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Article
Publication date: 6 March 2024

Ahmed EL Hana, Ahmed Hader, Jaouad Ait Lahcen, Salma Moushi, Yassine Hariti, Iliass Tarras, Rachid Et Touizi and Yahia Boughaleb

The purpose of the paper is to conduct a numerical and experimental investigation into the properties of nanofluids containing spherical nanoparticles of random sizes flowing…

Abstract

Purpose

The purpose of the paper is to conduct a numerical and experimental investigation into the properties of nanofluids containing spherical nanoparticles of random sizes flowing through a porous medium. The study aims to understand how the thermophysical properties of the nanofluid are affected by factors such as nanoparticle volume fraction, permeability of the porous medium, and pore size. The paper provides insights into the behavior of nanofluids in complex environments and explores the impact of varying conditions on key properties such as thermal conductivity, density, viscosity, and specific heat. Ultimately, the research contributes to the broader understanding of nanofluid dynamics and has potential implications for engineering and industrial applications in porous media.

Design/methodology/approach

This paper investigates nanofluids with spherical nanoparticles in a porous medium, exploring thermal conductivity, density, specific heat, and dynamic viscosity. Studying three compositions, the analysis employs the classical Maxwell model and Koo and Kleinstreuer’s approach for thermal conductivity, considering particle shape and temperature effects. Density and specific heat are defined based on mass and volume ratios. Dynamic viscosity models, including Brinkman’s and Gherasim et al.'s, are discussed. Numerical simulations, implemented in Python using the Langevin model, yield results processed in Origin Pro. This research enhances understanding of nanofluid behavior, contributing valuable insights to porous media applications.

Findings

This study involves a numerical examination of nanofluid properties, featuring spherical nanoparticles of varying sizes suspended in a base fluid with known density, flowing through a porous medium. Experimental findings reveal a notable increase in thermal conductivity, density, and viscosity as the volume fraction of particles rises. Conversely, specific heat experiences a decrease with higher particle volume concentration.xD; xA; The influence of permeability and pore size on particle volume fraction variation is a key focus. Interestingly, while the permeability of the medium has a significant effect, it is observed that it increases with permeability. This underscores the role of the medium’s nature in altering the thermophysical properties of nanofluids.

Originality/value

This paper presents a novel numerical study on nanofluids with randomly sized spherical nanoparticles flowing in a porous medium. It explores the impact of porous medium properties on nanofluid thermophysical characteristics, emphasizing the significance of permeability and pore size. The inclusion of random nanoparticle sizes adds practical relevance. Contrasting trends are observed, where thermal conductivity, density, and viscosity increase with particle volume fraction, while specific heat decreases. These findings offer valuable insights for engineering applications, providing a deeper understanding of nanofluid behavior in porous environments and guiding the design of efficient systems in various industrial contexts.

Details

Multidiscipline Modeling in Materials and Structures, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 7 June 2013

Diwa Pandey, Mohammed H. Buzgeia, Epuru Suneetha, Hana Ahmed, Honida Abd El Rahaman Al Gani, Hajir Abd El Rahman Al Kadam and Nawal Juma Elariby

Breakfast skipping by children, with its varying global prevalence and associated factors, is well documented to adversely affect their health, cognitive ability, academic…

Abstract

Purpose

Breakfast skipping by children, with its varying global prevalence and associated factors, is well documented to adversely affect their health, cognitive ability, academic performance and anthropometric status. Libya, a country with a young population base, has limited information on breakfast skipping prevalence among its young citizens as well as its compounding factors unique to the country. The purpose of this paper is to investigate the breakfast skipping pattern among Benghazi primary school children.

Design/methodology/approach

The paper's approach is to use a cross sectional study among 386 primary school children (196 males and 190 females) using an interviewer‐administered structured questionnaire. The enrolment exclusion criteria were a pre‐existing chronic disease or a food allergy or food intolerance or any acute illness.

