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1 – 10 of 22Ao Zhang, Jian Zhang, Mingjun Zhang, Junyi Liu and Ping Peng
This paper aims to investigate the effect and mechanism of O atom single doping, Ce and O atoms co-doping on the interfacial microscopic behavior of brazed Ni-Cr/diamond.
Abstract
Purpose
This paper aims to investigate the effect and mechanism of O atom single doping, Ce and O atoms co-doping on the interfacial microscopic behavior of brazed Ni-Cr/diamond.
Design/methodology/approach
Using first-principles calculations, the embedding energy, work of separation, interfacial energy and electronic structures of Ni-Cr-O/diamond and Ni-Cr-O-Ce/diamond interface models were calculated. Then, the effect of Ce and O co-doping was experimentally verified through brazed diamond with CeO2-added Ni-Cr filler alloy.
Findings
The results show that O single-doping reduces the interfacial bonding strength between Ni-Cr filler alloy and diamond but enhances its interfacial stability to some extent. However, the Ce and O co-doping simultaneously enhances the interfacial bonding strength and stability between Ni-Cr filler alloy and diamond. The in-situ formed Ce-O oxide at interface impedes the direct contact between diamond and Ni-Cr filler alloy, which weakens the catalytic effect of Ni element on diamond graphitization. It is experimentally found that the fine rod-shaped Cr3C2 and Cr7C3 carbides are generated on diamond surface brazed with CeO2-added Ni-Cr filler alloy. After grinding, the brazed diamond grits, brazed with CeO2-added Ni-Cr filler alloy, present few fracture and the percentage of intact diamond reaches 67.8%. Compared to pure Ni-Cr filler alloy, the brazed diamond with CeO2-added Ni-Cr filler alloy exhibit the better wear resistance and the slighter thermal damage.
Originality/value
Using first-principles calculations, the effect of Ce and O atoms co-doping on the brazed diamond with Ni-Cr filler alloy is investigated, and the calculation results are verified experimentally. Through the first-principles calculations, the interface behavior and reaction mechanism between diamond and filler alloy can be well disclosed, and the composition of filler alloy can be optimized, which will be beneficial for synergistically realizing the enhanced interface bonding and reduced thermal damage of brazed diamond.
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Keywords
Mingjun Zhang, Weimin Tao, William Fisher and Tzyh‐Jong Tarn
For semiconductor and gene‐chip microarray fabrication, robots are widely used to handle workpieces. It is critical that robots can calibrate themselves regularly and estimate…
Abstract
Purpose
For semiconductor and gene‐chip microarray fabrication, robots are widely used to handle workpieces. It is critical that robots can calibrate themselves regularly and estimate workpiece pose automatically. This paper proposes an industrial method for automatic robot calibration and workpiece pose estimation.
Design/methodology/approach
The methods have been implemented using an air‐pressure sensor and a laser sensor.
Findings
Experimental results conducted in an industrial manufacturing environment show efficiency of the methods.
Originality/value
The contribution of this paper consists of an industrial solution to automatic robot calibration and workpiece pose estimation for automatic semiconductor and gene‐chip microarray fabrication.
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WeiMin Tao, MingJun Zhang, Ou Ma and XiaoPing Yun
The purpose of this paper is to investigate the vibration suppression of industrial track robot and propose a practical solution.
Abstract
Purpose
The purpose of this paper is to investigate the vibration suppression of industrial track robot and propose a practical solution.
Design/methodology/approach
Root‐cause analysis through dynamic modeling, and vibration suppression using the acceleration smoother.
Findings
The vibration is due to insufficient damping based on the model analysis. The solution achieved significant performance improvement without redesign of robot hardware and controller.
Research limitations/implications
The design of the proposed acceleration smoother is still empirical based, which is unable to achieve optimal design.
Practical implications
This solution is very easy to implement. It is robust, reliable and is able to generate consistent results.
Originality/value
A very practical industrial solution, especially useful for upgrading the existing systems in the field without redesign the hardware and controller.
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Keywords
Douqing Zhang, Mingjun Li, Xiang Ji, Jie Wu and Yilun Dong
The purpose of this paper is to generate quantitative managerial insights for the improvement of the energy-saving potential and the coordinated development between economic…
Abstract
Purpose
The purpose of this paper is to generate quantitative managerial insights for the improvement of the energy-saving potential and the coordinated development between economic growth and environmental protection.
