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Book part
Publication date: 13 November 2023

Jelena Balabanić Mavrović

Abstract

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Eating Disorders in a Capitalist World
Type: Book
ISBN: 978-1-80455-787-7

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Article
Publication date: 12 January 2010

J.W. Peterson, B.T. Murray and G.F. Carey

The purpose of this paper is to consider double‐diffusive convection in a heated porous medium saturated with a fluid. Of particular interest is the case where the fluid has a…

507

Abstract

Purpose

The purpose of this paper is to consider double‐diffusive convection in a heated porous medium saturated with a fluid. Of particular interest is the case where the fluid has a stabilizing concentration gradient and small diffusivity.

Design/methodology/approach

A fully‐coupled stabilized finite element scheme and adaptive mesh refinement (AMR) methodology are introduced to solve the resulting coupled multiphysics application and resolve fine scale solution features. The code is written on top of the open source finite element library LibMesh, and is suitable for parallel, high‐performance simulations of large‐scale problems.

Findings

The stabilized adaptive finite element scheme is used to compute steady and unsteady onset of convection in a generalized Horton‐Rogers‐Lapwood problem in both two and three‐dimensional domains. A detailed study confirming the applicability of AMR in obtaining the predicted dependence of solutal Nusselt number on Lewis number is given. A semi‐permeable barrier version of the generalized HRL problem is also studied and is believed to present an interesting benchmark for AMR codes owing to the different boundary and internal layers present in the problem. Finally, some representative adaptive results in a complex 3D heated‐pipe geometry are presented.

Originality/value

This work demonstrates the feasibility of stabilized, adaptive finite element schemes for computing simple double‐diffusive flow models, and it represents an easily‐generalizable starting point for more complex calculations since it is based on a highly‐general finite element library. The complementary nature of h‐adaptivity and stabilized finite element techniques for this class of problem is demonstrated using particularly simple error indicators and stabilization parameters. Finally, an interesting double‐diffusive convection benchmark problem having a semi‐permeable barrier is suggested.

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International Journal of Numerical Methods for Heat & Fluid Flow, vol. 20 no. 1
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 12 February 2018

Mahantesh S. Swamy

This paper aims to investigate the onset of convection, heat and mass transports in a sparse porous layer saturated with chemically reactive binary fluid mixture heated and salted…

48

Abstract

Purpose

This paper aims to investigate the onset of convection, heat and mass transports in a sparse porous layer saturated with chemically reactive binary fluid mixture heated and salted from below under the influence of Soret and Dufour effects.

Design/methodology/approach

The Brinkman model is used for momentum equation. Linear stability analysis based on normal mode technique is used to evaluate the onset threshold for stationary and oscillatory convection. In weak-nonlinear theory, the truncated Fourier series method is used. The resulting system of differential equations is solved numerically by using the Runge–Kutta fourth-order method.

Findings

Because of the competition between the processes of thermal, solute diffusions, chemical reaction and cross-diffusions, the onset of instability is via oscillatory mode instead of stationary. The effect of dissolution/precipitation of reactive component and the cross-diffusions on the stability, heat and mass transports is investigated.

Originality/value

By the proper adjustment of underlying parameters, the onset of convection can either be advanced or delayed as per the requirement. Therefore, the present investigation forms a useful tool for regulating the onset of convection.

Details

World Journal of Engineering, vol. 15 no. 1
Type: Research Article
ISSN: 1708-5284

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Book part
Publication date: 12 September 2018

Rachel Dodds, Brittany Jenkins, Wayne Smith and Robert E. Pitts

Sales and purchases of socially and environmentally responsible festival clothing are a way for festival attendees to engage in ethical consumption and for event organizers to…

