Strategies Resilient to Delay: Games under Delayed Control vs. Delay Games (full version)

We compare games under delayed control and delay games, two types of infinite games modelling asynchronicity in reactive synthesis. Our main result, the interreducibility of the existence of sure winning strategies for the protagonist, allows to transfer known complexity results and bounds on the delay from delay games to games under delayed control, for which no such results had been known. We furthermore analyze existence of randomized strategies that win almost surely, where this correspondence between the two types of games breaks down

Strategies Resilient to Delay:Games under Delayed Control vs. Delay Games

We compare games under delayed control and delay games, two types of infinite games modelling asynchronicity in reactive synthesis. Our main result, the interreducibility of the existence of sure winning strategies for the protagonist, allows to transfer known complexity results and bounds on the delay from delay games to games under delayed control, for which no such results had been known. We furthermore analyze existence of randomized strategies that win almost surely, where this correspondence between the two types of games breaks down.</p

Analysis of hybrid systems using HySAT

In this paper we describe the complete workflow of analyzing the dynamic behavior of safety-critical embedded systems with HySAT. HySAT is an arithmetic constraint solver with a tightly integrated bounded model checker for hybrid discrete-continuous systems which — in contrast to many other solvers — is not confined to linear arithmetic, but can also deal with nonlinear constraints involving transcendental functions. Based on a controller for train separation implementing a “moving block ” interlocking scheme in the forthcoming European Train Control System Level 3, we exemplify the usage of the tool over the whole cycle from encoding a hybrid system to interpreting the results

Verification of Sigmoidal Artificial Neural Networks using iSAT

This paper presents an approach for verifying the behaviour of nonlinear Artificial Neural Networks (ANNs) found in cyber-physical safety-critical systems. We implement a dedicated interval constraint propagator for the sigmoid function into the SMT solver iSAT and compare this approach with a compositional approach encoding the sigmoid function by basic arithmetic features available in iSAT and an approximating approach. Our experimental results show that the dedicated and the compositional approach clearly outperform the approximating approach. Throughout all our benchmarks, the dedicated approach showed an equal or better performance compared to the compositional approach.Comment: In Proceedings SNR 2021, arXiv:2207.0439

Estimating the Probability of a Timely Traffic-Hazard Warning via Simulation

Abstract Traffic flow simulation is exploited for estimating the probability that a message -a hazard warning in this caseis correctly transmitted to an approaching car in time, that is, before overstepping a safety threshold. The results derived by simulation provide valuable insights in the functional relation between the numerous authoritative parameters and the reliability of timely message reception