Design/methodology/approach
A novel data envelopment analysis (DEA) model, based on the classical DEA theory, is developed from the perspective of emission reduction.
Findings
The empirical results indicate that China’s overall environmental efficiency is low and that there is huge improvement space for energy saving. Under the concerns of emission reduction, the energy-saving potential of the central region exceeds that of both the eastern and western regions. With regard to water, electricity and gas consumption, the electricity-saving potential exceeds the potential for both water saving and gas saving.
Originality/value
Previous studies rarely focused on the energy-saving potential, while considering environmental pollution. This paper applies a novel DEA method to evaluate the energy-saving potential of 30 Chinese provinces for 2015 with a focus on emission reduction concerns. Furthermore, both regional differences and energy type differences of the saving potential were analyzed.
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Yong Wu, Linqian Zhang, Zelong Wei and Mingjun Hou
This paper aims to explore the effects of holistic cognition frame on novelty-centered business model design and efficiency-centered business model design. Moreover, the authors…
Abstract
Purpose
This paper aims to explore the effects of holistic cognition frame on novelty-centered business model design and efficiency-centered business model design. Moreover, the authors consider how these effects differ in new ventures vs established firms.
Design/methodology/approach
The authors use survey data to testify the hypotheses based on a database of 204 firms in China. Then, regression analysis is used to examine the relationship between holistic cognition frame and business model design. They also explore the contingency effects of new ventures and established firms on the relationships.
Findings
The authors find that the holistic cognition frame has a positive effect on efficiency-centered business model design, whereas it has an inverse U-shaped effect on novelty-centered business model design. Furthermore, they find that the effects of holistic cognition frame on efficiency-centered business model design and novelty-centered business model design are different in established firms and new ventures.
Originality/value
This work offers new insights into the effects of holistic cognition frame on business model design and provides useful suggestions for firms to promote business model design.
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Keywords
Mingjun Yang, Tuan Trong Luu and Dan Wang
Internal knowledge transfer is crucial for firms to improve their employees’ abilities and improve their work performance. However, there is still a gap in the knowledge…
Abstract
Purpose
Internal knowledge transfer is crucial for firms to improve their employees’ abilities and improve their work performance. However, there is still a gap in the knowledge management field regarding whether internal knowledge transfer can leverage employee personality traits and service performance in service-oriented organizations. To address this gap, this study aims to validate a multilevel model of the mediating (i.e. internal knowledge transfer as a mediator) and moderating (i.e. task interdependence as a moderator) mechanisms underlying personality traits and employee service performance.
Design/methodology/approach
Multilevel structural equation modeling was applied for model validation using an original data set from 45 team leaders and 333 employees working in Chinese hotels.
Findings
Internal knowledge transfer mediated the link between extraversion and employee service performance and the link between openness to experience and employee service performance. Task interdependence played a moderating role that strengthened both the impacts of extraversion and openness to experience on internal knowledge transfer.
Originality/value
Through the use of an original data set, this study advances the knowledge management discipline by investigating the mediating impact of internal knowledge transfer between personality traits and employee service performance and revealing the moderating impact of task interdependence that underlies the links between personality traits and internal knowledge transfer.
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Haotian Cao, Zhenghao Zhang, Xiaolin Song, Hong Wang, Mingjun Li, Song Zhao and Jianqiang Wang
The purpose of this paper is to investigate the influence of driver demographic characteristics on the driving safety involving cell phone usages.
Abstract
Purpose
The purpose of this paper is to investigate the influence of driver demographic characteristics on the driving safety involving cell phone usages.
Design/methodology/approach
A total of 1,432 crashes and 19,714 baselines were collected for the Strategic Highway Research Program 2 naturalistic driving research. The authors used a case-control approach to estimate the prevalence and the population attributable risk percentage. The mixed logistic regression model is used to evaluate the correlation between different driver demographic characteristics (age, driving experience or their combination) and the crash risk regarding cell phone engagements, as well as the correlation among the likelihood of the cell phone engagement during the driving, multiple driver demographic characteristics (gender, age and driving experience) and environment conditions.
Findings
Senior drivers face an extremely high crash risk when distracted by cell phone during driving, but they are not involved in crashes at a large scale. On the contrary, cell phone usages account for a far larger percentage of total crashes for young drivers. Similarly, experienced drivers and experienced-middle-aged drivers seem less likely to be impacted by the cell phone while driving, and cell phone engagements are attributed to a lower percentage of total crashes for them. Furthermore, experienced, senior or male drivers are less likely to engage in cell phone-related secondary tasks while driving.
