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Wonders whether, owing to severely restricted access, China’s government policy towards digital communications will remain in a constant state of flux – or will it gain economic benefits without a social penalty? Concludes that China has to link the forces of change to channel and deflect domestic resistance.

This paper sets out to optimize the shape and size of microchannels cooling heat sink, which has been widely used to cool electronic chip for its high heat transfer coefficient and compact structure.

Sequential Quadratic Programming (SQP) method is used to optimize the cross‐section sizes of microchannels. Finite volume method is used to numerically simulate the cooling performance of optimal microchannel cooling heat sink.

The optimized cross‐section shape of microchannel is rectangular, and the width and depth of microchannel is 50 and 1,000 μm, respectively, the number of microchannels is 60, and the corresponding least thermal resistance is 0.115996°C/W. The results show that the heat transfer performance of microchannel cooling heat sink is affected intensively by its cross‐section shape and dimension. The convection heat resistance R_conv between inner surface in microchannels and working fluid has more influence in the total heat resistance. The heat flux of chip is 278 W/cm² and, through the optimization microchannel cooling heat sink, the highest temperature in the chip can be kept below 42°C, which is about half of that without optimizing heat sink and can ensure the stability and reliability of chip.

The convection heat transfer coefficient is calculated approximatively here for convenience, and that may induce some errors.

The optimized microchannels cooling heat sink may satisfy the request for removal of high heat flux in new‐generation chips.

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.

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.

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 R_total is 7.596 K/W, which agrees well with the analysis result of thermal resistance network model.

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.

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.

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.

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.

The convection heat transfer coefficient is calculated approximately here for convenience, and that may induce some errors.

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.

The purpose of this paper is to develop an innovative method of performance appraisal that will be useful for designing a structured training programme.

Employees' performance appraisals are conducted using new approaches, namely data envelopment analysis and an integrated fuzzy model. Interpretive structural modelling is used to design a training programme for employees.

Performance appraisals using data envelopment analysis focus on output enhancement, while an integrated fuzzy model using quality function deployment (QFD) and multi‐attribute decision‐making focuses on input enhancement. For overall and continuous improvement of employees' knowledge, skills and attributes, this composite model provides an in‐depth analysis and also offers a means for designing a structured and effective training programme through interpretive structural modelling.

In data envelopment analysis, the number of employees for performance appraisal should be equal to or greater than three times the selected number of input and output factors. In the integrated fuzzy model, the number of main factors should not exceed seven for pairwise comparison. The size of the QFD matrix should not be more than 30.

The factors selected for appraisal and the method of appraisal should be known by the employees concerned. Consensus among all those concerned is necessary for effective application and utilization of the model.

This model provides a means to increase the knowledge, skills and attributes of employees by adopting a structured approach to designing a training programme for employees of various categories. The approaches used are well‐established and can be applied in many other fields.

In this paper, approaches used for appraisals and designing training programmes are new to this field of study, although they have been successfully proven in many other fields. The results obtained using these methods are useful for helping management to make decisions on training needs, bonuses, incentives and promotions. For the employees, a structured training programme design improves their KSA, quality and standards.

In today’s intense global competition, agility is advocated as a fundamental characteristic for business survival and competitiveness. The purpose of this paper is to propose a practical methodology to achieve and enhance organizational agility based on strategic objectives.

In the first step, a set of key performance indicators (KPIs) of the organization being studied are recognized and classified under the perspectives of balanced scorecard (BSC). Critical success factors are then identified by ranking the KPIs according to their importance in achieving organizational strategic objectives using the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). In the second step, three houses of quality (HOQs) are constructed sequentially to identify and rank the main agile attributes, agile enablers, and improvement paths. In addition, in order to translate linguistics judgments of practitioners into numerical values in building HOQs, fuzzy logic is employed.

The capability of the proposed methodology is demonstrated by applying it to a case of a multi-national food company in Iran. Through the application, the company could find the most suitable improvement paths to improve its organizational agility.

A limited number of KPIs were chosen due to computational and visual constraints related to HOQs. Another limitation, similar to other agility studies, which facilitate decision making among agility metrics, was that the metrics were more industry-specific and less inclusive.

A strong practical advantage for the application of the methodology over directly choosing agility metrics without linking them is that through the methodology, the right metrics were selected that match organization’s core values and marketing objectives. While metrics may ostensibly seem unrelated or inappropriate, they actually contributed to the right areas where there were gaps between the current and desired level of agility. It would otherwise be impossible to choose the right metrics without a structured methodology.

This paper proposes a novel methodology for achieving organizational agility. By utilizing and linking several tools such as BSC, fuzzy TOPSIS, and quality function deployment (QFD), the proposed approach enables organizations to identify the most appropriate agile attributes, agile enablers, and subsequently agile improvement paths.

