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Saddlepoint Approximation for Sequential Optimization and Reliability Analysis
Journal of Mechanical Design
  • Xiaoping Du, Missouri University of Science and Technology
A good balance between accuracy and efficiency is essential for reliability-based design (RBD). For this reason, sequential-loops formulations combined with the first-order reliability method (FORM) are usually used. FORM requires a nonlinear non-normal-to-normal transformation, which may increase the nonlinearity of a probabilistic constraint function significantly. The increased nonlinearity may lead to an increased error in reliability estimation. In order to improve accuracy and maintain high efficiency, the proposed method uses the accurate saddlepoint approximation for reliability analysis. The overall RBD is conducted in a sequence of cycles of deterministic optimization and reliability analysis. The reliability analysis is performed in the original random space without any nonlinear transformation. As a result, the proposed method provides an alternative approach to RBD with higher accuracy when the non-normal-to-normal transformation increases the nonlinearity of probabilistic constraint functions.
Mechanical and Aerospace Engineering
National Science Foundation (U.S.)
University of Missouri--Rolla. Intelligent Systems Center
Keywords and Phrases
  • Design Engineering,
  • Reliability
Document Type
Article - Journal
Document Version
File Type
© 2008 American Society of Mechanical Engineers (ASME), All rights reserved.
Publication Date
Citation Information
Xiaoping Du. "Saddlepoint Approximation for Sequential Optimization and Reliability Analysis" Journal of Mechanical Design (2008)
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