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The traction behaviours of lubricating oil significantly affect the stability and lubrication regime of aviation high-speed ball bearings. Rolling elements will slide at a low traction force (TF). Therefore, traction behaviours need to be studied, and a fitting expression for traction curves to rapidly calculate the traction coefficient (TC) should be developed.

The traction behaviours of an aviation lubricating oil were studied in severe operating conditions with a self-designed two-disc testing rig. Based on the least squares method and the Levenberg–Marquardt theory, a rapid calculation expression was developed by fitting the obtained traction curves. The correction of this expression was experimentally verified by comparing the TCs under different operating conditions. This expression was also used to modify the commonly accepted quasi-dynamic model of rolling bearings.

An increase of the load led to an increase in the TC. In comparison, the temperature and entrainment speed showed inverse effects. The proposed expression exactly predicted the trend of the experimentally acquired traction curve. The calculation with the modified dynamic model showed that the action of the TF on a single rolling element varied and that the temperature increase of the outer raceway is higher than the inner raceway, which is caused by the TF and relative sliding speed between the elements and raceways.

The proposed fitting expression is able to simplify the TC calculation of synthetic aviation lubricating oil in practical engineering applications. This paper can provide an important reference for the traction behaviour of synthetic aviation lubricating oil under severe conditions and assist with its rapid calculation and practical application in engineering.

Organizations use enterprise social media (ESM) platforms to operate, function, and develop. However, the effectiveness of the use of ESM is inconclusive. This study aims to explore the mechanism and boundary conditions of the relationship between employee ESM use and job performance.

This study uses a 2-wave survey design, with a final sample of 481 employees from a large automobile company.

The results indicate that ESM use is beneficial and detrimental to job performance. On the one hand, ESM use is positively related to work overload, decreasing job performance. On the other hand, ESM use is positively associated with informational support, increasing job performance. A mediation test revealed that both work overload and informational support mediate the relationship between ESM use and job performance. Furthermore, job autonomy weakens the positive relationship between ESM use and work overload, but strengthens the positive relationship between ESM use and informational support.

This study provides a more balanced view of how ESM use influences job performance by demonstrating the opposing mediating roles of work overload and informational support. Further, this study fills a research gap by considering job characteristics when examining the boundary conditions of ESM use. Third, this study validates the generalization of the job demands-resources model in social media research.

Organizational citizenship behaviors for the environment (OCBEs) represent a crucial element of environmental sustainability for a wide range of organizations. However, the leadership mechanisms underlying OCBEs are as yet unexplored, particularly regarding the delivering megaprojects. The paper aims to investigate how transformational leadership (TFL) and transactional leadership (TSL) styles shape the environmental commitment (EC) of subordinates, motivating OCBEs in megaprojects.

Partial least squares modeling and hierarchical regression were performed on data obtained from 140 experts who have been involved in megaprojects.

Both TFL and TSL styles are effective in motivating OCBEs, although the EC of subordinates partially mediates these relationships. The power distance (PD) orientation significantly moderates the relationship between TFL and OCBEs, with the relationship being more positive when the PD of subordinates is lower. Unexpectedly, a collectivist orientation (CO) was found to elevate the effect of TSL but weaken the effect of TFL.

The mixed and contradictory findings regarding TFL and TSL styles are reconciled in the current study by integrating the contextual factors of PD and CO. The findings of the study shed new light on “playing the cards right” when using the leadership practices, i.e. how leadership can be better leveraged to cultivate subordinates' OCBEs. They also provide targeted guidance for shaping contextual factors to increase the environmental sustainability of megaprojects.

When a vehicle passes through a long highway tunnel, the smoke it discharges accumulates in the tunnel. High smoke concentration has an important influence on the driver’s health and driving safety. The use of numerous jet fans to diffuse the smoke causes excessive energy consumption, so it is of significant practical value to design suitable tunnel ventilation.

The study is based on the continuum hypothesis, incompressible hypothesis, steady flow hypothesis and similar hypothesis of gas in a long highway tunnel. These hypotheses calculate the gas emissions and wind demand in a long highway tunnel given the deployment of the jet fan program.

This program selects each of the two 1120-type jet machine group and sets up 13 groups; each group has an interval of 184.5 m in the end. The analysis of air test results when the tunnel is in operation shows that CO and smoke concentrations meet the design requirements, which can provide reference for a similar engineering design later.

At present, a highway tunnel is recognized at home and abroad by means of clearance of longitudinal ventilation, which is 2,000 m. In view of this, this paper is based on the theory of longitudinal jet ventilation of a highway tunnel, whose length is more than 2,000 m, to calculate the ventilation and apply it to a tunnel’s ventilation design.

The recent rise of economic nationalism intensifies consumers' patriotic attitudes toward goods or services and thus encourages enterprises to build patriotic brand images. Nevertheless, few studies have discussed how a patriotic brand image is developed. The purpose of this study aims to fill the gap by examining whether and how a positive corporate image helps a domestic brand establish a patriotic brand image and in turn enhances consumers' purchase intentions in relation to domestic brand products.

A research model identifying the antecedents of patriotic brand image (the components of corporate image) is proposed and empirically tested using structural equations with a questionnaire investigating Taiwanese college students' attitudes toward Taiwanese smartphone brands. Three competing models are also proposed and tested to confirm the appropriateness of the research model.

