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Article
Publication date: 15 May 2019

Wenqing Wu, Xin Ma, Yuanyuan Zhang, Yong Wang and Xinxing Wu

The purpose of this paper is to study a fractional grey model FAGM(1,1,tα) based on the GM(1,1,tα) model and the fractional accumulated generating operation, and then predict the…

202

Abstract

Purpose

The purpose of this paper is to study a fractional grey model FAGM(1,1,tα) based on the GM(1,1,tα) model and the fractional accumulated generating operation, and then predict the national health expenditure, the government health expenditure and the out-of-pocket health expenditure of China.

Design/methodology/approach

The presented univariate grey model is systematically studied by using the grey modelling technique, the fractional accumulated generating operation and the trapezoid approximation formula of definite integral. The optimal system parameters r and α are evaluated by the particle swarm optimisation algorithm.

Findings

The expressions of the time response function and the restored values of this model are derived. The GM(1,1), NGM(1,1,k,c) and GM(1,1,tα) models are particular cases of the FAGM(1,1,tα) model with deterministic r and α. Compared with other forecasting models, the results of the FAGM(1,1,tα) model have higher precision.

Practical implications

The superiority of the new model has high potential to be used in the medicine and health fields and others. Results can provide a guideline for government decision making.

Originality/value

The univariate fractional grey model FAGM (1,1,tα) successfully studies the China’s health expenditure.

Details

Grey Systems: Theory and Application, vol. 9 no. 2
Type: Research Article
ISSN: 2043-9377

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Article
Publication date: 14 June 2019

Xianwei Liu, Huacong Li, Xinxing Shi and Jiangfeng Fu

The purpose of this paper is to improve the hydraulic efficiency without changing the overall dimension. The blade profile optimization design of the aero-centrifugal pump based…

163

Abstract

Purpose

The purpose of this paper is to improve the hydraulic efficiency without changing the overall dimension. The blade profile optimization design of the aero-centrifugal pump based on the biharmonic equation surrogate model has been studied.

Design/methodology/approach

First of all, Bezier curves and linear function are used to control the annular angle distribution and the stacking angle of blade profile under the MATLAB platform. Grid independence analysis has been studied to find the finest mesh scheme. After the precision comparison of test data and computation fluid dynamics 15 sets of design parameters are carried out as the boundary condition of the biharmonic equation. The efficiency surrogate model of the biharmonic equation is constructed via iteratively solving of a discrete difference equation. The other two surrogate models of response surface model (RSM) and radial basis function neural network surrogate model (RBFNNSM) are compared with the biharmonic equation surrogate model by the standard of modified complex correlation coefficient R2 and root mean square deviation (RSME). Finally, the artificial fish swarm algorithm has been used to find the global optimal design parameters with the objective function of highest efficiency.

Findings

The results show that the design parameters code conversion method can reduce the number of optimization parameters from five to three, makes the design space become a cube, and compared with RSM and RBFNNSM, the biharmonic equation surrogate model has higher precision with R2 is 0.8958, RSME is 0.1382. The final optimum result of AFSA is at the point of [1 −1 −1]. The internal flow field analysis shows that after optimization the outlet relative velocity becomes more uniform and the wake effect has been significantly decreased. The hydraulic efficiency of the optimized pump is about 59.45 per cent increasing 5.4 per cent compared with a prototype pump.

Originality/value

This study developed a new method to optimize the design parameters of aero-centrifugal pump impeller based on biharmonic equation surrogate model, which had a good agreement with experimental values within just 15 sets of the original design. The optimization results shows that the method can improve the hydraulic efficiency significantly.

