Presents a modification of Saniga′s model for joint economic design of process control parameters, i.e. sample size, sampling frequency and critical regions for X and R charts. The objective is to minimize the total system cost, which consists of the cost of sampling and charting, the cost of...

Presents two production models for maintaining current control of an industrial process under the surveillance of an np ‐control chart. The first model assumes that the process is not allowed to continue in operation during the search for the assignable cause. The second assumes that the...

The double exponentially weighted moving average (DEWMA), which is known in the literature as Brown′s one‐parameter linear method for forecasting is proposed as a control tool for process monitoring and detecting shifts in the process mean. Obtains a closed‐form expression for the...