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This paper aims to investigate how perceived working conditions affect employee performance, including safety compliance and task performance, through employee well-being (i.e. job satisfaction) in the context of the coal mining sector in China.

This paper uses the job demands-resources model to test the relationships between working conditions, including job demands (work pressure as a challenge demand and perceived risks and hazards in the workplace and ineffectiveness of the safety system as hindrance demands), job resources (interpersonal harmony), job satisfaction and performance. This study adopts a two-wave design with a three-month lag to reduce possible common method bias.

Employees who experienced high level of challenge demands, e.g. time pressure workload, reported higher levels of task performance, and this positive relationship seemed to be robust. There is a direct effect of perceived ineffectiveness of the safety system on task performance, while the relationship between perceived risks and hazards and task performance was fully mediated by job satisfaction. Challenge demands, i.e. work pressure, did not impact much on employees’ well-being, and thus job satisfaction did not mediate the relationship between work pressure and performance. Perceived ineffectiveness of the safety system was negatively associated with safety compliance. This result is not surprising since a lack of effective safety system reflects management’s ignorance of workplace safety, which demotivates employees to enact safe behaviors. In contrast, the presence and implementation of an effective safety system would be interpreted by employees as management exhibiting a high level of commitment. Work pressure was positively not negatively related to safety compliance. One possible explanation for this finding is that the effects of work pressure on safety compliance behaviors might be dependent on contextual factors such as safety climate. Interpersonal harmony moderated the relationships between work pressure and employee performance (both safety compliance and task performance) and the relationship between perceived risks and hazards and task performance, but the role of interpersonal harmony appeared more complex. There was no significant correlation between challenging job demands and individual employee performance when there were higher levels of interpersonal harmony. The relationship between perceived risks and hazards, a hindrance job demand and task performance became positive as interpersonal harmony increased but negative as interpersonal harmony decreased.

This paper provides a robust integrative theoretical framework that better explains the various types of job demands and job resources in the working environment of coal mining sector in China and their relationships to employee performance. The findings also offer valuable guidance for managers trying to identify effective ways to enhance employee performance and safety in the workplace.

This paper aims to study the agent learning from expert demonstration data while incorporating reinforcement learning (RL), which enables the agent to break through the limitations of expert demonstration data and reduces the dimensionality of the agent’s exploration space to speed up the training convergence rate.

Firstly, the decay weight function is set in the objective function of the agent’s training to combine both types of methods, and both RL and imitation learning (IL) are considered to guide the agent's behavior when updating the policy. Second, this study designs a coupling utilization method between the demonstration trajectory and the training experience, so that samples from both aspects can be combined during the agent’s learning process, and the utilization rate of the data and the agent’s learning speed can be improved.

The method is superior to other algorithms in terms of convergence speed and decision stability, avoiding training from scratch for reward values, and breaking through the restrictions brought by demonstration data.

The agent can adapt to dynamic scenes through exploration and trial-and-error mechanisms based on the experience of demonstrating trajectories. The demonstration data set used in IL and the experience samples obtained in the process of RL are coupled and used to improve the data utilization efficiency and the generalization ability of the agent.

During the construction process of the China Railway Track System (CRTS) I type filling layer, the nonwoven fabric bags have been used as grouting templates for cement asphalt (CA) emulsified mortar. The porous structure of nonwoven fabrics endowed the templates with breathability and water permeability. The standard requires that the volume expansion rate of CA mortar must be controlled within 1%–3%, which can generate expansion pressure to ensure that the cavities under track slabs are filled fully. However, the expansion pressure caused some of the water to seep out from the periphery of the filling bag, and it would affect the actual mix proportion of CA mortar. The differences in physical and mechanical properties between the CA mortar under track slabs and the CA mortar formed in the laboratory were studied in this paper. The relevant results could provide important methods for the research of filling layer materials for CRTS I type and other types of ballastless tracks in China.

During the inspection of filling layer, the samples of CA mortar from different working conditions and raw materials were taken by uncovering the track slabs and drilling cores. The physical and mechanical properties of CA mortar under the filling layer of the slab were systematically analyzed by testing the electrical flux, compressive strength and density of mortar in different parts of the filling layer.

In this paper, the electric flux, the physical properties and mechanical properties of different parts of CA mortar under the track slab were investigated. The results showed that the density, electric flux and compressive strength of CA mortar were affected by the composition of raw materials for dry powders and different parts of the filling layer. In addition, the electrical flux of CA mortar gradually decreased within 90 days’ age. The electrical flux of samples with the thickness of 54 mm was lower than 500 C. Therefore, the impermeability and durability of CA mortar could be improved by increasing the thickness of filling layer. Besides, the results showed that the compressive strength of CA mortar increased, while the density and electric flux decreased gradually, with the prolongation of hardening time.

