A. Saeed
R. de Lemos
T. Anderson
University of Newcastle upon Tyne. 1993
Requirements analysis plays a vital role in software development, since defective requirements specifications may introduce faults during subsequent phases of software development which can lead to accidents. In this paper we discuss a methodology, based on formal notations, to support requirements analysis for safety-critical systems. The proposed methodology consists of a framework whose phases are based on levels of abstraction which follow from a general structure for process control systems, a set of notations appropriate for the issues to be analysed at each phase of the framework, and a hierarchical structure for the product of the analysis. The intention is to locate and remove faults during the requirements phase, rather than later in development during the operational lifetime of the system. Some aspects of the methodology are illustrated using an example based on a nuclear reactor system.