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1 – 10 of 33Xiongmin Tang, Zexin Zhou, Yongquan Chen, ZhiHong Lin, Miao Zhang and Xuecong Li
Dielectric barrier discharge (DBD) is widely used in the treatment of skin disease, surface modification of material and other fields of electronics. The purpose of this paper is…
Abstract
Purpose
Dielectric barrier discharge (DBD) is widely used in the treatment of skin disease, surface modification of material and other fields of electronics. The purpose of this paper is to design a high-performance power supply with a compact structure for excimer lamps in electronics application.
Design/methodology/approach
To design a high-performance power supply with a compact structure remains a challenge for excimer lamps in electronics application, a current-source type power supply in a single stage with power factor correction (PFC) is proposed. It consists of an excitation voltage generation unit and a PFC unit. By planning the modes of the excitation voltage generation unit, a bipolar pulse excitation voltage with a high rising and falling rate is generated. And a high power factor (PF) on the AC side is achieved by the interaction of a non-controlled rectifier and two inductors.
Findings
The experimental results show that not only a high-frequency and high-voltage bipolar pulse excitation voltage with a high average rising and falling rate (7.51GV/s) is generated, but also a high PF (0.992) and a low total harmonic distortion (5.54%) is obtained. Besides, the soft-switching of all power switches is realized. Compared with the sinusoidal excitation power supply and the current-source power supply, the proposed power supply in this paper can take advantage of the potential of excimer lamps.
Originality/value
A new high-performance power supply with a compact structure for DBD type excimer lamps is proposed. The proposed power supply can work stably in a wide range of frequencies, and the smooth regulation of the discharge power of the excimer lamp can be achieved by changing the switching frequency. The ideal excitation can be generated, and the soft switching can be realized. These features make this power supply a key player in the outstanding performance of the DBD excimer lamps application.
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Xiongmin Tang, Tianhong Jiang, Weizheng Chen, ZhiHong Lin, Zexin Zhou, Chen Yongquan and Miao Zhang
How to use a simple and classical topology to provide a high-efficiency excitation voltage for dielectric barrier discharge (DBD) loads is one of the primary problems to be solved…
Abstract
Purpose
How to use a simple and classical topology to provide a high-efficiency excitation voltage for dielectric barrier discharge (DBD) loads is one of the primary problems to be solved for DBD application fields.
Design/methodology/approach
To address the issue, a set of modes that can generate a high-efficiency pulse excitation voltage in a full-bridge inverter are adopted. With the set of modes, the unique equivalent circuit of DBD loads and the parasitic parameter of the step-up transformer can be fully used. Based on the set of modes, a control strategy for the full-bridge inverter is designed. To test the performance of the power supply, a simulation model is established and an experimental prototype is made with a DBD excimer lamp.
Findings
The simulation and experimental results show that not only a high-efficiency excitation voltage can be generated for the DBD load, but also the soft switching of all power switch is realized. Besides this, with the set of modes and the proposed control strategy, the inverter can operate in a high frequency. Compared with other types of power supplies, the power supply used in the paper can fully take advantage of the potential of the excimer lamp at the same input power.
Originality/value
This work considers that how to use a simple and classical topology to provide a high-efficiency excitation voltage for DBD loads is one of the primary problems to be solved for DBD application fields.
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Zhihong Tan, Ling Yuan and Qunchao Wan
Based on social cognitive theory, this study aims to explore the influence of supervisor bottom-line mentality (SBLM) on employee knowledge behavior (knowledge territorial…
Abstract
Purpose
Based on social cognitive theory, this study aims to explore the influence of supervisor bottom-line mentality (SBLM) on employee knowledge behavior (knowledge territorial behavior and knowledge sabotage behavior). The study first investigates the role of an ethical decision-making mechanism (moral disengagement) in mediating this relationship. In addition, it considers the possible boundary conditions to supplement research on the influence of SBLM in the knowledge management field.
Design/methodology/approach
The authors collected 256 data points from employees across three stages using convenience sampling. The authors then tested the proposed hypothesis using hierarchical regression and bootstrap methods.