During 90 days' age, the electrical flux of the CA mortar gradually decreased with the increase of specimen thickness and the electrical flux of the specimens with the thickness of 54 mm was lower than 500 C. The impermeability and durability of the CA mortar could be improved by increasing the thickness of filling layer. The proposed method can provide reference for the further development and improvement of CRTS I and CRTS II type ballastless track in China.

The construction of cement asphalt (CA) emulsified mortar can obviously disturb the slab status after the fine adjustment. To decrease or eliminate the influence of CA mortar grouting on track slab geometry status, the effects of grouting funnel, slab pressing method, mortar expansion ratio, seepage ratio and grouting area on China Railway Track System Type (CRTS I) track slab geometry status were discussed in this paper.

Combined with engineering practice, this paper studied the expansion law of filling layer mortar, the liquid level height of the filling funnel, the pressure plate device and the amount of exudation water and systematically analyzed the influence of filling layer mortar construction on the state of track slab. Relevant precautions and countermeasures were put forward.

The results showed that the track slab floating values of four corners were different with the CA mortar grouting and the track slab corner near CA mortar grouting hole had the maximum floating values. The anti-floating effect of “7” shaped slab pressing device was more efficient than fixed-joint angle iron, and the slab floating value could be further decreased by increasing the amount of “7” shaped slab pressing devices. After CA mortar grouting, the track slab floating pattern had a close correlation with the expansion rate and water seepage rate of CA mortar over time and the expansion and water seepage rate of the mortar were faster when the temperature was high. Furthermore, the use of strip CA mortar filling under the rail bearing platform on both sides could effectively reduce the float under the track slab, and it could also save mortar consumption and reduce costs.

This study plays an important role in controlling the floating values, CA mortar dosage and the building cost of projects by grouting CA mortar at two flanks of filling space. The research results have guiding significance for the design and construction of China's CRTS I, CRTS II and CRTS III track slab.

The purpose of this study is to determine the dimensions of cultural differences, which are theoretically most relevant to contract functions in international marketing. Moreover, the contradiction between contract governance and opportunism is reconciled by exploring the boundary conditions of specific cultural differences.

The authors obtained 235 bilateral data provided by Chinese exporters and overseas distributors. The authors matched a secondary data set with the questionnaire data, which were analyzed by confirmatory factor analysis and a hierarchical moderation model.

The results demonstrate that while contract specificity is less successful in this area, contingency adaptability is useful in reducing opportunism. Moreover, as the national cultural differences regarding uncertainty avoidance, power distance or individualism-collectivism become more pronounced. One contractual dimension will be more effective at curbing opportunism, while the other will be less effective.

Despite sample limitations, to the best of the authors’ knowledge, this paper is the first to theoretically identify the effect of cultural difference dimensions in contract governance, unlike past studies taking cultural differences as an aggregated variable. Furthermore, by exploring the boundary conditions of cultural differences, this paper effectively reconciles the conflicting findings on the relationship between contract governance and opportunism in various cultural context.

Exporters’ managers can design contingency adaptability to complement the limitations of contract specificity and consider cultural differences’ contingency effects.

First, the authors identify cultural differences dimensions related to contract governance, refining and emphasizing the research context. Second, comparing the efficacy of contract specificity and contingency adaptability in specific cultural context can show which contract is better at preventing opportunism.

Auxetics metamaterials show high performance in their specific characteristics, while the absolute stiffness and strength are much weaker due to substantial porosity. This paper aims to propose a novel auxetic honeycomb structure manufactured using selective laser melting and study the enhanced mechanical performance when subjected to in-plane compression loading.

A novel composite structure was designed and fabricated on the basis of an arrowhead auxetic honeycomb and filled with polyurethane foam. The deformation mechanism and mechanical responses of the structure with different structural parameters were investigated experimentally and numerically. With the verified simulation models, the effects of parameters on compression strength and energy absorption characteristics were further discussed through parametric analysis.

A good agreement was achieved between the experimental and simulation results, showing an evidently enhanced compression strength and energy absorption capacity. The interaction between the auxetic honeycomb and foam reveals to exploit a reinforcement effect on the compression performance. The parametric analysis indicates that the composite with smaller included angel and higher foam density exhibits higher plateau stress and better specific energy absorption, while increasing strut thickness is undesirable for high energy absorption efficiency.

