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The purpose of this study is to assess the effects of fused filament fabrication (FFF) printing parameters on the surface quality and dimensional accuracy of FFF-fabricated copper green parts using the appropriate filaments. The orthogonal experiments were implemented and the errors in length, width and height were measured and analyzed. The results of range analysis and variance analysis indicated the orders of effect factors. Dissolvent debinding combined with thermal debinding was adopted to remove the binders inside the green part by calculating debinding rate. The influence mechanism of sintering temperatures on the microstructure and shrinkage was elaborated.

The extrusion-based FFF in manufacturing copper parts can overcome shortcomings for high reflectivity and heat dissipation in laser powder bed fusion process at cost-saving and materials saving. This study makes an attempt to prepare copper/binder composite filaments through mixing, extrusion and flowability evaluation.

The results showed that the suitable composite filaments applied for FFF should balance rigidity and plasticity. The combination of printing speed and heating temperature impacts on the surface quality significantly, and the major factor in determining the dimensional accuracy is layer thickness. Two-stage debinding procedure was beneficial for binder removal and sintering process. The higher sintering temperature results in less voids, sizes shrinkage and densified microstructure, which is attributed to the occurrence of sintering neck among the fused copper powders.

The self-prepared copper/binder composite filaments were successfully manufactured using the FFF process. This study provides unique approach and print guidance for fabricating complex structures of pure copper components.

This study aims to explore the impact of printing parameters, specifically raster angle and layer thickness, on the microstructure and mechanical properties of green and sintered parts produced through filament-based fused filament fabrication (FFF) using a self-developed filament. The goal is to improve the quality and performance of the final sintered components.

A filament containing 92 Wt.% 316L stainless steel with polyoxymethylene (POM)-based binder was formulated and evaluated for flexibility through a buckling resistance test. Green parts were printed with varying raster angles (+45°/−45°, 0°/90°) and layer thicknesses (0.2 mm, 0.3 mm), followed by catalytic debinding and high-temperature sintering. Microstructure, dimensional accuracy and mechanical properties, including microhardness, tensile strength and elongation at break, were analyzed to identify optimal parameters.

A raster angle of (+45°/−45°) produced denser interlayer bonding and a more compact green part structure, whereas a thicker layer (0.3 mm) resulted in a looser structure with larger pores. The optimal combination of +45°/−45° raster angle and 0.2 mm layer thickness achieved the highest relative density (99.37%) and superior mechanical properties: microhardness (216.83 HV), tensile strength (467.59 MPa) and elongation at break (16.81%).

A 92 Wt.% 316L stainless-steel filament for FFF was independently developed and near dense steel components were successfully fabricated. This study provides new insight into developing a novel formula of filament and optimizing printing parameters for FFF technology.

Given the cruciality of construction workers' safe behaviors, the possible influential factors on workers' behaviors should be studied, and one of these factors is characteristics. The authors identified emotional intelligence (EI), motivation and job burnout as characteristics that might affect a worker's safety behavior, and the aim of this study is to investigate these possible relationships.

Workers' EI, motivation and job burnout status were assessed by a structured interview. Furthermore, workers' safety behaviors were assessed by a checklist derived from national codes, regulations and other research studies. Then, the researcher's observations took place, and the data were acquired.

EI and motivation of workers were able to predict safety behaviors, and the effect of job burnout on safety behaviors was not significant. In addition, motivation's influence on job burnout was not significant. Therefore, in order to promote safety behaviors, the EI and motivation of workers need to be taken into consideration.

The results indicate why construction managers should consider the workers' EI and motivation competencies and how this consideration could lead to safer and better performance in construction projects.

The possible effects of EI, motivation and job burnout on the safety behaviors of construction workers haven't been paid enough attention. Moreover, the authors couldn't find a study similar to the present one that was conducted in Iran. Also, an original model was presented, and safety behaviors were studied through fieldwork rather than using questionnaires.

Aero-engine casings commonly use composite cylindrical shell structures with excellent properties such as corrosion resistance and fatigue resistance. Still, their vibration behavior is relatively complex and may cause fatigue vibration damage, so it is essential to analyze the vibration characteristics of composite cylindrical shells. The purpose of this paper is to analyze the vibration characteristics of multilayer composite cylindrical shells subjected to external pressures and having different interlayer thickness ratios and provide some theoretical basis for the fatigue damage prediction of cylindrical shell casing to ensure the safety and stability of the engine during flight.

