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The fiber orientation is considered one of the important parameters that have an effect on the characteristics of composites. This paper aims to investigate the effect of fiber orientation on the abrasive wear of the glass-epoxy (G-E) composites with different silicon carbide (SiC) filler weights (Wt.%).

The wear rate of glass fiber reinforced with angle-ply 0º, ±45º and 90º is discussed. The G-E composites with different weights of SiC filler at angle ±45º are considered. Hand lay-up technique was adopted for specimen preparation. The influence of effective parameters such as filler Wt. %, normal load, abrasive size and abrading distance on the wear rate was presented and discussed.

Experimental tests including pin on disk, micro-hardness and scanning electron microscope were carried out to investigate the composite characteristics.

The experimental results showed that the resistance wear was superior in case of ±45º fiber orientations. A validation of the experimental results using Taguchi approach to verify the optimal wear rate parameters was presented.

This study aims to illustrate the impacts of the motion of circular cylinders on the natural convection flow from variable heated partitions inside the X-shaped cavity filled with Al₂O₃-water nanofluid. A partial layer of a homogeneous/heterogeneous porous medium is located in the top area of the X-shaped cavity.

Three different cases of the porous media including homogeneous, horizontal heterogeneous and vertical heterogeneous porous media were considered. Three different thermal conditions of the embedded circular cylinders including hot, cold and adiabatic conditions are investigated. An incompressible scheme of smoothed particle hydrodynamics (ISPH) method is modified to compute the non-linear partial differential equations of the current problem. Two variable lengths of the left and right sides of the X-shaped cavity have a high-temperature T_h and a low-temperature T_c, respectively. The other wall parts are adiabatic. The numerical simulations are elucidating the dependence of the heat transfer and fluid flow characteristics on lengths of hot/cold source L_h, porous cases, Darcy parameter, thermal conditions of the embedded circular cylinders and solid volume fraction.

Overall, an increment in length of hot/cold source leads to augmentation on the temperature distributions and flow intensity inside the X-shaped cavity. The hot thermal condition of the circular cylinder augments the temperature distributions. The homogeneous porous medium slows down the flow speed in the top porous layer of the X-shaped cavity. The average Nusselt number decreases as L_h increases.

ISPH method simulated the motion of circular cylinders in the X-shaped cavity. The X-shaped cavity is saturated with a partial layer porous medium. It is found that an increase in hot source length augments the temperature and fluid flow. ISPH method can easily handle the motion of cylinders in the X-shaped cavity. Different thermal conditions of cylinders can change the temperature distributions in X-cavity.

The purpose of this study is to use an incompressible smoothed particle hydrodynamics (ISPH) method for simulating buoyancy ratio and magnetic field effects on double diffusive natural convection of a cooper-water nanofluid in a cavity. An open pipe is embedded inside the center of a cavity, and it is occupied by solid particles.

The dimensionless governing equations in Lagrangian form were solved by ISPH method. Two different thermal conditions were considered for the solid particles. The actions of the solid particles were tracked inside a cavity. The effects of Hartman parameter, Rayleigh number, nanoparticles volume fraction and Lewis number on features of heat and mass transfer and flow field were tested.

The results showed that the buoyancy ratio changes the directions of the solid particles diffusion in a cavity. The hot solid particles were raised upwards at aiding mode (N > 0) and downwards at an opposing mode (N < 0). A comparison is made with experimental and numerical simulation results, and it showed a well agreement.

Novel studies for the impacts of buoyancy ratio on the diffusion of solid particles embedded in an open pipe during double-diffusive flow were conducted.

The purpose of this study is to examine the impact of firm financial and operational characteristics on the level of forward-looking information disclosure (FLID) by Egyptian-listed non-financial companies. The present research also aims to investigate the moderating role of gender diversity on the board of directors.

The sample incorporates the non-financial companies included in the EGX 100 of the Egyptian Stock Exchange (ESE), whose reports were available during the study period from 2013 to 2018. The final sample comprises 49 companies with 294 observations. Statistical analysis is performed using multiple regression analysis.

