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We describe the main features of S m A r T, a software package providing a seamless environment for the logic and probabilistic analysis of complex systems. S m A r T can combine different formalisms in the same modeling study. For the analysis of logical behavior, both explicit and symbolic state-space generation techniques, as well as symbolic CTL(More)
We present a novel algorithm for generating state spaces of asynchronous systems using Multi–valued Decision Diagrams. In contrast to related work, we encode the next–state function of a system not as a single Boolean function, but as cross–products of integer functions. This permits the application of various iteration strategies to build a system's state(More)
Many state-of-the-art techniques for the veriication of today's complex embedded systems rely on the analysis of their reachable state spaces. In this paper, we develop a new algorithm for the symbolic generation of the state space of asynchronous system models, such a s P etri nets. The algorithm is based on previous work that employs Multi-valued D e(More)
We describe an algebra of Edge-Valued Decision Diagrams (EVMDDs) to encode arithmetic functions and its implementation in a model checking library. We provide efficient algorithms for manipulating EVMDDs and review the theoretical time complexity of these algorithms for all basic arithmetic and relational operators. We also demonstrate that the time(More)
We investigate a new class of metrics to find good variable orders for decision diagrams in symbolic state-space generation. Most of the previous work on static ordering is centered around the concept of minimum variable span, which can also be found in the literature under several other names. We use a similar concept, but applied to event span, and(More)
Symbolic state-space generators are notoriously hard to par-allelise. However, the Saturation algorithm implemented in the SMART verification tool differs from other sequential symbolic state-space generators in that it exploits the locality of firing events in asynchronous system models. This paper explores whether event locality can be utilised to(More)
The Plan Execution Interchange Language (PLEXIL) is an open source synchronous language developed by NASA for commanding and monitoring autonomous systems. This paper reports the development of the PLEXIL's Formal Interactive Verification Environment (PLEXIL5), a graphical interface to the formal executable semantics of PLEXIL. Among its main features,(More)
We present a new method for the symbolic construction of shortest paths in reachability graphs. Our algorithm relies on a variant of edge–valued decision diagrams that supports efficient fixed–point iterations for the joint computation of both the reachable states and their distance from the initial states. Once the distance function is known, a shortest(More)