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This paper aims to solve the uncertainty problem of hypersonic vehicle tracking control; an adaptive terminal sliding mode control (TSMC) method based on extended state observer (ESO) is proposed. The combination of adaptive techniques, TSMC and ESO offers an effective approach for managing uncertain systems.

The dynamic model of a hypersonic vehicle is transformed into two control-oriented subsystems. The control system design incorporates an adaptive technique, an ESO and a TSMC. The ESO estimates the primary uncertainties, while the adaptive technique determines the upper limit of secondary uncertainties. These estimates are used for the design of the TSMC law. In addition, the filter is used to generate the reference trajectory to improve the dynamic performance of the system. The stability of the closed-loop system is proved by the Lyapunov stability theory.

A robust control system for hypersonic vehicles is developed with guaranteed stability and strong adaptability to various uncertainties such as parameter variations, external disturbances and actuator faults. Furthermore, the proposed system demonstrates enhanced dynamic performance compared to observer-based sliding mode control. Specifically, for the velocity and altitude tracking control, the settling time of the proposed sliding mode control is approximately 100 s and 70 s shorter than that of the observer-based sliding mode control, respectively.

Different from the single equivalent treatment, various uncertainties here are classified and treated with different strategies, which improves the disturbance rejection ability of the control system. This ability is of great significance for enhancing the autonomy, adaptability and reliability of hypersonic vehicles in extreme environments.

The purpose of this paper is to explore some specific, current social phenomena in China that may influence consumers’ ethical beliefs and practices, focusing on how some top-down, social and political changes could shape consumer behavior that needs to be understood in the Chinese context.

Extensive literature was critically reviewed to explore recent macro-societal reforms in China and their impact on consumers’ (un)ethical practices.

The authors lay out how China, a government-led society, underwent a series of political reforms resulting in demographic shifts that differentiate it from its western, industrialized counterparts. The authors connect these societal changes with Chinese characteristics to consumers’ ethical evaluations, forming a new angle to understand consumer ethics in China. The authors also draw on two empirical examples to illustrate the argument.

While consumer ethics are often explained by either cultural factors or individual variations, the authors discuss how one’s ethical practice is shaped by one’s social position, which is a product of national-level public policy. The discussions have ramifications for the study of consumers’ social class and ethical practices because they take into account the elusive social positions and ambiguous social class consciousness of the Chinese population that have resulted from social mobility. The discussions may give practitioners a better understanding of the ethical rationale behind consumers’ changing lifestyles especially in the Chinese context.

For any developing countries in the 20th century, there exists a problem of how to choose the economic development route – socialist or capitalist; which means how to compare different social and economic benefits and make different value judgements in economic development. Socialism is not a pure political and ideological question, certainly not just a political question. It is a way for developing countries, particularly large agricultural countries, to realise their industrialisation and modern commercial economy. Essentially, it is a focus of development economics. For economically backward countries the aim of socialism is not to fight against the capitalist world, but first to develop their own economy. Socialist public ownership connected with the stage of economic development involves inner contradictions in its own development from the very beginning. We cannot make socialist public ownership perfect without overcoming those contradictions. Public ownership cannot improve social productivity without coming across its own historical limitation. Economic reforms now being practised in China are an effort to improve socialist public ownership: to reform traditional forms of public ownership which have not satisfied the development of productivity. Socialism and public ownership are not features for economically backward countries to flaunt. Neither are they historical trends. They are a way to get rid of poverty, and to realise a modern commercial economy, a way different from the development route of capitalism. There are historical necessity and economic rationality for that kind of socialist public ownership connected with economic development of backward countries. And, of course, socialist public ownership has its own inner contradictions and historical limitations, just like any other kind of ownership in history. It changes and develops continually. Socialist public ownership needs to improve itself, to realise its own development and evolution, and finally to make assets of public ownership the social capital satisfying the demand of highly socialised productivity.

The purpose of the study reported in this paper is to synthesis curcumin, which was reported to possess broad pharmacological effects and excellent dyeing properties, via Claisen-Schmidt condensation reaction catalysed by an efficient and green solid base catalyst, KF/Al₂O₃.

