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The purpose of this paper is to numerically study the phenomenon of separation and subsequent reattachment that happens due to a sudden contraction or expansion in flow geometry, in addition, to investigating the effect of nanoparticles suspended in water on heat transfer enhancement and fluid flow characteristics.

Turbulent forced convection flow over triple forward facing step (FFS) in a duct is numerically studied by using different types of nanofluids. Finite volume method is employed to carry out the numerical investigations. with nanoparticles volume fraction in the range of 1-4 per cent and nanoparticles diameter in the range 30-75 nm, suspended in water. Several parameters were studied, such as the geometrical specification (different step heights), boundary conditions (different Reynolds [Re] numbers), types of fluids (base fluid with different types of nanoparticles), nanoparticle concentration (different volume fractions) and nanoparticle size.

The numerical results indicate that the Nusselt number increases as the volume fraction increases, but it decreases as the diameter of the nanoparticles of nanofluids increases. The turbulent kinetic energy and its dissipation rate increase as Re number increases. The velocity magnitude increases as the density of nanofluids decreases. No significant effect of increasing the three steps heights on Nusselt along the heated wall, except in front of first step where increasing the first step height leads to an increase in the recirculation zone size adjacent to it.

The phenomenon of separation and subsequent reattachment happened due to a sudden contraction or expansion in flow geometry, such as forward facing and backward facing steps, respectively, can be recognized in many engineering applications where heat transfer enhancement is required. Some examples include cooling systems for electronic equipment, heat exchanger, diffusers and chemical process. Understanding the concept of these devices is very important from the engineering point of view.

Convective heat transfer can be enhanced passively by changing flow geometry, boundary conditions, the traditional fluids or by enhancing thermal conductivity of the fluid. Great attention has been paid to increase the thermal conductivity of base fluid by suspending nano-, micro- or larger-sized particles in fluid. The products from suspending these particles in the base fluid are called nanofluids. Many studies have been conducted to investigate the heat transfer and fluid flow characteristics over FFS. This study is the first where nanofluids are employed as working fluids for flow over triple FFS.

The purpose of this study is to examine the effect of the audit committee (AC) independence, financial expertise, internal audit function, audit quality and ownership concentration on earnings quality (EQ) and, consequently, ascertain whether the AC’s independence and financial expertise has a moderating effect on the relationship between internal audit function and EQ.

The study sample is 508 firms listed on the Main Market of Bursa Malaysia (formerly known as Kuala Lumpur Stock Exchange) for the years 2009 to 2012. EQ was measured using two modified Jones models of discretionary accruals.

The findings reveal that the independence of AC and investment in internal audit function, as well as the Big4 audit firm, are related to greater EQ. Ownership concentration is found to be associated with lower EQ. The study provides evidence that AC’s independence moderates the relationship between internal audit function (investment in and sourcing arrangements of internal audit function) and EQ. It also shows that AC’s financial expertise moderates the relationship between sourcing arrangements of internal audit function and EQ.

This study extends the prior related literature by examining the AC’s independence and financial expertise as moderating variables on the relationship between internal audit function and EQ.

Policymakers might use the findings regarding EQ in relation to governance practices, to recognize the important roles played by the AC’s independence and financial expertise on the effectiveness of internal audit function with EQ.

This study uses the agency theory and resource dependence theory to provide empirical evidence on the impact of internal audit function and AC on EQ in the ownership concentration environment.

The purpose of this paper is to evaluate the effectiveness of role playing as an applied learning technique for enhanced classroom experiences as compared to traditional lecture methods.

This study uses the pre-test/post-test design to conduct experiments with several control and experimental groups. Subjects are graduate students in an MBA program at a private, non-profit university in a traditional classroom setting.

Students in the experimental group gained significantly more knowledge (post-test minus pre-test scores) – 45 percent higher – through participation in the role playing exercise as compared to the control group.

This study represents only a single educational discipline explored using a single role playing learning activity. Impacts on the long-term retention of the knowledge should be studied further.

