Repair Discipline Research Articles

Performance Analysis of Embedded System with Failure Interaction and Repair Discipline Using Copula

Performance Analysis of Embedded System with Failure Interaction and Repair Discipline Using Copula

Dynamic Analysis of the Multi-state Reliability System with Priority Repair Discipline

Dynamic Analysis of the Multi-state Reliability System with Priority Repair Discipline

The establishment and development of wound repair discipline in China.

With the acceleration of population aging and the changes of disease spectrum, the number of wound patients has increased annually in the past 20 years, which has become a major problem in terms of China's medical and health work. To address this challenge, the National Health Commission of China issued a notice in November 2019, requiring qualified medical and health institutions to establish wound repair departments to strengthen the standardized diagnosis and treatment management of various wound patients. This article introduces the establishment process of the wound repair discipline in China, as well as the practice and experience of building a high-level wound repair department in Chinese hospitals, hoping that it can be used for reference by peers.

Dynamic analysis of a complex system under preemptive repeat repair discipline

This paper considers a two-unit complex system, in which one of the components has priority with preemptive repeat repair disciplines, described by partial differential equations with integral boundary conditions. First, we prove that the system has a unique nonnegative time-dependent solution by using the strong continuous semigroup theory of linear operators. Then, we obtain the exponential convergence of the time-dependent solution to its steady-state solution by means of the spectral properties of the corresponding operator. We also provide the asymptotic behavior of some time-dependent reliability indices, a numerical illustration showing the effects of various parameters on the system, and the validity of the theoretical analysis.

Performance Analysis of Complex System in Series Configuration Under Different Failure and Repair Discipline Using Copula

This paper deal with the study of reliability of a complex system consists of three subsystems, (subsystem-1, subsystem-2 and subsystem-3) connected in series configuration. The subsystem-1 has three units and working under the policy 2-out-of-3: F policy, subsystem-2 has two units in parallel configuration and is working under 1-out-of-2: G policy and subsystem-3 is connected with subsystem-2. All three subsystems are connected in series configuration. The system has two types of failure, partial failure and completely failure. It is assumed that the partial failure bring the system to degraded state, while the complete failure stop functioning in the system. All failure rates are constant and assumed to follow exponential time distribution, but the repair follow two types of distribution, i.e., general distribution and exponential distribution. It is assumed that the system in partially failed/degraded states are repaired by employing general time distribution but the completely failed states are repaired by Gumbel–Hougaard family copula distribution. The system is analyzed by supplementary variable technique. Some crucial measures of reliability such as Availability, mean-time-to-failure (MTTF) and profit analysis have been discussed. Some computations are taken as special case by evaluating Availability, MTTF and profit by taking different failure rates.

A two dissimilar unit parallel system with two phase repair by skilled and ordinary repairmen

The paper deals with the cost-benefit and reliability analysis of a two non-identical unit parallel system with two independent repairmen—skilled and ordinary. A failed unit is first attended by skilled repairman to perform first phase repair and then it goes for second phase repair by ordinary repairman. Both types of repair discipline are FCFS. All the failure and first phase repair time distributions are exponentials with different parameters whereas second phase repair time distributions are taken general. Various important measures of system effectiveness are obtained by regenerative point technique.

Availability, MTTF and cost analysis of complex system under preemptive‐repeat repair discipline using Gumbel‐Hougaard family copula

PurposeThe main aim of this paper is to improve reliability characteristics namely availability, mean time to failure (MTTF), and expected profit of a complex system.Design/methodology/approachThe paper discusses the availability of a complex system, which consists of two independent repairable subsystems A and B in (1‐out‐of‐2: F) and (1‐out‐of‐n: F) arrangement respectively. Subsystem A has two identical units arranged in parallel redundancy (1‐out‐of‐2: G), subsystem B has n units in series (1‐out‐of‐n: F) with two types of failure, namely, partial and catastrophic. Except at two transitions where there are two types of repair namely exponential and general possible. The failure and repair time for both subsystems follow exponential and general distributions respectively. The model is analysed under “preemptive‐repeat repair discipline” where A is a priority and B is non‐priority.FindingsBy employing supplementary variable technique, Laplace transformation and Gumbel‐Hougaard family copula various transition state probabilities, availability, MTTF and cost analysis (expected profit) are obtained along with steady‐state behaviour of the system. Inversions have also been carried out so as to obtain time dependent probabilities, which determine availability of the system at any instant.Originality/valueThis paper, through a systematic view, presents a mathematical model of a complex system from which the reliability characteristics namely availability, MTTF, and expected profit of a complex system can be improved.

