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This study aims to explore the formation mechanism of aerodynamic noise of a high-speed maglev train and understand the characteristics of dipole and quadrupole sound sources of the maglev train at different speed levels.

Based on large eddy simulation (LES) method and Kirchhoff–Ffowcs Williams and Hawkings (K-FWH) equations, the characteristics of dipole and quadrupole sound sources of maglev trains at different speed levels were simulated and analyzed by constructing reasonable penetrable integral surface.

The spatial disturbance resulting from the separation of the boundary layer in the streamlined area of the tail car is the source of aerodynamic sound of the maglev train. The dipole sources of the train are mainly distributed around the radio terminals of the head and tail cars of the maglev train, the bottom of the arms of the streamlined parts of the head and tail cars and the nose tip area of the streamlined part of the tail car, and the quadrupole sources are mainly distributed in the wake area. When the train runs at three speed levels of 400, 500 and 600 km·h⁻¹, respectively, the radiated energy of quadrupole source is 62.4%, 63.3% and 71.7%, respectively, which exceeds that of dipole sources.

This study can help understand the aerodynamic noise characteristics generated by the high-speed maglev train and provide a reference for the optimization design of its aerodynamic shape.

The field of broad-based employee ownership within corporations is a specific application of the foundational topic of property ownership. It is situated at the intersection of a broad range of scholarly disciplines including economics, law, finance and management. Each discipline contributes vocabulary and distinctions describing this field. That broad spectrum of disciplinary inquiry is a strength but it also lends a “ships passing in the night” quality to discussions of employee ownership. This paper attempts to unravel the narrative diversity surrounding this topic. Four meanings of ownership are introduced. Those meanings are in turn embedded within two abstract models of the corporation; the corporation as property and the corporation as social institution.

There is no experimental design The paper presents a conceptual overview and introduces a taxonomy of four meanings and two models of ownership.

Four meanings of ownership are introduced. The meanings are ownership as compensation, investment, retirement and membership. Those meanings are in turn embedded within two abstract models of the corporation; the corporation as property and the corporation as social institution.

No hypotheses are advanced. This is not a research paper. A conceptual overview that makes use of taxonomy of meanings and models is introduced to help clarify confusions abundant in the field of employee ownership. Readers may differ with the categories of meanings and models introduced in this conceptual overview.

The ambition of the paper is to describe the various meanings and models of employee ownership presently in use in both academic and applied settings. It is not necessary or desirable to assert the primacy of a single meaning or model in order to achieve progress. The analysis provided here surfaces a range of assumptions about ownership that have heretofore been implicit in both scholarship and in practice. Making those assumptions explicit should prove useful to both scholars and practitioners of employee ownership.

The concept of employee ownership enjoys a relatively broad appeal with the public. Among the academic disciplines that have trained their lights upon it, a more mixed reception prevails. Much of the academic and policy controversy derives from confusion about the nature and structure of employee ownership. This paper attempts to address that confusion by presenting a taxonomy of meanings and models that may prove useful for future research.

This study is one of the first efforts to comprehinsively map the various meanings and models of broad-based employee ownership.

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.

The voice of school principals represents the principals' thoughts and experiences because of their as teachers' evaluator. It provides principals' perception on making sense the teacher evaluation. In qualitative research, voice can provide the truth and meaning of principals' experience in teachers evaluation. Their voices in the qualitative interviews are recorded and transcribed into words (Jackson and Mazzei, 2009 and Charteris and Smardon, 2018). By listening to the voices of principals in five provinces in Indonesia, this study, a qualitative research, intends to explore the principals' sensemaking in teacher evaluation.

This study adopted a qualitative approach, as it was principally concerned with capturing participants' direct experiences in their natural setting as both the teachers' evaluator and school leader (Patton, 2002). The qualitative interview and content analysis were used in this study. The qualitative interview is a type of conversation used to explore informants' experiences and interpretations; in this study, the headmaster (Mishler, 1986; Spradley, 1979 in Hatch, 2002). Researchers used the interviews to uncover the structure of meaning used by principals in making sense the policies that determine teacher evaluations and that are used to carry out evaluations within principal's local authority. The implicit structure can be discovered from direct observation, and the qualitative interviews can bring this meaning to the surface (Hatch, 2002). Therefore, by applying the qualitative interviews, it is expected that information or “unique” interpretations from the principal can be obtained (Stake, 2010). Content analysis is a research technique for making valid conclusions from oral texts into a research context. This analysis can provide new insights, improve researchers' understanding of certain phenomena, or inform other practical actions through the use of verbal data collected in the form of answers to open interview questions (Krippendorff, 2004).

