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1 – 10 of 53The purpose of this paper is to present the sensing mechanism, design issues, performance evaluation and applications for planar capacitive sensors. In the context of…
Abstract
Purpose
The purpose of this paper is to present the sensing mechanism, design issues, performance evaluation and applications for planar capacitive sensors. In the context of characterisation and imaging of a dielectric material under test (MUT), a systematic study of sensor modelling, features and design issues is needed. In addition, the influencing factors on sensitivity distribution, and the effect of conductivity on sensor performance need to be further studied for planar capacitive sensors.
Design/methodology/approach
While analytical methods can provide accurate solutions to sensors of simple geometries, numerical modelling is preferred to obtain sensor response to different design parameters and properties of MUT, and to derive the sensitivity distributions of various electrode designs. Several important parameters have been used to evaluate the response of the sensors in different sensing modes. The designs of different planar capacitive sensor arrays are presented and experimentally evaluated.
Findings
The response features and design guidelines for planar capacitive sensors in different sensing modes have been summarised, showing that the sensor in the transmission mode or the single‐electrode mode is suitable for material characterisation and imaging, while the sensor in the shunt mode is suitable for proximity/displacement measurement. The sensitivity distribution of the sensor depends largely on the geometry of the electrodes. Conductivity causes positive changes for the sensor in the transmission and single‐electrode mode, but negative changes for the sensor in the shunt mode. Experimental results confirm that sensing depths of the sensor arrays and the influence of buried conductor on capacitance measurements are in agreement with simulations.
Research limitations/implications
Experimental verification is needed when a sensor is designed.
Originality/value
This paper provides a comprehensive study for planar capacitive sensors in terms of sensor design, evaluation and applications.
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Peiwen Sun, Jianwei Yang, AiHua Zhu, Zhongshuo Hu, Jinhai Wang, Fu Liu and Xiaohui Wang
The CL60 steel wheels of subway vehicles operating on specific lines require frequent refurbishment due to rapid wear and tear. Considering this issue, MoS2-based and…
Abstract
Purpose
The CL60 steel wheels of subway vehicles operating on specific lines require frequent refurbishment due to rapid wear and tear. Considering this issue, MoS2-based and graphite-based solid lubricants are used to reduce the wear rate of subway wheels and extend their service life.
Design/methodology/approach
Under laboratory conditions, the effect of MoS2-based and graphite-based solid lubricants on the friction and wear performance of subway wheels and rails was evaluated using a modified GPM-60 wear testing machine.
Findings
Under laboratory conditions, MoS2-based solid lubricants have the best effect in reducing wheel/rail wear, compared to the control group without lubrication, at 2 × 105 revolutions, the total wheel-rail wear decreased by 95.07%. However, when three types of solid lubricants are used separately, the hardness evolution of the wheel-rail contact surface exhibits different characteristics.
Practical implications
The research results provide important support for improving the lifespan of wheel and rail, extending the service cycle of wheel and rail, reducing the operating costs of subway systems, improving the safety of subway systems and providing wear reduction maintenance for other high wear mechanical components.
Originality/value
The experiment was conducted through the design and modification of a GPM-60 testing machine for wear testing. The experiment simulated the wheel-rail contact situation under actual subway operation and evaluated the effects of three different solid lubricants, MoS2-based and graphite-based, on the wear performance and surface hardening evolution of subway wheel-rail.
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Xiaohui Yu, Fei Wang and Lina Wang
City wall is an important symbol of ancient Chinese cities with unique geographical and cultural characteristics. Thus, the preservation of this historic landmark is considered…
Abstract
City wall is an important symbol of ancient Chinese cities with unique geographical and cultural characteristics. Thus, the preservation of this historic landmark is considered significantly important. However, numerous residential construction activities and changes in ecological environment have destructed a great portion of the city walls in recent years. This study looks into the preservation of the ancient city walls from the systematic perspective and in line with the actual characteristics of Longdong Region to provide guideline measures for the protection and restoration of such landmark. Cognition and preservation are adopted extensively to investigate the specific situation of and the factors that influence the ancient city walls in this region. Preservation strategies for the city walls, including the “Axis-Point” system, planning control, and authenticity readability, are presented. The ancient city walls in Longdong Region can be preserved by protecting the entire region, the city, and the main wall body. The systematic method and preservation strategies at the “macro perspective,” “medium perspective” and “micro perspective” levels can solve the preservation problems of the ancient city walls in Longdong Region effectively.
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Dalei Zhang, Xinwei Zhang, Enze Wei, Xiaohui Dou and Zonghao He
This study aims to improve the corrosion resistance of TA2-welded joints by superhydrophobic surface modification using micro-arc oxidation technology and low surface energy…
Abstract
Purpose
This study aims to improve the corrosion resistance of TA2-welded joints by superhydrophobic surface modification using micro-arc oxidation technology and low surface energy substance modification.
