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The purpose of this paper is to establish an intelligent framework to generate the data representatives in snapshot simulation in order to construct the online reduced-order model based on the generated data information. It could greatly reduce the computational time in snapshot simulation and accelerate the computational efficiency in the real-time computation of reduced-order modeling.

The snapshot simulation, which generates the data to construct reduced-order models (ROMs), usually is computationally demanding. In order to accelerate the snapshot generation, this paper presents a discrete element interpolaiton method (DEIM)-embedded hybrid simulation approach, in which the entire snapshot simulation is partitioned into multiple intervals of equal length. One of the three models: the full order model (FOM), local ROM, or local ROM-DEIM which represents a hierarchy of model approximations, fidelities and computational costs, will be adopted in each interval.

The outcome of the proposed snapshot simulation is an efficient ROM-DEIM applicable to various online simulations. Compared with the traditional FOM and the hybrid method without DEIM, the proposed method is able to accelerate the snapshot simulation by 54.4%–63.91% and 10.5%–27.85%, respectively. In the online simulation, ROM-DEIM only takes 4.81%–8.56% of the computational time of FOM, while preserving excellent accuracy (with relative error <1%).

1. A DEIM-embedded hybrid snapshot simulation methodology is proposed to accelerate snapshot data generation and reduced-order model (ROM)-DEIM development. 2. The simulation alternates among FOM, ROM and ROM-DEIM to adaptively generate snapshot data of salient subspace representation while minimizing computational load. 3. The DEIM-embedded hybrid snapshot approach demonstrates excellent accuracy (<1% error) and computational efficiency in both online snapshot simulation and online ROM-DEIM verification simulation.

The primary goal of this paper is to investigate the relationship between stock market liquidity and firm dividend policy within a market implementing the tax imputation system. The main aim is to understand how the tax imputation system influences the relationship between firm dividend policy and stock market liquidity within a cross-sectional framework.

This paper investigates the relationship between stock market liquidity and the dividend payout policy under the full tax imputation system in the Australian market. This study uses the Generalized Least Squares regressions with firm- and year-fixed effects.

In contrast to the negative relationship between the liquidity of common shares and the firms' dividends documented in countries with the double tax system, the study reveals that in Australia, the dividend payout ratios are positively associated with liquidity after controlling for various explanatory variables with both the contemporaneous and lagged time periods. Such a finding is robust to the use of alternative liquidity proxies and to the sub-period tests and remains during the COVID-19 pandemic period.

The insights derived from this study have significant implications for various stakeholders within the economy. The findings provide regulators with valuable insights to conduct a more holistic assessment of how the tax system impacts the economy, especially concerning the dividend choices of firms. Within the context of a full tax imputation system, investors can make investment decisions without factoring in the taxation impact. Simultaneously, firms can be relieved of concerns about losing investors who prioritize liquidity, particularly when a high dividend payout might not align optimally with their financial strategy.

This study contributes to the literature by extending the literature on the tax clientele effects on dividend policy, providing evidence that the tax imputation system can moderate the impact of liquidity on dividend policy. This study examines the impact of the dividend tax imputation system on the substitution effect between dividends and liquidity.

The existence of clearance in joints of positioning mechanism is inevitable and the movements of the real mechanism are deflected from the ideal mechanism due to the clearances. The purpose of this paper is to investigate the effects of clearance on the dynamic characteristics of dual-axis positioning mechanism of a satellite antenna.

The dynamics analysis of dual-axis positioning mechanism with clearance are investigated using a computational approach based on virtual prototyping technology. The contact model in joint clearance is established by using a hybrid nonlinear continuous contact force model and the friction effect is considered by using a modified Coulomb friction model. Then the numerical simulation of dual-axis positioning mechanism with joint clearance is carried out and four case studies are implemented for different clearance sizes.

Clearance leads to degradation of the dynamic performance of the system. The existence of clearance causes impact dynamic loads, and influences the motion accuracy and stability of the dual-axis positioning mechanism. Larger clearance induces higher frequency shakes and larger shake amplitudes, which will deteriorate positioning accuracy.

Providing an effective and practical method to analyze dynamic characteristics of dual-axis positioning mechanism of satellite antenna with joint clearance and describing the dynamic characteristics of the dual-axis positioning system more realistically, which improves the engineering application.

The paper is the basis of mechanism design, precision analysis and robust control system design of dual-axis positioning mechanism of satellite antenna.

The transfer of technology from the foreign partner to the domestic partner has been a problem for international joint ventures throughout the world, but particularly in China. Because of the nature of organisational learning, especially in its tacit forms, such transfers can occur quite subtly without the foreign partner realising what has transpired until it is too late. The problem is complicated by the fact that technology is short‐lived and must be exploited within narrow time frames, the fact that the Chinese partner’s primary interest is in acquiring the foreign partner’s technology, and the fact that the foreign partner typically shows little interest in obtaining the Chinese partner’s unique non‐technical knowledge as an offset. This article attempts to show how technology transfers can be controlled in the first place and how the foreign partner’s competitive advantage can be preserved by acquiring the domestic partner’s unique knowledge of host country circumstances.