Firstly, the vibration differential equation with external pressure is established based on Soedel theory considering nonlinear effects, while four symmetric boundary conditions are chosen to constrain the cylindrical shell. Then the Rayleigh–Ritz method, which is more efficient and accurate in calculating large structural systems, is applied to solve the problem, and the theoretical model of three-layer cylindrical shell under external pressure is established. The accuracy of the model is verified by comparing the data with the specialized literature. Subsequently, the effects of different external pressures and different thickness-to-diameter ratios, different length-to-diameter ratios and different interlayer thickness percentages on the natural frequency of multilayer composite cylindrical shells were investigated by control variable analysis.

The conclusions obtained show that the external pressure increases the natural frequency of the cylindrical shell and that the frequency characteristics of the cylindrical shell vary for different boundary conditions. The effect of length-to-diameter ratio, thickness-to-diameter ratio and the percentage of the thickness of the intermediate layer on the natural frequency of the cylindrical shell are significantly increased under external pressure. Because the presence of external pressure increases the frequency of the cylindrical shell by about 70%, it has almost no effect on the frequency at the minimum number of circumferential waves, and the effect on the frequency at the maximum number of circumferential waves is reduced to about 50%. The frequencies in the SL-SL boundary condition are all in perfect agreement with the S-S boundary condition under the influence of different influencing factors.

In this paper, the effect of external pressure and the natural properties of the cylindrical shell under external pressure on the cylindrical shell’s frequency is considered, emphasizing the effect of different layer thickness ratios on the frequency. This paper aims to summarize the changing law between the natural frequency of the cylindrical shell itself and different design parameters during the flight pressure process. Reliable theoretical predictions are provided for analyzing the vibrational behavior of shells subjected to external pressures in aerospace, as well as a database for the practical production of cylindrical shells.

Over the past decade, artificial intelligence (AI) technologies have rapidly advanced organizational management, with many organizations adopting AI-based algorithms to enhance employee management efficiency. However, there remains a lack of sufficient empirical research on the specific impacts of these algorithmic management practices on employee behavior, particularly the potential negative effects. To address this gap, this study constructs a model based on the psychological ownership theory, aiming to investigate how algorithmic management affects employees’ knowledge hiding.

This study validates the model through a situational experiment and a multi-wave field study involving full-time employees in organizations implementing algorithmic management. Various analytical methods, including analysis of variance, regression analysis and path analysis, were used to systematically test the hypotheses.

The study reveals that algorithmic management exerts a positive indirect influence on knowledge hiding through the psychological ownership of personal knowledge. This effect is particularly pronounced when employees have lower organizational identification, highlighting the critical role of organizational culture in the effectiveness of technological applications.

This study is among the first empirical investigations to explore the relationship between algorithmic management and employee knowledge hiding from an individual perception perspective. By applying psychological ownership theory, it not only addresses the current theoretical gap regarding the negative effects of algorithmic management but also provides new theoretical and empirical support for the governance and prevention of knowledge hiding within organizations in the context of AI algorithm application. The study highlights the importance of considering employee psychology (i.e. psychological ownership of personal knowledge) and organizational culture (i.e. organizational identification) under algorithmic management. This understanding aids organizations in better managing knowledge risks while maximizing technological advantages and effectively designing organizational change strategies.

Green innovation in human-centric smart manufacturing (HSM-GI) has emerged as a new paradigm in innovation management for Industry 5.0. The evaluation analysis method is crucial for measuring the development progress and guiding continual improvements of HSM-GI. Since this process of HSM-GI can be regarded as complex and interactive, a holistic picture is often required to describe the interrelations of its antecedents and consequences. In this respect, this study aims to construct a causality network indicator system and proposes a synergy evaluation method for HSM-GI.

Firstly, based on the Driver force-State-Response (DSR) causal-effect framework, this study constructs a holistic indicator system to analyze the interactions between environmental and human concerns of HSM-GI. Secondly, owing to the imprecision of human cognition and synergy interaction in the evaluation process, a flexible hesitant fuzzy (HF) superiority-inferiority synergetic evaluation method is presented. This method quantifies the strengths of causal relationships and expresses the incentives and constraints attitudes of humans. Finally, the proposed framework is applied to six HSMs in the electronic technology industry.

The driving force and state of the HSM-GI system exhibit an upward trend, while the response continues to decline due to changing market demands. The order and synergy degree have shown an increasing trend during 2021–2023, particularly significant for BOE and Haier Smart Home. HSM-GI systems with higher scores mostly have functional coordination and a coherent synergy structure.

This study demonstrates the proposed approach’s applicability and assists policymakers in formulating targeted strategies for green innovation systems.

This study aims to explore whether top management team (TMT) faultlines affect corporate digitalization and what the impact mechanism is, thus effectively promoting the digital transformation of enterprises from the perspective of optimizing TMT structure.

