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In response to the problem of insufficient traction/braking adhesion force caused by the existence of the third-body medium on the rail surface, this study aims to analyze the utilization of wheel-rail adhesion coefficient under different medium conditions and propose relevant measures for reasonable and optimized utilization of adhesion to ensure the traction/braking performance and operation safety of trains.

Based on the PLS-160 wheel-rail adhesion simulation test rig, the study investigates the variation patterns of maximum utilized adhesion characteristics on the rail surface under different conditions of small creepage and large slip. Through statistical analysis of multiple sets of experimental data, the statistical distribution patterns of maximum utilized adhesion on the rail surface are obtained, and a method for analyzing wheel-rail adhesion redundancy based on normal distribution is proposed. The study analyzes the utilization of traction/braking adhesion, as well as adhesion redundancy, for different medium under small creepage and large slip conditions. Based on these findings, relevant measures for the reasonable and optimized utilization of adhesion are derived.

When the third-body medium exists on the rail surface, the train should adopt the low-level service braking to avoid the braking skidding by extending the braking distance. Compared with the current adhesion control strategy of small creepage, adopting appropriate strategies to control the train’s adhesion coefficient near the second peak point of the adhesion coefficient-slip ratio curve in large slip can effectively improve the traction/braking adhesion redundancy and the upper limit of adhesion utilization, thereby ensuring the traction/braking performance and operation safety of the train.

Most existing studies focus on the wheel-rail adhesion coefficient values and variation patterns under different medium conditions, without considering whether the rail surface with different medium can provide sufficient traction/braking utilized adhesion coefficient for the train. Therefore, there is a risk of traction overspeeding/braking skidding. This study analyzes whether the rail surface with different medium can provide sufficient traction/braking utilized adhesion coefficient for the train and whether there is redundancy. Based on these findings, relevant measures for the reasonable and optimized utilization of adhesion are derived to further ensure operation safety of the train.

The purpose of this paper is to show that the droplet impact phenomenon is important for the advancement of industrial technologies in many fields such as spray cooling and ink jet printing. Droplet bouncing on the nonwetting surfaces is a special phenomenon in the impact process which has attracted lots of attention.

In this work, the authors fabricated two kinds of representative nonwetting surfaces including superhydrophobic surfaces (SHS) and a slippery liquid-infused porous surface (SLIPS) with advanced UV laser processing.

The droplet bouncing behavior on the two kinds of nonwetting surfaces were compared in the experiments. The results indicate that the increasing Weber number enlarges the maximum droplet spreading diameter and raises the droplet bounce height but has no effect on contact time.

In addition, the authors find that the topological SHS and SLIPS with the laser-processed microwedge groove array produce asymmetric droplet bouncing with opposite offset direction. Microdroplets can be continuously transported without any additional driving force on such a topological SLIPS. The promising method for manipulating droplets has potential applications for the droplet-based microfluidic platforms.

This paper studies the lateral stability regulation of intelligent electric vehicle (EV) based on model predictive control (MPC) algorithm.

Firstly, the bicycle model is adopted in the system modelling process. To improve the accuracy, the lateral stiffness of front and rear tire is estimated using the real-time yaw rate acceleration and lateral acceleration of the vehicle based on the vehicle dynamics. Then the constraint of input and output in the model predictive controller is designed. Soft constraints on the lateral speed of the vehicle are designed to guarantee the solved persistent feasibility and enforce the vehicle’s sideslip angle within a safety range.

The simulation results show that the proposed lateral stability controller based on the MPC algorithm can improve the handling and stability performance of the vehicle under complex working conditions.

The MPC schema and the objective function are established. The integrated active front steering/direct yaw moments control strategy is simultaneously adopted in the model. The vehicle’s sideslip angle is chosen as the constraint and is controlled in stable range. The online estimation of tire stiffness is performed. The vehicle’s lateral acceleration and the yaw rate acceleration are modelled into the two-degree-of-freedom equation to solve the tire cornering stiffness in real time. This can ensure the accuracy of model.

The supercritical design of tail rotor drive shaft has attracted more attention in helicopter design due to its high power–weight ratio and low maintenance cost. However, there exists excessive vibration when the shaft passes through the critical frequency. Dry friction damper is the equipment applied to the drive shaft to suppress the excessive vibration. In order to figure out the damping mechanism of the dry friction damper and improve the damping efficiency, the dynamic model of the shaft/damper system is established based on the Jeffcott rotor model.

The typical frequency response of the system is studied through bifurcation diagrams, amplitude-frequency characteristic curves and waterfall frequency response spectrum. The typical transient responses under frequency sweeps are also obtained.

The results show that the response of the system changes from periodic no-rub motion to quasi-periodic rub-impact motion, and then to synchronous full annular rub-impact, and finally, back to periodic no-rub motion. The slip of the rub-impact ring improves the stability of the system. Besides, the effects of the system parameters including critical dry friction force, rub-impact friction coefficient, initial clearance on the stability and the vibration damping capacity are studied. It is observed that the stability changes significantly varying the three parameters respectively. The vibration damping capacity is mainly affected by the critical dry friction force and the initial clearance.

Presented results provide guidance for the design of the dry friction damper.

The purpose of this study is twofold: to determine if implementing a global citizenship education curriculum can aid the development of Emirati students’ social responsibility competence and to experiment with different instructional strategies that aim to yield improvement in the social responsibility of students.

The intervention research study used a mixed-methods quasi-experimental approach to examine Emirati students’ social responsibility gains and overall perceptions of a global citizenship education curriculum. Conceptual frameworks for instructional design of service-learning were used as theoretical underpinnings. The data were collected from student reflections, field notes, questionnaires and interviews.

Both the quantitative and qualitative data indicated that the global citizenship curriculum advanced students' understanding of social responsibility and civic concepts, specifically civic awareness, social justice and diversity.

