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In the past, logics of several kinds have been proposed for reasoning about discrete-time or continuous-time Markov chains. Most of these logics rely on either state labels (atomic propositions) or on transition labels (actions). However, in several applications it is useful to reason about both state properties and action sequences. For this purpose, we(More)
This paper describes the tool CASPA, a new performance evaluation tool which is based on a Markovian stochastic process algebra. CASPA uses multi-terminal binary decision diagrams (MTBDD) to represent the labelled continuous time Markov chain (CTMC) underlying a given process algebraic specification. All phases of modelling, from model construction to(More)
—Failure mode and effects analysis (FMEA) is a technique to reason about possible system hazards that result from system or system component failures. Traditionally , FMEA does not take the probabilities with which these failures may occur into account. Recently, this shortcoming was addressed by integrating stochastic model checking techniques into the(More)
This paper proposes a formally well-rooted and extensible framework for dependability evaluation: Arcade (architectural dependability evaluation). It has been designed to combine the strengths of previous approaches to the evaluation of dependability. A key feature is its formal semantics in terms of input/output-interactive Markov chains, which enables(More)
In this paper we introduce the logic asCSL, an extension of continuous stochastic logic (CSL), which provides powerful means to characterise execution paths of action-and state-labelled Markov chains. In asCSL, path properties are characterised by regular expressions over actions and state-formulas. Thus, the executability of a path not only depends on the(More)
Probabilistic Model Checking is an established technique used in the dependability analysis of safety-critical systems. In recent years, several approaches to generate probabilistic counterexamples have been proposed. The interpretation of stochastic counterexamples, however , continues to be problematic since they have to be represented as sets of paths,(More)
A new denotational semantics for a variant of the stochastic process algebra TIPP is presented, which maps process terms to Multi-terminal binary decision diagrams. It is shown that the new semantics is Markovian bisimulation equivalent to the standard SOS semantics. The paper also addresses the difficult question of keeping the underlying state space(More)