Jianhua Ding, Jianhua Fang, Boshui Chen, Nan Zhang, Xingyu Fan and Zhe Zheng
This paper aims to understand the influences of tris (2-hydroxyethyl) isocyanurate oleate and oleic acid tris (2-hydroxyethyl) isocyanurate phosphate ester on biodegradability and…
Abstract
Purpose
This paper aims to understand the influences of tris (2-hydroxyethyl) isocyanurate oleate and oleic acid tris (2-hydroxyethyl) isocyanurate phosphate ester on biodegradability and tribological performances of mineral lubricating oil.
Design/methodology/approach
Tris (2-hydroxyethyl) isocyanurate oleate and oleic acid tris (2-hydroxyethyl) isocyanurate phosphate ester were prepared and characterized by Fourier transform infrared spectrometer. The biodegradability and tribological properties of neat oil and its formulations were studied on a tester for fast evaluating biodegradability of lubricants and a four-ball tester, respectively. The worn surfaces were investigated by scanning electron microscope and X-ray photoelectron spectroscope.
Findings
Tris (2-hydroxyethyl) isocyanurate oleate and oleic acid tris (2-hydroxyethyl) isocyanurate phosphate ester both improved markedly the biodegradability, the anti-wear properties, friction-reducing properties and extreme pressure properties of base oil. The effect of oleic acid tris (2-hydroxyethyl) isocyanurate phosphate ester was better than tris (2-hydroxyethyl) isocyanurate oleate. The improvement of tribological performances was mainly ascribed to the formation of a complicated boundary lubrication film of tris (2-hydroxyethyl) isocyanurate oleate and oleic acid tris (2-hydroxyethyl) isocyanurate phosphate ester on the friction surfaces.
Originality/value
This paper has indicated that tris (2-hydroxyethyl) isocyanurate oleate and oleic acid tris (2-hydroxyethyl) isocyanurate phosphate ester effectively improve the biodegradability and tribological performances of mineral lubricating oil. Promoting biodegradation of mineral lubricant by additives is very significant for the development of petroleum-based biodegradable lubricants. These two additives not merely improve the tribological performances; more importantly, they improve the ecological performances.
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Zeqi Jiang, Jianhua Fang, Fei Chen, Boshui Chen and Kecheng Gu
This paper aims at understanding tribological properties of lubricating oils doped with zinc dithiophosphate(ZDDP) with and without electromagnetic field impact.
Abstract
Purpose
This paper aims at understanding tribological properties of lubricating oils doped with zinc dithiophosphate(ZDDP) with and without electromagnetic field impact.
Design/methodology/approach
The friction and wear properties of the oils formulated with zinc butyloctyl dithiophosphate (T202) or zinc dioctyl dithiophosphate (T203) under electromagnetic field or nonelectromagnetic field were evaluated on a modified four-ball tribotester. The characteristics of the worn surfaces obtained from electromagnetic or nonelectromagnetic field conditions were analyzed by scanning electronic microscopy, energy dispersive spectrometer and X-ray photoelectron spectroscopy. This paper focuses on understanding influence of electromagnetic field on lubrication effect of the ZDDP-formulated oils.
Findings
The electromagnetic field could effectively facilitate anti-wear and friction-reducing properties of the oils doped with T202 or T203 as compared to those without electromagnetism affection, and the T203-doped oils were more susceptible to the electromagnetic field. The improvement of anti-wear and friction-reducing abilities of the tested oils were mainly attributed to the promoted tribochemical reactions and the modification of the worn surfaces (forming Zn-Fe solid solution) induced by the electromagnetic field.
Originality/value
This paper has revealed that tribological performances of ZDDP-doped oils could be improved by the electromagnetic field and discussed its lubrication mechanisms. Investigating tribological properties of additives from the viewpoint of electromagnetics is a new attempt, which has significance not only for the choose and designing of additives in electromagnetic condition but also for development of tribological theories and practices.
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Boshui Chen, Weijiu Huang and Jianhua Fang
The purpose of this paper is to understand the impacts of oleoyl glycine on biodegradation, friction and wear performances of a mineral lubricating oil.
Abstract
Purpose
The purpose of this paper is to understand the impacts of oleoyl glycine on biodegradation, friction and wear performances of a mineral lubricating oil.
