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The purpose of this paper is to investigate the dynamic forming process of the micro dent fabricated by laser shock processing on 2024-T3 aluminum alloy. The effect of laser pluse energy on the deformation of micro dent was also discussed in detail.

It uses finite element analysis method and the corresponding laser shocking experiment.

The results demonstrate that the dynamic formation process of micro dent lasts longer in comparison with the shock wave loading time, and the depths of micro dents increase with the increasing laser energy. In addition, laser shocking with higher energy can result in more obvious pileup occurred at the outer edge of micro dent.

Surface micro dents can serve as fluid reservoirs and traps of the wear debris, which can decrease the effects of the wear and friction in rolling and sliding interfaces. The investigations can not only be propitious to comprehensively understand the forming mechanism of laser-shocked dent, but also be beneficial to get sight into the residual stress field induced by laser shocking.

There have been profound changes in the Portuguese national health system (NHS), instigated under the influence of managerialism and the new public management (NPM) “philosophy”. These changes have been in line with what has happened in other developed countries. At the beginning of the new century, important reforms that emphasised the efficient use of scarce resources were implemented. The objective of this study is to understand how nurses are adapting to a more managerial environment, one in which economic rationalism and market‐driven initiatives are the key principles behind the health reforms.

A qualitative study was developed, based on semi‐structured interviews with 83 nurses with managerial duties in ten hospitals in Portugal. All interviews were tape‐recorded and each interviewee's discourses were subjected to content analysis.

Data analysis led to the conclusion that under the new logic of the market and managerialism, these professionals have tried to (re)define their professionalisation route by emphasising the importance of care but also by trying to incorporate management as their dominant role in the social division of work. In reconfiguring their notion of professionalism, nurses were incorporating new practices in their day‐to‐day activities. This empirical study confirms that professionalism can also be conceptualised as a technology of self‐control being able to discipline professionals at the micro level.

This research is an empirical study based on the effects of managerialism on nurses with managerial duties in Portugal. This study contributes to a better understanding of the complex process of the professionalisation of nurses in a context of institutional change.

The purpose of this paper is to investigate the effect of round pits arrangement patterns on tribological properties of journal bearing. In this paper, the tribological behaviors of journal bearing with different arrangement patterns under lubrication condition were studied based on M-2000 friction and wear tester.

The friction and wear of journal bearing contact surface were simulated by ANSYS. The wear mechanism of bearing contact surfaces was investigated by the means of energy dispersive spectrum analysis on the surface morphology and friction and wear status of the journal bearing specimens by Scanning Electron Microscopy (SEM) and Energy Dispersive Spectrometer (EDS). Besides, the wearing capacity of the textured bearing was predicted by using the GM (1,1) and Grey–Markov model.

As the loads increase, the friction coefficient of journal bearing specimens decrease first and then increase slowly. The higher rotation speed, the lower friction coefficient and the faster temperature build-up. The main friction method of the bearing sample is three-body friction. The existence of texture can effectively reduce friction and wear. In many arrangement patterns, the best is 4# bearing with round pits cross-arrangement pattern. Its texturing diameters are 60 µm and 125 µm, and the spacing and depth are 200 µm and 25 µm, respectively. In addition, the Grey–Markov model prediction result is more accurate and fit the experimental value better.

The friction and wear mechanism is helpful for scientific research and engineers to understand the tribological behaviors and engineering applications of textured bearing. The wear capacity of textured bearing is predicted by using the Grey–Markov model, which provides technical help and theoretical guidance for the service life and reliability of textured bearing.

This study aims to study the effect of micro-groove texture geometric parameters on the lubrication characteristics of the tripod universal coupling.

The Navier–Stokes equation was used to analyse the influence of micro-groove geometric parameters on the coupling’s lubrication performance. Further, Kriging approximate model and neighborhood cultivation genetic algorithm (NCGA) were used to optimise the micro-groove geometric parameters and improve the coupling’s lubrication performance.

The results show that as the micro-groove depth and width increase, respectively, the oil film-bearing capacity first increases and then decreases; on the contrary, the friction coefficient first decreases and then increases. With the increase of the micro-groove inclination angle, the bearing capacity of the oil film first increases and then remains unchanged. At the same time, the friction coefficient first decreases and then increases slightly. The lubricating performance of the optimised coupling is significantly improved: the optimised oil film-bearing capacity increases by 12.5%, the friction coefficient reduces by 14% and the maximum oil film pressure increases by 4.3%.

At present, the grease lubrication performance of the micro-groove textured tripod universal coupling has not been studied. The micro-groove parameters are optimised, and the coupling’s lubrication performance is improved greatly by the Kriging model and NCGA algorithm. It is of great significance to extend the coupling’s fatigue life.

