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The purpose of this paper is to prepare composite micro-arc oxide coatings with better wear resistance and corrosion resistance.

A nickel powder composite micro-arc oxide film was prepared on the surface of the magnesium alloy by the method of organically combining ultra-fine Ni powder with micro arc oxidation film layer. In this experiment, the changes in the corrosion resistance and microstructure of the composite film layer after adding Ni powder were studied, and the effect of the addition of glycerin on the corrosion resistance of the film layer was analyzed.

The results show that the ultra-fine nickel powder was successfully prepared by the liquid phase reduction method, and the micro-arc oxidation process was modified under the optimal addition amount. The surface of the micro-arc oxide film made of ultra-fine nickel powder was found by SEM to have smooth surfaces and few holes. According to X-ray diffraction analysis, the phase composition of the micro-arc oxide film layer was Mg, Ni, NiSiO₄, MgNi (SiO₄) and Mg₂SiO₄. According to the results of electrochemical tests, the corrosion resistance of the micro-arc oxidation composite film layer was improved after the addition of ultra-fine Ni powder, the corrosion current was greatly reduced and the impedance has been improved. And after adding glycerin, the surface of the film layer becomes denser, and the corrosion resistance of the micro-arc oxide film is significantly improved.

Through this experimental research, a micro-arc oxide coating of powder composite magnesium alloy was successfully prepared. The corrosion resistance of the micro-arc oxidation film layer has been improved, and certain functions had been given to the micro-arc oxidation composite film, which has increased the application field of magnesium alloys.

This paper aims to describe cooperation between public and private market players from different legal and religious orders. The author argues that such public–private partnerships (PPPs) enable the development of a possible convergence between selected areas of mainstream public finance and the Islamic moral economy (IME).

This paper explores the theory of both mainstream finance and the IME, and using deductive reasoning from axioms, develops the assumptions of a theoretical approach to heterodox PPP. The proposed method affects the ability to find common platforms between mainstream public finance and the IME, through the example of public–private investment projects.

This endeavour is subject to trade-offs between profit maximisation and social justice values on the basis of long-term PPP contracts. The author shows the assumptions under which this compromise would be beneficial to public entities, multicultural societies and conventional and Islamic investors. It is proposed to distribute profit to the owners up to a predetermined value, above which the PPPs would finance public services for persons otherwise excluded from them.

The success of this approach must depend on a compromise between profit maximisation as the sole investment objective and investment guided by social justice values. Private investors can achieve a capped level of profit on a long-term contract basis, and public partners can obtain long-term contracts for providing public goods. Both would undertake a project with a strong emphasis on corporate social responsibility, with particularly large opportunities in developing Islamic countries.

Presents over sixty abstracts summarising the 1999 Employment Research Unit annual conference held at the University of Cardiff. Explores the multiple impacts of globalization on work and employment in contemporary organizations. Covers the human resource management implications of organizational responses to globalization. Examines the theoretical, methodological, empirical and comparative issues pertaining to competitiveness and the management of human resources, the impact of organisational strategies and international production on the workplace, the organization of labour markets, human resource development, cultural change in organisations, trade union responses, and trans‐national corporations. Cites many case studies showing how globalization has brought a lot of opportunities together with much change both to the employee and the employer. Considers the threats to existing cultures, structures and systems.

Because of the small size and high integration of capacitive micromachined ultrasonic transducer (CMUT) component, it can be made into large-scale array, but this lead to high hardware complexity, so the purpose of this paper is to use less elements to achieve better imaging results. In this research, an optimized sparse array is studied, which can suppress the side lobe and reduce the imaging artifacts compared with the equispaced sparse array with the same number of elements.

Genetic algorithm is used to sparse the CMUT linear array, and Kaiser window apodization is added to reduce imaging artifacts, the beam pattern and peak-to-side lobe ratio are calculated, point targets imaging comparisons are performed. Furthermore, a 256-elements CMUT linear array is used to carry out the imaging experiment of embedded mass and forearm blood vessel, and the imaging results are compared quantitatively.

