Research On Multi-parameter Degradation Assessment Method Based On Copula Function

With the development of science and technology and product reliability level continues to improve,more and more high reliability and long life products have been widely used,especially in military equipment,aerospace and military fields,the reliability research of the product occupies a pivotal position.In this paper,the reliability degradation products with multiple assessment for the purpose of the study was established based on the degradation amount distribution and multivariate Wiener stochastic process based on accelerated degradation reliability model,the theoretical research and engineering practice,in order to evaluate the problems associated with multiple performance parameters to solve the reliability,provide ideas and research direction.The main research work of this article is as follows:First,introduces the basic theory of Establishing Multivariate accelerated degradation reliability model from multivariate degradation data structure,and accelerate the degradation path model,the failure distribution function and multivariate degradation reliability function,then introduce the Copula function related issues between multiple performance parameters of multivariate distribution function is established,and presented a method of three step comprehensive selection the optimal Copula function,and the correctness and applicability of the simulation case study shows that the method presented.Secondly,a multiple accelerated degradation reliability model based on the degenerate distribution is established.According to the marginal distribution function selection problem,put forward a kind of degenerate Anderson-Darling statistic data by calculating the average test and select the appropriate edge distribution function;through changing trend of drawing shape parameter and time,in order to determine the shape parameters and time stress and whether there is a relationship between,estimates of unknown parameters in the model are calculated the two step is based on the maximum likelihood estimation method,and verify the feasibility and applicability of the model with an example.Then,a multiple accelerated degradation reliability model based on the Wiener process is established.Random and nonlinear problems in the process of degradation and degradation of the product data modeling based on a nonlinear Wiener process by two yuan,will be treated as random drift coefficient coefficient is described considering individual differences between the samples,all the parameters in the model as a function of stress,the two step method of maximum likelihood estimation and the statistical regression analysis based on the combination of the evaluation estimates of unknown parameters,and through the crack propagation test verifies the correctness of the model.In the end,the reliability life of a O rubber sealing ring is evaluated and analyzed in combination with the practical application of the project.A bomb made of vulcanization of nitrile rubber O ring as the object of study,the constant stress accelerated degradation test scheme,by changing the degradation path and test after the appearance of the product,the O sealing ring degradation were analyzed,considering the difference of sample O type sealing ring,the nonlinear two yuan Wiener process based on accelerated degradation reliability model of sealing ring of O type storage reliability life assessment.