手法を比較

	二次信頼性解析法 (SORM)	Response Surface Desirability Function
分野	信頼性工学	信頼性工学
系統	Process / pipeline	Process / pipeline
提唱年	1979	1951
提唱者	Bernd Fiessler	George Box and Kenneth Wilson
種類	Reliability analysis method	Optimization methodology
原典	Fiessler, B., Neumann, H. J., & Rackwitz, R. (1979). Quadratic limit states in structural reliability. Journal of the Engineering Mechanics Division, 105(4), 661-676.	Box, G. E. P., & Wilson, K. B. (1951). On the experimental attainment of optimum conditions. Journal of the Royal Statistical Society, 13(1), 1-45.
別名	SORM, Second-order approximation	RSM, Desirability function, Multi-response optimization
関連	4	4
概要	The Second-Order Reliability Method (SORM) is an extension of FORM that improves failure probability estimates by accounting for the curvature of the limit-state surface at the design point. Introduced by Fiessler, Neumann, and Rackwitz in 1979, SORM provides more accurate approximations for nonlinear failure surfaces while remaining computationally efficient. It has become the standard refinement when FORM accuracy is insufficient.	Response Surface Methodology (RSM) is a set of statistical and mathematical techniques for modeling and optimizing processes with multiple inputs (factors) and outputs (responses). The Desirability Function approach, introduced by Harrington (1965) and refined by Derringer and Suich (1980), extends RSM to solve multi-response optimization problems by combining competing objectives into a single index. This methodology is essential in product and process development where engineers must balance performance, cost, and reliability.