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This paper aims to investigate and prepare the composite polyurea greases with excellent thermal stability and tribological properties.

In this paper, composite Ba-based (Ba, barium) tetra-polyurea lubricating greases were prepared with two different methods: mixing Ba-based gelatinizer and tetra-polyurea gelatinizer by a physical method; and introducing barium carboxylate into tetra-polyurea molecules by a chemical method. The properties of the products, such as heat stability, water resistance and friction performance, were analyzed with thermogravimetry, water-resistance test and four-ball friction test.

The results indicated that the products obtained by chemically introducing barium carboxylate into tetra-urea molecules showed better elevated temperature tribological properties, and the disadvantages of the polyurea greases with high temperature hardening were also obviously improved. The cone penetration rate at 180°C for 24 h is only 3 per cent. The friction coefficient can be decreased to 0.44 and the last non-seizure load value was increased from 560 N to 1,120 N without any other additives.

The research is significant because the prepared composite grease showed excellent performances, such as the outstanding thermal stability, water resistance and excellent extreme pressure and anti-wear properties, which may be widely applied in steel, metallurgy, bearings and other industrial fields.

The purpose of this paper is to investigate the food price inflation convergence across countries and regions. This study aims to identify the key drivers for food price inflation across countries and regions.

We test whether the international food price inflations are converging over time using the log t convergence test and clustering analysis. These inflation data are collected from the Food and Agriculture Organization of the United Nations.

The test results suggest that there is little evidence of overall convergence. Then we utilize a clustering algorithm and the results support that there is strong evidence of multiple convergence clubs. In addition, we examine the transition path of the various convergence and find that social stability regulation together with economic conditions are important determinants of convergence club membership.

First off, local conflict and economic environment result in food supply and prices, but this study is limited to the dynamics of prices.

Food prices inflations are not converging to single common price inflation, but there exist subgroups of countries or regions within which food price inflation tends to converge. These groupings tend to be related to the economic development and social stability of countries and regions.

The authors believe that any analysis of food price inflations that does not consider the political environment and economic conditions dynamics will likely be omitting important components of food price dynamics.

This study uses a unique data set covering 198 countries and regions and provides a comprehensive analysis of international food price inflation convergence identifying the key drivers of convergence club membership.

User value co-creation behaviors are crucial for the sustainable development of Virtual Brand Communities. This research, grounded in social exchange theory, investigates the impact of community satisfaction and identification on customer value co-creation behaviors and further explores how the reciprocity norm moderates these relationships.

Our research data were collected from users across multiple brand communities, totaling 481 survey responses. Structural equation modeling was performed to test the research hypotheses.

These results provide in-depth insights into the nexus between user-community relationships and customer value co-creation behaviors. While community satisfaction and identification positively influence co-creation, their effects vary across different value co-creation behaviors. Notably, the reciprocity norm within the community dampens the relationship between community satisfaction and value co-creation behaviors.

Unlike previous studies focusing on customer value co-creation behaviors, our research emphasizes social exchange, unveiling the mechanisms behind customer value co-creation. Our findings not only enrich the body of knowledge on customer value co-creation but also deepen our understanding of online collective behavior and knowledge sharing, offering valuable insights for the development of virtual communities.

The debate over differences in the behaviors of firms facing globalization is ongoing. This study examines whether globalization impacts the behavior of family firms and if this influence differs between family and non-family firms.

Drawing on panel data from the Amadeus database on 62 family firms and 98 non-family firms in Europe, the authors employ panel vector autoregression estimation and the Wald test of Granger causality to verify our conjecture. Additional impulse response functions and the forecast error variance decomposition technique were applied to illustrate complementary shock dynamics. Additionally, the KOF globalization index is used as a proxy for globalization.

The results show that globalization visibly impacts family and non-family firms, but the polarity and extent of the effect are different. The authors demonstrate that family firms are in a more favorable position regarding globalization and are less vulnerable to the adverse effects of the globalization process. In contrast, non-family firms fare worse, generating adverse effects. Non-family firms take a more open stance toward globalization than family firms' more conservative behaviors.

