Kankan Ji, Xingquan Zhang, Shubao Yang, Liping Shi, Shiyi Wang and Yuguo Wu
The purpose of this paper is to evaluate surface integrity of quenched steel 1045 ground drily by the brazed cubic boron nitride (CBN) grinding wheel and the black SiC wheel…
Abstract
Purpose
The purpose of this paper is to evaluate surface integrity of quenched steel 1045 ground drily by the brazed cubic boron nitride (CBN) grinding wheel and the black SiC wheel, respectively. Surface integrity, including surface roughness, sub-surface hardness, residual stresses and surface morphology, was investigated in detail, and the surface quality of samples ground by two grinding wheels was compared.
Design/methodology/approach
In the present work, surface integrity of quenched steel 1045 machined by the CBN grinding wheel and the SiC wheel was investigated systematically. All the specimens were machined with a single pass in the down-cutting mode of dry condition. Surface morphology of the ground specimen was observed by using OLYMPUS BX51M optical microscopy. Surface roughness of seven points was measured by using a surface roughness tester at a cut-off length of 1.8 mm and the measurement traces were perpendicular to the grinding direction. Sub-surface micro-hardness was measured by using HVS-1000 digital micro-hardness tester after the cross-section surface was polished. The residual stress was tested by using X-350A X-ray stress analyzer.
Findings
When the cut depth is increased from 0.01 to 0.07 mm, the steel surface machined by the CBN wheel remains clear grinding mark, lower roughness, higher micro-hardness and higher magnitude of compressive stress and fine microstructure, while the surface machined by the SiC grinding wheel becomes worse with increasing of cut depth. The value of micro-hardness decreases, and the surface roughness increases, and the surface compressive stress turns into tensile stress. Some micro-cracks and voids occur when the sample is processed by the SiC grinding wheel with cut depth 0.07 mm.
Originality/value
In this paper, the specimens of quenched steel 1045 were machined by the CBN grinding wheel and the SiC wheel with various cutting depths. The processing quality resulted from the CBN grinding wheel is better than that resulted from the SiC grinding wheel.
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Guotao Zhang, Baohong Tong, Shubao Yang, Liping Shi and Yanguo Yin
The purpose of this paper was to study the hydrodynamic lubrication of rough bilayer porous bearing to reveal the effect of percolation.
Abstract
Purpose
The purpose of this paper was to study the hydrodynamic lubrication of rough bilayer porous bearing to reveal the effect of percolation.
Design/methodology/approach
The seepage lubrication model of the circular bilayer porous bearing was established in polar coordinates. The digital filtering technique and Darcy’s law were used to simulate the rough surface and the percolation characteristic of the oil bearing, respectively. The influence of the structural parameters on the lubrication performance was analyzed.
Findings
Compared with the ordinary monolayer oil bearing with high porosity, the bilayer bearing can reduce the whole porosity, prevent oil infiltrating into the porous medium and have better lubrication performance. The lubrication performance of bilayer oil bearing is better than that of the single-layer oil bearing which has a higher porosity. With increasing root-mean-square roughness or decreasing surface porosity, the lubrication performance of the bilayer bearing improves. The lower the porosity of the surface layer, the better the lubrication performance.
Originality/value
This research provides a theoretical basis for clarifying the lubrication mechanism and influence the mechanism of the bilayer oil bearing.
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Xiaolin Shi, Jonathon Day, Susan Gordon, Liping Cai and Howard Adler
The purpose of this paper is to examine visitors’ motivations for going to the South Luogu Alley, a famous hutong with an over 700-year history in Beijing, China.
Abstract
Purpose
The purpose of this paper is to examine visitors’ motivations for going to the South Luogu Alley, a famous hutong with an over 700-year history in Beijing, China.
Design/methodology/approach
The study applied a self-administered questionnaire to collect data from visitors on the main street of the South Luogu Alley.
Findings
It was found that most visitors of the hutong are casual tourists pursuing relaxation, including tension release and spending time with friends and family; seeking authenticity is not visitors’ most important motivation.
Research limitations/implications
This study used only one hutong to assess visitors’ motivations in hutong tourism, so the results may not be applicable to all hutongs.
Practical implications
The research on the demographics and different motivations of the South Luogu Alley visitors can be useful to managers of tourism-related organizations.
Social implications
This study shows that tourists with different motivations for visiting a hutong have varying requirements for authenticity. The reconstruction of some historical hutongs is not always perceived as negative, and the influence of Western cultural elements can be seen as positive if they contribute to the sustainable development of the local culture.
