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Article
Publication date: 13 May 2021

Aiping Jiang, Zhenni Huang, Jiahui Xu and Xuemin Xu

The purpose of this paper is to propose a condition-based opportunistic maintenance policy considering economic dependence for a series–parallel hybrid system with a K-out-of-N

209

Abstract

Purpose

The purpose of this paper is to propose a condition-based opportunistic maintenance policy considering economic dependence for a series–parallel hybrid system with a K-out-of-N redundant structure, where a single component in series is denoted as subsystem1, and K-out-of-N redundant structure is denoted as subsystem2.

Design/methodology/approach

Based on the theory of Residual Useful Life (RUL), inspection points are determined, and then different maintenance actions are adopted in the purpose of minimizing the cost rate. Both perfect and imperfect maintenance actions are carried out for subsystem1. More significantly, regarding economic dependence, condition-based opportunistic maintenance is designed for the series–parallel hybrid system: preemptive maintenance for subsystem1, and both preemptive and postponed maintenance for subsystem2.

Findings

The sensitivity analysis indicates that the proposed policy outperforms two classical maintenance policies, incurring the lowest total cost rate under the context of both heterogeneous and quasi-homogeneous K-out-of-N subsystems.

Practical implications

This model can be applied in series–parallel systems with redundant structures that are widely used in power transmission systems in electric power plants, manufacturing systems in textile factories and sewerage systems. Considering inconvenience and high cost incurred in the inspection of hybrid systems, this model helps production managers better maintain these systems.

Originality/value

In maintenance literature, much attention has been received in repairing strategies on hybrid systems with economic dependence considering preemptive maintenance. Limited work has considered postponed maintenance. However, this paper uses both condition-based preemptive and postponed maintenance on the issue of economic dependence bringing opportunities for grouping maintenance activities for a series–parallel hybrid system.

Details

Journal of Quality in Maintenance Engineering, vol. 28 no. 3
Type: Research Article
ISSN: 1355-2511

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Article
Publication date: 14 November 2019

Aiping Jiang, Qingxia Li, Jinyi Yan, Leqing Huang and Haining Wu

The purpose of this paper is to focus on finding the optimal maintenance interval and the minimum maintenance cost for redundant system, considering environment factors.

226

Abstract

Purpose

The purpose of this paper is to focus on finding the optimal maintenance interval and the minimum maintenance cost for redundant system, considering environment factors.

Design/methodology/approach

The authors propose a decision model with environment-based preventive maintenance for the repairable redundant system. Referring to the k-out-of-n model and Proportional Hazard Model, the reliability analysis is completed for the redundant system affected by internal and external issues. Meanwhile, the maintenance cost for the redundant system is divided into two categories: the fixed maintenance cost involving whole system replacement at the time of system failure, and the cost to replace failure components when the system still functions.

Findings

Upon the required reliability analysis, an optimal maintenance interval that minimizes the average maintenance cost per unit time is identified. The simulation results indicate that the optimal maintenance interval with consideration of environmental factors is significantly shorter than that without consideration of these factors, with the maintenance cost increase within 10 percent.

Practical implications

The redundant systems have widely been used in industries including the aero craft control system and warship power system. The model could be applied in the more real case considering the types of components and the operation environment, and help production managers better maintain machines by increasing the safety and reliability of the redundant model with the more frequent inspection.

Originality/value

Previous research of redundant system always focuses on internal degradation, while ignoring the reliability analysis for a redundant system with various multiple components under the influence of environment. However, this work could fill the theoretical gap, i.e. simultaneously consider both environmental and internal factors for a redundant system with non-homogeneous components. Meanwhile, the proposed superior model increases the reliability and safety of the k-out-of-n model with reasonable cost. Production managers could benefit a lot from this as well.

