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The purpose of this paper is to introduce a double-stator switched reluctance machine (DS-SRM) for electric vehicles (EVs) and to propose multi-mode operations for this machine.

Analysis of flux linkage distributions and torque characteristics using finite element method (FEM). Building a dynamic simulation model based on electromagnetic characteristics, mathematical equations and mechanical motion equations of the DS-SRM drive system. The paper proposes multi-mode operations (inner-stator excitation mode, outer-stator excitation mode and double-stator excitation mode) based on motor working regions. It also conducts simulation and experimental results to verify the effectiveness of the proposed multi-mode operations strategies and control schemes.

There is almost no electromagnetic coupling between the inner and outer stators due to the specially designed rotor structure and optimized windings polarity configuration. Analysis of flux linkage distributions and torque characteristics verified the independence of inner and outer stators. Proposal of multi-mode operations and corresponding control rules achieved the smooth switching between different modes.

The paper introduced the DS-SRM for EVs and proposed multi-mode operations, along with control rules, to optimize its performance. The specially designed rotor structure, optimized winding polarity configuration, and the proposed multi-mode operations contribute to the originality of the research.

The purpose of this paper is to examine whether the shareholding of the largest shareholder and other large shareholders could exert a good stimulating effect within a firm's corporate governance structure and what impact the balance of power among large shareholders could have on top management turnover.

This paper has investigated 787 firms publicly listed in the Shanghai Stock Exchange and checked the relation between power balance of firms' block shareholders and their top management turnover.

The paper's empirical results show that there is a U‐shaped relationship between the proportions of shareholding of a firm's largest shareholder and its top management turnover, that is, the controlling shareholder could impose either negative or positive effect for different types of equity ownership. We also find that the proportion of shares held by other block shareholders is significantly and positively related to the turnover of management and the monitoring effect of other large shareholders is strong. Furthermore, duality of chairman and CEO shows a significant negative effect on firms's top management turnover.

The paper usefully shows that under the institutional background of relatively weak legal protection for medium and small investors in China, centralized shareholding by large shareholders in listed firms, or the so‐called mechanism of power balance among block shareholders, has the ability to effectively supervise and restrain the corporate governance of a firm, replace ineffective managers and thus improve its whole management performance.

This study aims to investigate the relationship between person-role conflict, psychological capital and emotional exhaustion. Specifically, the research explores how person-role conflict magnified due to daily contact with COVID-19 carriers leads doctors and nurses to experience emotional exhaustion. Moreover, psychological capital function as an explanatory mechanism between stressor strain relationships has also been tested.

The study results are based on three months of lagged data conducted from the sample of 347 frontline physicians and nurses who provide treatment and care to infected people. To test direct, indirect and total effect, the author's used PROCESS Macro.

The results suggested that person-role conflict reduces state-like psychological capital and increases emotional exhaustion through reduced psychological capital. Results aligned with the model's expectations in that psychological capital mediated the relationship between person-role conflict and emotional exhaustion, and the mediation was partial.

This paper is the first one that tested the link between person-role conflict and emotional exhaustion. Moreover, up till now, no study has examined the mediating role of psychological capital in the relationship between person-role conflict and emotional exhaustion. Finally, in the context of the contagion outbreak, this is the preliminary effort that validated the resource loss cycle principle of conservation of resource theory.

The purpose of this paper is to calculate and measure transients for two different constructions of electrodynamic accelerators (ironless and iron-core) supplied by a three-section power system (three capacitor banks). The optimization of power supply parameters (switch-on times and capacitances of individual sections) in terms of system efficiency has been carried out.

Calculations have been carried out using a field-circuit model. For three-dimensional magnetostatic analysis, the Maxwell software and finite element method (FEM) were used, while for circuit model, the Matlab/Simulink software was implemented. For optimization of the supply system parameters, the genetic algorithm was used. The mathematical models were verified experimentally by using the original laboratory stand.