Through the imaging comparison of embedded mass and forearm blood vessel, the feasibility of optimized sparse array of CMUT is verified, and the purpose of reducing the hardware complexity is achieved.

This research provides a basis for the large-scale CMUT array to reduce the hardware complexity and the amount of calculation. At present, the CMUT array has been used in medical ultrasound imaging and has huge market potential.

This chapter describes how conversational computer agents have been used in collaborative problem-solving environments. These agent-based systems are designed to (a) assess the students’ knowledge, skills, actions, and various other psychological states on the basis of the students’ actions and the conversational interactions, (b) generate discourse moves that are sensitive to the psychological states and the problem states, and (c) advance a solution to the problem. We describe how this was accomplished in the Programme for International Student Assessment (PISA) for Collaborative Problem Solving (CPS) in 2015. In the PISA CPS 2015 assessment, a single human test taker (15-year-old student) interacts with one, two, or three agents that stage a series of assessment episodes. This chapter proposes that this PISA framework could be extended to accommodate more open-ended natural language interaction for those languages that have developed technologies for automated computational linguistics and discourse. Two examples support this suggestion, with associated relevant empirical support. First, there is AutoTutor, an agent that collaboratively helps the student answer difficult questions and solve problems. Second, there is CPS in the context of a multi-party simulation called Land Science in which the system tracks progress and knowledge states of small groups of 3–4 students. Human mentors or computer agents prompt them to perform actions and exchange open-ended chat in a collaborative learning and problem-solving environment.

This study examines the effect of political networking capability (PNC) and strategic capability on exploratory innovation/exploitative innovation through the mediation of absorptive capability (AC).

Using empirical survey data collected from 153 traditional manufacturing firms (TMFs) in China, the authors apply partial least squares structural equation modeling (PLS-SEM) combined with mediation analyses to test hypotheses.

PNC has a higher impact on exploratory innovation than exploitative innovation through AC. The authors thus provide novel empirical insights into independent variables of firms' ambidextrous innovation and their implementation mechanisms.

The authors highlight a unique situation of China and contribute to the literature on PNC and AC. The findings demonstrate that AC plays an important role in configuring government-obtained external resources into new products, thus influencing ambidextrous innovation strategic decisions.

TMFs' executives should enhance PNC to obtain more resources to conduct exploratory and exploitative innovation. Government officials and policymakers should strengthen the supervision of TMFs' innovation activities and adopt effective measures to ensure that TMFs could conduct more exploratory innovation as governments expected.

This study provides new insights by bridging research gaps in the literature and advances the insights of how TMFs' PNC/strategic capability directly and indirectly fosters exploratory and exploitative innovation via the mediating role of AC in China.

The number of farms engaged in grain production in China has been declining in recent years. Limited efforts have been devoted to examine why producers quit from grain production and how such exits affect China's grain output. Such information, however, is invaluable in understanding whether the exit from grain production should be encouraged and if so, how. The purpose of this paper is to identify the factors that influence farmers' decision to quit from grain production, with a view to drawing implications for devising policies to deal with such exits.

Both descriptive statistics and econometric techniques are used to analyse a set of unique and comprehensive farm‐level survey data to identify key factors that affect farmers' decision to quit from grain production.

Key factors that influence a farm to quit from, or stay in, grain production include: family size, the share of farming labour out of total family labour, per capita arable land, the proportion of land used for grain production, the share of family income from grains. It was also found that the level of grain prices and the sunk cost in farming, chiefly in grain production, also affect the likelihood that a household will stay or exit from grain production. Further, farmers in more economically developed regions are more likely to quit from grain production.

The paper's findings clearly indicate that farms with a larger scale of grain production and earning higher income from grain are the major contributors to China's grain production. Potential exists for China to raise its total grain output if the land from those exiting farmers is readily made available to larger producers, enabling them to further benefit from the economies of scale.

