本研究以不可逆、連續的閉環輸送系統為研究對象，工件透過工站上料後，常以輸送帶搭配不同載具的形式，按著固定的速度、固定路線及依序經過各個工站進行人工作業後，再由同一個或鄰近的工站下料離開系統。對於一個因受限輸送帶運轉速度而產能有限的輸送系統而言，初步將先應用精實管理工具進行現場改善、消除浪費，再利用離散事件模擬檢視系統現況產出率，最後透過模擬最佳化的方式調整人力水準及人力配置的方式，以嘗試降低由機器干擾問題造成的產能損失，並以一家建材/傢俱製造商的現況固定配置32人的粉體塗裝製程為例來驗證本研究方法的實效。

經實例驗證與敏感度分析，在初步製造現場改善後，現場作業環境增加80平方公尺的彈性作業空間，此外也減少物流人員每日47%移動時間及產線人員作業時間47分鐘。基於初步改善後，在適當的假設及模擬分析後可發現能優化，在不降低由32人達到的既有產出率89%下，以正常作業時間8小時內的產出及人力水準26人的配置方式改善人員利用率來達到節省人力的效果，改善幅度約為18.8%，人員利用率改善幅度則為15%至28%。最後再以敏感度分析來驗證本研究分析在需求波動下的效果。

This research aims to solve a nonreversible, continuous closed-loop conveyor system. The work pieces usually move by carriers which are attached to the conveyor and processed in a constant speed after loaded at the specific station. For such a capacitated production system due to the restricted speed of conveyor, primary we carry out Gemba Kaizen to eliminate the waste through the conception of lean management. Next, we implement a discrete-event simulation that attempt to optimize the staffing level and allocation to reduce the production loss caused by machine interference problem. This research verifies the solution performance through a case study in a powder coating process of a general metal manufacturer with fixed staffing level in 32.
After the verification and improvement in the practical system, the preliminary result shows the Gemba Kaizen can release 80 square meters for flexible space in our case study. In addition, 47% daily transportation time as well as 47 minutes for staffing time can be reduced. Based on those results, we further make appropriate assumptions and propose a simulation optimization experiment. According to the numerical analysis, we can achieve the 89% throughput rate while improving staffing utilization and reducing the staffing level to 26 on the premise of the present situation with staffing level in 32. The staffing level improvement can up to 18.8% and staffing utilization improvement between 15% to 28% . Furthermore, we verify the validity of this research through the sensitivity analysis.

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