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This study aims to investigate the rarefaction effects on flow and thermal performances of an equivalent sand-grain roughness model for aerodynamic thrust bearing.

In this study, a model of gas lubrication thrust bearing was established by modifying the wall roughness and considering rarefaction effect. The flow and lubrication characteristics of gas film were discussed based on the equivalent sand roughness model and rarefaction effect.

The boundary slip and the surface roughness effect lead to a decrease in gas film pressure and temperature, with a maximum decrease of 39.2% and 8.4%, respectively. The vortex effect present in the gas film is closely linked to the gas film’s pressure. Slip flow decreases the vortex effect, and an increase in roughness results in the development of slip flow. The increase of roughness leads to a decrease for the static and thermal characteristics.

This work uses the rarefaction effect and the equivalent sand roughness model to investigate the lubrication characteristics of gas thrust bearing. The results help to guide the selection of the surface roughness of rotor and bearing, so as to fully control the rarefaction effect and make use of it.

The purpose of this paper is to analyze numerically the blowup in finite time of the solutions to a one-dimensional, bidirectional, nonlinear wave model equation for the propagation of small-amplitude waves in shallow water, as a function of the relaxation time, linear and nonlinear drift, power of the nonlinear advection flux, viscosity coefficient, viscous attenuation, and amplitude, smoothness and width of three types of initial conditions.

An implicit, first-order accurate in time, finite difference method valid for semipositive relaxation times has been used to solve the equation in a truncated domain for three different initial conditions, a first-order time derivative initially equal to zero and several constant wave speeds.

The numerical experiments show a very rapid transient from the initial conditions to the formation of a leading propagating wave, whose duration depends strongly on the shape, amplitude and width of the initial data as well as on the coefficients of the bidirectional equation. The blowup times for the triangular conditions have been found to be larger than those for the Gaussian ones, and the latter are larger than those for rectangular conditions, thus indicating that the blowup time decreases as the smoothness of the initial conditions decreases. The blowup time has also been found to decrease as the relaxation time, degree of nonlinearity, linear drift coefficient and amplitude of the initial conditions are increased, and as the width of the initial condition is decreased, but it increases as the viscosity coefficient is increased. No blowup has been observed for relaxation times smaller than one-hundredth, viscosity coefficients larger than ten-thousandths, quadratic and cubic nonlinearities, and initial Gaussian, triangular and rectangular conditions of unity amplitude.

The blowup of a one-dimensional, bidirectional equation that is a model for the propagation of waves in shallow water, longitudinal displacement in homogeneous viscoelastic bars, nerve conduction, nonlinear acoustics and heat transfer in very small devices and/or at very high transfer rates has been determined numerically as a function of the linear and nonlinear drift coefficients, power of the nonlinear drift, viscosity coefficient, viscous attenuation, and amplitude, smoothness and width of the initial conditions for nonzero relaxation times.

The purpose of this study is to test the mechanism of visionary leadership on subordinates' work withdrawal behavior through cognitive strain and psychological contract violation, and also to reveal the possible dark side of visionary leadership. The moderation effects of subordinates' facades of conformity and leader behavioral integrity in the cognition–affect dual-path process are also discussed.

This study conducted a three-wave longitudinal survey. The data were collected from 574 employees and their superiors in several Chinese enterprises. The authors used Mplus 7.4 and adopted a bootstrapping technique in the data analysis.

Visionary leadership has positive effects on cognitive strain and psychological contract violation; cognitive strain and psychological contract violation mediate the relationship between visionary leadership and work withdrawal behavior, respectively. Subordinates' facades of conformity and leader behavioral integrity moderate the positive effects of visionary leadership on cognitive strain and psychological contract violation, as well as the indirect effect of visionary leadership on subordinates' work withdrawal behavior through cognitive strain and psychological contract violation.

This study reveals the underlying mechanism of visionary leadership's negative impact on job outcome through the cognition and affective reaction of subordinates to visionary leadership, and broadens the scope of visionary leadership research. It also provides some practical suggestions on how to transmit the organizational vision effectively and reduce subordinates' work withdrawal behavior.

This paper examined the mediating role of boundary spanning behavior and the moderating effects of traditionality linking humble leadership and employee creative performance from the perspective of Social Exchange Theory (SET) to reveal the behavioral mechanism and boundary condition regarding the influence of humble leadership on creative performance.

A sample of 276 employees and the supervisors from 8 companies in China was taken using two-wave data.

The results indicated that humble leadership was positively related to employee creative performance, and boundary spanning behavior partially mediated the relationship between humble leadership and employee creative performance. Traditionality strengthens the mediation process when traditionality is high.

These findings provide several theoretical and practical implications for the domains of humble leadership and boundary spanning behavior. For example, human resource (HR) departments can recruit leaders with high humility and cultivate team leaders through systematic training programs about self-awareness, openness and self-transcendence; team leaders should encourage employees to participate in boundary spanning activities and hiring managers select employees with high traditionality to synergize with leader humility.