This study found a significant positive impact of return on assets, leverage, company size and age on the level FLID, while external audit firm type and industry were found to impact the level of FLID negatively. Further, the board gender diversity (BGD) is found to have a moderating impact as it strengthens the effect of financial and operational characteristics on the level of FLID.

The present study has some implications for Egyptian companies, investors in the Egyptian market and regulators in emerging economies, which include paying more attention to BGD when selecting the board members by companies as well as following up the female representation in all the listed companies by regulators.

To the best of the authors’ knowledge, this is the first study to investigate the moderating role of BGD and its impact on the level of FLID in emerging markets. This extends the disclosure literature as the present study brings new evidence from an emerging market regarding BGD moderating role as early research concentrated on the direct impact of BGD on the level of FLID.

The purpose of this paper is to shed light on the relationship between the Internet Financial Reporting (IFR) levels and corporate characteristics. It is assumed that the relationship between the disclosure level and its determinants is known. Nevertheless, the results of the empirical studies confirm that it is a naive assumption. As a result, the author suggests refusing the conventional methods of econometric analysis.

The research methodology consisted of four stages: First, the author tried to select the “best” model using the Akaike Information Criterion (AIC). Second, the author checked out the stability of the relationship between corporate disclosure level and its determinants. Third, the regression analysis was used. Finally, the author proposed a “genetic-fuzzy system” for studying the determinants of corporate disclosure. The firms' yearly data collected consisted of a random sample of 152 Tunisian companies' websites.

The results show that the variables that should be used to explain the level of IFR are firm size, ownership concentration, firm performance and liquidity. The Chow forecast test shows that there is a significant and large difference between the actual and the predicted values. Consequently, the author suggests using non-parametric methods, particularly a methodology based on fuzzy logic concepts and genetic algorithms. This technique would allow the author to discover the true form of the relationship between the disclosure level and its determinants. Regarding the hypotheses of this study, the findings of the “genetic-fuzzy system” validate all the hypotheses. Indeed, the arguments of the agency theory, the signaling theory, and the political cost hypothesis were supported using the “genetic-fuzzy system.”

The originality of the paper lies in providing a new research methodology based on several statistical tools for dealing with an important research topic in accounting and finance, i.e. the determinants of IFR. The results of this study can be considered as a starting point to develop a unified methodology.

The purpose of this paper is to investigate the impact of board structure on voluntary corporate disclosure via social media among the top 150 companies listed on the London Stock Exchange.

A disclosure index comprising of a set of items that encompass two facets of disclosure, namely corporate disclosure via social networks and social media sites, is developed and used. Binary logistic regression is used to test the research hypotheses.

The results of this study reveal the underlying relations between board composition and control variables as the determining factors of corporate disclosure, i.e. board size, board activism, board independence and board diversity (gender and ethnicity). The gender of the board can affect the corporate disclosure via a social network. The results of this study indicate that an increase in the number of female in the board members leads to higher corporate disclosure using social network. Moreover, firm size has a positive effect on corporate disclosure indicating that large firms tend to disclose more information on their websites and social networks.

The paper provides new insights into the role played by the non-executive female directors in monitoring and controlling managerial processes related to corporate disclosure using social media.

To the best of the authors’ knowledge, this is the first paper that examines the role of board structure in monitoring and controlling management decisions and managerial processes in the area of corporate disclosure via social media.

This study aims to examine the relationship between financial report readability (FRR) and audit fees (AF) by bringing evidence from an emerging market. In addition, it reveals the moderating influence of board gender diversity (BGD) on such a relationship.

The authors analyzed data collected manually from the financial reports of Egyptian nonfinancial firms listed on the Egyptian Stock Exchange between 2016 and 2021 using Pooled OLS, Random effects, Fixed effects regressions.

The authors found a negative relationship between FRR and AF. Likewise, BGD is found to be negatively related to AF, and positively associated with FRR. In addition, the authors found that the negative association between FRR and AF is more pronounced in the case of BGD.

This paper contributes to previous research on the auditors’ reactions to the clarity of financial reporting as well as the role of board gender concerning the FRR-audit pricing relationship in emerging markets.