Design/methodology/approach
The biodegradabilities of a neat oil and its formulations with oleoyl glycine were evaluated on a biodegradation tester and the microbial characters in the biodegradation sewage observed through a microscope. Also, the friction and wear performances of neat oil and the formulated oil were determined on a four‐ball tribometer. The morphologies and tribochemical features of the worn surfaces were analyzed by scanning electron microscopy and X‐ray photoelectron spectroscopy.
Findings
Oleoyl glycine markedly enhanced biodegradation of unreadily biodegradable mineral oil and effectively improved its anti‐wear and friction‐reducing abilities. The enhancement of biodegradability of the mineral oil was preliminarily ascribed to the increment of microbial populations in the biodegradation processes, while the improvement of anti‐wear and friction‐reducing abilities was mainly attributed to the formation of a boundary adsorption film of oleoyl glycine on the friction surfaces.
Originality/value
Oleoyl glycine is a biodegradable and low eco‐toxic compound. The authors' work has shown that oleoyl glycine is effective in improving biodegradability and tribological performances of mineral lubricants. Enhancing biodegradability of petroleum‐based lubricants by additives is a new attempt. The paper has significance for improving ecological and tribological performances of mineral lubricants, even for developing petroleum‐based biodegradable lubricants.
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The purpose of this paper is to employ a Yin-Yang harmony perspective to propose a novel circled 5C model to understand the unique harmonizing process of how conflicts are…
Abstract
Purpose
The purpose of this paper is to employ a Yin-Yang harmony perspective to propose a novel circled 5C model to understand the unique harmonizing process of how conflicts are resolved in China. Despite increasing research on labor conflicts in Chinese manufacturing, Western theories still can not explain how Chinese culture influences conflict management.
Design/methodology/approach
The authors investigate a large manufacturer where a severe labor strike happened in South China. A mixed-methods research design is adopted. The scale of Chinese harmony and analysis of variance are used to identify the underlying unharmonious factors triggering the labor strike. The grounding theory approach (a case study) was adopted to further examine the proposed 5C model.
Findings
“Harmony with corporate system”, “Harmony between departments” and “Harmony with firm leader” were found to arouse employee grievances the most. Differences in age, gender, marital status, educational level, tenure and position were discovered to affect workers’ perceptions of workplace harmony. The proposed 5C model was supported.
Practical implications
As a lesson in handling escalating labor conflicts, this study allows foreign investors to better understand how to cope with relevant labor strife issues in China. In addition, this project integrates research with consultancy service, which can be seen as an exciting step forward in bridging academics and practitioners.
Originality/value
Based on Yin-Yang harmony thinking, this study suggests an integrative, context-specific concern – concern for harmony for China to transcend the Western dual-concern model regarding the choice of coping with conflicts. The paper constructs a novel circled 5C model of the Chinese harmonizing process (conflict, clash, communication, comprise and consensus), which characterizes the dynamic, contingent and art-oriented nature of Chinese conflict management.
Hangjun Zhang, Jinhui Fang, Jianhua Wei, Huan Yu and Qiang Zhang
This paper aims to present an adaptive sliding mode control (ASMC) for tunnel boring machine cutterhead telescopic system with uncertainties to achieve a high-precision trajectory…
Abstract
Purpose
This paper aims to present an adaptive sliding mode control (ASMC) for tunnel boring machine cutterhead telescopic system with uncertainties to achieve a high-precision trajectory in complex strata. This method could be applied to solve the problems caused by linear and nonlinear model uncertainties.
Design/methodology/approach
First, an integral-type sliding surface is defined to reduce the static tracking error. Second, a projection type adaptation law is designed to approximate the linear and nonlinear redefined parameters of the electrohydraulic system. Third, a nonlinear robust term with a continuous approximation function is presented for handling load force uncertainty and reducing sliding mode chattering. Moreover, Lyapunov theory is applied to guarantee the stability of the closed-loop system. Finally, the effectiveness of the proposed controller is proved by comparative experiments on a scaled test rig.
Findings
The linear and nonlinear model uncertainties lead to large variations in the dynamics of the mechanism and the tracking error. To achieve precise position tracking, an adaptation law was integrated into the sliding mode control which compensated for model uncertainties. Besides, the inherent sliding mode chattering was reduced by a continuous approximation function, while load force uncertainty was solved by a nonlinear robust feedback. Therefore, a novel ASMC for tunnel boring machine cutterhead telescopic system with uncertainties can improve its tracking precision and reduce the sliding mode chattering.
