Traditionally, the statistical quality control techniques utilize either an attributes or variables product quality measure. Recently, some methods such as three-level control chart have been developed for monitoring multi attribute processes. Control chart usually has three design parameters: the sample size (n), the sampling interval (h) and the control limit coefficient (k).The design parame...

Control charts are used to identify the presence of assignable cause of variation in the process. Non-parametric control chart is an emerging area of recent development in the theory of SPC. Its main advantage is that it does not require any knowledge about the underlying distribution of the variable. In this paper a non-parametric control chart for controlling variability has been developed. I...

The common consideration on economic model is that there is knowledge about the risk of occurrence of an assignable cause and the various cost parameters that does not always adequately describe what happens in practice. Hence, there is a need for more realistic assumptions to be incorporated. In order to reduce cost penalties for not knowing the true values of some parameters, this paper aims ...

Usually, in monitoring a proportion p < /em>, the binary observations are considered independent; however, in many real cases, there is a continuous stream of autocorrelated binary observations in which a two-state Markov chain model is applied with first-order dependence. On the other hand, the Bernoulli CUSUM control chart which is not robust to autocorrelation can be applied two-sided co...

This paper is concerned witl). "a problem in which a firm is engaged in manufacturing a number of types and sizes of goods at equal intervals, e. g. monthly, and the production is forced to fulfill the customer's demand immediately. In general the products are subject to considerable variations in demands. Let us assume that the amount demanded is uncertain but has a certain probability distrib...

Background and objectives: Risk-adjusted Bernoulli control chart is one of the main tools for monitoring multistage healthcare processes to achieve higher performance and effectiveness in healthcare settings. Using parameter estimates can lead to significantly deteriorate chart performance. However, so far, the effect of estimation error on this chart in which healthcare ...

Control chart patterns (CCPs) can be associated with certain assignable causes, and recognition of such patterns can assist the diagnostic search for those causes. Variations could be one or more instances of trend, cyclic, hugging, sudden shift or some other variations over time. Each pattern has special statistical characteristics which differentiate one pattern from another. In a time series...

when a change occurs in a process, one expects to receive a signal from a control chart as quickly as possible. upon the receipt of signal from the control chart a search for identifying the source of disturbance begins. however, searching for assignable cause around the signal time, due to the fact that the disturbance may have manifested itself into the rocess sometimes back, may not always l...

Abstract:&#x0D; In many real-world applications, the data to be used in a control charting method are not crisp since they approximated due environmental uncertainties, these situations, fuzzy numbers and linguistic variables grab such uncertainties. That is why use of chart, which used, justified. As an exponentially weighted moving average (EWMA) scheme usually detect small shifts, this paper ...

The reliability data is getting used to monitor and improve the quality of products or services. Nowadays, most of products or services are the results of processes with dependent stages referred to as multi-stage process. In these processes, the quality characteristics are affected by the quality characteristics in the previous stages, called as cascade property. In some cases, it is not possi...