Abstract

Sales and purchases of socially and environmentally responsible festival clothing are a way for festival attendees to engage in ethical consumption and for event organizers to undertake sustainable procurement. Although there have been a number of studies examining willingness-to-pay (WTP), few of them examine this in a festival setting, and there is a gap in existing research regarding the determination of actual behavior. The goal of this study is therefore to explore participants’ willingness-to-pay for apparel based on more external motivations (visible environmental messages) and then ascertain whether this behavior was actually replicated in a natural field setting. This study first collected surveys from 427 festival-goers in 2015, then used a natural field experiment in 2016 to investigate whether attendees at the Mariposa Folk Festival in Ontario, Canada, would actually be prepared to pay a premium for ethical festival T-shirts over a conventional alternative. The findings reveal that attendees not only showed a willingness-to-pay but they also did actually pay a premium for such T-shirts.

Details

Contemporary Challenges of Climate Change, Sustainable Tourism Consumption, and Destination Competitiveness
Type: Book
ISBN: 978-1-78756-343-8

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Article
Publication date: 28 October 2014

Rtibi Ahmed, Hasnaoui Mohammed and Amahmid Abdelkhalk

The purpose of this paper is to study analytically and numerically the effect of a transverse magnetic field on the separation of species induced in an inclined rectangular porous…

120

Abstract

Purpose

The purpose of this paper is to study analytically and numerically the effect of a transverse magnetic field on the separation of species induced in an inclined rectangular porous cavity saturated with an electrically conducting mixture.

Design/methodology/approach

The porous layer is assumed homogeneous and submitted from its long sides to uniform heat fluxes and to a magnetic field of strength B. The Darcy model combined with the Boussinesq approximation are used to study the heat and solute transfer in the medium. An analytical solution is developed on the basis of the parallel flow approximation. Numerical simulations are also performed in order to validate the analytical solution. The controlling parameters of this problem are the thermal Rayleigh number, the inclination of the enclosure, the separation parameter, the Hartmann number and the Lewis number.

Findings

For given values of the thermal Rayleigh number, the inclination of the enclosure, the separation parameter and the Lewis number, there is an optimal magnetic field which leads to a maximum of separation. At relatively high Rayleigh numbers, where convection destroys the separation process, it is possible, with an optimal choice of the Hartman number, to recover a good level of separation.

Research limitations/implications

Since the problem is governed by several parameters (five parameters), only the Darcy model was used in this study instead of the Darcy-Brinkman extended model even if the latter model allows to cover the pure fluid and Darcy porous media as limiting cases.

Practical implications

In separation experiments, it is very difficult technically to work with small Rayleigh numbers due to technical difficulties. However, the process of separations is canceled at high Rayleigh number by the strength of convection which causes a mixing in the binary mixture. This study shows that, by using adequate combinations of the controlling parameters, it becomes possible to reach a good level of separation even at relatively high Rayleigh numbers.

Originality/value

Optimum choice of the magnetic field and the inclination of the cavity may lead to a good level of the separation process. For large Lewis numbers, the separation vanishes far above and far below the optimal Ha. However, for small Lewis numbers, an important level of separation is maintained for any Ha located below the optimal value of the latter parameter.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 24 no. 8
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 1 May 1993

BALASUBRAMANIAM RAMASWAMY

Sinusoidal gravity modulation fields imposed on two‐dimensional Rayleigh‐Benard convection flow are studied to understand the effects of periodic source (g‐jitter) on fluids…

89

Abstract

Sinusoidal gravity modulation fields imposed on two‐dimensional Rayleigh‐Benard convection flow are studied to understand the effects of periodic source (g‐jitter) on fluids system and heat transfer mechanism. The transient Navier‐Stokes and energy equations are solved by semi‐implicit operator splitting finite element method. Results include two sets. One is considered at normal terrestrial condition and the other one is related to low‐gravity condition. Under low‐gravity condition the research focuses on the effects of modulation frequency and direction in order to find out the critical frequency for heat transfer mechanism transferring from conduction to convection.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 3 no. 5
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 1 May 2023

Hajar Regragui, Naoufal Sefiani, Hamid Azzouzi and Naoufel Cheikhrouhou

Hospital structures serve to protect and improve public health; however, they are recognized as a major source of environmental degradation. Thus, an effective performance…

385

Abstract

Purpose

Hospital structures serve to protect and improve public health; however, they are recognized as a major source of environmental degradation. Thus, an effective performance evaluation framework is required to improve hospital sustainability. In this context, this study presents a holistic methodology that integrates the sustainability balanced scorecard (SBSC) with fuzzy Delphi method and fuzzy multi-criteria decision-making approaches for evaluating the sustainability performance of hospitals.

