Journal ArticleDOI
Cumulative quantity control charts for monitoring production processes
TLDR
In this article, the cumulative quantity control chart (CQC-chart) is introduced for monitoring high-yield processes with low defect rates, which can be used no matter whether the process defect rate is low or not.Abstract:
Two commonly used statistical quality control charts, the c-chart and u-chart, are unsatisfactory for monitoring high-yield processes with low defect rates. To overcome this difficulty, a new type of control chart called the cumulative quantity control chart (CQC-chart) is introduced in this paper. The CQC-chart can be used no matter whether the process defect rate is low or not, and when the process defect rate is low or moderate the CQC-chart does not have the shortcoming of the c- and u-charts of showing up false alarm signals too frequently. The CQC-chart does not require rational subgrouping of samples (which is necessary for the c- and u-charts), and is appropriate for monitoring automated manufacturing processes.read more
Citations
More filters
Journal ArticleDOI
Some effective control chart procedures for reliability monitoring
TL;DR: A recent control scheme based on the cumulative quantity between observations of defects has been proposed which can be easily adopted to monitor the failure process for exponentially distributed inter-failure time and can detect process improvement even in a high-reliability environment.
Journal ArticleDOI
Designing production systems for quality: Research opportunities from an automotive industry perspective
TL;DR: In this article, the authors explore the intersection of two research areas: quality and production system design, and argue that the production system used to manufacture a product does indeed affect its quality.
Journal ArticleDOI
Control Charts Based on the Exponential Distribution: Adapting Runs Rules for the t Chart
Eduardo Santiago,Joel Smith +1 more
TL;DR: In this article, a probabilistic-based method to construct a t chart to monitor the stability of a process is presented, assuming that the time between events can be modeled with an exponential distribution, and applying the supplementary runs rules to identify whether the process is out of control.
Journal ArticleDOI
A control chart for the Gamma distribution as a model of time between events
TL;DR: In this article, a random-shift model for calculating the out-of-control average time to signal (ATS) of the Gamma chart is developed, which is shown to be much more accurate than the conventional method based on a fixed shift model through comparing with Monte Carlo simulation.
Journal ArticleDOI
An Overview of Control Charts for High‐quality Processes
TL;DR: Time-between-events control charts detect an out-of-control situation without great loss of sensitivity as compared with existing charts, and draw a precise conclusion from the statistical point of view.
References
More filters
Journal ArticleDOI
Quality Control Techniques for "Zero Defects"
TL;DR: In this paper, the authors propose to use a control chart that plots the number of good items between defects on a logarithmic scale to accommodate large numbers, establishing upper and lower limits on the number between defects.
Journal ArticleDOI
A Control Chart for Parts-Per-Million Nonconforming Items
TL;DR: A control chart for parts-per-million nonconforming items is presented in this article, with a focus on parts per-million nonconformity in parts per million items.
Book
Advanced Topics in Statistical Process Control: The Power of Shewhart's Charts
TL;DR: The Power of Shewhart's Charts as discussed by the authors is a seminal work in statistical process control that describes the power of Shehart's charts and its application in statistical processes.
Journal ArticleDOI
Some procedures for decision making in controlling high yield processes
Min Xie,Thong Ngee Goh +1 more
TL;DR: In this paper, a decision graph is introduced with which we can easily judge whether the process is out of control when a non-conforming item is observed after a number of conforming ones, accompanied by the certainty level of this judgement.
Journal ArticleDOI
Control Schemes for Low Count Levels
TL;DR: The count of counts which occur at very low levels is discussed in this article, where very low count levels can be below the range of counts covered in a previous article on Counted Data CUSUMS.