Catálogo de publicaciones - libros

HTN planning, especially forward-chaining HTN planning, is becoming important in the areas of agents and robotics, which have to deal with the dynamically changing world. Therefore, replanning in “forward-chaining” HTN planning has become an important subject for future study. This paper presents the new agent algorithm that integrates forward-chaining HTN planning, execution, belief updates, and plan modifications. Also, through combination with an A*-like heuristic search strategy, we show that our agent algorithm is effective for the replanning problem of museum tour guide robots, which is similar to the replanning problem of a traveling salesman.

Logics for knowledge and time comprise logic combinations between epistemic logic S 5_ n for n agents and temporal logic. In this paper we examine a logic combination of Computational Tree Logic and an epistemic logic augmented to include an additional epistemic operator representing explicit knowledge. We show the resulting system enjoys the finite model property, decidability and is finitely axiomatisable. It is further shown that the expressivity of the resulting system enables us to represent a non-standard notion of deductive knowledge which seems promising for applications.

We explore the suitability of Intensional Programming Paradigm for providing a programming model for coordinated problem solving in a multi-agent system. We extend our previous work on Lucx, an Intensional Programming Language extended with context as first class object, to support coordination activities in a distributed network of agents. We study coordination constructs which can be applied to sequential programs and distributed transactions. We give formal syntax and semantics for coordination constructs. The semantics for transaction expressions is given on top of the existing operational semantics in Lucx. The extended Lucx can be used for Internet-based agent applications.

In this paper, we propose a new tableau-based model checking technique for verifying dialogue game protocols for agent communication. These protocols are defined using our social commitment-based framework for agent communication called Commitment and Argument Network (CAN). We use a variant of CTL* (ACTL*) for specifying these protocols and the properties to be verified. This logic extends CTL* by allowing formulae to constrain actions as well as states. The verification method is based on the translation of formulae into a variant of alternating tree automata called Alternating Büchi Tableau Automata (ABTA). We propose a set of tableau rules (inference rules) for specifying this translation procedure. Unlike the model checking algorithms proposed in the literature, the algorithm that we propose in this paper allows us not only to verify if the dialogue game protocol (the model) satisfies a given property, but also if this protocol respects the tableau rules-based decomposition of the action formulae. This algorithm is an on-the-fly efficient algorithm.