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Under the influence of loading, manufacturing, installation and other factors, the axis of sleeve bearing and journal will not be aligned, which will have a great impact on running stability and life of bearing. The existence of oil groove can effectively improve the life of sleeve bearing and working efficiency. The lubrication performance of two and three grooves sleeve bearing considering journal misalignment is analyzed.

To solve the difference of discontinuous position of oil film thickness, it is necessary to use the flow balance relationship in the finite control space, and oil film thickness equation of multi-groove sleeve bearing considering journal misalignment is gained.

The friction and bearing capacity of journal bearing with oil groove increase with the increase of journal inclination angle. At the same journal inclination angle, the bearing capacity of two-axial groove journal bearing is larger than that of three-axial groove journal bearing, but the friction of two-axial groove journal bearing shows the trend of the first bigger and then smaller than that of three-axial groove journal bearing.

The research has great significance to optimize bearing lubrication performance and increase bearing working life.

Supplier evaluation is a part of logistic management. In the present era, resilient supply chain performance (RSCP) assessment of the vendor enterprise is respected as a hot topic. The purpose of this paper is to enable the managers to map the performance in percentage system and also enabling managers for identifying the weak indices-metrics, which need to be improved up to ideal or standard level and strong indices-metrics.

The authors found two research gaps via a literature survey. The first research gap revealed that the performance of a resilient supplier is computed solely in terms of a fuzzy mathematical scale. The articles are not yet published, which could measure the RSCP in percentage. The second research gap argued about the mitigation of the multi-level hierarchical resilient vendor/supplier evaluation framework for materializing RSCP and identifying weak and strong performing indices-metrics. To compensate the both research gaps, the authors developed a novel fuzzy gain-loss evolutionary computational approach to assess the performance of a firm in percentage. Next, a revised ranking technique coupled with trapezoidal fuzzy set based fuzzy performance importance index is implemented on the framework to seek weak and strong indices-metrics. The performance loss of each metric using the ideal solution concept considering the attitude of decision makers is also revealed.

The authors found the RSC performance of supplier firm 74 per cent, whereas performance loss 26 per cent, while actual performance is compared with standard fuzzy performance index (SFPI). Performance loss 26 per cent can be compensated by improving the performance of weak indices-metrics.

The novelty of the paper is that the authors used the ideal solution concept to compute the SFPI and compare it with actual FPI for evaluating the gain and loss of resilient supplier firm in percentage and identify weak and strong indices so that managers can improve the performance of weak indices. The work possesses the significant for all organizations, as research work enables the managers to map and improve the RSC performance of any vendor firm in future. The presented work considers the case of an automobile parts supplier industry to validate the developed approach.

Extant research has paid considerable attention to the effects of enterprise social media (ESM) on employees' work attitudes and outcomes, yet the authors know little about the influence of job demands arising from the implementation of ESM. Drawing on resource allocation theory, the purpose of this study is to unravel how ESM-related job demands influence employee outcomes.

This study conducts a two-wave time-lagged survey of 223 employees from 53 teams in 14 financial service firms in China to test the conceptual model.

The findings of this paper indicate that ESM-related job demands have indirect effects on employee outcomes (i.e. job satisfaction and work–family conflict), and emotional exhaustion plays an intermediary role in these relationships. Specifically, ESM-related job demands have a U-shaped effect on emotional exhaustion.

This study combines job demands with ESM research and clarifies the mechanism behind how ESM-related job demands at different intensity affect employee outcomes from a new perspective. Moreover, this study’s findings suggest several beneficial courses of action for managers to take advantage of ESM.

The purpose of this review is to systematically understand the development of enterprise social media (ESM) research, quantitatively analyze the landscape and track the development of ESM literature and reveal new trends and challenges in ESM research.

Based on 321 relevant literature studies (2005–2020) collected from the Web of Science core collection, the visualization tool CiteSpace is used to conduct bibliometric cocitation and cooccurrence analyses to quantify and visualize the landscape and evolution of ESM research.

