Generally, an industrial product has more than one quality characteristic. In order to establish performance measures for evaluating the capability of a multivariate manufacturing process, several multivariate process capability indices have been developed based on the assumption of normality. Quality characteristics of many manufacturing processes in the chemical, pharmaceutical and electronic...

T he question of assessing the capability of a process to produce according to some specifications connected with a measurable characteristic (X) of the items produced through it is of great importance in statistical process control. These specifications consist of the lower specification limit (L), which is the minimum acceptable process value; the upper specification limit (U), which is the m...

A profile is a relationship between a response variable and one or more independent variables being controlled during the time. Process Capability Indices (PCI) are measured to evaluate the performance of processes in producing conforming products. Despite frequent applications of profile and a variety of available methods to monitor its different types, little researches have been carried out ...

Montgomery [31] recommended some minimum quality requirements on . For existing processes, the capability must be no less than 1.25, and for new processes, the capability must be no less than 1.45. For existing processes on safety, strength, or critical parameters, the capability must be no less than 1.45, and for new processes on safety, strength, or critical parameters, the capability must be...

The well-known process capability index CPK has been popularly used in the manufacturing industry for measuring process reproduction capability. Existing research papers related to CPK have assumed with no gauge measurement errors. Unfortunately, such assumption does not reflect real situations accurately even with highly sophisticated advanced measuring instruments. Conclusions drawn from proc...

This study examined the effect of agriculture faculty training in and practice of methodologies to explicitly teach critical thinking skills related to course content and subsequent change in student critical thinking disposition. Twelve instructors in 14 agriculture courses underwent a year–long program of instruction in effective critical thinking development. Students completed the Universit...

Process capability index Cpk has been widely used in the manufacturing industry as a process performance measure. In this paper, we investigate the natural estimator of the index Cpk, and show that under the assumption of normality its distribution can be expressed as a mixture of the chi-square and the normal distributions. We also implement the theory of hypothesis testing using the natural e...