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1 – 10 of 103Biao Li, Jun Sun, Hu Wang and Xiao Zhang
Under the action of many factors, the shaft of the shaft-journal bearing system inevitably moves along the axis direction at work, which will lead to the axial movement of journal…
Abstract
Purpose
Under the action of many factors, the shaft of the shaft-journal bearing system inevitably moves along the axis direction at work, which will lead to the axial movement of journal in the bearing. However, at present, only the dynamic and squeezing effects caused by the relative rotation and squeezing motion between the journal and the bearing surfaces are considered in the lubrication analysis of misaligned journal bearing and the axial movement of journal in the actual use of bearing is not considered. The purpose of this paper is to analyze the lubrication of journal bearing considering the axial movement of journal.
Design/methodology/approach
Taking the shaft-journal bearing system as the research object, a hydrodynamic lubrication model of journal bearing is established considering the axial movement and misalignment of journal. The finite difference method is used to solve the Reynolds equation for the lubrication analysis.
Findings
The axial movement of journal has a significant influence on the lubrication characteristics of misaligned journal bearing. The larger the misalignment angles of journal or the eccentricity of bearing, the greater the influence of the axial movement of journal on the lubrication performance of bearing. The lower the speed of bearing or the smaller the clearance of bearing, the more significant the influence of the axial movement of journal on the lubrication performance of bearing is.
Originality/value
The influence of the axial movement of journal on the lubrication performance of journal bearing is studied under different misalignment angles of journal, working conditions and clearances of bearing. The results of this paper are helpful to the design and research of the lubrication performance of journal bearing.
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This paper aims to investigate the evolution law of surface characteristic of corroded cold-formed thin-walled steel in industrial environments.
Abstract
Purpose
This paper aims to investigate the evolution law of surface characteristic of corroded cold-formed thin-walled steel in industrial environments.
Design/methodology/approach
Five test specimens sourced from cold-formed thin-walled C-shaped steel that have been in service for three years in actual industrial environments were subjected to surface characteristic test. The surface characteristic of corroded hot-rolled steel and cold-formed steel were compared and analyzed. The relationship between the surface morphology parameters and the average corrosion depth was established.
Findings
The evolution law of the surface morphology of corroded cold-formed thin-walled steel and corroded hot-rolled steel was similar. The frequency histogram of corrosion depth was mainly single peak with high values on the middle and low values on both sides. The corrosion depth conformed to the normal distribution. The roughness average height and the root mean square of surface height gradually increased linearly with increasing the average corrosion depth.
Originality/value
The reduction in the standard deviation of corrosion depth, the maximum corrosion depth, the roughness average height and the root mean square of surface height of the cold-formed thin-walled steel was smaller than those of the hot-rolled steel.
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Min Li, Wenyuan Huang, Chunyang Zhang and Zhengxi Yang
The purpose of this paper is to draw on triadic reciprocal determinism and social exchange theory to examine how “induced-type” and “compulsory-type” union participation influence…
Abstract
Purpose
The purpose of this paper is to draw on triadic reciprocal determinism and social exchange theory to examine how “induced-type” and “compulsory-type” union participation influence union commitment and job involvement, and how union participation in the west differs from that in China. It also examines whether the role of both organizational justice and employee participation climate (EPC) functions in the Chinese context.
Design/methodology/approach
Cross-sectional data are collected from 694 employees in 46 non-publicly owned enterprises, both Chinese and foreign, in the Pearl River Delta region of China. A multi-level moderated mediation test is used to examine the model of this research.
Findings
Union participation is positively related to organizational justice, union commitment and job involvement. In addition, organizational justice acts as the mediator among union participation, union commitment and job involvement. Specifically, the mediating role of organizational justice between union participation and union commitment, and between union participation and job involvement, is stronger in high-EPC contexts than low-EPC contexts.
Originality/value
Instead of examining the impacts of attitudes on union participation, as per most studies in the western context, this research examines the impacts of union participation in the Chinese context on attitudes, including union commitment and job involvement. It also reveals the role of both organizational justice and EPC in the process through which union participation influences union commitment and job involvement.
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Hong-Yan Liu, Ji-Huan He and Zheng-Biao Li
Academic and industrial researches on nanoscale flows and heat transfers are an area of increasing global interest, where fascinating phenomena are always observed, e.g. admirable…
Abstract
Purpose
Academic and industrial researches on nanoscale flows and heat transfers are an area of increasing global interest, where fascinating phenomena are always observed, e.g. admirable water or air permeation and remarkable thermal conductivity. The purpose of this paper is to reveal the phenomena by the fractional calculus.
Design/methodology/approach
This paper begins with the continuum assumption in conventional theories, and then the fractional Gauss’ divergence theorems are used to derive fractional differential equations in fractal media. Fractional derivatives are introduced heuristically by the variational iteration method, and fractal derivatives are explained geometrically. Some effective analytical approaches to fractional differential equations, e.g. the variational iteration method, the homotopy perturbation method and the fractional complex transform, are outlined and the main solution processes are given.
Findings
Heat conduction in silk cocoon and ground water flow are modeled by the local fractional calculus, the solutions can explain well experimental observations.
Originality/value
Particular attention is paid throughout the paper to giving an intuitive grasp for fractional calculus. Most cited references are within last five years, catching the most frontier of the research. Some ideas on this review paper are first appeared.
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Zheng-Biao Li and Wei-Hong Zhu
– The purpose of this paper is to suggest a new analytical technique called the fractional series expansion method for solving linear fractional differential equations (FDEs).
