近年來，急診室過度擁擠是眾所皆知的問題，造成急診室過度擁擠有許多因素，過度擁擠的情況下會造成醫療品質下降，更甚者會造成醫療糾紛。為了使急診室可以降低過度擁擠狀況，目前救護車分流被認為是一個可能的解決方案，此方案將用來降低急診室過度擁擠，在醫院急診室發生過度擁擠情況下，我們可以選擇去讓即將到院的病患送往其他醫院的急診室，使得原本的急診室得已舒緩，進而平均分配地區內急診室資源。
本研究將設定在一個區域內有六間大小資源不同的急診室，而在此區域內的病患參數將藉由電腦程式設定，進行從病患出現，選擇前往醫院方式並選擇醫院，接著進入急診室，直到診療完畢離開急診室，在現實中，多數病患選擇去資源豐富的醫院，少數病患選擇去資源比較少醫院，對於此種現象進行參數設定，當開啟救護車分流後，電腦程式將以病患不同的嚴重度與不同的救護車分流策略進行模擬，記錄不同的策略對整個地區的擁擠程度所造成的影響，進而找出最佳的救護車分流策略。

Emergency department (ED) overcrowding is becoming a universal problem
worldwide which is caused by various input, throughput, and output factors.
Overcrowding deters timely delivery of health care and decreases the quality
of health care provided by EDs. Various strategies have been proposed for
relieving ED overcrowding, and ambulance/patient diversion (AD/PD) is
considered as one of the effective solutions by managing the input component.
The objective of this study is to access the effectiveness of different AD and
PD strategies on relieving overcrowding and maximizing the utility of medical
resources of several EDs in a region.

The study is conducted by discrete-event computer simulations based on a
stochastic queueing model that catches essential ED operations. The key
parameters of the model are selected based on real data of EDs of four
middle-size local hospitals and two medical centers in Tainan City. The
simulations takes into account the percentages of ambulance patients and
walk-in patients, the fact that ambulance patients tend to be sicker than
walk-in patients, and the fact that the walk-in patients are diverted on a
voluntary basis. Various scenarios are considered and different diversion
strategies are assessed by repeated simulations. The results indicate that
when the ambulance patients account for only 20\% of the total patients,
ambulance diversion alone has very limited effect on relieving overcrowding.
In this case, some less-sicker walk-in patients must also be diverted in order
to relieve overcrowding and maximize the utility of medical resources.

中文摘要 i
英文摘要 ii
目錄 iii
圖目錄 vi
表目錄 viii
第1章 緒論 1
1.1 研究背景 1
1.2 研究動機 2
1.3 研究目的 3
第2章 文獻探討 4
2.1 急診室模型 4
2.2 擁擠度指標 5
2.3 以往的醫療模擬模型 7
2.4 過去救護車分流研究 9
第3章 急診室相關 11
3.1 急診室作業流程 11
3.2 急診室模型 14
3.3 急救責任醫院 16
3.4 救護車分流 17
3.5 區域擁擠度 19
3.6 總結 20
第4章 系統模擬、物件導向、統一塑模語言與模擬程式 21
4.1 系統模擬 21
4.1.1 模擬模型 22
4.1.2 離散事件模擬 23
4.1.3 時間推進機構 23
4.1.4 離散事件模擬主要組成元件 25
4.2 物件導向 27
4.2.1 抽象概念 27
4.3 統一塑模語言 28
4.3.1 使用案例 28
4.3.2 活動圖 29
4.3.3 循序圖 29
4.4 模擬程式 30
4.5 總結 32
第5章 實驗模擬 39
5.1 參數設定 39
5.2 實驗模擬一 42
5.2.1 介紹 42
5.2.2 實驗 43
5.2.3 小結 45
5.3 實驗模擬二 45
5.3.1 介紹 45
5.3.2 實驗 46
5.3.3 小結 48
5.4 實驗模擬三 49
5.4.1 介紹 49
5.4.2 實驗 49
5.4.3 小結 51
5.5 實驗模擬四 51
5.5.1 介紹 51
5.5.2 實驗 53
5.5.3 小結 57
第6章 結論、限制與未來項目 59
6.1 限制 59
6.2 結論 59
6.3 未來展望 60
6.3.1 救護車分流的人數 60
6.3.2 熱門與冷門時段 60
6.3.3 緊急事故 61
參考文獻 62

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