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The purpose of this paper is to examine the relationship between leader-member exchange (LMX) differentiation and team members’ job performance. The conceptual model developed in this paper also investigates the moderating role of the perception of organisational politics (POP) in affecting the association between LMX differentiation and team members’ job performance.

The authors collected data using a survey from 32 Chinese firms. The questionnaire included scales measuring LMX, POP, job performance, and demographic variables. The final sample consisted of 122 teams with 561 employees. The hypothesised relationships among variables were assessed using hierarchical linear modelling.

The results show that the higher the LMX differentiation, the lower the level of team members’ contextual performance. The authors also found that POP has a significant effect in positively moderating the relationships between LMX differentiation and team members’ contextual and task performances.

The conceptual model developed and verified in this paper provides essential insights for the research on LMX and job performance. Future studies are suggested to collect cross-national data to examine the conclusions of this study.

The association between LMX differentiation and team members’ job performance is moderated by the degree of POP.

This paper aims to review the literature on mobile information services. It considers only peer-reviewed papers published in English between 2004 and 2014.

The method of systematic review was adopted to collect and analyse the relevant literature. The searches were conducted during the last week of July 2014 on different databases, and in total, 76 papers were considered after applying inclusion and exclusion criteria.

Seven themes emerged: “introducing mobile libraries”, “reporting on current trends”, “exploring users’ perceptions of libraries’ mobile services”, “presenting libraries’ mobile services”, “presenting mobile technology use in libraries”, “reporting case studies” and “reporting on evaluation of libraries’ mobile services”. It is evident that research on mobile libraries is very recent and focuses mainly on raising the Library and Information Science profession’s awareness of providing mobile information services.

This literature review focused only on peer-reviewed papers published between 2004 and 2014 in English.

This paper summarises and critically presents the relevant literature on libraries offering mobile information services. It informs libraries and librarians’ understanding of recent developments in mobile technology for the successful provision of information services.

This study aims to tackle control challenges in soft robots by proposing a visually-guided reinforcement learning approach. Precise tip trajectory tracking is achieved for a soft arm manipulator.

A closed-loop control strategy uses deep learning-powered perception and model-free reinforcement learning. Visual feedback detects the arm’s tip while efficient policy search is conducted via interactive sample collection.

Physical experiments demonstrate a soft arm successfully transporting objects by learning coordinated actuation policies guided by visual observations, without analytical models.

Constraints potentially include simulator gaps and dynamical variations. Future work will focus on enhancing adaptation capabilities.

By eliminating assumptions on precise analytical models or instrumentation requirements, the proposed data-driven framework offers a practical solution for real-world control challenges in soft systems.

This research provides an effective methodology integrating robust machine perception and learning for intelligent autonomous control of soft robots with complex morphologies.

This paper aims to research the relationship between income gap (IG) and green economic growth based on the perspective of economic inequality.

Based on the panel data of 283 prefecture-level cities in China from 2011 to 2020, this paper uses the super slack based model (Super-SBM) to measure the efficiency of regional green economic growth, and constructs a regression model of the IG and regional green economic growth.

Firstly, the IG has an inhibitory effect on the growth of regional green economy (GE). Secondly, the relationship between the IG and regional green economic growth will be affected by the threshold value of income level. Thirdly, environmental regulation and government competition will increase the inhibitory effect of the IG.

According to the characteristics of China's regional economy, the researchers construct an empirical model of the IG and green economic growth to study their relationship, the threshold effect of income level and the moderating effect of environmental regulation and local government competition. The research content, methods and conclusions of this paper provide new evidence for the sustainable growth of China's regional GE.

The purpose of this paper is to provide a theoretical foundation for improving the selective laser melting (SLM) surface roughness. To improve the part’s surface quality during SLM process, the upper surface roughness of SLM parts was theoretically studied and the influencing factors were analyzed through experiments.

The characteristics of single track were first investigated, and based on the analysis of single track, theoretical value of the upper surface roughness would be calculated. Two groups of cubic sample were fabricated to validate SLM parts’ surface roughness, the Ra and relative density of all the cubic parts was measured, and the difference between theoretical calculation and experiment results was studied. Then, the effect of laser energy density on surface roughness was studied. At last, the SLM part’s surface was improved by laser re-melting method. At the end of this paper, the curved surface roughness was discussed briefly.

The SLM upper surface roughness is affected by the width of track, scan space and the thickness of powder layer. Measured surface roughness Ra value was about 50 per cent greater than the theoretical value. The laser energy density has a great influence on the SLM fabrication quality. Different laser energy density corresponds to different fabricating characteristics. This study divided the SLM fabrication into not completely melting zone, balling zone in low energy density, successfully fabricating zone and excessive melting zone. The laser surface re-melting (LSR) process can improve the surface roughness of SLM parts greatly without considering the fabricating time and stress accumulation.

The upper surface roughness of SLM parts was theoretically studied, and the influencing factors were analyzed together; also, the LSR process was proven to be effective to improve the surface quality. This study provides a theoretical foundation to improve the surface quality of SLM parts to promote the popularization and application of metal additive manufacturing technology.

This study aims to investigate and compare the influence of various fiber types (polypropylene, steel and glass) on the workability, mechanical properties, ductility, impact resistance, durability and microscopic properties of geopolymer concrete (GPC) with conventional concrete (CC).

The CC and GPC of M40 grade were incorporated with an optimum 1% of fibers and superplasticizers were added in a ratio of 2% by weight of the geopolymer binder. The slump cone and compaction factor tests were performed to analyze the workability. To evaluate the mechanical performance of GPC, the compressive strength (CS), split tensile strength (STS), flexural strength (FS) and modulus of elasticity (MOE) tests were performed. A falling weight impact test was performed to determine the impact energy (IE) absorbed, the number of blows for initial cracking, the number of blows for complete failure and the ductility aspect.

Fibers and superplasticizers significantly improve GPC properties. The study found that fibers reduce the brittleness of concrete, improving the impact and mechanical strength compared to similar-grade CC. The steel fibers-reinforced GPC has a 15.42% higher CS than CC after three days, showing a faster CS gain. After 28 days, GPC and CC have MOE in the range of 23.9–25.5 GPa and 28.8–30.9 GPa, respectively. The ultimate IE of the GPC with fibers was found to be 5.43% to 21.17% higher than GPC without fibers.

The findings of the study can be used to explore different combinations of raw materials and mix designs to optimize the performance of GPC.