A series of catalysts with different KF loadings and varying calcination temperatures had been prepared, characterised by Brunauer–Emmett–Taller surface area, temperature-programmed desorption with CO₂ using infrared spectroscopy, X-ray powder diffraction and X-ray photoelectron spectroscopy, and tested in the Claisen–Schmidt condensation reaction. The effects of different reaction parameters such as temperature, the amount of catalyst, reactant ratio and time on the synthesis of curcumin were examined. The possibility of recycling the catalyst was also investigated in detail. Moreover, the reaction mechanism and the role of KF/Al₂O₃ in the synthetic process were discussed.

The study provides an efficient and green solid base catalyst, KF/Al₂O₃, and 64.3 per cent yield of curcumin was obtained under the optimum reaction conditions. Experimental results indicate that the third reused catalyst could retain part of the catalytic activity, and the regenerated one could be reused with reasonable catalytic activity. Besides, K₃AlF₆ was proposed as the active site of the catalyst for the reaction by the analysis of the characterization results of KF/Al₂O₃.

KF/Al₂O₃ was found to be an efficient catalyst for catalytic synthesis of curcumin and could be easily recycled several times. This information may be useful for further research and practical applications of curcumin.

This study aims to investigate the several parameters in wafer-level packaging (WLP) to find the most critical factor impacting the thermal fatigue life, such as the height of copper post, the height of solder bump, the thickness of chip. The FEA results indicate the height of solder bumps is the most important factor in the whole structure.

The copper post bumps with 65 µm pitch are proposed to investigate the thermal-mechanical performance of WLP. The thermal cycle simulation is used to evaluate the reliability of WLP by using finite element analysis (FEA). Taguchi method is adopted to obtain the sensitivity of parameters of three-dimension finite element model, for an optimized configuration.

It can be found that the optimal design has increased thermal fatigue life by 147% compared with the original one.

It is concluded that the finite element simulation results show outstanding thermal-mechanical performances of the proposed 65 µm pitch copper post bumps of WLP, including low plastic strain, high thermal fatigue life, which are desired for mobile device.

To improve the robustness of missile control system and reduce the error, a missile attitude adaptive control method based on active disturbance rejection control technology (ADRC) and BP neural network is innovatively proposed.

ADRC improves the performance of the missile control system by estimating and eliminating the total disturbance of the system. BP neural network adjusts the parameters of ADRC controller according to the state of the system to realize adaptive control. Based on the control system and missile dynamics model, the convergence analysis of the extended state observer and the stability analysis of the closed-loop system after embedding BP neural network are given.

The simulation results show that the adaptive control method can adjust the coefficient of error feedback rate according to the system input, output and error change rate, which accelerates the response speed of missile attitude angle and reduces the attitude angle error.

BP–ADRC further improves the robustness and environmental adaptability of the missile control system. The BP–ADRC control method proposed in this paper is proved feasible.

Different from the traditional ADRC, the BP–ADRC feedback signal proposed in this paper uses the output signal and its rate of the closed-loop system instead of the system state quantity estimated by extended state observer (ESO). This innovative method combined with BP neural network can make the system output meet the requirements when ESO has errors in the estimation of missile dynamics model.

This paper aims to investigate the association between International Financial Reporting Standards (IFRS) effort due to higher levels of material adjustments and audit fees. In addition, this paper tests whether these associations differ between industry specialist auditors and non-specialist auditors.

The authors measure IFRS effort by using differences between local GAAP and IFRS. More specifically, they measure the differences in the balances of accounts that are prepared under IFRS as opposed to the previously used Australian Accounting Standards Board (AASB) standards. They posit that higher material adjustments and more risk to fair presentation of financial statements require additional accounting and auditing effort (“IFRS effort”).

The authors find that audit fees are higher when accounting standards are more material and complex at an aggregate level. Nevertheless, not all standards are equally complex and/or material and not all individual standards contribute to higher audit fees. In addition, the results show that the positive association between IFRS effort and audit fees is more pronounced when firms are audited by city-level industry specialists than by non-industry specialists.

