Qing Xu, Jiangfeng Wang, Botong Wang and Xuedong Yan
This study aims to propose a speed guidance model of the CV environment to alleviate traffic congestion at intersections and improve traffic efficiency. By introducing the theory…
Abstract
Purpose
This study aims to propose a speed guidance model of the CV environment to alleviate traffic congestion at intersections and improve traffic efficiency. By introducing the theory of moving block section for high-speed train control, a speed guidance model based on the quasi-moving block speed guidance (QMBSG) is proposed to direct platoon including human-driven vehicles and connected vehicles (CV) through the intersection coordinately.
Design/methodology/approach
In this model, the green time of the intersection is divided into multiple block intervals according to the minimal safety headway. Connected vehicles can pass through the intersection by following the block interval using the QMBSG model. The block interval is assigned dynamically according to the traveling relation of HV and CV, when entering the communication range of the intersection. To validate the comprehensive guidance effect of the proposed model, a general evaluation function (GEF) is established. Compared to CVs without speed guidance, the simulation results show that the GEF of QMBSG model has an obvious improvement.
Findings
Compared to CVs without speed guidance, the simulation results show that the GEF of QMBSG model has an obvious improvement. Also, compared to the single intersection speed guidance model, the GEF value of the QMBSG model improves over 17.1%. To further explore the guidance effect, the impact of sensitivity factors of the CVs’ environment, such as intersection environment, communication range and penetration rate (PR) is analyzed. When the PR reaches 75.0%, the GEF value will change suddenly and the model guidance effect will be significantly improved. This paper also analyzes the impact of the length of block interval under different PR and traffic demands. It is found that the proposed model has a better guidance effect when the length of the block section is 2 s, which facilitates traffic congestion alleviation of the intersection in practice.
Originality/value
Based on the aforementioned discussion, the contributions of this paper are three-fold. Based on the traveling information of HV/CV and the signal phase and timing plans, the QMBSG model is proposed to direct platoon consisting of HV and CV through the intersection coordinately, by following the block interval assigned dynamically. Considering comprehensively the indexes of mobility, safety and environment, a GEF is provided to evaluate the guidance effect of vehicles through the intersection. Sensitivity analysis is carried out on the QMBSG model. The key communication and traffic parameters of the CV environment are analyzed, such as path attenuation, PR, etc. Finally, the effect of the length of block interval is explored.
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Jingyu Yu, Guixia Ma, Wenxuan Ding, Jiangfeng Mao and Jingfeng Wang
China is experiencing tremendous changes of rapid urbanization and aging society. The development of age-friendly communities (AFCs) has been encouraged for improving health and…
Abstract
Purpose
China is experiencing tremendous changes of rapid urbanization and aging society. The development of age-friendly communities (AFCs) has been encouraged for improving health and well-being of older adults. Hence, this study aimed to deepen the understanding of AFCs in China and to investigate the integrated relationships between AFCs and the quality of life (QoL) of older adults, using a large-scale questionnaire survey.
Design/methodology/approach
A questionnaire survey was conducted in Hefei, China, to investigate the complicated relationships between the components of AFCs and the QoL of older adults. Ultimately, 1,383 valid questionnaires were collected from senior respondents aged more than 60 years. Several statistical methods, including reliability analysis, correlation analysis and structural equation modeling (SEM), were adopted to develop an integrated model for AFC components and the QoL of older adults.
Findings
Six AFC components and four older adults' QoL factors were identified. The SEM results revealed integrated relationships between specific AFC components and the QoL of older adults: (1) physical QoL was affected by outdoor spaces, public transportation, housing and community and health services; (2) psychological QoL was predicted by most of the AFC components except community and health services; and (3) environmental QoL and social QoL were both influenced by outdoor spaces, communication and information and community and health services.
Practical implications
In order to enhance the QoL of older adults, it is suggested that outdoor spaces need to be enlarged by fully using the facilities and playgrounds of middle schools and renovating the older buildings. The locations of public transportation stations are recommended to be revised to be within a 5-minute walking distance of senior residents. Improvements to the social environment of AFCs, by increasing the coverage of medical services and creating multiple approaches to recreational activities, are encouraged.
