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Book part
Publication date: 8 May 2003

Hiroshi Inouye

In this paper, a model to estimate travel time reliability is proposed assuming a stochastic user equilibrium. Travel time reliability is defined as the probability that…

Abstract

In this paper, a model to estimate travel time reliability is proposed assuming a stochastic user equilibrium. Travel time reliability is defined as the probability that travel time between the origin and destination does not exceed a standard travel time corresponding to each service level. Also it is shown how to calculate travel time reliability in a large-scale network. This model is applied to the road network in the Hanshin area to evaluate new lines in the national road plan from the viewpoint of travel time reliability. Some important links and lines in the future road network are evaluated from the viewpoint of travel time reliability.

Details

The Network Reliability of Transport
Type: Book
ISBN: 978-0-08-044109-2

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Article
Publication date: 3 June 2021

Shuai Li, Zhencai Zhu, Hao Lu and Gang Shen

This paper aims to present a dynamic reliability model of scraper chains based on the fretting wear process and propose a reasonable structural optimization method.

Abstract

Purpose

This paper aims to present a dynamic reliability model of scraper chains based on the fretting wear process and propose a reasonable structural optimization method.

Design/methodology/approach

First, the dynamic tension of the scraper chain is modeled by considering the polygon effect of the scraper conveyor. Then, the numerical wear model of the scraper chain is established based on the tangential and radial fretting wear modes. The scraper chain wear process is introduced based on the diameter wear rate. Furthermore, the time-dependent reliability of scraper chains based on the fretting wear process is addressed by the third-moment saddlepoint approximation (TMSA) method. Finally, the scraper chain is optimized based on the reliability optimization design theory.

Findings

There is a correlation between the wear and the dynamic tension of the scraper conveyor. The unit sliding distance of fretting wear is affected by the dynamic tension of the scraper conveyor. The reliability estimation of the scraper chain with incomplete probability information is achieved by using the TMSA for the method needs only the first three statistical moments of the state variable. From the perspective of the chain drive system, the reliability-based optimal design of the scraper chain can effectively extend its service life and reduce its linear density.

Originality/value

The innovation of the work is that the physical model of the scraper chain wear is established based on the dynamic analysis of the scraper conveyor. And based on the physical model of wear, the time-dependent reliability and optimal design of scraper chains are carried out.

Details

Engineering Computations, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0264-4401

Keywords

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Article
Publication date: 14 May 2021

Ahmad Ghaith, Huimin Ma and Ashraf W. Labib

High-reliability performance and high-hazard are intertwined in High-Reliability Organizations (HROs) operations; these organizations are highly safe, highly hazardous and…

Abstract

Purpose

High-reliability performance and high-hazard are intertwined in High-Reliability Organizations (HROs) operations; these organizations are highly safe, highly hazardous and highly significant for the modern society, not only for the valuable resources they have, but also the indispensable services they provide. This research intend to understand how HROs could produce high quality performance despite their challenging and demanding contexts. The research followed an emic approach to develop an organizational framework that reflects the contribution of the seeming traits of the organizations to the operations safety based on the workers point of views about the safety of workstations.

Design/methodology/approach

This research adopted mixed methods of in-depth interviews and literature review to identify the structural characteristics of high-reliability organizations (HROs) embedded in the organizations studies and developed a theoretical based structural framework for HROs. Furthermore, a systemic literature review was adopted to find the evidence from the organizations literature for the identified characteristics from the interviews from the first stage. The setting for this study is six Chinese power stations, four stations in Hubei province central China and two stations in the southern China Guangdong province.

Findings

The organizational framework is a key determinant to achieve high-reliability performance; however, solely it cannot explain how HROs manage the risks of hazard events and operate safely in high-hazard environments. High-reliability performance is attributed to the interaction between two sets of determinants of safety and hazard. The findings of this research indicate that HROs systems would be described as reliable or hazardous depending on the tightly coupled setting, complexity, bureaucracy involvement and dynamicity within the systems from one hand, and safety orientation, failure intolerance, systemwide processing, the institutional setting and the employment of redundant systems on other hand.

Originality/value

The authors developed an organizational framework of organizing the safety work in HROs. The applied method of interviewing and literature review was not adopted in any other researches.

Details

International Journal of Quality & Reliability Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0265-671X

Keywords

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Article
Publication date: 17 May 2021

Xian Zhang, Gedong Jiang, Hao Zhang, Xialun Yun and Xuesong Mei

The purpose of this paper is to analyze the dependent competing failure reliability of harmonic drive (HD) with strength failure and degradation failure.

