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This paper aims to study the friction layer and tribological property of polyimide (PI)–matrix composites under different friction speeds.

Friction tests were conducted under friction speeds ranging from 20-120 km/h and pressure of 0.57 MPa by a pin-on-disk tribometer.

The results indicate that the friction coefficient decreases with the increasing of the friction speed. Under different friction speeds, the structure of the friction layer and debris are different, which affects the actual tribological performance of the composites. At low friction speed, the morphology of the friction layer is mainly particulate. The higher level of clenching action between the friction pair leads to a high friction coefficient, and the morphology of the particles in the particulate zone and the wear debris are mostly equiaxial particles. At high friction speed, the morphology of the friction layer is mainly a compact zone. The reduction of the surface roughness leads to a low friction coefficient. The debris collected on the counter surface at high friction speeds are mostly big sheets, and the morphology of the particles in the particulate zone is mostly rod-like. Controlling the conditions of the disk and the pin can reveal the influence of friction speed on the friction layer. The wear mechanisms at different friction speeds are also discussed.

By controlling the conditions of the disk and the pin to reveal the influence of friction speed on the friction layer, and the evolutions of the friction layer, wear debris were carefully inspected with the aim of demonstrating the relationship between friction speed and wear mechanism of PI–matrix composites.

Corporate entrepreneurship is an important way for organizations to gain competitive advantages and achieve sustainable development. However, few studies pay attention to the influence of CEO strategic leadership on corporate entrepreneurship. Drawing on social identity theory and uncertainty-identity theory, this study aims to investigate whether CEO relationship-focused leadership impacts corporate entrepreneurship through middle managers’ (MMs’) organizational identification and whether the indirect effect is moderated by environmental uncertainty.

Using 192 Chinese samples with 192 firm-level and 716 department-level observations, this study uses multilevel structural equations modeling by Mplus 8.0 to test the theoretical model.

This study finds that CEO relationship-focused leadership positively predicts MMs’ organizational identification and corporate entrepreneurship, and MMs’ organizational identification mediates the relationship between CEO relationship-focused leadership and corporate entrepreneurship. In addition, environmental uncertainty moderates not only the relationship between CEO relationship-focused leadership and MMs’ organizational identification but also the indirect effect of CEO relationship-focused leadership on corporate entrepreneurship through MMs’ organizational identification.

This study enriches the understanding of process and contextualization of CEO strategic leadership influencing on corporate entrepreneurship.

To the best of the authors’ knowledge, this study is among the first to explore the influence of CEO relationship-focused leadership on corporate entrepreneurship.

Ulam is a traditional salad that contains high levels of antioxidants and is commonly consumed in raw form. However, the average ulam consumption among the low-income Malaysian population was only ½ serving daily. Thus, this study aimed to explore the motivators and barriers to ulam consumption among residents of low-cost housing areas (household income RM4849 or $1015.50) in Kuala Lumpur, Malaysia.

Six focus group discussions were conducted with 27 Malay residents aged 18–59 years in Kuala Lumpur, Malaysia. The researchers asked the participants a series of semi-structured questions. All the interviews were audio-recorded and transcribed verbatim. Two researchers coded the transcripts independently, and several themes were identified. The data were analysed using Nvivo version 12 software.

Three main factors for ulam consumption were identified in this study: personal, environmental and behavioural. The motivators and barriers were identified based on nine main themes and 16 sub-themes.

The results of this study identified potential areas for an effective intervention to increase ulam intake among residents in low-cost housing areas.

This work has the potential to identify the factors that have an impact on consumers' ulam preferences to help fulfil daily vegetable recommendations.

The associations between legume consumption and cardiovascular events (CVEs) have extensively been studied. However, there are few studies that considered longitudinal association between legume consumption (with repeated measurements across time) and CVEs in low-income countries where legume consumption is lower than the Western countries. The authors aimed to investigate the long-term longitudinal relationship between soybean, non-soybean and overall legume consumption and CVEs using repeated measures of legumes and time-varying confounders in a cohort study of the general population.

The current study was performed within the framework of the Isfahan cohort study among 5,432 healthy participants. The participants were followed-up for fatal and non-fatal myocardial infarction, unstable angina, fatal and non-fatal stroke and sudden cardiac death for 13 years. Dietary intake was evaluated using a validated food frequency questionnaire in 2001, 2007 and 2013. The hazard ratios (HRs) and 95% confidence intervals (CI) for CVEs between categories of soybean, non-soybean and overall legumes intake were examined using marginal Cox's regression analysis.