Originality/value
These findings have empirical significance for urban planners and policy-makers in regard to identifying major components of AFCs and understanding the effect of those components on the QoL of older adults.
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Jiangfeng Ye, Yingna Jiang, Bin Hao and Yanan Feng
This study aims to explore the impact of search breadth and depth on corporate entrepreneurship (CE) through the mediating effect of opportunity discovery under the consideration…
Abstract
Purpose
This study aims to explore the impact of search breadth and depth on corporate entrepreneurship (CE) through the mediating effect of opportunity discovery under the consideration of the technological environmental dynamism as a moderating factor.
Design/methodology/approach
This study adopts a quantitative method, collecting 246 questionnaires from high-tech firms in the national industrial park of the Yangtze River Delta zone in China. The authors examine the hypotheses using multiple hierarchical regressions and conduct Sobel and bootstrapping tests to further assess the mediating and moderated mediating effects of the variables.
Findings
The results indicate that both the relationship between search breadth and CE and the relationship between search depth and CE are mediated by opportunity discovery. The authors further show that technological environmental dynamism positively moderates the indirect effect of knowledge search breadth on CE and negatively moderates the indirect effect of knowledge search depth and CE.
Originality/value
This study provides a valuable theoretical framework for entrepreneurship literature by differentiating the effects of search depth and search breadth on the promotion of CE in established firms and pioneers the examination of the mediating role of opportunity discovery and the moderating role of technological environmental dynamism in these links as well.
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Ning Zhang, Xu Haoran, Feng Jiang, Dawei Wang, Peng Chen and Qing Zhang
Based on the theoretical viewpoints of criminal geography and environmental criminology, this research uses spatial multi-criteria decision-making methods. In the process of…
Abstract
Purpose
Based on the theoretical viewpoints of criminal geography and environmental criminology, this research uses spatial multi-criteria decision-making methods. In the process of spatial decision-making and optimization of police resources, researchers fully consider the dynamic application of Geographic Information System (GIS) and the effects of spatial prevention and control.
Design/methodology/approach
Researchers use an integrated method combining Policing Geographic Information System (PGIS) and multi-criteria decision analysis (MCDA). On the one hand, police GIS has an excellent visual data analysis platform and integrated decision support system in data management, spatial analysis, data exploration and regression analysis. On the other hand, through the design of the indicator system, the quantification of indicators, the determination of weights, comprehensive evaluation and sensitivity analysis, MCDA can select the best plan from a large number of alternatives. When joining MCDA, the spatial dimension will bring the research results closer to the real world.
Findings
The study finds that the crime of burglary is affected to a certain extent by the distribution of police forces, the location of police units. Another important finding of this research is the correlation between more precise preventive measures and the crime of burglary.
Originality/value
From a practical point of view, this research would help advance the role of police units and law enforcement agencies in preventing burglary crimes and provide experience for the allocation of regional police resources.
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Jiangfeng Ye, Shunqing Shi and Yanan Feng
This investigation seeks to elaborate on how proactive market orientation (MO) and responsive MO motivate firms to conduct business model innovation (BMI) through the breadth of…
Abstract
Purpose
This investigation seeks to elaborate on how proactive market orientation (MO) and responsive MO motivate firms to conduct business model innovation (BMI) through the breadth of market knowledge search (BMKS) and the depth of market knowledge search (DMKS).
Design/methodology/approach
Based on the survey data of 259 high-tech firms in the industrial parks of the Yangtze River Delta, this study uses multiple hierarchical regressions to examine the hypotheses and conducts Sobel and bootstrapping methods to further test the mediating effects.
Findings
The findings indicate that the positive effects of proactive and responsive MO on BMI are mediated by BMKS and DMKS. It also shows that proactive MO has a greater impact on BMKS than responsive MO, while responsive MO has a stronger impact on DMKS than proactive MO.
