隨著網路的普及，有越來越多的應用程式改以服務的方式存在，這樣不但可以降低本地端負擔的成本，且具備了加速整合與重複使用的特點，服務導向架構(SOA)就是為了因應這類型需求所產生的，近年來相關的技術持續蓬勃發展，不僅是硬體方面效能的提升，在軟體層面也有長足的進步，舉凡(XML)平台的架構、網路伺服底層溝通的協議以及訊息包裝的標準等，都投入了相當多的學術研究和實務測試，不過值得注意的是，負責協調眾多網路元件執行邏輯的技術卻還仍舊停留在畫有向圖的階段，這是起源於當初電腦只能批次處理下的作法，而今日科技發展日新月異，平行運算、多工處理都早已是計算機系統的基本功能，面對如此的變遷，我們不得不思索現行利用有向圖來定義工作流程的方式，是否真的能有效率的處理各種網路服務流程的需求，本篇論文主要就是針對這個問題進行研究，我們試著舉出一個範例來說明，利用有向圖來處理類似的狀況是相當複雜的，就當我們試著要從邏輯觀點來解決此類問題時，卻發現了可廢止邏輯系統在處理邏輯判斷的方式與一般的程式並不相同，於是我們試圖朝著此方向來探討，但畢竟可廢止邏輯只是單純的數學理論，要將它實際套用在工作流程上其實並不容易，所以我們為此設計了一個新的系統架構，主要是藉由代理程式來輔助邏輯系統的推理，以確保流程導向的正確性。且經由實作的結果發現，我們不但可以順利的模擬出現行一般的工作流程，更有明確的數據顯示，此法運用在大部分的流程系統中是相當有效率的。

With popularization of the network, there are more and more application programs which are changed to exist in the service way. This may not only reduce the cost of local host, but has to speed up integration and reuse characteristics. Service Oriented Architecture (SOA) is produced for this type of demand.

　　In recent years the related technologies continued the vigorous development, not only the hardware aspect potency promotion, but also many progresses of software, such as the architecture of XML platform, protocol of web server engine ,the standard of SOAP message and so on, they are all put into quite many academic researches and practical tests. It's worth noting that the technology of management work flow system still remains in the directed graph stage. This stems from initially the computer only had batch processing. However, the technological progress changes every day at present, both parallel operation and multiple processing are already the basic functions of computer system. Facing the changes, we cannot but think about the directed graph work flow is really can handle each kind of demand of network service or not.

　　This paper is mainly aims at this question to conduct the research. We tried to give an example to explain the use of directed graphs to handle a similar situation is quite complex. When we tried to solve this problem from the logical point of view, we found the judgment way between defeasible logical system and general program is different, so we tried to move this direction to explore. After all, defeasible logic is simply the number of systems theory, it is not easy to apply to work processes on fact, so we devised a new system architecture which mainly through proxy program to aid the inference of logical system and this is to ensure the accuracy of process-oriented.
Through the implementation of the results, we found we cannot only simulate general work flow successfully, but also most explicit data demonstrated this way in the majority of flow systems were quite effective.

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