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The problem of laminar natural convection from a vertical circular cone maintained at either a uniform surface temperature or a uniform surface heat flux, and placed in a thermally stratified medium is considered. The governing non‐similarity boundary layer equation for uniform surface temperature are analyzed by using two distinct solution methodologies; namely, (i) a finite difference method and (ii) a local non‐similarity method. For uniform surface heat flux case, the solutions of the governing non‐similarity boundary layer equations are obtained by using three distinct solution methodologies, namely, (i) a finite difference method, (ii) a series solution method and (iii) an asymptotic solution method. The solutions are presented in terms of local skin‐friction and local Nusselt number for different values of Prandtl number and are displayed graphically. Effects of variations in the Prandtl number and stratification parameter on the velocity and temperature profiles are also shown graphically. Solutions obtained by finite difference method are compared with the other methods and found to be in excellent agreement.

The purpose of this article is to explore the difficulties facing entrepreneurs in three groups of women in Israel: immigrant women from the Former Soviet Union (FSU), women belonging to the Palestinian Israeli minority and Jewish Israeli women belonging to the majority population. Relying on the stratification approach, the authors investigate the extent to which labor market, resource and women-specific disadvantages constrain women's entrepreneurship within these three groups.

The target research population consisted of 477 women entrepreneurs who operated businesses between 2009 and 2010. Using systematic sampling, the authors surveyed 148 FSU immigrant women business owners, 150 Jewish Israeli women business owners and 170 Palestinian Israeli women business owners, using a comprehensive questionnaire administered in the entrepreneurs' native language.

The authors found similarities and differences between the three groups as to their ability to handle difficulties deriving from labor market, resource and women-specific disadvantages. Overall, the authors found that Palestinian women entrepreneurs have relatively more difficulties than the other two groups.

Women entrepreneurs' socio-political status within stratified social realities imposes constraints on their economic activities. Further research should investigate policies, which could assist in overcoming these constraints taking into consideration similarities and differences between specific groups.

In addition to shedding light on the impact of socio-political environmental circumstances on women entrepreneurs in a particular country, the authors believe that applying the social stratification approach is especially valuable at the intersection of minority status, gender and entrepreneurship.

The purpose of this paper is to study the influence of thermally stratified medium on a free convection flow from a sphere, which is rotating about the vertical axis, immersed in a stably thermally stratified medium.

An implicit finite‐difference scheme in combination with the quasi‐linearization technique is applied to obtain the steady state non‐similar solutions of the governing boundary layer equations for flow and temperature fields.

The numerical results indicate that the heat transfer rate at the wall decreases significantly with an increasing thermal stratification parameter, but its effect on the skin friction coefficients is rather minimum. In fact, the presence of thermal stratification of the medium influences the heat transfer at wall to be in opposite direction, that is, from fluids to the wall above a certain height. The heat transfer rate increases but the skin frictions decrease with the increase of Prandtl number. In particular, the effect of buoyancy force is much more sensitive for low Prandtl number fluids (Pr = 0.7, air) than that of high Prandtl number fluids (Pr = 7, water). Also the skin friction in rotating direction is less sensitive to the buoyancy force as the buoyancy force acts in the streamwise direction for the present study of thermally stratified medium.

The ambient temperature T_∞∞ is assumed to increase linearly with height $h$. The viscous dissipation term, which is usually small for natural convection flows, has been neglected in the energy equation. The flow is assumed to be axi‐symmetric. The Boussinesq approximation is invoked for the fluid properties to relate density changes to temperature changes, and to couple in this way the temperature field to the flow field.

Free convection in a thermally stratified medium occurs in many environmental processes with temperature stratification, and in industrial applications within a closed chamber with heated walls. Also, free convections associated with heat rejection systems for long‐duration deep ocean powder modules where ocean environment is stratified are examples of such type.

The research presented in this paper investigates the free convection flow on a sphere, which is rotating with a constant angular velocity along its vertical axis in a stably thermally stratified fluid.

The purpose of this study is to focus on changes in stratification structures in a rural community of the Punjab, Pakistan. The village was previously studied by Eglar suggesting strong caste structure. Keeping her study as a base, the authors attempt to measure structural changes that have occurred from the 1960s through 2008.

Data were drawn from a probability sample survey which was conducted in the village. Systematic sampling technique was used for selection of the respondents. An interview schedule was developed to obtain information from persons, age 55+ years. The older age group was expected to have observed changes over the period of time.