Findings

Breakfast skipping during weekdays (38.6 per cent, n=149), reduced drastically on weekends (1.0 per cent, n=4); 10.7 per cent subjects skipped breakfast daily (mean 2.5 + 1.3 days). Absence of hunger and lack of time to eat or prepare breakfast were cited as main barriers in its regular consumption. Bread and milk were the most commonly consumed breakfast foods. Certain groups of regular breakfast eating subjects consumed higher (p < 0.05) dietary thiamine and iron than their breakfast skipping counterparts and also better fulfilled their daily requirements for these nutrients. Parental breakfast eating habits influenced their children's breakfast eating pattern.

Practical implications

Efforts, including better time management, are required to inculcate a positive breakfast eating attitude among Benghazi primary school children. Their parents need to act as better role models by adopting healthy breakfast eating practices themselves.

Originality/value

The paper shows that breakfast skipping among Benghazi primary school children is a nutritional problem of grave concern, warranting a public health intervention.

Details

British Food Journal, vol. 115 no. 6
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 31 March 2020

Shakil Ahmed, Md. Mehrab Hossain and Iffat Haq

Construction management is enriched in many ways by direct and indirect support of lean construction concept. The objectives of this study are to assess the current level of…

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Abstract

Purpose

Construction management is enriched in many ways by direct and indirect support of lean construction concept. The objectives of this study are to assess the current level of awareness about lean construction practice, to identify the potential benefits and challenges to implement lean construction in the Bangladeshi construction industry and to prioritize them.

Design/methodology/approach

A comprehensive literature review has been done to design a questionnaire for the survey. The final questionnaire has been designed with 27 lean tools, 41 challenges, and seven benefits of implementing lean principles in the construction industry. A total of 164 valid responses have been collected from Bangladeshi construction practitioners involved in different types of construction organizations. The result has been analyzed by Relative Important Index (RII).

Findings

The findings revealed 41 challenges to implement lean construction with seven benefits in the Bangladeshi construction industry. The result shows that an appreciable number of respondent familiar with the techniques of lean construction but they don't practice. The findings have also pointed out that the lean construction approach adds a positive impact especially on quality, safety, cost, productivity, and environmental level. The top-ranked challenges to implementing lean construction are: lack of awareness and skill, poor management, traditional culture and attitude of employees, inadequate resources and equipment and nonuse of modern techniques and technologies.

Originality/value

This study reveals real scenario of lean construction in Bangladesh. It contributes to the body of knowledge, as it uncovers for the first time the awareness level, benefits and challenges to implement lean construction with reference to the social, economic and cultural context of Bangladesh. Exploring the findings, the study could help the stakeholders, construction firms, academician, researchers and government to focus their effort and resources on the significantly appropriate issues. Again, the study may be beneficial to developing countries especially in South Asia which share the same socio-economic status with Bangladesh.

Details

International Journal of Building Pathology and Adaptation, vol. 39 no. 2
Type: Research Article
ISSN: 2398-4708

Keywords

Article
Publication date: 24 May 2018

Hana Ajili and Abdelfettah Bouri

Shariah Board (SB) is considered as a typical corporate governance mechanism for the Islamic banking system. This board takes the responsibilities of assuring the compliance of…

1191

Abstract

Purpose

Shariah Board (SB) is considered as a typical corporate governance mechanism for the Islamic banking system. This board takes the responsibilities of assuring the compliance of transactions and operations with Islamic rules and principles. The purpose of this paper is to measure the SB quality and examine its moderating effect on the relationship between financial performance and accounting disclosure quality.

Design/methodology/approach

This study used a sample of 90 Islamic banks (IBs) during the period 2010-2014. The accounting disclosure quality and the SB quality were measured using self-developed indices. The moderating effect of the SB on the performance/disclosure relationship was examined using the hierarchical regression analysis.

