Zhenhua Zhang, Jiaxu Wang, Guangwu Zhou and Xin Pei
This paper aims to solve the lubrication failures in the turning arm bearing of RV reducer, give some help in perfecting the bearing structure design and provide theoretical basis…
Abstract
Purpose
This paper aims to solve the lubrication failures in the turning arm bearing of RV reducer, give some help in perfecting the bearing structure design and provide theoretical basis for the reducer’s performance improvement.
Design/methodology/approach
The paper establishes a mixed lubrication analysis model to study performance parameters. According to the discretization of parameters and iteration of equations, numerical simulation and theoretical analysis are achieved in computational process.
Findings
Considering influences of contact load, real rough surface and realistic geometry of RV reducer turning arm roller bearing, the mixed lubrication analysis model is established to study the ratio of oil film thickness, pressure distribution and maximum von Mises stress in different speeds, temperatures and fillets. The results of mixed lubrication show that reasonable round corner modification, increase in temperature and speed, decrease of surface roughness and lubricant types can improve the lubrication performance.
Originality/value
The mixed lubrication analysis model is established to study the influences of contact load, real rough surface and realistic geometry of RV reducer turning arm roller bearing. Different speed, temperature, lubricant and fillet modification are also considered in the research to analyze oil film thickness, pressure distribution and maximum von Mises stress. These studies can optimize structural design of bearing and direct engineer operations.
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Qiuwen Ma, Shan Li, Pei Xin Teo and Florence Yean Yng Ling
Compared with traditional approaches, integrated project delivery (IPD) improves project performance by enhancing integration. To adopt IPD, however, existing practices need to be…
Abstract
Purpose
Compared with traditional approaches, integrated project delivery (IPD) improves project performance by enhancing integration. To adopt IPD, however, existing practices need to be changed, which creates barriers to implementation. This study aims to identify the barriers to IPD practices in China and Singapore, whose practitioners show different types and levels of integration experience.
Design/methodology/approach
A questionnaire survey was administered to two groups of respondents: Chinese and Singaporean. The data were analyzed using three nonparametric techniques, including Wilcoxon signed-rank test, Mann-Whitney-Wilcoxon test, and Spearman rank correlation.
Findings
(1) Of 39 possible barriers, 36 were consistently felt by both Chinese and Singaporean practitioners with different backgrounds; (2) The Chinese group perceived more issues to be significant barriers than the Singaporean group; (3) The Singaporean group had more experience than the Chinese group in performing integration in five areas. This lessens some barriers to adopting IPD practices.
Originality/value
This study is important because it uncovers barriers to the effective implementation of IPD and shows the importance of certain types and levels of integration experience in overcoming these barriers. The results will be useful to practitioners planning to adopt IPD in China or Singapore.
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Wu Yan and Lisa Catherine Ehrich
The purpose of this paper is to provide an understanding of principal preparation and training in China by providing a background discussion of principal preparation in a number…
Abstract
Purpose
The purpose of this paper is to provide an understanding of principal preparation and training in China by providing a background discussion of principal preparation in a number of countries. As an illustration, it provides an overview of the curriculum used in the initial preparation of school principals at Beijing Normal University.
Design/methodology/approach
The paper draws mainly on writing and research from China, Australia and the USA to explore principal preparation and training in China.
Findings
In addition to providing a rich description of principal preparation in China, the paper's main findings comprise seven key challenges that confront China as it endeavours to provide quality principal preparation. These challenges include China's diversity and uneven social, cultural and educational development; limited resources in some regions throughout China; the place and importance of study tours for principal preparation; the teaching approach used to train principals; the process used for assessing principal learning during their training programs; the limited transfer of learning from the classroom to the school environment; and the timing of training for principals.
Practical implications
Each of the challenges arising here raises important practical implications for developers of principal training programs.
Originality/value
The paper paints a picture of principal preparation in China and raises a number of issues and challenges with which it continues to grapple. Of note is that China is not alone in facing some of these ongoing concerns.
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Pei Liu, Yu Ma, Xin Li, Caodie Peng and Yaoqi Li
Frontline service employees are often subjected to customer mistreatment and considerable studies have tested outcomes of customer mistreatment. However, the importance of its…
Abstract
Purpose
Frontline service employees are often subjected to customer mistreatment and considerable studies have tested outcomes of customer mistreatment. However, the importance of its antecedents is particularly underestimated. This meta-analytic paper aims to develop an overarching framework that identifies the antecedents of customer mistreatment as well as potential boundary conditions to account for observed variations reported in extant studies.
Design/methodology/approach
Comprehensive electronic and manual searches were performed to retrieve relevant studies on customer mistreatment, which yielded 125 articles, including 141 independent samples. Altogether, these studies included 40,151 participants. The data were analyzed through random-effect meta-analytic methods in R using the psychmeta package.
Findings
Three types of antecedents were identified. In particular, regarding employees’ demographic characteristics, age was found to be negatively correlated with customer mistreatment. Employees’ personality traits such as agreeableness, conscientiousness, positive affectivity, emotion regulation ability and self-efficacy were found to be negatively correlated with customer mistreatment, while neuroticism and negative affectivity were positively correlated with customer mistreatment. In terms of contextual factors, perceived social support and service climate were negatively related to customer mistreatment, whereas job demands were positively related to customer mistreatment. Moreover, the power distance culture and types of service industries moderated some relationships.
Originality/value
This meta-analytic research, drawing upon the perpetrator predation framework, proposed a new and comprehensive framework to explain why customer mistreatment occurs. It not only promoted the advancement of literature on customer mistreatment but also provided effective and targeted guidance for helping frontline service employees reduce such negative experience.
