Shared Semantic Domains for Computational Reliability Engineering

Modeling languages and the software tools which support them are essential to engineering. However, as these languages become more sophisticated, it becomes difficult to assure both the validity of their semantic specifications and the dependability of their program implementations. To ameliorate this problem we propose to develop shared semantic domains and corresponding implementations for families of related modeling languages. The idea is to amortize investments at the intermediate level across multiple language definitions and implementations. To assess the practicality of this approach for modeling languages, we applied it to two languages for reliability modeling and analysis. In earlier work, we developed the intermediate semantic domain of failure automata (FA), which we used to formalize the semantics of dynamic fault trees (DFTs). In this paper, we show that a variant of the original FA can serve as a common semantic domain for both DFTs and reliability block diagrams (RBDs). Our experiences suggest that the use of a common semantic domain and a shared analyzer for expressions at this level can ease the task of formalizing and implementing modeling languages, reducing development costs and improving their dependability.