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1 – 10 of over 12000Yongxing Guo, Min Chen, Li Xiong, Xinglin Zhou and Cong Li
The purpose of this study is to present the state of the art for fiber Bragg grating (FBG) acceleration sensing technologies from two aspects: the principle of the measurement…
Abstract
Purpose
The purpose of this study is to present the state of the art for fiber Bragg grating (FBG) acceleration sensing technologies from two aspects: the principle of the measurement dimension and the principle of the sensing configuration. Some commercial sensors have also been introduced and future work in this field has also been discussed. This paper could provide an important reference for the research community.
Design/methodology/approach
This review is to present the state of the art for FBG acceleration sensing technologies from two aspects: the principle of the measurement dimension (one-dimension and multi-dimension) and the principle of the sensing configuration (beam type, radial vibration type, axial vibration type and other composite structures).
Findings
The current research on developing FBG acceleration sensors is mainly focused on the sensing method, the construction and design of the elastic structure and the design of a new information detection method. This paper hypothesizes that in the future, the following research trends will be strengthened: common single-mode fiber grating of the low cost and high utilization rate; high sensitivity and strength special fiber grating; multi-core fiber grating for measuring single-parameter multi-dimensional information or multi-parameter information; demodulating equipment of low cost, small volume and high sampling frequency.
Originality/value
The principle of the measurement dimension and principle of the sensing configuration for FBG acceleration sensors have been introduced, which could provide an important reference for the research community.
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Fertilizer overuse is regarded as one of the main contributors to agricultural pollution and environmental problems in China. The purpose of this paper is to evaluate technical…
Abstract
Purpose
Fertilizer overuse is regarded as one of the main contributors to agricultural pollution and environmental problems in China. The purpose of this paper is to evaluate technical efficiency (TE) and fertilizer overuse index (FOI) with respect to China’s arable agricultural production and examine regional variations in terms of fertilizer overuse.
Design/methodology/approach
The maximum likelihood random effects–time varying inefficiency effects model was applied to estimate TE, fertilizer use efficiency (FUE) and FOI.
Findings
Over the study period (2011–2015), TE steadily increased for each individual province. Overall, mean annual TE was 0.811, implying that, on average, Chinese provinces could increase output by 18.9 per cent given unchanged levels of inputs and technology. Mean annual FOI ranged from 0.008 to 3.139, with a mean of 0.685, suggesting that there is fertilizer overuse in almost all provinces, and that large regional variation exists. Coastal provinces were found to have the highest TE scores, while the central region showed the highest degree of fertilizer overuse.
Originality/value
The results indicate that fertilizer use has had a significant positive impact on production in the China’s arable agricultural sector. High TE was not necessarily associated with low FUE.
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Xiangyu Wang, Pei He, Qinglong Zhou, Qingyuan Zhou, Manlang Cheng, Yangting Sun, Yiming Jiang, Laizhu Jiang and Jin Li
The purpose of this study is to investigate the intergranular corrosion (IGC) susceptibility of a nitrogen-containing austenitic stainless steel QN2109. The intergranular…
Abstract
Purpose
The purpose of this study is to investigate the intergranular corrosion (IGC) susceptibility of a nitrogen-containing austenitic stainless steel QN2109. The intergranular corrosion (IGC) susceptibility of a nitrogen-containing austenitic stainless steel QN2109 was investigated.
Design/methodology/approach
The double-loop electrochemical potentiodynamic reactivation (DL-EPR) tests were carried out. Scanning electron microscopy and atomic force microscopy were used to characterize the microstructure.
Findings
The optimized test condition for QN2109 was 1 M H2SO4 + 0.01 M NH4SCN at 40°C. The nose temperature of the temperature–time–sensitization (TTS) curve of QN2109 plot was approximately 750°C. Moreover, the IGC susceptibility started to appear at approximately 120 min. The Cr-depletion zone of QN2109 was generated by the formation of M23C6 rather than by the addition of nitrogen. The depth–width ratio of the grain boundaries after the DL-EPR tests decreased as the aging temperature increased. The degree of Cr depletion and size of the Cr-depletion zone at the grain boundary were reflected by the degree of sensitization and depth–width ratio, respectively.
