SPC技术应用及应注意的几个问题

本文分析了企业实施SPC管理的重要作用，阐述了SPC的实施程序，根据实施经验重点总结了SPC应用过程中应注意的几个问题。     

基于SPC的汽车传动轴生产质量控制研究

SPC是产品生产过程质量控制的有效方法。汽车传动轴是影响汽车安全的重要部件。笔者结合在汽车传动轴企业工作的实际,研究了基于SPC的汽车传动轴生产质量控制,并提出了相关建议。     

SPC控制图数据采集过程研究

SPC控制图即应用统计分析方法对生产过程进行监控,科学地区分出生产过程中产品质量的正常波动与异常波动,从而对生产过程的异常趋势提出预警。质量控制图数据的采集工作是质量过程监控的关键,为了保证数据采集的真实性、及时性和可靠性,文章通过分析SPC控制图原理,确定了过程关键质量特性参数,将参数的测量方法和抽样方法标准化,提出了数据采集过程中的注意事项及原则。     

浅论SPC的应用

介绍了SPC的目的、概念和原理。并对X－R图为例,介绍了控制图的建立流程及其日常应用中应注意的问题。强调SPC的作用是预防浪费、预防缺陷发生以降低成本。     

螺栓拧紧的统计过程控制

文章指出了批量生产条件下测得的螺栓拧紧扭矩符合正态分布规律，因此可以通过采用统计过程控制(SPC)对装配拧紧工序进行监控。文中介绍了实施SPC时常用的控制图和能力指数等方法，并以实例予以说明。     

企业应用SPC的几个误区

作为一种提高产品质量和保证能力的重要技术措施，统计过程控制技术（SPC）在国内外各类生产厂家得到了普遍重视，本文针对SPC统计过程控制技术在企业应用时经常遇到的一些问题进行探讨，旨在推进SPC的贯彻和实施。     

基于SPC的软件项目过程管理

SPC是软件项目过程管理中一种基于数理统计的新方法。文章从SPC的由来、发展及分析框架入手,通过实例叙述了SPC的具体应用,并指出了软件项目过程管理中实施SPC的难点。     

P控制图在植球工艺中的应用

本文简述了BGA植球工艺SPC的运用。阐述了锡球共面性的SPC控制方法，共面性最大值的单值控制图和共面性缺陷率的p控制图。同时，给出了两种p控制图控制限的算法及应用范围。通过实例，解释了p控制图应用在锡球共面性的应用优势和两种控制限计算方法的失控情况。     

多变量指数加权移动平均控制图的信息识别

1问题的提出由于传感测量技术以及计算机的广泛应用,增强了监控一个过程关键变量的能力,因此,一体化多变量统计过程控制(SPC)的能力与多变量过程控制程序在工业生产物流过程中的应用不断增加,同时,随着新技术的出现,多变量SPC应用更加广泛。如1988年Crosier把原来的T2图扩展为累加和程序;1992年Lowry等人提出指数加权移动控制图的多变量模型,以及1995年提出的对于多变量质量控制的更深入更细致的检查等。在多变量过程的监控程序中,多变量指数加权移动平均(MEWMA)控制图是极为有用的多变量控制图之一。谢沃特型控制图如T2与X2图,在处…     

SPC在济钢二炼钢厂生产过程控制中的有效应用

济钢第二炼钢厂通过在生产过程中使用SPC，辨识对产品质量有重大影响的方坯连铸特殊工序，并通过控制连铸工序的中包温度、钢坯[S]含量等重要因素，优化 了生产工艺参数，提高了产品内在质量，使生产过程达到稳定并持续改进。     

Beyond improved quality: the motivational effects of statistical process control

The deployment of statistical process control (SPC) in manufacturing environments is a prominent global phenomenon. Managers have frequently justified investments in SPC by citing and/or demonstrating the improvements in quality and costs from the effective implementation and practice of SPC. This paper complements this rationalization by presenting conceptual arguments and empirical evidence to further our understanding of the motivational effects that result from the deployment of SPC within production environments. Several hypotheses derived from relating the deployment of SPC to process operators’ jobs and their affective reactions to work are tested using data provided by 100 process operators. The empirical results, generated from applying path analysis, suggest that the effective implementation and practice of SPC, in fact, would create more enriched jobs for process operators that lead to higher levels of work motivation and job satisfaction.     