The findings are based on trend and regression analyses. Source of income is an indicator of shift from caste to class structure. The results show that stratification structure of the village has changed since 1960. Changes in traditional stratification structure emerged in the 1970s and became prominent in the 1990s and onwards. These changes occurred mainly due to economic factors, international migration and education. It is found that the class system has partially replaced the caste based stratification in the village.

Public policies can be designed to promote or resist the changes that have occurred due to the identified causal factors.

The present study is expected to throw light on factors which gave rise to the emergence of the class system in rural areas of Pakistan.

The purposes of this research are to study the theory and method of multi-attribute index system design and establish a set of systematic, standardized, scientific index systems for the design optimization and inspection process. The research may form the basis for a rational, comprehensive evaluation and provide the most effective way of improving the quality of management decision-making. It is of practical significance to improve the rationality and reliability of the index system and provide standardized, scientific reference standards and theoretical guidance for the design and construction of the index system.

Using modern methods such as complex networks and machine learning, a system for the quality diagnosis of index data and the classification and stratification of index systems is designed. This guarantees the quality of the index data, realizes the scientific classification and stratification of the index system, reduces the subjectivity and randomness of the design of the index system, enhances its objectivity and rationality and lays a solid foundation for the optimal design of the index system.

Based on the ideas of statistics, system theory, machine learning and data mining, the focus in the present research is on “data quality diagnosis” and “index classification and stratification” and clarifying the classification standards and data quality characteristics of index data; a data-quality diagnosis system of “data review – data cleaning – data conversion – data inspection” is established. Using a decision tree, explanatory structural model, cluster analysis, K-means clustering and other methods, classification and hierarchical method system of indicators is designed to reduce the redundancy of indicator data and improve the quality of the data used. Finally, the scientific and standardized classification and hierarchical design of the index system can be realized.

The innovative contributions and research value of the paper are reflected in three aspects. First, a method system for index data quality diagnosis is designed, and multi-source data fusion technology is adopted to ensure the quality of multi-source, heterogeneous and mixed-frequency data of the index system. The second is to design a systematic quality-inspection process for missing data based on the systematic thinking of the whole and the individual. Aiming at the accuracy, reliability, and feasibility of the patched data, a quality-inspection method of patched data based on inversion thought and a unified representation method of data fusion based on a tensor model are proposed. The third is to use the modern method of unsupervised learning to classify and stratify the index system, which reduces the subjectivity and randomness of the design of the index system and enhances its objectivity and rationality.

The increased income and modernity have greatly impacted Chinese consumers’ attitudes and purchasing behavior, making them more sophisticated than ever before. The purpose of this paper is to examine the interrelationship among social stratification, materialism, post-materialism, and consumption values contributing uniquely to understanding Chinese consumers in the context of drastic economic and social changes.

Survey method was used to test the proposed model and answer the research questions. The data were collected in Shanghai, the largest city on the eastern coast of China. A multi-stage random sampling strategy was employed to acquire a representative sample of the population in the city. A total of 2,910 completed questionnaires were used for data analysis.

The results show that objective social status has a negative effect on post-materialism, whereas subjective social status has a positive effect. Social status does not seem to have a significant effect on materialism. Post-materialism also has a strong positive effect on the consumption orientations of emotional value and social value.

China was chosen as the research context in this study. As a booming emerging market, China provides an intriguing platform to examine social stratification and materialism. At the macro level, China is developing a new social structure due to the drastic social and economic changes. At the individual consumer level, as China moves further into a market-oriented economy, traditional Chinese values have changed rapidly. Western consumption values and phenomena such as overspending and conspicuous consumption have begun to take hold in China, especially among young people. It is critical for business managers to understand the shift of consumption values among Chinese in order to successfully capture this market.

A cursory review of past literature reveals that researchers have examined materialism primarily along two avenues: one puts materialism within a macro framework involving political interest or civic engagement (e.g. Davis et al., 1999; Inglehart, 1990); the other one takes a micro perspective exploring the impact of materialism on consumer attitudes and behavior (e.g. Park and Rabolt, 2009; Xiao and Kim, 2009). However, little research has been conducted linking the two approaches. The present study intends to examine the interrelationship among social stratification, materialism, post-materialism, and consumption values. Hopefully, it will shed some light on the connection between macro environment and micro consumer behavior. Furthermore, the current research provides evidences for the emerging transformation to a post-materialistic marketplace.