Originality/value
To the best of the authors’ knowledge, the ASMC is proposed for the first time to control the tunnel boring machine cutterhead telescopic system with uncertainties. The presented control is effective not only in control accuracy but also in parameter uncertainty.
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Shixin Zhang, Jianhua Shan, Fuchun Sun, Bin Fang and Yiyong Yang
The purpose of this paper is to present a novel tactile sensor and a visual-tactile recognition framework to reduce the uncertainty of the visual recognition of transparent…
Abstract
Purpose
The purpose of this paper is to present a novel tactile sensor and a visual-tactile recognition framework to reduce the uncertainty of the visual recognition of transparent objects.
Design/methodology/approach
A multitask learning model is used to recognize intuitive appearance attributes except texture in the visual mode. Tactile mode adopts a novel vision-based tactile sensor via the level-regional feature extraction network (LRFE-Net) recognition framework to acquire high-resolution texture information and temperature information. Finally, the attribute results of the two modes are integrated based on integration rules.
Findings
The recognition accuracy of attributes, such as style, handle, transparency and temperature, is near 100%, and the texture recognition accuracy is 98.75%. The experimental results demonstrate that the proposed framework with a vision-based tactile sensor can improve attribute recognition.
Originality/value
Transparency and visual differences make the texture of transparent glass hard to recognize. Vision-based tactile sensors can improve the texture recognition effect and acquire additional attributes. Integrating visual and tactile information is beneficial to acquiring complete attribute features.
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Wen Gao, Jianhua Wei, Yu Li, Dongxue Wang and Lele Fang
This study aimed to investigate positive associations between three main motivations (social interaction, information and entertainment) for the use of social network sites (SNSs…
Abstract
Purpose
This study aimed to investigate positive associations between three main motivations (social interaction, information and entertainment) for the use of social network sites (SNSs) and users' well-being, as well as the multiple mediating effects of perceived social support, positive and honest self-presentation.
Design/methodology/approach
A sample of 759 active users of SNSs (WeChat Moments, Qzone and Weibo) aged 14–43 years was measured with online questionnaires. Correlation analysis and structural equation modeling were implemented to examine the corresponding hypotheses.
Findings
The results showed the overall intensity of motivations was positively associated with users' well-being; perceived social support and positive self-presentation played intermediary roles and honest self-presentation and perceived social support had a chain mediation effect. However, the motivations of social interaction, information and entertainment indirectly affected users' well-being through three different mediation paths.
Originality/value
Although some studies have investigated the effects of motivations (including social interaction, information and entertainment) for SNS use on users' well-being, there has not been a consistent conclusion. The findings may shed light on the motivations for SNS use and how they may affect people's well-being in the digital era, thereby promoting their healthy use of SNSs as well as improved interface design and user management of SNSs.
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Md. Helal Miah, Jianhua Zhang and Gurmail Singh Malhi
“V-bending” is the most commonly used bending process in which the sheet metal is pressed into a “V-shaped” die using a “V-shaped” punch to form a required angular bend. When the…
Abstract
Purpose
“V-bending” is the most commonly used bending process in which the sheet metal is pressed into a “V-shaped” die using a “V-shaped” punch to form a required angular bend. When the punch is removed after the operation, because of elastic recovery, the bent angle varies. This shape discrepancy is known as spring back which causes problems in the assembly of the component in the modern aerospace industry. Regarding the optimization of spring-back accuracy, this research will illustrate the laws of the transition area (TA) of the nondeformation area (NDA) during the 90° “V-shape” bending process.
Design/methodology/approach
According to the traditional “V-bending” process to optimize the spring-back accuracy, the bent sheets are divided into deformation area (DA) and NDA. For this reason, the traditional “V-bending” process may prolong error to optimize the spring-back accuracy because NDA has a certain amount of deformation, which the researcher always avoids. Firstly, bent sheets are divided into three parts in this research: DA, TA and NDA to avoid the distortion error in TA that are not considered in the NDA in traditional theory. Then, the stress and strain in the DA and TA were discussed during theoretical derivation and some hypotheses were proposed. In this research, the interval, position and distortion degree of the TA of the bending sheet are used by finite element analysis. Finally, V-shape bending tests for aluminum alloy at room temperature are used and labeled all the work pieces' TAs to realize the deformation amount in the TA.