Practical implications
Firms with different MOs can choose different types of market knowledge search to promote BMI, which reminds managers to give attention to the importance of bridging MOs with knowledge search strategies in BMI.
Originality/value
This study introduces a constructive theoretical framework by examining the roles of MO and market knowledge search on BMI. The findings reveal that MO as a key initiating factor and market knowledge search as an important conduit play vital roles in the experimental process of BMI and identify the differential effects of proactive and responsive MO on two types of market knowledge search.
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Xin Guo, Jiesong Tu, Zhibin Fan, Baoshuai Du, Hongfei Shang, Jiangfeng An and Dan Jia
Corrosion thinning reduces the effective cross-sectional areas of steel structures and degrades their mechanical properties. This study aims to investigate the relationship…
Abstract
Purpose
Corrosion thinning reduces the effective cross-sectional areas of steel structures and degrades their mechanical properties. This study aims to investigate the relationship between the corrosion thinning of carbon steel for transmission towers and the degradation of its mechanical properties.
Design/methodology/approach
A macroscopic finite element model of a transmission tower was established and then combined with the corrosion thinning and mechanical properties of Q355 steel in different test periods measured in neutral salt spray, SO2 atmosphere and wet heat environments to conduct a finite element simulation of a transmission tower with different corrosion thinning of Q355 steel.
Findings
When the residual thickness of the tower leg angle was reduced to 4.03 mm, the maximum stress solved in the simulation exceeded the yield strength, with the tower already at risk of collapse owing to corrosion failure under extreme conditions of basic wind speed.
Originality/value
This study innovatively utilises transmission tower finite element models and experimental data from mechanical degradation experiments to quantify the relationship between corrosion thinning and the mechanical properties of Q355 steel, ensuring the effective assessment of the mechanical properties of corroded transmission towers.
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Xianwei Liu, Huacong Li, Xinxing Shi and Jiangfeng Fu
The purpose of this paper is to improve the hydraulic efficiency without changing the overall dimension. The blade profile optimization design of the aero-centrifugal pump based…
Abstract
Purpose
The purpose of this paper is to improve the hydraulic efficiency without changing the overall dimension. The blade profile optimization design of the aero-centrifugal pump based on the biharmonic equation surrogate model has been studied.
Design/methodology/approach
First of all, Bezier curves and linear function are used to control the annular angle distribution and the stacking angle of blade profile under the MATLAB platform. Grid independence analysis has been studied to find the finest mesh scheme. After the precision comparison of test data and computation fluid dynamics 15 sets of design parameters are carried out as the boundary condition of the biharmonic equation. The efficiency surrogate model of the biharmonic equation is constructed via iteratively solving of a discrete difference equation. The other two surrogate models of response surface model (RSM) and radial basis function neural network surrogate model (RBFNNSM) are compared with the biharmonic equation surrogate model by the standard of modified complex correlation coefficient R2 and root mean square deviation (RSME). Finally, the artificial fish swarm algorithm has been used to find the global optimal design parameters with the objective function of highest efficiency.
Findings
The results show that the design parameters code conversion method can reduce the number of optimization parameters from five to three, makes the design space become a cube, and compared with RSM and RBFNNSM, the biharmonic equation surrogate model has higher precision with R2 is 0.8958, RSME is 0.1382. The final optimum result of AFSA is at the point of [1 −1 −1]. The internal flow field analysis shows that after optimization the outlet relative velocity becomes more uniform and the wake effect has been significantly decreased. The hydraulic efficiency of the optimized pump is about 59.45 per cent increasing 5.4 per cent compared with a prototype pump.
Originality/value
This study developed a new method to optimize the design parameters of aero-centrifugal pump impeller based on biharmonic equation surrogate model, which had a good agreement with experimental values within just 15 sets of the original design. The optimization results shows that the method can improve the hydraulic efficiency significantly.
