context of man-machine dialogue. We start from Perrault's approach to speech act theory [12], which proposes on default mechanisms for the reconstruction of the agents' beliefs. Then we review Sadek's [16] critiques and introduce his approach. We point out some shortcomings and present a new framework for the reconstruction of beliefs which contrarily to Perrault's and Sadek's is monotonic. We focus on a particular application, viz. cooperative man-machine dialogues. Our basic notion is that of a topic: we suppose that we can associate a set of topics to every agent, speech act and formula. This allows to speak about the competence of an agent, and the preservation of beliefs. We give an axiomatics and a possible worlds semantics, and we show how the belief state of an agent can be reconstructed after a speech act. [ABSTRACT FROM AUTHOR]

Emotion takes an increasingly important place in the design of intelligent virtual agents. Designers of emotional agents build on theories from cognitive psychology, that describe the cognitive functioning of emotions with two indivisible processes [1,2]: the appraisal process triggers emotions, in particular intense negative emotions to point out threatening stimuli, and the coping process modifies the behaviour to manage these stimuli. Nevertheless, among the existing emotional agents, a lot express emotions triggered by an appraisal process [3] but few have a coping process allowing their emotions to impact their behaviour [4,5,6]. In previous work [7] we provided a formalization of Ortony et al.'s appraisal process [8] in a BDI logic, et al.'s a logic of mental attitudes. The next step is to formalize the coping process in the same framework. Our aim here is to provide the theoretical basis of an agent architecture rather than an implementation. We only give here an overview of our framework (cf. [9,10] for more details). [ABSTRACT FROM AUTHOR]