ECONOMIC DESIGN OF A COMPLETE INSPECTION PLAN WITH INTERACTIVE QUALITY IMPROVEMENT

Consider the monitoring of an ongoing production process subject to co mplete inspection. Inferior quality products are either reworked or sc rapped to assure good outgoing quality. Whenever the quality character istic of a product exceeds a predetermined action limit, remedial acti on is taken to restore the process to an in-control state. In addition , the decision maker has a learning opportunity to improve the process by investing in resources to identify and eliminate the causes of dev iation from the target quality. Taking a learning action would improve the mean value of the quality characteristic of items produced in an out-of-control state, This paper proposes a cost model to determine th e optimal number of learning actions to be taken and the optimal actio n limit. The model considers the trade-off between quality cost and pr ocess improvement cost.