For Chinese companies that cross-list in Chinese A share and Hong Kong (H share) markets, the H share price has been consistently lower than the A share price by an average of 85% in recent years. This is puzzling because most institutional differences between the two markets have been eliminated since 2007. The purpose of this study is to explain the puzzle of the price difference of A+H companies.

Using all A and H share Chinese firms in the period 2007–2013 and a simultaneous equations approach, this study identifies three new explanations for the recent price difference.

First, utilizing a unique earning quality measure that is directly related to non-persistent components of fair value accounting under International Financial Reporting Standards (IFRS), this study finds that the lower the earnings quality, the lower the H share price relative to the A share price, and hence the greater the price difference. Second, the higher the myopic investor ownership in A share firms, the larger the A share price relative to the H share price. Third, the short-selling mechanism introduced to the A share market since 2010 helps reduce the price difference.

First, this study identifies three new explanations for the puzzle of the AH price difference which remains substantial even after the institutional and accounting standards differences between the two markets were eliminated. Second, we examine the impact of the implementation of fair value accounting under IFRS in an emerging market on the pricing difference of cross-listed shares and reveal that it can induce an unintended negative consequence on the pricing difference of cross-listed shares. Third, this study contributes to the literature on short sales by providing its mitigating role in pricing differences across two different markets. Finally, this study makes improvements in research design, which utilizes a unique measure of earnings quality that is directly related to the implementation of IFRS and a simultaneous equations approach that minimizes endogeneity concern.

The purpose of this paper was to develop a novel capacitive micromachined ultrasonic transducer (CMUT) reception and transmission linear array for underwater imaging at 400 kHz. Compared with traditional CMUTs, the developed transducer array offers higher electromechanical coupling coefficient and higher directivity performance.

The configuration of the newly developed CMUT reception and transmission array was determined by the authors’ previous research into new element structures with patterned top electrodes and into directivity simulation analysis. Using the Si-Silicon on insulator (Si-SOI) bonding technique and the principle of acoustic impedance matching, the CMUT array was fabricated and packaged. In addition, underwater imaging system design and testing based on the packaged CMUT 1 × 16 array were completed.

The simulation results showed that the optimized CMUT array configuration was selected. Furthermore, the designed configuration of the CMUT 1 × 16 linear array was good enough to guarantee high angular resolution. The underwater experiments were conducted to demonstrate that this CMUT array can be of great benefit in imaging applications.

Based on our research, the CMUT linear array has good directivity and good impedance matching with water and can be used for obstacle avoidance, distance measurement and imaging underwater.

This research provides a basis for CMUT directivity theory and array design. CMUT array presented in this paper has good directivity and has been applied in the underwater imaging, resulting in a huge market potential in underwater detection systems.

The purpose of this paper is to explore the optic performance of extended stilbene derivative.

Five steps were adopted to synthesise novel 4, 4′-bis (2-cyanostyryl) stilbene, which contained three vinyl units in the skeleton (S3E). The structure of S3E was characterised by ¹H NMR and EI-MS. Its absorption and emission spectra were also given.

Compared to C.I. Fluorescent Brightener 199, which contains two vinyl units in the skeleton, S3E showed obvious bathochromic shifts in both UV-VIS and FL spectra. The maximum absorption wavelength and fluorescent wavelength were at 390 nm and 464 nm, respectively, with Stoke’s shift of 74 nm. The absolute fluorescence quantum yield was 0.42. Thermogravimetric analysis (TGA) revealed that the weight loss of S3E was less than 5 per cent at 300 °C. Moreover, the light resistance test showed that S3E in PVC plate can keep the good fluorescent intensity for more than seven days exposed to xenon light. Therefore, it is believed that S3E could satisfy the requirements of colouring PVC as a fluorescent dye.

S3E can be used as a candidate of fluorescent dye in the development of thermoplastics.

The present paper designed and synthesised a new derivative of stilbene, which showed its preference to be a colourant of thermoplastics.