The refinement calculus for logic programs is a framework for deriving logic programs from specifications. It is based on a wide-spectrum language that can express both specifications and code, and a refinement relation that models the notion of correct implementation. In this paper we extend and generalise earlier work on contextual refinement. Contextual refinement simplifies the refinement p...

This paper presents the methodology for the system requirements and architecture w.r.t. their decomposition and refinement. It also introduces ideas of refinement layers and of refinement-based verification.

This paper presents an automated tool for local, conformal refinement of all-hexahedral meshes based on the insertion of multidirectional twist planes into the spatial twist continuum. The refinement process is divided into independent refinement steps. In each step, an inserted twist plane modifies a single sheet or two parallel hex sheets. Six basic templates, chosen and oriented based on the...

In this contribution a generalized spectral refinement method of speech signals will be presented which can either be applied at a preprocessing stage before or at a postprocessing stage after a conventional frequency analysis. The refinement approach is based on a linear combination of weighted and shifted input speech signal segments. By applying the refinement method either in time or in the...

In recent years compliance has emerged as one of the big IT challenges enterprises are faced with. The management of a multitude of regulations and the complexity of current business processes are problems that need to be addressed. In this paper we present an approach based on so-called compliance templates to develop and manage compliant business processes involving different stakeholders. We...

We study refinement in the setting of local reasoning. In particular, we explore general translations that preserve and that break locality.

Stepwise refinement (SWR) is fundamental to software engineering. As aspect-oriented programming (AOP) gains momentum in software development, aspects should be subject to SWR as well. In this paper, we introduce the notion of aspect refinement that unifies AOP and SWR. To reflect this unification to programming language level, we present an implementation technique for refining aspects based o...

Refinement tools such as compilers do not necessarily preserve fault-tolerance. That is, given a fault-tolerant program in a high-level language as input, the output of a compiler in a lower-level language will not necessarily be faulttolerant. In this paper, we identify a type of refinement, namely “convergence refinement”, that preserves the faulttolerance property of stabilization. We illust...

In this paper we discuss the refinement of exceptions. We extend the Guarded Command Language normally used in the refinement calculus, with a simple exception handling statement, which we model using King and Morgan’s exit statement. We derive some variants of King and Morgan’s refinement laws for their exit statement, and illustrate the approach with an example of a refinement of a simple pro...

Refinement plays a crucial role in “top-down” styles of verification, such as the refinement calculus, but for probabilistic systems proof of refinement is a particularly challenging task due to the combination of probability and nondeterminism which typically arises in partiallyspecified systems. Whilst the theory of probabilistic refinement is well-known [19] there are few tools to help with ...