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Article
Publication date: 2 January 2020

Aatef Hobiny and Ibrahim Abbas

The purpose of this paper is to provide a method for determining the numerical solutions of the thermal damage of cylindrical living tissues using hyperbolic bioheat model. Due to…

191

Abstract

Purpose

The purpose of this paper is to provide a method for determining the numerical solutions of the thermal damage of cylindrical living tissues using hyperbolic bioheat model. Due to the complex governing equation, the finite element approach has been adopted to solve these problems. To approve the accuracy of the numerical solution, the numerical outcomes obtained by the finite element approach are compared with the existing experimental study. In addition, the comparisons between the numerical outcomes and the existing experimental data displays that the present mathematical models are efficient tools to evaluate the bioheat transfer in the cylindrical living tissue. Numerical computations for temperatures and thermal damage are presented graphically.

Design/methodology/approach

In this section, the complex equation of bioheat transfer based upon one relaxation time in cylindrical living tissue is summarized by using the finite element method. This method has been used here to get the solution of equation (8) with initial conditions (9) and boundary conditions (10). The finite element technique is a strong method originally advanced for numerical solutions of complex problems in many fields, and it is the approach of choice for complex systems. Another advantage of this method is that it makes it possible to visualize and quantify the physical effects independently of the experimental limits. Abbas and his colleagues [26-34] have solved several problems under generalized thermoelastic theories.

Findings

In this study, the different values of blood perfusion and thermal relaxation time of the dermal part of cylindrical living tissue are used. To verify the accuracy of the numerical solutions, the numerical outcomes obtained by the finite element procedure and the existing experimental study have been compared. This comparison displays that the present mathematical model is an effective tool to evaluate the bioheat transfer in the living tissue.

Originality/value

The validation of the obtained results by using experimental data the numerical solution of hyperbolic bioheat equation is presented. Due to the nonlinearity of the basic equation, the finite element approach is adopted. The effects of thermal relaxation times on the thermal damage and temperature are studied.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 8
Type: Research Article
ISSN: 0961-5539

Keywords

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Article
Publication date: 21 February 2020

Aatef Hobiny and Ibrahim Abbas

The purpose of this study is to use the generalized model for thermoelastic wave under the dual phase lag (DPL) model to compute the increment of temperature, the components of…

196

Abstract

Purpose

The purpose of this study is to use the generalized model for thermoelastic wave under the dual phase lag (DPL) model to compute the increment of temperature, the components of displacement, the changes in volume fraction field and the stress components in a two-dimensional (2D) porous medium.

Design/methodology/approach

Using Fourier and Laplace transformations with the eigenvalue technique, the exact solutions of all physical quantities are obtained.

Findings

The derived method is evaluated with numerical results, which are applied to the porous medium in a simplified geometry.

Originality/value

Finally, the outcomes are graphically represented to show the difference among the models of classical dynamical coupled, the Lord and Shulman and DPL.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 11
Type: Research Article
ISSN: 0961-5539

Keywords

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Article
Publication date: 9 October 2020

Ibrahim Abbas and Aatef Hobiny

The purpose of this paper is to study the wave propagation in a porous medium through the porothermoelastic process using the finite element method (FEM).

96

Abstract

Purpose

The purpose of this paper is to study the wave propagation in a porous medium through the porothermoelastic process using the finite element method (FEM).

Design/methodology/approach

One-dimensional (1D) application for a poroelastic half-space is considered. Due to the complex governing equation, the finite element approach has been adopted to solve these problems.

Findings

The effect of porosity and thermal relaxation times in a porothermoelastic material was investigated.

Originality/value

The numerical results for stresses, displacements and temperatures for the solid and the fluid are represented graphically. This work will enable future investigators to have the insight of nonsimple porothermoelasticity with different phases in detail.

Details

Multidiscipline Modeling in Materials and Structures, vol. 17 no. 2
Type: Research Article
ISSN: 1573-6105

Keywords

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Article
Publication date: 23 April 2020

Aatef Hobiny, Faris S. Alzahrani and Ibrahim Abbas

The purposes of this study, a generalized model for thermoelastic wave under three-phase lag (TPL) model is used to compute the increment of temperature, the components of…

135

Abstract

Purpose

The purposes of this study, a generalized model for thermoelastic wave under three-phase lag (TPL) model is used to compute the increment of temperature, the components of displacement, the changes in volume fraction field and the stress components in a two-dimension porous medium.

Design/methodology/approach

By using Laplace-Fourier transformations with the eigen values methodologies, the analytical solutions of all physical variables are obtained.

Findings

The derived methods are estimated with numerical outcomes which are applied to the porous media in simplified geometry.

Originality/value

Finally, the outcomes are represented graphically to display the difference among the models of the TPL and the Green and Naghdi (GNIII) with and without energy dissipations.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 12
Type: Research Article
ISSN: 0961-5539

Keywords

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Article
Publication date: 8 January 2020

Tareq Saeed and Ibrahim Abbas

The purposes of this study, a mathematical model of generalized thermoelastic theory subjected to thermal loading is presented to study the wave propagation in a two-dimensional…

128

Abstract

Purpose

The purposes of this study, a mathematical model of generalized thermoelastic theory subjected to thermal loading is presented to study the wave propagation in a two-dimensional porous medium.

