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Owing to the excellent performance, giant magnetostrictive materials (GMMs) are widely used in many engineering fields. The dynamic Jiles–Atherton (J-A) model, derived from physical mechanism, is often used to describe the hysteresis characteristics of GMM. However, this model, despite cited by many different literature studies, seems not to possess unique expressions, which may cause great trouble to the subsequent application. This paper aims to provide the rational expressions of the dynamic J-A model and propose a numerical computation scheme to obtain the model results with high accuracy and fast speed.

This paper analyzes different published papers and provides a reasonable form of the dynamic J-A model based on functional properties and physical explanations. Then, a numerical computation scheme, combining the Newton method and the explicit Adams method, is designed to solve the modified model. In addition, the error source and transmission path of the numerical solution are investigated, and the influence of model parameters on the calculation error is explored. Finally, some attempts are made to study the influence of numerical scheme parameters on the accuracy and time of the computation process. Subsequently, an optimization procedure is proposed.

A rational form of the dynamic J-A model is concluded in this paper. Using the proposed numerical calculation scheme, the maximum calculation error, while computing the modified model, can remain below 2 A/m under different model parameter combinations, and the computation time is always less than 0.5 s. After optimization, the calculation speed can be enhanced with the computation accuracy guaranteed.

To the best of the authors’ knowledge, this paper is the first one trying to provide a rational form of the dynamic J-A model among different citations. No other research studies focus on designing a detailed computation scheme targeting the fast and accurate calculation of this model as well. And the performance of the proposed calculation method is validated in different conditions.

Robotic arms’ interactions with the external environment are growing more intricate, demanding higher control precision. This study aims to enhance control precision by establishing a dynamic model through the identification of the dynamic parameters of a self-designed robotic arm.

This study proposes an improved particle swarm optimization (IPSO) method for parameter identification, which comprehensively improves particle initialization diversity, dynamic adjustment of inertia weight, dynamic adjustment of local and global learning factors and global search capabilities. To reduce the number of particles and improve identification accuracy, a step-by-step dynamic parameter identification method was also proposed. Simultaneously, to fully unleash the dynamic characteristics of a robotic arm, and satisfy boundary conditions, a combination of high-order differentiable natural exponential functions and traditional Fourier series is used to develop an excitation trajectory. Finally, an arbitrary verification trajectory was planned using the IPSO to verify the accuracy of the dynamical parameter identification.

Experiments conducted on a self-designed robotic arm validate the proposed parameter identification method. By comparing it with IPSO1, IPSO2, IPSOd and least-square algorithms using the criteria of torque error and root mean square for each joint, the superiority of the IPSO algorithm in parameter identification becomes evident. In this case, the dynamic parameter results of each link are significantly improved.

A new parameter identification model was proposed and validated. Based on the experimental results, the stability of the identification results was improved, providing more accurate parameter identification for further applications.

The purpose of this study is to examine whether the institutional environment influences auditor reporting.

This study employs China's anti-corruption campaign as an exogenous shock to its institutional environment and compares auditors' issuance of modified audit opinions (MAOs) to small-profit clients before and during the campaign.

This study documents that small-profit clients were more likely to receive MAOs during the anti-corruption campaign period than before, indicating that auditors issued more conservative audit opinions to small-profit clients because of the anti-corruption campaign. Additionally, this study finds that increased auditor conservatism was more pronounced for auditors of large clients.

This study suggests that a weak institutional environment adversely affects auditor conservatism. This offers valuable insights for governments and regulators to improve the audit environment and for audit firms to enhance auditors' integrity and independence.

This study contributes to the research on institutional environments and auditing by observing a unique exogenous event.

The purpose of this study is to examine whether independent directors' financial expertise affects the use of private information in setting bank chief executive officer (CEO) bonuses.

The association between future firm performance and bank CEO bonuses is used to measure the incorporation of private information into bonuses. Both level and change specifications are employed to test the effect of independent directors' financial expertise on the use of private information in setting CEO bonuses.

It is found that future firm performance is more positively associated with bank CEO bonuses for banks with a higher proportion of financial experts among independent directors than for other banks. The findings suggest that independent directors with financial expertise can more effectively use private information in setting bank CEO bonuses.

Research on independent directors' role in the use of private information in setting compensation is valuable for understanding how corporate governance can enhance the efficiency of CEO compensation contracts. This study indicates that financial experts on the bank board play an important role in this regard.

The purpose of this study is to examine whether firm-specific litigation risk affects independent director conservatism in the oversight of financial reporting.

This study considers the enactment of Sarbanes–Oxley Act and the main US stock exchanges' corresponding corporate governance regulations in 2002–2003 as an exogenous shock event to increase board independence. OLS regressions with fixed effects are conducted to test the hypothesis.

