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This paper aims to characterize the surface film formed on Alloys 800 and 690 in chloride and thiosulfate-containing solution at 300°C.

Alloy 800 and 690 were immersed in chloride and thiosulfate-containing solution at 300°C up to five days, and then the surface film was analyzed by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and energy dispersive X-ray spectrometers (EDX).

Through static immersion experiments in a high-temperature and high-pressure water environment, the alloy samples covered by surface film after five days of immersion were obtained. The morphology of the surface film was characterized at both horizontal and cross-sectional scales using SEM and focused ion beam-TEM techniques. It was observed that due to the influence of the quartz lining, the surface film primarily exhibited a bilayered structure. The first layer contained a significant amount of SiO₂, with a higher content of metal hydroxides compared to metal oxides. The second layer was predominantly composed of Fe, Ni and Cr, with a higher content of metal oxides compared to metal hydroxides.

The results showed that the materials of the lining of the autoclave could significantly influence the film composition of the tested material, which should be paid attention when analyzing the corrosion mechanism at high temperature.

Bike sharing becomes suddenly hot up in China since the end of 2016. However, few studies have focused on shared bicycle users’ behavior. To fill this research gap, this paper aims to develop an integrated model to investigate factors that affect shared bicycle users’ subjective well-being.

A field survey with 220 shared bicycle users is conducted to test the research model and hypotheses.

The highlights are that perceived value has positive effect on users’ life satisfaction. Specially, it is interesting to find that hedonic value has the greatest impact on users’ life satisfaction, followed by social value and utilitarian value. Perceived risks which including privacy risks, financial risks and functional risks act as a moderating role between perceived value and users’ life satisfaction.

First, the authors clear factors that affect users’ subjective well-being from the perspective of perceived value. The results deepen our understanding about the effect of perceived value on users’ subjective well-being. Second, the current researches have ignored the effect of perceived risks on users’ subjective well-being. The authors filled that gap and found that perceived risks which including privacy risks, financial risks and functional risks act as a moderating role between perceived value and users’ subjective well-being.

This paper aims to prepare a composite film on LY12 aluminum (Al) alloy by immersing in dodecyl phosphate and cerium nitrate solution by self-assembling methods. The effect of dipping sequence in dodecyl phosphate and cerium nitrate solution on the corrosion resistance of the composite film is studied.

The corrosion resistance of the dodecyl phosphate/cerium composite film is investigated by electrochemical measurement and film composition analysis.

The dipping sequence in dodecyl phosphate and cerium nitrate solutions has a significant impact on the corrosion resistance of the composite film. It shows best corrosion resistance by first dipping in dodecyl phosphate and then dipping in cerium nitrate solution.

The research shown in this work lays a scientific basis of the film preparation for industrial applications in the future.

Hydroelectric power is widely used because it is environmental friendly, renewable and green. The cavitation is an inevitable phenomenon during the operation of hydro turbine, which is related to the efficiency and service life of the unit. This paper aims to discriminate the phenomenon of the incipient cavitation, prevent the early destruction and avoid the irreversible damage to hydro turbine.

The paper tries to find out the characteristics of cavitation entirely through a variety of features. The method comprises collection of the signals using a hydrophone, acceleration sensor and acoustic emission sensor; analyzing cavitation signal by using the way of wavelet time-frequency, peak factor and power spectral density; and comparing the different wavelet basis for analyzing signals and find the most suitable one.

The analyzed results show that the wavelet basis of morlet is more suitable for the cavitation signals. The hydrophone can distinguish the different operating conditions and discriminate the difference between the phenomenon of incipient cavitation and the other state of cavitation. The results show that when the hydrophone and acceleration sensors are used, the accuracy rate goes up to 75 per cent, which meets the requirements for the detection for incipient cavitation.

This paper focuses on finding the best sensor to discriminate the operating state of incipient cavitation to prevent early destruction.

Cyber physical system (CPS) has attracted much attention from industry, government and academia due to its dramatic impact on society, economy and people’s daily lives. Scholars have conducted a number of studies on CPS. However, despite of the dynamic nature of this research area, a systematic and extensive review of recent research on CPS is unavailable. Accordingly, this paper conducts an intensive literature review on CPS and presents an overview of existing research on CPS. The purpose of this paper is to identify the challenges of studying CPS as well as the directions for future studies on CPS.

This paper examines existing literatures about CPS from 2006 to 2018 in Compendex, presenting its definition, architectures, characteristics and applications.