Design/methodology/approach

Initially, a comprehensive list of relevant sustainability evaluation criteria was considered based on six SBSC-based dimensions, in line with triple-bottom-line sustainability dimensions, and derived from the literature review and experts’ opinions. Then, the weights of perspectives and their respective criteria are computed and ranked utilizing the fuzzy analytic hierarchy process. Subsequently, the hospitals’ sustainable performance values are ranked based on these criteria using the Fuzzy Technique for Order of Preference by Similarity to Ideal Solution.

Findings

A numerical application was conducted in six public hospitals to exhibit the proposed model’s applicability. The results of this study revealed that “Patient satisfaction,” “Efficiency,” “Effectiveness,” “Access to care” and “Waste production,” respectively, are the five most important criteria of sustainable performance.

Practical implications

The new model will provide decision-makers with management tools that may help them identify the relevant factors for upgrading the level of sustainability in their hospitals and thus improve public health and community well-being.

Originality/value

This is the first study that proposes a new hybrid decision-making methodology for evaluating and comparing hospitals’ sustainability performance under a fuzzy environment.

Details

International Journal of Productivity and Performance Management, vol. 73 no. 3
Type: Research Article
ISSN: 1741-0401

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Article
Publication date: 21 January 2025

Boadi Agyekum, Inusah Salifu, Samuel Nuamah Eshun and Moses Kumi Asamoah

The purpose of this article is to increase understanding of the relationship between parent-teacher associations (PTAs) activities and school-community development, with a…

14

Abstract

Purpose

The purpose of this article is to increase understanding of the relationship between parent-teacher associations (PTAs) activities and school-community development, with a particular emphasis on the ways in which PTAs are utilized as supplemental or alternative sources of funding or support for school self-development initiatives.

Design/methodology/approach

The article is based on a case study conducted in two Ghanaian elementary schools. Field notes, in-depth interviews and observations of PTA members (n = 21) and activities make up the data. The article theoretically adopts a community development practice that is predicated on promoting solidarity and agency by upholding the ideas of felt needs, self-help and participation.

Findings

The study revealed that PTA initiatives can improve the diversity of activities available within a school while also building the skills and capacity of local communities and enabling individuals to make social connections. The study mainly recommended that in making educational systems resilient, such school-community-based resources of resilience should be preserved, fostered and valued.

Practical implications

The findings are practically relevant to local school managers and other stakeholders involved in school leadership, promoting the relationships between PTAs, school management, children’s well-being and community development, particularly in sub-Saharan African schools like those in Ghana.

Originality/value

This article explores PTA’s involvement in school-community development in Ghana, a relatively under-researched area in this approach, using a community development practice approach, highlighting PTA’s impacts, implementation and challenges at elementary schools in the post-COVID era.

Details

Journal of Professional Capital and Community, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2056-9548

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Article
Publication date: 20 December 2023

Norazha Paiman, Muhammad Ashraf Fauzi, Natrika Norizan, Aida Abdul Rashid, Christine Nya-Ling Tan, Walton Wider, Kamalesh Ravesangar and Gowri Selvam

The research aims to provide a nuanced understanding of the complex social, psychological and organizational factors that serve as the foundation driving academics'…

241

Abstract

Purpose

The research aims to provide a nuanced understanding of the complex social, psychological and organizational factors that serve as the foundation driving academics' knowledge-sharing behavior (KSB) within an academic enclave.

