Catálogo de publicaciones - libros

This paper develops a semantic framework for interpreting heterogeneous system specifications consisting of a mixture of scenario-based requirements and state-based design. Such specifications arise naturally in spiral- and refinement-based development methodologies in which parts of a system have detailed designs while others exist in more abstract form as a collection of requirements. More precisely, we consider the scenario-based notation of Triggered Message Sequence Charts (TMSCs) and the state-based notation of Communicating State Machines (CSMs), and show how they may be integrated in a semantic framework that is founded on the mathematical theory of acceptance trees. Our semantic theory is also equipped with a robust notion of refinement, which allows us to relate one heterogeneous specification with another. A case-study serves to illustrate the utility of our framework as a basis for the principled evolution of higher-level requirements to lower-level operational specifications.

We present the notion of consistency relation in UML and B multi-view specifications. It is defined as a semantic relation between both views. It provides us with a sound basis to define the notion of development operator. An operator models a development step; it separates the design decisions from their expression in the specification formalisms. Operator correctness is defined as a property which guarantees that the application of an operator on a consistent specification state yields a consistent new state. An operator can be proven once and for all to be correct. A classical case-study, the Generalized Railroad Crossing (GRC), demonstrates how the different notions can be put in practice to provide specifiers with a realistic development model.