WenRuo Zhu, ZhongXin Gao, YongJun Tang, JianGuang Zhang and Li Lu
The purpose of this paper is to analyze the ability of turbulence models to model the flow field in the runner of a Francis turbine. Although the complex flow in the turbine can…
Abstract
Purpose
The purpose of this paper is to analyze the ability of turbulence models to model the flow field in the runner of a Francis turbine. Although the complex flow in the turbine can be simulated by CFD models, the prediction accuracy still needs to be improved. The choice of the turbulence model is one key tool that affects the prediction accuracy of numerical simulations.
Design/methodology/approach
This study used the SST k-w and RNG k-e turbulence models, which can both accurately predict complex flow fields in numerical simulations, to simulate the flow in the entire flow passage of a Francis turbine with the results compared against experimental data for the performance and blade pressure distribution in the turbine to evaluate the applicability of the turbulence models.
Findings
The results show that the SST k-w turbulence model more accurately predicts the turbine performance than the RNG turbulence model. However, the blade surface pressures predicted by the SST k-w turbulence model were basically identical to those predicted by the RNG k-e turbulence model, with both accurately predicting the experimental data.
Research limitations/implications
Due to the lack of space, the method used to measure the blade surface pressure distributions is not introduced in this paper.
Practical implications
Turbine performance and flow field pressure in the runner, which are the basis of turbine preliminary performance judgment and optimization through CFD, can be used to judge the rationality of the turbine runner design. The paper provides an evidence for the turbulence selection in numerical simulation to predict turbine performance and flow field pressure in the runner and improves the CFD prediction accuracy.
Originality/value
This paper fulfils a test of the flow field pressure in the runner, which provide an evidence for judge the adaptability of turbulence model on the flow field in runner. And this paper also provides important evaluations of two turbulence models for modeling the flow field pressure distribution in the runner of a Francis turbine to improve the accuracy of CFD models for predicting turbine performance.
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This paper aims to analyse how both Lin’s birthplace identity and his Christian identity contributed to his fruitful public career and to ascertain which identity became the most…
Abstract
Purpose
This paper aims to analyse how both Lin’s birthplace identity and his Christian identity contributed to his fruitful public career and to ascertain which identity became the most significant.
Design/methodology/approach
Archival research is the main method used in this paper. The most important archives drawn from are the Daniel Tse Collection in the Special Collection and Archives of the Hong Kong Baptist University Library. Oral history has also been used in this paper to uncover more material that has not yet been discussed in existing scholarly works.
Findings
This paper argues that although Lin’s birthplace identity and social networks helped him to start his business career in Nam Pak Hong and develop into a leader in the local Chaozhou communities, these factors were insufficient to his becoming a respectable member of the Chinese elite in post-war Hong Kong. He became well known not because of his leading position in local Chaozhou communities or any great achievement he had obtained in business but because of his contribution to the development of Christian education. These achievements earned him a reputation as a “Christian educator”. Thus Lin’s Christian identity became more important than his birthplace identity in contributing to his successful public career.
Originality/value
This paper has value in showing how Christian influences interacted with various cultural factors in early Hong Kong. It also offers insights into Lin’s life and motivations as well as the history of the institutions he contributed to/founded. It not only furthers our understanding of the Chinese Christian business elite in early Hong Kong but also provides us with insights when further studying this group of people in other British colonies in Asia.
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The purpose of this paper is to provide a conceptual framework of staged development that examines strategies of domestic companies, government policies, and impacts of foreign…
Abstract
Purpose
The purpose of this paper is to provide a conceptual framework of staged development that examines strategies of domestic companies, government policies, and impacts of foreign multinational companies (MNCs) at different periods of catch‐up of latecomers.
Design/methodology/approach
A multi‐case approach is employed to examine four domestic telecom‐equipment companies that have significant impact on China's telecom‐equipment industry. They are: Huawei Technology Corporation (Huawei), Shenzhen Zhongxin Technology Corporation (ZTE), Datang Telecom Technology Corporation, Ltd (Datang), and Great Dragon Information Technology (GDT).
Findings
This paper identifies four distinct stages of the catching‐up process, featuring different institutional environment, government involvement, and the ensuing actions of foreign MNCs and domestic companies. During the initial stage, China's government decision of directly leapfrogging to the most advanced switch equipment had a profound impact, because it led to both heavy reliance on foreign MNCs and the pursuance of switch research and development (R&D) by domestic research institutes and new technology companies. The dominance of foreign MNCs is challenged during the growth stage, because several domestic companies ascended and gained the capability to produce large‐scale, stored program controls and the government directly leveraged support in R&D, marketing, and finance. Although many uncompetitive domestic companies failed during the filtration stage, the management training received from foreign MNCs and newly available financing options provided necessary resources for some domestic companies to survive and expand. Domestic leaders globalized their marketing, production, and R&D functions and to become MNCs themselves in the globalization stage, thus finalizing the catching‐up.
