Xinyue Liang, Hui Qiao, Guilong Xu, Yanchong Zhang, Yun Liang and Jian Hu
The flammability of poly-acrylate (PA) resin is a major disadvantage in applications that require flame resistance. Many studies, including the authors’ previous study, have…
Abstract
Purpose
The flammability of poly-acrylate (PA) resin is a major disadvantage in applications that require flame resistance. Many studies, including the authors’ previous study, have proved that covalent-incorporated phosphorous-containing (P-containing) monomer onto the PA resin can exhibit better flame resistance than that by an additive approach. However, other properties such as thermal stability, coating properties are still deteriorated. To further improve the flame-retardancy and other comprehensive properties of the P-containing PA resin, in this study, melamine formaldehyde(MF) resin was used not only as a curing agent to enhance the coating properties of the PA resin, but also as a nitrogen-containing (N-containing) resin to form a P-N synergistic effect and therefore further improve its flame retardancy.
Design/methodology/approach
Epoxy resin phosphorous acid-modified (EPPA-modified) PA (EPPA-PA) resin was first prepared and then using MF resin as curing agent. The flame retardancy of the cured resin was tested by the limiting oxygen index (LOI) and UL 94 methods. The thermal stability of the cured resin was studied by TGA. The coating technology such as adhesion property, pencil hardness and anti-solvent properties were characterized according to methods of International Standards ISO2409-1992, ISO 15184-1998 and ISO-15184-2012, respectively. The micro-char morphology of the char residue was observed by SEM.
Findings
The results showed that by using MF resin as curing agent has provided the PA resin with excellent coating properties and thermal stability, but also gave a P-N synergistic effect which has greatly enhanced the flame retardancy of the cured resin. The cured resin system containing only 1.7 Wt.% P content and 5.3 Wt.% N content can reach a LOI of 26.9 per cent and pass the V-0 rating in the UL-94 test.
Research limitations/implications
This resin system releases formaldehyde due to the MF resin.
Practical implications
It is expected that the large-scale production of this EPPA-PA resin cured by MF resin system will enable practical industrial applications.
Originality/value
This method for the synthesis of a P- and N-containing PA resin system is newfangled.
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Abstract
Purpose
The flammability of poly-acrylate (PA) resin is a major disadvantage in applications that require flame resistance. It has been reported that a flame-retardant PA resin could be prepared by covalent incorporate phosphorous containing monomer with vinyl group via free radical polymerization, and the prepared modified PA resin is expected to exhibit better flame resistance than those by an additive approach. However, the phosphorus-containing monomers reported previously are made from expensive or toxic materials, and the production procedure is tedious and under harsh reaction conditions, which are not feasible for industrial application. Therefore, the purpose of this paper is the preparation of flame-retardant PA resin modified by epoxy resin phosphorous acid (EPPA) and the study of its flame retardancy.
Design/methodology/approach
EPPA is first prepared by epoxy resin E-51 and phosphorous acid and then used to prepare phosphorous containing PA resin by free radical polymerization. The flame retardancy of the prepared EPPA-modified PA (EPPA-PA) resin is studied.
Findings
The results show that EPPA can graft onto the PA polymer chain by free radical polymerization, the flame retardancy of the EPPA-PA resin increases as the EPPA content increasing. The flame retardancy of EPPA-PA resin prepared reaches 27.8% and can pass the V-0 rating in the UL-94 test when EPPA content is 30.0%. SEM and EDS results indicate that phosphorous element in the EPPA-PA resin shows a condensed-phase flame retardant effect.
Research limitations/implications
The grafting degree of EPPA cannot be accurately tested.
Practical implications
It is expected that the large-scale production of this epoxy resin phosphoric acid modified PA resin will enable practical industrial applications.
Originality/value
This method for synthesis of epoxy resin phosphoric acid modified PA resin is newfrangled.
