The Research On System Fuzzy Reliabilty

Fuzziness in practical engineering widespread,and when the sample size is smaller, fuzziness in the reliability analysis play a decisive role.Fuzzy reliability analysis method based on the reality that modern engineering systems are becoming increasingly complicated,parts of the system and the level of state are required more detailed description,and people have increasingly high demands for the reliability of the system,conventional binary reliable state Design theory has not be able to meet the practical requirements.Fuzzy reliability model concentrates efforts on simulating system in these circumstances and provide a more realistic interpretation of the system.Therefore,based on the theory of fuzzy sets reliability,analysis,assessment, allocation,forecasting methods have emerged.Especially in the early reliability of complex systems design and analysis,human-computer research in the field of comprehensive reliability,and so on,fuzzy analysis method has a strong applicability.Fuzzy mathematical method essentially improved the reliability of the traditional method of limitations and inadequacies,and is an analysis method being more in line with the nature of development of things.Fuzzy reliability of the crux of the problem is how to build GM reliability of the model and to find effective algorithm for the evaluation of system performance.The results are expected to be extensively applied in the engineering system simulation and design.This analysis method is of great theoretical and has wide applications in the future.This paper studies the content of reliability theory,fuzzy math,the random process theory,and mechanical engineering project of the cross-cutting areas.It use reliability theory and fuzzy reliability theory to analyse the reliability of the large and complex system in order to establish the system model for some typical system of reliability and indicators of the reliability of the analysis and calculation methods.On the basis of previous studies in fuzzy reliability theory,we make a more in -depth study in the following aspects:(1)Fuzzy reliability model and its application.On the basis of the classical theory of reliability,we introduce the relevant fuzzy set theory,establish fuzzy reliability model of reliability basic model of the system,such as serial,parallel,the voting system,and make the relationship between modules of the system and the reliability of the fuzzy,fuzzy failure rate,fuzzy average life expectancy,and other indicators and the mathematical expression.(2)System fuzzy reliability optimization allocation model and its algorithm.We analyse the research methods of the mechanical fuzzy reliability of the design to optimize the reliability of the objective function and constraints,and discuss the principle in detail in fuzzy algorithm optimization process of the fuzzy reliability changing into the conventional algorithm.At the same time,we state the optimal design of the three basic concepts of understanding and meaning.Finally,sum up the three most common fuzzy reliability optimal allocation model and its algorithm, including the most optimal allocation fuzzy,fuzzy reliability optimize distribution and fuzzy redundancy-reliability optimization allocation model.(3)System Reliability fuzzy comprehensive evaluation model and its algorithm.On the one hand,the reliability of the system has an important impact on the distribution of the fuzzy factors to be analytical and quantitative,show up the method of fuzzy and distribution of the reliability of the system,and,finally,the fuzzy reliability allocation model of parallel and series system has been derived.On the other hand,combining the level of cut sets,fuzzy comprehensive evaluation and optimization method,we get a optimization analysis method of the reliability of the complexity of system, reliability of whose subsystem is different membership function.With the method,we at first use respectively fuzzy comprehensive evaluation to identify the level of reliability of the subsystems.Then,we use the level of cuts to determine subsystem reliability interval.Finally,we use optimization methods to analyse and make decision on the reliability of the whole system.