SCIFF is a framework thought to specify and verify interaction in open agent societies. The SCIFF language is equipped with a semantics based on abductive logic programming; SCIFF's operational component is a new abductive logic programming proof procedure, also named SCIFF, for reasoning with expectations in dynamic environments. In this article we present the declarative and operational semantics of the SCIFF language, and the termination, soundness, and completeness results of the SCIFF proof procedure, and we demonstrate SCIFF's possible application in the multiagent domain. (http://lia.deis.unibo.it/research/ socs/), and by the MIUR PRIN 2005 projects 2005-011293 (Specifica e verifica di protocolli di interazione fra agenti) and 2005-015491 (Vincoli e preferenze come formalismo unificante per l'analisi di sistemi informatici e la soluzione di problemi reali).

In multiagent systems, agent interaction is ruled by means of interaction protocols. Compliance to protocols can be hardwired in agent programs; however, this requires that only ''certified'' agents interact. In open societies, composed of autonomous and heterogeneous agents whose internal structure is, in general, not accessible, interaction protocols should be specified in terms of the agent observable behaviour, and compliance should be verified by an external entity. In this paper, we propose a Java-Prolog-CHR system for verification of compliance of agents' behaviour to protocols specified in a logic-based formalism (Social Integrity Constraints). We also present the application of the formalism and the system to the specification and verification of the FIPA Contract-Net protocol

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Deontic concepts and operators have been widely used in several fields where representation of norms is needed, including legal reasoning and normative multi-agent systems.The EU-funded SOCS project has provided a language to specify the agent interaction in open multi-agent systems. The language is equipped with a declarative semantics based on abductive logic programming, and an operational semantics consisting of a (sound and complete) abductive proof procedure. In the SOCS framework, the specification is used directly as a program for the verification procedure.In this paper, we propose a mapping of the usual deontic operators (obligations, prohibition, permission) to language entities, called expectations, available in the SOCS social framework. Although expectations and deontic operators can be quite different from a philosophical viewpoint, we support our mapping by showing a similarity Springer 206 M. Alberti, M. Gavanelli et al. between the abductive semantics for expectations and the Kripke semantics that can be given to deontic operators.The main purpose of this work is to make the computational machinery from the SOCS social framework available for the specification and verification of systems by means of deontic operators.

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cplint on SWISH is a web application that allows users to perform reasoning tasks on probabilistic logic programs. Both inference and learning systems can be performed: conditional probabilities with exact, rejection sampling and Metropolis-Hasting methods. Moreover, the system now allows hybrid programs, i.e., programs where some of the random variables are continuous. To perform inference on such programs likelihood weighting and particle filtering are used. cplint on SWISH is also able to sample goals' arguments and to graph the results. This paper reports on advances and new features of cplint on SWISH, including the capability of drawing the binary decision diagrams created during the inference processes.

The focus of this work is on the interactions among (possibly heterogeneous) agents that form an open society, and on the definition of a computational logic-based architecture for agent interaction. We propose a model where the society defines the allowed interaction protocols, which determine the ``socially'' allowed agent interaction patterns. The semantics of protocols can be defined by means of social integrity constraints. The main advantages of this approach are in the design of societies of agents, and in the possibility to detect undesirable behavior. In the paper, we present the model for societies ruled by protocols expressed as integrity constraints, and its declarative semantics. A sketch of the operational counterpart is also given

Although stemming from very different research areas, MultiAgent Systems (MAS) and Service Oriented Computing (SOC) share common topics, problems and settings. One of the common problems is the need to formally verify the conformance of individuals (Agents or Web Services) to common rules and specifications (resp. Protocols/Choreographies), in order to provide a coherent behaviour and to reach the goals of the user.In previous publications, we developed a framework, SCIFF, for the automatic verification of compliance of agents to protocols. The framework includes a language based on abductive logic programming and on constraint logic programming for formally defining the social rules; suitable proof-procedures to check on-the-fly and a-priori the compliance of agents to protocols have been defined.Building on our experience in the MAS area, in this paper we make a first step towards the formal verification of web services conformance to choreographies. We adapt the SCIFF framework for the new settings, and propose a heir of SCIFF, the framework A l LoWS (Abductive Logic Web-service Specification). A l LoWS comes with a language for defining formally a choreography and a web service specification. As its ancestor, A l LoWS has a declarative and an operational semantics. We show examples of how A l LoWS deals correctly with interaction patterns previously identified. Moreover, thanks to its constraint-based semantics, A l LoWS deals seamlessly with other cases involving constraints and deadlines.