Findings
The bending radius does not affect the range of the TA, it only changes the position of TA in the bending sheet. It is evident that the laws of TA were explored in the width direction and gradually changed from the inner layer to the outer layer based on the ratio of width and thickness of the bending plate/sheet.
Originality/value
In the modern aerospace industry, aircraft manufacturing technology must maintain high accuracy. This research has practical value in the 90° “V-shape” bending of metal sheets and the development of its spring-back accuracy.
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Dandan Wen, Jianhua Zhang, Fredrick Ahenkora Boamah and Yilin Liu
Continuous knowledge contribution behaviors (CKCB) are critical for the healthy development of online medical communities (OMCs). However, it is unclear that if and how…
Abstract
Purpose
Continuous knowledge contribution behaviors (CKCB) are critical for the healthy development of online medical communities (OMCs). However, it is unclear that if and how contributors' prior actions and the responses they received from the community influence the nature of their future contributions. Drawing upon the Information Systems Continuance theory and Service Feedback theory, the purpose of the study is to examine the impact of knowledge contribution performance (KCP) on doctors' CKCB. Evaluation of social motivation, financial incentive and the moderating influence of expertise level (EL) provided further insight into the pathways that motivate various forms of CKCB.
Design/methodology/approach
In order to better understand the CKCB of physicians in OMCs, the authors divided it into two categories: A_CKCB (active CKCB) and P_CKCB (passive CKCB). Information Systems Continuance theory and Service Feedback theory are adapted and integrated with empirical findings from previous research on OMCs to develop a model of CKCB. This study used ordinary least squares (OLS) regression to test hypotheses in the preexisting research model based on data collected from a Chinese OMC platform.
Findings
The results show that KCP helps develop several facets of CKCB. According to the findings, doctors' CKCB improved dramatically after receiving feedback from A_CKCB and P_CKCB, but feedback from peers did not promote CKCB. This study found that financial rewards only have a significant positive effect on P_CKCB, and that the level of expertise has a negative effect on the effect. The findings also demonstrated that doctors' level of expertise moderates the relationship between fA_CKCB (a comprehensive evaluation of doctors' A_CKCB) and A_CKCB.
Research limitations/implications
Future studies should look at the role of self-efficacy as a mediator and attitudes as a moderator in the link between KCP and various forms of CKCB. This will help authors figure out how important KCP is for physicians' CKCB. And future research should use more than one way to gather data to prove the above roles.
Practical implications
This study makes a significant contribution to understanding the association between CKCB and KCP by highlighting the significance of distinguishing between the various forms of CKCB and their underlying causes.
Originality/value
This research has advanced both the theory and practice of OMCs' user management by illuminating the central role of KCP in this context.
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Jianhua Zhang, Jiake Li, Sajjad Alam, Fredrick Ahenkora Boamah and Dandan Wen
This study examines the relationship between higher education improvement and tacit knowledge importance. In this context, the scarcity of empirical and theoretical studies on…
Abstract
Purpose
This study examines the relationship between higher education improvement and tacit knowledge importance. In this context, the scarcity of empirical and theoretical studies on acquiring tacit knowledge to enhance academic performance in higher education suggests that this research area holds significant importance for experts and policymakers. Consequently, this study aims to explore the factors that influence academic research performance at Chinese universities by acquiring tacit knowledge.
Design/methodology/approach
To achieve the study aims, the current approach utilizes the research technique based on the socialization, externalization, internalization and combination (SECI) model and knowledge management (KM) theory. To analyze the study objective, the authors collected data from post-graduate students at Chinese universities and analyzed it using structural equation modeling (SEM) to test the model and hypotheses.
Findings
The results indicated that social interaction, internalization and self-motivation have a positive impact on academic research performance through the acquisition of tacit knowledge. Furthermore, the findings suggest that academic researchers can acquire more knowledge through social interaction than self-motivation, thereby advancing research progress.
Originality/value
This study addresses the critical issues surrounding the acquisition of tacit knowledge and presents a comprehensive framework and achievements that can contribute to achieving exceptional academic performance.