There are three important findings relating to principals' sensemaking of teachers' evaluation; they are teachers' length of service, principals' perceptions of teacher evaluations and consistency in teacher performance improvement. The principals' perception greatly influences their beliefs and sensemaking of teacher evaluation. In essence, teacher evaluation has not been used to identify high-quality teachers. Principals focus more on the improvement of teachers' welfare than teacher actual performance.

Future research should explore principals' attitude toward the stakeholders when student achievement is not in line with the consistent increase in teachers' performance ratings. And, it is also necessary to investigate the policy makers response to see the consistent improvement in teacher's evaluation is not in line with student achievement. Finally, how to eliminate the culture of joint responsibility without causing frictions in the school environment.

The authors hereby declare that this submission is their own work, and to the best of their knowledge, it contains no materials previously published or written by another person, or substantial proportions of material that have been accepted for the award of any other degree or diploma any other publishers.

This study aims to examine how daily communication and transactive memory systems (TMSs) promote implicit team coordination, meaning when team members cooperate smoothly without engaging in explicit communication, in organizations. In TMSs, members share knowledge of who-knows-what with one another.

A survey was conducted with 216 teams consisting of 1,545 people in three organizations. The relationships among daily communication, TMSs and implicit coordination in the survey data and in team performance were analyzed using multi-level structural equation modeling.

Results confirmed a significant influence process model in which “daily communication → TMS → implicit coordination → team performance” at the team level. Therefore, as hypothesized, implicit coordination is positively related to team performance and daily communication has a positive relationship with implicit coordination through mediation by TMSs.

This study demonstrated the evidence of the relation between implicit coordination, TMS, team performance in organizational settings by using multi-level structural equation modeling.

One of the major challenges in the design of thermal equipment is to minimize the entropy production and enhance the thermal dissipation rate for improving energy efficiency of the devices. In several industrial applications, the structure of thermal device is cylindrical shape. In this regard, this paper aims to explore the impact of isothermal cylindrical solid block on nanofluid (Ag – H₂O) convective flow and entropy generation in a cylindrical annular chamber subjected to different thermal conditions. Furthermore, the present study also addresses the structural impact of cylindrical solid block placed at the center of annular domain.

The alternating direction implicit and successive over relaxation techniques are used in the current investigation to solve the coupled partial differential equations. Furthermore, estimation of average Nusselt number and total entropy generation involves integration and is achieved by Simpson and Trapezoidal’s rules, respectively. Mesh independence checks have been carried out to ensure the accuracy of numerical results.

Computations have been performed to analyze the simultaneous multiple influences, such as different thermal conditions, size and aspect ratio of the hot obstacle, Rayleigh number and nanoparticle shape on buoyancy-driven nanoliquid movement, heat dissipation, irreversibility distribution, cup-mixing temperature and performance evaluation criteria in an annular chamber. The computational results reveal that the nanoparticle shape and obstacle size produce conducive situation for increasing system’s thermal efficiency. Furthermore, utilization of nonspherical shaped nanoparticles enhances the heat transfer rate with minimum entropy generation in the enclosure. Also, greater performance evaluation criteria has been noticed for larger obstacle for both uniform and nonuniform heating.

The current numerical investigation can be extended to further explore the thermal performance with different positions of solid obstacle, inclination angles, by applying Lorentz force, internal heat generation and so on numerically or experimentally.

A pioneering numerical investigation on the structural influence of hot solid block on the convective nanofluid flow, energy transport and entropy production in an annular space has been analyzed. The results in the present study are novel, related to various modern industrial applications. These results could be used as a firsthand information for the design engineers to obtain highly efficient thermal systems.

Surface roughness has a serious impact on the fatigue strength, wear resistance and life of mechanical products. Realizing the evolution of surface quality through theoretical modeling takes a lot of effort. To predict the surface roughness of milling processing, this paper aims to construct a neural network based on deep learning and data augmentation.

This study proposes a method consisting of three steps. Firstly, the machine tool multisource data acquisition platform is established, which combines sensor monitoring with machine tool communication to collect processing signals. Secondly, the feature parameters are extracted to reduce the interference and improve the model generalization ability. Thirdly, for different expectations, the parameters of the deep belief network (DBN) model are optimized by the tent-SSA algorithm to achieve more accurate roughness classification and regression prediction.

