臺灣博碩士論文加值系統

調貨政策為存貨分享的一種手段，當發生缺貨的零售商，能夠從附近有足夠存貨的零售商進行調貨，將體系中的存貨進行重新分配。本研究針對顧客需求為隨機型態的多站存貨模式，建構最小化系統總成本的最佳存貨模式，決定零售商的最高存貨水準 (order-up-to level)。各零售商面對隨機型態的需求且允許貨物於不同零售點間調貨，但不同區域的零售商礙於地理位置的關係，僅允許在同一銷售區域的零售商進行調貨。
數值求解程序以蒙地卡羅抽樣逼近法的方式建立。改善機制以總成本的梯度值更新每一次迭代中最高存貨水準。敏感度分析中，在需求變動幅度小的時候，所有系統中在平均最高存貨水準變動幅度為 -25%時較變動幅度為 +25%時的總成本較高。當需求變動幅度愈來愈大時，則考慮調貨政策下，平均最高存貨水準變動幅度 -25%與 +25%時，其總成本接近一致。這現象表示存貨水準高或者是低時，當某些零售商面零缺貨時或者存貨過多時，都可以藉由調貨政策來調掉存貨，使得系統中的成本降低。

Transsipment policy is a means of sharing stock. When the retailer is running out of stock, they can transship (get the goods) from the retailers nearby who have enough stock and re-distribute the stock of the system. This research is aiming to the customer whose demand is multi stock station of random status and is building the best stock pattern of minimized total cost system to decide order-up-to level of retailers. The retailers follow the pattern of random status to transship among different retailing locations. But concerning the geographic location, the retailers will only allow to transship in the same area.
The solver algorithm is using Monte Carlo sampling approximations. The mechanism of improvement is using the gradient of total cost to update the order-up-to level on each generation. In the sensitivity analysis, when the scale of changes of demand is small, as the scales of -25% changes of the average order-up-to level are better than the scales of +25% changes in all systems, the total cost is higher. When the scales of changes of demand is increased in transshipment policy, the total cost is to be close in the scales of -25% and +25% changes of the average order-up-to level. It represents the inventory level is either higher or lower adjust inventory level by using transshipment policy to reduce total cost of the systems when some retailers faced shortage of stock or excess of stock.

中文摘要 -------------------------------------------------------------------------- i
英文摘要 -------------------------------------------------------------------------- ii
誌謝 -------------------------------------------------------------------------- iii
目錄 -------------------------------------------------------------------------- iv
表目錄 -------------------------------------------------------------------------- v
圖目錄 -------------------------------------------------------------------------- vi
一、 緒論--------------------------------------------------------------------- 1
1.1 研究背景與動機------------------------------------------------------ 1
1.2 研究目的--------------------------------------------------------------- 2
1.3 研究範圍與假設------------------------------------------------------ 2
1.4 研究流程--------------------------------------------------------------- 2
二、 文獻探討--------------------------------------------------------------- 5
2.1 存貨模式與政策------------------------------------------------------ 5
2.2 風險共擔--------------------------------------------------------------- 6
2.3 多站存貨配銷系統--------------------------------------------------- 9
2.4 調貨政策--------------------------------------------------------------- 10
2.4.1 緊急調貨與預防調貨------------------------------------------------ 11
2.4.2 完全調貨與部份調貨------------------------------------------------ 11
2.5 調貨政策下多站存貨模式------------------------------------------ 12
三、 數學模式建立--------------------------------------------------------- 13
3.1 符號說明--------------------------------------------------------------- 14
3.2 模型假設--------------------------------------------------------------- 15
3.3 模型建立--------------------------------------------------------------- 16
3.4 調貨量的限制--------------------------------------------------------- 17
3.4.1 各區域中貨車配送容量限制--------------------------------------- 17
3.4.2 部分存貨分享--------------------------------------------------------- 18
3.5 隨機規劃問題--------------------------------------------------------- 20
3.6 數值求解程序--------------------------------------------------------- 22
四、 模型求解與敏感度分析 -------------------------------------------- 24
4.1 數值範例 -------------------------------------------------------------- 24
4.2 實驗設計--------------------------------------------------------------- 28
4.2.1 參數設定--------------------------------------------------------------- 28
4.2.2 研究結果--------------------------------------------------------------- 29
4.3 敏感度分析------------------------------------------------------------ 35
五、 結論--------------------------------------------------------------------- 41
5.1 研究結論--------------------------------------------------------------- 41
5.2 未來研究方向--------------------------------------------------------- 42
參考文獻 -------------------------------------------------------------------------- 43

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