China is not only the biggest importing country of the raw materials of forest products, but also the biggest exporting country of intermediate and final forest products. The paper aims to discuss these issues.

The authors use the Khandelwal (2010) method and trade data from 2000 to 2014 of bilateral forest products between China and ten main developed countries to evaluate the quality of China’s forestry imports and exports. Subsequently, the influencing factors of product quality are analyzed.

The results show that the current export quality of plywood and fiberboard is decreasing, and the export quality of particleboard and paper products is on the rise. A further study finds that several factors have the positive effects on the quality of forestry exports, including gross domestic product of the importing country, forestry export value of the importing country as well as the number of forestry higher education graduates of the exporting country. Moreover, the study also finds that the status of an Asia-Pacific Economic Cooperation member has a negative effect on the quality of forestry exports, while the distance cost has a negative influence on fiberboard, paper and paperboard.

The study suggests that China needs to strengthen the research and development investment on forest products, and improve the quality of forest products to promote the trade development of forestry exports.

The existing literature has not shown much research regarding the quality of China’s forestry exports through econometric analysis. Therefore, the research results provide new perspective about the influencing factors on China’s forestry trade activities.

With development of the modern electronic and mechanical devices, cooling requirement has become a serious challenge. Innovative heat transfer enhancement methods are generally accompanied by undesirable increase of pressure drop and consequently a pumping power penalty. The current study aims to present a novel and easy method to manufacture a mini heat sink using porous fins and magnetite nanofluid (Fe₃O₄/water) as the coolant for simultaneous heat transfer enhancement and pressure drop reduction.

A three-dimensional numerical study is carried out to evaluate the thermal and hydrodynamic performance of the mini heat sink at different volume fractions, porosities and Reynolds numbers, using finite volume method. The solver specifications for discretization of the domain involve the SIMPLE, second-order upwind and second order for pressure, momentum and energy, respectively.

Results show that porous fins have a favorable effect on both heat transfer and pressure drop compared to solid fins. Creation of a virtual velocity slip on the channel-fin interfaces similar to the micro scale conditions and the flow permeation into the porous fins are the main mechanisms of pressure drop reduction. On the other hand, the heat transfer enhancement is attributed to the increase of the solid-fluid contact area and the improvement of the flow mixing because of the flow permeation into the porous fins. An optimal porosity for maximum convective heat transfer enhancement is obtained as a function of Reynolds number. However, taking both pressure drop and heat transfer effects into account, the overall heat sink performance is shown to be improved at high of Reynolds numbers, volume fractions and fin porosities.

Thermal radiation and gravity effects are ignored, and thermal equilibrium is assumed between solid and fluid phases.

A maximum of 32 per cent increase of convective heat transfer is achieved along with a maximum of 33 per cent reduction in the pressure drop using porous fins and ferrofluid in heat sink.

This article will select 25 years of subdivided data to perform Kaplan–Meier survival analysis on the export trade relations of Chinese wooden flooring, use discrete-time cloglog models to analyze influencing factors, use logit and probit models to test the robustness, and try to systematically reveal the duration of China's wood flooring export trade and its influencing factors.

This study used Kaplan–Meier survival function estimation method. In the survival analysis, survival function and hazard rate function are often used to characterize the distribution of survival time.

The continuous average export time of China's wooden flooring is relatively long, about 14 years. China's wooden flooring has a negative time dependency. After the export trade exceeds the threshold value of 15 years, the failure rate of trade greatly decreases, which has a “threshold effect.” Gravity model variables have a significant impact on the duration of China's wooden floor export.

Studying the duration of forest products trade is of great significance for clearing deep-level trade relations and promoting sustainable development of forest products trade.

This article's purpose is to examine the effect of a Classification-Based Forest Management (CFM) program on farmers' income and determine whether its effect varies with the degree of farmers' concurrent occupations.

The authors use representative panel survey data from Longquan to explore the welfare effects of CFM on farmers. The analysis uses differences-in-differences with propensity score matching (PSM-DID) estimation techniques to deal with endogeneity problems when farmers make the decision to participate in CFM.

The results show that CFM has a positive effect on part-time forestry households (where forestry income accounts for between 5 and 50% of total income). In contrast, it has a negative impact on full-time forestry households (forestry income accounts for more than 50%), and no clear effect on nonforestry households whose forestry income is less than 5%. This research also shows that the positive effect of CFM on farmers' total income is mainly due to increase of off-farm income driven by CFM, while the negative effects consist of CFM's reduction of forestry income.

The extent of CFM's economic benefits to farmers is uncertain and largely unexplored. This paper analyzes the impact of CFM on income structure to explore the mechanisms explaining its effects on farmers' income. There are still challenges in ensuring the reliability and accuracy of CFM assessment. This paper collected natural experimental data and used the estimation technology of PSM-DID to solve the possible endogeneity problems.