| Reasoning about the evolvability properties and economic implications of design structures is critical to high-consequence decision-making, but it remains difficult. One key impediment is the lack of analyzable high-level design representations that both convey design architectures and enable designers to reason precisely about their modularity properties and economics. This dissertation contributes such a formal and analyzable representation. It supports formal design modeling and enables automation of a number of evolvability and economic-related analyses.;We model both design decisions and relevant external conditions using an augmented form of constraint networks (ACNs). To support design impact analysis, we derive an intermediate, state-machine-based design space model from an ACN, which we call a design automaton (DA). To support traditional design coupling structure analysis, we derive a pair-wise dependence relation (PWDR) from a DA, based on which we can then derive design structure matrices (DSMs) to make use of a number of existing economic and engineering analysis techniques. We created a divide-and-conquer approach to addressing scalability issues in constraint solving and solution enumeration that a DA requires. We extend the ACN model into the complex augmented constraint network (CACN) to support the modeling and analysis of design decisions with structural impacts.;This dissertation provides evidence to support the following thesis: this framework formally accounts for the key concepts of important but informal theories, enables automation of a range of formal architectural analysis methods related to evolution and economic value, and generalizes to provide an account of both object-oriented and newer aspect-oriented notions of modularity in a unified, declarative framework. |
