Desiree: a Refinement Calculus for Requirements Problems
This addresses the requirements engineering problem for software developers and stakeholders, but it appears incremental as it builds on existing refinement calculus approaches.
The paper tackles the problem of transforming informal, incomplete, ambiguous, and inconsistent stakeholder requirements into a formal, complete, unambiguous, consistent, modifiable, and traceable specification by proposing Desiree, a refinement calculus. It defines semantics for concepts and operators, presents a graphical modeling tool, and illustrates reasoning tasks with a Meeting Scheduler example.
The requirements elicited from stakeholders are typically informal, incomplete, ambiguous, and inconsistent. It is the task of Requirements Engineering to transform them into an eligible (formal, sufficiently complete, unambiguous, consistent, modifiable and traceable) requirements specification of functions and qualities that the system-to-be needs to operationalize. To address this requirements problem, we have proposed Desiree, a requirements calculus for systematically transforming stakeholder requirements into an eligible specification. In this paper, we define the semantics of the concepts used to model requirements, and that of the operators used to refine and operationalize requirements. We present a graphical modeling tool that supports the entire framework, including the nine concepts, eight operators and the transformation methodology. We use a Meeting Scheduler example to illustrate the kinds of reasoning tasks that we can perform based on the given semantics.