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Article
Publication date: 7 December 2020

Fahimeh Esnaasharan, Mansour Alizadeh, Parvin Ayremlou and Rasoul Zarrin

The purpose of this study is to investigate the relationship between pH of water or other daily fluid intake and risk of kidney stones in adult men.

204

Abstract

Purpose

The purpose of this study is to investigate the relationship between pH of water or other daily fluid intake and risk of kidney stones in adult men.

Design/methodology/approach

This case–control study included 120 adult men with kidney stones and 240 healthy controls matched by age. Participants were selected from the Urmia Imam Khomeini Educational Hospital in the northwest of Iran by the available sampling method between 2017 and 2018. The mean total daily fluid intake of the subjects over the past one year period was collected using a validated 139-item Food Frequency Questionnaire, and the pH of drinking water samples consumed over the past six months was determined using an electrochemical pH meter. Information on physical activity level and socio-demographic characteristics of all participants was collected.

Findings

The mean pH of daily water consumption was 7.1 ± 250.3 and 7.4%± 250.3 in case and control groups, respectively. In multivariate logistic regression analysis after adjusting for the covariates 25 a significant relationship was detected between the pH of drinking water (not for other fluid intake26) and kidney stone disease (OR = 0.15, CI 0.06–0.4, P > 1. Moreover, no association was found between the volume of total fluid intake and risk of kidney stones.

Originality/value

These findings support potential protective effects of drinking water intake with higher pH level on preventing kidney stones.

Details

Nutrition & Food Science , vol. 51 no. 6
Type: Research Article
ISSN: 0034-6659

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Article
Publication date: 31 December 2010

Nisrine Mansour

With a history of social and political marginalisation, mobile populations are most deprived of access to adequate health service provision. While they have undergone…

625

Abstract

With a history of social and political marginalisation, mobile populations are most deprived of access to adequate health service provision. While they have undergone sociopolitical changes that bring them closer to mainstream health provision, their perception of the available health provision is still rarely sought by policy makers. This paper addresses these gaps by exploring the perceptions that Bedouin women have of reproductive health services in the Bekaa valley of Lebanon. Historically at the margins of health policy making, Bedouin populations in Lebanon have recently been facing significant sociopolitical changes to their ways of life that affect their perceptions of access and use of health services. In the past 40 years, the Bedouin have gradually settled in informal permanent or quasi‐permanent settlements and engaged with modernised sedentary modes of living overlapping with their own. Their entitlements to social provision and political participation were also renegotiated in the post‐conflict political era (post‐1990) through an inconsistent naturalisation process managed by dominant political players. These changes have been significant in reshaping the positioning of the Bedouin as a social group in the broader Lebanese society. Against this backdrop, the paper asks the following question: How do women negotiate their reproductive health issues in relation to the dominant Lebanese mixed‐provider health model? The paper argues that Bedouin women's perceptions of, and engagement with, the health system are hindered more by the inconsistencies and shortfalls of the health system than by any specific barriers stemming from their ways of life. Their access and use of health services are underpinned by institutional discrimination against their ethnic group at various levels of health provision.

Details

International Journal of Migration, Health and Social Care, vol. 6 no. 3
Type: Research Article
ISSN: 1747-9894

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Article
Publication date: 8 August 2022

Mohammad Shahid, Zubair Ashraf, Mohd Shamim and Mohd Shamim Ansari

Optimum utilization of investments has always been considered one of the most crucial aspects of capital markets. Investment into various securities is the subject of portfolio…

135

Abstract

Purpose

Optimum utilization of investments has always been considered one of the most crucial aspects of capital markets. Investment into various securities is the subject of portfolio optimization intent to maximize return at minimum risk. In this series, a population-based evolutionary approach, stochastic fractal search (SFS), is derived from the natural growth phenomenon. This study aims to develop portfolio selection model using SFS approach to construct an efficient portfolio by optimizing the Sharpe ratio with risk budgeting constraints.