Social implications
The Chinese experiences shed light on late‐industrialization for other developing economies by suggesting that to catch‐up in high‐tech industries, government can become involved strategically to form a competitive and efficient market environment for innovation.
Originality/value
The paper proposes a new conceptual framework to analyze catching‐up of domestic companies as latecomers. This framework can be used to study catching‐up in other sectors in late‐industrializing countries.
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Kaimeng Zhang, Zhongxin Ni and Zhouyan Lu
This research paper aims to investigate the critical factors influencing the live commerce industry and their implications for Key Opinion Leaders (KOLs) and brands.
Abstract
Purpose
This research paper aims to investigate the critical factors influencing the live commerce industry and their implications for Key Opinion Leaders (KOLs) and brands.
Design/methodology/approach
The study comprehensively reviews previous research, develops relevant hypotheses and utilizes personal information from 66 anchors, along with data from 23,000 product links obtained from the backends of live commerce platforms.
Findings
The study emphasizes that KOLs with higher traffic significantly influence Gross Merchandise Volume (GMV). Intriguingly, KOLs with lower traffic levels exhibit a more pronounced effect on Return on Investment (ROI), highlighting their significance in driving profitability. Furthermore, the study explores the correlation between KOL hashtags and GMV/ROI and the intricate relationship between product types and KOL hashtags.
Practical implications
The findings significantly enhance the understanding of live shopping behavior and provide valuable insights for business management strategies. Practitioners can leverage this empirical evidence to make informed decisions, utilizing extensive data samples of KOLs and brands.
Originality/value
This research contributes unique insights into the live-streaming commerce industry using backend data from Live Streaming E-commerce platforms. The findings are more accurate based on market data than previous studies that relied on platform reviews or questionnaires. Additionally, this paper investigates the impact of KOLs on the performance of live e-commerce from three perspectives: GMV, ROI and hot-selling products.
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Ellen Efron Pimentel and Jinyun Liu
In this paper, we model histories of coresidence between two cohorts of urban Chinese couples, married during the Cultural Revolution and early market reform periods. Most…
Abstract
In this paper, we model histories of coresidence between two cohorts of urban Chinese couples, married during the Cultural Revolution and early market reform periods. Most research on coresidence pictures families cross‐sectionally, but nuclear households are a natural part of extended coresidence systems that prefer stem family arrangements. We study histories of coresidence to determine what predicts ever having coresided with the husband’s parents, comparing the predictive power of modernization theory to the impact of demographic change, the availability of household members, and the resources and needs of each generation. While married children’s needs for childcare do not propel them into coresidence, they strongly predict the likelihood of staying coresident.
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Yingxiang Zhao, Junde Guo, Xiaoni Yan, Shan Du, Min Gong, Biao Sun, Junwen Shi and Wen Deng
The purpose of this paper is to investigate the friction and wear mechanisms in copper-based self-lubricating composites with MoS2 as the lubricating phase, which provides a…
Abstract
Purpose
The purpose of this paper is to investigate the friction and wear mechanisms in copper-based self-lubricating composites with MoS2 as the lubricating phase, which provides a theoretical basis for subsequent research on high-performance copper-based self-lubricating materials.
Design/methodology/approach
Friction tests were performed at a speed of 100 r/min, a load of 10 N, a friction radius of 5 mm and a sliding speed of 30 min. Friction experiments were carried out at RT-500°C. The phase composition of the samples was characterized by X-ray diffraction of Cu Ka radiation, and the microstructure, morphology and elemental distribution were characterized by scanning electron microscopy and energy dispersive spectroscopy. Reactants and valences formed during the wear process were analyzed by X-ray photoelectron spectroscopy.
Findings
The addition of MoS2 can effectively improve friction-reducing and anti-wear action of the matrix, which is beneficial to form a lubricating film on the sliding track. After analyzing different changing mechanism of the sliding tracks, the oxides and sulfides of MoS2, MoO2, Cu2O, CuO and Ni(OH)2 were detected to form a synergetic lubricating film on the sliding track, which is responsible for the excellent tribological properties from room to elevated temperature.
Research limitations/implications
For self-lubrication Cu–Sn–Ni–MoS2 material in engineering field, there are still few available references on high-temperature application.
Practical implications
This paper provides a theoretical basis for the following research on copper-based self-lubricating materials with high performance.
Originality/value
With this statement, the authors hereby certify that the manuscript is the results of their own effort and ability. They have indicated all quotes, citations and references. Furthermore, the authors have not submitted any essay, paper or thesis with similar content elsewhere. No conflict of interest exits in the submission of this manuscript.
