METHOD FOR CONSTRUCTING KNOWLEDGE BASE AND FAULT DIAGNOSTIC METHOD BY KNOWLEDGE BASE

PURPOSE:To easily construct a large scale fault tree and to make possible high-speed infererace by constructing a knowledge base based on separated/ hierarchized fault trees. CONSTITUTION:Overlapping fragmentary knowledge is made common as an overlapping tree group, a high-order tree group which is a source fault tree group and a low-order tree group made common as the overlapping tree group are separated/hierarchized and the knowledge base is constructed based on the separated/hierarchized fault trees. Also, in the case of linking the separated/ hierarchized tree groups with the prescribed event of the source fault tree group, a degree for contributing to abnormal spread is different depending on the event (a connection point). Thus, an abnormal degree transfer coefficient betais made definable as a coefficient for indicating the abnormal spread degree of the low-order tree group toward the connection point in the high-order tree group. Thus, even in the case of performing inference by separating/hierarchizing the source fault trees which were present in a same space and linking them thereafter, the interference with high probability is made possible.