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This article considers a reliability model where the failure is due to cumulative damage exceeding a threshold level. The concept that the threshold level of cumulative damage at each arrival of shock can change based on whether the magnitude of each shock exceeds its defined threshold level is considered to compute the system reliability.

The stochastic process approach is used to obtain the cumulative damage based on Poisson arrival of shocks. The general expression for reliability is obtained using the conditional probability over each arrival of shock. The method of maximum likelihood estimation is used to obtain the estimators of the parameters and system reliability. A sensitivity analysis is performed to measure the effect of the parameter representing the rate of arrival of shock.

The maximum likelihood estimates of the reliability approach the actual reliability for increasing sample size. A sensitivity analysis study on the parameter representing the rate of arrival of shock shows that as the values of parameter increase (decrease), the reliability value decreases (increases).

Obtained a new expression for the cumulative damage–shock model and the findings are positively supported by presenting the general trend of estimated values of reliability approaching the actual value of reliability. The sensitivity analysis also genuinely supports our findings.

The purpose of this paper is to generalize Yeh and Zhang's 2004 random threshold failure model for deteriorating systems.

An N‐policy was adopted by which the system was replaced after the Nth failure.

The model was found to have practical applications in warranty cost analysis.

By identifying the instance of a shock as the failure of the system and the threshold times as the warranty period offered and changing the definition of lethal shock (system failure in this case) as the occurrence of a shock within a threshold period in our generalized model, one can study the renewing warranty cost analysis.

The purpose of this paper is to present age-based replacement models subject to shocks and failure rate in order to determine the optimal replacement cycle. As a result, according to system reliability, maintenance costs of the system are to be minimized.

First, the modeling with respect to assumptions and two major factors (shocks and failure rate) is done. Second, by using of MATLAB the optimal parameters are obtained. Finally, analysis of results and comparison of models are done.

Analysis of results shows all models provide optimal replacement cycle and at this time, cost rate of the system by considering the reliability rate is minimal. Also with an increase of one unit to two units, reliability rate increases much higher than the rate of cost.

This work provides models that in addition to considering the failure rate (internal factors), also shocks as an external factor have been considered. By considering these two factors more comprehensive and adaptable models have been proposed.

Hydraulic slide valve failure often results from competing failure modes, termed competitive failure. To enhance prediction accuracy for hydraulic slide valve remaining useful life, the authors propose a method incorporating competitive failure and Monte Carlo simulation. This method allows for more accurate prediction of hydraulic slide valve remaining useful life.

In this paper, the competitive failure mode of the hydraulic slide valve is analyzed by studying the two failure modes of the hydraulic slide valve, and the prediction of the remaining useful life of the hydraulic slide valve is studied by using the sample set generated by Monte Carlo simulation and the competitive failure joint model.

The results show that the proposed prediction method based on competitive failure and Monte Carlo simulation is more accurate than the traditional Bayesian joint model prediction method when dealing with the failure mode competition phenomenon of hydraulic slide valve.

In this paper, the remaining useful life prediction of hydraulic slide valve with competitive failure characteristics is studied, which provides a new idea for the remaining useful life prediction method.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2023-0361/

Random shocks are a leading cause of equipment failure. The shocks arise because of large variations in parameters like operating load, voltage, pressure, thermal load, hardness, contamination, tolerances on clearances and alignments, among other factors. Frequent inspections can help detect deterioration at an early stage and prevent failure. However, inspection is also expensive. The challenge is to develop a model that keeps inspection costs to a minimum while ensuring that the equipment down time is prevented or minimised. This paper first develops a model based on failure due to random shock loads, and then follows it up with a strategy for preventing or minimising such failure at optimum cost.

In some environments, the failure rate of a system depends not only on time but also on the system condition, such as vibrational level, efficiency and the number of random shocks, each of which causes failure. In this situation, systems can keep working, though they fail gradually. So, the purpose of this paper is modeling multi-state system reliability analysis in capacitor bank under fatal and nonfatal shocks by a simulation approach.

In some situations, there may be several levels of failure where the system performance diminishes gradually. However, if the level of failure is beyond a certain threshold, the system may stop working. Transition from one faulty stage to the next can lead the system to more rapid degradation. Thus, in failure analysis, the authors need to consider the transition rate from these stages in order to model the failure process.

This study aims to perform multi-state system reliability analysis in energy storage facilities of SAIPA Corporation. This is performed to extract a predictive model for failure behavior as well as to analyze the effect of shocks on deterioration. The results indicate that the reliability of the system improved by 6%.

