臺灣博碩士論文加值系統

近幾年，退化性產品的存貨模式被廣泛地討論，因為在許多存貨管理中，產品退化的考量是不能被忽略的。所謂退化性產品即具有衰退或腐敗後而不能執行其原有功能之性質的產品，舉凡食品、藥品、揮發性液體、放射性物質…等。
本研究的目的在於發展一個退化性產品其需求率呈斜坡型的確定性存貨模式。一般新品牌產品在剛上市時，需求率常隨時間的向前移動而遞增，直到某一時點之後，需求即呈平穩狀態。此外，我們假設產品退化率為時間的遞減函數且允許缺貨而缺貨數量為部份欠撥。
文中我們提出允許週期末發生缺貨及訂購週期開始時便發生缺貨的兩種存貨模式且分別給予數值逼近解。在使單位時間的平均成本為最低的情況下，建立一個選取最適訂購策略的步驟流程，進而求出最適的訂購及補貨策略。最後，舉例說明上述模式的求解過程並對各參數做敏感性分析。

Deteriorating inventory models have been widely studied in recently years, because the effect of deterioration is very important in many inventory systems. Deterioration is defined as decay or damage such that the item can not be used for its original purpose, e.g., food items, drugs and radioactive substances.
In the present paper efforts have been made to analyze an EOQ model for inventory of item that deteriorates at a time-decreasing rate, assuming the shortages quantities will be partial backordered and the demand rate a ramp type function of time. Such type of demand pattern is generally seen in the case of any new brand of consumer goods coming to the market. The demand rate for such items increase, with time up to certain time and then ultimately stabilizes and becomes constant. It is believed that such type of demand rate is quite realistic.
We enumerate two possible shortage models which are permitted to start with shortages and provide an approximate solution, and mathematically identify which has the least expenditures to operate based on the average total cost per unit time. At the end, a numerical example and sensitivity analysis are presented to illustrate the proposed models.

第一章 緒論………………………………………………………1
1.1 研究動機與目的…………………………………………1
1.2 文獻探討…………………………………………………1
1.3 研究架構…………………………………………………2
第二章 期末發生缺貨的存貨模式………………………………4
2.1 符號說明與假設…………………………………………4
2.2 模式Ⅰ的建立……………………………………………6
2.3 範例………………………………………………………12
2.4 敏感性分析………………………………………………13
第三章 允許期初發生缺貨的存貨模式…………………………17
3.1 模式Ⅱ的建立……………………………………………18
3.2 模式Ⅲ的建立……………………………………………24
3.3 三個模式的比較…………………………………………29
3.4 範例………………………………………………………31
3.5 敏感性分析………………………………………………32
第四章 結論………………………………………………………36
4.1 主要研究成果……………………………………………36
4.2 後續研究方向……………………………………………37
參考文獻……………………………………………………………38

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