Engineering modeling and analysis: sound methods and effective tools

Developing high quality software tools for specialized domains is difficult. One problem is the cost of developing feature-rich and usable tool interfaces. Another problem is the task of providing a sound basis for trustworthiness of the tool and the overall method which it supports. In this dissertation we present and evaluate an approach which addresses these key difficulties. The approach is based on two concepts: using specialized and tightly integrated mass-market applications to provide the bulk of the tool’s functionality, and the use of formal methods for the precise specification of the tool’s domain-dependent modeling language. We have evaluated our component-based work in part by developing a tool using the technique, deploying it to NASA, and having engineers from across the organization use and evaluate it. In the area of formal methods, we have developed and validated, both informally and formally, a mathematically precise specification of the language employed by an innovative modeling and analysis method for the reliability of fault tolerant systems. We have also developed a prototype tool that shows in concrete terms that our combined approach can work. The chief contribution of this work is a new approach to developing software tools having formal foundations for trustworthiness and sophisticated user interfaces. Constituent contributions include a qualified positive evaluation of the component-based approach, a proof of feasibility of using formal methods for domain-specific modeling languages, and the precise definition of an important modeling language, namely one for dynamic fault tree analysis.