Findings

The main finding of this study is related to the negative moderating effect of SB quality on the relationship between performance and disclosure. Accordingly, it can be said that the higher the quality of the SB is, the lesser the performance affects the disclosure. This result seems to indicate that at high level of SB quality, even when the performance decreases, the IBs engage in complying with accounting disclosure requirements in order to inform the stakeholders on the real situation of the bank.

Research limitations/implications

The finding of this study would be of great support to stakeholders and policy makers to make more pressure on IBs to improve the quality of their SB structure and show more compliance with the governance recommendations. As an extension to this study, further research can examine other Islamic governance mechanisms, such as the Internal Shariah Review.

Originality/value

To the authors’ knowledge, there has been a dearth of studies dealing with the empirical examination of the moderating impact of the SB quality on the association between the financial performance and the disclosure quality. Therefore, this study could be considered a tentative contribution to the literature by providing some empirical evidence on the links between these three variables using the moderation regression analysis.

Details

Managerial Finance, vol. 44 no. 5
Type: Research Article
ISSN: 0307-4358

Keywords

Article
Publication date: 2 October 2017

Hana Ajili and Abdelfettah Bouri

This study measures and compares the level of compliance with the disclosure requirements provided by the International Financial Reporting Standards (IFRS) and the Accounting and…

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Abstract

Purpose

This study measures and compares the level of compliance with the disclosure requirements provided by the International Financial Reporting Standards (IFRS) and the Accounting and Auditing Organization for Islamic Financial Institutions (AAOIFI). This study also aims to investigate the factors associated with this compliance in a sample of Islamic banks (IBs) in Gulf Cooperation Council member states.

Design/methodology/approach

The sample consists of 39 IBs between 2010 and 2014. Among the selected IBs, 23 banks were complying with the AAOIFI standards and 16 banks were complying with the IFRS standards. An unweighted disclosure index was used to measure the level of compliance with IFRS/AAOIFI disclosure requirements.

Findings

It was found that the level of compliance with IFRS is higher than that of compliance with AAOIFI. In addition, the results reveal that compliance with IFRS/AAOIFI disclosure requirements is higher for larger and older IBs. Finally, it was observed that compliance was more noticeable for IBs having a higher leverage and multinational subsidiaries.

Originality value

These findings would be of great help to regulators and policymakers to better understand the accounting disclosure practices of IBs.

Article
Publication date: 16 September 2020

Hana Salah-Salah

This paper aims to investigate the heritage management of the Algerian medinas subject to standardized safeguarding plans, referring only to the general community model, and then…

Abstract

Purpose

This paper aims to investigate the heritage management of the Algerian medinas subject to standardized safeguarding plans, referring only to the general community model, and then ignoring their particularities. Two medinas were selected as a case study: Annaba and Constantine.

Design/methodology/approach

Several methodologies of a descriptive historical issue and an exploratory study approach were used to determine the physical and cultural values of the two medinas. The objective is to see to what extent the medinas can be claimed as a place of affirmation and diffusion of urbanity.

Findings

On the basis of the results obtained, this work aims to articulate the tangible and intangible heritage as two inseparable dimensions to rethink the heritage of the Algerian medinas, taking into account the specificities and peculiarities of each of them.

Originality/value

This paper responds to an identified need to examine the issue of identity as a new approach that depends on the available characteristics of the historic center and the way in which planners and decision-makers use these resources as a guideline for implementing a new vision of safeguarding.