Long-term consumptions of overall legumes more than three times per week and non-soybean three times or more per week compared with those who had less than once a week were associated with 19.5% (HR = 0.805, 95% CI: 0.650,0.998; p < 0.048) and a 18.5% (HR = 0.815, 95% CI: 0.673, 0.988; p < 0.037) lower risk of CVEs in the general population, respectively. However, our findings revealed no significant reduction in CVEs following a higher intake of soybeans.

In the long run, even modest consumption of legumes, but not soybeans alone, can be effective to reduce CVEs risk in a low-income population. Further studies are warranted to confirm our results in other populations, examine the associations by the type of cardiovascular events and determine any possible threshold effects in this regard.

This paper comes to the point from the tax competition of local government in investment promotion and capital introduction. This paper aims to empirically examine the internal mechanism of enterprises obtaining land resources from local government and its resulting equity investment increase and economic consequences of overinvestment.

The data of China’s A-share listed companies from 2007 to 2014 were used to test the relationship between the increase in enterprise equity investment and the acquisition of land resources and overinvestment. The descriptive statistics, correlation analysis and least squares linear regression were used to solve the above question.

One of the reasons for the enterprise equity increase is to obtain scarce land resources. The enterprise acquisition for land resources leads to overinvestment. The equity investment increase from obtaining land resources will further stimulate enterprise group to overinvest.

The authors could not get the actual data of land that subsidiaries have obtained directly. In this research, the authors get the data using consolidated statements and subsidiary statements indirectly.

The results make contributions to the influencing factors and economic consequence of the enterprise investment structural deviation.

It provides reference to optimize the “interaction” relationship between government and enterprises.

It identified the “dual-channel” conduction mechanism between land resource acquisition and enterprise overinvestment.

The purpose of this paper is to examine Chinese consumers’ attitudes toward genetically modified (GM) foods and the impact that consumers’ trust in different actors – GM scientists, non-GM scientists or individuals, the government and the media, has on their attitudes.

Consumers in Beijing were surveyed about their attitudes toward GM foods and their trust in different actors. The surveys were conducted from June to July of 2015. The sample size is 1,460 people. Given the potential endogeneity of trust variable, bivariate probit models are employed to estimate the impact of trust in different actors on consumers’ attitudes.

The results show that 55 percent of the Chinese consumers are opposed to GM foods and nearly 60 percent do not trust GM scientists. In total, 42 percent of Chinese consumers trust in the government and 39 percent trust the non-GM scientists or individuals. Around 35 percent of consumers believe the misinformation on GM technology that were provided by the media. Trust in the GM scientists and trust in the government have a significant positive impact on consumers’ acceptance of GM foods while trust in the non-GM scientists or individuals and believing the misinformation have a significant negative effect on the acceptance. Nearly 70 percent of Chinese consumers acquired information about GM food safety from the internet or via WeChat. Consumers who acquired GM technology information from the internet or via WeChat are less likely to embrace GM foods than those who obtain information from other sources.

Consumer trust plays a crucial role to accept biotech products in the market and it is crucial for producers, policy makers and consumers to have faith in new biotech products. The results of this study suggest that the government and GM scientists should make more effort to gain the trust and support of consumers, while the media should provide objective reports on GM products based on scientific evidence.

The aim of this paper is to solve the problem of low accuracy of traditional fatigue crack growth (FCG) prediction methods.

The GMSVR model was proposed by combining the grey modeling (GM) and the support vector regression (SVR). Meanwhile, the GMSVR model parameter optimal selection method based on the artificial bee colony (ABC) algorithm was presented. The FCG prediction of 7075 aluminum alloy under different conditions were taken as the study objects, and the performance of the genetic algorithm, the particle swarm optimization algorithm, the n-fold cross validation and the ABC algorithm were compared and analyzed.

The results show that the speed of the ABC algorithm is the fastest and the accuracy of the ABC algorithm is the highest too. The prediction performances of the GM (1, 1) model, the SVR model and the GMSVR model were compared, the results show that the GMSVR model has the best prediction ability, it can improve the FCG prediction accuracy of 7075 aluminum alloy greatly.

A new prediction model is proposed for FCG combined the non-equidistant grey model and the SVR model. Aiming at the problem of the model parameters are difficult to select, the GMSVR model parameter optimization method based on the ABC algorithm was presented. the results show that the GMSVR model has better prediction ability, which increase the FCG prediction accuracy of 7075 aluminum alloy greatly.