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Article
Publication date: 7 May 2019

Yuankai Zhou, Xue Zuo and Hua Zhu

Running-in is a transient process prior to steady state and of great importance for mechanical performance. To reveal the fractal behavior in the running-in process, the…

103

Abstract

Purpose

Running-in is a transient process prior to steady state and of great importance for mechanical performance. To reveal the fractal behavior in the running-in process, the steel-on-steel friction and wear tests were performed.

Design/methodology/approach

The friction coefficient, friction temperature, friction noise and vibration were recorded, and the surface profile of lower sample was measured on line. The signals and profiles were characterized by correlation dimension and box-counting dimension, respectively.

Findings

The signals have the consistent fractal evolvement law, that is, the correlation dimension increases and tends to a stable value. The box-counting dimension of one surface becomes close to that of the other surface. The running-in process can be interpreted as a process in which the fractal dimension of friction signals increases, and the counter surfaces spontaneously adapt to and modify each other to form a spatial ordered structure.

Originality/value

The results reveal the running-in behavior from a new perspective.

Details

Industrial Lubrication and Tribology, vol. 71 no. 4
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 11 June 2021

Minglong Peng, Yuankai Zhou and Xue Zuo

The purpose of this paper is to study the dynamic features of friction coefficient during running-in state based on recurrence analysis, so as to recognize the running-in state of…

139

Abstract

Purpose

The purpose of this paper is to study the dynamic features of friction coefficient during running-in state based on recurrence analysis, so as to recognize the running-in state of crankshaft journal bearings.

Design/methodology/approach

The friction coefficient was measured in the friction experiments and the dynamic features are analyzed by recurrence plots (RPs), unthreshold recurrence plots (URPs) and recurrence quantification analysis.

Findings

During the running-in process, RPs have gone through disrupted patterns, drift patterns and homogeneous patterns successively. URP shows that the phase trajectory spirals in the disrupted pattern gradually converge in the drift pattern and remain stable in the homogeneous pattern. Three independent measures, recurrence rate, entropy and laminarity, are chosen to characterize friction coefficient from the perspective of point, diagonal line and vertical line structures of the RPs.

Originality/value

The results provide a feasible way to monitor the running-in process and recognize the running-in state.

Details

Industrial Lubrication and Tribology, vol. 73 no. 5
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 18 January 2024

Minglang Zhang, Xue Zuo and Yuankai Zhou

The purpose of this paper is to reveal the dynamic contact characteristics of the slip ring. Dynamic contact resistance models considering wear and self-excited were established…

91

Abstract

Purpose

The purpose of this paper is to reveal the dynamic contact characteristics of the slip ring. Dynamic contact resistance models considering wear and self-excited were established based on fractal theory.

Design/methodology/approach

The effects of tangential velocity, stiffness and damping coefficient on dynamic contact resistance are studied. The relationships between fractal parameters, wear time and contact parameters are revealed.

Findings

The results show that the total contact area decreases with the friction coefficient and fractal roughness under the same load. Self-excited vibration occurs at a low speed (less than 0.6 m/s). It transforms from stick-slip motion at 0.4 m/s to pure sliding at 0.5 m/s. A high stiffness makes contact resistance fluctuate violently, while increasing the damping coefficient can suppress the self-excited vibration and reduce the dynamic contact resistance. The fractal contact resistance model considering wear is established based on the fractal parameters models. The validity of the model is verified by the wear tests.

Originality/value

The results have a great significance to study the electrical contact behavior of conductive slip ring.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-09-2023-0300/

Details

Industrial Lubrication and Tribology, vol. 76 no. 2
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 15 September 2022

Zhiyong Wang, Yuankai Zhou and Xue Zuo

The purpose of this paper is to study the tribological effect of zinc borate ultrafine powder (ZBUP) oil additive on the running-in quality.

50

Abstract

Purpose

The purpose of this paper is to study the tribological effect of zinc borate ultrafine powder (ZBUP) oil additive on the running-in quality.

Design/methodology/approach

The running-in quality was assessed by friction coefficient and surface topography. Fractal parameters including fractal dimension, the width of multifractal, the multifractal difference, multifractal parameters, phase trajectory and correlation dimension were used to extract the nonlinear characteristics of surface topography and friction coefficient.

Findings

When the ZBUP additive was added, the convergence degree of the phase trajectory and the stability of the running in were higher than that of base oil. It indicates that the ZBUP additive can improve the running-in quality of sliding bearing. Besides, the ZBUP additive can shorten the running-in time. A boundary protective film, which has good friction-reducing and anti-wear effects, was generated on the surface when the ZBUP additive was added.

Originality/value

The results have a great significance to improve the running-in quality and prolong the service life of the sliding bearing.