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Yong-Hai Li, Zhi-Ping Fan and Guang-Hui Qiao
The purpose of this paper is to present a novel framework for recommending desirable products to active customers with the consideration of not only their preferences but also the…
Abstract
Purpose
The purpose of this paper is to present a novel framework for recommending desirable products to active customers with the consideration of not only their preferences but also the products’ quality performances and their e-retailers’ service performances under e-commerce.
Design/methodology/approach
A framework in support of the product recommendation is presented. Three modules are involved in the framework, i.e. data collection and preference analysis module, hybrid recommendation module and recommendation generation module. First, preferences of different types of customers are inferred through analysis of their behavioral data and then a paradigm is adopted based on cased-based reasoning to generate candidate recommendation products. Further, recommendation lists for different types of customers are obtained through measurement of the quality and service performances concerning each candidate recommendation product.
Findings
To illustrate the performance of the presented framework, a simulation study comparing the approach developed based on the framework and the traditional approach is conducted. The experiment results show that the developed approach outperformed the traditional approach in term of average rank score. This means that incorporating the consideration of product performance and customer service factors can play an important role in product recommendations.
Originality/value
The presented framework can overcome the defect that low conversion rate of recommended products to actually purchased ones suffered by the traditional approach. In addition, the use of the presented framework can not only help customers to obtain desirable products and save searching time but also supervise and urge e-retailers to pay more attention to the quality and service performances.
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Jiannan Wu, Yuqian Yang and Liang Ma
This chapter looks into China's experiences with embracing new steering instruments to promote social stability, with particular reference to the protection of households involved…
Abstract
This chapter looks into China's experiences with embracing new steering instruments to promote social stability, with particular reference to the protection of households involved in city regeneration projects. During the closing years of the twentieth century, China experienced a fundamental transition, from a planned mode of urban regeneration to a new pattern that emphasised the involvement of the market. Under the planned regime, households affected by regeneration projects were provided with new apartments and temporary housing, all financed by the local government. Economic incentives were rarely employed to encourage households to resettle, as resettlement was seen as a civil obligation. The new approach, featuring marketisation, however, requires the affected households to pay for their new houses using monetary compensation and subsidies from the local governments. The local governments are strongly motivated to save such costs and thus provide limited compensation, and consequently complaints from the affected households have continued to grow (Peerenboom & He, 2009).
Hui Chen, Qiao-zhuan Liang and Yue Zhang
The current research studies are inconclusive about the positive or negative effects of group faultlines, especially in the Chinese context. To address this issue, this study aims…
Abstract
Purpose
The current research studies are inconclusive about the positive or negative effects of group faultlines, especially in the Chinese context. To address this issue, this study aims to adopt an interactive perspective to explore the group interaction process. Specifically, this study proposes a new construct “interactive faultlines” to integrate overall faultlines and separate faultlines, and based on categorization-elaboration model (CEM), develops an integrated moderated mediation model to examine when and how interactive faultlines facilitate or inhibit group creativity.
Design/methodology/approach
This study tests the model with the samples of 405 employees from 95 groups in China, carrying out confirmatory factor analysis, regression analysis and process.
Findings
This study finds that the indirect effect of informational faultlines on group creativity through information elaboration is positive when social faultlines are low, but negative when social faultlines are high.
Practical implications
This research provides some practical implications on how to manage group compositions and coordinate group interaction process to make full use of the potential benefits of diverse information and avoid the possible detriment from social categorization.
Originality/value
This study adopts an interactive perspective to consider informational faultlines and social faultlines simultaneously, and constructs a focal concept “interactive faultlines.” Based on CEM, it also offers a fine-grained picture of the double-edged relationship between informational faultlines and group creativity by identifying social faultlines as a moderator and information elaboration as a mediator, which advances knowledge about the linkages between interactive faultlines and group creativity. Particularly, this study is rooted in the Chinese context and brings in indigenous attributes derived from an analysis of Eastern cultures to elucidate the particular effect of informal social connections.
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Xueyan Zhang, Xiaohu Zhou, Qiao Wang, Hui Zhang and Wei Ju
Based on social influence theory (SIT) and social capital theory, this paper aims to explore the mediating role of entrepreneurial networks between technological entrepreneurs'…
Abstract
Purpose
Based on social influence theory (SIT) and social capital theory, this paper aims to explore the mediating role of entrepreneurial networks between technological entrepreneurs' political skills and entrepreneurial performance and whether market dynamics positively moderates this relationship.