The results of this study served to demonstrate an enhanced mechanical performance for the foam filled auxetic honeycomb, which is expected to be exploited with applications in aerospace, automobile, civil engineering and protective devices. The findings of this study can provide numerical and experimental references for the design of structural parameters.

This study investigates how role overload in the sharing economy leads to emotional exhaustion, which restricts value co-creation activity, and also investigates the moderating effect of perceived platform support.

Two experimental investigations and field research questionnaires were given to respondents with shared mobility industry expertise.

First, role overload detrimentally affects service providers' value co-creation behavior; second, emotional exhaustion acts as a mediator between role overload and value co-creation behavior; and finally, perceived platform support moderates the adverse effect of role overload on emotional exhaustion.

To the best of the authors' knowledge, this study is the first to explore the antecedents of value co-creation behavior from the service provider's perspective, extending the application of COR theory in a sharing economy context.

First, alternative mediators between role overload and emotional exhaustion were not identified. Second, other dimensions of role overload and their impacts were not examined. Lastly, this study did not explore broader perspectives beyond algorithms.

This study recommends that managers reduce role overload ex ante in terms of clarifying responsibilities and obligations, providing substantive resource support and rationalizing order allocation, respectively.

This study aims to investigate the impact of digital orientation (DO) on organizational resilience (OR) and explore the contingency effects of human resource slack and nature of enterprise ownership.

The model hypotheses were tested using fixed effects regression on panel data collected from Chinese A-share listed manufacturing firms spanning from 2007 to 2020.

DO has a positive effect on OR. Human resource slack positively moderates the relationship between DO and OR. Additionally, DO enhances OR more effectively in non-state-owned firms than in state-owned firms.

This study relies on data from a single industry from a single country.

The study supports that firms facing uncertainty, risk and pressure should promptly develop their DO strategy. Firms can derive greater resilience from implementing a DO strategy when they have a high-level human resource pool. State-owned enterprises will benefit from a DO strategy if they make some adaptive changes in leadership, structure, culture and mindset aspects.

This study is the first to examine the relationship between DO and OR, contributing to the existing literature on digital transformation and organizational resilience. It offers valuable insights for practitioners and policymakers seeking to adapt their organizations for the digital era and foster predictive, defensive and growth responses strategies in a dynamic business environment.

This study aims to discuss the influences of surface severe plastic deformation (S²PD) on the electrochemical corrosion, pitting corrosion, intergranular corrosion, stress corrosion cracking of aluminum (Al) alloys and attempt to correlate the microstructural/compositional changes with the performances.

This study provides a novel gradient design of structure/composition caused by S²PD for the purpose of enhancing Al alloys’ corrosion resistance.

S²PD has a significant effect on corrosion behavior of Al alloys through tuning the grain size, residual stress, composition, grain boundary phase and second phase particle distribution.

Although Al alloys are known to form a protective Al₂O₃ film, corrosion is a major challenge for the longevity of Al structures across numerous industries, especially for the infrastructures made of high-strength Al alloys. Traditional strategies of improving corrosion resistance of Al alloys heavily relied on alloying and coatings. In this review, gradient design of structure/composition caused by S²PD provides a novel strategy for corrosion protection of Al alloys, especially in the enhancement of localized corrosion resistance.

This review aims to give a critical view of the wheel/rail high frequency vibration-induced vibration fatigue in railway bogie.

Vibration fatigue of railway bogie arising from the wheel/rail high frequency vibration has become the main concern of railway operators. Previous reviews usually focused on the formation mechanism of wheel/rail high frequency vibration. This paper thus gives a critical review of the vibration fatigue of railway bogie owing to the short-pitch irregularities-induced high frequency vibration, including a brief introduction of short-pitch irregularities, associated high frequency vibration in railway bogie, typical vibration fatigue failure cases of railway bogie and methodologies used for the assessment of vibration fatigue and research gaps.

The results showed that the resulting excitation frequencies of short-pitch irregularity vary substantially due to different track types and formation mechanisms. The axle box-mounted components are much more vulnerable to vibration fatigue compared with other components. The wheel polygonal wear and rail corrugation-induced high frequency vibration is the main driving force of fatigue failure, and the fatigue crack usually initiates from the defect of the weld seam. Vibration spectrum for attachments of railway bogie defined in the standard underestimates the vibration level arising from the short-pitch irregularities. The current investigations on vibration fatigue mainly focus on the methods to improve the accuracy of fatigue damage assessment, and a systematical design method for vibration fatigue remains a huge gap to improve the survival probability when the rail vehicle is subjected to vibration fatigue.

The research can facilitate the development of a new methodology to improve the fatigue life of railway vehicles when subjected to wheel/rail high frequency vibration.