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The purpose of this paper is to investigate the temperature reliability for a parallel high-efficiency class-E power amplifier (PA).

To explore the relationship between temperature and direct current (DC) characteristics, output power, S parameters and efficiency of the PA quantitatively, a series of reliability experiments have been designed and conducted to study the temperature reliability for this PA.

From the results, the prominent performance degradation even failure is found during the testing. Furthermore, the thermal shock test can cause permanent failure, which is a great threat for PA.

Therefore, to ensure the good performance, the influence of temperature on PA reliability should be carefully considered during the stage of PA design.

All these can provide important guidance for the reliability design of PA.

All these can give some important guidance for PA application.

In addition, PA is usually designed according to the electrical properties at the room temperature. From the results above, it can be concluded that it may be unable to satisfy the performance requirement at high temperature. In turn, if it is designed according to the electrical properties at low temperature, the transistor often works in the super-saturated state, the reliability of PA will become the new problem. Therefore, to ensure the good performance, the influence of temperature on PA reliability should be carefully considered during the design.

The design and implementation of a broadband quasi-monolithic microwave integrated circuit (q-MMIC) power amplifier (PA) is presented for 0.2 to 2.2 GHz applications.

To obtain an efficient, high-gain and high-power performance with in a compact and low-cost size, the prototype is based on Gallium nitride (GaN) on SiC 0.25-µm transistors, whereas the passive matching networks are realized on an AlN substrate as thin film circuit.

Measured results of the q-MMIC PA across the 0.2 to 2.2 GHz band show at least 32 ± 3 dB small-signal gains, an output power of 7 to 12 W and an average power add efficiency greater than 54%. The q-MMIC occupies an area of 12.8 × 14.5 mm².

To the best of the authors’ knowledge, this work reports the first full integrated PA which covers the frequency range of 0.2 to 2.2 GHz and achieves the combination of highest gain, about 10 W output power, together with the smallest component size among all published GaN PAs to date.

The purpose of this paper is to examine the attitude control problem of a certain and big flexible satellite with unmodeled dynamics and unknown bounded disturbances and control input saturation; and to present a design method of robust adaptive controllers (RACs).

First, using the Lyapunov stability theory, it is shown that the proposed adaptive controller can guarantee the stability of the nonlinear system. Then, the parameters regulation method of the RAC is introduced. Finally, an RAC is designed for the object satellite model consisted of all the error‐source models.

The simulation results are compared with other results that are derived by using the typical PID controller. It is proved that the designed RAC has some properties of quickly response, high steady‐state precision and strong robustness.

The paper is of value in presenting a design method of RACs aiming at the object satellite with uncertainties and control input saturation.

The purpose of this paper is to review English-language publications about school principalship in China published between 1998 and 2013 and to present an overview of the authorship, topics, methodologies and key findings of these publications.

The methodology includes an exhaustive review of journal articles and book chapters about Chinese school principalship published in the English language. In total, 39 articles and 17 book chapters are identified for the 1998-2013 period. Qualitative analysis is conducted to determine the basic patterns of authorship, topics, methods and key findings. The changes or continuities in these patterns during the study period are also discerned.

The paper identifies several continuous and discontinuous patterns in each of the review categories and provides a better understanding of on-going research into the practice of school principalship in China. The results also suggest areas that require deeper exploration.

This paper explores the landscape of school principalship in China as reflected in the international literature and indicates the ways that this landscape has changed or remained the same over the years. As such, the paper contributes to the thin knowledge base concerning school principalship in China and sheds light on the enduring local-global tension in the evolution of education systems.

Forces of globalization have driven international convergence in corporate governance and accounting considerably over the past few decades. Nevertheless, despite the global trend, convergence of corporate governance and financial reporting remains a subject of debate. This research monograph critically examines whether China’s convergence with Anglo-American corporate governance principles and the International Financial Reporting Standards (IFRS) is likely to produce the expected outcomes of improving the transparency and comparability of accounting information in Chinese firms. In this chapter, we discuss the motivation for and the significance of the study; describe the issues associated with the adoption of internationally acceptable standards and principles in China; explain the theoretical framework used to inform the study and research methodology; and present the aim and objectives of the monograph.

The current paper aims to analyse the antecedents of leader–member exchange relationships (LMX) by specifically focusing on the influence of the supervisor’s feedback delivery tactic.

This study uses qualitative research methods with primary interviews as the main data source. Primary interviews with 40 managers from top supermarkets in Nigeria, South Africa and the UK were undertaken.

The authors found that both high-quality positive feedback and constructive criticisms produced the same feelings – more positive interpersonal relationships with their supervisors, higher levels of commitment to their organisations, higher job satisfaction and thus, high-quality LMX relationships. Where criticisms were delivered without greater interpersonal treatment, feedback was perceived as negative, and participants revealed lack of job satisfaction, lack of commitment to their organisations, poor interpersonal relationship with their supervisors, high turnover intent and thus low-quality LMX relationship.

