A counter abstraction technique for the verification of robot swarms.

We study parameterised verification of robot swarms against temporal-epistemic specifications. We relax some of the significant restrictions assumed in the literature and present a counter abstraction approach that enable us to verify a potentially much smaller abstract model when checking a formula on a swarm of any size. We present an implementation and discuss experimental results obtained for the alpha algorithm for robot swarms

Model Checking Unbounded Artifact-Centric Systems

Copyright © 2014, Association for the Advancement of Artificial Intelligence (www.aaai.org). All rights reserved.Artifact-centric systems are a recent paradigm for representing and implementing business processes. We present further results on the verification problem of artifact-centric systems specified by means of FO-CTL specifications. While the general problem is known to be undecidable, results in the literature prove decidability for artifact systems with infinite domains under boundedness and conditions such as uniformity. We here follow a different approach and investigate the general case with infinite domains. We show decidability of the model checking problem for the class of artifact-centric systems whose database schemas consist of a single unary relation, and we show that that the problem is undecidable if artifact systems are defined by using one binary relation or two unary relations

Verifying and Synthesising Multi-Agent Systems against One-Goal Strategy Logic Specifications

© Copyright 2015, Association for the Advancement of Artificial Intelligence (www.aaa1.org). All rights reserved.Strategy Logic (SL) has recently come to the fore as a useful specification language to reason about multi-agent systems. Its one-goal fragment, or SL[1g], is of particular interest as it strictly subsumes widely used logics such as ATL∗, while maintaining attractive complexity features. In this paper we put forward an automata-based methodology for verifying and synthesising multi-agent systems against specifications given in SL[Ig], We show that the algorithm is sound and optimal from a computational point of view. A key feature of the approach is that all data structures and operations on them can be performed on BDDs. We report on a BDD-based model checker implementing the algorithm and evaluate its performance on the fair process scheduler synthesis

Reachability analysis for neural agent-environment systems

We develop a novel model for studying agent-environment systems, where the agents are implemented via feed-forward ReLU neural networks. We provide a semantics and develop a method to verify automatically that no unwanted states are reached by the system during its evolution. We study several reachability problems for the system, ranging from one-step reachability, to fixed multi-step and arbitrary-step to study the system evolution. We also study the decision problem of whether an agent, realised via feed-forward ReLU networks will perform an action in a system run. Whenever possible, we give tight complexity bounds to decision problems intro- duced. We automate the various reachability problems stud- ied by recasting them as mixed-integer linear programming problems. We present an implementation and discuss the ex- perimental results obtained on a range of test cases

An abstraction technique for the verification of multi-agent systems against ATL specifications

Copyright © 2014, Association for the Advancement of Artificial Intelligence (www.aaai.org). All rights reserved.We introduce an abstraction methodology for the verification of multi-agent systems against specifications expressed in alternating-time temporal logic (ATL). Inspired by methodologies such as predicate abstraction, we define a three-valued semantics for the interpretation of ATL formulas on concurrent game structures and compare it to the standard two-valued semantics. We define abstract models and establish preservation results on the three-valued semantics between abstract models and their concrete counterparts. We illustrate the methodology on the large state spaces resulting from a card game

Approximating perfect recall when model checking strategic abilities

We investigate the notion of bounded recall in the context of model checking ATL ∗ and ATL specifications in multi- agent systems with imperfect information. We present a novel three-valued semantics for ATL ∗ , respectively ATL , under bounded recall and imperfect information, and study the cor- responding model checking problems. Most importantly, we show that the three-valued semantics constitutes an approxi- mation with respect to the traditional two-valued semantics. In the light of this we construct a sound, albeit partial, al- gorithm for model checking two-valued perfect recall via its approximation as three-valued bounded recall

Combining fault injection and model checking to verify fault tolerance, recoverability, and diagnosability in multi-agent systems

We present an automated technique that combines fault injection with model checking to verify fault tolerance, recoverability, and diagnosability in multi-agent systems. We define a general method for mutating a multi-agent systems model representing correct behaviour by injecting faults into it, and specification patterns based on temporal-epistemic formulas to reason about the correct and faulty behaviours of the mutated model. The technique is implemented in a toolkit that can be used for injecting automatically faults into a multi-agent systems program. The usefulness of the methodology is demonstrated by injecting a number of faults into a model of the IEEE 802.5 token ring LAN protocol and analysing the protocol's fault tolerance, by verifying a number of temporal-epistemic specifications