Design/methodology/approach
The microstructure and chemical state of the superhydrophobic film layer were analyzed using scanning electron microscopy, energy dispersive X-ray spectroscopy, three-dimensional morphology, X-ray diffraction, X-ray photoelectron spectroscopy and Fourier transform infrared absorption spectroscopy. The influence of the superhydrophobic film layer on the corrosion resistance of TA2-welded joints was investigated using classical electrochemical testing methods.
Findings
The characterization results showed that the super hydrophobic TiO2 ceramic membrane was successfully constructed on the surface of the TA2-welded joint, and the construction of the super hydrophobic film greatly improved the corrosion resistance of the TA2-welded joint.
Originality/value
The superhydrophobic TiO2 ceramic membrane has excellent corrosion resistance. The micro nanostructure in the superhydrophobic film can intercept air to form an air layer to prevent the corrosion medium from contacting the surface, thus, improving the corrosion resistance of the sample.
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Haibo Wu, Xiaohui Wang and Peter Chen
Drawing on the transaction theory of stress, the purpose of this paper is to conceptualize customer mistreatment as a stressor and examine how job routinization and proactive…
Abstract
Purpose
Drawing on the transaction theory of stress, the purpose of this paper is to conceptualize customer mistreatment as a stressor and examine how job routinization and proactive personality help employees cope with the effects of customer mistreatment on emotional exhaustion and work engagement. The interaction of job routinization and proactive personality was also tested.
Design/methodology/approach
In total, 128 hundred nurses were recruited to participate in the current study, which was a daily survey for two consecutive weeks (10 working days).
Findings
The results revealed that job routinization and proactive personality attenuated the effects of customer mistreatment on emotional exhaustion and work engagement. The analyses also showed that, with more proactive personality and high job routinization, the effects of customer mistreatment were minimized.
Originality/value
Job routinization is a type of job resources that attenuates the negative influence of customer mistreatment. Proactive personality strengthens job routinization’s function, when proactive personality and job routinization are both high, the ill effect of customer mistreatment will be minimized.
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Jialiang Xie, Wenxin Wang, Yanling Chen, Feng Li and Xiaohui Liu
The purpose of this paper is to develop a novel interval Multi-Objective Optimization by a Ratio Analysis plus the Full Multiplicative Form(MULTIMOORA) with combination weights to…
Abstract
Purpose
The purpose of this paper is to develop a novel interval Multi-Objective Optimization by a Ratio Analysis plus the Full Multiplicative Form(MULTIMOORA) with combination weights to evaluate the employment quality of college graduates, where the criteria are expressed by interval numbers and the weights of criteria are completely unknown.
Design/methodology/approach
Firstly, considering the subjective uncertainty of the weights of the criteria, the interval best worst method (I-BWM) was present to determine the subjective weights of the criteria. Secondly, by the improved interval number distance measure, an improved interval deviation maximization method (I-MDM) was introduced to detemine the objective weights. In the following, based on the I-BWM and the improved I-MDM, a combination weighting method that takes into account the subjective and objective weights is proposed. Finally, a multi-criteria decision-making method based on the interval MULTIMOORA with combination weights is present to evaluate the employment quality of college graduates, and then a comparative analysis with some of the existing distance measures of interval numberswas conducted to illustrate the flexibility.
Findings
According to the data of the Report on Employment Quality of Chinese College Graduats released by Mycos Research Institute in 2016–2020 and 2021–2022, the proposed method was used to evaluate the employment quality of college graduates during the period before and after the COVID-19 epidemic. The results verify that the method is more reasonable because the subjective and objective weights of the criteria can be fully considered. Finally, the feasibility and practicability of the proposed method are further verified by varying parameters.
Originality/value
Present an evaluation method on the employment quality of college graduates based on the Interval MULTIMOORA with combination weights considering the subjective and objective weights. And the proposed method is proved that it can provide a more reasonable evaluation results. At the same time, it is verified that the feasibility and the practicability of the proposed method are affected by varying parameters in the paper.
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Wenqing Kan, Ying Huang, Xiao Zeng, Xiaohui Guo and Ping Liu
The purpose of this paper is to present a dual-mode proximity sensor composed of inductive and capacitive sensing modes, which can help the robot distinguish different objects and…
Abstract
Purpose
The purpose of this paper is to present a dual-mode proximity sensor composed of inductive and capacitive sensing modes, which can help the robot distinguish different objects and obtain distance information at the same time. A systematic study of sensor response to various objects and the function of cooperation sensing is needed. Furthermore, the application in the field of robotic area needs to be discussed.
Design/methodology/approach
Numerical modeling of each sensing modes and simulations based on finite element analysis method has been carried out to verify the designed dual-mode sensor. A number of objects composed of different materials are used to research the cooperation perception and proximity sensing functions. In addition, the proposed sensor is used on the palm of a mechanical hand as application experiment.
Findings
The characteristics of the sensor are summarized as follows: the sensing range of inductive mode is 0-5.6 mm for detecting a copper block and the perceive range of capacitive mode is 0-5.1 mm for detecting a plastic block. The collaborative perceive tests validated that the non-ferromagnetism metals can be distinguished by inductive mode. Correspondingly, ferromagnetism metals and dielectric objects are differentiated by capacitive mode. Application experiments results reveal that both plastic bottle and steel bottle could be detected and differentiated. The experimental results are in agreement with those of simulations.