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Article
Publication date: 10 November 2022

Xinxing Yin, Juan Chen, Wenxin Yu, Yuan Huang, Wenxiang Wei, Xinjie Xiang and Hao Yan

This study aims to improve the complexity of chaotic systems and the security accuracy of information encrypted transmission. Applying five-dimensional memristive Hopfield neural…

181

Abstract

Purpose

This study aims to improve the complexity of chaotic systems and the security accuracy of information encrypted transmission. Applying five-dimensional memristive Hopfield neural network (5D-HNN) to secure communication will greatly improve the confidentiality of signal transmission and greatly enhance the anticracking ability of the system.

Design/methodology/approach

Chaos masking: Chaos masking is the process of superimposing a message signal directly into a chaotic signal and masking the signal using the randomness of the chaotic output. Synchronous coupling: The coupled synchronization method first replicates the drive system to get the response system, and then adds the appropriate coupling term between the drive The synchronization error and the coupling term of the system will eventually converge to zero with time. The synchronization error and coupling term of the system will eventually converge to zero over time.

Findings

A 5D memristive neural network is obtained based on the original four-dimensional memristive neural network through the feedback control method. The system has five equations and contains infinite balance points. Compared with other systems, the 5D-HNN has rich dynamic behaviors, and the most unique feature is that it has multistable characteristics. First, its dissipation property, equilibrium point stability, bifurcation graph and Lyapunov exponent spectrum are analyzed to verify its chaotic state, and the system characteristics are more complex. Different dynamic characteristics can be obtained by adjusting the parameter k.

Originality/value

A new 5D memristive HNN is proposed and used in the secure communication

Details

Circuit World, vol. 50 no. 1
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 23 September 2022

Lidong Wu, Qingyun Wang and Kunkun Xue

Shareholder heterogeneity reflects the interactive relationship between shareholder groups of different industries and ownership types. This paper aims to discuss the impact of…

237

Abstract

Purpose

Shareholder heterogeneity reflects the interactive relationship between shareholder groups of different industries and ownership types. This paper aims to discuss the impact of shareholder heterogeneity on ambidextrous corporate innovation.

Design/methodology/approach

Combining questionnaire and database data, this study empirically analyzes the internal mechanisms of the impact of shareholder heterogeneity on ambidextrous corporate innovation.

Findings

The authors find that shareholder heterogeneity can promote ambidextrous corporate innovation and that board’s decision-making processes play an intermediary role. Specifically, shareholder industry-type heterogeneity promotes ambidextrous corporate innovation by improving procedural rationality in board’s decision-making process, and shareholder ownership-type heterogeneity promotes ambidextrous corporate innovation by improving political behavior in board’s decision-making process. The analysis of the impact degree shows that shareholder industry-type heterogeneity has a greater impact on exploitation innovation, while shareholder ownership-type heterogeneity has a greater impact on exploratory innovation. In addition, the research also shows that shareholder groups dominated by industry-type heterogeneity have an impact on corporate innovation by shaping an engaged board with higher procedural rationality and lower political behavior. Shareholder groups dominated by ownership-type heterogeneity have an impact on corporate innovation by shaping a contested board with higher political behavior and lower procedural rationality.

Originality/value

This study not only enriches the research on shareholder heterogeneity and corporate innovation in the context of transformation but also provides an analytical framework for research on board’s decision-making process.

Details

Nankai Business Review International, vol. 13 no. 4
Type: Research Article
ISSN: 2040-8749

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Article
Publication date: 7 March 2016

Xinxing Huang, Yihua Yao, Qinfen Lu, Xiaoyan Huang and Youtong Fang

In electric system of high-speed trains, neutral sections are set to balance the three-phase load. When passing neutral sections, the train should detach from the power supply for…

245

Abstract

Purpose

In electric system of high-speed trains, neutral sections are set to balance the three-phase load. When passing neutral sections, the train should detach from the power supply for a short time. To permanent magnet synchronous motors (PMSMs) traction system, the voltage of DC link will increase quickly due to the back-EMF of PMSM during this time. Although the energy consumption braking method can be adopted to consume the feedback energy. It not only wastes energy, but also causes more speed drop of the train. The paper aims to discuss these issues.