浅析物流业的SPC技术应用

目前，中国的物流产业方兴未艾，SPC技术作为一种过程控制方法，运用数理统计和概率论原理，及时发现物流过程中的异常情况，从而及时采取措施，使物流过程不断趋于受控状态。SPC技术是科学的物流事前管理，是物流成功的第一步．本文用实例说明SPC技术在物流业的具体应用以及在应用过程中应注意的一些问题。     

基于Wilcoxon秩和检验的多元非参数控制图

在统计过程控制(SPC)中,对多元数据的监测仍然是一个重要且具有挑战性的问题。当缺乏或有限的关于潜在过程分布的认知时,特别是当过程测量是多变量的时候,非参数控制图在统计过程控制(SPC)中是有用的。文章基于Wilcoxon秩和检验结合广义加权移动平均(GWMA)控制方案来制定图表统计量,得到一个新的多元非参数控制图,用于监测多元数据的位置参数变化。文章的理论和数值研究表明,所提出的控制图能够为任意数据分布位置偏移检测提供令人满意的性能。     

Monitoring processes with changing variances

Statistical process control (SPC) has evolved beyond its classical applications in manufacturing to monitoring economic and social phenomena. This extension has required the consideration of autocorrelated and possibly non-stationary time series. Less attention has been paid to the possibility that the variance of the process may also change over time. In this paper we use the innovations state space modeling framework to develop conditionally heteroscedastic models. We provide examples to show that the incorrect use of homoscedastic models may lead to erroneous decisions about the nature of the process.     

Using On-Line Process Data to Improve Quality: Challenges for Statisticians*

In the process industries measurements on a large number of process variables are routinely collected at regular intervals by on-line computers. This paper makes a case for incorporating these process variables into Statistical Process Control (SPC) schemes. Multivariate statistical methods such as Principal Component Analysis (PCA) and Partial Least Squares (PLS) can be used to project these data down into low dimensional spaces where analysis, monitoring and diagnosis are easily performed. Strong justifications for taking this approach are presented and examples are given. The statistical process control community has been slow in adapting to the data explosion brought about by the computer era. It has continued to stick with traditional control charts on the quality variables and ignored this rich source of additional information on the process. This paper explores some of the reasons for this and argues that the SPC community must adapt rapidly or lose control of the field to scientists and engineers. The paper also tries to induce statisticians into looking more seriously at the many unsolved problems in this area of reduced rank multivariate statistics.     

Run length analysis of Shewhart charts applied to drifting processes under an integrative SPC/EPC model

Engineering Process Controllers (EPC) are frequently based on parametrized models. If process conditions change, the parameter estimates used by the controllers may become biased, and the quality characteristics will be affected. To detect such changes it is adequate to use Statistical Process Control (SPC) methods. The run length statistic is commonly used to describe the performance of an SPC chart. This paper develops approximations for the first two moments of the run length distribution of a one-sided Shewhart chart used to detect two types of process changes in a system that is regulated by a given EPC scheme: i) changes in the level parameter; ii) changes in the drift parameter. If the drift parameter shifts, it is further assumed that the form of the drift process changes from a linear trend under white noise (the in-control drift model) into a random walk with drift model. Two different approximations for the run length moments are presented and their accuracy is numerically analyzed. Received: August 1998     

浅谈电力系统中的行政程控交换机

程控交换机在电力行业得到广泛应用,文章简要论述了程控交换机的维护特点和程控交换机在维护和管理过程中的相关事项,并结合工作实际介绍在连江供电公司的使用情况。     

SPC技术在铝合金挤压过程中的应用

运用统计过程控制对铝型材的尺寸进行统计分析,发现并采取措施消除异常波动,实现过程稳定,提高生产效率的目的。