适用于GB8052-87中CSP-T方案更优的两类中止规则

连续抽样方案适用于对连续提交的在制品进行抽样检查.人们陆续提出了4类连续抽样方案,即CSP-1、CSP-2、CSP-T和CSP-V,其中CSP-T方案为多水平连续抽样方案.为了监测生产过程质量的稳定性,避免浪费原材料和劳动力,Murphy(1959年)提出了中止规则,可以依据检查数据决定是否中止生产过程,其中中止规则S]已经被国家标准GB 8052-87采用.最近提出的中止规则N,c]R,d]同样适用于CSP-T方案,通过计算其中止参数,与AQL和LQ相应的中止概率P*1和P*2,与中止规则S]的中止特性进行比较后发现:对于CSP-1方案,这两类中止规则明显优于规则S],较之国家标准GB 8052-87采用的中止规则S],无疑是一种有益的改进.

Two Better Stopping Rules for CSP-T in GB 8052-87

Continuous sampling plans are an inspection technique in which inspection is continuous during production and located as an element of a line producing a continuous flow of product. Considering the four classes of continuous sampling plans(CSP),they include CSP-1,CSP-2,CSP-T and CSP-V. Tightened multi level continuous sampling plans CSP-T apply to a steady stream of individual items. In continous production changes in quality can occur suddenly and may require prompt action to avoid wasting material or labor. Such stopping rules have been extensively investigated by Murphy (1959). They are based on inspection data to stop the manufacturing process in order to correct the condition. Today, rule S] is adopted wildly by GB 8052-87. Calculation of parameters of stopping rules, double parameter stopping rules N,c] and R,d], and comparison show that they have more advantages in statistical characteristic on every respect than stopping rule S].