Shao Baodong, Wang Lifeng, Li Jianyun and Cheng Heming
The purpose of this paper is to show how, with a view to the shortcomings of traditional optimization methods, a multi‐objective optimization concerning the structure sizes of…
Abstract
Purpose
The purpose of this paper is to show how, with a view to the shortcomings of traditional optimization methods, a multi‐objective optimization concerning the structure sizes of micro‐channel heat sink is performed by adaptive genetic algorithm. The optimized micro‐channel heat sink is simulated by computational fluid dynamics (CFD) method, and the total thermal resistance is calculated to compare with that of thermal resistance network model.
Design/methodology/approach
Taking the thermal resistance and the pressure drop as goal functions, a multi‐objective optimization model was proposed for the micro‐channel cooling heat sink based on the thermal resistance network model. The coupled solution of the flow and heat transfer is considered in the optimization process, and the aim of the procedure is to find the geometry most favorable to simultaneously maximize heat transfer while obtaining a minimum pressure drop. The optimized micro‐channel heat sink was numerically simulated by CFD software.
Findings
The results of optimization show that the base convection thermal resistance contributes to maximum the total thermal resistance, and base conduction thermal resistance contributes to least. The width of optimized micro‐channel and fin are 197 and 50 μm, respectively, and the corresponding total thermal resistance of the whole micro‐channel heat sink is 0.838 K/W, which agrees well with the analysis result of thermal resistance network model.
Research limitations/implications
The convection heat transfer coefficient is calculated approximately here for convenience, and that may induce some errors.
Originality/value
The maximum difference in temperature of the optimized micro‐channel cooling heat sink is 84.706 K, which may satisfy the requirement for removal of high heat flux in new‐generation chips. The numerical simulation results are also presented, and the results of numerical simulation show that the optimized micro‐channel heat sink can enhance thermal transfer performance.
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Baodong Shaoi, Lifeng Wang, Jianyun Li and Zhaowei Sun
The purpose of this paper is to optimize the configuration sizes of micro‐channel cooling heat sink using the thermal resistance network model. The optimized micro‐channel heat…
Abstract
Purpose
The purpose of this paper is to optimize the configuration sizes of micro‐channel cooling heat sink using the thermal resistance network model. The optimized micro‐channel heat sink is simulated by computational fluid dynamics method, and the total thermal resistance is calculated to compare with that of thermal resistance network model.
Design/methodology/approach
Taking the thermal resistance and the pressure drop as goal functions, a multi‐objective optimization model was proposed for the micro‐channel cooling heat sink based on the thermal resistance net work model. The Sequential Quadratic Programming procedure was used to do the optimization design of the structure size of the micro‐channel. The optimized micro‐channel heat sink was numerically simulated by computational fluid dynamics (CFD) software.
Findings
For the heat sink to cool a chip with the sizes of L × W = 2.5 mm × 2.5 mm and the power of 8 W, the optimized width and height of the micro‐channel are 154 μm and 1,000 μm, respectively, and its corresponding total thermal resistance is 8.255 K/W. According to the simulation results, the total thermal resistance of whole micro‐channel heat sink Rtotal is 7.596 K/W, which agrees well with the analysis result of thermal resistance network model.
Research limitations/implications
The convection heat transfer coefficient is calculated approximatively here for convenience, and that may induce some errors. Originality/value –The maximum difference in temperature of the optimized micro‐channel cooling heat sink is 59.064 K, which may satisfy the requirement for removal of high heat flux in new‐generation chips.
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Xin Feng, Xu Wang and Mengxia Qi
In the era of the digital economy, higher demands are placed on versatile talents, and the cultivation of students with innovative and entrepreneurial abilities has become an…
Abstract
Purpose
In the era of the digital economy, higher demands are placed on versatile talents, and the cultivation of students with innovative and entrepreneurial abilities has become an important issue for the further development of higher education, thus leading to extensive and in-depth research by many scholars. The study summarizes the characteristics and patterns of dual-innovation education at different stages of development, hoping to provide a systematic model for the development of dual-innovation education in China and make up for the shortcomings.
Design/methodology/approach
This paper uses Citespace software to visualize and analyze the relevant literature in CNKI and Web of Science databases from a bibliometric perspective, focusing on quantitative analysis in terms of article trends, topic clustering, keyword co-linear networks and topic time evolution, etc., to summarize and sort out the development of innovation and entrepreneurship education research at home and abroad.
Findings
The study found that the external characteristics of the literature published in the field of bi-innovation education in China and abroad are slightly different, mainly in that foreign publishers are more closely connected and have formed a more stable ecosystem. In terms of research hotspots, China is still in a critical period of reforming its curriculum and teaching model, and research on the integration of specialization and creative education is in full swing, while foreign countries focus more on the cultivation of students' entrepreneurial awareness and the enhancement of individual effectiveness. In terms of cutting-edge analysis, the main research directions in China are “creative education”, “new engineering”, “integration of industry and education” and “rural revitalization”.