Purpose – The purpose of this article is to examine the Internet financial reporting (IFR) practice by listed companies in Egypt as one of the emerging markets (EMs) and investigate empirically some company characteristics as determinants of such practice.

Methodology/approach – Using a 39-item index, content analysis of websites was performed for 88 of the most active Egyptian listed companies on the Egyptian Stock Exchange (EGX). Further, the article employs statistical analysis to test the association between six company characteristics (independent variables) and the extent of the IFR (including three dependent variables).

Findings – Among the sampled companies, only 57 have accessible websites and 45 provide financial information in their websites. The results of univariate analysis, which were verified by multivariate linear regression, show that some company characteristics (e.g. size, profitability, foreign listing and ownership structure) are significantly positively associated with the IFR, while legal form is significantly negatively associated.

Research limitations and implications – The scope of this study is limited to a relatively small sample of Egyptian listed companies and they may not represent all of the possible listed companies. It would be interesting to duplicate this study in other EM countries which have many similarities to the Egyptian environment.

Originality/value – This investigation concerned a country with an EM – Egypt. Few articles have provided insight into the IFR practices of listed companies in Egypt as one of the EM. Unlike previous studies conducted in Egypt, the current study provides evidence regarding two company characteristics, for the first time in Egypt, namely ‘ownership structure’ and ‘legal form’ as explanatory variables of the extent of IFR by listed companies in EGX.

This study aims to investigate the influence of corporate governance (CG) on environmental disclosure (ED) practices within UK and US firms, addressing the contemporary challenges confronting firms in both contexts.

Using the dynamic panel regression framework of system generalised method of moment (GMM), this study analyses a sample comprising 121 FTSE and 200 S&P firms from 2010 to 2020.

The findings emphasise the dynamic nature of ED practices among UK and US firms, demonstrating their propensity to swiftly adjust to desired levels whenever deviations occur. Besides, this study identifies board independence and the frequency of board meetings as significant determinants of ED for UK firms. In contrast, for US firms, board independence and audit committee independence are found to be significant determinants of ED.

The research highlights the fundamental role played by CG in shaping how firms in the UK and the US navigate agency problems and respond to diverse stakeholder demands through ED in their annual reports. This study advocates for the promotion of robust governance systems that concurrently serve the purposes of accountability and monitoring to bridge the information expectation gap between firms and stakeholders. The findings reinforce the necessity for regulatory initiatives involving policy formulation and corporate oversight to enhance private sector awareness regarding environmental reporting practices.

This study contributes to the scarce literature on the impact of board and audit committee characteristics on ED practices in the UK and US contexts. In addition, by using the system GMM estimation technique, this study provides robust and updated evidence that addresses the weaknesses inherent in previous studies.

The entropy and thermal behavior analyses of non-Newtonian nanofluid double-diffusive natural convection inside complex domains may captivate a bunch of scholars’ attention because of the potential utilizations that they possess in modern industries, for example, heat exchangers, solar energy collectors and cooling of electronic apparatuses. This study aims to investigate the second law and thermal behavior of non-Newtonian double-diffusive natural convection (DDNC) of Al₂O₃-H₂O nanofluid within a C-shaped cavity emplacing two hot baffles and impacted by a magnetic field.

For the governing equations of the complicated and practical system with all considered parameters to be solved via a formidable numerical approach, the finite element method acts as an approach to achieving the desired solution. This method allows us to gain a detailed solution to the studied geometry.

This investigation has been executed for the considered parameters of range, such as power-law index, baffle length, Lewis number, buoyancy ratio, Hartmann number and Rayleigh number. The main results reveal that isothermal and concentration lines are significantly more distorted, indicating intensified concentration and temperature distributions because of the growth of baffle length (L). Nu_ave decreases by 8.4% and 0.8% while it enhances by 49.86% and 33.87%, respectively, because of growth in the L from 0.1 to 0.2 and 0.2 to 0.3.

Such a comprehensive study on the second law and thermal behavior of DDNC of Al₂O₃-H₂O nanofluid within a C-shaped cavity emplacing two hot baffles and impacted by magnetic field has not yet been carried out.