Simulations of very early life cycle quality evaluation : the softgoal simulation tool

The purpose of this research was to develop a tool for quality estimation and decision making during very early life cycle of software system, when data is scarce and information is unavailable. This thesis begins with the introduction and related work chapters, which identifies the problems with achieving quality software and the current state-of-the-art of system modeling and simulation. Then, the requirement analysis technique proposed in this paper is presented: first, a model is needed to capture the tradeoffs/synergy between software quality attributes and applicable design alternatives. We have adopted the softgoal framework by Chung, Nixon, Yu and Mylopoulous [28] in modeling such knowledge for analysis. Second, an inference engine is built to automatically execute the text-encoded softgoal framework. Thirdly, we incorporate Monte Carlo simulation to explore the wide range of behaviors in the model, and summarize these behaviors with a treatment-learning tool named TAR2. Five case studies have been presented through chapter 3 to chapter 8 to demonstrate the usage of the Softgoal Simulation Tool to model and simulate various systems. This thesis concludes with a summary of research results, contributions to the related software engineering field, and further research directions.Applied Science, Faculty ofElectrical and Computer Engineering, Department ofGraduat