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The purpose of this paper is to evaluate the effect of antioxidant 2,6-di-tert-butyl-p-methylphenol (BHT) on the thermal stability and fatigue resistance of spirooxazine and then study the properties of photochromic polyvinyl butyral resin (PVB) films.

BHT was introduced into the spirooxazine system by blending and covalent bonding. The properties of spirooxazine solutions and photochromic PVB films were studied.

The thermal stability and fatigue resistance of spirooxazine covalently linked (BHT-SO) or mixed (BHT/SO) with BHT were higher than the system without BHT, and BHT-SO was the better one. But acidic substance would greatly impair the fatigue resistance of spirooxazine. The optimum addition amount of BHT-SO2 to PVB was 2.5 per cent, and the minimum limit was 0.01 per cent. The fading kinetic and fatigue resistance of film were similar to the solution and better. Plasticizer could accelerate the fading rate and strengthen the mechanical properties of photochromic film but had no effect on the fatigue resistance.

Spirooxazine could be grafted onto the PVB chain to make the ring closure fading reaction slower.

In addition to the wide application prospects of photochromic materials in decoration, optical storage, etc., the photochromic PVB film in the car safety glass can absorb sunlight and turn blue, then fade to colorless when the sunlight disappears, making the interior environment more comfortable.

The introduction of BHT into the spirooxazine system not only exerts its ability to capture free radicals, but its bulky volume also increases the resistance of the ring closure, making the fading process slower.

In Beijing, urban agriculture (UA) experienced a corkscrew development with its role changing in decades: It has evolved from the purely production mode to multi-functional urban agriculture, fulfilling both social and ecological demands. At present, the practice of UA as well as the number of rural to urban migrants is growing rapidly in peri-urban Beijing. Through Multi-stakeholder Process for Action planning and Policy Design (MPAP) methodology and four in-depth case studies, we can see that UA activities are playing very important roles in reshaping peri-urban Beijing. Socially, UA induces the emergence of new migrant communities. While migrants rebuild their social network, they are changed by the city as well, which has also changed the local community. The new comers are on their way to creating a new balance. Physically, urban and peri-urban farmland limits urban sprawl, supplies agricultural products for everyday life, and reserves urban green spaces for recreation and leisure for citizens in Beijing, which has changed the landscape and land use and land cover (LUCC) pattern greatly. Under Beijing's land policy, the concentric configuration spatial allocation through multi-functional UA is formed, which at the same time due to migrants' UA activities are creating harmful and low efficient land use pattern which should be of concern.

The purpose of this paper is to examine the effects of internal corporate governance mechanisms on the capital structure decisions of Chinese-listed firms.

Using a large and more recent data set consisting of 2,386 Chinese-listed firms over the period from 1998 to 2012, the authors use different statistical methods (OLS, fixed effects and system GMM) to analyse the effects of firm-specific and corporate governance influences on capital structure.

The authors find that the proportion of independent directors and ownership concentration exert significant influence on the level of Chinese long-term debt ratios after controlling for firm-specific determinants and split share reforms. Further analysis separating the sample of this paper into state-owned enterprises (SOEs) and privately owned enterprises (POEs) suggests that ownership concentration in the hands of the state leads to decrease in debt ratios.

The finding implies that concentrated ownership in the hands of the state appears more efficient compared to their private counterparts in their monitoring role.

This paper extends prior literature, which has concentrated disproportionately on firm-specific influences on capital structure, to the effects of within-firm governance mechanisms on capital structure decisions. The paper contributes to the agency theory–capital structure discourse in an emerging country context where corporate governance system appears weak.

The stock indexes are an important issue for investors, and in this paper good trading strategies will be aimed to be adopted according to the accurate prediction of the stock indexes to chase high returns.

To avoid the problem of insufficient financial data for daily stock indexes prediction during modeling, a data augmentation method based on time scale transformation (DATT) was introduced. After that, a new deep learning model which combined DATT and NGRU (DATT-nested gated recurrent units (NGRU)) was proposed for stock indexes prediction. The proposed models and their competitive models were used to test the stock indexes prediction and simulated trading in five stock markets of China and the United States.

The experimental results demonstrated that both NGRU and DATT-NGRU outperformed the other recurrent neural network (RNN) models in the daily stock indexes prediction.

A novel RNN with NGRU and data augmentation is proposed. It uses the nested structure to increase the depth of the deep learning model.

This paper establishes a quality model for automation assembly of range hood impeller based on generalized grey relational degree, it improves the debugging efficiency of the newly developed assembly workstation.

First, spot check the trial production impellers and obtain three indexes that reflect the assembly quality of the impellers. Then, analyze the parameters that affect the assembly quality of the impeller using grey relational analysis (GRA), establish a model for the assembly quality of the range hood impeller based on the generalized grey relational degree and identify the main parameters. After that, analyze the transmission structure of automation assembly workstation, identify the reasons that affect parameters and propose improvement plans. Finally, a trial production is conducted on the automation assembly workstation after adopting the improved plan to verify the quality model of impeller automation assembly.

The research shows that compared to manual assembly, the automation assembly quality of the impeller using GRA model has been improved, shortening the debugging cycle of the newly developed assembly workstation.

The newly developed automation equipment will have some problems in the trial production stage, which often rely on the experience of engineers for debugging. In this paper, the automation assembly quality model of range hood impeller based on GRA is established, which can not only ensure the quality of finished impeller but also shorten the debugging cycle of the equipment. In addition, GRA can be widely used in the commissioning of other automation equipment.

