usually, in monitoring schemes the nominal value of the process parameter is assumed known. however, this assumption is violated owing to costly sampling and lack of data particularly in healthcare systems. on the other hand, applying a fixed control limit for the risk-adjusted bernoulli chart causes to a variable in-control average run length performance for patient populations with dissimilar...

The quality characteristic(s) are assumed to follow the normal distribution in many control chart constructions, although this assumption may not hold some instances. This study proposes Bayesian-I and Bayesian-II Shewhart-type charts for monitoring Maxwell scale parameter phase II study. posterior predictive distributions used construct limits proposed charts, respectively. Various performance...

Control charts have been used effectively for years to monitor processes and detect abnormal behaviors. However, most control charts require a specific distribution to establish their control limits. The bootstrap method is a nonparametric technique that does not rely on the assumption of a parametric distribution of the observed data. Although the bootstrap technique has been used to develop u...

In the past few years, there has been an increasing interest in developing project control systems. The primary purpose of such systems is to indicate whether the actual performance is consistent with the baseline and to produce a signal in the case of non-compliance. Recently, researchers have shown an increased interest in monitoring project’s performance indicators, by plotting them on the S...

Change point estimation in the area of statistical process control has received considerable attentions in the recent decades because it helps process engineer to identify and remove assignable causes as quickly as possible. On the other hand, improving in measurement systems and data storage, lead to taking observations very close to each other in time and as a result increasing autocorrelatio...

Under estimated in-control parameters, the Phase II control chart performance is expected to vary among practitioners due to the use of different Phase I data sets. Accordingly, the typical measure of Phase II control chart performance, the average run length (ARL), becomes a random variable. In the literature, control charts with estimated parameters were assessed and the appropriate amounts o...

Many problems do not have one or more variables that determine quality characteristics. In these situations, as a solution method, profile is descibed by linking independent to the response variable. One of common assumptions in most monitoring schemes assumption residuals. Contravention this can lead misleading results control chart. On other hand, when data are contaminated, classical methods...

In the continuous gas lift operation, compressed gas is injected into the lower section of tubing through annulus. The produced liquid flow rate is a function of gas injection rate and injection depth. All the equations to determine depth of injection assumes constant density for gas based on an average temperature of surface and bottomhole that decreases the accuracy of gas lift design. Also g...