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Article
Publication date: 12 November 2010

Wei Liu, Yongshou Liu and Zhufeng Yue

Pressure pulsations and vibration working condition lead to dynamic troubles in hydraulic devices. It is highly desirable to be able to estimate the durability at the…

Abstract

Purpose

Pressure pulsations and vibration working condition lead to dynamic troubles in hydraulic devices. It is highly desirable to be able to estimate the durability at the design stage so that appropriate maintenance period can be determined for safety and reliability. The purpose of this paper is to propose a quantitative evaluation method for pulsation and vibration based on reliability.

Design/methodology/approach

Pressure pulsations are approximately treaded as a stationary random process. The principle of transform function and fluid network chain rules are used to disassemble the hydraulic power unit into the series‐system. Mean square deviation of dynamic stress under the pumping source white noise exciting was calculated based on frequency responses. Statistical regularity of displacement and stress responses of pipelines under external random vibration are obtained by the spectrum analysis. Both the first‐passage failure criterion and fatigue damage accumulation failure criterion are adopted to analyze the dynamic pressure reliability of hydraulic pipelines.

Findings

The terminal joint, bellow pipe and pipe clamps are verified as the weak location of the pipelines. The mean square deviations of pulsations and vibration response influence the pipelines reliability. The results indicated that the preventative design method of controlling the pressure below 10 per cent of rated pressure does not meet the security specification of the hydraulic power unit.

Originality/value

The paper proposes a quantitative evaluation method for random pressure pulsation and external vibration based on reliability, which provides a new approach for the safety assessment and design of hydraulic pipelines.

Details

Multidiscipline Modeling in Materials and Structures, vol. 6 no. 4
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 20 August 2019

Xiaoxiao Liu and Ming Liu

Corrosion is one of the common damage mechanisms in many engineering structures such as marine structures, petroleum pipelines, aerospace and nuclear reactor. However, the…

Abstract

Purpose

Corrosion is one of the common damage mechanisms in many engineering structures such as marine structures, petroleum pipelines, aerospace and nuclear reactor. However, the service performance of metal materials and structures is gradually degenerating with the increase of service life due to the rapid growth of corrosion damages. Thus, the coupled effects for corrosion damage in reliability analysis should be considered urgently. Then, the purpose of this paper is to develop the corrosion damage physical model and the corresponding reliability analysis methods, which consider the coupled effect of corrosion damage.

Design/methodology/approach

A failure physical model, considering the coupled effect of pitting growth, crack and crack propagation, is presented in this paper. Sequentially, the corrosion reliability with respect to pitting physical damage can be investigated. The presented pitting damage physical model is formulated as time-variant performance limit state functions, which include the crack transition, crack growth and fracture failure mechanics. The first-passage failure criterion is used to construct the corrosion reliability framework, involving in the pitting damage model with the increase of service life.

Findings

Results demonstrate that the multiplicative dimensional reduction (MDR) method behaves much better than FORM no matter in accuracy or efficiency. The proposed corrosion reliability method is applicable for dealing with the damage failure model of the structural pitting corrosion.

Originality/value

The MDR method is used to calculate the corrosion reliability index of a given structure with fewer function calls. Finally, an aeronautical metal material is used to demonstrate the efficiency and precision of the proposed corrosion reliability method when the failure physical model considering the coupled effects of mechanical stresses and corrosion environment is adopted.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 5
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 31 August 2020

Bingqian Chen, Anqiang Wang, Qing Guo, Jiayin Dai and Yongshou Liu

This paper aims to solve the problem that pipes conveying fluid are faced with severe reliability failures under the complicated working environment.

Abstract

Purpose

This paper aims to solve the problem that pipes conveying fluid are faced with severe reliability failures under the complicated working environment.

Design/methodology/approach

This paper proposes a dynamic reliability and variance-based global sensitivity analysis (GSA) strategy with non-probabilistic convex model for pipes conveying fluid based on the first passage principle failure mechanism. To illustrate the influence of input uncertainty on output uncertainty of non-probability, the main index and the total index of variance-based GSA analysis are used. Furthermore, considering the efficiency of traditional simulation method, an active learning Kriging surrogate model is introduced to estimate the dynamic reliability and GSA indices of the structure system under random vibration.

Findings

The variance-based GSA analysis can measure the effect of input variables of convex model on the dynamic reliability, which provides useful reference and guidance for the design and optimization of pipes conveying fluid. For designers, the rankings and values of main and total indices have essential guiding role in engineering practice.

