The Development of Computer Aided Risk Assessment System and It's Application

提出了一种将知识工程应用于自动HAZOP的算法。HAZOP专家系统的开发首先需要考虑研究所需的知识类型，以及如何将这些信息纳入系统。实施HAZOP所需的知识可分为两类：(1)一般知识；(2)植物特有知识。这些知识相互作用进行HAZOP分析，通用知识由引导词、属性词(过程词)、所需操作、部件故障和故障传播模型组成，以决策表和建议操作的形式进行描述。这一知识是以独立于过程的方式发展起来的，适用于各种工艺流程图。植物特有知识包括有关材料、反应和植物结构的信息(P图和I图)。植物特有的知识因植物而异，不同的植物…用户必须提供更多的NT AN。HAZOP专家系统主要由知识库(工厂专用知识库、通用知识库)和推理机组成。用户通过指定工艺单元或管线中的工艺变量偏差，请求专家系统执行HAZOP分析。通过搜索知识库，利用关键字描述偏差，对设备的各个工艺变量进行排序学习。这种研究建立了因果方程，并开发了行动项目。原因方程描述了所考虑的偏差及其可能原因之间的逻辑关系。后果方程描述了主要设备项和工艺变量对单一偏差的响应。计算机程序将原因方程和结果方程转换为HAZOP，并在HAZOP记录表中制表。本工作的专家系统是用逻辑程序设计语言PROLOG编写的。该语言非常适合表达逻辑和执行符号操作，因此可以很好地应用于专家系统。本应用程序是在EWS环境中开发的。较少

An algorithm for application of knowledge engineering to automated HAZOP has been developed. The development of the expert system for HAZOP first required the consideration of the types of knowledge required for the study, and how this information could be incorporated into the system. The knowledge required to perform HAZOP can be separated into two types ; (1) the generic knowledge, (2) the plant specific knowledge. This knowledge interacts with each other to perform HAZOP analysis.The generic knowledge consists of guidewords, property words (process words), action required, components failure and fault propagation models, which are described in the form of decision table and suggested actions. This knowledge is developed in a process-independent manner and is applicable to wide variety of process flow sheets. The plant specific knowledge consits of information about materials, reactions, and the plant structure (P and I diagram). The plant specific knowledge varies from plant to pla … More nt an has to be provided by the user. Expert system for HAZOP consists basically of the knowledge bases (the plant specific knowledge base, the generic knowledge base) and the inference engine. The user requests the expert system to perform the HAZOP analysis by specifying a process variable deviation in a process unit or pipe line. Each process variable of equipment is studied in sequence by searching the knowledge base, using key words to describe deviations. And this search builds cause and consequence equations and develops action items. Cause equations describe logical relationships between considered deviation and its possible causes. Consequence equations describe how major items of equipment and process variables respond to single deviation. The computer program translates cause equations and consequence equations into HAZOP and tabulates in HAZOP record sheets. The expert system for this work is written in Prolog - a logic programming language. The language is excellent for expressing logic and performing symbol manipulation and hence has ready application to the expert system. The present application was developed in an EWS environment. Less