Resultant leading equations are formed with non-linear partial differential equations by adopting a low Reynolds theory approximation. For a better and easier understanding of the role of physical features of the main problem, the equations are reduced to non-dimensional ordinary differential equations by incorporating the locally similar and non-similar dimensionless variables. In light of practical importance, all the significant findings are approximated by solving the equations with the assistance of a modified bvp4c built-in package. The effective speed, temperature and volume fraction of the same materials are displayed to address the behaviors of different controlling influences.

This work is inaugurated to investigate thermal cycling, thermal striping and thermal stratification, which cause thermally induced damage during the wavy confined flow domains. Such physical constraints are imposed on the wavy surface while considering the wavy dynamics of shear thinning materials. The impact of gravity is assumed on the vertical wavy surface, which is observed as the main source for the wavy flow occurrence. The surface’s amplitude plays a critical role in generating a high temperature difference. The same phenomenon is further extended with the applications of thermal radiation, mixed convection and dynamical homogeneous/heterogeneous reactions.

For instance, the higher stratification factor causes a reduction in the liquid wavy speed and temperature, and the rising chemically reactive rate factor declines the volume fraction during the typical wavy motion of the materials. Moreover, the larger amplitude and mixed convective factor reduced and uplifted the speed of the materials, respectively. The surface resistive forces are monitored with the graphical visualization of local similar skin friction and are determined larger by varying the Weissenberg and mixed convective factors. The affective liquid speed, temperature and volume fraction are plotted to address the behaviors of different controlling factors. These impacts are listed, i.e. with higher stratification factors, a reduction is noticed in the liquid velocity and temperature. On the other hand, an opposite depict is noticed for higher heat generation factors. The reduction in volume fraction is reported with variation in the reaction factor and Schmidt number.

After carefully assessing the previously referenced work, it is evident that the literature has yet to incorporate thermally stratified Williamson fluid. Meanwhile, the motion of the materials is noticed due to the gravitationally affected wavy surface. Such physical phenomenon is further approximated by testing a dynamical reaction during its motion. An effective presentation of all the outcomes is portrayed via graphs and approximated numerical results.

According to the Colombian Labour Ministry, in 2015, 750,000 persons officially worked as household employees. Ninety-eight per cent of these employees are women who tend to live in Bogotá’s (southern) urban fringe and travel to the city’s wealthier north on a daily basis. Yet public transportation in the Colombian capital is subject to stratification. Besides overcrowding and delays, petty crime and sexual harassment, fringe areas remain underserved. Based on ethnographic data, in this chapter, the authors discuss findings from a 3-year research project on female household employees’ subjective experience of space. Specifically, the authors explore their capacity (motility) to be mobile. This perspective breaks with the limits of bounded categories such as ‘urban’, ‘neighbourhood’ or ‘class’, to highlight their situational and spatial mutability. Moreover, an investigation of motility includes people’s potential to move as well as their subjective experiences of mobility. The research shows how gender intersects with local labour regimes and infrastructure to negatively affect women’s mobility. Urban stratification is not only a question of locale of residence and access to services, but importantly (re)produced in the household employees’ subjective experience of their daily commute, which they describe as suffering. In their limited spare time, female household employees abstain from travelling, effectively curbing their active appropriation of urban space. The research thus illuminates how spatial, social and economic dimensions mutually interact to impact on the women’s lives and possibilities.

We examine sample characteristics and elicited survey measures of two studies, the Health and Retirement Study (HRS), where interviews are done either in person or by phone, and the Understanding America Study (UAS), where surveys are completed online and a replica of the HRS core questionnaire is administered. By considering variables in various domains, our investigation provides a comprehensive assessment of how Internet data collection compares to more traditional interview modes. We document clear demographic differences between the UAS and HRS samples in terms of age and education. Yet, sample weights correct for these discrepancies and allow one to satisfactorily match population benchmarks as far as key socio- demographic variables are concerned. Comparison of a variety of survey outcomes with population targets shows a strikingly good fit for both the HRS and the UAS. Outcome distributions in the HRS are only marginally closer to population targets than outcome distributions in the UAS. These patterns arise regardless of which variables are used to construct post-stratification weights in the UAS, confirming the robustness of these results. We find little evidence of mode effects when comparing the subjective measures of self-reported health and life satisfaction across interview modes. Specifically, we do not observe very clear primacy or recency effects for either health or life satisfaction. We do observe a significant social desirability effect, driven by the presence of an interviewer, as far as life satisfaction is concerned. By and large, our results suggest that Internet surveys can match high-quality traditional surveys.