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The CL60 steel wheels of metro vehicles running on a specific line need frequent reprofiling due to rapid wear. Considering this problem, a new material for metro wheels was designed. The friction and wear properties of the new material were studied, to reduce the wear rate and extend the service life of metro wheels.

Wheel specimens made of the two steel materials were tested using a GPM-60 wear tester under laboratory conditions. A field test was conducted on a specific metro line to track the wear in wheels made of the new material and CL60 steel wheels.

Under the laboratory conditions, the wear loss in the new material was 24.44% lower than that in CL60 steel. The field test revealed that compared to CL60 steel wheels, the new CL60 steel wheels showed a 19.42% decrease in tread wear on average. The field measurements for the wheels made of the new material are consistent with the results of laboratory simulation, suggesting relatively high wear resistance of the new material.

The results of the study can provide guidance on how to properly select steel material for metro wheels to avoid rapid wear and frequent reprofiling and reduce operating costs.

A new material for metro wheels was designed and developed by optimizing the content of Cr, Si, Mn, V and other elements. This material proved to have better wear resistance in both laboratory and field testing.

The purpose of this paper is to study the wear evolution of metro wheels under the conditions of different track sequences, track composition and vehicle load and then to predict wheel wear and to guide its maintenance.

By using the SIMPACK and MATLAB software, numerical simulation analysis of metro wheel wear is carried out based on Hertz theory, the FASTSIM algorithm and the Archard model. First of all, the vehicle dynamics model is established to calculate the motion relationship and external forces of wheel-rail in the SIMPACK software. Then, the normal force of wheel-rail is solved based on Hertz theory, and the tangential force of wheel-rail is calculated based on the FASTSIM algorithm through the MATLAB software. Next, in the MATLAB software, the wheel wear is calculated based on the Archard model, and a new wheel profile is obtained. Finally, the new wheel profile is re-input into the vehicle system dynamics model in the SIMPACK software to carry out cyclic calculation of wear.

The results show that the setting order of different curves has an obvious influence on wear when the proportion of the straight track and the curve is fixed. With the increase in running mileage, the severe wear zone is shifted from tread to flange root under the condition of the sequence-type track, but the wheel wear distribution is basically stable for the unit-type track, and their wear growth rates become closer. In the tracks with different straight-curved ratio, the more proportion the curved tracks occupy, the closer the severe wear zone is shifted to flange root. At the same time, an increase in weight of the vehicle load will aggravate the wheel wear, but it will not change the distribution of wheel wear. Compared with the measured data of one city B type metro in China, the numerical simulation results of wheel wear are nearly the same with the measured data.

These results will be helpful for metro tracks planning and can predict the trend of wheel wear, which has significant importance for the vehicle to do the repair operation. At the same time, the security risks of the vehicle are decreased economically and effectively.

At present, many scholars have studied the influence of metro tracks on wheel wear, but mainly focused on a straight line or a certain radius curve and neglected the influence of track sequence and track composition. This study is the first to examine the influence of track sequence on metro wheel wear by comparing the sequence-type track and unit-type track. The results show that the track sequence has a great influence on the wear distribution. At the same time, the influence of track composition on wheel wear is studied by comparing different straight-curve ratio tracks; therefore, wheel wear can be predicted integrally under different track conditions.

Employee’s service innovative behavior lays the groundwork for bottom-up innovation and ongoing service improvement in service firms. Therefore, it is vital for service organizations to understand the antecedents of employees service innovative behavior. Drawing upon the social cognitive theory, this study aims to develop a research model that examines the effects of ethical and entrepreneurial leadership on service innovative behavior.

Data were collected from 178 managers and 415 employees working in 178 small- and medium-sized (SME) hotels in Vietnam.

The findings showed that ethical leadership has direct and indirect effects on service innovative behavior, while entrepreneurial leadership only influences service innovative behavior via intrinsic motivation. In addition, trust in leader moderates the effect of intrinsic motivation on service innovative behavior

The study advances current scholarly research on leadership by combining the two areas of entrepreneurial and ethical leadership into one theoretical model and examines how these leadership styles generate hospitality employees’ service innovative behavior through the mediating effect of intrinsic motivation and the moderating effect of trust in leader.

