Verification of embedded systems has become increasingly important in many industrial domains. Safetycritical embedded systems, such as those developed in aerospace industry, are regularly subject to automated formal verification process. In this paper we extend our tool integration chain of parallel, explicit-state LTL model checker DIVINE and Matlab Simulink tool suit with an improved support of counterexample simulation. In particular, we show how to provide the verification engineer with a direct connection between the error discovered by the model checker and the simulation in Matlab Simulink. This work has been conducted within the Artemis project industrial Framework for Embedded Systems Tools (iFEST).

This paper presents a study on how cooperation versus non-cooperation, and centralization versus distribution impact the performance of a traffic game of autonomous vehicles. A model using a particle-based, Lagrange representation, is developed, instead of a Eulerian, flow-based one, usual in routing problems of the game-theoretical approach. This choice allows representation of phenomena such as fuel exhaustion, vehicle collision, and wave propagation. The elements necessary to represent interactions in a multi-agent transportation system are defined, including a distributed, priority-based resource allocation protocol, where resources are nodes and links in a spatial network and individual routing strategies are performed. A fuel consumption dynamics is developed in order to account for energy cost and vehicles having limited range.The analysis shows that only the scenarios with cooperative resource allocation can achieve optimal values of either collective cost or equity coefficient, corresponding respectively to the centralized and to the distributed cases.

The safety in the airspace can considerably increase with the use of airborne spacing and separation operations. Under this paradigm, the task of maintaining a safe distance between aircraft is delegated to the pilots, which will be supported by the Airborne Separation Assistance System (ASAS). With this system, which is still in experimental phase, pilots become aware of the surrounding air traffic risks with up to 15 minutes in advance, without the help of air traffic controllers on the ground. This antecedence is much greater than the one provided by the current Traffic Collision Avoidance System (TCAS). ASAS uses a more advanced communication technology than Mode-C transponder, broadly used in the current civil aviation for collision avoidance purposes. The development of ASAS is being carried out intensively in Eurocontrol and in other initiatives in the United States of America, and this novel system is intended to work in parallel with the current collision avoidance systems, acting as safety nets. The present study approaches the ASAS application to improve the precision of spacing between aircraft that sequentially arrive at an airport, using the so called mathematical formalism "Stochastically and Dynamically Coloured Petri Net", for evaluating quantitative data about accident risk. These data indicate that the accident risk is significantly smaller when aircraft pairs use ASAS Spacing than when aircraft pairs do not use ASAS Spacing.

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