Based on the SET, this paper explored the behavioral mechanism between humble leadership and creative performance and enriched the prior research, which is from the cognitive or emotional view, and further answered the question “what are the employees' behavioral responses when they confront the humble leadership”.

Considering Gen Z’s unique formative experience with social media, this study aims to apply the cue utilization theory to investigate the effects of social media policy as an organizational cue in attracting this cohort to hospitality and tourism (H&T) companies.

A 2 (policy frame: promotion/prevention) × 2 (policy boundary: distinct/permeable) experiment was conducted with 243 Gen Z H&T job seekers. ANCOVA analyses were performed to analyze the effects of policy frame and boundary on perceived organization attractiveness and pursuit intention, respectively.

This study found that when a company policy promoted social media usage, Gen Z job seekers reported higher attractiveness and pursuit intention in the distinct boundary condition. However, when a company’s social media policy emphasized a prevention frame, Gen Z job seekers reported a similar level of perceived attractiveness and pursuit intention, regardless of the policy boundary conditions.

This study addressed the literature gaps of limited research on the Gen Z workforce and the effects of social media policy on talent attraction. Based on the cue utilization theory, this study identified the policy clause combinations that generated positive recruitment impacts among Gen Z members. The study provided unique theoretical and practical implications for H&T managers to use social media policy as a novel and cost-effective tool to attract Gen Z talents.

考虑到 Z 世代在社交媒体方面的独特成长经历, 本研究借鉴了线索利用理论, 调查了社交媒体公司政策作为组织线索在吸引这一年轻人才群体加入酒店和旅游公司方面的影响。

本研究在 243 名 Z 世代潜在的酒店和旅游从业人员中进行了 2（政策框架：促进与预防）x 2（政策边界：明显与模糊）的实验。 通过一系列 2x2 ANCOVA 分析来确认政策框架和政策边界对Z 世代的劳动力在组织吸引力和求职意愿的影响。

研究结果表明, 当公司提倡在工作中使用社交媒体, Z世代潜在员工觉得有明显边界政策的公司 （相对于有模糊边界政策的公司）具有更高的吸引力和追求意愿。 然而, 当公司的社交媒体政策强调预防框架时, 无论政策边界如何界定, Z 世代潜在员工都表示相似的组织吸引力和求职意愿。

本研究从人才吸引的角度来填补了关于 Z 世代劳动力和社交媒体政策的研究空白。 基于线索利用理论, 该研究揭示了对 Z 世代成员产生积极招聘影响的政策条款组合。 该研究为酒店和旅游管理人员使用社交媒体政策作为吸引 Z 世代人才的新颖且具有成本效益的工具提供了独特的理论和实践意义。

Teniendo en cuenta la experiencia formativa única de la Generación Z con los medios sociales, este estudio aplica la teoría de la utilización de señales para investigar los efectos de la política de medios sociales como indicio organizativo para atraer a esta cohorte a las empresas de hostelería y turismo.

Se realizó un experimento de 2x2 (marco de la política: promoción vs prevención) x (límite de la política: distinto vs permeable) con 243 personas de la Generación Z en busca de empleo en hostelería y turismo. Se aplicaron análisis ANCOVA para analizar los efectos del marco de política y el límite en el atractivo percibido de la organización y la intención de búsqueda, respectivamente.

Este estudio descubrió que cuando la política de una empresa promovía el uso de los medios sociales, los solicitantes de empleo de la Generación Z declaraban un mayor atractivo y una mayor intención de búsqueda en la condición de límite diferenciado. Sin embargo, cuando la política de medios sociales de una empresa hacía hincapié en un marco de prevención, los solicitantes de empleo de la Generación Z informaron de un nivel similar de atractivo percibido e intención de búsqueda, independientemente de las condiciones de límite de la política.

Este estudio abordó las lagunas en la literatura debido a la investigación limitada sobre la fuerza laboral de la Generación Z y los efectos de las políticas de redes sociales en la atracción de talento. Basado en la teoría de utilización de señales, el estudio identificó las combinaciones de cláusulas de política que generaron impactos positivos en la contratación entre miembros de la Generación Z. El estudio proporcionó implicaciones teóricas y prácticas únicas para que los gerentes de hostelería y turismo utilicen las políticas de redes sociales como una herramienta novedosa y rentable para atraer talento de la Generación Z.

This study aims to investigate the negative interpersonal antecedents, emotional mediators and boundary conditions of knowledge sabotage behavior.

The authors collected data from 275 Chinese employees using convenience sampling and snowball sampling across three stages. Subsequently, the authors used both hierarchical regression and bootstrap methods to test the proposed hypotheses.

The results confirmed that workplace ostracism has positive effects on employee knowledge sabotage behavior both directly and via employee anger. In addition, the authors found that employee bottom-line mentality (BLM) moderates not only the direct effect of workplace ostracism on employee anger but also the indirect effect of employee anger in this context. Employee conscientiousness moderates only the direct effect of workplace ostracism on employee anger and does not moderate the indirect effect.

