Keynote lecture at QEST 2022 (within CONFEST 2022), Warsaw, Poland

I was very happy to be invited as a speaker to QEST since it is a conference in which I have been involved since it origins in 2004, being as author, PC member, PC chair, general chair, SC member, reviewer, or just as participant.

The slides presented here corresponds to the keynote lecture I gave at th 19th International Conference on Quantitative Evaluation of SysTems (QEST 2022), within the framework of CONFEST 2022, which was held in Warsaw, Poland, between the 12th and 16th of September 2022.

The talk described the work we have done with Carlos E. Budde and Raúl E. Monti which lately also included Mariëlle Stoelinga.

Title: Analysis of Highly Reliable Repairable Fault Trees via Simulation.
Abstract: Dynamic fault trees (DFTs) are widely adopted in industry to assess the dependability of safety-critical equipment. Since many systems are too large to be studied numerically, DFTs dependability is often analyzed using Monte Carlo simulation. A bottleneck here is that many simulation samples are required in the case of rare events, e.g. in highly reliable systems where components seldom fail. Rare event simulation (RES) provides techniques to reduce the number of samples in the case of rare events. In this talk, I will present the theory that leads to the implementation of an importance splitting based toolchain to simulate a variant of repairable fault trees (RFT) whose stochastic behaviour includes non-Markovian continuous distribution. The semantics of RFT is formally defined in a compositional way in terms of input/output stochastic automata, ensuring that the resulting object is amenable to simulation. Moreover, RES requires meta-information that is usually provided by an expert. Instead, we provide a fully automatic way to derive such necessary data.