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An attempt is made to study magnetohydrodynamic viscous fluid impinging orthogonally toward a stagnation point on a vertical surface lubricated with power law fluid. It has been assumed that the surface temperature varies linearly with the distance from the stagnation point. The problem is governed by system of partial differential equations for both the base fluid and the lubricant. The continuity of velocity and shear stress is assumed at the interface layer between the base fluid and the lubricant. Dimensionless variables are introduced to transform original problem into ordinary differential equations. An implicit finite-difference scheme known as the Keller-Box method is implemented to obtain the numerical solutions. The influence of various important parameters is presented in the form of graphs and tables. The limiting cases for full and no-slip conditions are deduced from the present solutions. A comparison of the present results with the existing results in the special case validates the obtained numerical solutions. The purpose of this study is to see the behaviour of flow characteristics in the presence of lubrication.

The authors’ problem is governed by system of partial differential equations for both the base fluid and the lubricant. Dimensionless variables are introduced to transform original problem into ordinary differential equations. The obtained ordinary differential equation along with boundary conditions are highly nonlinear and coupled. An implicit finite-difference scheme known as the Keller-Box method is implemented to obtain the numerical solutions.

Some findings of this study are that the lubricant increases the velocity of the base fluid inside the boundary layer. In the case of full slip, the effects of viscosity are suppressed by the lubricant. The temperature of the base fluid decreases by increase in lubrication on the surface. By increasing the slip on the surface, the skin friction decreases and local Nusselt number increases, but the rate of increase or decrease is less in magnitude for the case of opposing flow. The similarity solutions only exist for n = 1/2. A non-similar solution is obtained for the other values of the power-law index n.

The study of flow phenomenon over a lubricated surface has important applications in machinery components such as fluid bearings and mechanical seals. Coating is another major application of lubrication including the preparation of thin films, printing, painting, etc. The authors hope that the current study will provide the roadmap for the future studies in this direction.

The main purpose of this study is to examine the effects of moving wall on the mixed convection flow and heat transfer in a right-angle triangular cavity filled with a micropolar fluid.

It is assumed that the bottom wall is uniformly heated and the right inclined wall is cold, whereas the vertical wall is adiabatic and moving with upward/downward velocity v₀/−v₀, respectively. The micropolar fluid is considered to satisfy the Boussinesq approximation. The governing equations and boundary conditions are solved using the Galerkin finite element method. The Penalty method is used to eliminate the pressure term from the momentum equations. To accomplish the consistent solution, the value of the penalty parameter is taken 10⁷. The simulations are performed for a wide range of Richardson number, micropolar parameter, Prandtl number and Reynolds number.

The results are presented in the form of streamlines, isotherms and variations of average Nusselt number and fluid flow rate depending on the Richardson number, Prandtl number, micropolar parameter and direction of the moving wall. The flow field and temperature distribution in the cavity are affected by these parameters. An average Nusselt number into the cavity in both cases increase with increasing Prandtl and Richardson numbers and decreases with increasing micropolar parameter, and it has a maximum value when the lid is moving in the downward direction for all the physical parameters.

The present investigation is conducted for the steady, two-dimensional mixed convective flow in a right-angle triangular cavity filled with micropolar fluid. An extension of the present study with the effects of cavity inclination, square cavity, rectangular, trapezoidal and wavy cavity will be the interest of future work.

This work studies the effects of moving wall, micropolar parameter, Richardson number, Prandtl number and Reynolds number parameter in a right-angle triangular cavity filled with a micropolar fluid on the fluid flow and heat transfer. This study might be useful to flows of biological fluids in thin vessels, polymeric suspensions, liquid crystals, slurries, colloidal suspensions, exotic lubricants, solar engineering for construction of triangular solar collector, construction of thermal insulation structure and geophysical fluid mechanics, etc.

The purpose of this paper is to analyze numerical results for heat transfer through mixed convection in an incompressible steady lid-driven fluid flow inside a trapezoidal cavity in the presence of a uniform magnetic field.

In this study, the authors have considered three different cases, in which left and right walls of the cavity are tilted at different angles of 0, 30 and 45 degrees, respectively. Both left and right side walls of the cavity are taken cold and the upper wall is insulated and assumed moving with constant speed, whereas the bottom wall is considered to be heated uniformly/non-uniformly. To eliminate pressure term, penalty method is applied to governing Navier–Stokes’ equations. The reduced equations are solved by Galerkin weighted residual technique of finite element method. Grid-independent results are obtained and shown in terms of plots for streamlines, isotherms, Nusselt number and average Nusselt number for a wide range of flow parameters, including Rayleigh numbers Ra, Prandtl number Pr and Hartman number Ha.

