Statistical Process Control (SPC) charts are widely used in manufacturing industry for monitoring the performance of sequential production processes over time. A common practice using a control chart is to first collect samples and take measurements certain quality variables from them at equally-spaced sampling times, then make decisions about process status by based on observed data. In some a...

abstract. in recent years several studies have shown that  control charts with adaptive schemes or double sampling plans detect both small and moderate shifts in the process mean more quickly than the traditional shewhart  chart. in the classical double sampling  chart, the difference between two points were placed in the central region of first stage was not considered. in this study, a new co...

a chromium electroplating bath with the ability to produce homogenous mist was used to evaluate parameters influencing hexavalent chromium (cr+6) mist sampling methods. the results of 48 cr+6mist samples collected using the u.s. national institute for occupational safety and health method 7600showed that cr+6concentration was higher: (1) for sampling by closed-face filter cassettes than for sam...