化工过程实时故障诊断专家系统的研究与开发

讨论了复杂化工过程实时故障诊断专家系统的设计与实现。对于该系统的系统结构、知识库结构以及推理机的设计进行了详细介绍。尤其是讨论了一种新的知识规则冲突消解策略——前提排序策略以及内存知识库中知识规则选择策略。并以润滑油生产过程为例,讨论了系统的故障诊断过程。实际应用表明,该系统能够及时、迅速地对故障做出响应,满足了生产需求。     

故障诊断中知识模块的应用研究

研究了知识模块在开发故障诊断专家系统中知识库的作用和过程,介绍了单级齿轮传动箱通过润滑油分析进行故障诊断的知识模块,针对实践中应用效果作了讨论。     

专家控制系统的知识库维护

专家系绕的知识获取和表示一向是专家系统开发的“瓶颈”,而知识库的维护在大型专家系统中所占的地位更是不可忽视,实时专家系统作为专家系统的一个颇有前景的研究方向,对知识库的维护又提出了哪些新的要求呢?本文试图通过减压精馏过程智能多变量控制系统(DIMCS)~*的知识库维护,探索实时专家系统中从知识表示、知识库组织到一致性维护等一系列技术的实现方式。     

基于EBL的过程故障诊断专家系统

建立了基于EBL的学习模型来完善知识库的过程故障诊断专家系统。同时，在获取新知识后对知识库进行维护，示例表明：该专家系统可较好地对过程进行故障诊断。     

基于CLIPS的某型航空发动机故障诊断专家系统知识库构建

该文针对某型航空发动机故障诊断专家系统的知识库构建开展研究工作。为解决传统故障诊断知识库构建方法复杂及开发不便的问题,该文提出了一种新的知识库开发方法。根据因果分析法得到发动机故障诊断的故障树;再利用数据抽取和知识抽取,对事实表和规则表进行了表示,并结合专家系统开发工具CLIPS实现了对某型航空发动机故障诊断专家系统的知识库的开发。该方法所构建出来的知识库满足航空发动机故障诊断专家系统的需要,而且便于知识的扩充、修改和维护。     

知识库的维护及其PROLOG实现

专家系统的广泛应用,迫切需要较完善的知识库维护方法。本文讨论了Horn短句知识库协调性维护的有关问题,并借助于归结原理和Kowalski元谓词demo的概念,提出了一种可用于专家系统知识获取过程的知识库协调性维护的方法。该方法已在IBM PC/XT上用PROLOG语言实现。     

卫星接收故障诊断专家系统的研究

文章分析了卫星接收系统的故障机理,研究了基于故障树的专家系统推理机的实现,提出了一种卫星接收故障诊断专家系统的设计思想及实现方法。推理过程以正向推理技术为主,应用二叉搜索树建立故障树,采用产生式表示法表示事实知识和规则知识,应用数据库作为知识库,构造了卫星接收故障诊断专家系统,用于对实时卫星接收过程的故障判断,指导操作员排疑解难。     

塞拉门故障诊断专家系统知识库设计与实现

根据塞拉门的故障特点,应用专家系统与数据结构的有关知识和面向对象的设计方法,论述了塞拉门故障诊断专家系统知识库的设计与实现过程;该知识库提出将设计知识与诊断知识结合,利用可靠性分析中FMEA表的分析结果来自动构建诊断知识库,采用了基于产品结构树的知识组织方法存储知识,提高了塞拉门系统故障诊断效率,为故障诊断专家系统的知识库设计提供了一种科学有效的方法.     

实时故障诊断专家系统知识库的建造

知识库是专家系统的核心部件,知识库的建造质量直接决定着专家系统解决实际问题的能力,因而,建造知识库是建造专家系统的关键工作。该文介绍对某钢厂冷轧生产线进行状态监测和故障诊断的实时故障诊断专家系统知识库的建造过程,对研究和建造类似专家系统,将具有某些实际参考价值。     

一种用于建造多塔精馏过程故障诊断专家系统知识库的方法

提出了一种用于建造多塔精馏过程故障诊断专家系统知识库的方法，该方法借助于实例，通过基于解释学习的学习模型及定量深层知识库来产生故障诊断领域知识，若用该方法建立专家系统知识库，则相应的专家系统在进行蒸馏系统故障诊断时比较快速、准确。     

Implementation of knowledge maintenance modules in an expert system for fault diagnosis of chemical process operation

Based on the authors previous work of developing an expert system for fault diagnosis of chemical processes, this paper presents principles and approaches of the knowledge base maintenance in the expert system. Development and implementation of maintenance modules for the knowledge base in the expert system for fault diagnosis of fluid catalytic cracking unit (FCCU) are reported in detail. Algorithms are proposed for integrality verification of five inconsistencies among heuristic rules: contradiction, redundancy, subsumption, circulation, and reclusion. The modules ensure the knowledge base and the expert system to work stably and efficiently. DELPHI and SQL SERVER are adopted in developing the modules. Application in FCCU fault diagnosis expert system shows that the modules work rationally and efficiently with user-friendly interface, besides its strong interactive feature and better performance of the expert system. The modules have been in continuous use in the expert system of fault diagnosis of FCCU installation in a refinery for the last two years.     