The findings of this research offer significant implications for SME hotels and their managers. In their recruitment processes, hotels should search for particular personality traits, which have been found to predict ethical and entrepreneurial leadership. Hospitality firms also need to encourage communication between leaders and co-workers to enhance employees’ intrinsic motivation.

There are calls for research to examine whether both entrepreneurial and ethical leadership styles can be integrated to enhance employees’ positive outcomes. Evidence about the mechanism linking entrepreneurial and ethical leadership to service innovative behavior is limited. With this stated, the current study makes significant contribution to leadership and innovation literature by filling in these voids.

The purpose of this paper is to investigate the relationship between servant leadership and life satisfaction through the mediating role of workplace positive affect (WPA), and the moderating roles of collectivistic orientation and general self-efficacy.

Using a sample of 304 employees in a two-wave survey, the hypotheses were demonstrated with hierarchical regression analyses.

The results revealed that servant leadership was positively related to employee life satisfaction, and WPA served as a mediator between them. Moreover, collectivistic orientation and general self-efficacy moderated the relationship between servant leadership and WPA, and the indirect effect of servant leadership on life satisfaction via WPA.

The time-lagged research design of this study may limit the ability to draw causal conclusions. Moreover, as this research was conducted in a Chinese context, the question of the generalizability of our findings calls for more attention.

Leaders are encouraged to adopt the servant leadership style to facilitate employee life satisfaction and organizations should select and recruit managers with servant leadership qualities. Furthermore, because employees’ collectivistic orientation and general self-efficacy moderate the effects of servant leadership on followers’ outcomes, managers need to take individual differences into consideration when they implement managerial strategy.

This research contributed to a burgeoning stream of servant leadership literature by investigating the functions of servant leadership in promoting life satisfaction, and exploring the affective mechanism linking servant leadership and life satisfaction as well as the boundary conditions of collectivistic orientation and general self-efficacy.

The purpose of this paper is to demonstrate the I‐V characteristics of ZnO film on Si substrates with Ag buffer layer by conductive atomic force (C‐AFM).

An Ag buffer layer and Zn film was first deposited on silicon substrate by RF‐sputtering deposition method from high pure Ag and Zn target, respectively. Then, the deposited film was sintered in air at 500°C for 1 h.

The structures and morphologies of the prepared films were characterized by X‐ray diffraction (XRD), energy dispersive spectrum (EDS), atomic force microscopy (AFM), and C‐AFM. The results show that the prepared ZnO films with Ag buffer layer have a good crystallinity and surface morphology. Interestingly, the I‐V curve of ZnO film exhibited typical characteristics of semi‐conductive oxide under the conductive Ag buffer layer.

The paper demonstrates, by C‐AFM, that the ZnO/Ag‐buffer/Si exhibits excellent crystal structure, morphology and typical I‐V characteristics.

The main purpose of this study is to investigate the mechanism through voice behavior mediates the relationship between ethical leadership and employees' creativity. This study also examines the moderating role of psychological empowerment and innovative climate between ethical leadership and employee creativity.

We used a survey questionnaire to collect multi-wave data from 295 employees working in the IT sector to test the proposed hypotheses of this study.

The findings revealed that ethical leadership boosts employee creativity, and voice behavior mediates the positive relationship between ethical leadership and employee creativity. Moreover, the results confirm the significant moderating role of psychological empowerment on the relationship between ethical leadership and voice behavior. A positive moderation of innovative climate was also confirmed in the association between voice behavior and creativity. Employees with supportive innovative climate adopt creative behavior when they can voice their concerns freely.

Ethical leadership is a vital tool for fostering employee's creativity by providing autonomy to raise their voice at the workplace in the emerging markets.

This is one of the leading researches to emphasize the role of ethical leadership for employee creativity, and the key contribution is to discover voice as a potential mediator for ethical leadership and an innovative climate as a potential moderator in the relationship between voice behavior and employee creativity.

In hypercompetitive markets, retail brands should fuel their sales employees’ to responsively serve customers. In connection, the study aims to unpack the direct and indirect, via psychological flourishing, the role of inclusive leadership in paving the path for retail salesperson adaptive selling behaviour. Additionally, the study also empirically investigates the moderating role of work centrality to offer critical insights for effective managerial interventions.