Originality/value
The optimized test condition for DL-EPR tests of a nitrogen-containing austenitic stainless steel QN2109 was investigated. The TTS curve of QN2109 was first plotted to avoid IGC failure. The morphology of the Cr-depletion zone was reflected by the depth–width ratio.
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Ling Jiang and Juan Shan
Despite the growing research regarding consumer luxury value perception and their influence on luxury consumption behavior in different cultural contexts, there is little research…
Abstract
Purpose
Despite the growing research regarding consumer luxury value perception and their influence on luxury consumption behavior in different cultural contexts, there is little research investigating the cultural variation toward luxury within different generations in a given society. The purpose of this paper is to assess the relationships among Confucian propriety, luxury value perception, and purchase intention of luxury brands, and especially how these relationships differ between young and older consumers in a Chinese context.
Design/methodology/approach
Data were collected through a questionnaire survey in China. A multi-group structural equation model was used to test the conceptual model and research hypotheses.
Findings
The results show that the effects of functional value and social value on purchase intention of luxury brands are stronger for older generations than younger ones, while the effects of self-identity and hedonic value on purchase intention are stronger for younger generations than older ones. The Confucian propriety relates positively to the functional value and social value; however, these effects are more salient for older consumers.
Originality/value
The results of this study reveal the evolution of luxury consumption values and behaviors of Chinese consumers, suggesting that marketers should no longer label Chinese luxury consumers with common behaviors. It is also recommended that marketers of luxury brands in China should adapt this shifting attitude and respond actively to the expectations of different generations.
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Bo Zeng, Shaowei Fan, Li Jiang and Hong Liu
This paper aims to present the design and experiment of a modular multisensory prosthetic hand for applications. Design and experiment of a modular multisensory hand for…
Abstract
Purpose
This paper aims to present the design and experiment of a modular multisensory prosthetic hand for applications. Design and experiment of a modular multisensory hand for prosthetic applications.
Design/methodology/approach
This paper reveals more details focusing on the appearance, mechanism design, electrical design and control of the prosthetic hand considering anthropomorphism, dexterity, sensing and controllability. The finger is internally integrated with the actuator, the transmission mechanism, the sensors and the controller as a modular unit. Integrated with multiple sensors, the prosthetic hand can not only perceive the position, the contact force and the temperature of the environment like a human hand but also provide the foundation for the practical control.
Findings
The experiments show that the prosthetic hand can accurately control the contact force to achieve stable grasps based on the sensors feedback and a simple and effective force-tracking impedance control algorithm. In addition, the experiments based on the cosmesis validate not only the cosmesis functionality but also the control performance for a prosthesis–cosmesis system.
Practical implications
Because of the small size, low weight, high integration, modularity and controllability, the prosthetic hand is easily applied to upper-limb amputees. Meanwhile, the finger as a modular unit is easy to be fixed, maintained and applied to a partial upper-limb amputee.
Originality/value
Each modular finger of the prosthetic hand integrated with the actuator, the transmission mechanism, the sensors and the controller as a whole can independently control the position and the force. The cosmetic glove design can provide pretty appearance without compromising the control performance.
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Li Jiang, Qi Huang, Dapeng Yang, Shaowei Fan and Hong Liu
The purpose of this study is to present a novel hybrid closed-loop control method together with its performance validation for the dexterous prosthetic hand.
Abstract
Purpose
The purpose of this study is to present a novel hybrid closed-loop control method together with its performance validation for the dexterous prosthetic hand.
Design/methodology/approach
The hybrid closed-loop control is composed of a high-level closed-loop control with the user in the closed loop and a low-level closed-loop control for the direct robot motion control. The authors construct the high-level control loop by using electromyography (EMG)-based human motion intent decoding and electrical stimulation (ES)-based sensory feedback. The human motion intent is decoded by a finite state machine, which can achieve both the patterned motion control and the proportional force control. The sensory feedback is in the form of transcutaneous electrical nerve stimulation (TENS) with spatial-frequency modulation. To suppress the TENS interfering noise, the authors propose biphasic TENS to concentrate the stimulation current and the variable step-size least mean square adaptive filter to cancel the noise. Eight subjects participated in the validation experiments, including pattern selection and egg grasping tasks, to investigate the feasibility of the hybrid closed-loop control in clinical use.