This study has developed a set of impeller automation assembly workstation. The debugging method in the trial production stage is beneficial to shorten the trial production time and improve the economic benefits.

Studies of gang violence typically use police reports to investigate the structure of gang conflict, but overreliance on a singular data source could impede crime control efforts. Extending networked criminology, this study aims to explore what court records reveal about the directionality of gang conflicts.

Controlling for the presence of a civil gang injunction (CGI), the authors use multivariate quadratic assignment procedure regression models to disentangle factors thought to account for structural patterns of gang violence mapped from 933 prosecutions involving 307 gangs associated with violent conflict affecting the City of Los Angeles (1998–2013). Specifically, the authors compare competitive advantage to the explanatory power of turf proximity.

One measure of turf proximity outperforms all other explanatory factors – gangs with turf centrally positioned in a turf adjacency matrix are significantly more likely to launch attacks, be victimized and exhibit the highest levels of imbalance in their violent involvements. Regarding competitive advantage, the number of cliques and level of internal conflict are significant. Finally, being subject to a CGI is associated with initiating violence.

Court cases offer a feasible alternative to police data when investigating patterns of intergroup street gang violence.

Despite big data analytics capability (BDAC) has received extensive attention, how and under what conditions BDAC influences green supply chain integration (GSCI) remains unclear. This study draws on organizational information processing theory to examine the mediating effect of supply chain visibility in the BDAC–GSCI link and the moderating effects of flexibility- and control-oriented culture.

The authors examined the research model using two-waved survey data gathered from 317 Chinese firms. The authors employed hierarchical regression analysis and bootstrapping method to test hypotheses and assessed the robust of theoretical model using structural model.

The authors found that BDAC facilitates all three dimensions of GSCI. Supply visibility mediates the relationship between BDAC and all three dimensions of GSCI, whereas demand visibility only mediates the positive effects of BDAC on green internal and customer integration. In addition, control-oriented culture strengthens the positive impacts of BDAC on supply and demand visibility, while the moderating effects of flexibility-oriented culture are insignificant.

This research contributes to opening the “black box” of how BDAC affects GSCI and provides novel guidelines for firms enhancing the degree of GSCI.

The differential magnetic gradient tensor system is usually constructed from the three-axis magnetic sensor array. While the effects of measurement error, sensor performance and baseline distance on localization performance of such systems have been widely reported, the research about the effect of spatial design of sensor array is less presented. This paper aims to provide a spatial design method of sensor array and corresponding optimization strategy to localization based on magnetic tensor gradient to get the optimum design of the sensor array. Based on the results of simulation, magnetic localization systems constructed from the proposed array and the traditional array have been built to carry out a localization experiment. The results of experiment have verified the effectiveness of magnetic localization based on the proposed array.

The authors focus on the localization of the magnetic target based on magnetic gradient by using three-axis magnetic sensor array and combine a design method with corresponding optimization strategy to get the optimum design of the sensor array.

This paper provides an array design and optimization method for magnetic target localization based on magnetic gradient to improve the localization performance.

In this paper, the authors focus on the magnetic localization based on magnetic gradient by using three-axis magnetic sensors and study the effect of the spatial design of sensor array on localization performance.

With the analysis of the causes of corruption, this study aims to investigate specific anti-corruption measures that can be implemented to reform the political system and the social climate of China.

This study examines 97 severe corruption cases of high-ranking officials in China, which occurred between 2012 and 2015. As this insinuates that both institutional and social corruption are major problems in China, the analysis delves into multiple facts of corruption, including different types, four primary underlying causes, and suggestions regarding the implementation of three significant governmental shifts that focus on investigation, prevention tactics and legal regulations.

China’s corruption is not only individual-based but also it has developed into institutional corruption and social corruption. Besides human nature and instinct, the causes of corruption can be organised into four categories, namely, social customs, social transitions, institutional designs and institutional operations. For the removed high-ranking officials, the formation of interest chains was an important underlying cause behind their corruption.

This study makes a significant contribution to the literature because this study provides a well-rounded approach to a complex issue by highlighting the significance of democracy and the rule of law as ways to regulate human behaviour to combat future corruption.

Aluminum alloy is susceptible to chloride ion attack in sea water, resulting in pitting damage and hence serious security risks for the related applications. To improve the corrosion resistance of Al alloy, micro-arc oxidation (MAO) technology has been developed to produce a protective dense oxide layer on top of Al alloy. However, the mechanism of MAO-induced corrosion resistance is still not fully understood, particularly on local corrosion issue. This paper aims to focus on comprehensively studying the corrosion-resistance mechanism by a series of technologies.

The corrosion behavior of samples was studied by open circuit potential (OCP), potentiodynamic polarization (PDP), electrode impedance spectroscopy (EIS) and localized electrode impedance spectroscopy (LEIS) tests in NaCl solution.

The MAO-coated Al alloy shows a more positive corrosion potential and a higher corrosion current density compared to the untreated counterpart, indicating a significantly enhanced corrosion-resistance. The study of surface morphology and structure also suggest significantly enhanced corrosion-resistance due to the MAO treatment.

Based on the results, a new corrosion model was proposed to describe the influence of MAO treatment on the corrosion process and corrosion mechanism of Al alloy, providing insights on the design of the corrosion-resistance coating for metallic alloys in marine applications.