在一個高度競爭的世代中，產品生命週期因為顧客喜好的快速變遷而迅速縮短；而具有如此特性的產品通常僅有為數不多的歷史資料可供未來之需求預測使用，因此既有的預測方法不敷使用，造成許多製造業在庫存管理上面臨極大的挑戰。傳統的存貨管理模型主要是處理已進入成熟期的產品，所以產品的需求量通常假設為穩定的，但這樣的假設與求解方法不適用於短生命週期的產品。而在1969由Frank M. Bass發展出的擴散模型正好對短生命週期的產品具有較佳的預測能力，因此本研究以Bass模型為基礎建構一個完整的成本架構來描述補貨的流程所須之花費，此外我們放寬了既有的模型中常用的假設，將部分缺貨後補的情況亦考慮至此研究中，最後我們針對模型中的參數進行分析與探討。

In the so-called hyper-competitive age, the product life cycle is shortening rapidly. The shortened life cycles are caused by fast changing consumer preferences that lead to a fashion or fad effect. Due to the innovative nature of the product, usually a few historical data is available for forecasting demand of such products. Many companies of manufacturing industries are facing challenge of inventory management greater than before. Traditional models and methods for making the inventory plan mainly deal with products in the maturity stage. As the product enters its mature stage in the product life cycle, its demand is assumed to be constant or probabilistically stable. The assumption and solution approach for product in such a stage may not be suitable for products with short life cycle. Bass diffusion model proposed by Frank M. Bass (1969) has a good fit to the demand of products with short life cycle.
In this research, we recommended a complete cost function to model the common expenditure possibly appear in the replenishment process based on the Bass model. Furthermore, we considered the situation of unmet demand which can be partial backordered. It relaxed the assumption that the shortages of product are completely backordered of many proposed inventory models. Finally, we used WW approach to find the optimal order policy and analyzed the effects of the parameters in our model.

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