Abstract

Purpose

The purpose of this paper is to analyze the dependent competing failure reliability of harmonic drive (HD) with strength failure and degradation failure.

Design/methodology/approach

Based on life tests and stiffness degradation experiments, Wiener process is used to establish the accelerated performance degradation model of HD. Model parameter distribution is estimated by Bayesian inference and Markov Chain Monte Carlo (MCMC) and stiffness degradation failure samples are obtained by a three-step sampling method. Combined with strength failure samples of HD, copula function is used to describe the dependence between strength failure and stiffness degradation failure.

Findings

Strength failure occurred earlier than degradation failure under high level accelerated condition; degradation failure occurred earlier than strength failure under medium- or low-level accelerated condition. Gumbel copula is the optimum copula function for dependence modeling of strength failure and stiffness degradation failure. Dependent competing failure reliability of HD is larger than independent competing failure reliability.

Originality/value

The reliability evaluation method of dependent competing failure of HD with strength failure and degradation failure is first proposed. Performance degradation experiments during accelerated life test (ALT), step-down ALT and life test under rated condition are conducted for Wiener process based step-down accelerated performance degradation modeling.

Details

Engineering Computations, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0264-4401

Keywords

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Article
Publication date: 29 April 2021

Suyuan Wang, Huaming Song and Canran Gong

Companies face the critical reliability problem of products due to the development of outsourcing. This study intends to provide some feasible solutions for a company to…

Abstract

Purpose

Companies face the critical reliability problem of products due to the development of outsourcing. This study intends to provide some feasible solutions for a company to improve the reliability level of products.

Design/methodology/approach

The paper considers the reward and reliability decisions regarding a product made with two complementary components from two different suppliers: high-capable and low-capable. Two kinds of reliability improvement incentives (normal incentive and cost-sharing incentive) through which a manufacturer provides a reward and shares the reliability improvement cost with a supplier are discussed. As the Stackelberg leader, the manufacturer determines the strategy, while the suppliers are responsible for determining its reliability. Using a game-theoretic framework, four different contract scenarios are addressed. We develop analytical methods to better understand how the manufacturer decides the incentive mechanism to be used for the suppliers.

Findings

The results show that cost-sharing contracts do not always lead to a higher reliability level and more enormous profits. Setting a target reliability level is better for the manufacturer. The cost-sharing contract is beneficial for a high-capable supplier even though it does not directly participate in that kind of mechanism. A low-capable supplier gains more profit when the manufacturer provides incentive mechanisms that do not specify a target reliability level.

Originality/value

This paper investigates the reliability improvement mechanism used for complementary products and focuses on identifying the optimal decisions when demand is influenced by the gap between the product's failure rate and the standard failure rate.

Details

The TQM Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1754-2731

Keywords

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Article
Publication date: 20 June 2008

B. Sharma and O.P. Gandhi

The lubricating oil is a non‐renewable source of energy and its useful life is limited due to deterioration during its usage. It is desirable to maximize its use to…

Abstract

Purpose

The lubricating oil is a non‐renewable source of energy and its useful life is limited due to deterioration during its usage. It is desirable to maximize its use to conserve this scarce resource. At present, continuation or change of the engine oil is decided, based on the manufacturer's recommendation and experience. The suggested engine oil change period is conservative and results in non‐efficient usage of engine oil. This practice needs refinement to include all possible properties/attributes of engine oil and use of appropriate procedure to assess its realistic performance. The paper aims to analyze the procedure.

Design/methodology/approach

Oil reliability polygraph is used to analyze the engine oil performance during operation. Reliability analysis of the engine oil is carried out by comparing the area of oil reliability polygraph at a given operation time with the area for the fresh engine oil. The suggested procedure is illustrated by means of an example.

Findings

Physical and chemical properties responsible for performance degradation of the engine oil are considered as engine oil reliability attributes. The value of these attributes from time to time, obtained by analyzing samples drawn from the system, is analyzed through oil reliability polygraph. In this approach, the engine oil reliability attributes at a given operation time are represented in terms of reliability value to obtain the “oil reliability polygraph”.

Originality/value

The suggested procedure will be helpful for maintenance personnel in taking planned maintenance action.

Details

Industrial Lubrication and Tribology, vol. 60 no. 4
Type: Research Article
ISSN: 0036-8792

Keywords

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Article
Publication date: 30 March 2010

Shaomin Wu, Keith Neale, Michael Williamson and Matthew Hornby

The purpose of this study is to highlight special characteristics of building services systems and investigate how practitioners view reliability and maintenance. These…

Abstract

Purpose

The purpose of this study is to highlight special characteristics of building services systems and investigate how practitioners view reliability and maintenance. These characteristics include energy‐hungry services systems, operating modes, maintenance types, the relationship between procurement costs and maintenance costs.

