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1 – 10 of 120Ansheng Zhang, Mingyu Zhang, Jing Wang, Jianjun Zhang, Zhaohua Shang, Yi Liu and Longjie Dai
The purpose of this paper is to study the influence of surface precision on the lubrication state of the roller chain under adequate and rare oil supply conditions, respectively.
Abstract
Purpose
The purpose of this paper is to study the influence of surface precision on the lubrication state of the roller chain under adequate and rare oil supply conditions, respectively.
Design/methodology/approach
The straightness error and roughness error of the pin generatrices were measured and the influence of surface precision on the lubrication behavior under steady state and reciprocating motion was studied through optical interference experiments.
Findings
The lubrication state is strongly influenced by the surface precision of the roller surface both under adequate oil supply and rare oil supply conditions.
Originality/value
In industrial applications, the machining errors of parts cannot be completely eliminated. Studying the influence of the surface precision on the lubrication behavior of pin–bush pairs can provide the experimental basis for the optimal design of the bush roller chains.
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Jianjun Zhang, Qibo Ni, Jing Wang and Feng Guo
Vibration exists widely in all machineries working under high speed. The unpredictability of vibration and the change of the relative surface speed may result in difficulties in…
Abstract
Purpose
Vibration exists widely in all machineries working under high speed. The unpredictability of vibration and the change of the relative surface speed may result in difficulties in the elastohydrodynamic lubrication (EHL) analysis. By far, few studies on EHL relating to vibration have been published. The purpose of the present study is to investigate the effect of the vertical vibrations and the influence of temperature on the thermal EHL contacts.
Design/methodology/approach
The lubricant was assumed to be Newtonian fluid. The time-dependent numerical solutions were achieved instant after instant in each period of the vibration. At each instant, the pressure field was solved with a multi-level technique, the surface deformation was solved with a multi-level multi-integration method and the temperature filed was solved with a finite different scheme through a sweeping progress. The periodic error was checked at each end of the vibration period until the responses of pressure, film thickness and temperature were all periodic functions with the frequency of the roller’s vibrations.
Findings
The results reveal that normal vibration produces little drastic change of pressure, film thickness and temperature in EHL. Under some conditions, the vibrations of the roller can produce transient dimples within the contact conjunction. It is also showed that the lubrication in the same sliding is better than the opposite sliding.
Research limitations/implications
For the unpredictability of vibration, it is not easy to do the experiment to realize a real comparison with numerical results. The reach does not show any verification and consider the effect of non-Newtonian fluid.
Originality/value
The effect of the vertical vibrations on the thermal EHL point contact hast been studied. The effects of both the amplitude and the frequency on the predicted load-carrying capacity, minimum film thickness, center pressure and center temperature and the coefficient of friction were investigated. The role of the thermal effect was given.
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Jiawei Xu, Baofeng Zhang, Jianjun Lu, Yubing Yu, Haidong Chen and Jie Zhou
The importance of the agri-food supply chain in both food production and distribution has made the issue of its development a critical concern. Based on configuration theory and…
Abstract
Purpose
The importance of the agri-food supply chain in both food production and distribution has made the issue of its development a critical concern. Based on configuration theory and congruence theory, this research investigates the complex impact of supply chain concentration on financial growth in agri-food supply chains.
Design/methodology/approach
The cluster analysis and response surface methodology are employed to analyse the data collected from 207 Chinese agri-food companies from 2010 to 2022.
Findings
The results indicate that different combination patterns of supply chain concentration can lead to different levels of financial growth. We discover that congruent supplier and customer concentration is beneficial for companies’ financial growth. This impact is more pronounced when the company is in the agricultural production stage of agri-food supply chains. Post-hoc analysis indicates that there exists an inverted U-shaped relationship between the overall levels of supply chain concentration and financial growth.
Practical implications
Our research uncovers the complex interplay between supply chain base and financial outcomes, thereby revealing significant ramifications for agri-food supply chain managers to optimise their strategies for exceptional financial growth.
Originality/value
This study proposes a combined approach of cluster analysis and response surface analysis for analysing configuration issues in supply chain management.
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Keywords
Abstract
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Menita Liu Cheng, Jianfeng Wu and Jianjun Zhang
The purpose of this paper is to examine corporate political activities (CPA) by migrant entrepreneurs to improve business performance in a host developing country.