Of course, there are some limitations to the work presented in this paper. On the one hand, the authors’ data span only ten years due to data limitations. This causes the generalizability of the results to be hindered. Therefore, the authors encourage scholars to collect more time series data to increase confidence in the empirical results in future studies. On the other hand, the selection of proxy indicators concerning family firm behavior is mainly focused on financial and employment facets. A multidimensional selection of indicators could make the findings of this study more convincing. Despite its limitations, the study certainly adds to the authors’ understanding of its behavior and globalization activities.

The authors’ findings have twofold theoretical and practical implications, as they highlight the necessity of developing specific policies aimed at reducing the gap between family and non-family facing globalization and promoting sustainable operations of non-family firms. Although family firms tend to be more frugal and conservative in their overall decision-making, it should be acknowledged that stockholder and stakeholder interest-oriented corporate management policies have made them more capable of steadily improving corporate performance in the sweep of globalization.

To this end, this study deepens the authors’ understanding of the theory of global governance of family firms. It also provides possible paths and directions for future theoretical research on family firms. Globalization affects both family and non-family firms, but our results suggest that family firms are better able to withstand the adverse effects of globalization shocks and adopt efficient governance paths and strategic thinking to gain a competitive advantage. In this regard, the authors encourage non-family firms to actively learn from family firms' operational practices and systems to achieve better adaptability.

This study provides strong empirical evidence on the effectiveness of family firms' governance patterns and business behavior under globalization. Additionally, this study also reveals that managers can learn from the practical experience of family firms to help them confront business crises and gain a sustainable competitive advantage.

This research aims to improve the performance of rail fastener defect inspection method for multi railways, to effectively ensure the safety of railway operation.

Firstly, a fastener region location method based on online learning strategy was proposed, which can locate fastener regions according to the prior knowledge of track image and template matching method. Online learning strategy is used to update the template library dynamically, so that the method not only can locate fastener regions in the track images of multi railways, but also can automatically collect and annotate fastener samples. Secondly, a fastener defect recognition method based on deep convolutional neural network was proposed. The structure of recognition network was designed according to the smaller size and the relatively single content of the fastener region. The data augmentation method based on the sample random sorting strategy is adopted to reduce the impact of the imbalance of sample size on recognition performance.

Test verification of the proposed method is conducted based on the rail fastener datasets of multi railways. Specifically, fastener location module has achieved an average detection rate of 99.36%, and fastener defect recognition module has achieved an average precision of 96.82%.

The proposed method can accurately locate fastener regions and identify fastener defect in the track images of different railways, which has high reliability and strong adaptability to multi railways.

The purpose of this paper is to examine the effect of ethical leadership on radical and incremental innovation through the mediating roles of tacit and explicit knowledge sharing (KS).

The paper used a quantitative research method and structural equation modeling to test the research hypotheses based on a sample of 365 participants from 115 Vietnamese firms.

The results indicated that ethical leadership is positively related to radical and incremental innovation. In addition, tacit and explicit KS significantly mediate the relationship between ethical leadership and the two types of innovation.

This study is cross-sectional, which limits its ability to control the specific features of the correlations among the factors in the long term.

The findings of this study suggest that leaders should invest in practicing and applying a moral lens to motivate positive KS behaviors of employees and organizational capabilities for innovation.

This study significantly fills gaps in the literature and advances the understanding of how ethical leadership fosters employees’ KS to improve radical and incremental innovation.

The purpose of this paper is to investigate the influence of an employee’s personal creative identity on their innovation behaviour in knowledge-intensive information technology (IT) service provider firms. It further investigates the mediating role of an employee’s creative process engagement (CPE) and the moderating effects of the organizational creative climate on creative identity-innovative behaviour (IB) relationships.

This study follows a quantitative method. Using a multi-item survey instrument, a total of 316 questionnaires were collected from the employees of IT service provider firms in Chittagong, Bangladesh. The collected data were analysed using structural equation modelling, factor analysis and path analysis to test the hypotheses and to assess the moderating and mediating effects of the variables.