Findings
The results demonstrated that SBLM promotes employees’ moral disengagement, leading to more knowledge territorial behavior and knowledge sabotage behavior. Furthermore, high power distance orientation among employees exacerbates the ill effects of SBLM according to the first stage of a moderated mediation model. Employees with such an orientation are more likely to respond to a SBLM by exhibiting a higher level of moral disengagement, thus increasing their knowledge territorial behavior and knowledge sabotage behavior.
Originality/value
Research on the influence of SBLM in the knowledge management field is limited. This study not only clarifies the relationships between SBLM and two types of knowledge behavior (knowledge territorial behavior and knowledge sabotage behavior) but also enriches the research on the antecedents of these two types of knowledge behavior.
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Zhihong Sun and Jing Wang
The purpose of this paper is to solve the issue of via filling and pattern plating simultaneously by concentration optimization of accelerator and leveler in the electroplating…
Abstract
Purpose
The purpose of this paper is to solve the issue of via filling and pattern plating simultaneously by concentration optimization of accelerator and leveler in the electroplating bath.
Design/methodology/approach
This paper designs a series of experiments to verify the performance of pattern plating with the via filling plating formula. Then the compositions of electroplating solution are optimized to achieve via filling and pattern plating simultaneously. Finally, the mechanism of co-plating for via and line is discussed in brief.
Findings
To achieve excellent performance for via filling and pattern plating simultaneously, proportion of additives are comprehensively considered in optimization of electroplating process. Effects of additives on the via filling and pattern plating should be taken into consideration, especially in achieving flat lines.
Originality/value
This paper discusses the different effects of accelerator and leveler on the via filling and the pattern plating, respectively. The process of co-plating for the via and the line is presented. The superfilling of via and the flat line are simultaneously obtained with the optimized via filling formula.
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Zhihong Tan, Mengxi Yang, Andrea C. Farro and Ling Yuan
Based on the cognitive appraisal theory of emotion and social comparison theory, this study explores the mediating mechanism and boundary conditions of supervisor bottom-line…
Abstract
Purpose
Based on the cognitive appraisal theory of emotion and social comparison theory, this study explores the mediating mechanism and boundary conditions of supervisor bottom-line mentality on employee presenteeism.
Design/methodology/approach
Using hierarchical regression and bootstrapping, we test the hypothesized relationships with three-stage data from 265 full-time employees in China.
Findings
Supervisor bottom-line mentality has a significant positive influence on employee presenteeism. Workplace fear of missing out plays a mediating role between supervisor bottom-line mentality and employee presenteeism. Employees’ status-striving motivation positively moderates the influence of supervisor bottom-line mentality on employees’ workplace fear of missing out and enhances the mediating effect of workplace fear of missing out.
Practical implications
Presenteeism can be detrimental to employees’ health, and ultimately leads to a decrease in organizational productivity. Research conclusions warn companies to be vigilant about supervisors’ bottom-line mentalities and to strengthen employee health management.
Originality/value
This study explains when and how supervisor bottom-line mentality affects employee health, contributing to the literature on the antecedents of presenteeism and enriching the research on supervisor bottom-line mentalities and employee and organizational outcomes. This study clarifies the emotional mechanisms and boundary conditions of supervisor bottom-line mentality affecting presenteeism.
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Qianjin Dong, Xueshan Ai, Guangjing Cao, Yanmin Zhang and Xianjia Wang
The purpose of this paper is to obtain risk indicators of water security of drought periods in which the indices of reliability, resiliency, and vulnerability are integrated.
Abstract
Purpose
The purpose of this paper is to obtain risk indicators of water security of drought periods in which the indices of reliability, resiliency, and vulnerability are integrated.
Design/methodology/approach
It is not reasonable that weight coefficients of different risk indices are often determined subjectively in conventional procedures, so the entropy weight method is introduced and chosen to solve the problem. Entropy weight method can get the weight coefficients of different risk indices objectively and is valid from the case study.