Design/methodology/approach

This paper proposes a constrained portfolio optimization model using the SFS approach with risk-budgeting constraints. SFS is an evolutionary method inspired by the natural growth process which has been modeled using the fractal theory. Experimental analysis has been conducted to determine the effectiveness of the proposed model by making comparisons with state-of-the-art from domain such as genetic algorithm, particle swarm optimization, simulated annealing and differential evolution. The real datasets of the Indian stock exchanges and datasets of global stock exchanges such as Nikkei 225, DAX 100, FTSE 100, Hang Seng31 and S&P 100 have been taken in the study.

Findings

The study confirms the better performance of the SFS model among its peers. Also, statistical analysis has been done using SPSS 20 to confirm the hypothesis developed in the experimental analysis.

Originality/value

In the recent past, researchers have already proposed a significant number of models to solve portfolio selection problems using the meta-heuristic approach. However, this is the first attempt to apply the SFS optimization approach to the problem.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 16 no. 2
Type: Research Article
ISSN: 1756-378X

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Article
Publication date: 20 May 2022

Mansour Abedian, Atefeh Amindoust, Reza Maddahi and Javid Jouzdani

This paper aims to propose an integrated centralized data envelopment analysis (CDEA)-balanced scorecard (BSC) model to provide a selective approach to determine the most…

232

Abstract

Purpose

This paper aims to propose an integrated centralized data envelopment analysis (CDEA)-balanced scorecard (BSC) model to provide a selective approach to determine the most efficient indicators for evaluating the four perspectives of the BSC.

Design/methodology/approach

An integer linear programming model based on the efficiency concept of the CDEA method is presented to select the best indicators for evaluating four perspectives of the BSC. The basis for selecting indicators in this method is to maximize the overall performance of each BSC perspective. The modeling is performed on a real case. The considered model is solved using a general algebraic modeling system software for the data set of the real case.

Findings

A real-world case is solved using the proposed method. The integration of the CDEA and the BSC seems to be advantageous because it sheds more light on the complexity and tradeoffs inherent in actual performance measurement. It is important to note that there cannot be a unique and universal model of performance measurement applicable in every situation, in every organization and at any time.

Research limitations/implications

The data set of a single organization in the manufacturing industry is used to show the performance of the proposed mathematical model; therefore, generalization of the results should be done cautiously. This framework is based on the Iranian community and experts’ viewpoints; therefore, different results may be obtained if it is applied elsewhere, and the importance of perspectives and their indicators might show different results in other populations and other countries. In addition, because the data is collected in a specific period of time, the results cannot be extended to other periods of time.

Originality/value

The main contribution of this paper lies in the adaption of a new integrated CDEA-BSC model to performance measurement in the industrial sector that technology improves the ultimate results of performance measurement and provides wider opportunities for decision-makers. This paper aids managers and decision-makers to control the efficient indicators in perspectives.

Details

Journal of Modelling in Management, vol. 18 no. 2
Type: Research Article
ISSN: 1746-5664

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Article
Publication date: 19 September 2022

Feda Abdalla Zahor, Reema Jain, Ahmada Omar Ali and Verdiana Grace Masanja

The purpose of this paper is to review previous research studies on mathematical models for entropy generation in the magnetohydrodynamics (MHD) flow of nanofluids. In addition…

295

Abstract

Purpose

The purpose of this paper is to review previous research studies on mathematical models for entropy generation in the magnetohydrodynamics (MHD) flow of nanofluids. In addition, the influence of various parameters on the velocity profiles, temperature profiles and entropy generation was studied. Furthermore, the numerical methods used to solve the model equations were summarized. The underlying purpose was to understand the research gap and develop a research agenda.

Design/methodology/approach

This paper reviews 141 journal articles published between 2010 and 2022 on topics related to mathematical models used to assess the impacts of various parameters on the entropy generation, heat transfer and velocity of the MHD flow of nanofluids.

