General Repair Time Research Articles

A Repairable Multistate Device with General Repair Time

This paper deals with a repairable multistate device with general repair time distribution. The Laplace transforms of state probability for such a device are obtained and a particular case is discussed.

一般分布をもつ2-ユニット並列システム

This paper considers a two-unit paralleled system with general failure time and repair time distributions. The equations governing the behaviour of the system, without using regenerative (or cyclic) nature, have been derived by employing the method of supplementary variable. Then the problems of calculating the Laplace transform of the reliability of the system and the mean time to the first system failure are reduced to that of solved a well-known Fredholm integral equation, depending on the pdf's of the failure and repair time of units. In addition, the probability that repairman is idle at time t, the expected total idle time of repairman during the interval (O,t] , and the expected number of repair until the system failure occurs are shown.

Unavailability of components with inspection and repair

A general set of integral equations and solutions have been obtained for the unavailability of standby components. The model uses general failure time, test duration and repair time distributions. Random failures as well as contributions from human testing errors and true demands have been taken into account. Optimal testing/inspection intervals have been obtained for practical inspection policies.

Cost Analysis for 2-Unit Systems

For a 2-unit system with general repair and failure time distributions, the net profit has been studied as the difference between functions of the uptime and downtime. The mean number of products manufactured is also given.

Number of Repairs for a 2-Unit System

The number of repairs upto time t for a 2-unit cold-standby system with general repair and failure time distribution is studied. The number of failures upto time t is given as a dual case.

Reliability and Availability of Two General Multi-Unit Systems

This paper considers k-unit systems with repair. Reliability and availability integral equations are set up using renewal theory. This paper treats a k-unit system with s-dependent failure rate and general repair time distribution, and a k-unit cold-standby system with Erlang failure time distribution and general repair time distribution.

On expected profit in a two-unit standby system with switch failure

A two-unit warm standby redundant system with switch failure, exponential failure-time and general repair time distribution is considered. Howard's reward structure has been superimposed on the semi-Markov process generated by the system to obtain expected profit that the system earns in steady state. Effect of switch behaviour on expected profit has also been studied. Several particular cases are included

Interrupted service queueing with arrivals and departures in batches of variable size and general repair time distribution

Dans I'article on etudie le comportement transitoire d'un systeme de fils d'attente dans lequel les arrivees et les departs se present en groupes de taille variable et le service est donne sous reserve de panne. Immediatement apres une panne le systeme est soumis a une reparation et le service recommence aussitot la reparation effectuee. Le temps de service et le temps de remise en route du systeme sont exponentiellement repartires. LAPLACE des fonctions generatices de la probabilite de la longueur de la file d'attente. Enfin quelques cas particuliers sont discutes.

Interrupted service queueing with arrivals and departures in batches of variable size and general repair time distribution

Interrupted service queueing with arrivals and departures in batches of variable size and general repair time distribution

Reliability Analysis of an n-Spare System with a Single Repair Facility

The reliability of standby systems with repair is investigated using semi-Markov processes. The systems are composed of n + 1 identical units having an exponential failure time distribution and of a single repair facility having a general repair time distribution. For these systems, the Laplace-Stieltjes transform of the system failure time distribution is derived in the form of generating functions. For indefinitely large n, asymptotic formulae of the mean time to system failure (MTSF) and limiting distributions of the system failure time are given. Under certain conditions, the system failure time distribution is shown to tend to be exponential as n increases. Numerical examples show that the asymptotic formulae of MTSF are good approximations, even for small n. The results can also be applied to the first passage time problem of the maximal queue size in the system M/G/1.

Availability of an n-Spare System with a Single Repair Facility

The availability of a repairable system having one operating unit supported by n standby units is analyzed. The units have an exponential failure time distribution and the failed units are repaired, one at a time, with a general repair time distribution. An asymptotic formula of the stationary availability is derived, and is shown to give exact results for exponential repair times. Numerical examples show that the asymptotic formula gives a good approximation even for small n.

Complex system reliability with general repair time distributions under preemptive resume repair discipline : P. P. Gupta. Microelectron. & Reliab.12, 351 (1973)

Complex system reliability with general repair time distributions under preemptive resume repair discipline : P. P. Gupta. Microelectron. & Reliab.12, 351 (1973)

Complex system reliability with general repair time distributions under preemptive repeat repair discipline : P. P. Gupta. Microelectron. & Reliab.12, 145 (1973)

Complex system reliability with general repair time distributions under preemptive repeat repair discipline : P. P. Gupta. Microelectron. & Reliab.12, 145 (1973)

Complex system reliability with general repair time distributions under preemptive resume repair discipline : P. P. Gupta. Microelectron. & Reliab.12, 351 (1973)

Complex system reliability with general repair time distributions under preemptive resume repair discipline : P. P. Gupta. Microelectron. & Reliab.12, 351 (1973)

Complex system reliability with general repair time distributions under head-of-line-repair-discipline

The behaviour of a complex system having “ N” components in series, say class L 1 and M identical components in parallel redundancy say class L 2, has been investigated. It has been assumed that the repair of the failed components in the classes L 1 and L 2 is carried out under the “Head-of-Line-Repair-Discipline”. Laplace Transforms of various state probabilities, viz. the system is in normal efficiency, operable state, reduced efficiency and in down state, have been obtained. In the end, asymptotic behaviour of the complex system, has also been examined.

Complex system reliability with general repair time distributions under preemptive resume repair discipline

The operational behaviour of a Complex System having “N” components in class L1 connected in series and “m” identical Components in class L2 in parallel redundancy has been investigated. It has been assumed that a failure in L1 brings about the complete break-down of the system whereas a failure of two components in class L2 causes the system to work in a state of reduced efficiency. The repair of the failed components in class L1 and L2 is carried out under the Preemptive Resume Repair Discipline.(5) Laplace Transforms of various state probabilities, viz. the system is in up state, reduced efficiency state and down state, have been obtained. In the end, asymptotic behaviour of the complex system, has also been examined.

Reliability of an Independent Component, s-Spare System with Exponential Life Times and General Repair Times

Reliability of an Independent Component, s-Spare System with Exponential Life Times and General Repair Times

Reliability of an Independent Component, s-Spare System with Exponential Life Times and General Repair Times

In this paper, the reliability of a system with N independent components supplied with a pool of s spares is investigated. The components have an exponential life time distribution and the failed components are repaired, one at a time, with a general repair time distribution. Numerical results are presented for the mean time to system failure (system is said to fail when a component fails with no spare available) and the reliability of the system in some special cases of interest.

Bounds on the availability function

AbstractThis paper gives bounds on the availability function for an alternating renewal process with exponential failure and general repair times. A bound on the error is also given. Several of the bounds with greatest practical consequence are worked out and illustrated. Repair distributions for which a lower bound on availability is easily computed are gamma (integer shape parameter), log normal, and Weibull. Finally, some simulation results for log normal repair versus gamma repair are given.

Complex system reliability with general repair time distributions under preemptive repeat repair discipline

The behaviour of a complex system having “ N” components in series in class L 1 and “ m” identical components in parallel redundancy in class L 2, has been investigated. It has been assumed that a failure in L 1 brings about the complete break-down of the system whereas the failure of any two components of class L 2 causes the system to work in a state of reduced efficiency. The repair of the failed components in the class L 1 and L 2 is carried out under Preemptive Repeat Repair Discipline (5). Laplace Transforms of various state probabilities, viz. the system is in up state, reduced efficiency state and down state, have been obtained. In the end, asymptotic behaviour of the complex system, has also been discussed.