This paper aims to reveal the influence of the grooved texture parameters on the lubrication performance of circular pocket-roller pairs in cylindrical roller bearings.

In this paper, the thermal elastohydrodynamic lubrication mathematical model of the grooved texture circular pocket-roller pair was established, the finite difference method and successive over-relaxation method were used to solve the model, the influence of texture quantity, texture depth and texture area ratio on circumferential bearing capacity, friction coefficient, maximum temperature rise, stiffness and damping of the circular pocket-roller pairs were analyzed.

The results show that texture quantity, texture depth and texture area ratio significantly influence the static and dynamic characteristics of circular pocket-roller pairs. The suitable surface groove texture parameters can dramatically improve the circumferential bearing capacity, reduce the friction coefficient, inhibit the maximum temperature rise and increase the stiffness and damping of the circular pocket-roller pairs.

The research in this paper can provide a theoretical basis for the optimization design of pockets in cylindrical roller bearings to reduce friction and vibration.

The purpose of this paper is to propose a bearing replacement strategy which employs the Monte Carlo simulation method. In this contribution the method is used to estimate the economic impact on the selection of a particular bearing change strategy. The simulation demonstrates that it is possible to identify the most cost‐effective approach and thus suggests a suitable bearing replacement policy, which in turn allows engineers to develop the appropriate maintenance schedules for their company.

The paper develops the Monte Carlo method through a case study approach. Three case studies are presented. The first study is detailed and chronicles the design, development and implementation of the Monte Carlo method as a means of defining a bearing replacement strategy within a subject company. The second and third cases outline the application of the Monte Carlo method in two different environments. These applications made it possible to obtain proof of concept and also to further prove the effectiveness of the Monte Carlo simulation approach.

An effective development of the Monte Carlo approach is proposed and the effectiveness of the method is subsequently evaluated, highlighting the benefits to the host organization and how the approach led to significant improvement in machinery reliability through a bearing replacement strategy.

The design, development and implementation of a bearing replacement strategy provide a simple yet effective approach to achieving significant improvements in system reliability and performance through less downtime and greater cost savings. The paper offers practising maintenance managers and engineers a strategic framework for increasing productive efficiency and output.

The proposed bearing replacement strategy contributes to the existing knowledge base on maintenance systems and subsequently disseminates this information in order to provide impetus, guidance and support towards increasing the development companies in an attempt to move the UK manufacturing sector towards world‐class manufacturing performance.

This paper aims to study the impact of surface texture on grease-lubricated journal bearing, load-carrying capacity, friction and friction coefficient.

The paper opted for a basic application research using the commercial CFD software FLUENT 14.0.

The load-carrying capacity can be enhanced if the surface texture is introduced from a suitable position. The textural shape has a more significant effect on the friction and load-carrying capacity than the friction coefficient. The rheological parameters of grease affect the load-carrying capacity in the same way, i.e. the load increases with the increase in the rheological parameters. With the decrease in the value of cavitation pressure, the cavitation area reduces but the dynamic pressure area gets enlarged.

Because of the chosen research method, the research results may lack the analysis of experiments.

The research results can be applied to the domain in the high-speed spindle and lubricated multibody system.

The investigation on the performances of grease-lubricated journal bearing with surface texture would be significant.

This study aims to investigate the effects of single dent on the film thickness and pressure in elastohydrodynamically lubricated (EHL) point contacts by numerical analysis.

The governing equations of single dent were established and then the variations of the film thickness and pressure induced by the applied load, the entrainment velocity and the ball radius were investigated. Meanwhile, the film thickness and pressure under smooth and dented surfaces were compared with each other.

The dent enhances both the maximum pressure and the second pressure peak. The minimum film thickness arises before the dent under certain conditions. In the meantime, the pressure decreases at the inside of the dent and the film thickness is just the reverse. The entrainment velocity remarkably affects the overall film thickness, whereas the rest of the input parameters mainly decides the details of the film curve. All input parameters remarkably affect the overall pressure, especially the maximum pressure.

This work is helpful to understanding the effect of the single dent on the lubricating properties of EHL point contacts.

The trend of electronic products toward lighter, thinner, and faster transmission is challenging the printed circuit board industry to incorporate high density interconnection technology (such as build‐up and semi‐additive processes). Micro stacked via is one technology utilized to produce high‐density structures. Dielectric resin, conductive paste or via plating are usually applied for the filling process. As compared with other filling methods, via filling plating technology has advantages in offering a shorter process and higher reliability. This paper discusses the influence of different equipment design, operating conditions and additives on via filling plating technology.