The efficiency of the system is much higher in case of iron-core accelerator. In both cases, the results obtained for optimized supply settings are only slightly better than those obtained by simultaneously switching on the thyristors and for symmetrical capacity division.

Due to the presented field-circuit model, eddy currents in rails have been neglected. In the field model, there was no possibility to combine current flow calculations with moving of the projectile.

Using the presented filed-circuit model, both electrical and mechanical transients could be calculated with sufficient precision. Thus, it could be used in the optimization of supply system. The solution time is low compared with the solution time of the transient field model.

An uncertain product demand in online retailing leads to loss of opportunity cost and customer dissatisfaction due to instances of product unavailability. On the other hand, when e-retailers store excessive inventory of durable goods to fulfill uncertain demand, it results in significant inventory holding and obsolescence cost. In view of such overstocking/understocking situations, this study attempts to mitigate online demand risk by exploring novel e-retailing approaches considering the trade-offs between opportunity cost/customer dissatisfaction and inventory holding/obsolescence cost.

Four e-retailing approaches are introduced to mitigate uncertain demand and minimize the economic losses to e-retailer. Using three months of purchased history data of online consumers for durable goods, four proposed approaches are tested by developing product attribute based algorithm to calculate the economic loss to the e-retailer.

Mixed e-retailing method of selling unavailable products from collaborative e-retail partner and alternative product's suggestion from own e-retailing method is found to be best for mitigating uncertain demand as well as limiting customer dissatisfaction.

Limited numbers of risk factor have been considered in this study. In the future, others risk factors like fraudulent order of high demand products, long delivery time window risk, damage and return risk of popular products can be incorporated and handled to reduce the economic loss.

The analysis can minimize the economic losses to an e-retailer and also can maximize the profit of collaborative e-retailing partner.

The study proposes a retailer to retailer collaboration approach without sharing the forecasted products' demand information.

The purpose of this paper is to attempt to realize the optimization of cascading failure process of urban transit network based on Load‐Capacity model, for better evaluating and improving the operation of transit network.

Robustness is an essential index of stability performance for urban transit systems. In this paper, firstly, the static robustness of transit networks is analyzed based on the complex networks theory. Aiming at random and intentional attack, a concrete algorithm process is proposed on the basis of Dijstra algorithm. Then, the dynamic robustness of the networks, namely cascading failure, is analyzed, and the algorithm process is presented based on the Load‐Capacity model. Finally, the space‐of‐stations is adopted to build the network topology of Foshan transit network, and then the simulation analyses of static and dynamic robustness are realized.

Results show that transit network is robust to random attack when considering static robustness, but somewhat vulnerable to intentional attack. For dynamic robustness analysis, a large‐scale cascade of transit network may be triggered when the tolerance parameter α is less than a value, so that the robustness of transit network can be improved through some reasonable measures.

The results of this study provide useful information for urban transit network robustness optimization.

An effective method for analyzing the static and dynamic robustness of transit network is provided in this paper.

The purpose of this study is to provide an in-depth understanding about the indoor-orbital electrical inspection robot, which is useful for motivating the further investigation on the inspection of electrical equipment. Currently, electric energy has a strong correlation with the economic development of the country. Intelligent substations play an important role in the transmission and distribution of the electricity; the maintenance of the substation has attracted intensive attention due to the requirement of reliability and safety. The indoor-orbital electrical inspection robot has increasingly become the main tool to realize the unmanned. Hence, a systematic review is conducted systematically reviewing the current technical status of the indoor-orbital electrical inspection robot and discuss the existed problems.

In this paper, the most essential achievements in the field of indoor-orbital electrical inspection robots were reported to present the current status, and the mechanical structures and key inspective technologies were also discussed.

Four recommendations are provided from the analyzed review, which have made constructive comments on the overall structural design, functionality, intelligence and future development direction of the indoor-orbital electrical inspection robot, respectively.

To the best of the authors’ knowledge, this is the first systematic review study on indoor-orbital electrical inspection robots; it fills the theoretical gap and proffers design ideas and directions for the development of the indoor-orbital electrical inspection robot.