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Dujuan Huang, Song Chen, Gupeng Zhang and Jiangfeng Ye
The purpose of this paper is to examine how the organizational forgetting affect innovation performance under the consideration of the environmental turbulence as a moderating…
Abstract
Purpose
The purpose of this paper is to examine how the organizational forgetting affect innovation performance under the consideration of the environmental turbulence as a moderating factor of the analysis framework.
Design/methodology/approach
This study constructs and verifies a moderated mediating model of organizational forgetting to innovation performance, using the exploratory factor analysis and the hierarchical regression analysis based on a survey sample of 320 Chinese companies.
Findings
The organizational forgetting is a critical determinant for improving innovation performance of an enterprise. A more detailed analysis reveals that first organizational forgetting cannot promote organization’s innovation performance without absorptive capacity. Second, the mediating effect of absorptive capacity is more positive when environmental turbulence is higher.
Practical implications
This study provides empirical evidence about the importance of organizational forgetting in the firm innovation.
Originality/value
This paper adds to the existing literature by providing a clear explanation of the impacts of organizational forgetting on innovation performance through a comprehensive empirical study. Contrasting with previous research, this research clarifies the boundary conditions under which organizational forgetting enhances innovation performance. In particular, the authors find that organizational forgetting is not equally positive but instead increases with the level of environmental turbulence.
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Jiangfeng Ye, Yunqiao Wu, Bin Hao and Zusheng Chen
The purpose of this study is to investigate the relationships between two types of informal ties and radical innovation in the context of China’s university spin-offs and the…
Abstract
Purpose
The purpose of this study is to investigate the relationships between two types of informal ties and radical innovation in the context of China’s university spin-offs and the moderating roles of knowledge breadth and depth in such relationships.
Design/methodology/approach
A systematic review of literature on informal ties, internal knowledge base and radical innovation provides the theoretical foundation of the research framework and hypotheses. Using a sample of 158 China’s university spin-offs, the authors conduct a regression analysis on the theoretical framework and hypotheses.
Findings
The results show that business and university ties are positively related to radical innovation. Moreover, the effects of business and university ties on radical innovation are contingent on knowledge breadth and depth in opposite ways. In particular, the positive effect of business ties on radical innovation depends significantly on internal knowledge depth rather than on knowledge breadth, and the positive effect of university ties on radical innovation will be affected by internal knowledge breadth rather than knowledge depth.
Practical implications
Managers of university spin-offs must examine informal ties they already have and identify their nature, content and embedded advantages and promptly adjust their strategy of informal ties to adapt to their firms’ internal knowledge base.
Originality/value
This study highlights the positive role of managers’ personal connections with different external parties in facilitating radical innovation and advances the understanding of informal ties by proposing that the effects of informal ties on radical innovation are contingent on a firm’s internal knowledge base in the context of China’s university spin-offs.
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Trilochana Dash and Chandan Kumar Sahoo
This study aims to understand the relationship between social audit (SA) and sustainable corporate social responsibility (SCSR). Furthermore, this study will investigate the…
Abstract
Purpose
This study aims to understand the relationship between social audit (SA) and sustainable corporate social responsibility (SCSR). Furthermore, this study will investigate the mediating effect of corporate social innovation (CSI) on the relationship between SA and SCSR and the moderating impact of community participation (CP) on the relationship between CSI and SCSR.
Design/methodology/approach
This research was conducted in Odisha, a state in India, with 448 respondents and a response rate of 89%. The convenience sampling technique was used, and questionnaires were prepared in English and translated into regional languages during data collection. Psychological separation and Harman’s single-factor test were used to avoid common method bias. Exploratory factor analysis and confirmatory factor analysis were performed step by step to validate the proposed model.
Findings
The current study indicates that SA positively impacts SCSR. Findings from the analysis show that CSI partially mediates the relationship between SA and SCSR. Furthermore, this study indicates that CP moderates the relationship between CSI and SCSR.
Originality/value
This study is one of its kind concerning the variables considered, and it can work as a stepping stone for upgrading the delivery mechanism for corporate social responsibility (CSR) programs, which can solve the fundamental problems faced in society more effectively. It will provide new paths for future researchers to study in the area of audit and CSR.