Details

Industrial Lubrication and Tribology, vol. 74 no. 10
Type: Research Article
ISSN: 0036-8792

Keywords

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Book part
Publication date: 14 December 2023

Addisalem Tebikew Yallew and Paul Othusitse Dipitso

In an ever-interconnected world dominated by discourses on the internationalization and marketization of higher education, concerns related to language and employability have been…

Abstract

In an ever-interconnected world dominated by discourses on the internationalization and marketization of higher education, concerns related to language and employability have been the focus of recent debates. There is, however, a dearth of research investigating how these dimensions relate to one another in recent comparative and international higher education research. By focusing on how issues related to language and employability have been presented in recent higher education research worldwide, this chapter aims to contribute to our understanding of this concern. To achieve this goal, we conducted a scoping literature review using the Web of Science, Scopus, and the Education Resources Information Center (ERIC) databases, considering the years 2011–2020. The findings, perhaps not surprisingly, suggested that language skills are perceived to be valued by both graduates and employers though the discussions predominantly focused on one language, English. The research focus on English for employability in Anglophone contexts is understandable. However, the fact that the trend is observed in contexts where the language is not the primary or official language seems to indicate the influence of internationalization of higher education and global labor markets primarily dominated by English. The literature also suggested that (English) language training in higher education programs needs to move from solely linguistic and qualification-related content areas to a broader sphere of English for communication purposes that cover both specialized disciplinary content and broader generic employability skills. Considering this finding, we suggest that higher education systems and institutions incorporate recent developments in English for occupational purposes in their curriculum. We also recommend that there needs to be a shift from the overwhelmingly English language-dominated discussions to more inclusive research that assesses the impact of other dominant languages on employability-related concerns.

Details

Annual Review of Comparative and International Education 2022
Type: Book
ISBN: 978-1-83753-738-9

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Article
Publication date: 1 August 2023

Youxi Zhang, Yu Liu, Rui Yu, Jian Zuo and Na Dong

Prefabricated construction (PC) can benefit construction industry due to its high efficiency, energy saving, consumption reduction and safety. However, the high capital cost is a…

330

Abstract

Purpose

Prefabricated construction (PC) can benefit construction industry due to its high efficiency, energy saving, consumption reduction and safety. However, the high capital cost is a critical challenge hindering its development in China. The collaboration of PC stakeholders is conducive to improving cost management efficiency and optimizing resource allocation which has been ignored in previous studies. Therefore, this study aims to explore the collaboration paths of stakeholders in the process of solving critical cost influencing factors (CIFs) of PC to reduce costs.

Design/methodology/approach

Firstly, 25 CIFs and five main stakeholders that affect PC capital cost were identified through literature research and expert interviews. Then, questionnaires were used to investigate the relationship between stakeholders and CIFs from the perspectives of three stakeholder attributes of proximity, attitude and power, respectively. Finally, based on the survey data, three stakeholder-CIF networks from three attributes perspective and a comprehensive network were constructed and used for subsequent social network analysis.

Findings

(1) Stakeholders mainly show willingness and potential to collaborate on organization and management factors; (2) More stakeholders pay attention to incentive policies and the setting of prefabrication rates and assembly rates, while all stakeholders have the right to facilitate information and resource sharing in the PC supply chain; (3) The comprehensive network shows a core-periphery structure. As core stakeholders, contractor, designer and manufacturer are more likely to actively manage the 14 core CIFs.

Originality/value

This paper innovatively combined stakeholder and cost management in PC, and used two-mode network based on three stakeholder perspectives to reveal the collaboration potential and motivation of stakeholders in PC cost management. The findings not only provide guidance for stakeholders to find potential partners and optimize resource allocation in solving specific cost issues, but also facilitate stakeholders' sustainable collaboration to achieve PC's cost performance.

Details

Engineering, Construction and Architectural Management, vol. 32 no. 1
Type: Research Article
ISSN: 0969-9988

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Article
Publication date: 12 January 2021

Qing Xie

In light of university business English pedagogical innovation, this study reports an empirical study with 66 English major participants.

1016

Abstract

Purpose

In light of university business English pedagogical innovation, this study reports an empirical study with 66 English major participants.

Design/methodology/approach

The study uses online survey and participant observation to investigate their practice-oriented motivation and needs, the perceptions of using vocational education and training pedagogy in business English teaching and the learning outcomes in a Chinese university context.

Findings

The study found participants with motivations to learn business and trade knowledge, develop practice-oriented abilities and the preferences of learning flexibly and autonomously. For the perceptions of using vocational education and training pedagogy, simulations of meetings and negotiations were recommended and the job-based competency development model was useful. Workplace simulation was also particularly suggested to bridge the gap between classroom and workplace. For learning outcomes, writing practices and workplace simulation were considered particularly useful. The learning gains were found in international trade correspondence writing. While the intention of continuing learning business English correspondence writing was identified, more opportunities should be created for more practice-oriented activities, such as internship or corporate visit.

