Modularity and Openness in Modeling Multi-Agent Systems

We revisit the formalism of modular interpreted systems (MIS) which encourages modular and open modeling of synchronous multi-agent systems. The original formulation of MIS did not live entirely up to its promise. In this paper, we propose how to improve modularity and openness of MIS by changing the structure of interference functions. These relatively small changes allow for surprisingly high flexibility when modeling actual multi-agent systems. We demonstrate this on two well-known examples, namely the trains, tunnel and controller, and the dining cryptographers. Perhaps more importantly, we propose how the notions of multi-agency and openness, crucial for multi-agent systems, can be precisely defined based on their MIS representations.Comment: In Proceedings GandALF 2013, arXiv:1307.416

Bounded Model Checking for Linear Time Temporal-Epistemic Logic

We present a novel approach to the verification of multi-agent systems using bounded model checking for specifications in LTLK, a linear time temporal-epistemic logic. The method is based on binary decision diagrams rather than the standard conversion to Boolean satisfiability. We apply the approach to two classes of interpreted systems: the standard, synchronous semantics and the interleaved semantics. We provide a symbolic algorithm for the verification of LTLK over models of multi-agent systems and evaluate its implementation against MCK, a competing model checker for knowledge. Our evaluation indicates that the interleaved semantics can often be preferable in the verification of LTLK

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Reachability Analysis for Timed Automata Using Partitioning Algorithms

The paper presents a new method for checking reachability properties of Timed Automata. The ide

Reachability Analysis for Timed Automata Based on Partitioning

Model checking is an approach commonly applied for automated veri cation of reachability properties. Given a system S and a property p, reachability model checking consists in an exploration of the state space of S, checking whether there exists a state where p holds. Since concrete state spaces (models) of timed systems are usually in nite, they cannot be directly applied to model checking. One of the solution to this problem is to exploit nite abstract models, preseving the properties of interest. The paper presents a new method of buildng abstract models for Timed Automata, based on a partitioning algorithm. Our pseudo-bisimulating models are often smaller than forward-reachability graphs, commonly used in reachability analysis. The method enables veri cation on-the-y, i.e., generating of the model can be stopped as soon as a state satisfying p is found