Design/methodology/approach
This study collected data from 454 technological entrepreneurs in Beijing, Shanghai, Hangzhou, Guangzhou, Zhengzhou in China and examined four hypotheses by hierarchical regression analysis and bootstrapping analysis in an empirical design.
Findings
Results reveal that technological entrepreneurs' political skills not only have a direct positive impact on entrepreneurial performance (β = 0.544, t = 12.632, p < 0.001), but also have an indirect positive impact on entrepreneurial performance through entrepreneurial networks (β = 0.473, t = 10.636, p < 0.001). Entrepreneurial networks play a mediating role between entrepreneurs' political skills and entrepreneurial performance with 95% bias-corrected confidence intervals [0.034, 0.015]. Market dynamics plays a moderating role in the relationship among technological entrepreneurs' political skills, entrepreneurial networks and entrepreneurial performance (entrepreneurial performance: β = 0.190, t = 4.275, p < 0.001; entrepreneurial networks: β = 0.135, t = 4.455, p < 0.001). When market dynamics is high, technological entrepreneurs' political skills have a significant positive effect on entrepreneurial networks (simple slope = 0.309, t = 7.656, p < 0.001); but when market dynamics is low, there is no significant correlation between political skills and entrepreneurial networks (simple slope = 0.039, t = 0.966, p > 0.05).
Research limitations/implications
The study relies on self-reported data from single informants. Although the severity of common method bias is tested through two methods, future research designs should avoid the influence of common method bias. Future research should adopt a vertical tracking design, collect data from multiple sources and use subjective assessment and objective indicators to measure variables. In addition, the applicability of the results outside China is worth further empirical exploration. Therefore, the authors hope that future studies can replicate the research to different countries, different cultural backgrounds and different organizational sections to explore the generalizability of the results.
Practical implications
The findings provide useful suggestions for entrepreneurs, who can use political skills to build a strong entrepreneurial network to improve their entrepreneurial performance. The results also suggest that entrepreneurs should pay more attention to cultivating and developing their political skills through methods such as training and practice. In addition, the conclusion is of great implications to enrich the content of entrepreneurship education and guide entrepreneurship practice.
Originality/value
These findings enrich SIT and social capital theory by providing the empirical evidence of the effect of entrepreneurs' political skills on entrepreneurial performance through entrepreneurial network. They also provide deeper insights into market dynamics research by uncovering the moderating role of market dynamics in the relationship between entrepreneurs' political skills, entrepreneurial networks and entrepreneurial performance.
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This paper aims to give a brief review on behavioral economics and behavioral finance and discusses some of the previous research on agents' utility functions, applicable risk…
Abstract
Purpose
This paper aims to give a brief review on behavioral economics and behavioral finance and discusses some of the previous research on agents' utility functions, applicable risk measures, diversification strategies and portfolio optimization.
Design/methodology/approach
The authors also cover related disciplines such as trading rules, contagion and various econometric aspects.
Findings
While scholars could first develop theoretical models in behavioral economics and behavioral finance, they subsequently may develop corresponding statistical and econometric models, this finally includes simulation studies to examine whether the estimators or statistics have good power and size. This all helps us to better understand financial and economic decision-making from a descriptive standpoint.
Originality/value
The research paper is original.
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Chuang Cheng, Hui Zhang, Hui Peng, Zhiqian Zhou, Bailiang Chen, Zhiwen Zeng and Huimin Lu
When the mobile manipulator is traveling on an unconstructed terrain, the external disturbance is generated. The load on the end of the mobile manipulator will be affected…
Abstract
Purpose
When the mobile manipulator is traveling on an unconstructed terrain, the external disturbance is generated. The load on the end of the mobile manipulator will be affected strictly by the disturbance. The purpose of this paper is to reject the disturbance and keep the end effector in a stable pose all the time, a control method is proposed for the onboard manipulator.