Originality/value

The effectiveness of the proposed method to calculate the dynamic reliability and sensitivity of pipes conveying fluid while ensuring the calculation accuracy and efficiency in the meantime.

Details

Engineering Computations, vol. 38 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 19 August 2021

Sheng Peng, Lu-jun Cai, Tian-hua Jiang and Xu Kai

The purpose of this paper is to investigate the explosive performance and explosion damage mechanism of T-beam bridge structure.

Abstract

Purpose

The purpose of this paper is to investigate the explosive performance and explosion damage mechanism of T-beam bridge structure.

Design/methodology/approach

On the basis of the existing specification, two T-beam bridge models were designed and fabricated. Test specimens of different explosive dosage and different blast height were carried out. The mechanical process, failure mode, blast damage model, damage identification mechanism and blast evolution law and quantitative evaluation were taken into account.

Findings

The results revealed that the web plate fracture failure is the key to the unstable failure of the whole T-beam bridge. The explosion failure phenomenon and blast damage evaluation criterion of RC T-beam bridge was divided into five stages: the original cracks stage of concrete material (D = 0 ∼ 0.1), the fractures initiation stage of concrete material (D = 0.1 ∼ 0.3), the stable expansion stage of cracks in concrete material (D = 0.3 ∼ 0.55), the unstable expansion stage of cracks in concrete material (D = 0.55 ∼ 0.8), the explosion fracture of steel bars and the overall instability and damage of the bridge (D = 0.8 ∼ 1.0), which can also be described as basically intact, slight damage, moderate damage, severe damage and collapsed.

Social implications

The research result will provide basis for the antiknock evaluation and damage repair technical specifications of the RC T-beam bridge.

Originality/value

The research results of damage evaluation serve as a basis for damage repair and reinforcement of bridge structures after explosion.

Details

Sensor Review, vol. 41 no. 4
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 1 February 1985

D.M. Barry

This article describes reliability analysis and failure cause determination in encapsulated semiconductor devices. Such devices were subjected to a destructive life test…

Abstract

This article describes reliability analysis and failure cause determination in encapsulated semiconductor devices. Such devices were subjected to a destructive life test using temperature as an accelerating stress. Once the devices had failed, the failure data were statistically analysed with the aid of a digital computer. The failed devices were then decapsulated and failure causes were determined using different types of microscopy. The article gives detailed information about the tests and analysis mentioned above.

Details

International Journal of Quality & Reliability Management, vol. 2 no. 2
Type: Research Article
ISSN: 0265-671X

Article
Publication date: 1 January 1975

Knight's Industrial Law Reports goes into a new style and format as Managerial Law This issue of KILR is restyled Managerial Law and it now appears on a continuous…

Abstract

Knight's Industrial Law Reports goes into a new style and format as Managerial Law This issue of KILR is restyled Managerial Law and it now appears on a continuous updating basis rather than as a monthly routine affair.

Details

Managerial Law, vol. 18 no. 1
Type: Research Article
ISSN: 0309-0558

Article
Publication date: 13 February 2019

Preeti Wanti Srivastava and Manisha Manisha

Zero-failure reliability testing aims at demonstrating whether the product has achieved the desired reliability target with zero failure and high confidence level at a…

Abstract

Purpose

Zero-failure reliability testing aims at demonstrating whether the product has achieved the desired reliability target with zero failure and high confidence level at a given time. Incorporating accelerated degradation testing in zero-failure reliability demonstration test (RDT) facilitates early failure in high reliability items developed within short period of time to be able to survive in fiercely competitive market. The paper aims to discuss these issues.

Design/methodology/approach

The triangular cyclic stress uses one test chamber thus saving experimental cost. The parameters in model are estimated using maximum likelihood methods. The optimum plan consists in finding out optimum number of cycles, optimum specimens, optimum stress change point(s) and optimum stress rates.

Findings

The optimum plan consists in finding out optimum number of cycles, optimum specimens, optimum stress change point(s) and optimum stress rates by minimizing asymptotic variance of estimate of quantile of the lifetime distribution at use condition subject to the constraint that total testing or experimental cost does not exceed a pre-specified budget. Confidence intervals of the design parameters have been obtained and sensitivity analysis carried out. The results of sensitivity analysis show that the plan is robust to small deviations from the true values of baseline parameters.

Originality/value

For some highly reliable products, even accelerated life testing yields little failure data of units in a feasible amount of time. In such cases accelerated degradation testing is carried out, wherein the failure termed as soft failure is defined in terms of performance characteristic of the product exceeding its critical (threshold) value.