The results revealed the significant influence of an employee’s creative personal identity (CPI) on their IB. The mediation analysis revealed that CPE mediates the association between a CPI and IB. The study also found a significant moderating effect of a creative organizational climate between a CPI and CPE.

Based on the premise of the interactionist approach of creativity and role identity theory, this study contributes to the creativity and innovation literature by providing empirical support for the relationship between a personal creative identity, organizational creative culture, CPE and IB in IT service organizations.

This study adopts a distinct model comprising four different variables to investigate an employee’s IB from a multi-level perspective, i.e., a creative identity and CPE at the individual level and a creative climate and IB at the organizational level. This integrated model using predictors from multiple levels supports the theoretical assumption that IB results from the interaction of individual and organizational level factors.

This paper aims to recognize whether government policy supervision or social network platform supervision can effectively promote the control of misconducts of web celebrity brand eWOM marketing and to identify the key factors influencing the unhealthy web celebrity marketing environment.

Theoretical research was employed to develop a practical approach for applying evolutionary game theory to eWOM marketing controlling strategies modeling via dynamic visualization, systematic simulation experiments.

Evolutionary game theory combined with dynamic simulation modeling can provide a formal approach to understanding web celebrity brand eWOM marketing decision-making in social media, which can thus support the control of unhealthy web celebrity marketing environment. The results demonstrate that the reasonable control of social platform control costs may be more effective than the government policy on web celebrity fake brand eWOM marketing behaviors.

The study enriches the research on the management and control of eWOM marketing as well as provides guidance for the sustainable development of the web celebrity economy in social media.

Recent research studies have increasingly suggested leadership as a major antecedent to encourage innovative work behavior among business employees. Empirical studies which investigated the influence of various leadership aspects such as style and ethics on employees' innovative performance and unraveled the mechanism through which leadership exerts its impact on employees' innovative work behavior were restricted. Thus, the purpose of this research was to investigate the relationship between ethical leadership and employees' innovative performance by focusing on the mediating role of two forms of the intellectual capital (IC), i.e. human capital and social capital.

Data for present research were collected through in person administered questionnaire-based survey from the managerial level employees of the targeted sample of the manufacturing firms. Furthermore, due consideration was given while selecting the individuals from R&D departments of these organizations, who were typically involved in knowledge-intensive jobs and where application of intellectual assets was needed.

Ethical leadership was observed as to positively influencing employees' innovative performance. Two forms of IC, i.e. human capital and social capital were observed as playing mediating role in the ethical leadership – employees' innovative performance relationship.

The contemporary research study adds value in the literature of the ethical leadership. The most imperative theoretical contribution of the present research study underlines the psychological process, i.e. IC by which ethical leaders encourage innovative behavior among employees.

The purpose of this paper is to investigate the oscillating trajectory of the paddle of a fin-wheel underwater robot to enhance its propulsion efficiency in water. This robot can be used for underwater detection and military operations.

By studying the propulsion mode of underwater fin-based robots, it is found that such robots periodically generate a large reverse thrust during the swing process, resulting in low propulsion efficiency. Therefore, according to the propulsion characteristics of the oscillating paddle in the underwater environment, the hydrodynamic model and physical constraints of the oscillating paddle are established. Then, the oscillating gait trajectory of the paddle is optimized by the trajectory optimization method. The performance of the optimized trajectory was tested in the simulation environment and the actual underwater environment.

The prototype of the robot was built and tested in a small swimming pool. The research results confirm that the propulsion efficiency of the optimized trajectory is higher than that of the traditional trajectory under the condition of the same amplitude and period. Specifically, the maximum speed of the robot can reach 0.24 m/s when using the optimized trajectory, which is about 50% higher than that before optimization.

The optimized trajectory with the generated impulse as the optimization target is applied to the paddle oscillation, which can improve the thrust impulse generated by the fin-wheel underwater robot during underwater motion, thereby greatly improving the underwater propulsion efficiency and moving speed.