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1 – 10 of 14Boyi Li, Miao Tian, Xiaohan Liu, Jun Li, Yun Su and Jiaming Ni
The purpose of this study is to predict the thermal protective performance (TPP) of flame-retardant fabric more economically using machine learning and analyze the factors…
Abstract
Purpose
The purpose of this study is to predict the thermal protective performance (TPP) of flame-retardant fabric more economically using machine learning and analyze the factors affecting the TPP using model visualization.
Design/methodology/approach
A total of 13 machine learning models were trained by collecting 414 datasets of typical flame-retardant fabric from current literature. The optimal performance model was used for feature importance ranking and correlation variable analysis through model visualization.
Findings
Five models with better performance were screened, all of which showed R2 greater than 0.96 and root mean squared error less than 3.0. Heat map results revealed that the TPP of fabrics differed significantly under different types of thermal exposure. The effect of fabric weight was more apparent in the flame or low thermal radiation environment. The increase in fabric weight, fabric thickness, air gap width and relative humidity of the air gap improved the TPP of the fabric.
Practical implications
The findings suggested that the visual analysis method of machine learning can intuitively understand the change trend and range of second-degree burn time under the influence of multiple variables. The established models can be used to predict the TPP of fabrics, providing a reference for researchers to carry out relevant research.
Originality/value
The findings of this study contribute directional insights for optimizing the structure of thermal protective clothing, and introduce innovative perspectives and methodologies for advancing heat transfer modeling in thermal protective clothing.
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Guilin Wang, Fan Sun, Runqiu Wang, Liang Zhang, Tianci Cao and Boyi Li
The material point method (MPM)is a particle-based numerical method suitable for solid–liquid simulation and large deformation problems. However, MPM is generally used in solid…
Abstract
Purpose
The material point method (MPM)is a particle-based numerical method suitable for solid–liquid simulation and large deformation problems. However, MPM is generally used in solid deformation at present, to develop a multi-physics coupling MPM; the purpose of this study is to extend the MPM to simulate the heat and fluid flow and address the thermal-hydrological (TH) coupling problems.
Design/methodology/approach
The porous medium was discretized into two sets of Lagrangian points, and the motion of fluid points follows the Darcy’s law. Two sets of heat transport equations were established for the heat conduction and heat exchange in the pore fluid and solid skeleton. Fractures were considered by adding the porosity gradient term in the governing equations; also a transition function was introduced to smoothen the fracture boundary.
Findings
Four cases of heat and fluid flow in porous medium and fractures were presented to verify the feasibility of the proposed method. And the effects of fractures on heat and fluid flow were investigated. Additionally, a case of geothermal extraction was solved and the importance of the interstitial convective heat transfer coefficient was analyzed.
Originality/value
The proposed method extends the conventional MPM, using two sets of material points and two sets of heat transport equations to simulate the heat and fluid flow and address the TH coupling problems, which can be applied in both porous medium and fractures.
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Xiaobo Wang, Zhipeng Li, Wen Zhan, Jesong Tu, Xiaohua Zuo, Xiangyi Deng and Boyi Gui
This study aims to expand the reliability and special functions of lightweight materials for high-end equipment and green manufacturing, so that it is the first such research to…
Abstract
Purpose
This study aims to expand the reliability and special functions of lightweight materials for high-end equipment and green manufacturing, so that it is the first such research to carry out nano-composite technology of nickel-coated carbon nanotubes (Ni-CNTs)-based titanium-zirconium chemical conversion on aluminum alloy substrate.
Design/methodology/approach
Corrosion behavior of various coatings was investigated using dropping corrosion test, linear polarization and electrochemical impedance spectroscopy. The results showed that the corrosion resistance of the nano-composite conversion coatings was significantly improved to compare with the conventional titanium-zirconium conversion coating. The morphology and microdomain characteristics of the nano-composite conversion coatings were characterized by SEM/eds/EPMA, which indicated that the CNT or Ni-CNTs addition promoting the integrity coverage of coatings in a short time.
Findings
Surface morphology of titanium-zirconium (Ti-Zr)/Ni-CNT specimens exhibited smooth, compact and little pores. The nano-composite conversion coatings are mainly composed of Al, O, C and Ti elements and contain a small amount of F and Zr elements, which illuminated that CNT or Ni-CNT addition could co-deposit with aluminum and titanium metal oxides.
Originality/value
The study of corrosion resistance of nano-composite conversion coatings and the micro-zone film-formation characteristics would be provided theoretical support for the development of basic research on surface treatment of aluminum alloys.
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Zhigang Song, Qinxuan Gu and Boyi Wang
The purpose of this paper is to develop a measurement of creativity-oriented HRM systems that improve organizational creativity. This paper also aims to explore the mechanisms…
Abstract
Purpose
The purpose of this paper is to develop a measurement of creativity-oriented HRM systems that improve organizational creativity. This paper also aims to explore the mechanisms between them by investigating the mediating role of innovative culture and the moderating role of customer orientation.