Details

Journal of Quality in Maintenance Engineering, vol. 26 no. 4
Type: Research Article
ISSN: 1355-2511

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Article
Publication date: 24 August 2022

Ronghua Cai, Jiamei Yang, Xuemin Xu and Aiping Jiang

The purpose of this paper is to propose an improved multi-objective optimization model for the condition-based maintenance (CBM) of single-component systems which considers…

142

Abstract

Purpose

The purpose of this paper is to propose an improved multi-objective optimization model for the condition-based maintenance (CBM) of single-component systems which considers periodic imperfect maintenance and ecological factors.

Design/methodology/approach

Based on the application of non-periodic preventive CBM, two recursion models are built for the system: hazard rate and the environmental degradation factor. This paper also established an optimal multi-objective model with a normalization process. The multiple-attribute value theory is used to obtain the optimal preventive maintenance (PM) interval. The simulation and sensitivity analyses are applied to obtain further rules.

Findings

An increase in the number of the occurrences could shorten the duration of a maintenance cycle. The maintenance techniques and maintenance efficiency could be improved by increasing system availability, reducing cost rate and improving degraded condition.

Practical implications

In reality, a variety of environmental situations may occur subsequent to the operations of an advanced manufacturing system. This model could be applied in real cases to help the manufacturers better discover the optimal maintenance cycle with minimized cost and degraded condition of the environment, helping the corporations better fulfill their CSR as well.

Originality/value

Previous research on single-component condition-based predictive maintenance usually focused on the maintenance costs and availability of a system, while ignoring the possible pollution from system operations. This paper proposed a modified multi-objective optimization model considering environment influence which could more comprehensively analyze the factors affecting PM interval.

Details

Journal of Quality in Maintenance Engineering, vol. 29 no. 2
Type: Research Article
ISSN: 1355-2511

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Book part
Publication date: 9 December 2024

Bhupinder Singh, Christian Kaunert, Komal Vig and Ritu Gautam

The retail industry is undergoing a transformative shift with the integration of augmented reality (AR) and virtual reality (VR) technologies. The contemporary retail landscape is…

Abstract

The retail industry is undergoing a transformative shift with the integration of augmented reality (AR) and virtual reality (VR) technologies. The contemporary retail landscape is witnessing a paradigm shift propelled by the assimilation of AR and VR technologies. The merging of AR and VR technology is bringing about an intense transition in the retail business, which is a constantly changing terrain. The retail industry is entering a new era of immersive and personalized shopping experiences because to this dynamic combination, which is changing the way consumers interact with items and places. With AR apps, customers can aim their smartphones to easily find things, get promotions in real time, and learn more about them. A virtual try-on experience that lets buyers see things in a virtual setting is made possible by AR. With realistic AR simulations, clients can try on items and arrange furnishings in their living room, making better educated purchases. The retailers are now able to provide much customized product suggestions because to AR. AR apps may make personalized product recommendations based on consumer preferences and purchase history, improving the entire shopping experience and raising customer happiness. This paper explores the many uses, difficulties and potential consequences of AR and VR in retail, emphasizing the significant transformations these technologies bring about for the sector. In-store navigation is being revolutionized by AR, which offers consumers an engaging and user-friendly navigational experience.

Details

Augmenting Retail Reality, Part B: Blockchain, AR, VR, and AI
Type: Book
ISBN: 978-1-83608-708-3

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Article
Publication date: 3 August 2020

Omar Ahmed, Golareh Jalilvand, Scott Pollard, Chukwudi Okoro and Tengfei Jiang

Glass is a promising interposer substrate for 2.5 D integration; yet detailed analysis of the interfacial reliability of through-glass vias (TGVs) has been lacking. The purpose of…

415

Abstract

Purpose

Glass is a promising interposer substrate for 2.5 D integration; yet detailed analysis of the interfacial reliability of through-glass vias (TGVs) has been lacking. The purpose of this paper is to investigate the design and material factors responsible for the interfacial delamination in TGVs and identify methods to improve reliability.