Design/methodology/approach

The practitioners' viewpoints on reliability and maintenance are explored through a workshop. The authors wish to draw the attention of researchers in the reliability and maintenance community and furthermore emphasise the difference between building services systems and systems in industries other than construction.

Findings

It is shown that a lack of failure data and maintenance data is the main problem from both academic researchers' and industrial practitioner's points of view. The paper suggests that there exists no fixed cost ratio available to apply to building services systems; the analysis of RAMS (Reliability, Availability, Maintainability and Safety) should include duty cycles and the environment; and clients of the construction industry would benefit from mandating a LCC to be applied to the build.

Practical implications

The gap between academia and practitioners should be bridged through better understanding each other's needs. Accurately estimating the ratio between procurement and maintenance costs is needed from a whole life costing perspective.

Originality/value

This paper is a good reference for building designers, facility managers and maintenance staff of building services systems. It also offers reliability researchers references on special characteristics of building services systems.

Details

Journal of Quality in Maintenance Engineering, vol. 16 no. 1
Type: Research Article
ISSN: 1355-2511

Keywords

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Article
Publication date: 1 April 1997

Huei‐Yaw Ke and Ching‐Piao Hwang

Shows that the new ISO 9000‐4 has covered the dependability aspects of IEC 300‐1. Dependability is defined as a collective term used to describe availability performance…

Abstract

Shows that the new ISO 9000‐4 has covered the dependability aspects of IEC 300‐1. Dependability is defined as a collective term used to describe availability performance and its influencing factors, such as reliability performance, maintainability performance and maintenance support performance. Among these factors, reliability is the major quality assessment of a product during the operation period. With reliability as a necessary requirement, the quality assurance activities taken by suppliers should be extended, especially to cover the survey of the environmental condition, and maintenance planning for the purposes of reliability assurance. Summarizes the characteristics of reliability assurance in the ISO 9000‐4 aspect and, by applying the system engineering concept, proposes a systematic approach for a reliability management programme based on ISO 9000‐4. Believes that, after tailoring in practices, the merits of this approach will be evident in project management.

Details

International Journal of Quality & Reliability Management, vol. 14 no. 3
Type: Research Article
ISSN: 0265-671X

Keywords

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Article
Publication date: 12 January 2010

R. Chinnaiyan and S. Somasundaram

The purpose of this paper is to evaluate the reliability of individual software components in terms of the probability that each software component performs its intended…

Abstract

Purpose

The purpose of this paper is to evaluate the reliability of individual software components in terms of the probability that each software component performs its intended functionality successfully. The overall software system reliability is evaluated.

Design/methodology/approach

This paper incorporates the reliability behavior of component‐based software system using Markov process.

Findings

It is found that the component‐based software system reliability increases as the component reliability increases.

Originality/value

This paper explores new directions in evaluating the reliability of component‐based software systems for software reliability and offers practical help to researchers and software industries in reliable software development. The proposed software simulation technique will act as a tool for the software quality assurance team for evaluating the reliability of component‐based software systems.

Details

International Journal of Quality & Reliability Management, vol. 27 no. 1
Type: Research Article
ISSN: 0265-671X

Keywords

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Article
Publication date: 1 July 1996

James Prendergast, Eammon Murphy and Malcom Stephenson

Argues that in the coming years the present methods of demonstrating reliability will no longer be feasible and alternative methods must be found. Deals with building‐in…

Abstract

Argues that in the coming years the present methods of demonstrating reliability will no longer be feasible and alternative methods must be found. Deals with building‐in reliability (BIR) and the necessity to change from the standard end‐of‐line‐measurement technique of life test to a more proactive in‐line approach, where reliability can be measured by process parameters and reaction time is immediate, resulting in a continuous flow of reliable product to the end user. This approach will not eliminate the use of end‐of‐line monitoring, but will reduce the amount which needs to be carried out. Suggests that it will only be done to demonstrate that processes are operating to certain maximum failure rates, where the online controls will in fact guarantee that the reliability is much greater than that being demonstrated. Examines the customers’ attitude towards reliability, and points out that sharing of data will be essential if the BIR approach is to be successful. Outllines two examples which demonstrate the effectiveness of a BIR program and explains how, if implemented, it can be used to prevent the manufacture of potentially unreliable product.

Details

International Journal of Quality & Reliability Management, vol. 13 no. 5
Type: Research Article
ISSN: 0265-671X

Keywords

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