This study finds that CPS is closely integrated, diversified and large-scale network with complex multiple time scales. It requires dynamic reorganization/reconfiguration, mass computing, and closed, automated and control circuits. Currently, CPS has been applied in smart manufacturing, medical systems, smart city and smart libraries. The main challenges in designing CPS are to develop, to modify, to integrate abstractions and to set predictable timing of openness and physical interconnection of physical devices. Furthermore, security is a key issue in CPS.

This study adds knowledge to the existing literature of CPS by answering what the current level of development on CPS is and what the potential future research directions of CPS are.

To implement a risk-based regulatory approach, this paper aims to make an assessment on customers' money laundering risk and conducts some applications.

During the transition of a regulatory approach from “rule-based” to “risk-based”, this paper considers that the area of a customer, types of business and the industries to which the customer belongs are the main indicators to judge money laundering risk of a customer. Based on the statistical analysis of 221 typical money laundering cases, first-class index weights are given by using the entropy weight method and then by combining with the membership function, this paper determines a customer’s money laundering risk levels. On the basis of the entropy weight method, this paper uses the C5.0 algorithm to construct a decision tree model and then carries out application research on customer money laundering risk assessment to verify the effectiveness of the entropy weight method and the decision tree model.

This empirical research found the weights of three key money laundering indicators: customer areas, business types and corresponding industries.

Asserting that current money laundering risk assessments of customers are marginal at best, this paper contends from the perspective of practice, and applies the entropy weight method and the decision tree model for money laundering risk assessment of customers.

This study aims to solve the problem of job scheduling and multi automated guided vehicle (AGV) cooperation in intelligent manufacturing workshops.

In this study, an algorithm for job scheduling and cooperative work of multiple AGVs is designed. In the first part, with the goal of minimizing the total processing time and the total power consumption, the niche multi-objective evolutionary algorithm is used to determine the processing task arrangement on different machines. In the second part, AGV is called to transport workpieces, and an improved ant colony algorithm is used to generate the initial path of AGV. In the third part, to avoid path conflicts between running AGVs, the authors propose a simple priority-based waiting strategy to avoid collisions.

The experiment shows that the solution can effectively deal with job scheduling and multiple AGV operation problems in the workshop.

In this paper, a collaborative work algorithm is proposed, which combines the job scheduling and AGV running problem to make the research results adapt to the real job environment in the workshop.

The purpose of this paper is to extend current knowledge by focusing on three geographic factors (minority-Han residential segregation, rural-urban disparities and regional differences) and their effects on educational and occupational outcomes of Chinese ethnic minorities from 2000 to 2010.

Data from the 2000 and 2010 Chinese decennial censuses were used, and both descriptive and multivariate analyses were conducted.

Results revel that there were regional differences in terms of educational segregation between minorities and the Han. It was also difficult for minority groups that were residentially segregated from the Han and mainly located in rural areas or western/southeastern regions to obtain high-level education. When minority groups were residentially segregated from the Han, they tended to have higher levels of occupational segregation from the Han; while minority groups with larger percentages of rural residents tended to have smaller percentages of people obtained high-status occupations. Despite China’s rapid social and economic development, ethnic disparities in education did not significantly change, and ethnic gaps in occupational attainment were widened from 2000 to 2010.

Geographic sources of ethnic conflicts in China should not be overlooked, and future researchers should also conduct studies on Chinese ethnic minorities at individual or household level.

This study contributes to the literature in two major ways: first, all Chinese minority groups were included in the analyses to clarify intra-ethnic differences; second, data from two Chinese decennial censuses and longitudinal statistical modeling were used to investigate the effect of time on ethnic stratification.

This paper aims to explore the development and implementation of enterprise policy in China, and the emergence of intermediaries and local strategies designed to encourage SME development.

The paper is based on interviews and workshops held with local and national government in 2003 and 2006, and informed by reference to and analysis of the policy and academic literature.

The dynamics and nature of local implementation of national enterprise legislation are mapped out, indicating an interactive dynamic between central government directive, local government adoption and response, and localised dynamics of enterprise and economic development. This “three‐way” model provides a nuanced explanation of local implementation of national enterprise legislation.

The framework can be used at the municipal level to understand how national enterprise legislation can be implemented. The framework also points to wider patterns of local implementation of national government legislation.

The paper provides a detailed model of local policy implementation, using the SME Promotion Law as a specific case of legislation.