Findings

This review clarifies the application of entropy generation mathematical models, identifies areas for future research and provides necessary information for future research in the development of efficient thermodynamic systems. It is hoped that this review paper can provide a basis for further research on the irreversibility of nanofluids flowing through different channels in the development of efficient thermodynamic systems.

Originality/value

Entropy generation analysis and minimization constitute effective approaches for improving the performance of thermodynamic systems. A comprehensive review of the effects of various parameters on entropy generation was performed in this study.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 33 no. 2
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 30 April 2020

Zehba Raizah, Mitsuteru Asai and Abdelraheem M. Aly

The purpose of this study is to apply the incompressible smoothed particle hydrodynamics (ISPH) method to simulate the natural convection flow from an inner heated Y-fin inside…

111

Abstract

Purpose

The purpose of this study is to apply the incompressible smoothed particle hydrodynamics (ISPH) method to simulate the natural convection flow from an inner heated Y-fin inside Y-shaped enclosure filled with nanofluid.

Design/methodology/approach

The dimensionless governing partial differential equations are described in the Lagrangian form and solved by an implicit scheme of the ISPH method. The embedded Y-fin is kept at a high temperature Th with variable heights during the simulations. The lower area of Y-shaped enclosure is squared with width L = 1 m and its side-walls are kept at a low temperature Tc. The upper area of the Y-shaped enclosure is V-shaped with width 0.5 L for each side and its walls are adiabatic.

Findings

The performed simulations revealed that the height of the inner heated Y-fin plays an important role in the heat transfer and fluid flow inside the Y-shaped enclosure, where it enhances the heat transfer. Rayleigh number augments the buoyancy force inside the Y-shaped enclosure and, consequently, it has a strong impact on temperature distributions and strength of the fluid flow inside Y-shaped enclosure. Adding more concentration of the nanofluid until 10% has a slight effect on the temperature distributions and it reduces the strength of the fluid flow inside Y-shaped enclosure. In addition, the average Nusselt number is measured along the inner heated Y-fin and it grows as the Rayleigh number increases. The average Nusselt number is decreasing by adding more concentrations of the nanofluid.

Originality/value

An improved ISPH method is used to simulate the natural convection flow of Y-fin embedded in the Y-shaped enclosure filled with a nanofluid.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 31 no. 1
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 17 December 2019

B.J. Gireesha and S. Sindhu

Fully developed Casson fluid flow through vertical microchannel is deliberated in the presence of thermal radiation. The two predominant features of micro scale phenomenon such as…

87

Abstract

Purpose

Fully developed Casson fluid flow through vertical microchannel is deliberated in the presence of thermal radiation. The two predominant features of micro scale phenomenon such as velocity slip and temperature jump are considered. The paper aims to discuss this issue.

Design/methodology/approach

The governing equations of the physical phenomenon are solved using Runge–Kutta–Fehlberg fourth fifth order method.

Findings

The outcome of the present work is discussed through graphs. This computation shows that entropy generation rate decreases with enhancing wall ambient temperature difference ratio and fluid wall interaction parameter. Also, it is found that Bejan number is fully retarded with rise in fluid wall interaction parameter. Enhancement in heat transfer or Nusselt number is achieved by increasing the wall ambient temperature ratio and fluid wall interaction parameter.

Originality/value

Casson liquid flow through microchannel is analyzed by considering temperature jump and velocity slip. This computation shows that entropy generation rate decreases with enhancing wall ambient temperature difference ratio.

Details

Multidiscipline Modeling in Materials and Structures, vol. 16 no. 4
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 1 June 1997

Jaroslav Mackerle

Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the…

6101

Abstract

Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view. The range of applications of FEMs in this area is wide and cannot be presented in a single paper; therefore aims to give the reader an encyclopaedic view on the subject. The bibliography at the end of the paper contains 2,025 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1992‐1995.