Design/methodology/approach

The interfacial reliability of TGVs is studied both analytically and numerically. An analytical solution is presented to show the dependence of the energy release rate (ERR) for interfacial delamination on the via design and the thermal mismatch strain. Then, finite element analysis (FEA) is used to investigate the influence of detailed design and material factors, including the pitch distance, via aspect ratio, via geometry and the glass and via materials, on the susceptibility to interfacial delamination.

Findings

ERR for interfacial delamination is directly proportional to the via diameter and the thermal mismatch strain. Thinner wafers with smaller aspect ratios show larger ERRs. Changing the via geometry from a fully filled via to an annular via leads to lower ERR. FEA results also show that certain material combinations have lower thermal mismatch strains, thus less prone to delamination.

Practical implications

The results and approach presented in this paper can guide the design and development of more reliable 2.5 D glass interposers.

Originality/value

This paper represents the first attempt to comprehensively evaluate the impact of design and material selection on the interfacial reliability of TGVs.

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Article
Publication date: 11 February 2021

Yongxing Guo, Min Chen, Li Xiong, Xinglin Zhou and Cong Li

The purpose of this study is to present the state of the art for fiber Bragg grating (FBG) acceleration sensing technologies from two aspects: the principle of the measurement…

1014

Abstract

Purpose

The purpose of this study is to present the state of the art for fiber Bragg grating (FBG) acceleration sensing technologies from two aspects: the principle of the measurement dimension and the principle of the sensing configuration. Some commercial sensors have also been introduced and future work in this field has also been discussed. This paper could provide an important reference for the research community.

Design/methodology/approach

This review is to present the state of the art for FBG acceleration sensing technologies from two aspects: the principle of the measurement dimension (one-dimension and multi-dimension) and the principle of the sensing configuration (beam type, radial vibration type, axial vibration type and other composite structures).

Findings

The current research on developing FBG acceleration sensors is mainly focused on the sensing method, the construction and design of the elastic structure and the design of a new information detection method. This paper hypothesizes that in the future, the following research trends will be strengthened: common single-mode fiber grating of the low cost and high utilization rate; high sensitivity and strength special fiber grating; multi-core fiber grating for measuring single-parameter multi-dimensional information or multi-parameter information; demodulating equipment of low cost, small volume and high sampling frequency.

Originality/value

The principle of the measurement dimension and principle of the sensing configuration for FBG acceleration sensors have been introduced, which could provide an important reference for the research community.

Details

Sensor Review, vol. 41 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

Available. Open Access. Open Access
Article
Publication date: 28 April 2022

Shichao Jiang, Xinliang Lu, Hongliang Wang, Kai Song and Yuanyuan Jiang

Detection of hidden defects of aluminum alloy plate with damping coating is a challenging problem. At present, only a few non-destructive testing methods exist to address this…

753

Abstract

Purpose

Detection of hidden defects of aluminum alloy plate with damping coating is a challenging problem. At present, only a few non-destructive testing methods exist to address this engineering problem. Without the restriction of skin effect, remote field eddy current (RFEC) overcomes the interference caused by the damping coating. The RFEC, which has potential advantages for detecting the hidden defects of aluminum plate with damping coating, can penetrate the metal plate to detect buried depth defects. This study aims to test how thick the RFEC sensor can penetrate the metal plate to detect the buried defects.

Design/methodology/approach

The magnetic field distribution characteristics are analyzed, the magnetic field intensity distribution is calculated, and the structure and parameters of the coil, magnetic circuit and shielding damping are determined through the two- and three-dimensional finite element simulation methods. Optimal excitation frequency is obtained, and the distance between the excitation coil and detection coil is determined by analyzing the relationship between excitation frequency and remote field points.

Findings

Simulation and experimental results verify the feasibility of applying the RFEC detection technology in detecting the hidden defects of aluminum alloy plate with damping coating.

Originality/value

In this paper, the RFEC testing model of hidden defects in aluminum plate sample with damping coating is established by using the finite element method.

