手法を比較

	二次信頼性解析法 (SORM)	高加速寿命試験（HALT）
分野	信頼性工学	信頼性工学
系統	Process / pipeline	Process / pipeline
提唱年	1979	1990s
提唱者	Bernd Fiessler	William Leis and others
種類	Reliability analysis method	Product reliability testing 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.	Leis, B. N., & Stephens, D. R. (2011). Reliability methodologies for structural integrity assessment. Journal of Pressure Vessel Technology, 133(5), 051204.
別名	SORM, Second-order approximation	HALT, Accelerated stress testing, HASS
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.	Highly Accelerated Life Testing (HALT) is a methodology for rapidly identifying design weaknesses and determining the margin between normal operating conditions and product failure. By applying extreme but non-destructive stress profiles (thermal, vibration, etc.), HALT accelerates the failure clock to reveal latent defects in weeks rather than years. Developed intensively from the 1980s onward and refined by practitioners in electronics and mechanical systems, HALT has become essential in accelerated product development and reliability validation.