Logic-Based Specification Languages for Intelligent Software Agents

The research field of Agent-Oriented Software Engineering (AOSE) aims to find abstractions, languages, methodologies and toolkits for modeling, verifying, validating and prototyping complex applications conceptualized as Multiagent Systems (MASs). A very lively research sub-field studies how formal methods can be used for AOSE. This paper presents a detailed survey of six logic-based executable agent specification languages that have been chosen for their potential to be integrated in our ARPEGGIO project, an open framework for specifying and prototyping a MAS. The six languages are ConGoLog, Agent-0, the IMPACT agent programming language, DyLog, Concurrent METATEM and Ehhf. For each executable language, the logic foundations are described and an example of use is shown. A comparison of the six languages and a survey of similar approaches complete the paper, together with considerations of the advantages of using logic-based languages in MAS modeling and prototyping.Comment: 67 pages, 1 table, 1 figure. Accepted for publication by the Journal "Theory and Practice of Logic Programming", volume 4, Maurice Bruynooghe Editor-in-Chie

Logical Judges Challenge Human Judges on the Strange Case of B.C.-Valjean

On May 12th, 2020, during the course entitled Artificial Intelligence and Jurisdiction Practice organized by the Italian School of Magistracy, more than 70 magistrates followed our demonstration of a Prolog logical judge reasoning on an armed robbery case. Although the implemented logical judge is just an exercise of knowledge representation and simple deductive reasoning, a practical demonstration of an automated reasoning tool to such a large audience of potential end-users represents a first and unique attempt in Italy and, to the best of our knowledge, in the international panorama. In this paper we present the case addressed by the logical judge - a real case already addressed by a human judge in 2015 - and the feedback on the demonstration collected from the attendees

Agents interoperability via conformance modulo mapping

We present an algorithm for establishing a flexible conformance relation between two local agent interaction protocols (LAIPs) based on mappings involving agents and messages, respectively. Conformance is in fact computed "modulo mapping": two LAIPs \u3c4 and \u3c4 may involve different agents and use different syntax for messages, but may still be found to be conformant provided that a given map from entities appearing in \u3c4 to corresponding entities in \u3c4 is applied. LAIPs are modelled as trace expressions whose high expressive power allows for the design of protocols that could not be specified using finite state automata or equivalent formalisms. This expressive power makes the problem of stating if \u3c4 conforms to \u3c4 undecidable. We cope with this problem by over-approximating trace expressions that may lead to infinite computations, obtaining a sound but not complete implementation of the proposed conformance check

Decentralizing MAS Monitoring with DecAMon

We describe DecAMon, an algorithm for decentralizing the monitoring of the MAS communicative behavior described via an Agent Interaction Protocol (AIP). If some agents in the MAS are grouped together and monitored by the same monitor, instead of individually, a partial decentralization of the monitoring activity can still be obtained even if the "unique point of choice" (a.k.a. local choice) and "connectedness for sequence" (a.k.a. causality) coherence conditions are not satisfied by the protocol. Given an AIP specification, DecAMon outputs a set of "Monitoring Safe Partitions" of the agents, namely partitions P which ensure that having one monitor in charge for each group of agents in P allows detection of all and only the protocol violations that a fully centralized monitor would detect. In order to specify AIPs we use "trace expressions": this formalism can express event traces that are not context-free and can model both synchronous and asynchronous communication just by changing the underlying notion of event

OntologyBeanGenerator 5.0: Extending ontology concepts with methods and exceptions

When modeling and implementing complex systems based on agents and artifacts, achieving semantic interoperability is not only useful, but often necessary. A commonly adopted solution to manage complex and real MASs is adopting a Model Driven methodology, which uses an ontology as the formal representation of the domain, and then exploiting some existing tool to automatically generate code for agents in the MAS, to let them interact according to the model. While this approach is satisfactorily supported when the target MAS environment is Jason, less support is provided to Jade MASs, despite Jade's large adoption for real MASs development. So, considering the great support given by the automatic code generation starting from a formal model, and the large community working on Jade MASs, in this work we present an extension of the OntologyBeanGenerator plugin for Prot\ue9g\ue9, used to generate a Java representation of an OWL ontology for Jade. We improved the OntologyBeanGenerator tool to support the modeling of exceptions, formalized at the ontology level, and of methods associated with ontology elements, to set the interface of concrete objects (artifacts) at design stage. This extension allows us to integrate in a Model Driven approach a support for the formal definition of artifacts and provide an automatic generation of Jade code/interfaces to interact with them respecting the model

Logic-based Technologies for Multi-agent Systems: A Systematic Literature Review

Precisely when the success of artificial intelligence (AI) sub-symbolic techniques makes them be identified with the whole AI by many non-computerscientists and non-technical media, symbolic approaches are getting more and more attention as those that could make AI amenable to human understanding. Given the recurring cycles in the AI history, we expect that a revamp of technologies often tagged as “classical AI” – in particular, logic-based ones will take place in the next few years. On the other hand, agents and multi-agent systems (MAS) have been at the core of the design of intelligent systems since their very beginning, and their long-term connection with logic-based technologies, which characterised their early days, might open new ways to engineer explainable intelligent systems. This is why understanding the current status of logic-based technologies for MAS is nowadays of paramount importance. Accordingly, this paper aims at providing a comprehensive view of those technologies by making them the subject of a systematic literature review (SLR). The resulting technologies are discussed and evaluated from two different perspectives: the MAS and the logic-based ones

Logic-based Technologies for Multi-agent Systems: Summary of a Systematic Literature Review

The paper summarises a systematic literature review (SLR) over logic-based technologies for MAS