Verification, Validation, and Testing of Engineered Systems

7.1 SYSTEMS’ QUALITY COSTS IN THE LITERATURE

System VVT encompass the ensemble of activities used in order to ensure the quality of engineered systems. The main objective of the VVT process is to identify system problems (e.g., in requirement definition, system design, system implementation, production processes, maintenance practices, system disposal).

Most of the system research (as opposed to software research) related to quality cost does not provide actual and specific data. Kumar et al. (1998) discuss the subject of collecting, measuring and reporting quality cost data in various countries. They also compare between different quality cost components based on empirical findings. Hwang and Aspinwall (1996) review different quality cost models, comparing both the strengths and the weaknesses of each model, and highlight their application in different areas. Several researchers describe models and applications in specific industries such as telecommunications (Hwang and Aspinwall, 1999), construction (Aoieong et al., 2002) and automotive (De Ruyter et al., 2002). Other researchers expand the traditional definition of quality cost to so-called invisible and, in particular, intangible costs (Chiadamrong, 2003).

Some system researchers provide real hard quality cost data. For example, Burns (1976) measured the quality costs in a machine tool company, and these costs were the equivalent of 5% of the sales turnover. The distribution of the total 100% quality costs was prevention ...