Originality/value

Informed by vocational education and training theory, the study has important pedagogical, theoretical and policy implications for business English teaching in both China and worldwide contexts.

Details

Education + Training, vol. 63 no. 2
Type: Research Article
ISSN: 0040-0912

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Article
Publication date: 13 August 2024

Muwen Wang

This paper tests if there exists a subjective well-being gap between informal workers in the informal and formal sectors in urban China, and explores the mechanisms behind such…

72

Abstract

Purpose

This paper tests if there exists a subjective well-being gap between informal workers in the informal and formal sectors in urban China, and explores the mechanisms behind such differences.

Design/methodology/approach

The author develops a simple theoretical model to analyze the effects of the employment sector and work time flexibility on workers' happiness and conducts a descriptive study to examine the relationship between employment type and subjective well-being using the China General Social Survey (CGSS) 2010, 2013, 2015 and 2017 datasets, a nationally representative sample.

Findings

The results show that only dependent informal work in the formal sector impairs workers' happiness, while the effect of independent informal work is not statistically significant. The potential mechanisms suggest that independent informal workers have higher working time flexibility and can work more hours to increase their earnings, which increases their subjective well-being. However, it is difficult for dependent informal workers to earn more by working more hours due to poor working time flexibility.

Originality/value

This study indicates that informal workers in the formal sector have lower subjective well-being in urban China and deserve more attention from policymakers. The author also suggests that increasing working time flexibility and encouraging self-employment can contribute to the welfare of informal workers.

Details

International Journal of Manpower, vol. 45 no. 9
Type: Research Article
ISSN: 0143-7720

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Article
Publication date: 22 September 2021

Sylvia Veronica Siregar and Siti Nurwahyuningsih Harahap

The purpose of this study is to examine the effect of business uncertainty on the information technology (IT) governance of listed firms in Indonesia.

702

Abstract

Purpose

The purpose of this study is to examine the effect of business uncertainty on the information technology (IT) governance of listed firms in Indonesia.

Design/methodology/approach

The samples are listed firms in Indonesia Stock Exchange for the years 2015–2018. Total observations are 1,215 firm years. The authors used the random effect panel regression to test the hypotheses.

Findings

The authors find that business uncertainty has a significant positive association with IT governance, consistent with the prediction. Companies with higher business uncertainty are in higher demand for implementing IT governance.

Originality/value

The authors have not found previous studies that examine business uncertainty as to the determinant of IT governance. The authors also examined the IT governance in Indonesia, one of the emerging countries. Most previous studies on IT governance were conducted in developed countries, which results may not be generalized to emerging countries.

Details

Journal of Financial Reporting and Accounting, vol. 21 no. 2
Type: Research Article
ISSN: 1985-2517

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Article
Publication date: 19 January 2022

Yu Liu, Rui-Dong Chang, Jian Zuo, Feng Xiong and Na Dong

Prefabricated construction (PC) will play a vital role in the transformation and upgrading of the construction industry in the future. However, high capital cost is currently one…

1147

Abstract

Purpose

Prefabricated construction (PC) will play a vital role in the transformation and upgrading of the construction industry in the future. However, high capital cost is currently one of the biggest obstacles to the application and promotion of PC in China. Clarifying the factors that affect the PC cost from the perspectives of stakeholders and exploring key cost control paths help to achieve effective cost management, but few studies have paid enough attention to this. Therefore, this research aims to explore the critical cost influencing factors (CIFs) and critical stakeholders of PC based on stakeholder theories and propose corresponding strategies for different stakeholders to reduce the cost of PC.

Design/methodology/approach

Based on the stakeholder theory and social network theory, literature review and two rounds of expert interviews were used to obtain the stakeholder-associated CIFs and their mutual effects, then the consistency of the data was tested. After that, social network analysis was applied to identify the critical CIFs, critical interaction and key stakeholders in PC cost control and mine the influence conduction paths between CIFs.

Findings

The results reveal that the cognition and attitude of developer and relevant standards and codes are the most critical CIFs while the government, developer and contractor are crucial to the cost control of PC. The findings further suggest that measures should be taken to reduce the transaction costs of the developer, and the contractor ought to efficiently apply information technology. Moreover, the collaborative work between designer and manufacturer can avoid unnecessary cost consumption.

Originality/value

This research combines stakeholder management and cost management in PC for the first time and explores the effective cost control paths. The research results can contribute to clarifying the key points of cost management for different stakeholders and improving the cost performance of PC projects.

Details

Engineering, Construction and Architectural Management, vol. 30 no. 2
Type: Research Article
ISSN: 0969-9988

Keywords

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