Educators should enhance their classroom experience with more applied learning activities such as role playing in order to increase knowledge gain and potentially longer knowledge retention.

This study uses a customized role playing activity within a business curriculum as one of many applied learning techniques. The value to students was shown by significantly higher gain in knowledge while simultaneously enhancing their enjoyment of the classroom experience to potentially encourage further lifelong learning.

The purpose of this paper is to investigate the combined effect of wear and turbulence on the performance of a hydrodynamic journal bearing operating under Newtonian and couple stress fluids (CSF).

The analysis consists of a modified Reynolds equation of incompressible thin viscous films, and the film thickness model taking into account the wear effect. The governing equation was solved numerically using the finite difference approach.

The effect of both the wear parameter and the local Reynolds number on the performance characteristics of bearing has been presented and discussed. The obtained results observed that the characteristics of the intact and worn bearing in turbulent and laminar have been enhanced due to the non-Newtonian fluid (CSF) effect. Also, the results display that bearing worn and the turbulent regime cannot be neglected in calculating the performance characteristics of the bearing lubricated with Newtonian and non-Newtonian fluids. The results achieved from this study, specify that the bearing characteristics are significantly affected by these effects.

The paper investigates the behavior of hydrodynamic bearings considering different aspects simultaneously is interesting, and the application meets the current needs of improvement in modeling hydrodynamic bearings under different conditions.

The purpose of the study is to obtain explicit formulas to determine the stability of periodic solutions to the new system and study the extent of the stability of those periodic solutions and the direction of bifurcated periodic solutions. More than that, the authors did a numerical simulation to confirm the results that the authors obtained and presented through numerical analysis are the periodic and stable solutions and when the system returns again to the state of out of control.

The authors studied local bifurcation and verified its occurrence after choosing the delay as a parameter of control in Zhou 2019’s dynamical system with delayed feedback control. The authors investigated the normal form theory and the center manifold theorem.

The occurrence of local Hopf bifurcations at the Zhou's system is verified. By using the normal form theory and the center manifold theorem, the authors obtain the explicit formulas for determining the stability and direction of bifurcated periodic solutions. The theoretical results obtained and the corresponding numerical simulations showed that the chaos phenomenon in the Zhou's system can be controlled using a method of time-delay auto-synchronization.

As the delay increases further, the numerical simulations show that the periodic solution disappears, and the chaos attractor appears again. The obtained results can also be applied to the control and anti-control of chaos phenomena of system (1). There are still abundant and complex dynamical behaviors, and the topological structure of the new system should be completely and thoroughly investigated and exploited.

Adopting new technologies to improve supply chain activities and processes is essential due to increasingly complex and dynamic business environments. Particularly in the pharmaceutical industry, high-quality standards must be met, requiring transparency and visibility in the supply chain. This research aims at investigating the implementation of blockchain technology in the supply chain of an Egyptian pharmaceutical company.

The research applies a single case-study approach building on the theoretical underpinnings of transaction cost economics. Twenty-five semistructured interviews were conducted with pharmacies and employees of the case company to identify the blockchain technologies' potential for pharmaceutical supply in Egypt. Further analyzing the frequencies of the codes, the authors elaborate on specific relationships between the observed practices.

The research revealed the potential benefits of adopting blockchain technology. Transaction costs are indeed positively impacted by reduced contracting costs, processing costs and lead times, also ensuring the safe delivery of medications. However, the findings also highlight obstacles related to running costs, awareness and company culture. Regarding supply chain governance, blockchain technology can enhance collaboration within the supply chain as well as with important stakeholders.

Insufficient management of pharmaceutical supply chains (PSC) may affect a company's reputation but also disrupt the patient's healing process due to temperature damage and counterfeit medicines. Blockchain governance, in this vein, can ensure a safer and more reliable supply of pharmaceutical products. For intraorganizational purposes, however, cloud solutions, barcoding and generally digital platforms are rated more frequently than blockchain solutions.

