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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: 24 August 2021

Vipin Sharma, Abdul Q. Ansari and Rajesh Mishra

The purpose of this paper is to design a efficient layout of Multistage interconnection network which has cost effective solution with high reliability and fault-tolerence…

Abstract

Purpose

The purpose of this paper is to design a efficient layout of Multistage interconnection network which has cost effective solution with high reliability and fault-tolerence capability. For parallel computation, various multistage interconnection networks (MINs) have been discussed hitherto in the literature, however, these networks always required further improvement in reliability and fault-tolerance capability. The fault-tolerance capability of the network can be achieved by increasing the number of disjoint paths as a result the reliability of the interconnection networks is also improved.

Design/methodology/approach

This proposed design is a modification of gamma interconnection network (GIN) and three disjoint path gamma interconnection network (3-DGIN). It has a total seven number of paths for all tag values which is uniform out of these seven paths, three paths are disjoint paths which increase the fault tolerance capability by two faults. Due to the presence of more paths than the GIN and 3-DGIN, this proposed design is more reliable.

Findings

In this study, a new design layout of a MIN has been proposed which provides three disjoint paths and uniformity in terms of an equal number of paths for all source-destination (S-D) pairs. The new layout contains fewer nodes as compared to GIN and 3-DGIN. This design provides a symmetrical structure, low cost, better terminal reliability and provides an equal number of paths for all tag values (|S-D|) when compared with existing MINs of this class.

Originality/value

A new design layout of MINs has been purposed and its two terminal reliability is calculated with the help of the reliability block diagram technique.

Details

International Journal of Pervasive Computing and Communications, vol. 17 no. 4
Type: Research Article
ISSN: 1742-7371

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Article
Publication date: 3 August 2021

Yong-Hua Li, Yang Cao, Yong-Xin Wu, Xiao-Ning Bai and Jia-Wei Mao

This paper aims to establish the relationship between crosswind speed and pantograph-catenary lateral deviation, as well as quantify the influence of crosswind speed and…

Abstract

Purpose

This paper aims to establish the relationship between crosswind speed and pantograph-catenary lateral deviation, as well as quantify the influence of crosswind speed and rod size uncertainty on pantograph-catenary contact reliability.

Design/methodology/approach

The closed vector method is used to establish the pantograph-catenary kinematics formula. A new prediction model is proposed by using the bird swarm algorithm to optimize the grey model. The lateral deviation of the pantograph and catenary is predicted via the new model. Then the relationship between the effective length of the rod and operating mileage is inferred by combining the effective length theory with the Gamma process, as well as the pantograph-catenary contact reliability model is established according to reliability theory.

Findings

The results obtained show the impacts of uncertainty design parameters of pantograph rods on pantograph-catenary contact reliability index, and the results at crosswind speed of 0 ms−1 and 5 ms−1 are 5.0630 and 4.1442, respectively. The reliability decreases with the increasing crosswind speed, and can be greater than the reliability calculated for rod size degradation due to long-term use.

Originality/value

Most preceding works on pantograph-catenary contact reliability were based on principles of dynamics, without considering the pantograph-catenary relative motion. This research reveals the law of pantograph-catenary relative motion for uncertainty design parameters and crosswind, and quantifies the reliability from the angle of kinematics.

Details

International Journal of Structural Integrity, vol. 12 no. 4
Type: Research Article
ISSN: 1757-9864

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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

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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

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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

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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

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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

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Article
Publication date: 1 January 1984

Mohammad Hashim

This article sets out to prove that the basic concepts and techniques of reliability engineering, which are normally applied to material products, can also be applied…

Abstract

This article sets out to prove that the basic concepts and techniques of reliability engineering, which are normally applied to material products, can also be applied effectively to intangible services. It deals in some detail with the power and communication industries and refers also to government.

Details

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

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Article
Publication date: 1 October 1999

Christian N. Madu

The quality performance of a firm is often assessed by the reliability of the firm’s equipment or machinery. Yet, reliability has not received the same attention as…

Abstract

The quality performance of a firm is often assessed by the reliability of the firm’s equipment or machinery. Yet, reliability has not received the same attention as quality. Several organizations today function effectively because the machinery which provides the “system of operation” is highly dependable and reliable. In this paper, we develop a framework that establishes the link between quality, reliability, and maintainability. The aim of this framework is to get corporate attention to focus on reliability issues and also, to establish the link between reliability, company’s bottom line, and corporate survival. A greater focus on “total reliability management (TRM)” will help firms to improve their productivity and efficiency while reducing cost and increasing their competitiveness.

Details

International Journal of Quality & Reliability Management, vol. 16 no. 7
Type: Research Article
ISSN: 0265-671X

Keywords

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