Design/methodology/approach
In this paper, the kinematics and dynamics models of the end pose stability control system for the tracked robot are built. Through the guidance of this model information, the control framework based on active disturbance rejection control (ADRC) is designed, which keeps the attitude of the end of the manipulator stable in the pitch, roll and yaw direction. Meanwhile, the control algorithm is operated with cloud computing because the research object, the rescue robot, aims to be lightweight and execute work with remote manipulation.
Findings
The challenging simulation experiments demonstrate that the methodology can achieve valid stability control performance in the challenging terrain road in terms of robustness and real-time.
Originality/value
This research facilitates the stable posture control of the end-effector of the mobile manipulator and maintains it in a suitable stable operating environment. The entire system can normally work even in dynamic disturbance scenarios and uncertain nonlinear modeling. Furthermore, an example is given to guide the parameter tuning of ADRC by using model information and estimate the unknown internal modeling uncertainty, which is difficult to be modeled or identified.
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Both Hong Kong and Singapore leverage teacher collaboration to improve student learning, but state reforms differ in how teacher collaborative capabilities are prioritized. This…
Abstract
Purpose
Both Hong Kong and Singapore leverage teacher collaboration to improve student learning, but state reforms differ in how teacher collaborative capabilities are prioritized. This paper provides a nuanced comparison of Hong Kong and Singapore teachers' values (risk-taking, power distance and uncertainty avoidance) to develop insights into how different policy focuses cultivate teachers' capabilities to focus on improving student learning.
Design/methodology/approach
Employing Hargreaves and Fullan's (2012) concept of professional capital, statistical analyses determine teachers' values profiles of high, medium and low professional capital in the respective contexts. Leveraging related research on Singapore teachers (Lee and Lee, 2018), nuances in teachers' values in the Hong Kong results are identified via cluster analysis and explained via structural equation modelling.
Findings
Medium professional capital Hong Kong teachers' values matched Singapore's, but teachers in other clusters are nuanced. Compared to Singapore teachers with similar levels of professional capital, high professional capital Hong Kong teachers have higher uncertainty avoidance, while low professional capital teachers are the opposite. In Hong Kong, high uncertainty avoidance values positively influence teacher leadership and focus on student learning. Nevertheless, as with their Singapore counterparts, high professional capital Hong Kong teachers have low power distance and high risk-taking values.
Originality/value
This paper raises awareness regarding policy's influence in cultivating teachers' values and their transformational change capabilities. By comparing two hierarchical Chinese societies, the discussion questions whether Chinese and Western cultural influences are mutually exclusive, and whether transformational change in cultural values, if achievable, is necessary.
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Rachel R. Weinberger and Lisa Jacobson
In Guangzhou, the largest city in southern China, car ownership is increasing beyond the capacity of the road system. This leaves streets gridlocked and parking facilities…
Abstract
Purpose
In Guangzhou, the largest city in southern China, car ownership is increasing beyond the capacity of the road system. This leaves streets gridlocked and parking facilities inaccessible, thus under-utilized. At the same time, Guangzhou's zoning code calls for additional off-site parking which is likely to encumber development. This chapter documents and discusses policies in Guangzhou that affect and are affected by parking and how they relate to City goals.
Methodology/approach
The chapter explores the relationship between three interrelated topics: (1) today’s parking policies in Guangzhou, regulated by a variety of municipal agencies, (2) case studies of two large developments and their respective parking supplies and demands, and (3) city goals and objectives.
Findings
There is opportunity for Guangzhou to implement strategies to manage its parking supply relative to its roadway capacity, plus integrate its parking policies to the overall transportation system.
Practical implications
Emerging cities can learn from other’s experiences. Parking supply affects the decisions people make about how they will travel and this in turn affects congestion, air quality and quality of life. Using smart parking regulations means an end to inadvertently fostering dependency on the car and the start of creating sustainable communities.
Originality/value of chapter
The value of the chapter comes from the way it builds from existing evidence to further understand the challenges of an emerging, fast-growing city.