由於環境的快速變遷，讓人類的健康常常面臨極大的考驗，因而醫院的急診室常常扮演著人類生死存亡的關鍵角色，又由於醫療服務具有高度的專業性及不可替代性，使得民眾對急診室有著高度的期許與依賴，但很多醫院的急診部門仍然有病患等待過久且延誤就醫的問題，造成了許多醫療上的糾紛，而且不斷加劇上升的醫療保健費用，增加了許多醫院的負擔，使得醫療照顧品質管理形成高度風險化，因此如何在兼顧醫院的成本下改善急診室的流程，來增加病患對醫療院所的滿意度實為一重要的課題。 　　本篇論文應用統一模式語言（unified modeling language, UML）與模擬技術來探討國內醫療院所急診流程的改善方法，UML承襲物件導向分析與設計的方法，可用來作為描述模擬模組藍圖的標準模式語言，系統模擬則是許多專家學者建議使用，對於改進醫療保健為一種非常有效的工具，此研究之資料蒐集自中部的某地區教學醫院，經過電腦分析比較結果發現在不改變目前現有的資源下，適當的流程改善可以有效地降低循環時間、系統中之人數、及等待時間，達到提升醫療照顧品質，進而維持適度的醫療成本，減少醫療資源浪費的目的。

　　　　　In a rapidly changing environment, the personal health of humans is often challenged. The emergency department (ED) of a hospital is often challenged to play a role between life and death. Increasingly, patients have higher expectations of professionalism in healthcare. However, EDs in many hospitals have long waits wherein patients are sometimes not treated expeditiously. This results in malpractice suits that cause healthcare costs to be increasingly on the rise. This added burden to hospitals places healthcare quality management at high risk. Therefore, controlling costs while introducing changes in EDs in order to increase patients’ satisfaction is indeed an important issue. This research uses Unified Modeling Language (UML) with simulation techniques to study the processes of EDs in order make appropriate process-change recommendations. UML is an object-oriented analytical and programming method used to create a blueprint of a simulation model for an ED. Many researchers have suggested that system simulation is an efficient tool for improving healthcare quality. The data for this research was collected from a local teaching hospital in Central Taiwan. After computer analysis and comparison, it was found that ED processes can be improved by making certain adjustments without changing resources. Therefore, with appropriate adjustments, the cycle time, number of persons in the system and waiting time can be effectively lowered. These adjustments in turn result in increased healthcare quality, cost savings and decreased wastage of resources.