An economic-statistical production quantity model under quality-maintenance policy for imperfect manufacturing systems with interaction effect among assignable causes

This study integrates production and maintenance planning with statistical process monitoring in the presence of dependent multiple assignable causes. To adapt model to reality, two assumptions are considered: (1) causes (ACs) dependent, (2) occurrence ACs can affect both mean variability. Given second assumption, a non-central chi-square (NCS) chart is used monitor process. Since rate increases over time, non-uniform sampling scheme presented reduce out-of-control time period. A sensitivity analysis explore how number AC types influences cost terms. The results indicate that more types, higher quality loss costs imposed on manufacturer. Moreover, three comparative studies conducted for confirming effectiveness model. first shows total will be less than its real value when interdependency among ignored. comparison NCS outperforms detecting disturbances leads cost. Eventually, last one represents employing strategy significant savings.