應用精實六標準差改善流程週期效率

An Application of Lean Six Sigma for Improving the Process Cycle Efficiency: A Case Study

吳政諭(Cheng-Yu Wu)

指導教授 ： 蘇朝墩

國立清華大學/工學院/工業工程與工程管理學系/碩士(2007年)

https://doi.org/10.6843/NTHU.2007.00030

摘要

六標準差是一套結構化的品質改善方式，精實生產是一個可以大幅消除浪費、加速流程時間的思考模式。兩者結合而成的精實六標準差是一套有系統的邏輯思考模式，可協助企業達到品質提升、消除浪費以及流程加速的目的。在台灣普遍為中小型企業之經濟型態下，一般都受限於資源，而無法像摩托羅拉或是奇異等公司般透過六標準差改善專案大規模的改變公司的經營型態。因此，一個容易使用且方便的改善方法對於這些企業而言，往往列為優先考量之重點。本研究希望透過精實六標準差以簡易的方法，結合運用流程週期效率以及流程週期效率損失的觀念，迅速的找出流程之問題所在，並且透過「精實思考」模式提出改善問題的方案，以提升流程週期效率。
　　本研究嘗試發展一精實六標準差流程改善程序，利用價值流程圖之繪製、運用流程週期效率損失數據、加值分析以及真因分析等精實與六標準差之工具，來對流程作出改善。本研究方法運用於N大學圖書館，以流程週期效率為指標，展示經過精實六標準差處理之後，流程週期效率由0.907%上升至1.48%。以易用性與執行效率來看，改善結果有突出之表現。

關鍵字

六標準差 ； 精實思考 ； 精實六標準差 ； DMAIC ； 流程週期效率

並列摘要

Six Sigma is a quality improvement approach. Lean production is a thinking mode that can be used to banish waste and accelerate process cycle time. Lean Six Sigma (LSS) combining Lean with Six Sigma is a logical and systematical management system which can help an enterprise to achieve high quality, high process efficiency and banish waste. In Taiwan, most enterprises are considered as small and medium enterprises, and thus their resources are restricted. For these reasons, it is difficult for the Taiwanese enterprises to improve their process by employing a huge and complex Six Sigma project, like GE or Motorola. What they need is an easy and convenient tool for the process improvement. This study suggests that process cycle efficiency (PCE) and process cycle efficiency destruction (PCED) can be used in LSS to quickly evaluate the performance of process.
This study attempts to develop a LSS process improvement procedure. The value stream map, PCED, value-added analysis and the tools of LSS will be employed in the procedure. A case study of the process improvement in the N university’s library is demonstrated to illustrate the effectiveness of our proposed procedure. The results show that the PCE of the process increases from 0.907% to 1.48%; this confirms the practicability and contribution of this study.

並列關鍵字

Six Sigma ； Lean ； Lean six sigma ； DMAIC ； Process cycle efficiency