Dependable Systems Integration using Measurement Theory and Decision Analysis

Modern computer systems are becoming increasingly complex ensembles of hardware and software. This complexity has many facets, such as the number and diversity of the constituent components, the range of technologies employed, and the complex interactions between the components. If these interactions are unexpected, they may lead to system failures that could result in undesirable or even catastrophic consequences. This is especially of concern in the large, increasingly sophisticated, systems that are being used to control critical services in application areas such as medicine, transport, defence, and finance. Many properties of a system become visible only upon integration (when the components are assembled) --- these are called `emergent' properties. They are particularly difficult to control and predict during the development process. The dependability of a system is one such property which we study in detail in this thesis. For systems to be dependable, their behaviour must be pr..