Originality value
This paper provides a study of dual-mode proximity sensor in terms of design, experiments and application.
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Ying Huang, Chao Hao, Jian Liu, Xiaohui Guo, Yangyang Zhang, Ping Liu, Caixia Liu, Yugang Zhang and Xiaoming Yang
The purpose of this study is to present a highly stretchable and flexible strain sensor with simple and low cost of fabrication process and excellent dynamic characteristics…
Abstract
Purpose
The purpose of this study is to present a highly stretchable and flexible strain sensor with simple and low cost of fabrication process and excellent dynamic characteristics, which make it suitable for human motion monitoring under large strain and high frequency.
Design/methodology/approach
The strain sensor was fabricated using the rubber/latex polymer as elastic carrier and single-walled carbon nanotubes (SWCNTs)/carbon black (CB) as a synergistic conductive network. The rubber/latex polymer was pre-treated in naphtha and then soaked in SWCNTs/CB/silicon rubber composite solution. The strain sensing and other performance of the sensor were measured and human motion tracking applications were tried.
Findings
These strain sensors based on aforementioned materials display high stretchability (500 per cent), excellent flexibility, fast response (approximately 45 ms), low creep (3.1 per cent at 100 per cent strain), temperature and humidity independence, superior stability and reproducibility during approximately 5,000 stretch/release cycles. Furthermore, the authors used these composites as human motion sensors, effectively monitoring joint motion, indicating that the stretchable strain sensor based on the rubber/latex polymer and the synergetic effects of mixed SWCNTs and CB could have promising applications in flexible and wearable devices for human motion tracking.
Originality/value
This paper presents a low-cost and a new type of strain sensor with excellent performance that can open up new fields of applications in flexible, stretchable and wearable electronics, especially in human motion tracking applications where very large strain should be accommodated by the strain sensor.
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Digital economic innovation is associated with risks. The lack of a platform's profitability weakens the operation's ability to sustain innovators and increases the possibility of…
Abstract
Purpose
Digital economic innovation is associated with risks. The lack of a platform's profitability weakens the operation's ability to sustain innovators and increases the possibility of the business' termination. Relevant data demonstrate a significant upward trend in the exit of Chinese innovators of the digital economy. The study aims to clarify the role of an effective government and effective market in the prevention and control of the withdrawal of innovators.
Design/methodology/approach
Based on balanced panel data of 31 provinces and cities from 2010 to 2018, this study uses the individual fixed effect model to study the impact of the marketization level, the market's scale and government interventions on the withdrawal of innovators. Simultaneously, based on the spatial econometric model, this study examines the spatial spillover effect of the withdrawal of innovators.
Findings
Results indicate that government interventions have an inhibiting effect on the withdrawal of innovators. Moreover, there was a positive “U”-shaped nonlinear relationship between the marketization level and the withdrawal of innovators, and an inverse “U”-shaped nonlinear relationship between the market size and the withdrawal of innovators.
Originality/value
The paper first studies the relationship between the exit of innovators and government intervention, marketization level and field scale; takes the lead in the research on the role of the government and effective market in the prevention and control of the exit of innovators from the perspective of the exit of innovators and puts forward policy suggestions to promote the sustainable and healthy development of fintech innovation in China from the market scale and other aspects.
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Rong Song, Xiaohui Jiao and Long Lin
The purpose of this paper is to investigate the effects of nano‐titanium dioxide and nano‐silicon dioxide particles on the mechanical and antimicrobial properties of denture base…
Abstract
Purpose
The purpose of this paper is to investigate the effects of nano‐titanium dioxide and nano‐silicon dioxide particles on the mechanical and antimicrobial properties of denture base resin.
Design/methodology/approach
Nano‐titanium dioxide and nano‐silicon dioxide particles were introduced to heat‐curing denture base resin to prepare composites. Electronic universal testing machine and friction tester were used to test tensile strength and frictional resistance properties of the samples prepared, respectively; also, film adhesion method was used to test the in vitro antimicrobial activity against Candida albicans and Streptococcus mutans.
Findings
Addition of nano‐titanium dioxide particles could improve the antimicrobial property of denture base resin, and addition of nano‐silicon dioxide particles could improve the tensile strength and frictional resistance of denture base resin. Mixture of the two nano‐particles, at a certain ratio, could improve the tensile strength, frictional resistance and antimicrobial property of denture base resin to a certain extent.
Practical implications
Nano‐titanium dioxide and nano‐silicon dioxide denture base resin composites were obtained. The mechanical and antimicrobial properties of the composites were improved compared to the raw denture base resin.
Originality/value
Nano‐titanium dioxide and nano‐silicon dioxide denture base resin composites with excellent performance could be obtained. Longer service life, greater hardness and clearness helped improve the patients' quality of life. Limited work with respect to the improved denture base resin was performed, which could form the theme of a future study. The outcomes of the research reported here set a new milestone in the field of denture base resin.
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