Variable processes are those in which direct measurements can be made of the quality characteristic in a periodic or daily sample. The daily samples are then compared with a historical record to see i...

Control charts have been traditionally used as the method of determining the performance of manufacturing processes over time by the statistical characterization of a measured parameter that is depend...

Chi-square(X 2)  tests can be used determine whether a set of data can be adequately modeled by a specified distribution. The chi-square test divides the data into nonoverlapping intervals calls ...

Using graph paper, spreadsheets, or statistically based software, measurement data from randomly selected samples of parts can be quickly checked for normality as follows: 1. Randomly select a nu...

In the electronics industry, if you want to maintain your competitiveness, you need to constantly improve your process to ensure the quality of production. This will attract more customers and retain...

For attribute processes (those with quality measured in terms of defects in a sample or number defective), an implied Cpk will have to be calculated in the quality assessment of design and manufacturi...

Many companies are beginning to think about the process capability index, be it six sigma or Cpk, as a good method for both design manufacturing engineers to achieve quality goals jointly, by having b...

Although both six sigma and CPK are excellent measurement systems for quality improvement in design and manufacturing , a consensus has not been reached as to which system should be selected based on ...