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1 – 10 of 163Liemei Yuan, Gang Cai and Jun Gao
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…
Abstract
Purpose
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.
Design/methodology/approach
BHT was introduced into the spirooxazine system by blending and covalent bonding. The properties of spirooxazine solutions and photochromic PVB films were studied.
Findings
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.
Research limitations/implications
Spirooxazine could be grafted onto the PVB chain to make the ring closure fading reaction slower.
Practical implications
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.
Originality/value
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.
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Xu Zhang, Mingling Zhai, Yanyan Wang, Yulei Gao, Haoliang Zhao, Xiang Zhou and Jun Gao
In order to verify the feasibility of different techniques, this chapter further studies the adaptability of two massive straw biomass applications in rural areas in China.
Abstract
Purpose
In order to verify the feasibility of different techniques, this chapter further studies the adaptability of two massive straw biomass applications in rural areas in China.
Methodology/approach
The methods of assessing biomass power generation project with Life Cycle Assessment (LCA), survey and field test of one biogas station, and game-theoretic analysis are adopted.
Findings
The following conclusions can be drawn: The air pollution costs account for more than 60% of the total environmental cost, followed by depreciation expense and maintenance fee of 18%, compared to that of biomass power generation at 0.01711 CNY/kWh. The adopted greenhouse sunlight technology of Solar Biogas Plant in Xuzhou, China, raises the inside average temperature by 11.0 °C higher than outside and keeps the pool temperature above 16 °C in winter, ensuring a gas productivity of biogas project in winter up to 0.5–0.7 m3/m3 by volume. This chapter also analyzes the information cost incurred by asymmetric information in biomass power generation via game theory method and illustrates the information structure with game results. It provides not only a foundation for the policy research in promoting straw power generation but also theoretical framework to solve the problem of straw collection.
Social implications
These studies will propose solutions to relevant problems arisen in the running process.
Originality/value
These studies are all based on real cases, field research, and appropriate theoretical analyses, so, they can reduce the relevant costs and promote the application of relevant technologies.
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Zhang Feifei, Cai Jianming and Liu Gang
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…
Abstract
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.
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Denise Bedford and Thomas W. Sanchez
This chapter focuses on community and social group networks. All six facets of knowledge networks are described. The importance of three of the six facets is called out, including…
Abstract
Chapter Summary
This chapter focuses on community and social group networks. All six facets of knowledge networks are described. The importance of three of the six facets is called out, including geography, domain, and the messages exchanged across the network. The authors provide profiles of five networks, including family networks, neighborhood networks, issue and support networks, community organization networks, gangs and criminal networks, and sports and gaming networks.
Agyenim Boateng, Huifen Cai, Daniel Borgia, Xiao Gang Bi and Franklin Nnaemeka Ngwu
The purpose of this paper is to examine the effects of internal corporate governance mechanisms on the capital structure decisions of Chinese-listed firms.
Abstract
Purpose
The purpose of this paper is to examine the effects of internal corporate governance mechanisms on the capital structure decisions of Chinese-listed firms.
Design/methodology/approach
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.
Findings
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.
Research limitations/implications
The finding implies that concentrated ownership in the hands of the state appears more efficient compared to their private counterparts in their monitoring role.
Originality/value
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.
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Yuefeng Cen, Minglu Wang, Gang Cen, Yongping Cai, Cheng Zhao and Zhigang Cheng
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
The experimental results demonstrated that both NGRU and DATT-NGRU outperformed the other recurrent neural network (RNN) models in the daily stock indexes prediction.
Originality/value
A novel RNN with NGRU and data augmentation is proposed. It uses the nested structure to increase the depth of the deep learning model.
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Keywords
M.A. Xianglin, Haochen Cai, Qiming Yang, Gang Wang and Kun Mao
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Practical implications
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.
Originality/value
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.
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Gisela Bichler, Alexis Norris and Citlalik Ibarra
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Originality/value
Court cases offer a feasible alternative to police data when investigating patterns of intergroup street gang violence.
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Haiqing Shi, Taiwen Feng and Zhanguo Zhu
Despite big data analytics capability (BDAC) has received extensive attention, how and under what conditions BDAC influences green supply chain integration (GSCI) remains unclear…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Originality/value
This research contributes to opening the “black box” of how BDAC affects GSCI and provides novel guidelines for firms enhancing the degree of GSCI.
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Shengzhi Chen, Minghua Zhu, Qing Zhang, Xuesong Cai and Bo Xiao
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
This paper provides an array design and optimization method for magnetic target localization based on magnetic gradient to improve the localization performance.
Originality/value
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.
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