无人机飞控系统故障诊断专家系统设计

针对无人机飞控系统的特点和维护要求,本文介绍了MBIT故障诊断专家系统的设计思路和实现方法,构建了无人机飞控系统故障诊断专家系统的体系结构,深入研究了如何建立故障知识库,制定推理机制,组建综合数据库和故障解释等问题。并结合某型号给出了具体的示例。在工程实际应用过程中,可以利用本系统对无人机飞控系统进行有效维护。     

机车110V充电装置实时故障预警系统研究

110V充电装置作为机车的一个重要部分,其性能的好坏直接影响到机车的运行。本文以专家系统及故障树理论为基础,进行机车充电装置实时故障预警系统的研究。基于专家系统的故障诊断及预警方法进行分析研究后,将其应用到充电装置的针对预警中,建立了充电装置的故障树、知识获取、知识表示、故障预警推理机方法。然后,建立实时验证系统验证该理论分析及方法的可行性、有效性。     

VERIFICATION OF QUALITATIVE PROPERTIES OF RULE-BASED EXPERT SYSTEMS

Frequently, expert systems are developed to operate in dynamic environments where they must reason about time-varying information and generate hypotheses, conclusions, and process inputs that can drastically influence the environment within which they operate. For instance, expert systems used for fault diagnosis and fault accommodation in nuclear power plants reason over sensor data and operator inputs, form fault hypotheses, make recommendations pertaining to safe process operation, and in crisis situations, could generate command inputs to the process to help maintain safe operation. Clearly, there is a pressing need to verify and certify that such expert systems are dependable in their operation and can reliably maintain adequate performance levels. In this article we develop a mathematical approach to verifying qualitative properties of rule-based expert systems that operate in dynamic and uncertain environments. First, we provide mathematical models for the expert system (including the knowledge-base and inference engine) and for the mechanisms for interfacing to the user inputs and the dynamic process. Next, using these mathematical models, we show that while the structure and interconnection of information in the knowledge base influence the expert system's ability to react appropriately in a dynamic environment, the qualitative properties of the full knowledge-base/inference engine loop must be considered to fully characterize an expert system's dynamic behavior. To illustrate the verification approach, we show how to model and analyze the qualitative properties of rule-based expert systems that solve a water-jug filling problem and a simple process control problem. Finally, in our concluding remarks, we highlight some limitations of our approach and provide some future directions for research.     

An expert system for real-time fault diagnosis of complex chemical processes

This paper presents the development and implementation of an expert system for real-time fault diagnosis of chemical processes. The expert system is applied as a real-time computer aided decision support system, providing operation suggestions to help field operators when abnormal situations occur. The knowledge base structure, representation of knowledge, and access to expertise are technically considered. Industrial applications to the fluid catalystic cracking process in refinery indicate that the expert system diagnoses abnormal events efficiently and promptly.     

降雨量传感器的故障诊断方法研究

降雨量的测量对气象预报及防汛减灾具有重要作用,因此当降雨量传感器发生故障时需要能快速修复。而目前应用最广泛的翻斗式降雨量传感器其故障类型多样,致使故障诊断难度大。为此,本文提出一种基于故障树理论与灰色关联法的降雨量传感器故障诊断新方法,采用故障树理论及灰色关联分析法建立了专家系统,通过故障知识获取、故障树建立、灰色关联度获取、知识库构建和推理机推理设计,实现了降雨量传感器的故障诊断。试验验证表明,该方法故障诊断快速准确,实现系统自动诊断替代人工检测与排查,准确率可达到90%以上,提高了降雨量传感器的诊断与维修效率。     

Milling Fault Detection Method Based on Fault Tree Analysis and Hierarchical Belief Rule Base

Expert knowledge is the key to modeling milling fault detection systems based on the belief rule base. The construction of an initial expert knowledge base seriously affects the accuracy and interpretability of the milling fault detection model. However, due to the complexity of the milling system structure and the uncertainty of the milling failure index, it is often impossible to construct model expert knowledge effectively. Therefore, a milling system fault detection method based on fault tree analysis and hierarchical BRB (FTBRB) is proposed. Firstly, the proposed method uses a fault tree and hierarchical BRB modeling. Through fault tree analysis (FTA), the logical correspondence between FTA and BRB is sorted out. This can effectively embed the FTA mechanism into the BRB expert knowledge base. The hierarchical BRB model is used to solve the problem of excessive indexes and avoid combinatorial explosion. Secondly, evidence reasoning (ER) is used to ensure the transparency of the model reasoning process. Thirdly, the projection covariance matrix adaptation evolutionary strategies (P-CMA-ES) is used to optimize the model. Finally, this paper verifies the validity model and the method's feasibility techniques for milling data sets.     

基于C/S+B/S双模式的分布式远程诊断专家系统

分布式远程诊断专家系统（DRFDES）是故障诊断领域的发展趋势之一。为此文章深入研究了其工作原理、实现的硬软件结构及工作过程，分析了Web数据库的体系的两层C／S结构和三层B／S结构厦其在DRFDES中的优缺点，在该基础上提出了一种基于C／S和B／S混合模式的数据库体系的分布式远程故障诊断专家系统，探讨了故障诊断知识库的更新模式，并对分布式远程诊断专家系统实现的理论基础和关键技术进行了研究。