Through analyzing the author cocitation network, document cocitation network, journal cocitation network and keywords cooccurrence network, this review proposes an integrated research framework, which highlights major purposes, antecedents and consequences of ESM use in organizations and presents future research trends of ESM research.

Different from the existing qualitative review of ESM, this review adopts bibliometric review to quantify and visualize the landscape of ESM research.

The purpose of this paper is to improve the operation and maintenance intelligence of power systems, and summarize the transmission line robots and their key technologies. High-voltage power cables are important channels for power transmission systems. Their special geographical environment and harsh natural environment can lead to many different faults. At present, such special operations in dangerous and harsh environments are performed manually, which have not only high labor intensity and low work efficiency but also great personal safety risks.

For maintenance works that are far away from the tower, power outages are required. With the increasing evaluation of transmission quality and operational safety, and the urgent need for automation and operation of modern power systems, the contradiction between this manual operation and modern high-quality power transmission has become increasingly prominent. An effective method to replace the manual maintenance work is to use the mobile robot to carry the operation manipulator and its end tool, that is, the live maintenance robot.

Some achievements have been made in the key technologies of live maintenance robots, the work to be done to meet the basic requirements of complex and changeable line environment and practical application. Based on the existing research results of live overhaul robot, the follow-up research will focus on the practical application needs and the frontier of scientific and technological development, and truly realize the human–machine integration between live overhaul robot–human working environment. Only in this way can the robot better serve the operation and maintenance of the power system.

This paper reviews the system platform, operation function, structural characteristics and key technologies involved in the power cable robot, and the combination of live maintenance robots and modern high-tech such as big data and cloud computing is also given, and finally, the future development direction of the special operation robot is pointed out.

The purpose of this paper is to focus on the production of scaffolds with specific morphology and mechanical behavior to satisfy specific requirements regarding their stiffness, biological interactions and surface structure that can promote cell-cell and cell-matrix interactions though proper porosity, pore size and interconnectivity.

This case study was focused on the production of multi-layered hybrid scaffolds made of polycaprolactone and consisting in supporting grids obtained by Material Extrusion (ME) alternated with electrospun layers. An open source 3D printer was utilized, with a grain extrusion head that allows the production and distribution of strands on the plate according to the designed geometry. Square grid samples were observed under optical microscope showing a good interconnectivity and spatial distribution of the pores, while scanning electron microscope analysis was used to study the electrospun mats morphology.

A good adhesion between the ME and electrospinning layers was achieved by compression under specific thermomechanical conditions obtaining a hybrid three-dimensional scaffold. The mechanical performances of the scaffolds have been analyzed by compression tests, and the biological characterization was carried out by seeding two different cells phenotypes on each side of the substrates.

The structure of the multi-layered scaffolds demonstrated to play an important role in promoting cell attachment and proliferation in a 3D culture formation. It is expected that this design will improve the performances of osteochondral scaffolds with a strong influence on the required formation of an interface tissue and structure that need to be rebuilt.

The purpose of this research is to design and develop a technique for polyphase code design for the radar system.

The proposed fractional harmony search algorithm (FHSA) performs the polyphase code design. The FHSA binds the properties of the harmony search algorithm and the fractional theory. An optimal fitness function based on the coherence and the autocorrelation is derived through the proposed FHSA. The performance metrics such as power, autocorrelation and cross-correlation measure the efficiency of the algorithm.

The performance metrics such as power, autocorrelation and cross-correlation is used to measure the efficiency of the algorithm. The simulation results show that the proposed optimal phase code design with FHSA outperforms the existing models with 1.420859, 4.09E−07, 3.69E−18 and 0.000581 W for the fitness, autocorrelation, cross-correlation and power, respectively.

The proposed FHSA for the design and development of the polyphase code design is developed for the RADAR is done to reduce the effect of the Doppler shift.