Design/methodology/approach
The study uses a sample of 82 knowledge-intensive companies with 780 respondents consisting of 145 HR professionals, 512 core knowledge workers and 123 top managers in China. Exploratory factor analysis, confirmatory factor analysis and regression analysis are used to validate the measure of creativity-oriented HRM systems and test hypotheses.
Findings
This study finds that creativity-oriented HRM systems are composed of three dimensions, which are creative skill-enhancing practices, intrinsic motivation-enhancing practices and empowerment-enhancing practices. These practices significantly improve organizational creativity through innovative culture. Furthermore, customer orientation moderates the effect of innovative culture on organizational creativity in such a way that the positive relationship is stronger when customer orientation is high.
Originality/value
This study contributes to the strategic human resource management literature by developing and validating a measure of creativity-oriented HRM systems. Moreover, it also explores the mechanism between creativity-oriented HRM systems and organizational creativity based on a complementary perspective of innovativeness, which underlines the important mediating effect of innovative culture. More importantly, the authors propose the significance of absorbing knowledge and information from customers and put forward the moderating role that customer orientation plays, especially in an emerging country context such as China.
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This study aims to study the role of co-production among heterogenous actors to achieve a digital transformation for public service delivery. The importance of building legitimacy…
Abstract
Purpose
This study aims to study the role of co-production among heterogenous actors to achieve a digital transformation for public service delivery. The importance of building legitimacy and public value creation during the journey of adopting new technology is mainly discussed through analyzing the case of blockchain-based decentralized identity (DID) in South Korea (Korea).
Design/methodology/approach
Using a qualitative method, the conceptual framework for this study draws on public value theory that highlights co-production approaches on adoption and diffusion of new information system.
Findings
The results of this study provide empirical support for the claim that co-constructive and cross-sector partnership is critical to the adoption of blockchain-based DID and to maximize the value-in-use and increase citizens’ participation.
Originality/value
This study suggests a new perspective, which contributes to the information system literature and the phenomenological analysis by investigating co-constructive partnership among cross-sector organizations through the legitimacy-building process, which has not been much empirically researched.
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Xiaobo Wang, Wen Zhan and Boyi Gui
The purpose of this paper is to develop a chrome-free and phosphorus-free chemical conversion coating with good corrosion resistance, a novel chemical conversion coating was…
Abstract
Purpose
The purpose of this paper is to develop a chrome-free and phosphorus-free chemical conversion coating with good corrosion resistance, a novel chemical conversion coating was prepared by adding cerium nitrate hexahydrate and salicylic acid in the treatment solution containing titanium/zirconium ions on 6061 aluminum alloy.
Design/methodology/approach
Compared with the AA6061 aluminum alloy matrix, the self-corrosion potential of the conversion coating is significantly positively shifted, the self-corrosion current density is greatly reduced and its corrosion resistance is significantly improved. Morphology and composition of the conversion coatings were observed by scanning electron microscopy and energy-dispersive X-ray spectroscopy. The microdomain structure of conversion coatings at different formation stages was analyzed by electron probe microanalyzer.
Findings
An optimized preparation technique of titanium–zirconium chemical conversion coating for AA6061 aluminum alloy is obtained: H2TiF6 4 mL/L, H2ZrF6 0.4 mL/L, salicylic acid 0.35 g/L, Ce(NO3)3·6H2O 0.14 g/L, reaction temperature 30°C, reaction time 120 s and pH 4.0.
Originality/value
The coating forms on the Al(Fe)Si intermetallic compound, and Ce3+ is preferentially adsorbed on the intermetallic compound. The hydrolysis of Ce3+ causes the local pH of the solution to decrease, which promotes matrix dissolution and charge migration. As the microanode/microcathode reaction occurs, the local pH of the solution increases, and Al2O3/ZrO2/TiO2 begins to deposit on the surface of the metal substrate.
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Beatrice Audifasi Nyallu, Xiaopeng Deng and Melckzedeck Michael Mgimba
Knowledge loss (KL) is still an unfortunate fact, causing many challenges, including poor organisational performance, despite prior efforts to investigate knowledge retention…
Abstract
Purpose
Knowledge loss (KL) is still an unfortunate fact, causing many challenges, including poor organisational performance, despite prior efforts to investigate knowledge retention methods. Therefore, this study identifies early approaches to combat KL and poor organisational performance, shifting focus on employee personality traits.
Design/methodology/approach
Grounded on the social exchange theory (SET) cross-section data from 400 Chinese construction knowledge employees were used to investigate the role of internal work locus of control (IWLC) on job rotation (JR), KL and organisational performance. The data were analysed through IBM SPSS Statistics 25 and SmartPLS 4 software.
