Parts with high NC rates, large lot sizes, and high ci/ti ratios are recommended for a thorough inspection (e.g., parts #19, #4, #1, and #18).
This example has confirmed the principle of sample size decisions for resource-constrained incoming inspections is to treat parts differently by taking into account their NC risks and severity, lot size, as well as cost-effectiveness of the incoming inspection. The parts high in NC risk and severity are recommended for thorough inspections. When the inspectors’ time is limited, the inspection priority is given to parts that have large lot sizes and are highly cost-effective in incoming inspections. The optimization model developed in this paper helps calibrate sample size decisions based on this principle.