企業競爭激烈,面對產品需求大量變動,存貨管理在企業經營中扮演著相當重要的角色,存貨不足產生缺貨成本,而大量或過渡的存貨亦可能造成資金積壓,所以制訂存貨策略時,如何取得平衡對於公司營運上佔相當重要的一環。實務上,可發現一般系統的存貨紀錄皆存在誤差,而早期研究常忽略之,制訂出不正確之存貨策略,進而導致缺貨情形發生,抑制公司獲利空間,因此本研究考量二階層存貨系統中存貨紀錄的正確性,探討電子資訊系統導入單一階層或二階層時,系統紀錄存在誤差與否對制訂存貨策略、整體或局部供應鏈績效之影響。 本論文針對單一產品的二階層存貨系統,其中包含單一配銷中心與單一零售商,為考量存貨紀錄是否存在誤差,因而提出四種模式,分別為上下階層存貨紀錄不正確、下階層存貨紀錄不正確、上階層存貨紀錄不正確與上下階層存貨紀錄正確(當導入電子資訊系統時,該階層存貨紀錄正確),並採用兩種決策法則(兩階段法則與協同決策法則),以最小化二階層存貨系統總相關成本為目標,藉由程式搜尋找出最佳存貨策略。爾後,透過變動的需求量及需求變異與相關成本參數來進行研究,觀察趨勢變動對整體的影響。結果發現當二階層存貨系統皆導入電子資訊系統時,採用協同決策法則,使管理者能隨時掌控正確紀錄,得到最小化二階層總相關成本。
This study considers a two-echelon inventory system where inaccuracy of records on inventory exists. The inventory system is composed of one distributor and one retailer. The objective is to evaluate the effect of system related costs when improve inventory record accuracy of the system. Four models are constructed: the system where both echelons exhibit inventory inaccuracy, the systems where either the first echelon or the second echelon has inaccuracy inventory information and the system with perfect inventory record at both echelons. Two decision strategies (sequential strategy and coordinated strategy) are discussed when searching for the best inventory policy based on the minimum total cost of the two-echelon inventory system. System-related cost functions for the four models are derived and a search algorithm for optimal replenishment policies is proposed. An intensive numerical study is conducted and the performance of the four models is compared and analyzed. It can be shown that system costs can be reduced significantly by improving inventory accuracy.