Mohamed A. Mansour, Mohamed M. Abd‐Elaziz, Ramadan Abdalla and Sameh Elsayed
The purpose of this paper is to deal with unsteady double diffusive natural convection in a square enclosure filled with a porous medium with various boundary condition effects in…
Abstract
Purpose
The purpose of this paper is to deal with unsteady double diffusive natural convection in a square enclosure filled with a porous medium with various boundary condition effects in the presence of heat source or sink.
Design/methodology/approach
Finite difference method was employed to solve the dimensionless governing equations of the problem. The effects of governing parameters, namely, amplitude wave length ratio, dimensionless time parameter, Darcy number, buoyancy parameter and heat generation/absorption parameter on the streamlines, temperature and concentration contours, as well as Nusselt number and Sherwood number, were considered.
Findings
The sinusoidal variations of the temperature and concentration remove the singularities which appear in the case of fixed temperature and concentration.
Originality/value
The paper's results are validated by favorable comparisons with previously published results. The results of the problem are presented in graphical and tabular forms and discussed.
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The purpose of this paper is to argue that it is possible to identify a number of physical design properties of plots that are associated with coastal alteration and to develop a…
Abstract
Purpose
The purpose of this paper is to argue that it is possible to identify a number of physical design properties of plots that are associated with coastal alteration and to develop a predictive model or metric to evaluate the potential alteration caused by that resort. Investors may have economic plot size concerns not considered by planners, tourists may prefer close proximity to deep waters, and urban planners may have failed to realize the importance of certain plot ratios or minimum dimensions etc.
Design/methodology/approach
A combination of geographical information system and statistical tools is used to identify and model these properties. The research uses data from three different resorts in two countries along the Red Sea coast (Hurghada and Safaga in Egypt and Jeddah in Saudi Arabia). Landsat TM7 images are obtained for each location and analysed to detect regions with the largest alteration along the coast using the post‐classification change technique. Physical properties of each village are generated using ArcGIS 9.2 both before and after alteration. Finally, a predictive decision‐support tool for urban planners and environmental auditors is formulated using stepwise discriminant analysis.
Findings
Two‐step cluster analysis and discriminate analysis show that alteration takes place based on factors that include original width and original distance to deep water in three distinct groups. The predictive model that is developed classifies any given resort into one of three clusters, by virtue of their physical design characteristics. This gives a rough prediction of the likely alteration that might take place under a given condition. Subdivision plans that ignore the power of these two factors literally “invite” owners to violate shorelines and encroach on the sea. Planners are urged to join hands with policy makers and developers to formulate guidelines to plot subdivision and environmentally acceptable design solutions to facilitate access to deep water.
Originality/value
Till now, there has been no metric to relate a plot's geometric properties with the encroachment it makes. If such an association could be made, a developer's resort plans may be evaluated to predict the degree by which an encroachment is likely. The model can be used to identify resorts whose properties present a risk to shorelines, dredge or fill to maximize usable land. Two benefits may be thought of for this approach. First, the model helps urban planners develop a sustainable coastal area by bearing in mind the needs of tourist‐developers as well as the properties of their adjacent coast. Second, the factors can be used to rationalize building guidelines and land use regulations to minimize such risk.
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T. Javed, Z. Mehmood, M.A. Siddiqui and Ioan Pop
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Research limitations/implications
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.
Originality/value
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.
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Maisa Mohamed Ali Mansour, Rushdya Rabee Ali Hassan, Salwa Moustafa Amer Mahmoud and Youssif Mohamed Akl
This paper aims to identify the most common fungal species that grow on paper manuscripts and cause bio-deterioration. It also detects the impact of additive materials on fungal…
Abstract
Purpose
This paper aims to identify the most common fungal species that grow on paper manuscripts and cause bio-deterioration. It also detects the impact of additive materials on fungal degrading and builds a wide database. Thus, it helps conservators understand this phenomenon.