Analysis of a Complex System Modelled by a Marked Point Process and Assuming Vacations for a Repairman

In this paper a system consisting of two subsystems A and B is analyzed. A has only one unit while B has two units, B 1 and B 2, connected in such a manner that B 2 is in hot standby with B 1. The system is modelled by a marked point process. There are two repairmen namely a supervisor and a novice. The supervisor is always present, while the novice might be in vacation. Two types of failure of the components of B are considered. The model is analyzed under “preemptive-repeat repair discipline”. By employing Laplace transformation and assuming the Gumbel–Hougaard copula, the state transition probabilities, reliability, availability and expected profit are obtained along with the steady state behaviour of the system. At the end some special cases of the system are investigated.

AVAILABILITY AND COST ANALYSIS OF A PARALLEL REDUNDANT COMPLEX SYSTEM WITH TWO TYPES OF FAILURE UNDER PREEMPTIVE-RESUME REPAIR DISCIPLINE USING GUMBEL-HOUGAARD FAMILY COPULA IN REPAIR

This paper discusses about the availability of a complex system, which consists of two independent repairable subsystems A and B in (1-out-of-2: F) and (1-out-of-n: F) arrangement respectively. Subsystem A has two identical units arranged in parallel redundancy (1-out-of-2: G), subsystem B has n unit in series (1-out-of-n: F) with two types of failure, viz., partial and catastrophic. Except at two transitions where two types of repair namely exponential and general possible all other transitions have single possibility between any two states. The failure and repair time for both subsystems follow exponential and general distributions respectively. The model is analyzed under "preemptive-resume repair discipline" where A is considered to be in priority while B is non-priority. By employing supplementary variable technique, Laplace transformation and Gumbel-Hougaard family copula various transition state probabilities, availability, Mean Time to Failure (MTTF) and cost analysis (expected profit) are obtained along with steady-state behaviour of the system. Inversions have also been carried out so as to obtain time dependent probabilities, which determine availability of the system at any instant. At last some special cases of the system have been taken.

Reliability and availability analysis of Manhattan street networks

A Manhattan street network (MSN) is a regular, two-connected local area network. It has multiple paths between each pair of nodes that improve the reliability and throughput relative to single-loop networks. The authors evaluate reliability for accurate and approximate MSN models. Via both simulation and theoretical analysis, they show that there is little difference between the exact and approximate models. Because it is not practical to calculate the reliability for either model for large networks, simple upper and lower bounds are developed. They also determine the availability of MSNs for several repair disciplines for servicing failed links. Approximate Markov chain models for two different smart repair discipline models are analyzed. It is shown that the smart repair disciplines provide significant improvements in availability over the simple FCFS discipline, and simulations with confidence intervals are provided.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Availability of the system with general repair time distributions and shut-off rules

A model which has main and secondary subsystems subject to shut-off rules is considered. In this model, the system has a single repair facility. The repair discipline that the main subsystem has the pre-emptive repeat priority is considered. Constant failure rate and general repair time distributions are assumed. The system availability is obtained by using the linear ordinary differential equation method and supplementary variable technique.

Availability for 2/n: F and secondary subsystems with general repair-time distributions and shut-off rules

The model which main 2/n: F and secondary subsystems subject to shut-off rules is considered. In this model, the system has single repair facility. The repair discipline that the main subsystem has the preemptive repeat priority is considered. Constant failure rate and general repair-time distribution are assumed. The system availability is obtained by using linear ordinary differential equation method and supplymentary variable technique.

MTSF and availability analysis of a complex system composed of two subsystems in series subjected to random shocks with single repair facility

The present paper deals with a complex system consisting of two subsystems connected in series with a single repair facility. Subsystem S 1 consists of two units connected in standby redundancy while the other subsystem S 2 has a single unit. The method of the regenerative point technique with Markov-renewal process differing by the failure and repair discipline is used to obtain the various characteristics of the system.

