Abstract. In this paper we describe a language for reasoning about actions that can be used for modelling and for programming rational agents. We propose a modal approach for reasoning about dynamic domains in a logic programming setting. Agent behavior is specified by means of complex actions which are defined using modal inclusion axioms. The language is able to handle knowledge producing actions as well as actions which remove information. The problem of reasoning about complex actions with incomplete knowledge is tackled and the temporal projection and planning problems is addressed; more specifically, a goal directed proof procedure is defined, which allows agents to reason about complex actions and to generate conditional plans. We give a non-monotonic solution for the frame problem by making use of persistency assumptions in the context of an abductive characterization. The language has been used for implementing an adaptive web-based system.

Abstract. This paper discusses the integration of a Prolog implementation, tuProlog, into the DCaseLP environment for building prototypes of multi-agent systems (MASs). DCaseLP aims at providing the MAS developer with a plethora of specification and implementation languages in order to allow him/her to adopt the best language for each view of the system under specification/implementation. The integration of tuProlog into DCaseLP represents a step forward in this direction and allows the re-use of tools and mechanisms previously developed for the DCaseLP predecessor, CaseLP. 1

Policy-based access control is nowadays a common mechanism to protect data in distributed environments. However, the word policy has been given many different meanings and is used in different contexts. This chapter gives an overview of the existing approaches to logic- and rule-based system behavior specification in the light of the peculiar needs of business and security rules.