Preposterior Analysis Considering Uncertainties and Dependencies of Information Relevant to Structural Performance

Abstract

A modified general framework of preposterior analysis is proposed here, which takes the uncertainties and dependencies associated with the information relevant to structural performance into account, to provide a sound basis for decision making. The information that we collect to update our knowledge of structural performance forms the core of preposterior analysis. It normally is not perfect and dependent on each other. Special emphasis is placed on the identification of the potential sources of uncertainties and dependencies of the information samples. The proposed framework is formulated with the consistent representation of such uncertainties and dependencies. The framework’s application is illustrated through an example of the update of the knowledge about the condition state of gas turbine engine components. The potential uncertainties and dependencies associated with future samples of the information relevant to the flaws of the engine components are presented, and further, their effects on the update of knowledge of the components’ state are investigated.