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Aims to explore many aspects of the dynamic behaviour of a rotor on bearings, such as the fluid film force. In order to find in an analytical model an effective solution to provide a more readable description of the interaction between journal and bearing.

The present theoretical analysis is carried out to determine the analytical approximate formulation of the fluid film force of porous finite journal bearings. This paper focuses on an approximate mathematical model for the one‐dimensional lubrication equation about the infinitely long porous journal bearing, while the Warner's method is adopted to describe the oil film pressure film in the finite bearing domain.

The proposed model allows a quick analytical determination of the fluid film force for different values of the permeability coefficient, L/D ratio, eccentricity ratio. The results are in good agreement with those achieved by means of the FDM based solution.

The results show good agreement over the typical parameter ranges of the operation on this kind of tribological components.

To identify features of teacher support associated with children who made accelerated progress in writing in an early literacy intervention.

Mixed methods were used to describe the paths, rates, variability, and potential sources of change in the writing development of 24 first grade students who participated in an early literacy intervention for 20 weeks. To describe the breadth and variability of change in children’s writing within a co-constructed setting, two groups who made high and low progress were identified.

We focus on one child, Paul, who made high progress (became more independent in the writing of linguistically complex messages) and the features of teacher support that this child received compared to those who made lower progress. We compare him to another child, Emma, who made low progress. Teacher support associated with high progress included a conversational style and flexibility to adapt to the child’s message intent as the student composed, supporting students to write linguistically more complex and legible messages, and supporting students to orchestrate a broad range of problem-solving behaviors while writing.

We describe how teachers can support children to gradually take control of the composition process, how they can recognize complexity in early written messages and we provide suggestions as to how teachers can systematically assess, observe, and support children’s self-regulation of the writing process.

This paper attempts to interpret the Bartholomew (1973) index of mobility in terms of a directional mobility index based on the one-step expected states of movement corresponding to a specific state of transition matrix. A partial ordering of directional mobility of a general state of transition matrices, referred to as “upward mobility favoring sequential averaging (UMFSA),” is proposed using the algebraic equivalent of the generalized Lorenz ordering of expected states. When the underlying mobility depends on the initial distribution of the states, using a Bayesian approach, the indices are reexamined for a general class of matrices. This enables us to interpret the Prais (1955) and Bibby (1975) mobility index in this framework.

The purpose of this study is to investigate the viscous shear effect on finite porous elastic journal bearings lubricated with non-Newtonian couple stress fluid.

Based on Stokes micro-continuum mechanics, the modified Reynolds equation including bearing deformation was derived. The porous flow was modeled by the complete Darcy–Brinkman equation. To show the viscous shear effects, bearing characteristics including load capacity and friction factor are compared to those obtained from Darcy model with Beavers–Joseph slip conditions (slip flow model [SFM]) by developing a computer program and discussed for different couple stress values, permeabilities and elastic deformation parameters.

It is found that the viscous shearing forces effects of the Brinkman model increase the load capacity and friction factor compared to those derived using SFM. Moreover, the couple stresses increase the load capacity while decreasing the friction factor for both models.

This study introduces for the first time the viscous effect on finite porous elastic journal bearings lubricated with couple stress fluid.

This study aims to investigate the tribological characteristics of a Napier-type second piston ring against a cylinder liner in the presence of graphene nano-additives mixed into 5W40 fully synthetic engine oil.

Wear tests were carried out in the boundary lubrication condition using a reciprocating tribometer, and real engine tests were performed using a single spark ignition Honda GX 270 test engine for a duration of 75 h.

The experimental results of the tribometer tests revealed that the nano-additives formed a layer on the rubbed surfaces of both the piston ring and the cylinder liner. However, this layer was only formed at the top dead center of the cylinder liner during the engine tests. The accumulation of carbon (C) from the graphene was heavily detected on the rubbed surface of piston ring/cylinder liner, mixed with other additive elements such as Ca, Zn, S and P. Overall, the use of graphene nano-additives in engine oil was found to improve the frictional behavior in the boundary and mixed lubrication regimes. Abrasive wear was found to be the main mechanism occurring on the surface of both piston rings and cylinder liners.