Originality/value
The term “hutonger,” which includes casual visitors, entertainment seekers, authenticity seekers and pure escapees, based on these respective motivations, is introduced to describe the specific groups of hutong visitors and contribute to the hutong tourism literature.
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Yin Shi, Liping Ding, Chenchen He, Fan Zhang, Zumeng Zhang and Qiyao Dai
This study aims to analyze those factors affecting the rural resident’s willingness to adopt solar photovoltaic (PV) which is important for accelerating the popularization of…
Abstract
Purpose
This study aims to analyze those factors affecting the rural resident’s willingness to adopt solar photovoltaic (PV) which is important for accelerating the popularization of clean energy in China.
Design/methodology/approach
This study contained a sample of 653 households in 8 provinces/regions by stratified, and random sampling in rural China. Descriptive analysis, exploratory factor analysis and confirmatory factor analysis techniques have been used for analytical purposes.
Findings
The empirical results indicate that financial incentive and social interaction have positive effects on rural residents’ adoption willingness, while village leaders’ engagement can indirectly influence their adoption willingness through social interaction and residents’ cognition.
Research limitations/implications
This study mainly considers external and internal factors but ignores the effect of technical factors. In addition, the samples are just selected from the residents who have adopted solar PV.
Practical implications
This study is expected to be useful for the government, regulators, village leaders, village leaders and other institutions.
Originality/value
This study conducts a systematic analysis and clarifies the relationship between factors (external and internal) and rural residents’ adoption willingness. The village leaders’ engagement is first added to the conceptual model as an external factor, which is very essential in rural residents’ adoption in China.
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Li Gao, Jinnan Song, Jiajuan Liang and Jianxiao Guo
This paper aims to explore the influence of founder shareholders’ resources on the allocation of control rights from the perspective of incomplete contract theory and…
Abstract
Purpose
This paper aims to explore the influence of founder shareholders’ resources on the allocation of control rights from the perspective of incomplete contract theory and resource-based theory.
Design/methodology/approach
This paper analyzes newspaper materials with NVivo11on a case of battle for corporate control in Chinese top-listed company-Vanke Group.
Findings
The research shows that human capital is the key resource and the holding proportion of financial resources directly affects the allocation of control rights. At the same time, social capital is unstable and easily broken. At last, institutional environment also affects the degree between the relationship of founder shareholders’ resources and the allocation of control rights. The influence of founder-shareholder resources on the allocation of control rights follows the path of “crisis – founder-shareholder’s resources – founder’s ability - allocation of control rights.”
Research limitations/implications
This study only selects the financial capital, human capital and social capital of Shi Wang, the founder of Vanke, as the analysis object. The study can expand the types of founder shareholder resources to verify and enrich the conclusions.
Originality/value
The current theoretical research in the literature focuses on the necessity of equity and shareholder’s resources versus the control rights. Some key factors and mechanism on the relationship have not been fully clarified. The results of this paper not only extend the combination research of social network and corporate governance, but also provide enterprise founders with references for making reasonable decisions during control battle.
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Yiling Gao, Chen Wang, Liping Huang, Defa Wang and Zhibin Chen
To help supervisors understand the positions of workers in real-time, provide safety guidance for workers and reduce the occurrence of accidents. This study proposes a real-time…
Abstract
Purpose
To help supervisors understand the positions of workers in real-time, provide safety guidance for workers and reduce the occurrence of accidents. This study proposes a real-time positioning algorithm based on multi-source information coupling, aiming to solve the problem of workers’ autonomous positioning in signal-blind areas.
Design/methodology/approach
The proposed algorithm utilizes the visual SLAM and IMU sensors to perceive the environment, construct three-dimensional images, improve the accuracy of corner point matching, pre-integrate the raw IMU data, and adopt the tightly coupled method to couple the visual and inertial navigation data, thereby establishing a binocular visual SLAM and IMU coupling real-time positioning model.
Findings
The real-time positioning technology based on the coupling of visual SLAM and IMU shows good positioning effect and calculation speed in indoor sites, has good adaptability and accuracy in different building construction scenarios, and the positioning error can be controlled within 3%.
Originality/value
The successful construction of the real-time positioning method effectively alleviates the problem of inaccurate positioning caused by signal blind areas in the existing positioning management system, helps protect the lives and safety of construction site workers and improves the management efficiency of construction site supervisors.
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Yu Yuan, Jia Liao and Liping Zheng
This study empirically investigates the impact of directors' and officers' liability insurance on corporate environmental investment.
