Unified Study on a Computer-Aided Maintenance System

(1)两种CUSUM方法分别为Crosier方法和Healy方法，已成功应用于具有大量噪声变量的过程监控问题。(2)提出了一种组合算法，对可能发生致命事故的设备进行预防性维修，合理选择维修周期和维修工种。(3)利用聚类和ICA技术开发了几种检测污垢或腐蚀传播的新方法。还考虑了避免设备故障的操作程序的综合。(4)建立了支持间歇工厂安全设计的风险评估体系，根据事件的严重程度和发生频率，对风险进行定性分析，明确间歇过程中可能发生的所有事故情景。(5)提出了一种利用有符号有向图搜索多故障源的算法。对该算法进行了改进，利用化学过程中状态变量间的时滞信息，得到了精度令人满意的诊断结果。该算法在催化裂化装置动态仿真中的应用验证了其有效性。(6)开发了对策规划算法，用于恢复异常情况，当找到每个候选项的共同对策时，完成故障诊断。基于高阶统计量的过程数据分析也得到了发展。(7)提出了一种确定计算机辅助维修系统中各部件活动合理分配的方法

(1) Two types of CUSUM method called Crosier Method and Healy Method have been successfully applied to process monitoring problems with a large number of noisy variables.(2) A combinatorial algorithm has been developed to select rationally periods and kinds of works for preventive maintenance of the equipment whose breakdown might give rise to a fatal accident.(3) Several novel methods to detect the propagation of fouling or corrosion have been developed by using clustering and ICA techniques. Synthesis of operating procedures to avoid faulty equipment is also considered.(4) A risk assessment system has been developed for supporting safety design of batch plants, which gives us qualitative risks based on the degree of severity and the frequency of events, as well as makes clear all accident scenarios that are likely to occur in batch processes.(5) An algorithm for searching multiple origins of failures by use of the signed digraph has been proposed. The algorithm has been improved so as to obtain diagnostic results of satisfactory accuracy using information about delays among state variables in a chemical process. The usefulness of this algorithm is demonstrated by its application to a Fluidized Catalytic Cracking Unit dynamic simulator.(6) Countermeasure planning algorithms has been developed to recover the abnormal situations in which fault diagnosis will be finished when a common countermeasure for each candidate can be found. Process data analysis based on high order statistics is also developed.(7) A method has been developed to determine rational allotment of component activities in a computer-aided maintenance system