The repeated failures of any equipment or systems are modeled as a renewal process. The management needs an assessment of the number of future failures to allocate the resources needed for fast repairs. Based on the i...The repeated failures of any equipment or systems are modeled as a renewal process. The management needs an assessment of the number of future failures to allocate the resources needed for fast repairs. Based on the idea of expectation by conditioning, special Volterra-type integral equations are derived for general types of repairs, considering the length of repair and reduced degradation of the idle object. In addition to minimal repair and failure replacement, partial repairs are also discussed when the repair results in reduction of the number of future failures or decreases the effective age of the object. Numerical integration-based algorithm and simulation study are performed to solve the resulting integral equation. Since the geometry degradation in different dimensions of a rail track and controlling and maintaining defects are of importance, a numerical example using the rail industry data is conducted. Expected number of failures of different failure type modes in rail track is calculated within a two-year interval. Results show that within a two-year period, anticipated occurrences of cross level failures, surface failures, and DPI failures are 2.4, 3.8, and 5.8, respectively.展开更多
This paper considers a two–unit same cold standby repairable system with a replaceable repair facility and delay repair .The failure time of unit is assumed to follow exponential distribution , and the repair time an...This paper considers a two–unit same cold standby repairable system with a replaceable repair facility and delay repair .The failure time of unit is assumed to follow exponential distribution , and the repair time and delay time of failed unit are assumed to follow arbitrary distributions , whereas the failure and replacement time distributions of the repair facility are exponential and arbitrary . By using the Markov renewal process theory, some primary reliability quantities of the system are obtained.展开更多
In this paper the model of servicing machines with repairable facility is further studied.By standard conditioning decomposition argument,two reliability indices-the probability that the service facility fails at time...In this paper the model of servicing machines with repairable facility is further studied.By standard conditioning decomposition argument,two reliability indices-the probability that the service facility fails at time t and the expected number of failure occurring during（0,t] are discussed.Some important relations of them are given.Furthermore,some new reliability problems are presented and discussed as follows：1） The numbers of the service facility failures during the generalized service time and the generalized busy period;2） The asymptotic expansion of the expected failure number of the service facility during（0,t].A series of new reliability results of the service facility are obtained.展开更多
On the basis of Ref.\, the M x/G(M/G)/1 repairable queueing system with single delay vacation is discussed again. The following reliability problems of the service station are studied: (a) The probability that it fai...On the basis of Ref.\, the M x/G(M/G)/1 repairable queueing system with single delay vacation is discussed again. The following reliability problems of the service station are studied: (a) The probability that it fails at time t , i.e. its unavailability; (b) The expected failure number during the time interval (0,t\];; (c) The expected failure number during the ″server busy period″; (d) The expected downtime during the time interval (0,t\]. Some reliability results of the service station are obtained. These results would be interest to reliability analysts.展开更多
文摘The repeated failures of any equipment or systems are modeled as a renewal process. The management needs an assessment of the number of future failures to allocate the resources needed for fast repairs. Based on the idea of expectation by conditioning, special Volterra-type integral equations are derived for general types of repairs, considering the length of repair and reduced degradation of the idle object. In addition to minimal repair and failure replacement, partial repairs are also discussed when the repair results in reduction of the number of future failures or decreases the effective age of the object. Numerical integration-based algorithm and simulation study are performed to solve the resulting integral equation. Since the geometry degradation in different dimensions of a rail track and controlling and maintaining defects are of importance, a numerical example using the rail industry data is conducted. Expected number of failures of different failure type modes in rail track is calculated within a two-year interval. Results show that within a two-year period, anticipated occurrences of cross level failures, surface failures, and DPI failures are 2.4, 3.8, and 5.8, respectively.
基金Supported by the National Education Ministry for Chinese University Excellent Teachers (No.Y02012011001001) and the Academic and Technical Leader Training Foundation of Sichuan Province (No.Y02001011001003)
文摘This paper considers a two–unit same cold standby repairable system with a replaceable repair facility and delay repair .The failure time of unit is assumed to follow exponential distribution , and the repair time and delay time of failed unit are assumed to follow arbitrary distributions , whereas the failure and replacement time distributions of the repair facility are exponential and arbitrary . By using the Markov renewal process theory, some primary reliability quantities of the system are obtained.
基金Supported by the National Natural Science Foundation of China (No.70871084)the Specialized Research Fund for the Doctoral Profram of Higher Education of China (No.200806360001)
文摘In this paper the model of servicing machines with repairable facility is further studied.By standard conditioning decomposition argument,two reliability indices-the probability that the service facility fails at time t and the expected number of failure occurring during（0,t] are discussed.Some important relations of them are given.Furthermore,some new reliability problems are presented and discussed as follows：1） The numbers of the service facility failures during the generalized service time and the generalized busy period;2） The asymptotic expansion of the expected failure number of the service facility during（0,t].A series of new reliability results of the service facility are obtained.
基金the Supporing Program of the National Education Ministry for ChineseUniversity Excellent Teachers([2 0 0 0 ]65 )
文摘On the basis of Ref.\, the M x/G(M/G)/1 repairable queueing system with single delay vacation is discussed again. The following reliability problems of the service station are studied: (a) The probability that it fails at time t , i.e. its unavailability; (b) The expected failure number during the time interval (0,t\];; (c) The expected failure number during the ″server busy period″; (d) The expected downtime during the time interval (0,t\]. Some reliability results of the service station are obtained. These results would be interest to reliability analysts.