Design/methodology/approach
In total, 15 samples were collected from different paper manuscripts suffering from fungi. The achievement of the study objectives depends on using a variety of analyzes, such as a microbiological study, which indicated that three main fungi grew on the paper samples. Then, a digital microscope and an environmental scanning electron microscope were used to detect the effect of fungi on paper fibers. Fourier transform infrared microscopy was used to identify the binding medium and the X-ray diffraction method was used to measure the crystallinity index of cellulose of the paper samples.
Findings
Arabic gum was used as a binder medium with the samples. Aspergillus Niger, Aspergillus Fumigatus and Aspergillus Clavatus were the most common fungal species that grew on the Qur’an papers under investigation. They also caused much common damage to the paper samples. The results of the analyzes also showed that the highest crystallinity index of cellulose was in the samples that contained the lowest rate of fungal growth.
Originality/value
This paper highlights the relationship between fungal degradation and the multi-component nature of paper manuscripts. It builds a wide database that correlates the composition and the degradation of the Qur’an papers.
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Mohamed A. Saad, Fatma Metwaly, Sarah Yahia Gad, Khaled Mansour Mansour and Marwa A. Ali
The paper aims to use the Trilobal® polyester (Y cross-section) for producing fabrics suitable for fencing suits and evaluating their various properties.
Abstract
Purpose
The paper aims to use the Trilobal® polyester (Y cross-section) for producing fabrics suitable for fencing suits and evaluating their various properties.
Design/methodology/approach
Double weave structure was chosen to produce the samples by using six different face structures and two back structures divided into two groups according to the back structures. They were evaluated by their physical and mechanical properties such as tensile strength, puncture resistance, air permeability and humidity properties in horizontal and vertical wicking, drying rate and water vapor transmission.
Findings
Fencing sport recently is one of the most growing sports in the world, which necessitates special requirements and properties of fencing suit, either mechanical properties, which allow the easily and freely movement for the athlete, or the comfort properties that save the player’s effort and energy for a long time to improve his performance.
Originality/value
ANOVA test analysis showed highly significant results in some properties comparing back and face structures of the double weave fabric high correlation coefficient were found between packing density factor of produced fabric and the weft material types. The final results showed the produced sample that weaved with plain 1/1 for back structure and warp rib 2/2 for face structure achieved the best results, followed by the produced sample weaved with plain 1/1 for back structure and weft rib 2/2 for face structure compared with the other produced samples.
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Karam Mansour Ghazi, Islam Elbayoumi Salem, Hesham Dar and Ahmed Mohamed Elbaz
The purpose of this study was to examine the impact of strategic leadership (SL) on business operational resilience (OR) in the hotel industry in Egypt, namely, during and after…
Abstract
Purpose
The purpose of this study was to examine the impact of strategic leadership (SL) on business operational resilience (OR) in the hotel industry in Egypt, namely, during and after the pandemic. This investigation also aimed to explore the mediating function of crisis response strategies (CRSs) and organisational e-readiness (Oe-R) in this relationship.
Design/methodology/approach
The researchers conducted a cross-sectional study using a questionnaire as the primary data collection method. Using partial least squares structural equation simulation (PLS-SEM), the study used a comprehensive sample that targets the general managers of all five-star hotels in Egypt.
Findings
Results indicated that SL has a positive impact on CRSs and Oe-R. Furthermore, the results reveal a positive influence of Oe-R on both CRSs and hotel OR. On the other hand, CRSs do not influence hotel OR. The findings showed that CRSs fully mediate the link between SL and OR. However, CRSs do not serve as a mediator between Oe-R and OR. Furthermore, the findings showed that Oe-R partially mediates the link between SL and both OR and CRSs.
Practical implications
The study yields unique and valuable theoretical and practical insights to guide hotel leaders and managers towards adaptive recovery and resilience in turbulent and crisis-ridden environments by demonstrating that the combined mediating function of CRS and Oe-R is more effective in strengthening the relationship between SL and OR.