In addition to the widely recognized impact of perceived quality on purchase intentions, patriotic brand image is found to be effective in enhancing local consumers' intentions to purchase domestic brand products. To shape a patriotic brand image, perceived quality, perceived corporate ability and perceived corporate integrity are the direct approaches, while perceived corporate social responsibility works through perceived corporate integrity, and perceived employer brand enhances only perceived corporate social responsibility.

Potential sampling (college students) and subject (smartphones) biases may limit the generalizability of the presented findings

While patriotic appeals have long been used in marketing communication, they are also likely to precipitate negative brand associations (e.g. nationalism), offending consumers in other countries. By contrast, the development of a positive corporate image serves as an implicit and neutral approach to building a patriotic brand image and can help domestic brands attract local consumers with less harm to foreign markets.

This study is one of notably few studies discussing patriotic brand image and its impacts on purchase intentions. This study also identifies the antecedents of patriotic brand image and how each of them affects patriotic brand image. The findings can help guide domestic brands in building a patriotic brand image.

The authors investigated a psychological process that links characteristics of events related to the coronavirus disease (2019) COVID-19 pandemic (i.e. perceived novelty, disruptiveness and criticality) to compassion fatigue [(CF), a form of caregiver burnout] and subsequent post-traumatic stress disorder (PTSD) in nurses.

Administering two online surveys (October and November 2020) resulted in matched data from 175 nurses responsible for patient care during the COVID-19 pandemic.

Perceived disruptiveness and criticality of COVID-19 events were positively associated with nurses' CF, which also mediated those characteristics' effects on PTSD instigated by COVID-19. Contrary to the authors' hypothesis, the perceived novelty of COVID-19 events was not significantly associated with CF nor was the indirect effect of perceived novelty on PTSD mediated by CF.

The authors extend event system theory by investigating the psychological processes linking event features and resultant outcomes while providing practical implications on preparations for future unexpected and potentially life-altering events.

The authors explain the conditions under which positive personality traits and work environment factors either interact synergistically or yield diminishing-gains when creative individuals are in a supportive working environment.

Data were obtained using a time-lagged design. The final sample includes 350 researchers from 64 scientific research teams.

The results indicate that the need for cognition is positively associated with individual creativity. Furthermore, this study suggests that perceived organizational support for creativity can complement an individual's need for cognition when it comes to individual creativity. This indicates a synergistic pattern. On the other hand, psychological safety can substitute for an individual's need for cognition when influencing individual creativity. Thus, a diminishing-gains pattern also exists.

The results suggest that when individuals are stuck in environments of low psychological safety, yet perceive higher levels of organizational support for creativity, their levels of creativity can be boosted.

This study is among one of the first to explore a supportive context's complementary or substitution effect on positive personality traits by demonstrating the complementary effect of perceived organizational support for creativity and the substitution effect of psychological safety. This study validates the positive effect of the need for cognition on creativity. This study also enriches the psychological safety literature by showing that psychological safety is not always necessary for individuals with a high need for cognition.

China after 1949, especially since entering the 21st century, significant progress has been made in leadership research under Chinese context. However, so far there has been no systematic review and prospect of China's leadership research in the past 70 years. Therefore, with the help of scientific visualization software Citespace, this paper analyzes the research papers on leadership in the context of China from the top international journals of management science and applied psychology (1949–2018), supplemented and verified the previous research conclusions based on qualitative review, and quantitatively demonstrated the research evolution of leadership field.

Using a scientific visualization tool CiteSpace and 145 international leadership works, which were published in 64 top international journals and collected from the Web of Science database, and 852 domestic works which were published in 28 top domestic journals and collected from the CNKI database from 1949 to 2018, we draws keyword co-occurrence knowledge graph and keyword strategy map to visualize the landscape and evolution of leadership research and analyze the hot topics and research trends in the field of leadership.

The research found that: (1) Before 2002, there were only 7 articles published in 64 international top journal, mainly focusing on Western leadership theories such as transformational, cross-cultural comparison and the adaptability in Chinese context; (2) From 2003 to 2012, scholars had begun to introduce mainstream quantitative research paradigm in international academic community; (3) From 2013 to 2018, researches tended to be synchronized, with 461 and 99 papers published respectively. How emerging leaderships (such as ethical leadership) affect on various emerging outcome variables (such as creativity, voice behavior, unethical pro-organizational behavior etc.) is hot topic for future research.

Different from the previous qualitative reviews on organizational culture research, this paper, for the first time, uses bibliometric research methods to systematically analyze the evolution path of leadership research during the 70 years of China(1949–2018, and puts forward the future research prospects.

This paper aims to solve the disadvantages of content-based domain ontology (CBDO) and metadata-based domain ontology (MDO) and improve organization and discovery efficiency of library resources by resource ontology (RO).

The paper constructed an RO model. Methods of informetrics are utilized to reveal semantic relationships among library resources. Methods of ontology, ontology-relational database mapping (O-R mapping) and relational database modelling are utilized to construct RO. Take author co-occurrence for example, the paper demonstrated the capability of RO model.

RO not only revealed the deep-level semantic relationships of metadata of library resources but also realized totally computer-automated processing. RO improved the efficiency of knowledge organization and discovery.

Semantic relationships revealed by RO are limited to simple metadata, which makes it difficult to reveal fine-grained semantic relationships. Ongoing research focuses on the revelation of semantic relationships based on the title and abstract.

The paper includes implications for utilizing methods of Informetrics to construct ontology.

This paper proposed a standardized process of ontology construction in library resources. It may be of potential interest for anyone who needs to effectively organize library resources.