To the best of the authors’ knowledge, this study not only explores the influence of workplace ostracism on employee knowledge sabotage behavior for the first time but also elucidates the underlying emotional mechanisms (anger) and boundary conditions (employee BLM and conscientiousness) by which workplace ostracism influences employee knowledge sabotage behavior, thus deepening the understanding of how knowledge sabotage emerges in organizations.

The advancement of enterprise social networks (ESNs) facilitates information sharing but also presents the challenge of managing information boundaries. This study aims to explore the factors that influence the information-control behavior of ESN users when continuously sharing information.

This study specifies the information-control behaviors in the “wall posts” channel and applies communication privacy management (CPM) theory to analyze the effects of the individual-specific factor (disposition to value information), context-specific factors (work-relatedness and information richness) and risk-benefit ratio (public benefit and public risk). Data on actual information-control behaviors extracted from ESN logs are examined using multilevel mixed-effects logistic regression analysis.

The study's findings show the direct effects of the individual-specific factor, context-specific factors and risk-benefit ratio, highlighting interactions between the individual motivation factor and ESN context factors.

This study reshapes the relationship of CPM theory boundary rules in the ESN context, extending information-control research and providing insights into ESNs' information-control practices.

The purpose of this study is to propose a precise and standardized strategy for numerically simulating vehicle aerodynamics.

Error sources in computational fluid dynamics were analyzed. Additionally, controllable experiential and discretization errors, which significantly influence the calculated results, are expounded upon. Considering the airflow mechanism around a vehicle, the computational efficiency and accuracy of each solution strategy were compared and analyzed through numerous computational cases. Finally, the most suitable numerical strategy, including the turbulence model, simplified vehicle model, calculation domain, boundary conditions, grids and discretization scheme, was identified. Two simplified vehicle models were introduced, and relevant wind tunnel tests were performed to validate the selected strategy.

Errors in vehicle computational aerodynamics mainly stem from the unreasonable simplification of the vehicle model, calculation domain, definite solution conditions, grid strategy and discretization schemes. Using the proposed standardized numerical strategy, the simulated steady and transient aerodynamic characteristics agreed well with the experimental results.

Building upon the modified Low-Reynolds Number k-e model and Scale Adaptive Simulation model, to the best of the authors’ knowledge, a precise and standardized numerical simulation strategy for vehicle aerodynamics is proposed for the first time, which can be integrated into vehicle research and design.

This paper aims at studying numerically the entropy generation of nanofluid flowing over an inclined sheet in the presence of external magnetic field, heat source/sink, chemical reaction along with slip boundary conditions imposed on an impermeable wall.

A suitable similarity transformation technique has been used to convert the coupled nonlinear partial differential equations to ordinary differential equations (ODEs). The ODEs are then solved simultaneously using the finite difference method implemented through an in-house computer program. The effects of different controlling parameters such as magnetic parameter, radiation parameter, Brownian motion parameter, thermophoresis parameter, chemical reaction parameter, Reynolds number, Brinkmann number, Prandtl number, velocity slip parameter, temperature slip parameter and the concentration slip parameter on the entropy generation and Bejan number have been discussed comprehensively through the relevant physical insights for the first time.

The relative strengths of the irreversibilities due to heat transfer, fluid friction and the mass diffusion arising due to the change in each of the controlling variables have been delineated both in the near-wall and far-away-wall regions, which may be helpful for a better understanding of the thermo-fluid dynamics of nanofluid in boundary layer flows. The numerical results obtained from the present study have also been validated with results published in open literature.

The effects of different controlling parameters such as magnetic parameter, radiation parameter, Brownian motion parameter, thermophoresis parameter, chemical reaction parameter, Reynolds number, Brinkmann number, Prandtl number, velocity slip parameter, temperature slip parameter and the concentration slip parameter on the entropy generation and Bejan number have been discussed comprehensively through the relevant physical insights for the first time.

This study aims to analyze the two-dimensional ferrofluid flow in porous media. The effects of changes in parameters such as permeability parameter, buoyancy parameter, Reynolds and Prandtl numbers, radiation parameter, velocity slip parameter, energy dissipation parameter and viscosity parameter on the velocity and temperature profile are displayed numerically and graphically.

By using simplification, nonlinear differential equations are converted into ordinary nonlinear equations. Modeling is done in the Cartesian coordinate system. The finite element method (FEM) and the Akbari-Ganji method (AGM) are used to solve the present problem. The finite element model determines each parameter’s effect on the fluid’s velocity and temperature.

The results show that if the viscosity parameter increases, the temperature of the fluid increases, but the velocity of the fluid decreases. As can be seen in the figures, by increasing the permeability parameter, a reduction in velocity and an enhancement in fluid temperature are observed. When the Reynolds number increases, an increase in fluid velocity and temperature is observed. If the speed slip parameter increases, the speed decreases, and as the energy dissipation parameter increases, the temperature also increases.

When considering factors like thermal conductivity and variable viscosity in this context, they can significantly impact velocity slippage conditions. The primary objective of the present study is to assess the influence of thermal conductivity parameters and variable viscosity within a porous medium on ferrofluid behavior. This particular flow configuration is chosen due to the essential role of ferrofluids and their extensive use in engineering, industry and medicine.