It has been observed that the effects of moving lid become negligible for Ra = 100,000, whereas increasing Rayleigh number results in stronger streamline circulation and convection dominant effects inside the enclosure. Local Nusselt number Nu along the bottom wall is observed to be maximum at edges and it reduces while moving toward the center from edges, and attains minimum value at the center of the bottom wall.

The problem is modeled for laminar and incompressible flow, induced magnetic field has been considered negligibly small and local thermal equilibrium has been assumed.

In this investigation, the authors have presented new and original results for mixed convection flow inside a lid-driven trapezoidal cavity under the influence of a magnetic field. Hence, this study would be important for the researchers working in the area of heat transfer in cavity flows involving magnetic effects to become familiar with the flow behavior and properties.

The purpose of this paper is to perform a numerical study for heat transfer through natural convection in the presence of a constant magnetic field in an incompressible steady nanofluid flow inside an isosceles triangular cavity.

For this flow problem, the left wall of the cavity subjected to uniform/nonuniform heat was considered, while right and bottom walls of the cavity were kept cold. The obtained equations were solved by using the Galerkin weighted residual technique. Results are computed for a wide range of parameters including Rayleigh number (Ra) (10^3 < Ra < 10^7), Hartman number (Ha) (0 < Ha < 60), and heat-generation/-absorption coefficient (q) (−10 < q < 10), while, Prandtl number (Pr) was kept fixed at 6.2. These computed results are presented in terms of stream functions, isotherms, Nusselt numbers and average Nusselt numbers through figures.

It is observed that, in case of uniform heating of the side wall, the strength of stream lines’ circulations increases with an increase in Ra and decreases with an increase in Ha. Similarly, by increasing heat-absorption coefficient q, an increase in the circulation strength is noted and the circulation cell moves towards the left wall in the presence of a heat sink (q < 0) and moves to the cold right wall in the presence of a heat source (q > 0). In the case of nonuniformly heated left wall in the presence of a heat source (q > 0), a higher-temperature gradient is observed in the cavity and isotherms are clustered to the left wall in the lower portion and to right wall in the upper portion; these appear to be straight and parallel to the x-axis near the bottom wall. On the other hand, the heat transfer rate along all the walls of the cavity is observed to be higher for smaller values of q. Whereas, Nusselt number along the bottom wall (Nu-B) increases with an increase in the values of x, while, that along the left wall (Nu-L) first increases and then decreases. But Nusselt number along the right wall (Nu-R) is found to be qualitatively opposite to Nu-L with an increase in distance x. Whereas, average Nusselt number increases with an increase in Rayleigh number Ra and heat-generation/-absorption coefficient q.

The problem is formulated for an incompressible flow; viscous dissipation has been neglected, negligible induced magnetic field has been considered and local thermal equilibrium has been considered.

Results presented in this paper are original and new for the effects of a uniform magnetic field on the natural convection of Cu–water nanofluid in a triangular cavity. Hence, this study is important for researchers working in the area of heat transfer in cavity flows involving the nanofluid to become familiar with the flow behavior and properties.

The purpose of this paper is to estimate the short and the long run wheat demand elasticities in Pakistan.

Using cointegration and vector error correction model (VECM) techniques, the main objective of the study has been achieved.

The estimated long run and the short run elasticities suggest that income is the most significant determinant of wheat consumption in the long run while price of wheat is the major affecting factor of wheat consumption only in the short run.

The estimated demand elasticites may be used for framing any future food security policy in Pakistan. The less elastic nature of wheat demand both in the short and the long run suggests that under the likely Doha Round agricultural trade liberalization, wheat price rise will harm the poor consumers.

Wheat demand elasticities are estimated within the framework of cointegration and VECM to differentiate short run and long run elasticities in Pakistan.

This classroom-based qualitative study explored the effectiveness of the debate learning strategy in female postgraduate education in Saudi Arabia, which is implementing its recent national development plan, Vision 2030. Educational reform is key to its transition to a modernized, knowledge-based economy. The debate format was used to elicit views on educational reforms and necessitated forming and articulating well-reasoned arguments and logic.

At a Saudi Eastern Province university, 13 female postgraduate students (preservice teachers) participated in a student-centered learning environment conducive to debates. Documents prepared for the debate underwent a qualitative content analysis.

Data were readily classified into five categories: educational reforms should meet 21st century skills, achieve educational outcomes, ensure Saudi Arabia’s knowledge-based economy, prioritize the role of the university and recognize the impact of both teachers and curricula. As key players in the nation’s future, participants affirmed the ongoing need for educational innovation and modernization.

While debates are an authentic part of Arabian heritage, they are less utilized in Saudi higher education settings. Findings affirm that debates are a beneficial learning strategy for bolstering future educators’ participation in Saudi Arabia’s educational reform.