The various levels of research support undergirding effective practices are outlined. Evidence supporting specific programming, service delivery models, and curricular interventions, and a subset of research-based classroom strategies for talented learners is reviewed. Trends and innovations for effective practices in the future are suggested.

The research on analysis on the new type and countermeasures of credit card fraud in mainland China mainly aims to take a comprehensive approach to fight against fraud and place a strong emphasis on fraud prevention conducted in the best interests of financial institutions, card holders, merchants and law enforcement authorities to keep fraud from happening in the first place and to give more information on anti‐credit card fraud best practices.

In this paper, the authors analyzed the relevant definitions in Chinese statutes and ordinances, the new types of credit card fraud which have occurred in China in recent years and what would be the effective countermeasures to fight against and prevent them. It was completed based on many references and extensive survey in police organs in China.

With the credit card more and more widely used in mainland China as a most prevalent means of payment and settlement, credit card crime has been rapidly increasing to accompany this, with more fraudulent and disguised features which add to the complexity and difficulties of the work on its combating and prevention.

Hopefully, it explores for the best to detect and combat credit card fraud crimes and can contribute to the healthy growth of bankcard industries, meanwhile calling for the involvement of the concerted efforts of the banks, merchants, the public and the law enforcement personnel.

This study aims to improve the passenger accessibility of passenger demands in the end-of-operation period.

A mixed integer nonlinear programming model for last train timetable optimization of the metro was proposed considering the constraints such as the maximum headway, the minimum headway and the latest end-of-operation time. The objective of the model is to maximize the number of reachable passengers in the end-of-operation period. A solution method based on a preset train service is proposed, which significantly reduces the variables of deciding train services in the original model and reformulates it into a mixed integer linear programming model.

The results of the case study of Wuhan Metro show that the solution method can obtain high-quality solutions in a shorter time; and the shorter the time interval of passenger flow data, the more obvious the advantage of solution speed; after optimization, the number of passengers reaching the destination among the passengers who need to take the last train during the end-of-operation period can be increased by 10%.

Existing research results only consider the passengers who take the last train. Compared with previous research, considering the overall passenger demand during the end-of-operation period can make more passengers arrive at their destination. Appropriately delaying the end-of-operation time can increase the proportion of passengers who can reach the destination in the metro network, but due to the decrease in passenger demand, postponing the end-of-operation time has a bottleneck in increasing the proportion of passengers who can reach the destination.

This study aims to examine how the initial ambiguity of COVID-19 contributed to tourists' intentions for visiting a once-viral outbreak site in the future.

The present study (N = 248) used partial least-squares structural equation modeling (PLS-SEM) to examine whether perceptions of ambiguity and mismanagement of COVID-19 are indirectly related to intentions to travel to Wuhan in a post-pandemic world through perceptions of risk and tourism value. Further, whether the model effects differed as a function of individual safety orientation was examined.

Perceptions of COVID-19 risk and tourism value serially mediated the effects of perceived COVID-19 ambiguity on post-pandemic travel intentions. Safety orientation did not moderate any paths. Perceived risk was a negative direct correlate of post-pandemic travel intentions.

The current study's strength is rooted in its specific targeting of post-pandemic travel intentions to Wuhan—the first city to experience a widescale outbreak of COVID-19 and subsequent international stigma—compared to general travel inclinations.

Prior to the onset of the COVID-19 pandemic, women did nearly three-quarters of the world’s unpaid work. As institutional supports, including in-person school and community-based care for children, the elderly, and the disabled vanished early in the pandemic, many women’s caregiving responsibilities increased. In some cases, opportunities for paid employment disappeared due to layoffs and furloughs, while in others, paid work was no longer possible without access to the missing institutional supports. Either way, access to needed supports – financial, practical, and social – was diminished. The lapse of needed supports also had severe impacts on subgroups of women, including pregnant and post-partum women. A range of considerations – vaccine safety, social interaction and infection risk, disease severity – have posed serious challenges for pregnant and post-partum women. Across the board, women’s need for continuous access to better social, financial, and practical supports at home, in the community, and in the workplace was made even more evident by the COVID-19 pandemic.

Because of the specific structure and working mechanism, piston speed is only half of its shaft, which causes severally friction between piston and cylinder. Therefore, the main purpose of this paper is to investigate the friction and wear characteristics of the incomplete spherical piston in spherical pump comprehensively. Finally, to search the low-friction and wear-resistance structural pattern of the piston, and enhance the durability of spherical pump.

The non-linear frictional moment model for incomplete spherical piston in spherical pump was derivated quantificationally. Parameter sensitivity analyses were conducted to find the low-friction structural pattern of the piston. The theoretical wear model of piston–cylinder pair is proposed as well.

To reduce the frictional moment between incomplete piston and cylinder, the optimised diameter ratio between piston pin and piston should be 0.12 based on the parameter sensitivity analyses. The maximum frictional moment is approximately 2.5 times of the minimum. The total efficiency should be considered synthetically based on the thickness of specific working medium.

The proposed non-linear frictional moment model offers the quantitative estimations. Parameter sensitivity analyses were conducted to find the low-friction structural pattern of the piston. The wear behaviours of the piston and cylinder were analysed to investigate the wear characteristics of the piston.