Defective units in (Q,r,L) inventory model with sub-lot sampling inspection

This paper assumes that an arrival order lot may contain some defective ite ms, and considers that the number of defective items in the sub-lot sampled to be a random variable. We derive a modified mixture inventory model with backorders and lost sales, in which the or der quantity, reorder point and lead rime are decision variables. In our studies, we first assume that lea d rime demand follows a normal distribution, and then relax the assumption about the form of the distribution Function of the lead time demand and app ly the minimax distribution Free procedure to solve the problem We develop an algorithm procedure to obtain the optimal ordering strategy for each cas e. Furthermore, the effects of parameters are also included.