Though many researchers have discussed the potential benefits of graphene as a nano-additive in oil to reduce the friction and wear in laboratory tests using tribometers, to date, no actual engine tests have been performed. In this paper, both tribometer and real engine tests were performed on a piston ring and cylinder liner using a fully formulated oil with and without graphene nano-additives in the boundary lubrication condition. It was found that a graphene nano-additive plays an active role in lowering the coefficient of friction and increasing surface protection and lubrication by forming a protective layer on the rubbing surfaces.

The increased regulatory scrutiny in recent years of public corporations, broker‐dealers, and other investment companies has led to a wave of legislative and regulatory reforms. Central to these reforms is the Sarbanes‐Oxley Act (“SOX” or “the Act”), enacted in July 2002. Intended to restore investor confidence in ailing financial markets reeling from a spate of highly publicized corporate governance scandals, the Act reforms the oversight of corporate accounting practices and addresses a wide range of corporate accountability issues. In addition, the Act significantly raises the protections for employees of public companies who report conduct that they reasonably believe constitutes a violation of federal law relating to financial, securities, or shareholder fraud. Thus, the Act creates new federal administrative and judicial remedies for employees who believe they have been retaliated against for blowing the whistle on corporate fraud.

This chapter explores how the creation of multimodal texts using digital technologies, including mobile devices, augmented reality and the World Wide Web can engage, support and reposition primary school-aged literacy learners who have diverse needs. There is emphasis on how the creation of such texts can assist literacy learners in attaining reading comprehension, fluency and motivation.

The purpose of this paper is to study the elastohydrodynamic lubrication point contact problem with bio-based oil as lubricants for an isothermal case. The simulation of the problem is analyzed on smooth and rough asperity.

The modified Reynolds equation is discretized using finite difference and multigrid method with full approximation scheme (FAS), applied for its solution with varying load and speed.

This paper traces out the comparison of minimum and central film thickness with the standard formulation of Hamrock and Dowson. The effect of longitudinal roughness on surfaces is investigated by means of numerical simulations.

The results obtained are comparable with the standard results, and are shown by graphs and tables. Bio-based products bring out an alternative source of lubricant to reduce energy crises.

This study examines employees of Australian firms engaged in sports sponsorship activity. Where the employee is aware of that sponsorship, we consider the ways in which the general beliefs and attitudes of employees towards sponsorship link to their specific attitudes towards the sponsorship activity of their employer and whether these attitudes may influence their behaviour within the organisation. A model linking employees' attitudes towards their employers' sponsorship activity, the creation of favourable attitudes towards working for that employer and behaviours that can benefit the employing organisation is tested and supported. Implications of results include: a stronger focus on using sports sponsorship for internal marketing purposes; involvement of employees in determining the sponsored activity or organisation; and reassessing the overall benefits that derive from sports sponsorship.

This study examined the impact of varying levels of authentic pedagogy on student learning in select 9th and 10th grade history classrooms. The sample included four junior high and four high school teachers. During the initial phase of the study, instructional artifacts (tasks) and classroom observational data were collected and analyzed to determine the level of authentic pedagogy students experienced in their classes. Participating teachers were assigned an authentic pedagogy score based on this analysis that was used as the primary independent variable in subsequent statistical analyses designed to evaluate student learning outcomes. The findings suggest that the use of authentic tasks and instruction has a small, but positive correlation with student performance on the Alabama High School Graduation Exam in use at the time the study was done. A performance benefit was also noted for students who experienced multiple courses at the moderate authentic pedagogy level. The benefit, however, could be attributed to an advanced placement effect since advanced placement students in the sample were more likely to receive moderate authentic pedagogy.