Originality/value
This study represents a pioneering investigation that establishes a correlation between SL and OR, either through direct or indirect means. The research examines the involvement of CRSs and Oe-R as collaborative mediators in this relationship. Previous studies undertaken in the hotel industry and service sector have not investigated this specific element.
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Walid Chaouali, Mohamed Yacine Haddoud, Mohamed Mousa, Ahmed Mohamed Elbaz, Narjess Aloui and Fawzi Dekhil
This study aims to investigate the impact of perceived subtle and overt discrimination on employees’ emotional exhaustion, along with potential mitigating factors such as social…
Abstract
Purpose
This study aims to investigate the impact of perceived subtle and overt discrimination on employees’ emotional exhaustion, along with potential mitigating factors such as social support, organizational inclusion and religiosity.
Design/methodology/approach
The research is based on a sample of 359 Muslim employees working in US restaurants. The data are analyzed using fuzzy-set Qualitative Comparative Techniques.
Findings
The results reveal that high/low emotional exhaustion in tourism and hospitality sector is triggered by multiple combinations of high/low levels of subtle and overt discrimination, family and friends support and religiosity. Such findings hold important implications to both theory and practice.
Research limitations/implications
By using fuzzy-set Qualitative Comparative Analysis, this research stands out from studies on discrimination that use conventional statistical methods. It proposes several solutions leading to a single outcome (high/low emotional exhaustion). This new approach contributes to the advancement of theory in this context.
Practical implications
This study shows that there is no single best solution for high/low emotional exhaustion. Stated differently, multiple solutions provide several ways for firms to mitigate employees’ emotional exhaustion.
Originality/value
Religious discrimination in workplaces is increasing at an alarming rate, particularly in customer facing roles, such as the tourism and hospitality industry. This is having detrimental effects on employees from minority groups, often leading to excessive levels of emotional exhaustion. Nonetheless, the extant literature has somewhat understated the consequences of this issue, creating a void that needs to be fulfilled. This study addresses this gap.
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Mohamed Hessian, Alaa Mansour Zalata and Khaled Hussainey
This study examines the effect of non-audit fees (NAF) provisions on interest payments classification shifting. In addition, we investigate to what extent the NAF economic bonding…
Abstract
Purpose
This study examines the effect of non-audit fees (NAF) provisions on interest payments classification shifting. In addition, we investigate to what extent the NAF economic bonding and interest payments classification shifting is contingent on internal governance and firm financial well-being.
Design/methodology/approach
This study employed probit regression using a sample of UK non-financial firms indexed in FT UK (500) over the period from 2009 to 2017.
Findings
We find evidence that the economic bonding of NAF between external auditors and their clients is more likely to encourage managers in UK firms to manipulate operating cash flows through interest payment classification shifting. In addition, and interestingly, our results evince that classification-shifting may be the less costly and soft choice of managers in firms with strong governance and charging higher NAF. Furthermore, we show that financially distressed firms associated with their auditors in purchasing non-audit services are more prone to attempting to manipulate and engage in interest payments classification-shifting. Our result did not provide a significant effect of external auditor tenure on the interest payments classification shifting.
Research limitations/implications
Our findings are subject to the following limitations: First, this study uses a composite index to measure the quality of internal corporate governance. It focuses only on the board of directors, but this index does not reflect other internal governance mechanisms. Second, this study is subject to limited study time due to the implementation of key IFRS standards (IFRS 9 Financial Instruments and IFRS 15 Revenue from Contract with Customers) from 2018–2019.
Practical implications
This study was motivated by the UK’s Financial Reporting Council regulators' pressure on the Big 4 audit firms to move more audit time into main auditing activities, reduce cross-selling to audit clients and separate their audit practices by 2024. Overall, we provide new evidence that directs a close spotlight on the threats of NAF that are potentially useful to regulators, shareholders and investors.
