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A numerical study of a two‐dimensional turbulent flow in a partially open rectangular cavity such as a room is carried out. The turbulent flow is induced by the energy input due to a localized heat source positioned on the floor of the cavity. This flow is of interest in enclosure fires where the flow in the cavity interacts with the environment through the opening or vents. The focus is on the stable, thermal stratification that arises in the room and on the influence of the opening height. A finite‐difference method is employed for the solution of the problem, using a low Reynolds number k — ε turbulence model for the turbulent flow calculations. This model is particularly suitable for flows in which the possibility for relaminarization exists. It was found that, for high Grashof numbers and for relatively small opening heights, particularly for doorway openings, a strong stable thermal stratification is generated within the cavity, with a cooler, essentially uniform, layer underlying a warmer, linearly stratified, upper layer. As a consequence, turbulence is suppressed and the flow in the upper region of the cavity becomes laminar with turbulence confined to locations such as the fire plume above the source and the shear layer at the opening. The penetration distance and the height of the interface are both found to decrease with a reduction in the opening height. The Nusselt number for heat transfer from the source is seen to be affected to a small extent by the opening height. The basic trends are found to agree with those observed in typical compartment fires. Comparisons with results available in the literature on turbulent buoyancy‐driven enclosure flows indicate good agreement, lending support to this model and the numerical scheme.

Reverses the traditional approach of defining classes or status groups before investigating patterns of social interaction by using patterns of interaction between more basic units such as occupational groups to determine the nature of stratification order. Outlines the theoretical basis and compares this to other methods before giving examples of applications.

The purpose of this paper is to consider the problem of thermal destratification facing engineers and scientists during the motion of fluids which consist of rigid and randomly oriented particles suspended in a viscous medium under the influence of Lorentz force. This paper provides an insight into the non-linear transfer of thermal radiation within the boundary layer.

Similarity transformation and parameterization of the non-linear partial differential equation are carried out. The approximate analytical solution of the governing equation which models the free convective flow of strong and weak concentration of micro-elements in a micropolar fluid over a vertical surface is presented.

It is observed that the velocity and temperature distribution are decreasing properties of thermal stratification parameter S_t. Maximum local skin friction coefficients are ascertained at an epilimnion level (S_t=0) when the magnitude of thermal radiation is small. Thermal stratification parameter has no significant effect on the temperature distribution in the flow near a free stream.

The relationship between stratification of temperature and the transfer of thermal energy during the problem of thermal destratification facing engineers and scientist during the motion of fluids which consist of rigid and randomly oriented particles suspended in a viscous medium under the influence of Lorentz force is unravelled in this paper.

The objective of this work is to investigate the rate of entropy generation of a hybrid nanoliquid (Cu-Ag/Water) flowing on a stretching sheet in the presence of convective boundary conditions, heat generation/absorption, double stratification and Stefan blowing. At present, the capability of interchange of thermal energy is not concerned only with an estimation of the amplification in the rate of heat exchange but also depends on profitable and obliging contemplation. Acknowledging the demands, researchers have been associated with the refinement of the performance of a heat exchange, which is referred to as an intensification of the interchange of heat.

By using a similarity transformation, the system of governing partial differential equations (PDEs) is transformed into the system of nonlinear ordinary differential equations (ODEs). The rebuilt ordinary differential equations are then solved by applying the homotopy analysis method. After computing the temperature, concentration and velocity profiles for a range of relevant study parameters, the resulting results are examined and discussed.

Elevating the Stefan blowing parameter values enhances the temperature profile. Conversely, it diminishes with increasing concentration stratification, thermal stratification and heat generation/absorption coefficient. The rate of entropy generation rises with increasing diffusion parameter, Brinkman number and concentration difference parameter. Stronger viscous forces between the sheet and the fluid flow cause skin friction to increase as fw and Sϕ increase. The local Nusselt number falls as fw and ω rise. However, as Sθ rises, the local Nusselt number gets higher.

The transmission of mass and heat is the basis of the current study, which is useful in a number of industrial and technological domains.

The paper investigates entropy production and heat transmission in a hybrid nanoliquid flow over a stretching sheet, incorporating factors such as heat generation/absorption, convective boundary conditions, Stefan blowing and double stratification. The research highlights a gap in the existing literature, indicating that this specific combination of factors has not been previously explored.

Advocates of market-based reforms in the public sector argue that competition between providers drives up performance. But in the context of schooling, the concern is that any improvements in efficiency may come at the cost of increased stratification of schools along lines of pupil ability and attainments. In this chapter, we discuss our empirical work on competition and parental choice in English primary schools and present a methodology for identifying competition effects that exploits discontinuities in market access close to education district boundaries.