Changes in discretionary accruals from the pre-event year (2001) to the post-event year (2004) are more negatively associated with an exogenous increase in board independence for firms with high litigation risk than for firms with low litigation risk.

The results suggest that independent directors are more conservative in overseeing financial reporting when they face higher litigation risk, consistent with the notion that they are still concerned about liability risk although they seldom have to pay damages or legal fees out of their own pockets.

The purpose of this study is to examine whether the COVID-19 pandemic has affected earnings management and the value relevance of earnings in the USA.

Discretionary accruals, the explanatory power and slope coefficient of earnings are compared between 2019 (prepandemic year) and 2020 (pandemic year). Univariate and regression analyses are performed.

There was a significant decline in discretionary accruals from 2019 to 2020, suggesting that firms engaged in more income-decreasing earnings management to take a big bath in reporting earnings in the pandemic year. Meanwhile, the explanatory power and slope coefficient of earnings both were lower in 2020 than in 2019, consistent with the notion that the pandemic has impaired the value relevance of earnings.

This study explores the consequences of the pandemic from accounting perspective. It also enriches accounting research on economic crises.

The purpose of this study is to examines whether clients’ share prices responded to three events, including the Securities and Exchange Commission (SEC) launch of administrative proceedings against five Chinese accounting firms on December 3, 2012, for their failure to hand over audit work papers due to conflict of jurisdiction; the issuance of SEC Administrative Law Judge Elliot’s ruling on January 22, 2014; and the settlement of the administrative proceedings on February 6, 2015.

This study uses the Schipper and Thompson approach.

It is found that share prices responded negatively around December 3, 2012, for USA-listed Chinese companies who were audited by Chinese auditors.

This study provides evidence on how share prices reacted to SEC enforcement actions against an affair of non-audit failure.

The purpose of this study is to investigate the effectiveness of independent audit committees in constraining real earnings management. This study examines the relationships between audit committee characteristics and real activities manipulation.

US firms with stronger incentives to undertake real earnings management are selected as a sample. Regressions are run for the empirical analyses.

It is found that audit committee members' additional directorships are positively associated with real earnings management measured by abnormal cash flows from operations, abnormal discretionary expenses and abnormal production costs, suggesting that audit committees with high additional directorships are less effective in constraining real earnings management. The findings are consistent with the notion that audit committee members' busyness impairs their monitoring effectiveness.

This study extends the extant research on audit committees' oversight of real earnings management by using refined research design and updated data. This study also provides further evidence on how audit committee members' additional directorships affect their ability to oversee both accrual and real earnings management.

The purpose of this paper is to examine whether high analyst coverage increases or decreases accounting conservatism.

Sample firms were selected from the Compustat and I/B/E/S databases for years 1989‐2006. The authors used both accrual‐based and market‐value‐based measures of accounting conservatism, also the extent to which negative cash flow from operations is more timely recognized via accruals than positive cash flow from operations to measure accounting conservatism. The regression analyses are conducted to test the hypotheses.

Strong evidence was found that analyst coverage is positively associated with accounting conservatism. The results suggest that firms choose more conservative accounting methods when they are followed by more analysts than when they are followed by fewer analysts. The results are robust to a battery of sensitivity analyses.

This paper sheds light on how analyst coverage affects firms' accounting choices and extends the limited research on the monitoring role of analyst coverage. The findings are consistent with the notion that analyst coverage plays an important corporate governance role in the financial reporting process. This paper also adds to the literature on the economic determinants of accounting conservatism, and provides some implications for practitioners.

The purpose of this paper is to examine whether the type of ultimate controllers (i.e. private vs state) affects corporate disclosure quality and whether the relationship between the type of ultimate controllers and corporate disclosure quality is moderated by the separation of ownership and control.

This study employs the data of 405 Chinese listed firms in 2005. Annual reports were reviewed to collect the data including the type of ultimate owners, cash‐flow rights, and control rights; and the ratings of corporate disclosure quality were obtained from the Shenzhen Stock Exchange website. Ordered logistic regression tested the hypotheses.

It was found that corporate disclosure quality is lower for firms ultimately controlled by individuals than for firms ultimately controlled by the state. Also, the negative effect of private ultimate ownership on corporate disclosure quality is stronger for firms with high deviation of cash‐flow rights and control rights.

These findings suggest that privatizing state‐owned companies may increase the expropriation of minority shareholders by controlling shareholders if the privatization does not reduce the separation of cash‐flow rights from control rights. Thus, it may be necessary to strengthen the governance role of minority shareholders and constrain the divergence between cash‐flow rights and control rights of the ultimate owners when state‐owned companies are privatized.

This study contributes to the literature on the expropriation of minority shareholders by examining the main effect of the type of ultimate controllers and the interactive effect of ultimate ownership type and the divergence of ownership and control on corporate disclosure quality.