近年來，隨著世界各地許多工廠的發展，製鞋業正在迅速發展，尤其是在越南，印度尼西亞，緬甸等勞動力成本可承受的東南亞國家。這給工廠帶來了越來越多的訂單。然而，工廠必鬚麵對一些關鍵問題，例如鞋類訂單更多，交貨時間更短。此外，在中美貿易戰浪潮過後，發展中國家的勞動力成本呈上升趨勢。因此，製鞋業必須專注於快速響應訂單變化，縮短交貨時間，提高效率和降低成本。
這項研究涉及價值流圖（VSM）和模擬，旨在消除浪費，減少交貨時間，提高在製品和提高工廠效率。 VSM用於描述鞋類製造系統的當前狀態。根據從觀察到的公司收集的數據，為實際生產系統建立了兩個仿真模型，其中一個模型包括結合了精益原理的牽引系統，優化了提到的因素。因此，可以評估改善因素而不會實際中斷生產。開發這些模型以詳細對比“當前”和“未來”方案，以便向管理人員說明潛在的好處，例如減少生產提前期，降低在製品庫存。該模型包括四個主要因素：（1）切割/準備和縫合之間的批量大小； （2）在裁剪/準備和縫合之間的超市規模； （3）縫合和組裝之間的批量大小（4）裁剪/準備和縫合之間的超市規模。這四個因素適用於鞋類製造系統。通過使用在三種不同佈局上運行的實驗設計和仿真優化工具來對它們進行優化。實驗的結果可以為工廠的運營經理提供信息。

關鍵字：精益生產、模擬、製鞋業

Footwear industry is rapidly growing up in recent years with expanding of many factories around the world, especially in South East Asia countries with affordable labor costs such as Vietnam, Indonesia, Myanmar, etc. These brings more and more orders are sent to factory; However, the factory have to face some critical problems as more diverse shoe type order, shorter delivery time. Moreover, the labor cost in developing countries are in uptrend after trade war wave between the US and China. Therefore, Footwear industry necessarily focus on responding order variation rapidly, lead-time reduction, increase efficiency and reduce cost.
This research involves Value Stream Mapping (VSM) and simulation which aim to eliminate wastes, reduce lead-time, WIP and improve the factory’s efficiency. VSM is used for describing the current state of footwear manufacturing system. The two simulation models are established for actual production system based on collected data from observed company and one model included pull system combined with lean principles, optimized mentioned factors. Thus, improvement factors can be evaluated without real production disruption. These models were developed to contrast “current” and “future” scenarios in detail in order to illustrate to managers potential benefits such as reduced production lead-time, lower work-in-process inventory. The model included four main factors are (1) Batch size between cutting/preparation and stitching; (2) Supermarket size between cutting/preparation and stitching; (3) Batch size between stitching and assembling (4) Supermarket size between stitching and assembling. These four factors are applied in footwear manufacturing system. These are optimized by using experimental design and simulation optimization tool, run on three different layouts. The result of experiment can contribute to information of operation managers of the factory.

Keywords: Lean Production, Simulation, Footwear Industry
 

 摘要 I
Abstract II
Acknowledgement III
Contents IV
List of Table VI
List of Figure VII
Chapter 1 Introduction 1
1.1 Background and Motivation 1
1.2 Research Objective 3
1.3 Research Method 3
1.4 Organization of Thesis 5
Chapter 2 Literature Review 6
2.1 Lean Manufacturing 6
2.2 Value Stream Mapping (VSM) 8
2.2.1 Applications and Benefits of VSM 8
2.2.2 Value Stream Mapping in Footwear industry 9
2.3 Simulation Modeling 11
2.3.1 Insight on Simulation Modelling 11
2.3.2 Simulation works in Footwear industry 12
2.4 Summary 14
Chapter 3 Problem Definition 15
3.1 Facility Description 15
3.2 Shoe Manufacturing Process 16
3.3 Shoe Production Layout 17
3.4 Shoe Model 20
3.5 Problem Statement 20
Chapter 4 Simulation Model 24
4.1 Model Assumptions 24
4.2 Level of details 25
4.3 Data collection 25
4.4 Model Specifications 26
Chapter 5 Computational Study 32
5.1 Design of Experiment 32
5.2 Experimental Results and Analysis 34
5.2.1 The Main Effects 34
5.2.2 The Interaction 39
5.1. Regression Analysis 47
5.2. Optimal Design for Footwear Production Line 51
Chapter 6 Conclusion 56
Reference 58

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