The present study contributes to an advanced understanding how blockchain technology supports PSC, particularly in an emerging country context like Egypt. It thereby confirms and extends previous research as well as adds to the theoretical underpinnings of digitalized supply chains.

This paper aims to examine the mediating role of big data adoption (BDA) on the association between board governance (BG) and audit report lag (ARL).

This study uses data extracted from financial reports for a sample from EGX100 over the period from 2015 to 2019. This study applies content analysis approach to measure the level of BDA. This study uses ordinary least squares, structure equation modelling and principal component analysis to investigate the relationship between BG, BDA and ARL.

The findings indicate that BDA can be used as a predictor of ARL for companies listed on the Egyptian stock exchange. The results show that board diversity has a significant effect on ARL when BDA is used as a mediator.

This study only includes technology, telecommunications and health-care industries in the sample.

This paper raises investor and stakeholder awareness for the importance of BDA and corporate governance (CG) procedures in reducing audit report delays in developing countries such as Egypt. This study can assist regulators in developing audit report requirements and enforcing regulations to guarantee timely audit report publication.

This paper provides a shred of unique evidence on the role of BDA in mediating the relationship between BG and ARL in a developing country.

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.

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.

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.

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.

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.

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.

The purpose of this study is to address a problem in cooling of an electronic package where the dissipating fins transfer the extra heat energy from the heat source (i.e. electronic devices) to the heat sink (i.e. environment). To this end, the convective heat transfer of nanofluid flow over dissipating fins is simulated using a numerical approach, whereas the properties of nanofluid are evaluated based on the experimental measurements and used in the numerical process.

To simulate the convective flow, the lattice Boltzmann method is used. Also, the curved boundary scheme is used to enhance the capability of lattice Boltzmann method (LBM) in the simulation of natural convection in curved boundaries. In addition, the second law analysis is used based on total and local approaches.

To improve the cooling performance of fins, a modern technique is used, which is using of nanofluid. For this purpose, samples of SiO₂-liquid paraffin with mass fractions of 0.01, 0.05, 0.1, 0.5 and 1 (Wt.%) in a temperature range of 25–60 °C are provided, and the required thermal and physical properties of samples including thermal conductivity and dynamic viscosity are measured during experimental work. The extracted results are used in the numerical simulations using derived correlations.

The originality of the present work is using a modern numerical method in the investigation of an engineering application and combining it with experimental data.

This study aims to investigate the nutrient composition and cholesterol content of most popular fast foods sold in Qena city, Egypt with reference to their trans fatty acids contents.

Total 80 samples of fast foods were collected from various fast food restaurants in Qena city, Egypt. The samples were investigated for their nutritive quality by measuring moisture, protein, fat, ash, carbohydrate and energy content as described by the association of analytical chemists. The cholesterol content was determined using a spectrophotometer, while trans fatty acids were analyzed by gas chromatography using standard methods.

The study revealed a wide variation in the composition and nutritive value. On a fresh weight basis, moisture, protein, fat, carbohydrate and ash ranged from 45.9-55.0 (P < 0.001), 15.0-22.3 (P < 0.001), 13.1-15.7 (P = 0.034), 6.0-16.2 (P < 0.001) and 2.2-3.5 (P < 0.001), %w/w, respectively. The fast foods were very energy dense with calorie content varying from 236.5-281.1 (P < 0.001), Kcal/100 g. The mean values of cholesterol were between 15-17 mg/100 g (P = 0.398). The findings showed that fast foods had high total trans fatty acids content exceeding the Danish legal limit of 2 g/100 g of fat being in the range of 3.5 to 11.3 g per 100 g fat (P = 0.379). Elaidic acid is the predominant trans-isomer in industrially produced trans fatty acids. The concentrations of elaidic acid were high in all samples examined (P = 0.942).

This study has established the fact that fast foods are associated with high total energy intake, high intake of fat, trans fat and a higher proportion of calories being derived from total fat and trans-fat. Therefore, it is recommended to limit the intake of fast food.