Abstract
Purpose
The purpose of this paper is to examine corporate political activities (CPA) by migrant entrepreneurs to improve business performance in a host developing country.
Design/methodology/approach
The authors use a cross‐sectional analysis of 97 Chinese migrant entrepreneurs with business operations in a host developing economy.
Findings
A significant positive relationship was found between formal CPAs and performance.
Research limitations/implications
To further deepen the examination of CPAs, new quantification methodologies have to be applied to properly measure CPA relational strength, investment intensity and diversity.
Practical implications
The results enable migrant entrepreneurs to make a more educated decision on the type of CPAs to pursue and to what intensity.
Social implications
The results could motivate migrant entrepreneurs to adapt rapidly to the host country's formal customs to facilitate socio‐economic adaptation.
Originality/value
This study contributes to literature by examining both formal and informal CPAs, their inter‐relationship and their effects on migrant businesses, which have not been examined previously.
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Abstract
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Mai Thi Thanh Thai and Ekaterina Turkina
The purpose of this paper is to introduce the special issue on “Entrepreneurial migration: characteristics, causes and effects”.
Abstract
Purpose
The purpose of this paper is to introduce the special issue on “Entrepreneurial migration: characteristics, causes and effects”.
Design/methodology/approach
Literature review.
Findings
Studies on immigrant entrepreneurship have become increasingly popular and the importance of social context and social connections has been recognized by scholars. However, research on their effects on immigrant entrepreneurship has been rather limited. This special issue explains the essential steps of the entrepreneurial process by immigrants (i.e. host country choice, entrepreneurial engagement, new venture creation, business network development and corporate political activities) and discusses the effects of immigrant entrepreneurs on their host countries.
Originality/value
The paper presents a review of literature on entrepreneurial migration and social impacts.
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Guangjin Chen, Peng Lu, Zeyan Lin and Na Song
This paper aims to introduce the history and major achievement of the Chinese private enterprise survey (CPES), which is one of the most enduring large-scale nationwide sample…
Abstract
Purpose
This paper aims to introduce the history and major achievement of the Chinese private enterprise survey (CPES), which is one of the most enduring large-scale nationwide sample surveys in China, providing important micro firm-level data for understanding and studying the development of Chinese enterprises and entrepreneurs over the past 26 years.
Design/methodology/approach
The main body of this paper is based on a bibliometric analysis of all literature using CPES until 2017.
Findings
This paper discusses problems that users may encounter during data mining. By doing so, it can assist other researchers to get a better understanding of what has been done (e.g. journals, topics, scholars and institutions) and do their research in a more targeted way.
Research limitations/implications
As members of the survey project team, the authors also take a prospect of the future data design and use, as well as offer some suggestions about how to use the CPES data to improve high-quality development and business environment evaluation in China.
Originality/value
This paper is the first to provide an overall picture of academic papers in China and abroad that have used the CPES data.
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Shaosheng Jin, Haoyang Li and Yao Li
In recent years, fresh produce (fresh vegetables and fruit) has been circulated widely via e-commerce in Chinese large cities in the form of fresh produce portfolios (FPPs). The…
Abstract
Purpose
In recent years, fresh produce (fresh vegetables and fruit) has been circulated widely via e-commerce in Chinese large cities in the form of fresh produce portfolios (FPPs). The purpose of this paper is to analyze the preferences of Chinese consumers for specific FPP attributes.
Design/methodology/approach
A choice experiment approach was used to explore consumer preferences. The authors conducted a means-end-chains evaluation to select the attributes for the choice experiment. The authors used a fractional factorial design and finally obtained 18 choice scenarios. The authors collected 166 effective consumer questionnaires in Beijing.
Findings
The authors found that among the four attributes considered, certification and the diversity of the FPP had significant effects on the willingness to pay (WTP) among consumers. Residents had heterogeneous preferences for FPP diversity and certification, but certification was the major concern when considering fresh produce in the FPP. With regard to the WTP for attributes in the portfolio, the WTP values for “green” and “organic” attributes were high, but the WTP for the diversity of FPPs was low.
Originality/value
This study is the first attempt to explore the preferences of Chinese consumers regarding the attributes of FPP in an e-commerce environment.
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