For central banks who study the use of cash, acceptance of card payments is an important factor. Surveys to measure levels of card acceptance and the costs of payments can be complicated and expensive. In this paper, we exploit a novel data set from Hungary to see the effect of stratified random sampling on estimates of payment card acceptance and usage. Using the Online Cashier Registry, a database linking the universe of merchant cash registers in Hungary, we create merchant and transaction level data sets. We compare county (geographic), industry and store size stratifications to simulate the usual stratification criteria for merchant surveys and see the effect on estimates of card acceptance for different sample sizes. Further, we estimate logistic regression models of card acceptance/usage to see how stratification biases estimates of key determinants of card acceptance/usage.

In this chapter, we take up the distinction between applied and general fields of study in order to consider how patterns of gender stratification between them may differ. Purporting to offer industry- and firm-specific skills, applied fields of study are often differentiated from general education pathways that are offered within the university sector. However, as our research demonstrates, there is considerable interplay between these two forms of education when higher education engagement over the life course is examined. Using sequence and cluster analysis, we illustrate five ideal-typical higher education pathways in a sample of males and females over a 22-year period in the Canadian province of British Columbia. The gendered patterns of how individuals choose and move between general and applied fields of study offer a deeper account of stratification within general and applied skill acquisition and provide nuance concerning how vocational education can be conceptualised in relation to the actual higher education pathways students undertake. In Canada, where a high percentage of students gain university-level credentials, vertical and horizontal gender stratification within applied and general fields of study is distinctive and highlights system-specific engagement.

People with intellectual disability die prematurely and from avoidable causes. Innovative solutions and proactive strategies have been limited in addressing this disparity. This paper aims to detail the process of developing a risk stratification tool to identify those individuals who are higher risk of premature mortality.

This study used population health management principles to conceptualise a risk stratification tool for avoidable deaths in people with intellectual disability. A review of the literature examined the existing evidence of causes of death in people with intellectual disability. A qualitative methodology using focused groups of specialist clinicians was used to understand the factors that contributed towards avoidable deaths in people with intellectual disability. Delphi groups were used for consensus on the variables for inclusion in the risk stratification tool (Decision Support Tool for Physical Health).

A pilot of the Decision Support Tool for Physical Health within specialist intellectual disability service demonstrated effective utility and acceptability in clinical practice. The tool has also demonstrated good face and construct validity. A further study is currently being completed to examine concurrent and predictive validity of the tool.

To the best of the authors’ knowledge, this is the only study that has used a systematic approach to designing a risk stratification tool for identifying premature mortality in people with intellectual disability. The Decision Support Tool for Physical Health in clinical practice aims to guide clinical responses and prioritise those identified as at higher risk of avoidable deaths.

Several Flemish social scientists argue for the existence of a dual Flemish labour market as a result of ethnic stratification. Flanders is the Northern, Dutch speaking region of Belgium, which inhabits around six million people. The poor educational level of ethnic minority youngsters is generally considered to be one of the main explaining factors. The purpose of this paper is to find out whether ethnic minority graduates, who have successfully completed their higher education, also face ethnic stratification in the labour market, even though the educational argument does not apply. Therefore, the paper examines differences in labour market positions of the third (Italian) and the second (Turkish and Moroccan) generation immigrants, and a matching Flemish ethnic majority control group.

The study is essentially of a quantitative nature. A postal survey was used to ask recently graduated ethnic minority and majority students from two schools of higher education and one university in Flanders about their career on the labour market after graduation. Universities provide education leading to master diplomas whereas schools of higher education train professional bachelors.

The waiting period between leaving school and entering the labour market is longer for ethnic majority graduates than for ethnic minority graduates. However, once on the labour market the differences in labour market position tend to disappear. Differences in first job wage, contract modalities, labour regime or the executive character of the job were small and non‐significant. Yet 61 per cent of the graduates of Turkish and Moroccan origin feel they have to try harder both in gaining access to the labour market and once in employment.

Further studies will need to confirm these findings, perhaps even with ethnic minorities of other educational levels, in other locations.

The results suggest that closer attention should be paid to the psychological dimension of the school‐to‐work transition of ethnic minority graduates as their psychological contract is under pressure. As they feel their efforts are not sufficiently rewarded – since they feel they have to try harder than others and are rewarded the same – chances are they will reduce their efforts.

The paper focuses on the under‐researched area of ethnic stratification among higher educated graduates. Moreover, it is not limited to factual labour market positions. The inclusion of subjective variables such as opportunity perception and self‐confidence allows additional insight in existing differences and similarities.