Originality/value
Innovation and entrepreneurship education in China is still in its infancy, and most of the studies lack an overall overview and comparison of foreign studies. Based on the econometric analysis of domestic and foreign literature, this paper proposes a path for domestic innovation and entrepreneurship education reform that can make China's future education reform more effective.
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Yijing Li, Nan He, Huimin Li, Ziqi Liu and Jianyun Qi
The purpose of this paper is twofold: first, determining which factors critically influence asymmetrical trust behaviors in construction projects within the Chinese context;…
Abstract
Purpose
The purpose of this paper is twofold: first, determining which factors critically influence asymmetrical trust behaviors in construction projects within the Chinese context; second, proposing corresponding measures to deal with the asymmetrical behaviors of both the owner and the contractor promoting cooperative relationships among participants in construction organizations.
Design/methodology/approach
A theoretical model was developed and a questionnaire survey was conducted with 183 professionals. The data collected were analyzed by the structural equation modeling (SEM) technique.
Findings
The results identified six critical factors influencing trust asymmetry behavior in construction projects. The power imbalance, information asymmetry and cognitive difference have a positive influence on both upward-trust behavior and downward-trust behavior in the construction organization, while the competence, performance capacity and relationship satisfaction have negative effects.
Research limitations/implications
This paper based on the assumption that trust asymmetry behavior has a negative impact on project performance, which should be further studied. Besides, future research may carry out a comparative analysis among the trusting relationships and behavior of different participants dynamically.
Originality/value
This paper contributes to the literature in three aspects. First, the factors influencing trust behavior in project organization have been identified for the first time. Second, a comprehensive view of trust asymmetry behavior has been theorized by SEM method. Third, the result bridges the existing gap caused by the lack of empirical evidence to understand the genetic mechanisms of trust asymmetry behavior in the construction industry.
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This article develops a benefit curve and a cost curve that relate the strength of a CEO’s social tie to its benefits and costs respectively, and thereby develops a cost-benefit…
Abstract
Purpose
This article develops a benefit curve and a cost curve that relate the strength of a CEO’s social tie to its benefits and costs respectively, and thereby develops a cost-benefit framework for understanding the strengths of CEO social ties. In particular, this framework helps address the basic, yet largely unanswered questions of why one tie is stronger than another and why a CEO utilizes social ties to a greater extent in one context than in another.
Design/methodology/approach
As a conceptual paper, this article develops a cost-benefit framework for understanding the strengths of CEO social ties.
Findings
This article suggests an important shift of research focus and a different way of thinking regarding tie strength. Specifically, it suggests that the more fundamental question might not be whether a social tie is beneficial or one tie is more beneficial than another, but rather what its optimal strength is, given the underlying relational factors such as resource dependence and demographic similarity. Relatedly, the question might not be whether a CEO’s level of utilization of social ties has a more positive effect on firm performance in one context than in another, but rather what the optimal level of utilization is, given the contextual factors such as environmental uncertainty.
Originality/value
This article addresses a widely accepted, yet potentially misleading understanding of the relationship between a tie’s strength and its benefits (i.e. the strength of weak ties argument). By doing so, it develops a benefit curve that integrates into a coherent, parsimonious function three seemingly conflicting key ideas in the literature (i.e. the overall notion that social ties are beneficial, the strength of weak ties argument, and the liability of strong ties argument). Relatedly, it develops a coherent framework for understanding the strengths of CEO social ties.
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Jianyun Hou, Xuexi Huo and Runsheng Yin
The purpose of this paper is to explore the impact of using computers to obtain information on the farm household’s production and consumption based on a field survey of farm…
Abstract
Purpose
The purpose of this paper is to explore the impact of using computers to obtain information on the farm household’s production and consumption based on a field survey of farm households in the northern China.
Design/methodology/approach
The most important methods applied are instrumental variable (IV) method and propensity score matching (PSM) method. Estimators of IV, PSM and nearest neighborhood matching approaches are considered together to check the robustness of empirical results.
Findings
This paper careful impact evaluation results suggest that the use of computer not only improves the size of arable land rented in but also reduces family labor input intensity and the probability of selling agricultural outputs at farm-gate markets. Moreover, it also stimulates transportation, garment, housing and insurance expenditures per capita.
Research limitations/implications
The database of this research comprises cross-section data, which does not support a cross-time comparison.
Practical implications
These results imply that it is vital to expand the coverage of computer use in rural areas. This may suggest that the importance of improving computer access is crucial for stimulating rural consumption increase. Furthermore, the need for the expansion of internet network coverage in western areas is also of importance.
Originality/value
First, the authors directly estimate computer usage impacts on a broader range of production and consumption indicators by including land-relative investments, variable investments, labor input and household’s expenditure and provide rigorous impact evaluations on the impact of access to computer. Second, the authors use IV and PSM methods to correct self-selection bias, going beyond the single equation approach in other studies. This enables us to identify the causal relationship between computer usage and farmer’s production and consumption decisions.
