Inventory Model for Items with Weibull Deterioration, Ramp Type Demand and Shortages

The present paper presents an economic order quantity model for the inventory of a deteriorating item with demand rate as a ramp type function of time, in which the inventory is permitted to start with shortages and end without shortages. A two-parameter Weibull distribution is used to represent the distribution of the time to deterioration. A theory is developed to find the optimal solution of the problem. Several numerical examples are then taken to illustrate the solution procedure. Finally, sensitivity of the optimal solution to changes in the values of different system parameters is also studied.