Details

Journal of Cultural Heritage Management and Sustainable Development, vol. 11 no. 3
Type: Research Article
ISSN: 2044-1266

Keywords

Article
Publication date: 16 September 2022

Muhammad Zaheer Asghar, Elena Barbera, Samma Faiz Rasool, Pirita Seitamaa-Hakkarainen and Hana Mohelská

This research paper aims to explore the influence of social media–based knowledge-sharing intentions (SMKI) on prospective authentic leadership development (ALD) to deal with the…

Abstract

Purpose

This research paper aims to explore the influence of social media–based knowledge-sharing intentions (SMKI) on prospective authentic leadership development (ALD) to deal with the future crisis. In the existing literature, to the best of the authors’ knowledge, there is no significant empirical evidence to test the relationship between SMKI and ALD. Thus, this study contributes to the growing literature regarding the role of SMKIs, ALD, social media–based knowledge-sharing behavior (SMKB) and facilitating conditions (FCs). However, in this study, the authors developed a conceptual framework based on technology adoption and leadership theory. It was used to identify preservice educational leaders’ SMKIs and their effect on ALD to deal with an educational crisis during the COVID-19 pandemic. Furthermore, SMKIs are strengthening ALD, directly and indirectly, using SMKB and FCs.

Design/methodology/approach

In this study, the higher education students are considered preservice leaders who were enrolled in educational leadership and management programs. However, this study’s target population and sample are students enrolled in educational leadership and management programs. Therefore, higher education students are considered preservice educational leaders. Therefore, a multilevel questionnaire survey approach was adopted to collect data from preservice educational leaders (n = 451 at Time 1 and n = 398 at Time 2) enrolled in education departments in the selected universities in Pakistan. A total of 398 survey questionnaires were finalized with a return ratio of 89%. The partial least square structural equation modeling with SmartPLS 3.2.8 was used for the data analysis.

Findings

This research found that SMKIs are positively and significantly connected with ALD. This study also confirms that SMKB significantly and positively mediates the relationship between SMKIs and ALD. Therefore, this study concludes that preservice educational leaders were ready to adopt SMKB.

Practical implications

Social media–based knowledge sharing can be helpful to develop authentic leadership among preservice educational leaders during a crisis. Preservice educational leaders as authentic leaders can prove to be an asset in dealing with the COVID-19 pandemic crisis.

Originality/value

This research integrated the technology adoption model and leadership theory to provide empirical evidence of SMKIs’ direct and indirect influence on ALD through social media–based knowledge-sharing actual use behavior by preservice educational leaders during the COVID-19 pandemic. Moreover, the moderated mediating effect of the FCs was also studied in the relationship between SMKIs and actual user behavior as well as ALD.

Article
Publication date: 10 August 2023

Ali Murad Syed, Hana Saeed Bawazir and Ibrahim Tawfeeq AlSidrah

The study aims to explore the relation between dividend policy of any company and its stock volatility.

Abstract

Purpose

The study aims to explore the relation between dividend policy of any company and its stock volatility.

Design/methodology/approach

Companies listed on six GCC stock markets are used in the analysis and the data ranges from 2006 to 2020. Fixed effect and random effect panel data analysis is used to explore the association between stock volatility and the dividend policies.

Findings

A significant negative relation is observed between dividend payout and stock volatility. Also, significant negative relation between stock volatility and equity is found, whereas insignificant positive relation is observed between asset growth and stock volatility.

Research limitations/implications

The data of all listed companies on six GCC markets were not available.

Practical implications

The question of raising dividend or maintaining at the current level is of utmost importance for the managers of any company before making any investment decisions. Also, the investors look at the dividend announcements as a sort of signal about the future prospect of the company. A stable or fluctuating dividends may be preferred by the investors that ultimately changes the stock price of any company.

Social implications

The relationship between dividend policy and the volatility of stock price is explored for emerging GCC markets which is the major significance of this paper which will have many social impacts on various stakeholders of any company including investors, regulators and employees, etc.

Originality/value

To the best of the authors’ knowledge, no study for GCC markets is done to establish a relation between stock volatility and the dividend policies which is needed by the academicians to further explore the behavior of these markets.

Details

Review of Accounting and Finance, vol. 22 no. 5
Type: Research Article
ISSN: 1475-7702

Keywords

Article
Publication date: 31 January 2020

Maher Dhahri and Hana Aouinet

The purpose of this study is to investigate air flow, temperature distribution and thermal confort in natural ventilation induced by solar chimney for different operating.