Findings
The proposed noise cancellation method largely reduces the ES noise artifacts in the EMG electrodes by 18.5 dB on average. Compared with the open-loop control, the proposed hybrid closed-loop control method significantly improves both the pattern selection efficiency and the egg grasping success rate, both in blind operating scenarios (improved by 1.86 s, p < 0.001, and 63.7 per cent, p < 0.001) or in common operating scenarios (improved by 0.49 s, p = 0.008, and 41.3 per cent, p < 0.001).
Practical implications
The proposed hybrid closed-loop control method can be implemented on a prosthetic hand to improve the operation efficiency and accuracy for fragile objects such as eggs.
Originality/value
The primary contribution is the proposal of the hybrid closed-loop control, the spatial-frequency modulation method for the sensory feedback and the noise cancellation method for the integrating of the myoelectric control and the ES-based sensory feedback.
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Bo Zeng, Hongwei Liu, Hongzhou Song, Zhe Zhao, Shaowei Fan, Li Jiang, Yuan Liu, Zhiyuan Yu, Xiaorong Zhu, Jing Chen and Ting Zhang
The purpose of this paper is to design a multi-sensory anthropomorphic prosthetic hand and a grasping controller that can detect the slip and automatically adjust the grasping…
Abstract
Purpose
The purpose of this paper is to design a multi-sensory anthropomorphic prosthetic hand and a grasping controller that can detect the slip and automatically adjust the grasping force to prevent the slip.
Design/methodology/approach
To improve the dexterity, sensing, controllability and practicability of a prosthetic hand, a modular and multi-sensory prosthetic hand was presented. In addition, a slip prevention control based on the tactile feedback was proposed to improve the grasp stability. The proposed controller identifies slippages through detecting the high-frequency vibration signal at the sliding surface in real time and the discrete wavelet transform (DWT) was used to extract the eigenvalues to identify slippages. Once the slip is detected, a direct-feedback method of adjusting the grasp force related with the sliding times was used to prevent it. Furthermore, the stiffness of different objects was estimated and used to improve the grasp force control. The performances of the stiffness estimation, slip detection and slip control are experimentally evaluated.
Findings
It was found from the experiment of stiffness estimation that the accuracy rate of identification of the hard metal bottle could reach to 90%, while the accuracy rate of identification of the plastic bottles could reach to 80%. There was a small misjudgment rate in the identification of hard and soft plastic bottles. The stiffness of soft plastic bottles, hard plastic bottles and metal bottles were 0.64 N/mm, 1.36 N/mm and 32.55 N/mm, respectively. The results of slip detection and control show that the proposed prosthetic hand with a slip prevention controller can fast and effectively detect and prevent the slip for different disturbances, which has a certain application prospect.
Practical implications
Due to the small size, low weight, high integration and modularity, the prosthetic hand is easily applied to upper-limb amputees. Meanwhile, the method of the slip prevention control can be used for upper-limb amputees to complete more tasks stably in daily lives.
Originality/value
A multi-sensory anthropomorphic prosthetic hand is designed, and a method of stable grasps control based on slip detection by a tactile sensor on the fingertip is proposed. The method combines the stiffness estimation of the object and the real-time slip detection based on DWT with the design of the proportion differentiation robust controller based on a disturbance observer and the force controller to achieve slip prevention and stable grasps. It is verified effectively by the experiments and is easy to be applied to commercial prostheses.
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Yi-Hsin Lin, Wenqing Han, Chan Joong Kim, Li Jiang and Nini Xia
The purpose of this paper is to verify the mediating role of commitment between market-oriented organizational culture and international market performance, and to discuss the…
Abstract
Purpose
The purpose of this paper is to verify the mediating role of commitment between market-oriented organizational culture and international market performance, and to discuss the moderator effect of national institutional environment on this mediating role.