Design/methodology/approach

A cross-sectional research design using the partial least squares structural equation modeling (PLS-SEM) approach was employed to examine the determinants of personality traits among tertiary academics in Malaysia in relation to their KSB. To this end, a self-administered survey was distributed to a sample group of 526 respondents.

Findings

It is evident that conscientiousness and agreeableness are the personality traits that play a significant role in promoting KSB among academics in higher learning institutions (HLIs). These personality traits are positively linked with academics' willingness to transfer and receive knowledge. In contrast, the personality trait of openness to experience does not significantly influence KSB.

Research limitations/implications

This study has employed a four-item measurement for evaluating the three distinct personality traits. Despite employing a brief measurement tool, the study has demonstrated significant reliability and validity, particularly in terms of convergent and discriminant validity.

Practical implications

The present study has revealed that conscientiousness in academics is intimately linked with their KSB, which is of paramount importance in the output-based education system. Notably, agreeableness among academics also conveys a positive effect on knowledge sharing (KS) in HLIs, as it cultivates trust and helpfulness among individuals and facilitates the exchange of valuable tacit knowledge.

Originality/value

This research explores the relationship between personality traits and KSB among Malaysian academics in HLIs. The study adopts the theories of planned behavior (TPB) and social capital theory (SCT) as theoretical ground, providing a nuanced understanding of the underlying motivations and mechanisms driving academics' knowledge-sharing behavior within the unique socio-cultural context of Southeast Asia.

Details

Journal of Applied Research in Higher Education, vol. 16 no. 5
Type: Research Article
ISSN: 2050-7003

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Article
Publication date: 14 June 2021

Jeffrey B. Allen

In this work, with a goal to ultimately forward the advancement of additive manufacturing research, the author applies the Wheeler-Boettinger-McFadden model through a progressive…

202

Abstract

Purpose

In this work, with a goal to ultimately forward the advancement of additive manufacturing research, the author applies the Wheeler-Boettinger-McFadden model through a progressive series of increasingly complex solidification problems illustrating the evolution of both dendritic as well as columnar growth morphologies. For purposes of convenience, the author assumes idyllic solutions (i.e. the excess energies associated with mixing solid and liquid phases can be neglected).

Design/methodology/approach

In this work, the author applied the phase-field model through a progressive series of increasingly complex solidification problems, illustrating the evolution of both dendritic as well as columnar growth morphologies. Beginning with a non-isothermal treatment of pure Ni, the author further examined the isothermal and directional solidification of Cu–Ni binary alloys.

Findings

(1) Consistent with previous simulation results, solidification simulations from each of the three cases revealed the presence of parabolic, dendrite tips evolving along directions of maximum interface energy. (2) For pure Ni simulations, changes in the anisotropy and noise magnitudes resulted in an increase of secondary dendritic branches and changes in the direction of propagation. The overall shape of the primary structure tended also to elongate with increased anisotropy. (3) For simulations of isothermal solidification of Ni–Cu binary alloys, the development of primary and secondary dendrite arm formation followed similar patterns associated with a pure substance. Calculations of dendrite tip velocity tended to increase monotonically with increasing anisotropy in accordance with previous research. (4) Simulations of directional solidification of Ni–Cu binary alloys with a linear temperature profile demonstrated the presence of cellular dendrites with relatively weak side-branching. The occurrence of solute trapping was also apparent between the primary dendrite columns. Dendrite tip velocities increased with increasing cooling rate.

Originality/value

This research, particularly the section devoted to directional solidification of binary alloys, describes a novel numerical framework and platform for the parametric analysis of various microstructural related quantities, including the effects due to changes in temperature gradient and cooling rate. Both the evolution of the phase and concentration are resolved.

Details

Multidiscipline Modeling in Materials and Structures, vol. 17 no. 5
Type: Research Article
ISSN: 1573-6105

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