Multi-agent Systems (MAS) are communities of problem-solving entities that can perceive and act upon their environments to achieve their individual goals as well as joint goals. The work on such systems integrates many technologies and concepts in artificial intelligence and other areas of computing. There is a full spectrum of MAS applications that have been and are being developed; from search engines to educational aids to electronic commerce and trade.
Although commonly implemented by means of imperative languages, mainly for reasons of efficiency, the agent concept has recently increased its influence in the research and development of computational logic based systems.
Computational Logic, by virtue of its nature both in substance and method, provides a well-defined, general, and rigorous framework for systematically studying computation, be it syntax, semantics, procedures, or attending implementations, environments, tools, and standards. Computational Logic approaches problems, and provides solutions, at a sufficient level of abstraction so that they generalise from problem domain to problem domain, afforded by the nature of its very foundation in logic, both in substance and method, which constitutes one of its major assets.
The purpose of this workshop is to discuss techniques, based on computational logic, for representing, programming and reasoning about multi-agent systems in a formal way. This is clearly a major challenge for computational logic, to deal with real world issues and applications.
The first workshop in this series took place in Las Cruces, New Mexico, USA, in 1999, under the designation Multi-Agent Systems in Logic Programming (MASLP'99), and affiliated with ICLP'99. In the following year, the name of the workshop changed to Computational Logic in Multi-Agent Systems (CLIMA'00), taking place in London, UK, and affiliated with CL'2000. The subsequent edition, CLIMA'01, took place in Paphos, Cyprus, affiliated with ICLP'01. The present edition, CLIMA'02, takes place in Copenhagen, Denmark, on August the
1st of 2002, and is affiliated with ICLP'02 and part of FLOC'02.
We would like to thank the authors of the submitted papers, the members of the program committee and the additional reviewers for their contribution to both the meeting and this volume. We would also like to thank Michael Mislove for his help with the editing of the proceedings.
Programme Committee
Jürgen Dix (The University of Manchester, UK)
Thomas Eiter (Vienna University of Technology, Austria)
Klaus Fischer (DFKI, Germany)
Michael Fisher (University of Liverpool, UK)
James Harland (Royal Melbourne Institute of Technology, Australia)
Wiebe van der Hoek (Utrecht University, The Netherlands)
Katsumi Inoue (Kobe University, Japan)
João Alexandre Leite (New University of Lisbon, Portugal)
Luís Moniz Pereira (New University of Lisbon, Portugal)
Ken Satoh (National Institute of Informatics, Japan)
V. S. Subrahmanian (University of Maryland, USA)
Francesca Toni (Imperial College, UK)
Paolo Torroni (University of Bologna, Italy)
Additional Reviewers
For this edition of CLIMA, we have received 25 submissions of which 12 were selected for presentation, after a careful review process where each paper was independently reviewed by three members of the Program Committee.
The workshop consisted of five sessions: four devoted to the oral presentation of the selected papers and subsequent discussion; and one devoted to a panel discussion, Paolo Torroni being the invited moderator. There follows a brief overview of the workshop.
Session 1 - Agents: Arguments and Updates
Schroeder and Schweimeier present a framework based on logic programming with 3-valued multi-agent argumentation and fuzzy unification, for knowledge representation and reasoning in agents, to accommodate arguments for negotiating agents when agent communication is subject to uncertainty.
Leite et al. extend the language LUPS introducing MLUPS, an update command language designed for specifying the flexible evolution of hierarchically related groups of agents, based on logic programming, thus assigning them declarative semantics.
Kakas and Moraïtis present a modular argumentation framework for modelling agent deliberation, where object level arguments can be made conditional on agents' roles and the priority relation amongst such roles can, in turn, be made conditional on contents, on top of which a simple form of abduction allows dealing with incomplete knowledge.
Session 2 - Logics for Agents
Toyama et al. introduce a translation of multi-agent autoepistemic logic (MAEL), a logic for multi-agent systems based on Moore's autoepistemic logic, into logic programming, and show the correspondence between MAEL extensions and the stable models of the corresponding logic program.
Dell'Acqua et al. extend their previous work on abductive logic programming based multi-agent systems, in which agents can update themselves and each other, eliminate contradictory update rules, abduce hypotheses to explain observations, and use them to generate actions, with asynchronous based communication through the use of buffers.
Harland and Winikoff discuss the formalisation and implementation issues of BDI-type agents, using a Linear Logic based calculus that allows a mixture of forward- and backward-chaining techniques.
Session 3 - BDI Agent Systems
Bordini and Moreira investigate how far the Asymmetry Thesis Principles formulated by Rao and Georgeff are actually met by the abstract agent specification language AgentSpeak(L), hence contributing to the reconciliation
Between practice and theory of BDI-based agents.
Araragi et al. formalise and propose a method to solve a verification problem that arises in implementing a commitment strategy for the BDI architecture, namely the verification of the suitability and/or feasibility of the intentions of an agent.
Nide et al. extend with mental state consistency features their previously presented deduction system for CTL-based propositional BDI Logics using sequent calculus, as a step towards the use of the expressive power of BDI Logics as executable specification languages of rational agents.
Session 4 - Agents: Speculative Computation and Introspection
Hayashi et al. address the issue of integrating speculative computation and action execution through logic programming, namely by devising a method for plan modification when speculative computation fails or actions are executed.
Iwanuma and Inoue refine the first-order consequence-finding procedure based on clausal tableaux SOL, with conditional answer computation and skip-preference, to formalise speculative computation in a master-slave multi-agent system.
Bolander investigates on finding consistent classes of formulas under the syntactical treatment of knowledge and belief, identifying three maximal sets of introspective beliefs that strong introspective agents can consistently maintain so as to avoid the paradoxes of self-reference.
Session 5 - Panel Discussion
Torroni moderates a panel discussion entitled ""Logics and Multi-agents: towards a new symbolic model of cognition"".
This volume constitutes the proceedings of CLIMA'02.
September 2002, Jürgen Dix, João Alexandre Leite and Ken Satoh (Guest Editors)