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Points out the steadily growing role of computers in the industrial sector. Highlights some accidents involving robots and touches on safeguards which have been introduced. Presents reliability and availability analysis of a robot machine/system having a redundant safety system. Formulas for system reliability, steady state availability, and mean time to failure are developed. Selective plots of the resulting formulas are shown.

In recent years, the application of robots in different industrial sectors such as nuclear power generation, construction, automobile, firefighting and medicine, etc. is increasing day by day. In large industrial plants generally humans and robots work together to accomplish several tasks and lead to the problem of safety and reliability because any malfunction event of robots may cause human injury or even death. To access the reliability of a robot, sufficient amount of failure data is required which is sometimes very difficult to collect due to rare events of any robot failures. Also, different types of their failure pattern increase the difficulty which finally leads to the problem of uncertainty. To overcome these difficulties, this paper presents a case study by assessing fuzzy fault tree analysis (FFTA) to control robot-related accidents to provide safe working environment to human beings in any industrial plant.

Presented FFTA method uses different fuzzy membership functions to quantify different uncertainty factors and applies alpha-cut coupled weakest t-norm (Tω) based approximate fuzzy arithmetic operations to obtain fuzzy failure probability of robot-human interaction fault event which is the main contribution of the paper.

The result obtained from presented FFTA method is compared with other listing approaches. Critical basic events are also ranked using V-index for making suitable action plan to control robot-related accidents. Study indicates that the presented FFTA is a good alternative method to analyze fault in robot-human interaction for providing safe working environment in an industrial plant.

Existing fuzzy reliability assessment techniques designed for robots mainly use triangular fuzzy numbers (TFNs), triangle vague sets (TVS) or triangle intuitionistic fuzzy sets (IFS) to quantify data uncertainty. Present study overcomes this shortcoming and generalizes the idea of fuzzy reliability assessment for robots by adopting different IFS to control robot-related accidents to provide safe working environment to human. This is the main contribution of the paper.

The purpose of this paper is to evaluate various reliability metrics such as transition state probabilities, availability, reliability, mean time to failure and expected profit of two non-identical unit parallel system incorporating waiting time.

The present paper investigates the reliability of two non-identical unit parallel system with two types of failures: common cause failure and partial failure. Moreover, waiting time to repair, a significant aspect of reliability analysis, has also been incorporated. The considered system is assumed to function properly if at least one of the units is in operative mode. The present system is examined by using the supplementary variable technique and Laplace transformation.

Numerical calculation shows that the availability and the reliability of the system is minimum when the system is without partial failure and is maximum when the system is free from common cause failure. Finally, the cost analysis of the system reveals that the expected profit decreases with increase in service cost.

This paper presents a mathematical model of two dissimilar unit parallel system, through which the performance of the considered system can be improved.

This paper presents nine different methods and approaches useful for performing human reliability and error analysis in health care. These methods are failure modes and effect analysis (FMEA), root cause analysis (RCA), fault tree analysis (FTA), cause and effect diagram (CAED), hazard operability study (HAZOP), probability tree method, error cause removal program (ECRP), man‐machine systems analysis (MMSA), and the Markov method. The applications of many methods are demonstrated through nine solved examples.

The aim of the paper is to present the impact of human errors in maintenance as found in the literature in order for practitioners to be aware of their impact and develop actions to mitigate their effect.

The paper systematically categorizes the published literature and then analyzes and reviews it methodically.

Human error in maintenance is a pressing problem.

A maintenance person plays an important role in the reliability of equipment. It is also a well‐known fact that a significantly large proportion of total human errors occur during the maintenance phase. Human error in maintenance is a subject which in the past has not been given the amount of attention that it deserves. This paper will be useful to people working in the area of maintenance engineering, as it presents a general review of literature published on maintenance errors in various sectors of industry.

The paper contains a comprehensive listing of publications on the field in question and their classification according to industry. The paper will be useful to researchers, maintenance professionals and others concerned with maintenance to understand the importance of human error in maintenance.

This paper presents a review of published literature on robot reliability and safety. The literature is classified into three main categories: robot safety; robot reliability; and miscellaneous. Robot safety is further categorized into six classifications: general; accidents; human‐factors; safety standards; safety methods; and safety systems/technologies. The period covered by the review is from 1973 to 2001.

The purpose of this paper is to study reliability, availability, and mean time to failure of a repairable robot‐safety system composed of n robots, m safety units, and a perfect switch.