Overall, the results are consistent with the prediction of increasing audit fees for firms requiring higher levels of IFRS effort compared to firms requiring lower levels of IFRS effort. The results contribute to the understanding that not all IFRS are equally complex and, thereby, the standards require different levels of auditor effort. Isolating specific standards based on materiality/risk levels is informative to standard setters for standard setting, standard implementation and post-implementation review of standards.

The purpose of this research is to understand whether an organization knows if it is ready to respond to a disaster and whether it has the capabilities to deliver relief. Our initial motivation was to identify unique resources possessed by the United States Navy (USN) and United States Marine Corps (USMC) due to their unique and critical capabilities for humanitarian operations. The recent frequency of disasters around the world suggests these events will continue to create demand for relief capabilities. For this reason we need to understand readiness metrics not just for USN and USMC but for humanitarian organizations (Hos) in general.

We survey relevant literature for understanding how HOs define and develop readiness metrics and associated factors. We studied documents including peer-reviewed scholarly articles, government documents, white papers, research papers and Department of Defense (DoD) briefings. We study literature that is significantly written for DoD, one, the vast experience of USN and USMC and two, the lessons learned have been documented. The literature offers substantial information on what readiness means and why it is important. This documented information is critical because it is known to the researchers in humanitarian operations that data is hard to come by.

The framework for readiness proposed at the end of this article is context the emergency responder probably uses in an informal fashion. The validation of readiness framework, we find exists in the supporting literature we review.

The understanding of readiness metrics for humanitarian operations for the organizations we study may offer insight into other HOs. The insights we gain may not be pivotal or counterintuitive to the conclusions based on commonsense. However, they are supported by the literature review. We formalize the concept based on conclusions of a set of diverse set of researchers and practitioners such as academic scholars, DoD personnel and government officials involved in humanitarian missions, USAID representatives that are repeatedly tasked for being ready, military and government officers from host and foreign countries and many more.

The purpose of this paper is to introduce error ellipse into the bootstrap method to improve the reliability of small samples and the credibility of the S-N curve.

Based on the bootstrap method and the reliability of the original samples, two error ellipse models are proposed. The error ellipse model reasonably predicts that the discrete law of expanded virtual samples obeys two-dimensional normal distribution.

By comparing parameters obtained by the bootstrap method, improved bootstrap method (normal distribution) and error ellipse methods, it is found that the error ellipse method achieves the expansion of sampling range and shortens the confidence interval, which improves the accuracy of the estimation of parameters with small samples. Through case analysis, it is proved that the tangent error ellipse method is feasible, and the series of S-N curves is reasonable by the tangent error ellipse method.

The error ellipse methods can lay a technical foundation for life prediction of products and have a progressive significance for the quality evaluation of products.

In this paper, the authors examine how religious and political factors affect a firm's corporate governance diversity policies.

The authors develop five basic empirical models. Model 1 examines how religious beliefs and political affiliation determine whether a firm will establish diversity incentive in its senior executives' performance assessment. Model 2 investigates how the diversity goal, religious beliefs and political affiliation separately affect the level of actual diversity achieved. Model 3 examines how the diversity goal and environmental factors interact to affect the level of actual diversity achieved. Model 4 and Model 5 examine whether the diversity incentive in senior executives' compensation plan and the environmental factors (religious belief and political affiliation) help to reduce the compensation differentials between male and female executives.

The authors find that firms located in more liberal counties with more Mainline Protestants and less Republican voters in the United States are more likely to include workforce diversity as a criterion in evaluating their senior executives. The authors also provide evidence that firms with diversity goals have more female directors, more female senior executives and more minority directors. However, they find no evidence that the compensation differentials between male and female executives are smaller in these firms. Finally, they find that external environment affects the effectiveness of the implementation of the diversity goals.

In line withthis branch of research, the authors expand the literate on the link between corporate culture and corporate decision-making by investigating the non-financial performance measures. Besides the corporate decision-making in investment, financial reporting and social responsibilities as documented in prior studies, the authors argue that the religious beliefs and political affiliations could also affect the development and implementation of corporate non-financial performance goals in executive incentive contracts.