Abstract
Purpose
The purpose of this paper is to suggest a new analytical technique called the fractional series expansion method for solving linear fractional differential equations (FDEs).
Design/methodology/approach
This method is based on the idea of Kantorovich method, convergent series, and the modified Riemann-Liouville derivative.
Findings
This work suggests a new analytical technique. The FDEs are described in Jumarie’s sense.
Originality/value
It finds a new method for solving linear FDEs. The solution procedure is elucidated by two examples.
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Hong Lu, Wenquan Ling, Yuju Wu and Yi Liu
The purpose of this paper is to explore the fundamental content and structure of destructive leadership within the Chinese cultural context, through surveys of employees in…
Abstract
Purpose
The purpose of this paper is to explore the fundamental content and structure of destructive leadership within the Chinese cultural context, through surveys of employees in Chinese organizations.
Design/methodology/approach
Methodologies such as documentary analysis, interview and survey were used in the study, and surveys were conducted on over 1,300 employees from Beijing, Shanghai and other cities in Guangdong and Zhejiang provinces. Then the content and structure of destructive leadership perceived by Chinese employees were examined using multiple statistical techniques including EFA (exploratory factor analysis) and CFA (confirmatory factor analysis).
Findings
The results of the survey showed that destructive leadership in Chinese organizations consists of four factors: corruption, excoriation of subordinates, abuse of subordinates and the loss of professional morality. The authors then compared the structure with relevant Western research findings and revealed their similarities and differences.
Practical implications
The structure of Chinese destructive leadership not only reflects the characteristics of Chinese culture, but also reflects the characteristics of current Chinese organizational management, which have practical implications for identifying management problems in Chinese organizations and improving workplace leadership behavior.
Originality/value
This is the first paper of its kind in mainland China to empirically explore the theoretical model of destructive leadership within the context of Chinese culture, which will facilitate future research by offering a theoretical basis and research instrument.
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Family farms are seen as a powerful force for rural development, and they are gaining more and more research attention. This study aims to explore the relationship between the…
Abstract
Purpose
Family farms are seen as a powerful force for rural development, and they are gaining more and more research attention. This study aims to explore the relationship between the social networks of family farms and the dual innovation of the family farm business model from the perspective of entrepreneurial orientation.
Design/methodology/approach
Using a questionnaire survey of 169 family farms in Qingdao, China, descriptive and inferential statistics were used to analyze the data collected. The study hypothesis was tested using inferential tests (regression analysis).
Findings
The study results show that innovative, efficiency- and novelty-based business models facilitated by social networks have a favorable and significant impact on the performance of family farms. Furthermore, the relationship between social networks and new business model creation is positively influenced by an entrepreneurial orientation.
Originality/value
This study is distinctive in that it examines the mechanisms underlying family farm growth from an entrepreneurial standpoint, classifying family farm social networks for the first time into social, market and governmental categories and looking at their impact on the creation of new business models. In addition, it looks into the relationship between the innovation and social network aspect of the family farm business model from an entrepreneurial perspective, offering fresh insight into this connection. It also examines the family farm business model’s connection to innovation and social networks from an entrepreneurial standpoint, providing new insight into this relationship.
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Jianpeng Wu, Biao Ma, Heyan Li and Chengnan Ma
The purpose of this paper is to study friction and wear properties of three types of steels against paper-based friction disc, including 65Mn, 20#steel and 30CrAl, so as to obtain…
Abstract
Purpose
The purpose of this paper is to study friction and wear properties of three types of steels against paper-based friction disc, including 65Mn, 20#steel and 30CrAl, so as to obtain the appropriate working conditions for different friction materials in the transmission system.
Design/methodology/approach
Based on actual working conditions, pin-on-disc tests are conducted on a universal material tester. The two evaluation indexes, including average friction coefficient and variation coefficient, are introduced to analyze the different friction properties among three types of steel. Furthermore, the temperature-dependent wear pattern and wear depth are subsequently studied.
Findings
The results show that 65Mn is more suitable for working under heavy load and low velocity, but 30CrAl and 20#steel are suitable for working under light load and high velocity. Moreover, wear primarily occurs on paper-based material and peaks at about 325.
Practical implications
This research of different materials and friction property for friction pairs is helpful to improve the performance and prolong the service life of transmission systems.
Originality/value
Suitable working conditions of different friction materials are obtained, and the correlation between wear and decomposition in high temperature is verified.
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Xiaoping Zhuang, Li Lin, Rongteng Zhang, Jun (Justin) Li and Biao He
This study attempts to explore major attributes of food delivery applications in consideration of their impacts upon perceived service quality, satisfaction and usage intention. A…
Abstract
Purpose
This study attempts to explore major attributes of food delivery applications in consideration of their impacts upon perceived service quality, satisfaction and usage intention. A multi-group analysis is performed to examine the hypothesized relationships in the structural models for the millennials and non-millennials.
Design/methodology/approach
The data was collected from 311 food delivery application users. The structural equation model (SEM) was designed to examine the interrelationships among variables.
Findings
The findings indicate that five salient dimensions that include ease of use, facility aesthetics, trustworthiness, value for money and product portfolio have a significant impact on overall service quality. Results further demonstrate that differences in generational difference partially moderate the relationship between each attribute of the food delivery application service quality as well as overall service quality.
Originality/value
The rapid evolution of the Internet and mobile communication has resulted in the proliferation of food delivery applications in China. However, to the best of our knowledge, only a few studies have focused on measuring the key dimension of service quality of food delivery applications.
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