Originality/value
The results provide support to guide countermeasures and vehicle design.
Details
Keywords
Junting Lin, Mingjun Ni and Huadian Liang
This study aims to propose an adaptive fractional-order sliding mode controller to solve the problem of train speed tracking control and position interval control under…
Abstract
Purpose
This study aims to propose an adaptive fractional-order sliding mode controller to solve the problem of train speed tracking control and position interval control under disturbance environment in moving block system, so as to improve the tracking efficiency and collision avoidance performance.
Design/methodology/approach
The mathematical model of information interaction between trains is established based on algebraic graph theory, so that the train can obtain the state information of adjacent trains, and then realize the distributed cooperative control of each train. In the controller design, the sliding mode control and fractional calculus are combined to avoid the discontinuous switching phenomenon, so as to suppress the chattering of sliding mode control, and a parameter adaptive law is constructed to approximate the time-varying operating resistance coefficient.
Findings
The simulation results show that compared with proportional integral derivative (PID) control and ordinary sliding mode control, the control accuracy of the proposed algorithm in terms of speed is, respectively, improved by 25% and 75%. The error frequency and fluctuation range of the proposed algorithm are reduced in the position error control, the error value tends to 0, and the operation trend tends to be consistent. Therefore, the control method can improve the control accuracy of the system and prove that it has strong immunity.
Originality/value
The algorithm can reduce the influence of external interference in the actual operating environment, realize efficient and stable tracking of trains, and ensure the safety of train control.
Details
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Mingjun Yang, Tuan Luu and Dan Wang
The quality of service determines whether service firms can satisfy customers and achieve business quality and sustainability. As contemporary service firms are dependent on both…
Abstract
Purpose
The quality of service determines whether service firms can satisfy customers and achieve business quality and sustainability. As contemporary service firms are dependent on both team and employee to serve customers, it is important to investigate how to simultaneously facilitate team service performance (TSP) and employee service performance (ESP). Our aim is to build a multilevel model of the curvilinear effect of task conflict (TC) on TSP and ESP, as well as the moderating effects underlying the above curvilinear relationships.
Design/methodology/approach
Two-sourced data were obtained from 47 team leaders and 326 employees in Chinese hotels. Multilevel structural equation modeling was utilized for validating the model.
Findings
The results revealed that TC exerted a curvilinear effect on both TSP and ESP. Ethical climate (EC) and internal knowledge transfer (IKT) served as moderators strengthening the curvilinear nexus between TC and ESP.
Originality/value
We contribute to the conflict-performance stream in management literature by unmasking the curvilinear effects of TC on both TSP and ESP, and the moderation mechanisms underlying such curvilinear effects.
Details
Keywords
Mingjun Yang, Tuan Trong Luu and David Qian
Service innovative behavior from employees helps hospitality organizations gain a competitive advantage and sustain business flourishment. Although group diversity has been…
Abstract
Purpose
Service innovative behavior from employees helps hospitality organizations gain a competitive advantage and sustain business flourishment. Although group diversity has been demonstrated as a predictor of employee outcomes, whether group diversity in terms of extraversion and openness enhances employee service innovative behavior remains a gap. This study aims to fill this gap by developing a multilevel model of the direct relationship between group diversity in terms of extraversion and openness and employee service innovative behavior and also the mediations and moderations behind the relationship.
Design/methodology/approach
The authors collectd data from 44 Chinese hospitality teams. The research model was validated by multilevel structural equation modeling.
Findings
Results showed that both group extraversion diversity and group openness diversity fostered employee service innovative behavior via creative self-efficacy. Developmental culture strengthened the effectiveness of group openness diversity on creative self-efficacy and the effectiveness of creative self-efficacy on employee service innovative behavior. Nevertheless, developmental culture did not strengthen the effectiveness of group extraversion diversity on creative self-efficacy.
Practical implications
Findings suggest that managers and team leaders from hospitality organizations can elicit employee service innovative behavior through increasing group diversity in terms of extraversion and openness. Hospitality practitioners also should understand that employees’ confidence for creativity is able to channel group diversity into employee service innovative endeavors. Moreover, building developmental culture is essential for hospitality teams to strengthen the effect of group diversity on innovating services.
Originality/value
This study expands the diversity-innovation research through unfolding both the mediations and the moderations behind the link between group diversity in terms of extraversion and openness and employee service innovative behavior.
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