Analysis method of step-down-stress accelerated life test with artificial immune algorithm

Maximum Likelihood Estimate(MLE) is a widely used method in the analysis of Accelerated Life Tests(ALT),while the optimization of the likelihood function is a main obstacle to the application of MLE in ALT.The common algorithm to resolve likelihood function has a strict requirement to the initial value,and is easily plunged into local optimum.In order to resolve these problems,a new analysis method,step-down-stress accelerated life test based on artificial immune algorithm,is put forward,in which artificial immune algorithm is introduced to optimize the likelihood function.The advantage of the artificial immune algorithm in the optimization of the multi-dimension complicated function is used to optimize the likelihood function.Practical example demonstrated the feasibility and effectiveness of the proposed method.Besides,since it is not needed to consult statistic tables,computer programming becomes easier,thus the method can be easily applied in engineering.