| 摘要 |
<p>PURPOSE:To speed up the decision of abnormality and to execute suitable abnormality diagnosis even at the time of process variation by adaptable controlling a threshold for the abnormality decision in accordance with the process variation. CONSTITUTION:An abnormality diagnosis processing part 5 forecasts the internal state of the process on the basis of procedure knowledge stored in a rule type data base 8 by referring a boundary value sent as a process signal 2 and a frame type data base 7. Although abnormality is decided by comparing the forecasting value with a measured value (a really measured value), the threshold is adjusted in accordance with the degree of variation of a process state at the time of varying the process state. Thus, the internal state of the process is forecasted and the threshold value for abnormality decision is suitably determined (adjusted) in accordance with the state of the process. Consequently, suitable abnormality diagnosis can be attained even at the time of process variation.</p> |