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While there is a growing literature on the reform of accounting practices and standards in China, relatively little has been written about practitioners. But it is they who will…
Abstract
While there is a growing literature on the reform of accounting practices and standards in China, relatively little has been written about practitioners. But it is they who will be doing the work!This paper traces changes in the organisation and regulation of accountancy practitioners in China during the twentieth century, with particular focus on the post‐1978 period. It highlights the changing balance, over time, between state, market and community as principles for organising practitioners. Nothwithstanding the significant trend towards a market economy, we are still in the midst of a period of transformation both in Chinese society as a whole and accountancy in particular. At present the state maintains quite a degree of influence over Chinese accountancy through its control of Chinese accountants.
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Gan Zhan, Zhenyu Zhang, Zhihua Chen, Tianzhen Li, Dong Wang, Jigang Zhan and Zhengang Yan
This paper aims to focus on the spatial docking task of unmanned vehicles under ground conditions. The docking task of military unmanned vehicle application scenarios has strict…
Abstract
Purpose
This paper aims to focus on the spatial docking task of unmanned vehicles under ground conditions. The docking task of military unmanned vehicle application scenarios has strict requirements. Therefore, how to design a docking robot mechanism to achieve accurate docking between vehicles has become a challenge.
Design/methodology/approach
In this paper, first, the docking mechanism system is described, and the inverse kinematics model of the docking robot based on Stewart is established. Second, the genetic algorithm-based optimization method for multiobjective parameters of parallel mechanisms including workspace volume and mechanism flexibility is proposed to solve the problem of multiparameter optimization of parallel mechanism and realize the docking of unmanned vehicle space flexibility. The optimization results verify that the structural parameters meet the design requirements. Besides, the static and dynamic finite element analysis are carried out to verify the structural strength and dynamic performance of the docking robot according to the stiffness, strength, dead load and dynamic performance of the docking robot. Finally, taking the docking robot as the experimental platform, experiments are carried out under different working conditions, and the experimental results verify that the docking robot can achieve accurate docking tasks.
Findings
Experiments on the docking robot that the proposed design and optimization method has a good effect on structural strength and control accuracy. The experimental results verify that the docking robot mechanism can achieve accurate docking tasks, which is expected to provide technical guidance and reference for unmanned vehicles docking technology.
Originality/value
This research can provide technical guidance and reference for spatial docking task of unmanned vehicles under the ground conditions. It can also provide ideas for space docking missions, such as space simulator docking.
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Keqing Zhong and Jae Park
This policy review paper is an analysis of the Double Reduction Policy (DRP) of China that was promulgated in July 2021. It looks into its rationale as well as different…
Abstract
Purpose
This policy review paper is an analysis of the Double Reduction Policy (DRP) of China that was promulgated in July 2021. It looks into its rationale as well as different stakeholders' early reactions to the policy.
Design/methodology/approach
Critical policy analysis (CPA) method was used to identify (1) the artefacts, such as language, objects and acts, that were significant carriers of the DRP; (2) communities of meaning, interpretation, speech and practice that are relevant to the DRP and its implementation; (3) the local discourses relevant to the DRP; and (4) the tension points and their conceptual sources (affective, cognitive and/or moral) by different DRP stakeholders. As per the comparative education field, this paper compares the pre-DRP and post-DRP periods to tease out how the policy affects different stakeholders of education.
Findings
The DRP in China could be attributed to diverse factors such as demography, socialist economic and developmental visions and manpower structure. The implementation of the DRP has generated uneven reactions among different stakeholders and geographical regions both in speed and scale. While education stakeholders have no choice but to adopt the policy, they face challenges derived from a sudden halt of private educational resources and subsequent increased duties of parents and schools.
Originality/value
The significance of this early policy analysis lies in offering an insight into education development in China by analysing and deliberating the DRP from different perspectives.
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Juan Shan and Dominique R. Jolly
The purpose of this paper is to discuss the development of high‐tech industry and the dynamics of technological learning, innovation, entrepreneurship in China through the…
Abstract
Purpose
The purpose of this paper is to discuss the development of high‐tech industry and the dynamics of technological learning, innovation, entrepreneurship in China through the telecom‐equipment industry.
Design/methodology/approach
The paper derives a number of research propositions from the literature and then uses four case studies to show how domestic firms narrow their technological gap in different stages of catch‐up and how these firms have been influenced by their innovation capabilities to catch up to the multinationals.
Findings
The major findings of the paper may be summarized as follows. First, the innovation capability and self‐developed technologies have been the key to leading domestic firms in catching‐up with the MNCs. Second, leading domestic firms mainly depend on in‐house R&D development, supplemented with external alliance to build their innovation capability. Third, there are two different catching‐up patterns in China's telecom‐equipment industry. One is “path‐following” catching‐up in global system for mobile communication driven by using new technology in low‐end market. The other is “leapfrogging” catching‐up in the development of phone digital switches and China's own 3G standard (time division – synchronous code division multiple access). However, it seems that the leapfrogging strategy will meet more challenges and problems than the path‐following strategy.
Originality/value
Based on the previous researches about technological learning, innovation and catch‐up in the newly industrializing economies, the paper provides a comprehensive elaboration in Chinese telecommunication industry by using case study approach in an original way.