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The possibilities increasing the wear resistance of friction pair radial lip seal/shaft were tested using fluoroligomeric materials and selective transfer technologies. Measurements of friction moment, temperature in contact spot and wear of friction surfaces show that fluoroligomeric coat and selective transfer technologies (metallpolymeric oil additives and NABA‐coat on shaft) can considerably decrease the friction losses and increase the wear resistance of friction pair. The microscopic analysis of surfaces shows that using tribotechnical materials in contact spot of friction surfaces forms virtually different structures which can explain the different efficiency mechanisms of the mentioned materials. These tests show that in friction pair radial lip seal/shaft the tribomaterials could be used which create selective transfer effect and have regenerating properties.

The aim of this paper is to investigate the regularities and longevity of the recovering without takedown of the friction pairs in internal combustion engines using the lubricants with metal cladding materials (MCM).

Recovering of friction pairs of internal combustion engines by MCM was investigated using field experiments. Four automobiles were investigated. The wear of those details was evaluated according to the compression in the cylinders. The influence of MCM on the amount of toxic materials (carbon monoxide and hydrocarbons) in the exhaust gas was evaluated after measurements with a gas analyser.

Using MCM can recover on average 60 per cent of lost compression ΔP_m. MCM decreases compression dispersion among separate cylinders of the engine. Compression of recovered engine cylinders decreases according to logarithmic function. Increment of cylinders' compression ΔP_d decreased on average 40‐50 per cent after 10,000 km car run. The recovering of the details of a cylinder‐piston group with MCM decreases the emission of toxic exhaust gas to the environment.

No laboratory investigations of MCM regeneration of friction pairs were performed which could evaluate the influence of different factors on the regeneration quality.

Investigations on the use of MCM for recovering the cylinder‐piston details of engines show the expedience in using such materials during periodic technical service of engines when the lubricants are changed.

Investigations of regenerating engines by MCM using field experiments were performed for the first time.

The purpose of this paper is to investigate the influence of fluor‐oligomeric coat on the mechanical properties of steel surface, as well as the chemical interaction of fluor‐oligomeric films with surface and theoretical‐phenomenological interpretation of structural processes in friction surface.

Four groups of specimens were studied: two groups of specimens without any wear tests – initial steel specimen as control version and a specimen which was ten times coated by fluor‐oligomer, and two groups of specimens, which were tribologically tested for one million cycles – without any coating and coated specimens. Closed kinematical profile scheme roller‐roller of steel 45 was chosen for tribological tests. Wear of friction surface after those tests was investigated. The interaction between fluor‐oligomer and iron was studied by means of Mössbauer spectroscopy. The micro‐hardness of matrix was also measured.

Affecting the surface of steel by the fluor‐oligomer and friction produces the complicated processes of carbide decay and formation occur. The mechanisms are found which are related to the weakening of chemical bond in steel during the absorption, to the generation of microscopic ruptures, to the decrease (30‐50 per cent) of the amount of carbides and its increase during the friction (up to 50 per cent). The mechanical effect which causes the regeneration of carbides during friction is revealed. Tribological efficiency of fluor‐oligomeric coats (five times lower wear of coated specimens) is explained by the balance of three processes – the softening of matrix during adsorption, the detention of dislocations, and formation of hard particles in the matrix.

The complex mechanism of the increase of wear resistance is explained by filling of ductile matrix with carbide particles.

Combining the coping theory and social support theory, this study aims to reveal users' coping strategies for mobile fitness app (MFA) engagement and fitness intentions with a rigorous and comprehensive hybrid research approach.

A three-stage hybrid research design was employed in this study. In the first stage, this study utilized structural equation modeling (SEM) to investigate the associations between coping resources and coping outcomes. A post hoc analysis was conducted in the second stage to unveil the reasons behind the insignificant or weak linkages. In the third stage, the fuzzy-set qualitative comparative analysis (fsQCA) technique was applied to explore the various configurations of coping resources that lead to the coping outcomes.

The results in the three stages verify and compensate each other. The SEM results confirm the presence of two coping strategies in MFA, highlighting the importance of the intertwining of the strategies, and the post hoc analysis unveils the mediating role of positive affect. Moreover, the fsQCA results reinforce and complement the SEM findings by revealing eight alternative configurations that are sufficient for leading to users' MFA engagement and fitness intention.

This study offers a prominent methodological paradigm by demonstrating the application of multi-analysis in exploring users' coping strategies. In addition, the study also advances the understanding of the complexity of the mechanism that determines users' behavioral decisions by presenting a comprehensive interpretation.

Fitness games, as a medium that combines playfulness and usefulness for exercise, face challenges in sustaining long-term user engagement. Currently, there is limited research exploring factors influencing users' continued intention to use from the perspective of user experience. Therefore, this study aims to investigate the priority of various user experience attributes of fitness games in promoting users' sustained engagement and to construct a user behavior model, offering theoretical guidance for designers and businesses.

This study distributed 441 survey questionnaires and, based on the fundamental characteristics of external games, established a model for users' continued intention to use external games. It explores the impact of various gaming elements on users' continued intention to use fitness games and the relationships between these elements.

The study indicates that usefulness, functional quality, and ease of use directly influence players' intention to continue playing external games. Social interactions, technical quality, and playfulness do not have an impact on the continued intention to use.

This research breaks away from the bias of previous studies overly focusing on playfulness in games. It fills the research gap regarding the continued intention to use fitness games and provides insights into the design and operation of fitness games.

Exoskeletons are moving into industries with the potential to reduce muscle strains and prevent occupational injuries. Although exoskeletons have been designed and tested in laboratory settings, rare empirical studies of their application in construction have been reported. Therefore, the purpose of this study is on in a real-life setting testing the applicability of adopting exoskeletons in the construction industry.

A feasibility study of exoskeletons in construction is conducted by testing a passive exoskeleton, designed for shoulder support. Five bricklayers tested in a two-month period the exoskeleton, each wearing it for a three-day period while carrying out normal work activities. Test data in terms of interviews were collected and analyzed using qualitative content analysis.

The application of exoskeletons in construction revealed several limitations, where the two primary ones are the exoskeleton is not designed while considering the tasks of a bricklayer causing several challenges and the exoskeleton only supports a single upward motion while limiting other movements and even counteracted when a downward movement was necessary.

The identified challenges could easily have been revealed by coupling the design and testing of exoskeletons to actual application. Thus, the design approach needs to be reversed. Instead of designing an exoskeleton to support a specific body part or motion and then identifying where it is applicable, it should target specific industries and focus on the actual work and movements and the necessary support. As part of the change, the design metrics should be reevaluated to reflect the work to support.

This paper aims to explore the role of perceived organizational injustice (POI) leading to workplace conflict in determining organizational performance (OP) among healthcare employees. This paper also examines the serial mediating effects of moral disengagement (MD) and knowledge hiding (KH).

In all, 244 public and private hospital employees in Pakistan provided the data set.

According to partial least squares-structural equation modeling findings, the negative association between POI and OP was serially mediated by KH and MD. The recovery process underlying the linkage between POI and OP is tested and highlighted in this paper as a first step in unraveling it.

The findings highlight the significance of taking moral and KH models into account when attempting to understand the moral cognitive processes that employees go through when they see injustice. Organizations should guarantee the equitable distribution of incentives and resources, as distributive and procedural justices are concerned with organizations.

By directing actions meant to prevent MD and KH, the findings may potentially inspire new, more focused treatments to safeguard patient safety and avoid losses in the healthcare industry. One way to reduce unethical conduct and MD is to have people declare or agree to a code of ethics.