Papers by Keyword: Data Uncertainties

Abstract: The risk- and condition-based dynamic inspection proposed to decrease losses and costs caused by accidents which is not only a decision-making and optimal method for inspection strategies, but is also a soft measurement system for fixed equipment safety status. In the risk- and condition-based dynamic inspection method, data collection is standardized to decrease the impact of personal factors on the data. Moreover, a procedure in which experts approve the data collected from plants is supplemented to amend error and supplement omission of data in time. A relevant inspection strategy is adopted based on the different damage types and its initiation and growth for the aspect of inspection decision-making. In the meantime, the cost-risk efficiency of the inspection is regarded as an objective function to optimize inspection strategies according to the risk status of equipment. Finally, a model is established to assess the frequency of in-service inspection and ensure equipment safety during the end of equipment life based on the fitted linear relationship between the corrosion rate and stress energy.

Abstract: We present a second order approximation for the robust counterpart of general uncertain nonlinear programs with state equation given by a partial di erential equation.We show how the approximated worst-case functions, which are the essential part of the approximated robust counterpart, can be formulated as trust-region problems that can be solved effciently using adjoint techniques. Further, we describe how the gradients of the worst-case functions can be computed analytically combining a sensitivity and an adjoint approach. This methodis applied to shape optimization in structural mechanics in order to obtain optimal solutions that are robust with respect to uncertainty in acting forces. Numerical results are presented.

Abstract: Architectural heritage is a resource and a fundamental part of the cultural European background; it also causes concern, due to the huge investment needed to maintain it, or even to repair it after environmental injuries. The Author is general coordinator of an Italian National research project aimed to formulate new guidelines for structural health monitoring and survey of historical and monumental structures. The Project programme traces a general strategy to build maintenance related monitoring procedures, to face the problems of data uncertainties, to propose robust approaches. This paper shows the general path traced for that project, just now at its start-up phase, but the main attention is addressed to the robust approaches to dynamic testing and model updating.