Details

Engineering Computations, vol. 14 no. 4
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 12 September 2023

Kemal Subulan and Adil Baykasoğlu

The purpose of this study is to develop a holistic optimization model for an integrated sustainable fleet planning and closed-loop supply chain (CLSC) network design problem under…

392

Abstract

Purpose

The purpose of this study is to develop a holistic optimization model for an integrated sustainable fleet planning and closed-loop supply chain (CLSC) network design problem under uncertainty.

Design/methodology/approach

A novel mixed-integer programming model that is able to consider interactions between vehicle fleet planning and CLSC network design problems is first developed. Uncertainties of the product demand and return fractions of the end-of-life products are handled by a chance-constrained stochastic program. Several Pareto optimal solutions are generated for the conflicting sustainability objectives via compromise and fuzzy goal programming (FGP) approaches.

Findings

The proposed model is tested on a real-life lead/acid battery recovery system. By using the proposed model, sustainable fleet plans that provide a smaller fleet size, fewer empty vehicle repositions, minimal CO2 emissions, maximal vehicle safety ratings and minimal injury/illness incidence rate of transport accidents are generated. Furthermore, an environmentally and socially conscious CLSC network with maximal job creation in the less developed regions, minimal lost days resulting from the work's damages during manufacturing/recycling operations and maximal collection/recovery of end-of-life products is also designed.

Originality/value

Unlike the classical network design models, vehicle fleet planning decisions such as fleet sizing/composition, fleet assignment, vehicle inventory control, empty repositioning, etc. are also considered while designing a sustainable CLSC network. In addition to sustainability indicators in the network design, sustainability factors in fleet management are also handled. To the best of the authors' knowledge, there is no similar paper in the literature that proposes such a holistic optimization model for integrated sustainable fleet planning and CLSC network design.

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Article
Publication date: 5 February 2024

Prabir Barman, Srinivasa Rao Pentyala and B.V. Rathish Kumar

A porous cavity flow field generates entropy owing to energy and momentum exchange within the fluid and at solid barriers. The heat transport and viscosity effects on fluid and…

123

Abstract

Purpose

A porous cavity flow field generates entropy owing to energy and momentum exchange within the fluid and at solid barriers. The heat transport and viscosity effects on fluid and solid walls irreversibly generate entropy. This numerical study aims to investigate convective heat transfer together with entropy generation in a partially heated wavy porous cavity filled with a hybrid nanofluid.

Design/methodology/approach

The governing equations are nondimensionalized and the domain is transformed into a unit square. A second-order finite difference method is used to have numerical solutions to nondimensional unknowns such as stream function and temperature. This numerical computation is conducted to explore a wide range of regulating parameters, e.g. hybrid nano-particle volume fraction (σ = 0.1%, 0.33%, 0.75%, 1%, 2%), Rayleigh–Darcy number (Ra = 10, 102, 103), dimensionless length of the heat source (ϵ = 0.25, 0.50,1.0) and amplitude of the wave (a = 0.05, 0.10, 0.15) for a number of undulations (N = 1, 3) per unit length.

Findings

A thorough analysis is conducted to analyze the effect of multiple factors such as thermal convective forces, heat source, surface corrugation factors, nanofluid volume fraction and other parameters on entropy generation. The flow and temperature fields are studied through streamlines and isotherms. The average Bejan number suggested that entropy generation is entirely dominated by irreversibility due to heat transport at Ra = 10, and the irreversibility due to the viscosity effect is severe at Ra = 103, but the increment in s augments irreversibility due to the viscosity effect over the heat transport at Ra = 102.

Originality/value

To the best of the authors’ knowledge, this numerical study, for the first time, analyzes the influence of surface corrugation on the entropy generation related to the cooling of a partial heat source by the convection of a hybrid nanofluid.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 2
Type: Research Article
ISSN: 0961-5539

Keywords

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