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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.

Drawing on cognitive appraisal theory, this study aims to explore the indirect effect of work/family boundary violations on teleworkers’ counterproductive work behavior (CWB). In addition, it examines the moderating role of involuntary teleworking in this context.

Based on the diary study method, this study used 543 questionnaires collected from 122 teleworkers in China.

The findings indicate that working time demands mediate the relationship between work boundary violations and teleworker CWB, and threats to family roles mediate the relationship between family boundary violations and teleworker CWB. In addition, involuntary teleworking positively moderates the relationship between work boundary violations and working time demands, as well as the relationship between family boundary violations and threats to family roles.

The study makes several valuable contributions to the extant literature. First, it enhances research on the antecedents of teleworker CWB. Second, by introducing two mediating variables corresponding to two types of boundary violations, the paper provides new insights and a fresh understanding of the effects of boundary violations in teleworking situations. Third, by considering the moderating role of involuntary teleworking, this research adds to the current knowledge on the impact of discussing boundary violations solely on teleworking or traditional office days.

Wire-arc-based additive manufacturing (WAAM) is a promising technology for the efficient and economical fabrication of medium-large components. However, the anisotropic behavior of the multilayered WAAM-fabricated components remains a challenging problem.

The purpose of this paper is to conduct a comprehensive study of the grain morphology, crystallographic orientation and texture in three regions of the WAAM printed component. Furthermore, the interdependence of the grain morphology in different regions of the fabricated component with their mechanical and tribological properties was established.

The electron back-scattered diffraction analysis of the top and bottom regions revealed fine recrystallized grains, whereas the middle regions acquired columnar grains with an average size of approximately 8.980 µm. The analysis revealed a higher misorientation angle and an intense crystallographic texture in the upper and lower regions. The investigations found a higher microhardness value of 168.93 ± 1.71 HV with superior wear resistance in the bottom region. The quantitative evaluation of the residual stress detected higher compressive stress in the upper regions. Evidence for comparable ultimate tensile strength and greater elongation (%) compared to its wrought counterpart has been observed.

The study found a good correlation between the grain morphology in different regions of the WAAM-fabricated component and their mechanical and wear properties. The Hall–Petch relationship also established good agreement between the grain morphology and tensile test results. Improved ductility compared to its wrought counterpart was observed. The anisotropy exists with improved mechanical properties along the longitudinal direction. Moreover, cylindrical components have superior tribological properties compared with cuboidal components.

The study examines tourists' psychological and social risk and shared beliefs – devotion, concerns and entertainment – at a religious and cultural heritage destination. It also examines how shared beliefs impact tourists’ nostalgia. Further, it examines whether nostalgia affects choice deferral and revisit intentions. Finally, it investigates how moderation of place attachment strengthens the link between shared beliefs – devotion, concerns, entertainment and nostalgia.

The data were collected from 439 inbound tourists, with 272 completing online questionnaires and 167 participating in face-to-face survey. Data analysis was performed using Amos 24.0 and SPSS 25.0, employing structural equation modeling (SEM) and the PROCESS macro.

The findings suggest that perceived psychological and social risk negatively impacts tourists' shared beliefs – devotion, concerns and entertainment – which positively impacts nostalgia. Positive nostalgic association boosts revisit intention and hampers choice deferral. The data also show how strong place attachment strengthens the relationship between shared beliefs – devotion, concerns and entertainment – and tourists’ perceived nostalgia.

This work contributes to information behavior using S-O-R theory. It analyzes the psychological and social risks of destination visits and how nostalgia affects shared beliefs and revisit intentions. Management and policymakers at destination enterprises can use the findings to design measures to enhance revisit intentions despite risk considerations.

Pakistan's destination tourism is underutilized amid its religious and cultural heritage significance. The literature has ignored how perceived psychological and social risk affects travelers' shared beliefs and nostalgic feelings. Thus, this study suggests and validates these linkages utilizing stimulus-organism-response (S-O-R) theory in Pakistan's unique environment with inbound tourists.

This paper aims to describe a proposal for an innovative method of normal shock wave–turbulent boundary layer interaction (SBLI) and shock-induced separation control.