Originality/value
It is motivated by the UK’s Financial Reporting Council regulators' pressure on the Big 4 to move more audit firm time into main auditing activities, reduce cross-selling to audit clients and separate their audit practices by 2024. Overall, we provide new evidence that directs a close spotlight on the threats of NAS that are potentially useful to regulators, shareholders and investors.
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Mahmoud Abdelrahman Kamel, Mohamed El-Sayed Mousa and Randa Mohamed Hamdy
This study used data envelopment analysis (DEA) models to measure financial efficiency of twelve commercial banks listed in the Egyptian stock exchange (CBLSE), along with…
Abstract
Purpose
This study used data envelopment analysis (DEA) models to measure financial efficiency of twelve commercial banks listed in the Egyptian stock exchange (CBLSE), along with evaluating changes to the financial efficiency during the period 2017–2019.
Design/methodology/approach
The study used BCC-I, cross-efficiency, super-efficiency models, and Malmquist productivity index (MPI) to assess financial efficiency of the examined banks. The available data from both inputs and outputs were analyzed using R. studio V.I.3. 1056 software.
Findings
Out of twelve banks examined, only four banks were efficient under BCC-I model over different years of the study period; however, only one bank (CIB) appeared to be the most efficient compared to other peers in the study sample. Moreover, MPI results revealed decreased financial efficiency during the study period, due to the decreased technological innovation, except for HDB. Tobit regression results confirmed that total assets and total equity are significant factors impacted financial efficiency of CBLSE.
Practical implications
This study sheds light on the importance of evaluating financial efficiency of CBLSE to all stakeholders, to pinpoint weaknesses in banks' performance, and for evaluating financial policies and investment decisions.
Originality/value
Several studies sought to implement different models of DEA to assess banking performance in different regions of the world, but very few studies examined financial efficiency of banks. To the best of authors’ knowledge, this study is one of those few that addressed financial efficiency of banks in Egypt.
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Ahmed Hussein Aly and Mohamed Elsayed Mansour
The purpose of this paper is to develop a method for evaluating the sustainable performance of corporate boards using the balanced scorecard approach. Also, the paper aims to…
Abstract
Purpose
The purpose of this paper is to develop a method for evaluating the sustainable performance of corporate boards using the balanced scorecard approach. Also, the paper aims to determine the need and relevance of the proposed method in the evaluation process by testing the differences in the relative importance of the proposed method measures on a sample of the Egyptian manufacturing companies.
Design/methodology/approach
Data were collected using a questionnaire list and personal interviews with three different population samples: board members, managers of manufacturing companies and financial analysts in brokerage firms. The Wilcoxon signed rank test was used to test the degree of approval on the related questions, and the Kruskal–Wallis test was used to test the differences among the responses of the three samples.
Findings
The results of the statistical analysis indicate that there is a need for companies to have an effective tool to evaluate the board performance, and that the proposed method is a suitable tool for the evaluation. Also, the results indicate that there are differences in the relative importance of the performance measures among the three samples.
Research limitations/implications
The exploratory study focused on a sample of manufacturing companies only. Accordingly, service companies and financial institutions are outside the scope of this research. There was difficulty in accessing a sample of shareholders; instead, this sample was replaced by a group of financial analysts in brokerage firms.
Practical implications
The proposed method adds to the performance evaluation literature with regard to measuring and evaluating the performance of boards. The study provides an empirical evidence of the need to use the balanced scorecard in the board evaluation and its relevance for the evaluation process. It provides a short guide to the most important performance measures to be used in the evaluation process of the company’s board of directors.
Originality/value
Few studies have focused on evaluating the performance of the board of directors using the balanced scorecard. This study is an important attempt to evaluate the sustainable performance of the board of directors using the balanced scorecard by taking into consideration the corporate social responsibility perspective. The proposed board’s balanced scorecard provides a useful tool to evaluate the performance of boards using objective, specific and clear measures.