The mammoth proportions of Public Expenditure, its accountability, its control, must be one of the biggest problems any government has had to meet. Despite all its counselling to the public spenders, its massive efforts to scale down the spending, there is extremely little to show for it. The Departments and State Services have become so large, they have outgrown government control; they are in fact forms of government in themselves. When a body established with a definite role becomes so big and powerful, as many of the authorities in the country have become, they tend to resent any form of control over them. History has many such examples in one form or another. Where an ocean divides them, the subordinate power may seek a separate nationhood for itself, as the American colonies did a couple of centuries or more ago. They chose the right moment to rebel when the home government sought to pass on extra levy on the importation of tea, which the Colonists turned into a slogan “no taxation without representation”. The truth, however, was they had outgrown the mother country and saw themselves as a new nation in a new land immensely rich in natural resources, riches all theirs for the taking. Much of the old country understood their aspirations and in the final settlement, the British were more than generous to them.

The post-pandemic era has shifted most industries, businesses and consumers online, increasing the demand for electronic devices, mainly laptops. Additionally, most non-Western countries inhabit highly religious but cash-strapped individuals, making them a potential market for second-hand laptops. With this in mind, this study aims to explore the effects of lenient return policy (LRP) and religiosity on consumer confidence in retailer (CCR), consumer well-being and purchase intention.

This paper conducted a between-subjects field experiment comparing two return policy conditions (cash return vs. other return) with a sample of 222 participants. Data were analysed using partial least squares structural equation modelling (PLS-SEM) to test the hypothesised relationships, and multigroup analysis (MGA) was employed to assess the experimental effects based on the return policy conditions. The moderating effects of religiosity were also examined. All analyses were conducted using SmartPLS software.

The results confirm that an LRP positively predicts consumer confidence in retailer, well-being and purchase intention. Religiosity had a moderating effect on LRP outcomes. Additionally, the experiment confirmed that consumers experienced better well-being and were more likely to purchase if offered full cashback.

Retailers of second-hand shopping products should offer LRP (full cashback) to foster consumer confidence, well-being and purchase intention. Additionally, for highly religious consumers, aligning return policies with religious principles should further enhance consumer well-being and purchase intention.

This study is among the earliest to investigate the impact of LRP on CCR and well-being. Moreover, a novel attempt is made to explore the moderating effects of religiosity on LRP outcomes. Likewise, a field experiment to validate the greater effects of cashback on consumer well-being and purchase intention adds to the novelty of this study.

This research study investigates the factors that influence e-customer satisfaction, e-trust, perceived value and consumers repurchase intention in the context of the B2C e-commerce segment. It investigates the mediation effect of e-customer satisfaction, e-trust and perceived value on repurchase intention. It also examines the moderating role of prior online experience.

Based on the adapted questionnaire, pre-recruited enumerators collected the data from five leading business universities of Karachi. They distributed 425 questionnaires and received 415 questionnaires. The study has used Partial Least Square-Structure Equation Modeling (PLS-SEM) technique for data analysis.

We have tested 20 hypotheses, of which our results do not support five, including two direct, two mediating. Our results support all the direct hypotheses except the following two: (1) delivery service affects e-satisfaction (2) customer services quality effect on trust. We did not find support for the following two mediating hypotheses (1) e-satisfaction mediates delivery services and repurchase intention, (2) service quality mediates customers' service quality and repurchase intention. Our results do not support one moderating relationship. Prior online experience moderates e-perceived value and repurchase intention.

This research provides valuable information to the online retailers of B2C e-commerce, which can help them make strategies based on their consumers' behavior and encourage them to make repeat purchases from online retailing stores. It allows future researchers to replicate the model in cross-cultural studies in different product categories.

We have examined the moderating effect of prior online experience between (e-satisfaction, e-trust and perceived value) on the repurchase intention.

This study aims to check the impact of consumer ethnocentrism (CE) and animosity on brand image (BI) and brand loyalty (BL) of Indian made cosmetic products in Pakistan and to check the mediation role of product judgment (PJ) related to Indian made cosmetic products in this relationship.

In this study, the researcher used quantitative techniques to collect data. Online survey strategy was used for data collection and the technique of purposive sampling was used to select 280 consumers as respondents of said study. SPSS-20 and AMOS-21 were used for data analysis and to test the hypotheses of the study.

The results indicate that there is a positive relationship between CE and BL that is the novel result of this study because past studies proved negative relation in CE and BL and there is no direct relationship between CE and BI. The results also indicate that consumer animosity (CA) has a negative impact on BI and BL of Indian made cosmetic products in Pakistan. The results of mediation indicate that PJ is playing partial mediation in this relation.

This study is for the first time that is conducted in the context of India and Pakistan. Similarly, PJ is tested as a mediator for the first time in the relationship between CE and CA and BI and BL. This study would be beneficial for foreign brands generally and for Indian cosmetic brands specifically. In addition, it may provide help to business students and scholars to further understand and explore these variables in the context of developing countries.