Abstract

Purpose

The purpose of this study is to investigate air flow, temperature distribution and thermal confort in natural ventilation induced by solar chimney for different operating.

Design/methodology/approach

Numerical simulation is performed using a commercial computational fluid dynamics (CFD) package ANSYS CFX software to understand the effects of air temperature, air velocity and solar heat flux on the performance of the solar chimney and thermal comfort. The comfort level was evaluated using the air diffusion performance index (ADPI) according to ASHRAE (55-210). The flow was investigated at inclination angles 45° solar heat flux 550-750 W/m2 and in a solar chimney of 1.4 m length, 0.6 m width and 0.20 m air gab.

Findings

The numerical results from the present simulation were first validated with experimental data, which was used for the thermal comfort indexes calculation. The obtained results of the analysis showed that the used numerical technique could accurately predict air flow and temperature distribution in natural ventilated building using solar chimney; the air temperature, air velocity and solar heat flux have a significant impact on thermal comfort; the temperature of 19°C with velocity of 0.15 m.s−1 gives the best effective draft temperature (EDT) satisfy ASHRAE (55-210) criteria that V = 0.35 m.s−1 and EDT range between −1.7 and 1.1.

Originality/value

In the present paper, air flow, temperature distribution and thermal comfort inside a room equipped with inclined solar chimney were numerically investigated and analyzed. The commercial CFD package (CFX 15) is used. Calculations are carried out in an empty room without any human or mechanical activity and the numerical results are compared with measurement points.

Details

World Journal of Engineering, vol. 17 no. 1
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 4 November 2020

Erny Rachmawati, Suliyanto and Agus Suroso

The purpose of this study is to determine the relationship between product knowledge and product involvement with purchase decision-making. In addition, this study also determines…

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Abstract

Purpose

The purpose of this study is to determine the relationship between product knowledge and product involvement with purchase decision-making. In addition, this study also determines the role of halal brand awareness as a moderating variable in influencing the relationship between product knowledge and product involvement with purchase decision-making.

Design/methodology/approach

Five major cities in Indonesia were chosen as study locations because they are student cities, and also cities with more population and more famous in Indonesia, so the sample is more heterogeneous. A total of 500 questionnaires were distributed using a convenience sampling method with an effective rate of 93%. Hypotheses are tested by structural equation modeling procedures using analysis of moment structure 22.0.

Findings

The empirical results suggest that product knowledge and product involvement have a positive and significant effect on consumer purchase decision-making; halal brand awareness is a moderating variable in the relationship between product knowledge and product involvement with purchase decision-making.

Research limitations/implications

This study adopts convenience sampling with the sampling area restricted in five cities, so it may not be suitable to be concluded as a consumer in general. This study only conducts research on halal food products in general. Future research may choose to use one brand of halal food product or compare several other halal food product brands. The results of the study support that the heterogeneity of respondents (age, education, gender and religion) has always been an important component in the study of consumption behavior. So that future research can examine the effect of different characteristics of respondents on the relationship between product knowledge, product involvement, halal brand awareness and purchase decisions.

Practical implications

The findings have significant implications that can help producers to develop strategies suitable for halal brand awareness and heighten the decision to purchase halal products by consumers in both Muslim and non-Muslim countries. So that the branding of halal products can enable businesses to access new markets for non-Muslim consumers in both Muslim and non-Muslim countries, so as to increase producer profitability by selling products at higher prices thereby providing higher profit margins.

Originality/value

In accordance with the author’s knowledge, this study is the first study to examine the moderator role of halal brand awareness variables in the relationship of product knowledge and product involvement with purchase decision-making.

Details

Journal of Islamic Marketing, vol. 13 no. 2
Type: Research Article
ISSN: 1759-0833

Keywords

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