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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

Article
Publication date: 5 October 2022

Raghavendra Rao N. S. and Chitra A.

The purpose of this study is to extend a sensitivity-based reliability technique for the processors deployed in industrial drive (ID).

Abstract

Purpose

The purpose of this study is to extend a sensitivity-based reliability technique for the processors deployed in industrial drive (ID).

Design/methodology/approach

The processor provides flexible operation, re-configurability, and adaptable compatibility in industrial motor drive system. A sensitivity-based model allows a robust tool for validating the system design. Sensitivity is the probability of a partial failure rate for a distributed variable; sensitivity and failure rates are also complementary. Conversely, traditional power electronic components reliability estimating standards have overlooked it, and it is essential to update them to account for the sensitivity parameter. A new sensitivity-based reliability prediction methodology for a typical 32-bit microprocessor operating at 30ºC deployed in ID is presented to fill this gap. The proposed techniques are compared with the estimated processor reliability values obtained from various reliability standards using the validated advanced logistics development tool. The main contribution of this work is to provide a sensitivity extended reliability method over the conventional method directing toward improving reliability, availability, and maintainability in the design of ID.

Findings

The analysis shows that the sensitivity of the processor’s circuit increases due to increases in complexity of the system by reducing the overall mean time between failure upon comparing among conventional reliability standards.

Originality/value

The significance of this paper lies in the overall, sensitivity-based reliability technique for processors in comparison to the traditional reliability complexity in IDs.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 21 September 2022

Sifeng Liu and Wei Tang

The purpose of this paper is to explore new ways and lay a solid foundation to solve the problem of reliability growth analysis of major aerospace equipment with various…

Abstract

Purpose

The purpose of this paper is to explore new ways and lay a solid foundation to solve the problem of reliability growth analysis of major aerospace equipment with various uncertainty data through propose new concepts of general uncertainty data (GUD) and general uncertainty variable (GUV) and build the operation system of GUVs.

Design/methodology/approach

The characteristics of reliability growth data of major aerospace equipment and the limitations of current reliability growth models have been analyzed at first. The most commonly used uncertainty system analysis methods of probability statistics, fuzzy mathematics, grey system theory and rough set theory have been introduced. The concepts of GUD and GUV for reliability growth data analysis of major aerospace equipment are proposed. The simplified form of GUV based on the “kernel” and the degree of uncertainty of GUV is defined. Then an operation system of GUVs is built.

Findings

(1) The concept of GUD; (2) the concept of GUV; (3) The novel operation rules of GUVs with simplified form.

Practical implications

The method exposed in this paper can be used to integrate complex reliability growth data of major aerospace equipment. The reliability growth models based on GUV can be built for reliability growth evaluation and forecasting of major aerospace equipment in practice. The reliability evaluation example of a solid rocket motor shows that the concept and idea proposed in this paper are feasible. The research of this paper opens up a new way for the analysis of complex uncertainty data of reliability growth of major aerospace equipment. Moreover, the operation of GUVs could be extended to the case of algebraic equation, differential equation and matrix which including GUVs.

Originality/value

The new concepts of GUD and GUV are given for the first time. The novel operation rules of GUVs with simplified form were constructed.

Article
Publication date: 15 July 2022

Tulio Coelho, Sofia Diniz, Francisco Rodrigues and Ruben Van Coile

This paper aims to investigate the state of the art for the reliability evaluation of reinforced concrete beams in a fire situation. Special emphasis is placed on…

Abstract

Purpose

This paper aims to investigate the state of the art for the reliability evaluation of reinforced concrete beams in a fire situation. Special emphasis is placed on addressing which parameters were considered probabilistically or deterministically, the prescribed probabilistic models for the assumed stochastic variables, the treatment of the heat transfer mechanism, the quantification of the structural fire performance and the assumed target reliability levels.

Design/methodology/approach

Research papers were identified through a search on the Web of Science, Google Scholar and detailed searches within the journals Journal of Structural Fire Engineering, Fire Technology and Fire Safety Journal, supplemented with references known by the authors.

Findings

Considering the state-of-the-art review, gaps in the literature are identified related to (1) the probabilistic evaluation of shear capacity for standard fires and parametric fires, and bending capacity for parametric fires, (2) the absence of reference fragility curves for immediate design application/code calibration and (3) the specification of target safety levels for reliability-based design.

Originality/value

The lack of research papers gathering studies on the reliability of reinforced concrete beams in fire situation makes it difficult to further develop research in the area. The value of this work lies precisely in the collection of the basic information, making it possible to identify gaps to be addressed in future research and the suggestion of a research framework.

Details

Journal of Structural Fire Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 5 August 2022

Monika Saini, Deepak Sinwar, Alapati Manas Swarith and Ashish Kumar

Reliability and maintainability estimation of any system depends on the identification of the best-fitted probability distribution of failure and repair rates. The…

Abstract

Purpose

Reliability and maintainability estimation of any system depends on the identification of the best-fitted probability distribution of failure and repair rates. The parameters of the best-fitted probability distribution are also contributing significantly to reliability estimation. In this work, a case study of load haul dump (LHD) machines is illustrated that consider the optimization of failure and repair rate parameters using two well established metaheuristic approaches, namely, genetic algorithm (GA) and particle swarm optimization (PSO). This paper aims to analyze the aforementioned points.

Design/methodology/approach

The data on time between failures (TBF) and time to repairs (TTR) are collected for a LHD machine. The descriptive statistical analysis of TBF & TTR data is performed, trend and serial correlation tested and using Anderson–Darling (AD) value best-fitted distributions are identified for repair and failure times of various subsystems. The traditional methods of estimation like maximum likelihood estimation, method of moments, least-square estimation method help only in finding the local solution. Here, for finding the global solution two well-known metaheuristic approaches are applied.

Findings

The reliability of the LHD machine after 60 days on the real data set is 28.55%, using GA on 250 generations is 17.64%, and using PSO on 100 generations and 100 iterations is 30.25%. The PSO technique gives the global best value of reliability.

Practical implications

The present work will be very convenient for reliability engineers, researchers and maintenance managers to understand the failure and repair pattern of LHD machines. The same methodology can be applied in other process industries also.

Originality/value

In this case study, initially likelihood function of the best-fitted distribution is optimized by GA and PSO. Reliability and maintainability of LHD machines evaluated by the traditional approach, GA and PSO are compared. These results will be very helpful for maintenance engineers to plan new maintenance strategies for better functioning of LHD machines.

Details

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

Keywords

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…

1747

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

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…

2079

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

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…

1346

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

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…

892

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

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…

1363

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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