Showing papers in "Reliability Engineering & System Safety in 2002"

TL;DR: A general framework for identifying error and uncertainty in computational simulations that deal with the numerical solution of a set of partial differential equations (PDEs) is developed, applicable to any numerical discretization procedure for solving ODEs or PDEs.

TL;DR: A mathematical model for the maintained system cost is derived and it is confirmed that the maintenance cost rate on an infinite horizon can be minimized by a joint optimization of the maintenance structure thresholds, or equivalently by a Joint optimization of a system replacement threshold and the aperiodic inspection schedule.

TL;DR: A new model, which is useful for modeling this type of failure rate function, is presented and can be seen as a generalization of the Weibull distribution.

TL;DR: A fuzzy-logic-based method for FMEA is presented and a platform for a fuzzy expert assessment is integrated with the proposed system to overcome the potential difficulty in sharing information among experts from various disciplines.

TL;DR: This paper considers a continuously monitored multi-component system and uses a Genetic Algorithm for determining the optimal degradation level beyond which preventive maintenance has to be performed and considers a predictive model describing the evolution of the degrading system based on the use of Monte Carlo simulation.

TL;DR: A recent control scheme based on the cumulative quantity between observations of defects has been proposed which can be easily adopted to monitor the failure process for exponentially distributed inter-failure time and can detect process improvement even in a high-reliability environment.

TL;DR: Mechanized techniques known as ‘model checking’ can be used automatically to discover any scenarios that cause the behaviors of the two descriptions to diverge from one another, and these scenarios identify potential surprises.

TL;DR: The findings suggest that dynamic fault tree is a useful tool to expand and upgrade the existing models and knowledge obtained from probabilistic safety assessment with additional and time dependent information to further reduce the plant risk.

TL;DR: The role of regulatory bodies in fostering strong safety cultures remains unclear, and additional work is required to define the essential attributes of safety culture and to identify reliable performance indicators.

TL;DR: This work model continuously monitored deteriorating systems by using Monte Carlo simulation and embedding the resulting model within an ‘on condition’ maintenance optimisation scheme that aims at minimising the expected total system cost over a given mission time.

TL;DR: The proposed GRP solution accurately describes the failure data, even when a small amount of failure data is available, and application of the classical maximum likelihood and Bayesian approaches to estimation of the GRP parameters are discussed.

TL;DR: In this article, the authors describe the conceptual design and validation of an air traffic management (ATM) concept and the role the safety and human factors played in this design process.

TL;DR: The applications of this approach to dynamic reliability analyses presented in this paper look quite promising and suggest that performing such an approximate epistemic uncertainty analysis is preferable to the alternative of not performing any.

TL;DR: An algorithm to compile mode automata into Boolean equations (fault trees) and the automated generation of fault trees from higher level representations makes easier the maintenance of systems under study.

TL;DR: This paper deals with a stochastic-flow network in which each node and arc has a designated capacity, which will have different lower levels due to various partial and complete failures.

TL;DR: The main idea is to develop an estimation algorithm, by training a model on a restricted data set, and replace system performance evaluation by a simpler calculation, which provides reasonably accurate model outputs.

TL;DR: This paper proposes an analysis strategy aimed at increasing the likelihood of obtaining a BDD for any given fault tree, by ensuring the associated calculations are as efficient as possible.

TL;DR: The application to ordering of random variables via the proportional reversed hazard rate model is considered, and the connection with the mean waiting time is studied.

TL;DR: This paper aims at minimizing the cost per unit of time for an infinite time span by selection of a unique interval, for both inspection and maintenance, for single unit system that alternates operating and idle periods.

TL;DR: This paper studies the condition-based maintenance, and derives closed-form expressions of system availability when the device undergoes both deterioration as well as Poisson type failures, to find faster algorithms to determine the optimal inspection policy.

TL;DR: New forms of fuzzy membership curves are introduced, designed to consider the uncertainty range that represents the degree of uncertainties involved in both probabilistic parameter estimates and subjective judgments.

TL;DR: An approach to ATM incident analysis that is being developed in the European ATM arena is dealt with, which aims to determine how and why human errors are contributing to incidents, and thus how to improve human reliability within a high-reliability system.

TL;DR: The author suggests that, because of the differences in the analysis techniques, one analysis technique is to be preferred and the Enhanced Markov Analysis technique could be used for this purpose because it covers most aspects relevant for quantification of safety.

TL;DR: This paper shows how approximate failure rates for components can be used to select the most likely combinations of failures for automated investigation using simulation, making it practical for engineers to study and act on the results.

TL;DR: Results of several examples showed that it is possible to reduce risk by application of the proposed optimization method and increases the importance of evaluation speed versus the requirement of getting always the global optimum no matter if it is only slightly better that certain local one.

TL;DR: The trade-off between flexibility and complexity of semi-Markovian probabilistic models is explored, and a comparison in terms of model data requirements versus potential benefits obtained with the model is presented.

TL;DR: Reliability centred maintenance methodology offers the best available strategy for PM optimisation and features of predictive maintenance of a medium scale steel industry are deduced through this paper in a rather generalised form.

TL;DR: This paper represents a methodology that can be used for identifying the failure sequences and assessing the probability of their occurrence in a manufacturing system and employs Petri net modeling and reachability trees constructed based on the Petri nets.

TL;DR: The proposed model is meaningful in capturing the physical phenomena occurring during the system lifetime and provides for simpler and more effective parameter fitting than the usually adopted ‘bathtub’ procedures.

TL;DR: A formulation to compute the reliability of reinforced concrete structures, in which physical and geometrical non-linearities are taken into account, is described.