Generalized expressions for system state probabilities, system availability, reliability, and mean time to failure are developed. Supplementary variable and Markov methods were used to develop these expressions.

This study clearly demonstrates that backup robots, safety units, and the repair process help to improve system availability.

This study will help maintenance engineers and reliability practitioners to become aware of the combined effect of backup robots, safety units, and the repair process on the performance of the robot‐safety system. Consequently, they will make better maintenance related decisions in organizations that make use of robots.

This paper has studied the effects of having redundant robots, safety units, and the repair facilities on the performance of a robot‐safety system with perfect mechanism to turn on a safety unit. This is one of the first attempts to study the combined effects of all these factors on a robot‐safety system.

The purpose of this paper is to review maintenance strategies within the healthcare domain and to discuss practical needs as gaps between research and practice.

The paper systematically categorizes the published literature on clinical maintenance optimization and then synthesizes it methodically.

This study highlights the significant issues relevant to the application of dependability analysis in healthcare maintenance, including the quantitative and qualitative criteria taken into account, data collection techniques and applied approaches to find the solution. Within each category, the gaps and further research needs have been discussed with respect to both an academic and industrial perspective.

It is worth mentioning that medical devices are becoming more and more numerous, various and complex. Although, they are often affected by environmental disturbances, sharp technological development, stochastic and uncertain nature of operations and degradation and the integrity and interoperability of the supportability system, the associated practices related to asset management and maintenance in healthcare are still lacking. Therefore, the literature review of applied based research on maintenance subject is necessary to reveal the holistic issues and interrelationships of what has been published as categorized specific topics.

The paper presents a comprehensive review that will be useful to understand the maintenance problem and solution space within the healthcare context.

The purpose of this paper is to study the combined effect of human error, common‐cause failure, redundancy, and maintenance policies on the performance of a system composed of three‐state devices.

Generalized expressions for time‐dependent and steady state availability of a generalized maintainable three‐state device parallel system subjected to human errors and common‐cause failures are developed in the paper under two maintenance policies: Type I repair policy (i.e. only the completely failed system is repaired); and Type II repair policy (i.e. both partially and completely failed system is repaired). The Markov method is used to develop general and special case expressions for state probabilities, and system time‐dependent and steady state availabilities.

In the case of three‐state devices, it is demonstrated that by increasing the number of redundant devices in parallel do not necessarily lead to the improvement in the system availability. In fact, the availability of the system depends significantly on the dominant failure mode of the devices (i.e. short‐mode or open‐mode). When comparing the effect of maintenance policies on the system availability, it is observed that the Type II repair policy does not lead to an improvement in the system availability. Furthermore, it is observed that both human error and common‐cause failure independently lead to lower system availability.

This study will help maintenance engineers and reliability practitioners to become aware of the combined impact of redundancy, human error, common‐cause failure, and maintenance policies on the performance of the three‐state device systems. Consequently, they will make better maintenance related decisions in organizations such as oil refineries and power stations that use three state devices quite extensively.

Most of the past models have independently studied the effects of redundancy, human error, and common‐cause failure on maintainable system made up of three‐state devices. This effort is one of the first attempts to study the combined effects of all these factors in a parallel system composed of three state devices.

The purpose of this paper is to develop a new interdisciplinary methodology to estimate the life cycle cost (LCC) of complex business-to-business products in order to price different types of maintenance contracts and show the applicability of the method in a case study. LCC comprise of initial capital costs as well of operation costs including probabilistic costs (such as the costs of repairs and spare parts), which are directly linked to the maintenance characteristics of the product.

The paper proposes an integrated and practical methodology that applies different approaches from different disciplines. Therefore, exponential distributions for failure rates in subsystems, World Bank logistics factors for logistics costs of spare part handling, as well implied credit default probabilities for the counterpart risk in full service leasing contracts are applied. In order to validate the applicability of the proposed methodology to practical problems, the tool is applied in three case studies.

The results of the case studies show that this methodology can be applied to analyze LCC structures of engines operating in various regions with regard to different types of engine maintenance contracts. The results also highlight the interplay of technical as well as financial risks.

Because the literature in maintenance engineering so far either proposes general frameworks to calculate LCC or concentrates on specific aspects of LCC, the paper contributes to the literature in presenting a new interdisciplinary methodology to estimate the LCC.