For future studies, researchers are encouraged to expand the current study's five-week timeframe by exploring the implications of a global citizenship education curriculum over a full term or even a whole academic year.

The results of the present study indicate that educators should experiment with curriculum redesign to further facilitate the development of social responsibility in undergraduate students. The results also suggest that educators incorporate specific instructional strategies such as integrated reflections and intergroup dialogue on social issues.

Social responsibility and global citizenship education have broadly been based on Western paradigms. Few studies have explored the impact of global citizenship education on the development of students' social responsibility in the Gulf region. This study fills the gap in knowledge by lending evidence of the role of global citizenship education in undergraduate university programs in the Gulf.

The purpose of the study is to create substantial awareness for safety precautions and safety parameters to lessen occupational injuries and accidents. Utilization of safety culture phenomenon with its fundamental understanding has imperative consideration for safety compliance and participation behaviors. Thoughtful aim of this study is the extension of knowledge related to safety orientation particularly in primary health-care workforce.

Only slips and trips accounted for 40% of workplace injuries in nursing professionals. To identity, the data were collected through structured surveys from nursing professionals of public and private hospitals in Pakistan. To evaluate that data for current study, standardized regression coefficients (parameter estimation) with 95% confidence interval and 5,000 bootstrap samples were subjected. Confirmatory factor analysis was also used to measure the validity of study constructs.

The potential findings of present study have assured the presence of safety culture at workplace has potential to influences negative safety outcomes. In addition, safety compliance and safety participation as mediation paths would be the strengthening addition to safety model. These findings have extended the existing understanding of compliance and participation behaviors from single factor to two different constructs of safety orientation. This safety culture model offers an evidence-based approach to nursing practitioners and nursing managers with implications for nurse’s safety, education and training.

Occupational injuries and accidental happenings have adversely affecting the quality of care, patient’s recovery spam, satisfaction level and psychological health in care agents. This study has proposed a comprehensive model for understanding the mechanism of possible and reliable safety implications at health-care units. Prior knowledge has limitation to the inevitable effects of occupational injuries only rather than focusing on corrective actions against this phenomenon.

The purpose of this study is to explore the expectations and experiences regarding a robotic shower, from a dual user perspective.

This was an explorative qualitative study in which elderly and personnel were interviewed before the robotic shower was installed and again after four or five months of usage.

The elderly participants found the robotic shower empowering. The personnel’s experiences encompassed their own work conditions, as well as the user value for the elderly. A shared experience for both user groups was a more independent shower situation for the elderly.

Low user frequency among the elderly may have affected the results; more frequent use may lead to different user experiences. Understanding whether and to what extent long-term use affects user experience is important for future adoption and implementation.

Implementation of digital assistive technology (DAT) should focus on the user value of the DAT for all possible user groups, as the different users may experience different values over time. In addition, approaching adoption and acceptance issues of DAT from a learned helplessness perspective may help users find value in the DAT and the independence these aim to provide, helping users maintain or increase quality of life.

This study presents a dual user experience of a DAT in an intimate care situation and shows the importance of including both elderly and personnel to fully understand the value of DATs.

Nowadays in the competitive economy, the field of entrepreneurship and particularly female entrepreneurship is rapidly advancing, and its contribution to the economy is imperative. Consequently, the female business students’ factors and university support factors are imperative to nurture the entrepreneurial intentions, but the literature does not address them at large. Therefore, this study aims to examine the impact of proactive personality, entrepreneurial self-efficacy and perceived university support factors on female student’s entrepreneurial intentions.

The data from a total of 306 female students from the business schools of universities of Pakistan is collected through the personal physical-survey questionnaires. The data were then analyzed through Partial Least Square-Structural Equation Modelling (PLS-SEM) technique for results.

The results indicate that the proactive personality, entrepreneurial self-efficacy and university support factors are the significant predictors of entrepreneurial intentions of female students. Moreover, the results also support that entrepreneurial self-efficacy partially mediates the relationship between proactive personality and entrepreneurial intentions of female students.

To the best of authors’ knowledge, the study originality lies in the testing of university support factors and individual personality factors (entrepreneurial self-efficacy and proactive personality) as the predictors of entrepreneurial intentions. Moreover, the present study provides the useful insight for the policymakers in formulating, delivering and evaluating educational policies into the universities for female students.

The purpose of the current flow configurations is to bring to attention the thermophysical aspects of magnetohydrodynamics (MHD) Williamson nanofluid flow under the effects of Joule heating, nonlinear thermal radiation, variable thermal coefficient and activation energy past a rotating stretchable surface.

A mathematical model is examined to study the heat and mass transport analysis of steady MHD Williamson fluid flow past a rotating stretchable surface. Impact of activation energy with newly introduced variable diffusion coefficient at the mass equation is considered. The transport phenomenon is modeled by using highly nonlinear PDEs which are then reduced into dimensionless form by using similarity transformation. The resulting equations are then solved with the aid of fifth-order Fehlberg method.

The rotating fluid, heat and mass transport effects are analyzed for different values of parameters on velocity, energy and diffusion distributions. Parameters like the rotation parameter, Hartmann number and Weissenberg number control the flow field. In addition, the solar radiation, Joule heating, Prandtl number, thermal conductivity, concentration diffusion coefficient and activation energy control the temperature and concentration profiles inside the stretching surface. It can be analyzed that for higher values of thermal conductivity, Eckret number and solar radiation parameter the temperature profile increases, whereas opposite behavior is noticed for Prandtl number. Moreover, for increasing values of temperature difference parameter and thermal diffusion coefficient, the concentration profile shows reducing behavior.

This paper is useful for researchers working in mathematical and theoretical physics. Moreover, numerical results are very useful in industry and daily-use processes.