A complex system having four types of components with pre-emptive repeat priority repairs

A parallel redundant complex system having pre-emptive repeat repair discipline is considered in which the pre-empted unit of lower priority class joins the service only when all units of higher priority class in service or waiting have been served. The problem is solved with the use of Laplace transforms and generating function techniques.

The 〈G/M/r/FIFO〉 Machine-Interference Model with State-Dependent Speeds

This article treats a version of the multiple machine-interference problem with r operatives under FIFO repair discipline. The running times of machine i are supposed to be identically and arbitrarily distributed random variables with density function fi(x), i = 1,…, n. The repair times of all machines are assumed to be identically and exponentially distributed random variables with mean 1/μ. The paper provides the main steady-state operational characteristics of the system when the running and repair speeds are dependent on the number of machines in working order.

Reliability analysis of a series-parallel system under different repair disciplines

In this paper we investigate a system composed of two subsystems connected in series with a single repair facility. One subsystem is K-out-of- N: G, while the other consist of several different units connected in series. The method of the supplementary variable in two models differing by the repair discipline is used to obtain the availability of the system. By making suitable transformation the reliability and the mean time to system failure (MTSF) can be deduced from the availability function.

Reliability of a complex system under pre-emptive repeat discipline

In this paper we investigate a system, composed of two parallel subsystems, connected in series with a single repair facility. The failure times are exponentially distributed, whereas the repair times are distributed quite generally. The repair discipline is of pre-emptive repeat type. We obtain the following results: Laplace transform (L-T) of the pointwise reliability, L-T of the pointwise availability, the mean time to system failure and the steady state availability.

Reliability and maintainability of a multicomponent series-parallel system with simultaneous failure under preemptive repeat repair discipline

This paper considers a system consisting of two subsystems connected in series with a single repair facility. One sybsystem is K-out-of-N:G system consisting of N identical units, while the other consists of M different units connected in series. The life-times of the active units depend on each other in having simultaneous failure of all the operating units and repair times are distributed quite generally. The system breaks down if more than (N−K+1) units in parallel group are simultaneously in the failed states or if any failure occurs in the series group or if simultaneous failure occurs. The availability and reliability function of the system are obtained simultaneously. Explict expressions for the steady state availability of the system and the mean time to the first system failure are obtained.

A parallel redundant complex system with two types of failure under preemptive-repeat repair discipline : P. P. Gupta and S. C. Agarwal. Microelectron. Reliab.24, 395 (1984)

This paper deals with the cost—benefit analysis of a single-server two-unit cold standby redundant repairable system subject to inspection. An inspection policy model is considered in which the failure of a unit is detected by inspection only but system failure is detected instantaneously without inspection. The failure time of a unit is assumed to be exponentially distributed with parameter λ. Initially, a unit is switched on and the other one is kept as cold standby. The system breaks down if a unit fails while the other is still under repair. In this paper, the system is characterised by the probabilities of its being in the up or the down state. Integral equations are set up for these probabilities by identifying suitable regenerative epochs. Laplace transform technique is employed to solve these equations. System characteristics, namely:1.pointwise availability of the system during (0, t2.s-expected up-time of the system in (0, t3.s-expected busy-period of the service facility in (0, t4.steady-state availability of the system;are obtained to carry out the cost—benefit analysis. Numerical results pertaining to three particular cases are also presented.

A parallel redundant complex system with two types of failure under preemptive-repeat repair discipline

This paper presents the availability analysis of a complex system, which consists of two s-independent repairable subsystems A and B in series (1-out-of-2: F). Subsystem A has two identical units arranged in parallel redundancy (1-out-of-2: G), sub-system B is a single unit with two types of failure, viz., partial and catastrophic. There is only one repair facility, which is always available. The failure and repair times for both subsystems follow exponential and general distributions respectively. The model so developed is analysed under “preemptive-repeat repair discipline”. By employing supplementary variable technique Laplace transforms of various probability states are obtained along with steady-state behaviour of the system. Inversions have also been carried out so as to obtain time dependent probabilities, which determine availability of the system at any time.