Extension of PRISM by Synthesis of Optimal Timeouts in Fixed-Delay CTMC
  We present a practically appealing extension of the probabilistic model checker PRISM rendering it to handle fixed-delay continuous-time Markov chains (fdCTMCs) with rewards, the equivalent formalism to the deterministic and stochastic Petri nets (DSPNs). fdCTMCs allow transitions with fixed-delays (or timeouts) on top of the traditional transitions with exponential rates. Our extension supports an evaluation of expected reward until reaching a given set of target states. The main contribution is that, considering the fixed-delays as parameters, we implemented a synthesis algorithm that computes the epsilon-optimal values of the fixed-delays minimizing the expected reward. We provide a performance evaluation of the synthesis on practical examples. 
\v{L}ubo\v{s} Koren\v{c}iak, Vojt\v{e}ch \v{R}eh\'ak, Adrian Farmadin
cs.LO cs.PF