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...

Duncan first proposed the economic design of x control charts in 1956 to control normal process means and ensure that an economic design control chart actually lowers the cost, compared with a Shewhart control chart. Many authors have studied the control charts from economic viewpoint from then on. An economic design does not consider the statistical properties, such as type I or type II error ...

PT. Socfindo Indonesia Seunagan Plantation is a company that produces palm oil and kernel (PKO). This observation aims to determine the parameters of free fatty acids in Plantation. Is it within quality control limits based on Xbar Rbar charts, as well investigations into causes improving with Free Fatty Acid (FFA) parameters. Based results Crude Palm Oil (CPO) chart, number samples for acid le...