Improved Response Surface Method Based on Linear Gradient Iterative Criterion

Table 6

Calculation results of example 4.

Used method	Reduction coefficient	Iteration times	Failure probability	Reliability index	Relative error (%)
Monte Carlo method	—	—	0.0048	2.5911	—
Traditional response surface method	—	10	0.0031	2.7403	5.76
The proposed method	0.01	5	0.0033	2.7118	4.66
	0.05	3	0.0033	2.7118	4.66
	0.2	3	0.0033	2.7118	4.66
	0.4	4	0.0033	2.7118	4.66
	0.6	5	0.0033	2.7203	4.99
	0.8	5	0.0032	2.7221	5.06