The concept is based on the introduction of a tangentially moving wall upstream of the shock wave and in the interaction region. The SBLI control mechanism may be implemented as a closed belt floating on an air cushion, sliding over two cylinders and forming the outer skin of the suction side of the airfoil. The presented exploratory numerical study is conducted with SPARC solver (steady 2D RANS). The effect of the moving wall is presented for the NACA 0012 airfoil operating in transonic conditions.

To assess the accuracy of obtained solutions, validation of the computational model is demonstrated against the experimental data of Harris, Ladson & Hill and Mineck & Hartwich (NASA Langley). The comparison is conducted not only for the reference (impermeable) but also for the perforated (permeable) surface NACA 0012 airfoils. Subsequent numerical analysis of SBLI control by moving wall confirms that for the selected velocity ratios, the method is able to improve the shock-upstream boundary layer and counteract flow separation, significantly increasing the airfoil aerodynamic performance.

The moving wall concept as a means of normal shock wave–turbulent boundary layer interaction and shock-induced separation control has been investigated in detail for the first time. The study quantified the necessary operational requirements of such a system and practicable aerodynamic efficiency gains and simultaneously revealed the considerable potential of this promising idea, stimulating a new direction for future investigations regarding SBLI control.

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.

This study is based on the heuristic-systematic model (HSM) to dynamically examine the effect of review variance on sales and the boundary conditions that mitigate this effect.

Based on the theoretical domain of HSM, a conceptual model is proposed that analyzes the nonlinear relationship between review variance and sales and the interaction and motivation factors that moderate these relationships. Review data from websites targeting the film industry in the USA and South Korea (Korea) were collected to empirically analyze the authors' hypothesis, and panel regression analysis was used for confirmation.

Moderated by interactive and motivational factors, review variance exhibits an inverse-U-shaped relationship with review variance. Specifically, as an interaction factor, review valence and owned social media (OSM) resulted in positive interaction effects, and as a motivation factor, the number of alternatives exhibited a positive interaction effect with review variance. The effect of review variance was less pronounced in the USA than in Korea.

The study outcomes reveal a nonlinear relationship between review variance and sales, thus supporting the contradictory findings of previous studies. This study contributes to the literature by using the HSM as a theoretical framework to verify various HSM mechanisms using online review data. This exploratory study also contributes to the international marketing literature by showing that the effects of review variance vary across cultures.

This study aims to investigate whether higher value creation leads to higher value appropriation and to identify the boundary conditions in a buyer–supplier relationship that can explain why a particular supplier can appropriate higher value than others.

The study uses questionnaire surveys. The sample of the survey has 150 publicly-listed supplier firms in Taiwan. The unit of analysis is the buyer–supplier relationship.

In the buyer–supplier relationship, suppliers’ bargaining power, partnership and a supplier’s original brand manufacturing (OBM) business can strengthen the positive relationship between value creation and value appropriation.

This study adopts the unilateral viewpoint of suppliers; however, some constructs might require dyadic evaluation. This study only explores the spillover effect of OBM business on the relationship between value creation and appropriation.

The spillover effect of a supplier’s OBM business in a buyer–supplier relationship allows the buyer to share more common benefits and the supplier to capture more private benefits as compensation. By broadening its customer base, a supplier can increase its bargaining power. A supplier can also maintain a strategic partnership with each essential buyer.

To avoid the dark-side effect of partnership, the model provides the contingency that a supplier can capture more value from a buyer–supplier relationship.

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.

The purpose of this study is to explore the relationship between nonmarket strategy and innovation performance, as well as the boundary factors that influence this relationship in the context of the pharmaceutical industry in emerging markets.

This study analyzed matched data of 227 Chinese pharmaceutical firms and two secondary databases with SPSS to examine the hypotheses.

Nonmarket strategy promotes the innovation performance. High level of firm internal knowledge utilization ability and strategic flexibility strengthens the effect of nonmarket strategy in promoting innovation performance, while information technology (IT) environment weakens the effect of nonmarket strategy in promoting innovation performance.

The research studies the positive impact of nonmarket strategy on innovation performance in the specific context of Chinese pharmaceutical industry, and it introduces the internal capabilities and external IT environment of the firm as moderators of the relationship between nonmarket strategy and innovation performance. More importantly, this research echoes the call for research on moderator of nonmarket strategy and identifies important boundary conditions. To the best of the authors’ knowledge, it also explores the impact of the IT environment on the implementation of nonmarket strategy for the first time, which deepens the research on nonmarket strategy’s effect on innovation.