Design/methodology/approach

By using Fourier–Laplace transforms with the eigenvalue approach, the physical quantities are analytically obtained.

Findings

The derived method is evaluated with numerical results, which are applied to the porous medium in simplified geometry.

Originality/value

Numerical outcomes for all the physical quantities considered are implemented and represented graphically. The variations of temperature, the changes in volume fraction field, the displacement components and the stress components have been depicted graphically.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 8
Type: Research Article
ISSN: 0961-5539

Keywords

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Article
Publication date: 21 June 2018

Aatef Hobiny and Ibrahim Abbas

The purpose of this paper is to study the wave propagation in a non-homogenous semiconducting medium through the photothermal process using the fractional order…

76

Abstract

Purpose

The purpose of this paper is to study the wave propagation in a non-homogenous semiconducting medium through the photothermal process using the fractional order photo-thermoelastic without neglecting the coupling between the plasma and thermoelastic waves that photogenerated through traction free and loaded thermally by exponentially decaying pulse boundary heat flux.

Design/methodology/approach

The analytical solutions in the transformed domain by the eigenvalue approach were observed through the transform techniques of Laplace.

Findings

Silicon-like semiconductor was used to achieve the numerical computations.

Originality/value

Some comparisons are shown in the figures to estimate the effects of the fractional order and non-homogeneous parameters.

Details

Multidiscipline Modeling in Materials and Structures, vol. 14 no. 5
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 1 February 1995

Magda El‐Sherbini

Najib Mahfuz is the first Arab‐language author to win the Nobel Prize in literature. Born in 1911 the son of a middle‐class Jamaliyah merchant, he became the most popular novelist…

111

Abstract

Najib Mahfuz is the first Arab‐language author to win the Nobel Prize in literature. Born in 1911 the son of a middle‐class Jamaliyah merchant, he became the most popular novelist in Egypt and the Arab countries.

Details

Reference Services Review, vol. 23 no. 2
Type: Research Article
ISSN: 0090-7324

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Expert briefing
Publication date: 25 April 2023

The economic crisis and political vacuum have resulted in a rise in crimes-for-profit including kidnappings and burglaries, many by people posing as security personnel. Meanwhile…

Details

DOI: 10.1108/OXAN-DB278627

ISSN: 2633-304X

Keywords

Geographic
Topical
Available. Open Access. Open Access
Article
Publication date: 30 November 2022

Attia Aman-Ullah, Azelin Aziz, Hadziroh Ibrahim, Waqas Mehmood and Attiqa Aman-Ullah

This research aimed to study the impact of compensation on employee retention and turnover intentions among healthcare employees. The study also tested the mediation role of job…

9988

Abstract

Purpose

This research aimed to study the impact of compensation on employee retention and turnover intentions among healthcare employees. The study also tested the mediation role of job satisfaction in the relationship.

Design/methodology/approach

In the present study, self-administrated questionnaires were distributed among 600 doctors working in public hospitals of Pakistan, following stratified sampling. The data analysis was conducted through SPSS and smart-PLS.

Findings

Results of the present study supported all the hypotheses (H1–H7), such as the significant relationship of compensation with employee retention and turnover intentions. Results further confirmed the mediation effect of job satisfaction between compensation and employee retention as well as compensation and turnover intentions.

Practical implications

This study is useful for policymakers and organizational managers since the study provides guidelines on employee retention and high turnover intentions and how these factors are influenced by improved compensation.

Originality/value

This study sheds light on the relationship of compensation together with employee retention and turnover intentions through the mediating role of job satisfaction in healthcare context, which was overlooked in the existing literature.

Details

Revista de Gestão, vol. 30 no. 2
Type: Research Article
ISSN: 1809-2276

Keywords

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Article
Publication date: 9 April 2010

Ezimma Kate Nwadiogwa Nnabuife

The purpose of this paper is to examine the current gap existing between ethics theorization and enforcement in the Nigerian leadership system.

1954

Abstract

Purpose

The purpose of this paper is to examine the current gap existing between ethics theorization and enforcement in the Nigerian leadership system.

Design/methodology/approach

In an attempt to achieve the objective of the paper, some ethical issues in the Nigerian governance and the several regulatory and enforcement agencies set up to curb ethical menace were critically examined. The achievements of the bodies were also evaluated.

Findings

The paper concludes that the apparent gap which continues to exist is not a function of ethical definition but results from challenges in the enforcement which are thematically grouped under leadership, societal and individual variables.

Research limitations/implications

The analysis suggests that bridging the ethical gap in Nigeria depends largely on leadership which must be by example.

Originality/value

This paper presents an invaluable challenge to leadership in Nigeria who must reposition their responsibility.

Details

African Journal of Economic and Management Studies, vol. 1 no. 1
Type: Research Article
ISSN: 2040-0705

Keywords

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