Fault diagnosis of chemical processes utilizing signed directed graphs-improvement by using temporal information

The fault diagnosis algorithms using a signed directed graph (SDG) as a model of the system is useful in the real-time diagnosis of failures that occur in chemical processes. The accuracy of the algorithm has been improved so that it can select the candidates that are most likely to be the real origin of failure, utilizing the time when the measured variables begins to show abnormality as the representation of the dynamic characteristic of the measured variable. The accuracy and speed of the improved algorithm have been examined by its application to data obtained in fault diagnosis experiments on tank-pipeline systems