Findings
The results demonstrated that IWLC minimises KL and positively influences JR. Then, JR negatively influences KL and decreases in organisational performance. The negative mediating effect of JR in the relationship between IWLC, KL and decreased organisational performance were also found. Finally, KL proved to positively influence a decrease in organisational performance.
Research limitations/implications
This study contributes to the new understanding of individual behaviour and its influence on organisational outcome variables. Specifically, for ultimate KL prevention and organisational performance improvement, an organisation should understand its employees' behaviours to establish progressive collective learning and knowledge sharing.
Practical implications
This study contributes to the new understanding of individual behaviour and its influence on organisational outcome variables. Specifically, for ultimate KL prevention and organisational performance improvement, an organisation should understand its employees’ behaviours to establish progressive collective learning and knowledge sharing.
Originality/value
This study is the first attempt to explore the influence of personality traits in the early minimisation of KL, particularly the role of IWLC and JR in combating KL and improving organisational performance.
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Can Zhong Yao, Bo Yi Sun and Ji Nan Lin
This paper aims to capture tail dependence between sentiment index and Shanghai composite index (SCI) by proposing a sentiment index based on text mining.
Abstract
Purpose
This paper aims to capture tail dependence between sentiment index and Shanghai composite index (SCI) by proposing a sentiment index based on text mining.
Design/methodology/approach
Online text mining and the Copula model were used in this study.
Findings
First, the paper finds herding effect in the expression of investors’ sentiment from online text data, and the usage occurrence frequency of most vocabulary is less correlative with SCI. Second, given these two features, the paper uses weighted divide-and-conquer algorithm to construct a sentiment index. Finally, because of multivariate non-Gaussian joint distribution between them, the paper uses the Copula model to detect their tail dependences, and finds that both upper and lower tail dependences could have a significant influence between positive sentiment and SCI, with a higher probability on the upper one. Additionally, only the upper tail dependence exhibits the significant influence between negative sentiment and SCI.
Originality/value
This paper proposes a framework of constructing investment sentiment index with the weighted conquer-and-divide algorithm, and characterizes tail dependence between sentiment index and SCI. The implication can measure the environment of investment market of China and provide an empirical ground for bandwagon effect and bargain shopper effect.
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Okey Nwuke, Chizoba Nwoye and Nnaemeka Onoyima
In many countries (Nigeria inclusive), major components of job creation and economic growth, are driven by small and medium-sized businesses that are mostly family-owned. However…
Abstract
In many countries (Nigeria inclusive), major components of job creation and economic growth, are driven by small and medium-sized businesses that are mostly family-owned. However, over 50% of such businesses fail after intrafamily leadership transition. This chapter seeks to understand and explain the strategies that owners of medium-sized family-owned businesses explore in ensuring the sustainability of their business after a leadership transition from the founder. The focus is on three business leaders who sustained their family-owned businesses after a leadership transition from their founders. The conceptual framework is based on the transformational leadership theory. Data collection was from artefacts, company documents and semi-structured, face-to-face interviews. Analysis of data was supported by follow-up questions and member-checking to enhance the trustworthiness and credibility of the interpretations. Four themes that emerged were the founder's desire and support for transition, the preparation of successors or level of preparedness, trust and credibility of successors, and clarity of vision of both the founders and successors. Findings from this study may contribute to positive social change by providing leaders of African family-owned businesses with strategies for managing leadership transitions and ensuring the survival of the business after these transitions. Sustainability of family businesses might lead to job retention and creation, as well as enhance wellbeing and incomes of communities, family members and the African economy.
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Rare earths are essential materials for many high-tech industries critical to both economic development and national defense. China, the world's dominant supplier of rare earths…
Abstract
Purpose
Rare earths are essential materials for many high-tech industries critical to both economic development and national defense. China, the world's dominant supplier of rare earths, has recently been imposing stricter controls over its production and export. The purpose of this paper is to examine the domestic roots of the changes in China's rare earth industry production and exports in its three-decade rise to the current global monopoly.
Design/methodology/approach
This paper adopts the historical institutionalism approach to analyze the trajectory of industry and trade development. The author analyzes data collected from government whitepapers and reputed scholarly and news sources.
Findings
This paper argues that the Chinese rare earth industry has gone through three periods of development, in which the state attempted to control the market and industry through reformulating rules and institutions to achieve state goals. Domestic state institutions, combined with macroeconomic environment and state governance strategy shaped the three-decade experience of rare earth industry and trade development in China.
Originality/value
This paper builds on existing findings about Chinese state regulations to provide a novel analytical framework to analyze the role of the state in industry and trade development in the rare earth industry. The focus on a single strategic industry seldom studied in the current literature also provides ample empirical value to further scholarly understanding about this industry.
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