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Pei Ni Chuah, Dhalini Nyanasegaram, Ke-Xin Yu, Rasny Mohamed Razik, Samer Al-Dhalli, Chin Siang Kue, Khozirah Shaari and Chean Hui Ng
The purpose of this paper is to evaluate the antioxidant activity and toxicity of Clinacanthus nutans leaves from three conventional extraction methods, i.e. maceration, Soxhlet…
Abstract
Purpose
The purpose of this paper is to evaluate the antioxidant activity and toxicity of Clinacanthus nutans leaves from three conventional extraction methods, i.e. maceration, Soxhlet and magnetic stirring.
Design/methodology/approach
Total flavonoid content (TFC) and phenolic content (TPC) were determined using colorimetric method of aluminum chloride and Folin-Ciocalteu (FC) assay, respectively. Antioxidant property of C. nutans was evaluated using 2,2'-diphenyl-1-pierylhydrazyl (DPPH) free radical scavenging assay. Cytotoxic activity of C. nutans against brine shrimp was evaluated based on LC50 (lethality concentration) after 24 h exposure to the plant extract.
Findings
The highest TPC of C. nutans was observed with Soxhlet extraction method (98.87 ± 10.43 mg of gallic acid equivalents (GAE/g) followed by maceration (68.77 ± 2.45 mg of GAE/g) and magnetic stirring (46.75 ± 2.45 mg of GAE/g). Interestingly, remarkable highest TFC was observed with magnetic stirring (568.90 ± 4.85 mg of rutin equivalent (RE)/g) followed by maceration (249.60 ± 2.79 mg of RE/g) and Soxhlet (174.8 ± 1.74 mg of RE/g). On the other hands, the extract obtained using maceration method showed the highest antioxidant activity (IC50: 14.18 mg/mL compared to ascorbic acid 144.36 µg/mL). Cytotoxicity of C. nutans from all extraction methods showed similar LC50 values with maceration (3.81 mg/mL), Soxhlet (2.61 mg/mL) and magnetic stirring (4.56 mg/mL), respectively.
Originality/value
Both phenolic and flavonoids are responsible for the antioxidant activity, of C. nutans extracts. Based on Meyer's toxicity index, all extracts were nontoxic (LC50>1 mg/mL).
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Kun-cheng Zhang, Xin-chang Guo, Shi-zheng Tian, Qi Cui, Mao-chong Shi and Pei-fang Guo
Many experts suggest that the human being explore marine resources and marine new energy sources to alleviate the shortage of land resources and the ecological degradation…
Abstract
Purpose
Many experts suggest that the human being explore marine resources and marine new energy sources to alleviate the shortage of land resources and the ecological degradation. However, island coastal zones are considered to be fragile ecosystems; their geographical location and natural characteristics, their biodiversity and associated ecosystems, and their exposure to diverse land and sea conditions all make them highly vulnerable to environmental changes and human activities. Therefore, it is necessary to achieve the goals of environmental protection and sustainable development on the basis of a comprehensive evaluation and understanding of islands.
Design/methodology/approach
Due to the importance of island groups, this paper conducts evaluation studies on them. Using the Delphi, AHP and TOPSIS methods, this study evaluated quantitatively the comprehensive development level and comprehensive development potential of island groups in terms of resources, natural environment, economy and society. Innovatively using them as two subsystems, the present study combined the coupling coordination model and the obstacle factor calculation method.
Findings
The prospective index of comprehensive development was applied to the Changdao Island Group in Yantai, Shandong Province as an example, and the final evaluation revealed that the comprehensive development prospect of this island group had an upward trend from 2010 to 2017. Future efforts should be made to improve its economic and social conditions and economic development status, apart from promoting its comprehensive development by improving human resources management, increasing the GDP growth rate, and improving fresh water and electricity supply.
Originality/value
This study takes the integrated development level of the island and the integrated development potential of the island as two subsystems, and the innovative application of the coupling coordination degree model is used to calculate the integrated development index of the island to understand the development status of the island area. On the basis of this model, the obstacle factor identification method is designed to identify the main obstacle factors, and on the basis of evaluation and identification, specific measures to ensure the sustainable development of the island area are effectively proposed.
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Xin Feng, Yuehao Liu and Xu Wang
The sudden COVID-19 epidemic in 2019 has frustrated China's overall economy, and the implementation and development of the National Fitness Program has encountered huge obstacles…
Abstract
Purpose
The sudden COVID-19 epidemic in 2019 has frustrated China's overall economy, and the implementation and development of the National Fitness Program has encountered huge obstacles. At a new historical starting point, in order to realize the dream of becoming a powerful country in sports, it is necessary to transform the successful experience gained since the reform and opening up into regular understanding and systematic theories, so as to make a theoretical response to the new contradictions and challenges faced in development and give full play to the National Fitness has comprehensive values and multiple functions in improving people's health, promoting people's all-round development, promoting economic and social development and demonstrating the country's cultural soft power.
Design/methodology/approach
Taking the topic of national fitness as an example, this paper sets out from the three dimensions of knowledge input, knowledge output and knowledge production, using citation analysis, social network analysis, co-word analysis and cluster analysis, to measure the characteristics and knowledge structure of interdisciplinary knowledge exchange.
Findings
China's national fitness is still in the primary development stage, and the strong boost of the national top-level policy is the biggest driving force of its development, driven by the policy together with the settlement of many major events, constantly improving and enriching the wings. The main body of knowledge production on the topic of national fitness is mainly colleges and universities, with low participation of government and enterprises, high degree of cooperation among authors, obvious interdisciplinary characteristics and strong application of research themes.
Originality/value
This study provides a strong theoretical basis for the promotion of the Healthy China strategy. Especially under the influence of COVID-19, this paper can contribute to the comprehensive value and multimodal functions of national fitness in improving the health of people, promoting economic and social development and demonstrating the soft power of national culture.