We describe a method for synthesizing reasonable underapproximations to weakest preconditions for termination—a long-standing open problem. The paper provides experimental evidence to demonstrate the usefulness of the new procedure.

Being one of the most expensive components of an electrical power plant, the failures of a power transformer can result in serious power system issues. So fault diagnosis for power transformer is highly important to ensure an uninterrupted power supply. Due to information transmission mistakes as well as arisen errors while processing data in surveying and monitoring state information of transf...

where b ranges over a set BExp of boolean expressions, a ranges over a set Act of basic actions and p is a real number with 0 < p < 1. We write cond(b, P,Q) for the conditional usually denoted as if b then P else Q fi and while(b, P ) for the while loop usually denoted as while b do P od The program P8Q nondeterministically executes either P or Q. The program P p⊕Q executes P with probability p...

In 1979, Cousot and Cousot gave a specification of the “best” (most-precise) abstract transformer possible for a given concrete transformer and a given abstract domain. Unfortunately, their specification does not lead to an algorithm for obtaining best transformers. In fact, algorithms are known for only a few abstract domains. This paper presents a parametric framework that, for some abstract ...

This paper studies the model theory as generalization of classical model theory in predicate fuzzy logic with evaluated syntax (Ev L ). There exist a lot of possibilities how to find the models of fuzzy theories. In this paper we will describe the theoretic constructions of the models in Ev L where these models are built by using elementary extensions and downward Löwenheim-Skolem-Tarski theore...

Weak omega algebra and demonic refinement algebra are two ways of describing systems with finite and infinite iteration. We show that these independently introduced kinds of algebras can actually be defined in terms of each other. By defining modal operators on the underlying weak semiring, that result directly gives a demonic refinement algebra of commands. This yields models in which extensio...

G. Plotkin and the author [13] have worked out the equivalence between state transformer semantics and predicate transformer semantics in a domain theoretical setting for programs combining nondeterminism and probability. Works of C. Morgan and co-authors [20], Keimel, Rosenbusch and Streicher [14, 15], already go in the same direction using only discrete state spaces. In fact, Keimel and Plotk...