• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Quality Control and Applied Statistics >On the expected parts per million nonconforming levels obtained from estimated process capability indices
【24h】

On the expected parts per million nonconforming levels obtained from estimated process capability indices

机译：根据估计的过程能力指数得出的百万分之几的预期不合格水平

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Purpose:To present the effects of estimated process capability indices (PCIs) on the parts per million (PPM) nonconforming (NC) estimates are quantified and through evaluating the distributions of PPM NC estimates, to demonstrate that estimation error is critical and might have significant effects on the PPM NC estimates.Summary:Mainly due to six sigma quality management programs where the basic PCIs are used as the standard quality improvement tools applications of at least the basic PCIs, Cp and Cpk, are common in both manufacturing and service industries. However, true process parameters are often unknown in practice and these should be estimated for computing PCIs. The capability indices obtained by using estimated process parameters are random variables and should not be treated as true values. Several studies in the literature investigate the distributions and statistical properties of the capability indices. Despite the errors in estimation, assumptions such as normality and independence of observations may be a concern in practice. This paper focuses on the Cp and Cpk indices with two-sided specification limits. It is assumed that the observations are independent and identically distributed (i.i.d.) normal but with unknown true parameters. To estimate these parameters, widely employed estimators used in quality improvement applications are considered. Followed by this PPM NC item estimates obtained by utilizing PCI estimates are discussed (17 refs.)
机译：目的：介绍估计的过程能力指数（PCI）对百万分之几（PPM）不合格（NC）估计值的影响，并通过评估PPM NC估计值的分布来证明估计误差是关键的，并且可能具有重大意义概述：主要是由于六个sigma质量管理程序，其中将基本PCI用作标准质量改进工具，至少在制造和服务行业中，基本PCI的Cp和Cpk的应用都很普遍。但是，实际中实际的过程参数通常是未知的，应该对这些参数进行估计以用于计算PCI。通过使用估计的过程参数获得的能力指数是随机变量，不应视为真实值。文献中的一些研究调查了能力指标的分布和统计特性。尽管估算存在错误，但实际操作中可能会担心诸如常态和观测独立性之类的假设。本文着重于具有两个规范限制的Cp和Cpk指数。假定观测值是独立的且正态分布相同（i.i.d.），但真实参数未知。为了估计这些参数，考虑了在质量改进应用中广泛使用的估计器。在此之后，讨论了利用PCI评估获得的PPM NC项目评估（17篇参考文献）。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号