This study sampled companies that were listed in China between 2011 and 2020. Using the two-way fixed effect model, it empirically tests the impact of TMT faultlines on the digital transformation of enterprises.

TMT task-related faultline significantly positively impacts enterprise digital transformation, while the bio-demographic faultline has a significant negative effect. The regulatory role played by Chief Executive Officer (CEO) power intensity in the relationship between the bio-demographic faultline and digital transformation is a negative one. The above relationship is strongly influenced by industry technical sophistication, corporate location and listing board.

The research has promoted the development of the upper echelons theory in the context of digitalization. Moreover, it enlightens the research of digital transformation’s influencing factors and mechanisms. However, no suitable mediating variable was found.

This research has significant implications for managers to optimize the internal structure of the TMT according to different enterprises’ business strategies in order to establish an efficient management team.

This study provides a new theoretical framework for TMT’s role in enterprise digital transformation. Further, it makes a beneficial exploration of the boundary and situational conditions of their relationship.

This paper aims to explore the impact of Sc element on the microstructure and corrosion properties of Mg-0.5Zn alloy.

Three kinds of Mg-0.5Zn-xSc (x = 0.1, 0.3 and 0.5 Wt.%) alloys were obtained, and the microstructure and corrosion properties were both analyzed.

As the Sc concentration increases, the corrosion resistance of the alloys initially improves and subsequently deteriorates. The trace addition of Sc can effectively reduce the grain size of Mg-Zn-Sc alloys and enhance the density of the corrosion products film. Consequently, an appropriate amount of Sc can reduce the corrosion rate of Mg-0.5Zn alloy.

However, the addition of Sc also introduces the second phase particles in the alloy, leading to galvanic corrosion, which adversely affects the corrosion resistance of Mg-0.5Zn alloy. Therefore, the amount of Sc added should be carefully controlled.

Drawing upon the Conservation of Resources theory and Relational Demography Theory, we examine the crossover of supervisor family experiences to subordinates in the workplace. We posit that supervisor family-to-work enrichment and conflict influence subordinate perceptions of supervisor support for work–family, which, in turn, positively affects subordinate work engagement and job satisfaction and negatively affects subordinate turnover intentions. The effects of supervisor family-to-work enrichment and conflict on perceptions of supervisor support are respectively suggested to be strengthened and weakened by the demographic similarity between the supervisor and the subordinate.

Using a sample of 496 employees nested within 83 supervisors from China, we conducted a multilevel analysis.

Our results indicate that supervisor family-to-work conflict and supervisor family-to-work enrichment have negative and positive effects (respectively) on subordinates’ perceptions of supervisor work–family support, and this effect is moderated by low, rather than high, similarity in the supervisor–subordinate dyad. An overall indirect effect of supervisor family-to-work enrichment and family-to-work conflict on subordinate work engagement, job satisfaction and turnover intentions through the mediator of perceived supervisor work–family support is also confirmed.

From a practical standpoint, our research emphasizes the importance for organizations to support supervisors in achieving work–family balance in order to promote positive employee work-related outcomes.

Our study contributes to work–family literature by unraveling how and when resources may travel through supervisors to affect the generation of new resources (i.e. supervisor support for work–family) and ultimately affect subordinate outcomes in the workplace.

This study aims to examine how the parent firm’s foreign direct investment (FDI) motive influences the roles of corporate boards and CEO appointment of foreign subsidiaries in the context of emerging market multinational enterprises (EMNEs). Based on the agency and resource dependence theories, foreign subsidiary boards mainly serve two governance roles: an internal role focusing on monitoring subsidiary operations and resource flows with parent firms and an external role aimed at securing local operational effectiveness. This paper specifically examines the composition of foreign subsidiary boards in terms of board independence and expatriate director ratio, and whether the CEO is an expatriate, which reflects the emphasized role.

This paper collects data on listed foreign subsidiaries of Chinese MNEs between 2005 and 2021. The final sample includes 754 subsidiary-year observations across 20 host economies. The analysis is conducted using Hausman–Taylor estimation.

This paper finds that strategic asset-seeking FDI motive is associated with a lower expatriate director ratio, a higher independent director ratio and a higher likelihood of hiring nonexpatriate CEOs. In contrast, foreign subsidiaries established with the motive of institutional escape to tax havens result in a higher expatriate director ratio, lower independent director ratio and lower likelihood of hiring nonexpatriate CEOs.

To the best of the authors’ knowledge, this study is the first to explore how FDI motives influence board composition of foreign subsidiaries and appointment of subsidiary CEOs. Theoretically, this paper draws upon agency theory and resource dependence theory to extend their application to foreign subsidiaries of EMNEs. The findings enhance the understanding of international corporate governance.