The results of this study can provide more confidence for critical system designers who are engaged on the proper system performance beyond economic design.

The purpose of this paper is to provide an overview of RAMS engineering in industry and research.

A range of research articles (1988‐2005) covering RAMS engineering is discussed to provide a practical and theoretical overview of RAMS engineering in industry and research.

The paper provides information about the current scenario and also about the past scenario of RAMS engineering in research and industry. Research limitations/implications – This paper reviews much of the literature on RAMS engineering. The literature is collected from major journals and conference proceedings, the period covered is from 1988 to 2005. The authors have tried to make it reasonably comprehensive, but those papers which are not included were either inadvertently overlooked or considered peripheral to this survey. In the present work the authors have only considered those articles which have included two or more aspects of RAMS. Practical implications – The paper is a very useful source of information for researchers working in the area of RAMS engineering. Originality/value – This paper offers help to researchers in understanding the current and past status of RAMS.

This paper considers and discusses analytically the optimal preventive maintenance (PM) policies of aged plants such as fossil‐fired power plants.

Shocks are assumed to occur at a nonhomogeneous Poisson process and the total damage due to each shock is additive. The system undergoes the PM at a certain time or the total damage exceeds a managerial level. The expected cost rate until PM is derived and optimal policies which minimizes it are discussed.

There exists a unique optimal time (T*) or managerial level (k*) which minimizes the expected cost rate. But there does not exist a positive pair (T*, k*), simultaneously.

The damage occurrence distribution is assumed to be nonhomogeneous Poisson one.

Useful methods to consider the optimal PM policies for power plant engineers.

This paper contributes to users of aged power plants economically and practically.

In this paper, a lifetime estimation model for the solder joint is proposed which is capable of considering both severe and running mechanical shocks which is the real case in electric converters in the automotive and aerospace applications. This paper aims to asses the reliability of the solder joint under mixed exposure of mechanical loads.

Mechanical failure process may put at risk the perfect performance of any kinds of electronic systems regardless of the applications they are prepared for. Observation of solder joint health in an electronic assembly under simultaneous exposure of severe and running shocks is an open problem. Three commonly used soldering compositions are considered while the electronic assembly is exposed to three well-known driving cycles.

The results show that the best performance is achieved using SAC405 soldering alloy in comparison with Sn63Pb37 and SAC387 solder alloy. Consideration of mixed exposure to the mechanical loads leads to much more accurate lifetime estimation of the solder joint in the electronic assemblies.

The originality of the paper is confirmed.

The purpose of this paper is to discuss the dynamics of the evolution of damage to the residential buildings within the city walls of Norcia during the six-month seismic swarm that hit Central Italy in the period 24th August 2016 to end of January 2019. This is accomplished by comparing the damage recorded by the Italian Civil Protection usability form (AEDES form) during this period after each event.

First, these outputs are compared with a qualitative assessment conducted by means of omnidirectional camera (ODC) imagery collected on site by the authors, to explore the ability of this technology to support post-earthquake damage assessment. The damage level attributed with these two techniques is then further compared with the output of the analytical vulnerability assessment method FaMIVE, which allows to correlate damage to vulnerability. Specifically, the objective is to investigate the efficacy and performance of historic and recent strengthening interventions.

Results show that there is a good correspondence between AeDES and ODC assessments for low to medium damage grades (DG). Discrepancies in higher DGs are discussed in light of the different levels of information that can be recorded by using the two tools. The efficacy of strengthening is also well captured by the FaMIVE method. The procedure estimates a decrease of almost 40, 25 and 20 per cent of the total number of buildings failing out-of-plane, respectively, for the three seismic events considered, when restraining elements are in action.

The analysis conducted in this work make use of deterministic values of Norcia’s masonry fabric characteristics that have been found in literature, thus implying that neither the probabilistic aspects nor the related uncertainties have been properly investigated and addressed. However, this limitation is to be considered within the more general context of the legislation for the preservation of historic buildings which limits substantially any type of semi-destructive tests, hence limiting the reliability of the values available in literature. This in turn affects the decisions informing the design and implementation of strengthening interventions which can be confidently considered reliable and effective.

The paper addresses for the first time a systematic investigation of damage progression in historic masonry structures, part of urban aggregates in heritage cities. The current urban fabric is discussed in view of historic building codes as the basis for determining the present seismic vulnerability of the historic city centre of Norcia. The study provides new data sets for the city of Norcia and develops a statistical correlation between cumulative damage and analytical vulnerability functions for heritage buildings exposed to a swarm of earthquakes. The analytical assessment of the effect of historic strengthening is totally novel.