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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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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).

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.

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.

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.

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.

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.

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.

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.

This paper aims to capture tail dependence between sentiment index and Shanghai composite index (SCI) by proposing a sentiment index based on text mining.

Online text mining and the Copula model were used in this study.

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.

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.

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.

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.

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.

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.

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.

To realise the shared development of the digital economy, people need to transcend the capital logic and advocate the logic of cooperative development, i.e. “co-construction, benefit-sharing and co-governance”. This study aims to discuss the aforementioned statement.

Platform economy is a new economic form produced by the transformation of the social production patterns in the era of digital capitalism. In the neo-imperialist stage, a new stage of capitalist development, capital logic promotes the global expansion of the platform economy and influences its development process, organisational form, contradictions and dilemmas and internal transcendence. Having the spatiotemporal chain of capital circulation repaired, the globalisation of the platform economy is reshaping how the means of production are combined with labour, affecting the local changes in the general relations of production and “international relations of production”.

In the accumulation of digital capitalism, the social contradictions and fundamental contradictions in the capitalist world have been further intensified, making exploitation, income distribution gap, monopoly and other problems increasingly severe. The imbalance and inequality in the global development of the digital economy are increasingly prominent.

Regarding the global governance of the digital economy, China, as a major responsible country, will strive to encourage all countries to co-build a community with a shared future in cyberspace. In the new international development pattern of digital economy globalisation, China must take effective measures to actively safeguard its national security and development interests to meet specific challenges.