The nonparametric (NP) control charts are famous for detecting a shift in the process parameters (location and/or dispersion) when underlying characteristic does not follow distributional assumptions. Similarly, cost of estimations is very high and ranking observational relatively simple, ranked set sampling (RSS) technique preferred over simple random (SRS) technique. On other hand, NP triple ...

PT. XX. is a company engaged in the automotive sector, precisely production of metal components, always prioritizing and trying to create products with high quality, but process until now, reject are still found both during after passing inspection, while zero defects become standard process. Based on data obtained from August November 2021, part number 57835-0K020 product highest rejects. In t...

control chart is the most well-known chart to monitor the number of nonconformities per inspection unit where each sample consists of constant size. generally, the design of a control chart requires determination of sample size, sampling interval, and control limits width. optimally selecting these parameters depends on several process parameters, which have been considered from statistical and...

a new method is developed for a fast identification of the stability situation of industrial processes. the proposed method includes two factor ratios of the control constants for the upper and lower control limits to process these constants. an indication ratio is then defined as the ratio of the maximum data range value to the difference between the maximum and average values for individual d...

Control charts, known for more than 80 years, have been important tools for business and industrial manufactures. Among many different types of control charts, the attribute control chart (np-chart or p-chart) is one of the most popular methods to monitor the number of observed defects in products, such as semiconductor chips, automobile engines, and loan applications. The attribute control cha...

The performance of attributes control charts (such as c and np charts) is usually evaluated under the assumption of known process parameters (i.e., the nominal proportion of nonconforming units or the nominal number of nonconformities). However, in practice, these process parameters are rarely known and have to be estimated from an in-control phase I data set. In this paper, we derive the run l...