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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.

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.

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.

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.

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.

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.

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.

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

The purpose of this paper is to make objective descriptions on various money‐laundering techniques and to put forward countermeasures in order to combat money laundering more effectively and efficiently.

This paper based on 20 simplified money‐laundering cases, describes various money‐laundering techniques, analyses the reasons why these methods prevail, and points out the future efforts to be made in the fight against money laundering.

As usual, the ways of money laundering include cash smuggling, making use of banks or insurance company, or making use of shell‐company or front‐company. Nowadays, criminals also turn to real estate, lottery, international trade, offshore company to launder money. Sometimes lawyers, accountants are exploited by money launderers. With the wide use of electronic money and internet, criminals prefer to launder money through non‐face to face transactions. The fight against money laundering is the fight between justice and evil. It is of great importance to pierce the secret veil of money laundering so that we can combat money laundering more effectively and efficiently.

This paper prevents a comprehensive description of, and comments on, various money‐laundering techniques and future efforts to be made in the fight against money laundering, which would be beneficial to policy makers, enforcement authorities, and judicial professionals.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

This paper analyzes and discusses the fundamental role of new urbanization in the construction of a new development pattern based on the specific practice of China’s new urbanization construction, combining the classical Marxist ideas in urbanization and the theory of the industrial capital circulation, and proposes to remove blockages in the domestic and international circulations through developing new urbanization and construct a new development pattern with the domestic circulation as the mainstay and the domestic and international circulations promoting each other, thereby achieving high-quality national economic operation.

Based on the theory of industrial capital circulation, this paper elucidates the general process of domestic and international economic circulations, critically examines the bottlenecks and challenges in economic circulation, and emphasizes the mechanisms through which new urbanization contributes to the formation of a new development pattern.

The people-centered new urbanization can effectively release domestic demand, optimize investment supply, and stabilize market participants’ expectations, linking the national economic circulation from production to consumption and alleviating supply and demand mismatches, which has a fundamental role in building the new development pattern.

We should focus on creating a comprehensive domestic demand system based on counties while fostering a unified domestic market led by urban clusters and metropolitan areas to stabilize and enhance the expectations of both domestic and international market participants.

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.

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

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.

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.

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.

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.

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.

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