Abstract
Purpose
This study empirically investigates the impact of directors' and officers' liability insurance on corporate environmental investment.
Design/methodology/approach
This paper takes A-share listed firms in the most polluting industries from 2013 to 2019 as the research sample. The authors perform multiple regression analysis to examine the research question, and other approaches such as PSM and Heckman two-stage model are applied to test the robustness of the main results.
Findings
The authors find that D&O insurance insured firms significantly decrease the level of corporate environmental investment. The results keep consistent after alleviating potential endogenous concerns. Further analysis shows that the negative association between D&O insurance and environmental investment is more pronounced in firms facing greater environmental pressure and stronger market supervision, and firms located in regions with a rich legal environment.
Research limitations/implications
This research extends the literature on the antecedents of corporate environmental investment and the consequences of D&O insurance.
Practical implications
The study may deepen people's understanding of D&O insurance and inform them of its negative effects. This research sheds light on the potential factor resulting in a relatively low level of corporate environmental investment in China, which has an important policy implication for government to carry out some regulations to make a difference.
Originality/value
Against the backdrop that more importance has been attached to environmental protection globally, this paper is the first study to examine the impact of D&O insurance on corporate environmental investment in the context of the transitional and emerging market-China.
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John Sneed and Donald Ace Morgan
From a roundup of recent literature on the effectiveness of the current accounting curriculum in the USA, identifies a consensus that additional education is needed to better…
Abstract
From a roundup of recent literature on the effectiveness of the current accounting curriculum in the USA, identifies a consensus that additional education is needed to better prepare students for their careers in the accounting profession and seeks to determine which areas need to be addressed if substantial improvement is to be achieved within the curriculum; analyses data collected from the results of students’ tests undertaken over three consecutive semesters at a US Midwest university to assess students’ quantitative, verbal and problem‐solving skills, and finds that performance in the latter two areas was consistently less impressive than in the former. As each of these areas is seen as important to accounting careers, suggests that more attention should be paid to communication and problem‐solving skills as part of the curriculum, although not at the expense of technical skills; tabulates and briefly discusses a number of other findings from the research, for example with regard to gender differences across the skill areas.
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This paper aims to provide top-level design and basic platform for intelligent application in China high-speed railway.
Abstract
Purpose
This paper aims to provide top-level design and basic platform for intelligent application in China high-speed railway.
Design/methodology/approach
Based on the analysis for the future development trends of world railway, combined with the actual development needs in China high-speed railway, The definition and scientific connotation of intelligent high-speed railway (IHSR) are given at first, and then the system architecture of IHSR are outlined, including 1 basic platform, 3 business sectors, 10 business fields, and 18 innovative applications. At last, a basic platform with cloud edge integration for IHSR is designed.
Findings
The rationality, feasibility and implementability of the system architecture of IHSR have been verified on and applied to the Beijing–Zhangjiakou high-speed railway, providing important support for the construction and operation of the world’s first IHSR.
Originality/value
This paper systematically gives the definition and connotation of the IHSR and put forward the system architecture of IHSR for first time. It will play the most important role in the design, construction and operation of IHSR.
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This paper aims to establish the mathematical models for the water-lubricated thrust bearing with groove texture considering turbulence and cavitation and numerically analyze the…
Abstract
Purpose
This paper aims to establish the mathematical models for the water-lubricated thrust bearing with groove texture considering turbulence and cavitation and numerically analyze the influence of rotary speed, texture depth, groove number and groove width on the static performance of the bearing.
Design/methodology/approach
The turbulent Reynolds equation and the Jakobsson–Floberg–Olsson cavitation model are adopted for the analysis. The Payvar–Salant algorithm and Finite difference schemes are used to discretize the governing equations. To illustrate the influence of turbulence, the performance of the bearing predicted by the turbulent and laminar models are compared.
Findings
According to the results, the load capacity and the friction force calculated by the turbulent model are greater than those obtained by laminar model, and the deviation between them gradually increases with the increased rotary speed. So, the turbulent effect should be fully considered for high-speed water-lubricated bearing with surface texture. There exists a peak value for the load capacity of the water-lubricated thrust bearing in respect to the texture depth, the number of grooves and the groove width ratio, while the friction force varies slowly with those parameters. Well-designed groove texture can improve the performance of the water-lubricated thrust bearing.
Originality/value
This paper proposes a mathematical model considering turbulent and cavitation effect for water-lubricated thrust bearing with surface texture. This model can be complementary to conventional laminar model which is used to analyze the performance of textured bearing at low rotary speed.