An inventory models for product life cycle for deteriorating items with growth of demand - a comparative statement

A product life cycle is the life span of a product which period begins with the initial product specification and ends with the withdrawal from the market of both the product and its support. In all inventory models, a general assumption is that the demand rate is constant. But in real life, the demand rate fluctuates over the period. Growth of demand refers to an increase in demand over an extended period. Two different inventory models are developed for deteriorating items with: 1) the constant demand rate is studied first; 2) the growth of demand is investigated next. A comparative statement between constant demand and growth of demand is carried out. The objective of this paper is to find the optimal cycle time, which minimises the total cost and optimal amount of shortage. The relevant model is built and solved numerical examples are furnished and justified.