Drawing upon conservation of resource theory to test the nexuses of the model, time-lagged survey data were collected from 313 retail salespersons from the leading retail brands. Data were analyzed using the bootstrapping method.

Results revealed the direct positive association between inclusive leadership and adaptive selling behaviour and indirect association via psychological flourishing. Furthermore, the direct association between inclusive leadership and adaptive selling becomes more pronounced for employees high on work centrality.

Findings can help retail brands to enhance adaptive selling behaviour, which enables them to provide efficient solutions and gain sustainable competitive advantage.

The study offers several important contributions to the sales literature by establishing the direct and indirect link between inclusive leadership and adaptive selling via psychological flourishing. Moreover, the result of the interaction effect highlights the critical aspects of work centrality in the retail sales context.

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.

The purpose of this study is to investigate the effects of nanoadditive lubricants on the vibration and noise characteristics of helical gears compared with conventional lubricants. The experiment aims to analyze whether nanoadditive lubricants can effectively reduce gear vibration and noise under different speeds and loads. It also analyzes the sensitivity of the vibration reduction to load and speed changes. In addition, it compares the axial and radial vibration reduction effects. The goal is to explore the application of nanolubricants for vibration damping and noise reduction in gear transmissions. The results provide a basis for further research on nanolubricant effects under high-speed conditions.

Helical gears of 20CrMnTi were lubricated with conventional oil and nanoadditive oils. An open helical gearbox with spray lubrication was tested under different speeds (200–500 rpm) and loads (20–100 N·m). Gear noise was measured by a sound level meter. Axial and radial vibrations were detected using an M+P VibRunner system and fast Fourier transform analysis. Vibration spectrums under conventional and nanolubrication were compared. Gear tooth surfaces were observed after testing. The experiment aimed to analyze the noise and vibration reduction effects of nanoadditive lubricants on helical gears and the sensitivity to load and speed.

The key findings are that nanoadditive lubricants significantly reduce the axial and radial vibrations of helical gears under low-speed conditions compared with conventional lubricants, with a more pronounced effect on axial vibrations. The vibration reduction is more sensitive to rotational speed than load. At the same load and speed, nanolubrication reduces noise by 2%–5% versus conventional lubrication. Nanoparticles change the friction from sliding to rolling and compensate for meshing errors, leading to smoother vibrations. The nanolubricants alter the gear tooth surfaces and optimize the microtopography. The results provide a basis for exploring nanolubricant effects under high speeds.

The originality and value of this work is the experimental analysis of the effects of nanoadditive lubricants on the vibration and noise characteristics of hard tooth surface helical gears, which has rarely been studied before. The comparative results under different speeds and loads provide new insights into the vibration damping capabilities of nanolubricants in gear transmissions. The findings reveal the higher sensitivity to rotational speed versus load and the differences in axial and radial vibration reduction. The exploration of nanolubricant effects on gear tribological performance and surface interactions provides a valuable reference for further research, especially under higher speed conditions closer to real applications.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2023-0220/

The purpose of the paper is to investigate the relationship between empowering leadership and the innovative work behavior of employees. Utilizing a moderated mediation mechanism, the study additionally uncovers the mediating impact of knowledge sharing and the moderating influence of role clarity in the proposed model.

Cross-sectional design was used in the study, and developed questionnaires were administered to 235 supervisor-subordinates dyads working in Indian organizations to test the proposed relationships. SPSS 20 and AMOS 20 were used for statistical analysis.

The hypothesized moderated mediation model was supported. Knowledge sharing mediated the relationship between empowering leadership and innovative work behavior. The moderating impact of role clarity between empowering leadership and knowledge sharing was supported. It was also observed that stronger role clarity strengthened the indirect relationship between empowering leadership and innovative work behavior. Overall, the study shows that empowering leaders creates a cultivating climate for innovative work behavior by encouraging knowledge sharing among the members subject to clear identification of employee roles.

Cross-sectional design of the study limits the authors from drawing definitive generalizations. Self-reported measures used in the study increase the chances of bias.

Findings of the study can be utilized by leaders for promoting innovative work behavior in the organization, which has been identified as a key to organizational growth and development.

The study attempts to address the under developed relationship between empowering leadership and innovative work behavior.