Details

Sensor Review, vol. 42 no. 4
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 3 January 2017

Kouame Joseph Arthur Kouame, Fuxing Jiang and Zhu Sitao

In rural regions, mining is an activity that employs many people due to the fact that the barriers to entry are sometimes trivial, with very low technology, capital fund, and no…

712

Abstract

Purpose

In rural regions, mining is an activity that employs many people due to the fact that the barriers to entry are sometimes trivial, with very low technology, capital fund, and no specialized skills required. Many people including children are engaged in artisanal mining in Ivory Coast because they can earn higher incomes in mining than through other traditional activities such as agriculture, which is the main activity in the country. Artisanal mining contributes to reduce abject poverty prevalent in the country and it offers many others opportunities. However, this activity has many negative social impacts. Local people including miners are risking their lives everyday as they are exposed to unsanitary conditions, prostitution, chemical contaminants, and alcoholism, and also due to the large degradation of lands. The paper aims to discuss these issues.

Design/methodology/approach

All the data collected during this study were analyzed before some of it was corrected. For data analysis and interpretation, the authors used Word and Excel and other software, and other statistical tools for maps, graphs, and tables.

Findings

The main objective of this paper is to understand how artisanal gold mining in the Ivory Coast affects local livelihoods and the environment.

Research limitations/implications

This study was carried out during the author’s study in China. The data collection between the two countries was too difficult due to the long distance. Many times the network was not reliable for any call and discuss with miners when we are not in the country. The hesitation of miners to give real information to the authors was also a main problem because most of them are illegal miners. Some of the guided questionnaires stayed without feedback for almost three months. The production was sold on a day-to-day basis by the miners in the illegal mining sites, so the authors could not obtain with precision the monthly and annual production to calculate income of the miners.

Originality/value

Some key recommendations for addressing artisanal mining activities in order to have a good option for sustainable management of mineral resources in the country are proposed.

Details

World Journal of Science, Technology and Sustainable Development, vol. 14 no. 1
Type: Research Article
ISSN: 2042-5945

Keywords

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Book part
Publication date: 20 January 2021

Yao Lixia

Abstract

Details

Energy Security in Times of Economic Transition: Lessons from China
Type: Book
ISBN: 978-1-83982-465-4

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Book part
Publication date: 21 November 2018

Lloyd Ling and Zulkifli Yusop

The US Department of Agriculture (USDA), Soil Conservation Services (SCS) rainfall-runoff model has been applied worldwide since 1954 and adopted by Malaysian government agencies…

Abstract

The US Department of Agriculture (USDA), Soil Conservation Services (SCS) rainfall-runoff model has been applied worldwide since 1954 and adopted by Malaysian government agencies. Malaysia does not have regional specific curve numbers (CN) available for the use in rainfall-runoff modelling, and therefore a SCS-CN practitioner has no option but to adopt its guideline and handbook values which are specific to the US region. The selection of CN to represent a watershed becomes subjective and even inconsistent to represent similar land cover area. In recent decades, hydrologists argue about the accuracy of the predicted runoff results from the model and challenge the validity of the key parameter, initial abstraction ratio coefficient (λ) and the use of CN. Unlike the conventional SCS-CN technique, the proposed calibration methodology in this chapter discarded the use of CN as input to the SCS model and derived statistically significant CN value of a specific region through rainfall-runoff events directly under the guide of inferential statistics. Between July and October of 2004, the derived λ was 0.015, while λ = 0.20 was rejected at alpha = 0.01 level at Melana watershed in Johor, Malaysia. Optimum CN of 88.9 was derived from the 99% confidence interval range from 87.4 to 96.6 at Melana watershed. Residual sum of square (RSS) was reduced by 79% while the runoff model of Nash–Sutcliffe was improved by 233%. The SCS rainfall-runoff model can be calibrated quickly to address urban runoff prediction challenge under rapid land use and land cover changes.

Details

Improving Flood Management, Prediction and Monitoring
Type: Book
ISBN: 978-1-78756-552-4

Keywords

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