Design/methodology/approach

In order to get better performance when the train is under passing neutral section condition, a suitable control method is proposed, in which the torque command is set to zero and d-axis current order remains unchanged during passing neutral section. Based on a co-simulation model, the influences of this method on the PMSMs traction system are compared with that of traditional method, which is used in induction motors traction system. This model combines both control strategy and finite element model of motor, which can take the effects of magnetic saturation and power loss into consideration.

Findings

In PMSMs traction system, PMSMs work as generators during neutral section, and charge to DC bus, which may cause over-voltage damage. Moreover, there would be strong torque shock at the moment of power cut-off. It is finally found that, with the suitable control method, the high-speed train can pass the neutral section with less speed drop, less torque shock and little DC link voltage rise.

Originality/value

The control method proposed in this paper is easier to achieve and gets a better performance of PMSMs traction system in high-speed train compared with the traditional method. Furthermore, the co-simulation model is much closer to reality than the analytical model.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 35 no. 2
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 14 April 2014

Yujia He

Rare earths are essential materials for many high-tech industries critical to both economic development and national defense. China, the world's dominant supplier of rare earths…

854

Abstract

Purpose

Rare earths are essential materials for many high-tech industries critical to both economic development and national defense. China, the world's dominant supplier of rare earths, has recently been imposing stricter controls over its production and export. The purpose of this paper is to examine the domestic roots of the changes in China's rare earth industry production and exports in its three-decade rise to the current global monopoly.

Design/methodology/approach

This paper adopts the historical institutionalism approach to analyze the trajectory of industry and trade development. The author analyzes data collected from government whitepapers and reputed scholarly and news sources.

Findings

This paper argues that the Chinese rare earth industry has gone through three periods of development, in which the state attempted to control the market and industry through reformulating rules and institutions to achieve state goals. Domestic state institutions, combined with macroeconomic environment and state governance strategy shaped the three-decade experience of rare earth industry and trade development in China.

Originality/value

This paper builds on existing findings about Chinese state regulations to provide a novel analytical framework to analyze the role of the state in industry and trade development in the rare earth industry. The focus on a single strategic industry seldom studied in the current literature also provides ample empirical value to further scholarly understanding about this industry.

Details

International Journal of Emerging Markets, vol. 9 no. 2
Type: Research Article
ISSN: 1746-8809

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Book part
Publication date: 28 August 2015

Lowell Dittmer

China’s swift economic rise, as symbolized by the first Chinese Olympics and by surpassing Japan to become the world’s second largest economy despite the recent global financial…

Abstract

China’s swift economic rise, as symbolized by the first Chinese Olympics and by surpassing Japan to become the world’s second largest economy despite the recent global financial meltdown, has been accompanied by a transformation of Chinese foreign policy behavior. After spending the last decade emphasizing China’s “peaceful rise” or “peaceful development,” Beijing has begun to expound its policy preferences and territorial claims more forthrightly, even assertively. The purpose of this chapter will be to consider the origins, consequences, and likely future of the new Chinese foreign policy in the wake of the leadership transition at the 18th Party Congress in 2012 and the 12th National People’s Congress in 2013.

Details

Asian Leadership in Policy and Governance
Type: Book
ISBN: 978-1-78441-883-0

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Article
Publication date: 29 August 2022

Jianbin Xiong, Jinji Nie and Jiehao Li

This paper primarily aims to focus on a review of convolutional neural network (CNN)-based eye control systems. The performance of CNNs in big data has led to the development of…

356

Abstract

Purpose

This paper primarily aims to focus on a review of convolutional neural network (CNN)-based eye control systems. The performance of CNNs in big data has led to the development of eye control systems. Therefore, a review of eye control systems based on CNNs is helpful for future research.

Design/methodology/approach

In this paper, first, it covers the fundamentals of the eye control system as well as the fundamentals of CNNs. Second, the standard CNN model and the target detection model are summarized. The eye control system’s CNN gaze estimation approach and model are next described and summarized. Finally, the progress of the gaze estimation of the eye control system is discussed and anticipated.

