Thomas Eiter

Logic Programming and Nonmotonic Reasoning

I report about a particular approach to heterogenous agent systems, IMPACT, which is strongly related to computational logic. The underlying methods and techniques stem from both non-monotonic reasoning and logic programming. I present three recent extensions to illustrate the generality and usefulness of the approach: (1) incorporating planning, (2) uncertain (probabilistic) reasoning, and (3) reducing the load of serving multiple requests. While (1) illustrates how easy it is to incorporate hierachical task networks into IMPACT, (2) makes heavily use of annotated logic programming and (3) is strongly related to classical first-order reasoning. This paper is a high-level description of (1)–(3), More detailed expositions can be found in [1,2,3,4] from which most parts of this paper are taken. 1 The Basic Framework The IMPACT project (http://www.cs.umd.edu/projects/impact) aims at developing a powerful multi agent system, which (1) is able to deal with heterogenous and distributed data, (2) can be realized on top of arbitrary legacy code, but yet (3) is built on a clear foundational bases and (4) scales up for realistic applications. In this article I am pointing to some recent extensions of the basic framework (which has been implemented and is running) that show very clearly the strong links to computational logic, even though IMPACT’s implementation is not realized on top of a logic related procedural mechanism. To get a bird’s eye view of IMPACT, here are the most important features: – Each IMPACT agent has certain actions available. Agents act in their environment according to their agent program and a well defined semantics determining which of the actions the agent should execute. – Each agent continually undergoes the following cycle: The work I am reporting has been done with many colleagues, notably Th. Eiter, S. Kraus, K. Munoz-Avila, M. Nanni, D. Nau, F. Özcan, T.J. Rogers, R. Ross and, last but not least, V.S Subrahmanian. It resulted in a variety of papers and I gratefully acknowledge their support. T. Eiter, W. Faber, and M. Truszczyński (Eds.): LPNMR 2001, LNAI 2173, pp. 1–21, 2001. c

Advances in Knowledge Representation, Logic Programming, and Abstract Argumentation

This Festschrift is published in honor of Gerhard Brewka on the occasion of his 60th birthday and contains articles from fields reflecting the breadth of Gerds work. The 24 scientific papers included in the book are written by close friends and colleagues and cover topics such as Actions and Agents, Nonmonotonic and Human Reasoning, Preferences and Argumentation.