The adaptive synthetic sampling (ADASYN) algorithm can improve the classification prediction accuracy of DBN from 80.67% to 94.23%. After the DBN parameters were optimized by Tent-SSA, the roughness prediction accuracy was significantly improved. For the classification model, the prediction accuracy is improved by 5.77% based on ADASYN optimization. For regression models, different objective functions can be set according to production requirements, such as root-mean-square error (RMSE) or MaxAE, and the error is reduced by more than 40% compared to the original model.

A roughness prediction model based on multiple monitoring signals is proposed, which reduces the dependence on the acquisition of environmental variables and enhances the model's applicability. Furthermore, with the ADASYN algorithm, the Tent-SSA intelligent optimization algorithm is introduced to optimize the hyperparameters of the DBN model and improve the optimization performance.

The purpose of this paper is to investigate the relationship between preferred choice of school subject and student information behaviour (IB).

Mixed methods were employed. In all, 152 students, teachers and librarians participated in interviews or focus groups. In total, 1,375 students, key stage 3 (11-14 years) to postgraduate, responded to a questionnaire. The research population was drawn from eight schools, two further education colleges and three universities. Insights from the literature review and the qualitative research phase led to a hypothesis which was investigated using the questionnaire: that students studying hard subjects are less likely to engage in deep IB than students studying soft subjects.

Results support the hypothesis that preferences for subjects at school affect choice of university degree. The hypothesis that a preference for hard or soft subjects affects IB is supported by results of an analysis in which like or dislike of maths/ICT is correlated with responses to the survey. Interviewees’ comments led to the proposal that academic subjects can be classified according to whether a subject helps students to acquire a “tool of the Mind” or to apply such a tool. A model suggesting how IB may differ depending on whether intellectual tools are being acquired or applied is proposed.

The “inner logic” of certain subjects and their pedagogies appears closely linked to IB. This should be considered when developing teaching programmes.

The findings offer a new perspective on subject classification and its association with IB, and a new model of the association between IB and tool acquisition or application is proposed, incorporating the perspectives of both teacher and student.

The purpose of this paper is to explore whether official inquiries are an effective method for holding the medical profession to account for failings in the quality and safety of care.

Through a review of the theoretical literature on professions and documentary analysis of key public inquiry documents and reports in the UK National Health Service (NHS) the authors examine how the misconduct of doctors can be understood using the metaphor of professional wrongdoing as a product of bad apples, bad barrels or bad cellars.

The wrongdoing literature tends to present an uncritical assumption of increasing sophistication in analysis, as the focus moves from bad apples (individuals) to bad barrels (organisations) and more latterly to bad cellars (the wider system). This evolution in thinking about wrongdoing is also visible in public inquiries, as analysis and recommendations increasingly tend to emphasise cultural and systematic issues. Yet, while organisational and systemic factors are undoubtedly important, there is a need to keep in sight the role of individuals, for two key reasons. First, there is growing evidence that a small number of doctors may be disproportionately responsible for large numbers of complaints and concerns. Second, there is a risk that the role of individual professionals in drawing attention to wrongdoing is being neglected.

To the best of the authors’ knowledge this is the first theoretical and empirical study specifically exploring the role of NHS inquiries in holding the medical profession to account for failings in professional practice.

This study investigates the relationships between team dynamics and performance in healthcare operations. Specifically, it explores, through wearable sensors, how team coordination mechanisms can influence the likelihood of surgical glitches during routine surgery.

Breast surgeries of a large Italian university hospital were monitored using Sociometric Badges – wearable sensors developed at MIT Media Lab – for collecting objective and systematic measures of individual and group behaviors in real time. Data retrieved were used to analyze team coordination mechanisms, as it evolved in the real settings, and finally to test the research hypotheses.

Findings highlight that a relevant portion of glitches in routine surgery is caused by improper team coordination practices. In particular, results show that the likelihood of glitches decreases when practitioners adopt implicit coordination mechanisms rather than explicit ones. In addition, team cohesion appears to be positively related with the surgical performance.

For the first time, direct, objective and real time measurements of team behaviors have enabled an in-depth evaluation of the team coordination mechanisms in surgery and the impact on surgical glitches. From a methodological perspective, this research also represents an early attempt to investigate coordination behaviors in dynamic and complex operating environments using wearable sensor tools.