F 公司每月安排生產計畫時，除了新品訂單，也需要處理客戶退回後經檢查、維修或重工完成的良品訂單。由於兩類訂單共用相同產線，實際上會納入同一份月度生產計畫。公司目前主要依訂單成立或需求確認順序安排，並以新品優先為主。此方式容易執行，但當訂單的交期、數量、加工時間與重要程度不同時，固定排序不一定能兼顧整體交期表現。
本研究先使用層級分析法（Analytic Hierarchy Process, AHP），蒐集研發、品質、業務、生產管理、製造及售後服務等六個部門共 12 位主管的意見，從交期緊迫性、顧客滿意度影響、品質與庫存風險及生產效率影響四個面向，評估新品與重工良品在排程上的相對重要性。計算結果顯示，新品訂單權重為 0.5994，重工良品訂單權重為 0.4006。接著將兩項權重導入混合整數線性規劃（Mixed Integer Linear Programming, MILP）模型，並使用 Python 與 Gurobi 進行求解。

本研究選取 F 公司 2025 年 6 月 10 筆訂單及 2025 年 10 月 14 筆訂單作為實際案例，比較 FIFO／新品優先、重工良品優先、最短加工時間優先（Shortest Processing Time, SPT）、最早交期優先（Earliest Due Date, EDD）及 Gurobi 求解排序共五種策略。於 10 筆訂單案例中，Gurobi 與 SPT 的總加權延遲時間皆為 15.405，低於 FIFO／新品優先的 46.559，改善約 66.9%，交期達成率亦由 10% 提高至 60%。Gurobi 在 Final Gap 為 0%、求解狀態為 OPTIMAL 時，其目標函數值與 3,628,800 種全排列所得最低值一致，確認所得排程為本案例的全域最佳排序之一。
在 14 筆訂單案例中，Gurobi 的總加權延遲時間為 24.875，低於其餘四種策略，交期達成率為 64.3%；Final Gap 約為 4.98%，符合本研究設定的 5% 容許標準。權重敏感度分析顯示，在測試範圍內，Gurobi 仍維持最低或與最低值相同的總加權延遲。整體而言，在固定產能下適當調整訂單順序可改善延遲與交期表現；AHP 提供跨部門產品重要性基準，MILP 則依交期、加工時間與權重產生量化排程參考。本研究尚未納入臨時插單、缺料、設備故障、人力變動及換線時間，後續可再擴充。

Company F schedules both new product orders and reworked products on the same production line. The current practice mainly follows order creation or demand confirmation, with new products generally given priority. Although easy to implement, a fixed sequence may not provide better delivery performance when due dates, quantities, processing times, and product importance differ.
This study applies the Analytic Hierarchy Process (AHP) using responses from 12 managers in six departments and four criteria: due-date urgency, customer satisfaction impact, quality and inventory risk, and production efficiency impact. The resulting weights are 0.5994 for new product orders and 0.4006 for reworked product orders. These weights are incorporated into a Mixed Integer Linear Programming (MILP) model solved with Python and Gurobi. Two actual cases are analyzed: 10 orders from June 2025 and 14 orders from October 2025. Five strategies are compared: FIFO with new-product priority, reworked-product priority, Shortest Processing Time (SPT), Earliest Due Date (EDD), and Gurobi.
For 10 orders, Gurobi and SPT both achieve total weighted tardiness of 15.405, about 66.9% lower than FIFO, while on-time delivery increases from 10% to 60%. For 14 orders, Gurobi achieves the lowest value of 24.875 and 64.3% on-time delivery; the 4.98% Final Gap satisfies the 5% tolerance. Overall, appropriate resequencing can improve delivery performance under fixed capacity.

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