Design/methodology/approach
The research design follows a mixed methodology, combining qualitative and quantitative data collection and analysis. In the first phase, research hypotheses are proposed based on a literature analysis. In the second phase, sample data are collected through interviews and questionnaires sent to domestic contractors in China and South Korea, and a validity analysis of the results is carried out. Correlation and regression analyses are then performed on the valid data to verify hypotheses to prove the existence and influence of mediating effects. Hayes PROCESS Macro is used on the regression results to test the mediating effect of commitment on international project performance and the moderation effect of institutional environment.
Findings
The results reveal that the commitment between partners has a mediating effect on the relationship between market culture and international project performance; however, no hierarchy culture is revealed. The mediating effect of commitment is regulated by the institutional environment.
Research limitations/implications
Although the reliability and validity of the questionnaire data in this study are in line with research standards, a larger sample size would improve the reliability of the results. Further, the interviewed samples are mainly from China and South Korea; large representative samples from additional countries, such as Japan, should be considered to gain a fuller understanding and more comprehensive results.
Originality/value
By emphasizing the differences between the two institutional environments of developing and developed countries in East Asia, a theoretical and empirical basis is provided. International construction enterprises in other countries can apply the findings to improve their international market performance in different institutional environments. The findings also provide an empirical reference that international construction enterprises in China and South Korea may use to adjust their organizational cultures and commitments to improve market performance.
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Xuefeng Zhou, Li Jiang, Yisheng Guan, Haifei Zhu, Dan Huang, Taobo Cheng and Hong Zhang
Applications of robotic systems in agriculture, forestry and high-altitude work will enter a new and huge stage in the near future. For these application fields, climbing robots…
Abstract
Purpose
Applications of robotic systems in agriculture, forestry and high-altitude work will enter a new and huge stage in the near future. For these application fields, climbing robots have attracted much attention and have become one central topic in robotic research. The purpose of this paper is to propose an energy-optimal motion planning method for climbing robots that are applied in an outdoor environment.
Design/methodology/approach
First, a self-designed climbing robot named Climbot is briefly introduced. Then, an energy-optimal motion planning method is proposed for Climbot with simultaneous consideration of kinematic constraints and dynamic constraints. To decrease computing complexity, an acceleration continuous trajectory planner and a path planner based on spatial continuous curve are designed. Simulation and experimental results indicate that this method can search an energy-optimal path effectively.
Findings
Climbot can evidently reduce energy consumption when it moves along the energy-optimal path derived by the method used in this paper.
Research limitations/implications
Only one step climbing motion planning is considered in this method.
Practical implications
With the proposed motion planning method, climbing robots applied in an outdoor environment can commit more missions with limit power supply. In addition, it is also proved that this motion planning method is effective in a complicated obstacle environment with collision-free constraint.
Originality/value
The main contribution of this paper is that it establishes a two-planner system to solve the complex motion planning problem with kinodynamic constraints.
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Prince Ewudzie Quansah, Yongyue Zhu and Anthony Frank Obeng
This paper aims to investigate the effect of mining supervisor behaviour, safety motivation and perceived job insecurity on Ghanaian underground miner’s safety citizenship…
Abstract
Purpose
This paper aims to investigate the effect of mining supervisor behaviour, safety motivation and perceived job insecurity on Ghanaian underground miner’s safety citizenship behaviour.
Design/methodology/approach
The authors proposed a conceptual framework that tested supervisor behaviour as an independent variable, safety motivation as a mediator variable, perceived job insecurity as a moderator variable and safety citizenship behaviour as a dependent variable. The authors tested the hypothesized relationships using 351 valid responses collected through a structured questionnaire using hierarchical regression analysis.
Findings
Results revealed that both components of supervisor behaviour significantly influenced safety motivation and safety citizenship behaviour. Furthermore, safety motivation could mediate the relationships between both components of supervisor behaviour and safety citizenship behaviour. Also, perceived job insecurity failed to moderate the relationship between safety motivation and safety citizenship behaviour.
Originality/value
This current study is vital for managerial practices. The complex conceptual framework also contributes to offering different ways of understanding how supervisors’ behaviours can catalyze improvement or worsen safety outcomes.
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