Findings

The eye control system accomplishes the control effect using gaze estimation technology, which focuses on the features and information of the eyeball, eye movement and gaze, among other things. The traditional eye control system adopts pupil monitoring, pupil positioning, Hough algorithm and other methods. This study will focus on a CNN-based eye control system. First of all, the authors present the CNN model, which is effective in image identification, target detection and tracking. Furthermore, the CNN-based eye control system is separated into three categories: semantic information, monocular/binocular and full-face. Finally, three challenges linked to the development of an eye control system based on a CNN are discussed, along with possible solutions.

Originality/value

This research can provide theoretical and engineering basis for the eye control system platform. In addition, it also summarizes the ideas of predecessors to support the development of future research.

Details

Assembly Automation, vol. 42 no. 5
Type: Research Article
ISSN: 0144-5154

Keywords

Available. Open Access. Open Access
Article
Publication date: 12 October 2021

Zheng Li and Siying Yang

A city is a spatial carrier of innovation activities. Improving the level of urban innovation can play a significant supporting role in building an innovative country. China began…

2072

Abstract

Purpose

A city is a spatial carrier of innovation activities. Improving the level of urban innovation can play a significant supporting role in building an innovative country. China began to implement the innovative city pilot policy in 2008 and continued to expand the policy into more areas for exploring the path of innovative urban development with Chinese characteristics and improving urban innovation.

Design/methodology/approach

Based on mechanism analysis, this paper used the panel data of 269 cities from 2003 to 2016 to empirically test the effect of the pilot policy on the level of urban innovation by using different methods, such as the difference-in-differences model.

Findings

The results show that the innovative city pilot policy significantly improves the level of urban innovation. However, according to the findings of the heterogeneity analysis, the effect of the pilot policy on improving the innovation level in direct-controlled municipalities, provincial capitals and sub-provincial cities is weaker than that in ordinary cities, and the effect of the pilot policy on improving the innovation level in cities with a higher quality of science and education resources is weaker than that in cities with lower quality of science and education resources.

Originality/value

Moreover, as the level of urban innovation increases, the effect of the pilot policy on improving the level of urban innovation is an asymmetric inverted V shape, which means the effect is first strengthened and then weakened. The research also finds that the locational heterogeneity of the pilot policy for improving the level of urban innovation is not notable. In addition, the innovative city pilot policy can strengthen the government's strategic guidance, promote the concentration of talent, incentivize corporate investment and optimize the innovation environment, having a positive impact on urban innovation. Moreover, the effect of concentration of talent and the effect of corporate investment incentive are the important reasons for the pilot policy to promote the improvement of the level of urban innovation.

Details

China Political Economy, vol. 4 no. 1
Type: Research Article
ISSN: 2516-1652

Keywords

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Article
Publication date: 14 January 2025

Dorothy J. Solinger

This study aims to assess the enduring lack of citizenship for rural migrants coming to cities to work, and the extent to which there has been any progress in altering their…

2

Abstract

Purpose

This study aims to assess the enduring lack of citizenship for rural migrants coming to cities to work, and the extent to which there has been any progress in altering their status in past decades.

Design/methodology/approach

This study uses a narrative approach, relying on documentary sources. It takes a chronological approach in evaluating signs of progress but mainly tells a story of long-term continuity in the treatment of outsiders – even though they are from their own country – by urban officials and citizens.

Findings

The main finding is that the management of rural migrants in China’s cities has not fundamentally improved in the 40-plus years since they were released from the communes and permitted to come to cities to work. This is despite various pronouncements of change, most of which mattered little, if at all, in the implementation.

Originality/value

This study applies the concept of “citizenship” to what has been done and, mostly not done, for migrants over the past decades.

Details

Social Transformations in Chinese Societies, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1871-2673

Keywords

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