電腦控制系統之限制的產生

Constraint Generation for Computer-Controlled Systems

劉光桓(Kuang-Huan Liu)

指導教授 ： 范金鳳

元智大學/資訊學院/資訊工程學系/碩士(2006年)

摘要

在軟體開發的過程中，適當的限制(constraint) 可以降低系統運作的風險，特別是針對安全關鍵計算系統而言更顯重要。但過去限制的產生往往沒有系統化的方式，大多為人為考量。因此本論文發展了一套有系統的方法，以從規格中找出適當的限制。在現今的軟體開發流程中，主要的物件導向軟體其規格與設計都是以UML來撰寫，也因此本研究提供了一套有系統的方法，可以從UML圖形中直接找出規格上有的限制，或者間接由圖型中萃取出系統間相關的可能限制。

另外對於故障樹的安全分析方面，以往通常只能夠主觀的建構，無法有系統化的分析。本論文則提出了利用狀態圖或順序圖的方式，有系統的產生故障樹。並且我們結合了危險與操作性分析(HAZOP)的技術，讓故障樹的葉節點能夠充分的針對不同的應用系統，做出更適合的分析，以得到適當的限制。

綜合來說，本論文的主要貢獻為提供一套有系統的方法，從UML圖形中直接找出系統內的限制，或間接利用我們提供的填表及提示，來找出系統限制。另外利用從狀態圖或順序圖所系統化產生的故障樹，結合HAZOP方法進行分析，可以得知哪些限制的重要性較高，需要更加注意防範。

關鍵字

限制 ； UML ； 故障樹

並列摘要

Constraints can be used to check whether specified relations among variables are held at run time so as to detect potential incorrect situations. Thus proper constraints can reduce the risk of operation, especially in the safety critical computing systems, but it lakes a systematic way to produce constraints in the past. So we developed a set of systematic methods in order to extract effective constraints from UML specifications. Besides, negate the leaves of fault trees may generate safety-related constraints.

In the past, the fault trees are usually built subjectively. We have designed a systematic way to utilize the state diagram or the sequence diagram to construct fault trees. And we combine the HAZOP technology that can help us to do more flexible analysis for fault trees against different application systems.

In one word, the main contribution of this thesis is to develop a systematic method to construct constraints either directly from the UML diagrams or indirectly provide guidelines and forms for specifying constraints. Also have designed systematic method to construct fault trees from state diagrams or sequence diagrams for constraint generation.

並列關鍵字

constraint ； UML ； Fault tree

參考文獻

[1] Martin Fowler, “UML Distilled: A Brief Guide to the Standard Object Modeling Language,” Third Edition, Addison Wesley, 2003.

[3] Soon-Kyeong Kim and David Carrington, “A Formal Object-Oriented Approach to defining Consistency Constraints for UML Models,” ASWEC 2004

[5] Stephan Flake and Wolfgang Mueller, “Specification of Real-Time Properties for UML Models,” IEEE Proceedings of the 35th Annual Hawaii International Conference, pp. 3977-3986, 2002

[6] B. Litvak, et al., “Behavioral Consistency Validation of UML Diagrams,” 1st International Conference on Software Engineering and Formal Methods,

pp. 118-125, 2003