Research On Hardware Reliability Modeling And Evaluation Method Of High-speed Railway On-board Earthquake Emergency Treatment Device

As the main artery of the national economy,high-speed railways play an increasingly important role in people's daily lives.China is located in the world's two largest earthquake concentrated zones,and it is a country with severe earthquake disasters.For high-speed railways,even small-magnitude earthquakes may cause train operation safety accidents such as derailment and overturning of high-speed trains,causing casualties and economic losses.The high-speed railway earthquake earlywarning system could issue early warnings from seconds to tens of seconds before the destructive earthquake wave strikes,making high-speed trains decelerate or stop as soon as possible,which could prevent or mitigate the damage caused by earthquake disasters to railway transportation safety,avoiding major casualties and property losses,has considerable mitigation benefits.As one of the important components of high-speed railway earthquake early-warning system,once the reliability of the on-board earthquake emergency treatment device fails to meet the requirements and cause a failure,it will lead to false alarms or loss alarms of the early-warning information,which will not only cause panic among the passengers,but also cause inconvenience to driving and cause unnecessary losses,and adverse consequences.Therefore,it is an important problem that needs to be solved to model and evaluate the on-board earthquake emergency treatment device reasonably and correctly.The on-board earthquake emergency treatment device includes an on-board earthquake emergency treatment main and an on-board earthquake emergency treatment terminal.For a complex system such as the on-board earthquake emergency treatment device,it is very difficult to model and evaluate its reliability by conventional methods because of its extremely high reliability and few samples that can be used for testing,and almost no failure data generated during the test.According to the respective characteristics of the on-board earthquake emergency treatment device and its components,the on-board earthquake emergency treatment terminal was considered as an unrepairable unit and the on-board earthquake emergency treatment main a repairable system in this thesis,and the related reliability index were obtained respectively.At the same time,the on-board earthquake emergency treatment device was regarded as a complex system,and the reliability index was obtained by fusing the reliability-related index of the on-board earthquake emergency treatment terminal and the on-board earthquake emergency treatment main.The main content and results of this thesis were as follows:(1)The on-board earthquake emergency treatment terminal was considered as an unrepairable unit,and its reliability was modeled and evaluated: In order to solve the limitation of a small number of on-board earthquake emergency treatment terminal used for testing,and with the increase in product complexity and product reliability,the failure possibility of on-board earthquake emergency treatment terminal was becoming smaller and smaller,which leads to the disadvantage of limited reliability data obtained only from a laboratory test or field test.In this thesis,the related content of the similarity theory and the Bayesian method are used to find the posterior distribution of the on-board earthquake emergency treatment terminal.Through the inheritance factor,the data of the laboratory test and the field test were fused to obtain the reliabilityrelated index of the on-board earthquake emergency treatment terminal.The method used in this paper fully considers the similarities and differences between laboratory tests and field tests,and made full use of the information of each test stage of the onboard earthquake emergency treatment terminal,so it was more reasonable.(2)The on-board earthquake emergency treatment main was considered as a repairable system,and its reliability was modeled and evaluated: In order to solve the problem that the posterior distribution of the on-board earthquake emergency treatment main was complicated and difficult to calculate,firstly a hierarchical Bayesian model of the reliability of the on-board earthquake emergency treatment main was established in this thesis,and then Markov chain in the random process was applied to Monte Carlo simulation,and the Gibbs sampling method was used to obtain a sample of the posterior distribution of the parameters,and then the posterior estimated value was obtained.This made the final result not only more "safe" than the result obtained by the ordinary Bayesian method,but also solved the problem that the posterior distribution was complicated and difficult to calculate.(3)The on-board earthquake emergency treatment device was considered as a complex system,and its reliability was modeled and evaluated: Since the on-board earthquake emergency treatment device was composed of on-board earthquake emergency treatment terminal and on-board earthquake emergency treatment main,considering that it was composed of different components,this thesis introduced the concept of weights in the process of the fusion of reliability index of different components,and uses expert information fusion based on D-S evidence theory.Compared with other methods for determining weights,in the process of determine weights of on-board earthquake emergency treatment main and on-board earthquake emergency treatment terminal by using D-S evidence theory,the uncertainty of the information provided by different experts had been fully taken into account,so that the uncertainty was continuously reduced in the process of information fusion.