On an inventory model for deteriorating items with time-varying demand and shortages

Most of the existing inventory models in the literature assume that items can be stored indefinitely to meet the future demands. However, certain types of commodities either deteriorate or become obsolete in the course of time and hence are unstable. For example, the commonly used goods like fruits, vegetables, meat, foodstuffs, perfumes, alcohol, gasoline, radioactive substances, photographic films, electronic components, etc., where deterioration is usually observed during their normal storage period. Therefore, if the rate of deterioration is not sufficiently low, its impact on modeling of such an inventory system cannot be ignored. So deteriorating inventory models have so far been developed and analyzed extensively. This paper presents an approximate method for finding the inventory replenishment schedule for a deteriorating item with non monotonous demand rate.