相關不良品檢驗對生產過程管制的影響

Abstract

In a continuous production process,samples of the products are taken and inspacted at regular time intervals.A statistic of each sample is plotted on a chart to control the production process.In many cases, the inspection of one attribute X of the product is too costly(e.g. destructive inspection), and one would try to take a less costly but less reliable inspection of another attribute Y of the product . This paper tries to answer the question that under what conditions this new attribute Y should be inspected. A simple Markov model for the production process is presented and the cost factors including cost of a defective, cost of inspection and cost of taking corrective action are considered.An approximate relationship between two different inspection costs corresponding to X and Y is found when both inspections are under optimal inspection schemes.