To the best of the authors’ knowledge, the current paper is one of the first studies to highlight the consequences of different feedback delivery tactics on subsequent LMX quality particularly in African context. The authors specifically develop a process-based model of enhancing high-quality LMX, which shows the role of the supervisor’s feedback delivery tactic in the process. The authors also develop a process-based model that illustrates how negative/unconstructive feedback could result in a low-quality LMX. Finally, to the best of the authors’ knowledge, this paper is also one of the first to offer a comparative assessment between African and British (the UK) empirical settings and highlight some interesting dynamics concerning LMX quality and role of supervisor’s feedback delivery tactic.

The purpose of the paper is to investigate compensation and related welfare issues in the case of the expropriation of land for urban redevelopment in China.

A mixed methods quantitative and qualitative approach was selected to undertake the research. This involved a wide ranging qualitative review of the academic and policy literature to explore the relevant arguments and issues, combined with a quantitative regression analysis of survey data collected from research subjects.

The research identified the complex and changeable phenomena of urban village redevelopment in China, and the variable compensation arrangements used. The research found that monthly family income before land expropriation, monthly family expense before expropriation, the location of the housing expropriation and family unit size are important determinants for the property holders chosen methods of compensation. It also found that an increase in family size leads to a decreasing probability that the expropriated farmers choose the single monetary compensation relative to the alternative option of housing compensation. The degree of satisfaction with compensation, changes in monthly family income and expense are found to be significant determinants for changes in life satisfaction.

The research made the following four recommendations based upon the qualitative and quantitative analysis: that local governments should pay closer governance/ political attention to changes in the welfare of the farmers/ villagers whose property has been expropriated; that central and local government should aim to improve the compensation system for rural land and property expropriation, to make the compensation policy be perceived as fairer and more reasonable by citizens; that a broad National standard of compensation be used within a pragmatic locally focussed regime; that the Chinese Central, Provincial and Local governments can devise improved policy tools and make more effective policy interventions by learning from the experiences (both successes and failures) of other countries approaches to this topic. It also suggested that further research be undertaken investigating the multitude of local level policy experiments, as a way of developing better National compensation standards based upon those compensation standards that appear to be working – and have citizen support – at the local level.

The literature review identified recent developments in Chinese urban studies and originally synthesised both recent and longstanding work on the issue of urban villages in China. The research also suggested changes to the National and Local legal and policy framework for compensation cases in urban redevelopment expropriation scenarios.

Listening is often considered the cornerstone of the communication process, with feedback being a crucial skill for effective management. The primary objective of this article was to investigate the relationship between managers’ listening skills and feedback skills from their subordinates’ perspectives. Moreover, it explores the mediating effect of message-sending skills and the ability to deal with interference in this relationship.

This article deployed a quantitative, descriptive research design. The authors developed and distributed a self-administered questionnaire via non-probability convenience sampling, resulting in 304 useable responses.

The results of the main direct effect test (model 1) indicate that listening is positively associated with feedback. Model 2 established that message-sending skills did not directly mediate that relationship. On the other hand, the ability to deal with interference was found to mediate the relationship. Finally, model 4 showed the multi-mediating effect of message-sending skills and the ability to deal with interference in the relationship between listening and feedback.

As far as the researchers are aware, this paper is the first of its kind to show the ability to deal with interference as a mediating factor in a statistical model. Moreover, this study is the first to present a continuous intermediary role played by message-sending skills and the ability to deal with interference in the relationship between listening and feedback.

The purpose of this paper is to use comprehensive model to investigate the effects of particle physical properties on in-flight nano-particles behavior for the radio frequency suspension plasma spray.

In this paper, both the effects thermal properties of solvent and solid particle on the evolution of particle size, velocity and temperature are discussed. Besides, the numerical analysis is also conducted to investigate the influences of particle physical properties on the characteristic distributions of particles for poly-disperse cases.

Results show the thermal properties of solvent have critical effects on the discharged point of the solid particles, but little influence on the final particle velocity and size, as well as their distributions. The final state of particle temperature is mainly determined by the solid particle thermal properties, especially depending on the boiling point.

Most of the former studies took the experimental approaches and mainly focussed on the operating conditions effects. While beyond the operating conditions, the variety of particle physical and thermal properties also has strong effect on particle heating performance.

In order to further improve the accuracy of nonlinear simulation models, the purpose of this paper is to make some improvements to the general mode.

This paper adopts the calculation method of variable specific heat, taking the variation of gas‐oil ratios and discharge pressure into account, and establishes a nonlinear dynamic simulative model of biaxial gas turbine considering about the inertia of volume based on MATLAB/SIMULINK.

The simulation result, compared with test data, shows that this simulative model is more accurate to reflect the system's dynamic characteristics.

The hot inertial has not been taken into account. Meanwhile, the quantity of data is less, so this paper adopts interpolation method.

It is used to simulate calculation of gas turbines.

This paper adopts the calculation method of variable specific heat, considering the effect of the gas‐oil ratio variation and the discharge pressure variation (the total pressure of discharge duct) on the system.