Findings
The feasibility and validity of entropy weight methods to determine weight coefficients of different risk indices objectively are recognized.
Research limitations/implications
Accessibility and availability of data are the main limitations.
Practical implications
The paper provides a more objective risk indicator of water security of drought periods for water resources managers.
Originality/value
This paper determines the weight coefficients of different risk indices for risk assessment of water security of drought periods based on hazard entropy. The paper is aimed at water resources managers and relative researchers, especially those who deal with risk assessment of water security of drought periods.
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Zhenpeng Wu, Vanliem Nguyen, Zhihong Zhang and Liangcai Zeng
The stepped topography of the friction pairs mainly causes the fluid film thickness to change in the direction of motion. In this region, there have very few topographical design…
Abstract
Purpose
The stepped topography of the friction pairs mainly causes the fluid film thickness to change in the direction of motion. In this region, there have very few topographical design methods for continuous or non-linear distribution of the fluid film. The purpose of this study is to analyze the effect of the curved surface on the performance of the liquid film.
Design/methodology/approach
First, a numerical simulation is used to solve the optimal bearing capacity and friction coefficient of the liquid film under the condition of the minimum film thickness. Then, the curved surface described by the sinusoidal curve equation is applied in the transitional region of maximum and minimum film thickness. The bearing capacity and the friction coefficient of the liquid film are respectively simulated and compared in the same condition of the minimum film thickness.
Findings
The research results show that the liquid film using the curved surface transition model, the optimal bearing capacity is significantly increased by 32 per cent while the optimal friction coefficient is clearly reduced by 38 per cent in comparison with using stepped surface model.
Originality/value
The friction pair with curved transition enables better lubrication performance of the liquid film and better adaptability under unstable conditions.
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Fubing Bao, Zhihong Mao and Limin Qiu
The purpose of this paper is to investigate the gas flow characteristics in near wall region and the velocity slip phenomenon on the wall in nano-channels based on the molecular…
Abstract
Purpose
The purpose of this paper is to investigate the gas flow characteristics in near wall region and the velocity slip phenomenon on the wall in nano-channels based on the molecular dynamics simulation.
Design/methodology/approach
An external gravity force was employed to drive the flow. The density and velocity profiles across the channel, and the velocity slip on the wall were studied, considering different gas temperatures and gas-solid interaction strengths.
Findings
The simulation results demonstrate that a single layer of gas molecules is adsorbed on wall surface. The density of adsorption layer increases with the decrease of gas temperature and with increase of interaction strength. The near wall region extents several molecular diameters away from the wall. The density profile is flatter at higher temperature and the velocity profile has the traditional parabolic shape. The velocity slip on the wall increases with the increase of temperature and with decrease of interaction strength linearly. The average velocity decreases with the increase of gas-solid interaction strength.
Originality/value
This research presents gas flow characteristics in near wall region and the velocity slip phenomenon on the wall in nano-channels. Some interesting results in nano-scale channels are obtained.
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This paper aims to examine how the official discourse of frugality evolved in China between 1979 and 2015.
Abstract
Purpose
This paper aims to examine how the official discourse of frugality evolved in China between 1979 and 2015.
Design/methodology/approach
The study uses historical and textual analysis. It divides the Chinese official discourse on frugality between 1979 and 2015 into four periods: 1979-1992, 1993-2002, 2003-2012 and 2013-2015.
Findings
A Chinese official discourse on frugality persisted between 1979 and 2015, even though during the same period, China transformed from a socialist economy of central planning and insufficient supply to a market economy of excessive supply and weak consumer demand. The intensity of this official discourse frequently vacillated, adjusting to both economic and political conditions of the time as part of the larger political-economic contestation between competing ideas and policies.
Originality/value
There have been calls for more studies on how frugality discourses have evolved in international markets, especially in terms of how they are shaped by local historical antecedents and long-standing tensions. Through the Chinese case, this article illuminates why some traditional values persist and obtain a paradoxical co-existence with consumerist ethos in our modern society.
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