Details

International Journal of Quality & Reliability Management, vol. 36 no. 3
Type: Research Article
ISSN: 0265-671X

Keywords

Article
Publication date: 11 January 2022

Wei Yang, Afshin Firouzi and Chun-Qing Li

The purpose of this paper is to demonstrate the applicability of the Credit Default Swaps (CDS), as a financial instrument, for transferring of risk in project finance…

Abstract

Purpose

The purpose of this paper is to demonstrate the applicability of the Credit Default Swaps (CDS), as a financial instrument, for transferring of risk in project finance loans. Also, an equation has been derived for pricing of CDS spreads.

Design/methodology/approach

The debt service cover ratio (DSCR) is modeled as a Brownian Motion (BM) with a power-law model fitted to the mean and half-variance of the existing data set of DSCRs. The survival probability of DSCR is calculated during the operational phase of the project finance deal, using a closed-form analytical method, and the results are verified by Monte Carlo simulation (MCS).

Findings

It is found that using the power-law model yields higher CDS premiums. This in turn confirms the necessity of conducting rigorous statistical analysis in fitting the best performing model as uninformed reliance on constant time-invariant drift and diffusion model can erroneously result in smaller CDS spreads. A sensitivity analysis also shows that the results are very sensitive to the recovery rate and cost of debt values.

Originality/value

Insufficiency of free cash flow is a major risk in the toll road project finance and hence there is a need to develop innovative financial instruments for risk management. In this paper, a novel valuation method of CDS is proposed assuming that DSCR follows the BM stochastic process.

Details

Journal of Financial Management of Property and Construction , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1366-4387

Keywords

Article
Publication date: 8 February 2016

Ting-Jui Chou, En-Chung Chang, Yanan Zheng and Xiaofei Tang

The purpose of this study is to explore the effects of priming on consumer emotions and willingness to pay as consumers experience two services with two opposite valences.

2163

Abstract

Purpose

The purpose of this study is to explore the effects of priming on consumer emotions and willingness to pay as consumers experience two services with two opposite valences.

Design/methodology/approach

A 2 (service experience sequence: failure–success, success–failure) × 3(priming: positive, negative, no priming) between-subject experiment was conducted with 230 college students in China.

Findings

Results indicate that when priming information is included, people give greater decision weight to the second service. Specifically, in the failure–success scenario, priming information between two services increases positive emotions and decreases negative emotions, raising willingness to pay. In the success–failure scenario, priming information decreases positive emotions and increases negative emotions, thus lowering willingness to pay.

Practical implications

First, if businesses discover the possibility of a service failure, then disclosing negative information is better than whitewashing the truth. Second, services following a campaign of positively framed messages should be carefully rendered. The damage of pre-failure positive priming is most certainly irreparable. Finally, in terms of communication, businesses and service providers should cater to consumers exposed to different levels of information accordingly.

Originality/value

Previous investigations focusing on a single purchase have argued that priming effects should cause consumers of varying tastes to react in a more unified manner to a service. This study extends the research scope to more realistic situations ”sequential service experiences with opposite valences” and asserts that differences in service experiences alter the influence of priming information.

Details

Journal of Services Marketing, vol. 30 no. 1
Type: Research Article
ISSN: 0887-6045

Keywords

Book part
Publication date: 2 October 2019

Suzanne Ross

In this chapter Suzanne Ross draws on her experience previously as a talent manager and now as a leadership consultant, Executive Coach and Senior Lecturer in Executive…

Abstract

In this chapter Suzanne Ross draws on her experience previously as a talent manager and now as a leadership consultant, Executive Coach and Senior Lecturer in Executive Education, and applies her research on leadership derailment to talent management. As organizations continue to invest in leadership development, research suggests up to 50 per cent of leaders derail or fail in their role. The derailment literature is, to-date, disconnected from TM although central to the definition of leadership derailment is that derailed leaders were previously successful and had potential. The chapter explores the concept of derailment, how it is defined, its scale and scope and some of the causes of derailment including a lack of organizational support during leadership transitions. The notion of the ‘accidental manager’ is used to provide an example of where literature on TM and derailment converge as a key derailer characteristic is having an overly functional orientation. This maps to the accidental manager concept and to the challenges that TM practitioners face in developing career pathways for expert/specialists beyond managerial roles. Suzanne argues that talent identification should take more account of derailment characteristics and suggests there may be gender differences in how these are perceived and in the consequences that arise when they are present. The chapter contributes to a greater understanding of how the concept of derailment can be integrated within talent management research and practice.

Details

Managing Talent: A Critical Appreciation
Type: Book
ISBN: 978-1-83909-094-3

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