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Urban planning is the blueprint for the development of urban construction and the basis for management of a city. The urban planning of China’s high-speed modernization has…
Abstract
Urban planning is the blueprint for the development of urban construction and the basis for management of a city. The urban planning of China’s high-speed modernization has encountered many bottlenecks, and the gap between the daily living needs of residents and the urban planning objectives has attracted particular attention. Harmonious development between man and nature is necessary to build a harmonious society, and urban planning that is close to the needs of residents and more humanized has become the main goal of urbanization. In this paper, urban planning of Zhuhai City was studied for one year. Zhuhai focuses on building transport hub, industrial layout, and urban development in three major patterns. Many problems in the planning and management of Zhuhai City were encountered in the past, because the plans are only heavy concepts that ignore implementation and lack of comprehensive survey. Based on the concept of communication planning, the main features of the public participation in the urban planning model through modern mass media may be suitable for achieving the objectives and satisfying public needs. Urban planning and decision-making in Zhuhai City in recent years are evaluated by SWOT method. Future plans of Zhuhai City are discussed.
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Gangling Hou, Yu Liu, Meng Li, Menghan Sun, Feng Sun, Xiuyun Zhu, Rong Pan and Dongyu Zhang
In recent years, a new type of double-layered containment structure of nuclear power plant has been built in China, named ACP1000 NNP. This paper aims to propose a new method to…
Abstract
Purpose
In recent years, a new type of double-layered containment structure of nuclear power plant has been built in China, named ACP1000 NNP. This paper aims to propose a new method to mitigate the seismic responses of this type of the structure.
Design/methodology/approach
The new base isolation structure (BIS)- tuned mass damper (TMD) structure was proposed and implemented only by modifying the connection between various components of NPPs, and the application of this concept design in ACP1000 was skillfully realized.
Findings
The new structure adopts the combination of structural form and function, adopts appropriate amplification of the seismic response of the secondary component, possesses advantages in explicit damping mechanism, good damping effect, robustness of seismic structures, simple implementation process, etc., and meets the special seismic safety requirements of the NPPs.
Originality/value
This seismic and hazard mitigation and BIS-TMD structure can avoid the risk of ACP1000 accidents caused by horizontal earthquakes.
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Yafei Zhang and Li Chen
The purpose of this study is to explore possible factors leading to a successful mediation in Chinese mediation shows. In China, media always play an indispensable role in…
Abstract
Purpose
The purpose of this study is to explore possible factors leading to a successful mediation in Chinese mediation shows. In China, media always play an indispensable role in information dissemination, morality advocacy and policy explanation.
Design/methodology/approach
This paper employed content analysis of 166 episodes of one representative mediation show, Gold Medal Mediation, and regression technique in data analysis.
Findings
Results of ordinal regression suggested that “secret talking”, rather than transparency, between disputants had significant influence on successful mediation. Function of mediators is limited in reaching full mediation. The effective factors leading to full mediation include compromise of rights, secret talking, attitude of the observer cohort. It suggests that the role of mediator is limited, rather than being over-exaggerated, in successful mediation. The successful mediation is largely dependent on disputants’ motivations. Additionally, “compromise of rights” by disputants is a key factor in solving disputes.
Research limitations/implications
Findings of this study revealed the role of Chinese mediation shows in propagating mediation in contemporary Chinese society and supporting upheld morality values. Due to the nature of the chosen mediation show, some disputes take more than one episode to solve. However, this study looks at each episode without considering the integrity of the dispute. That is, if the disputes take two episodes, the coder codes the two episodes as two separate disputes instead of looking at it as one dispute.
Originality/value
By exploring various aspects of mediations shows, including the role of mediators, disputants and a cohort of observers, this study can both explicitly show predicted factors to successful mediations on the shows, and can implicitly examine the power and perceived justification of mediation in contemporary China via media.
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Jiahao Wang, Guodong Xia, Ran Li, Dandan Ma, Wenbin Zhou and Jun Wang
This study aims to satisfy the thermal management of gallium nitride (GaN) high-electron mobility transistor (HEMT) devices, microchannel-cooling is designed and optimized in this…
Abstract
Purpose
This study aims to satisfy the thermal management of gallium nitride (GaN) high-electron mobility transistor (HEMT) devices, microchannel-cooling is designed and optimized in this work.
Design/methodology/approach
A numerical simulation is performed to analyze the thermal and flow characteristics of microchannels in combination with computational fluid dynamics (CFD) and multi-objective evolutionary algorithm (MOEA) is used to optimize the microchannels parameters. The design variables include width and number of microchannels, and the optimization objectives are to minimize total thermal resistance and pressure drop under constant volumetric flow rate.
Findings
In optimization process, a decrease in pressure drop contributes to increase of thermal resistance leading to high junction temperature and vice versa. And the Pareto-optimal front, which is a trade-off curve between optimization objectives, is obtained by MOEA method. Finally, K-means clustering algorithm is carried out on Pareto-optimal front, and three representative points are proposed to verify the accuracy of the model.
Originality/value
Each design variable on the effect of two objectives and distribution of temperature is researched. The relationship between minimum thermal resistance and pressure drop is provided which can give some fundamental direction for microchannels design in GaN HEMT devices cooling.