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1 – 10 of 315Nawar Mohammed Ridha Hashim, Mohd. Zamri Yusoff and Hussein Ahmed Mohammed
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Research limitations/implications
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.
Originality/value
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.
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Ahmed Hussein Al-Rassas and Hasnah Kamardin
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Practical implications
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.
Social implications
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.
Originality/value
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.
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Harneel Acharya, Rakesh Reddy, Ahmed Hussein, Jaspreet Bagga and Timothy Pettit
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Research limitations/implications
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.
Practical implications
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.
Originality/value
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.
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Mushrek A. Mahdi and Ahmed Waleed Hussein
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…
Abstract
Purpose
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).
Design/methodology/approach
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.
Findings
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.
Originality/value
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.
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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…
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.
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Mustafa Abdel-samie Sadek, Jehan Ragab Daoud, Hussein Youssef Ahmed and Gamal Mohamed Mosaad
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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).
Originality/value
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.
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Ruhaila Md Kasmani, S. Sivasankaran, M. Bhuvaneswari and Ahmed Kadhim Hussein
The purpose of this study is to investigate the Soret and Dufour effects on the double-diffusive convective boundary layer flow of a nanofluid past a moving wedge in the…
Abstract
Purpose
The purpose of this study is to investigate the Soret and Dufour effects on the double-diffusive convective boundary layer flow of a nanofluid past a moving wedge in the presence of suction.
Design/methodology/approach
The similarity transformation is applied to convert the governing nonlinear partial differential equations into ordinary differential equations. Then, they are solved numerically by the fourth-order Runge–Kutta–Gill method along with the shooting technique and the Newton–Raphson method. In addition, the ordinary differential equations are also analytically solved by the homotopy analysis method.
Findings
The results for dimensionless velocity, temperature, solutal concentration and nanoparticle volume fraction profiles, as well as local skin friction coefficient and local Nusselt and local Sherwood numbers are presented through the plots for various combinations of pertinent parameters involved in the study. The heat transfer rate increases on increasing the Soret parameter and it decreases on increasing the Dufour parameter. The mass transfer behaves oppositely to heat transfer.
Practical implication
In engineering applications, a wedge is used to hold objects in place, such as engine parts in the gate valves. A gate valve is the valve that opens by lifting a wedge-shaped disc to control the timing and quantity of fluid flow into an engine.
Originality/value
No such investigation is available in literature, and therefore, the results obtained are novel.
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Hamdan Amer Al-Jaifi, Ahmed Hussein Al-rassas and Adel Ali AL-Qadasi
The purpose of this paper is to examine the impact of corporate governance strength on stock market liquidity in an emerging country, namely, Malaysia, by constructing a…
Abstract
Purpose
The purpose of this paper is to examine the impact of corporate governance strength on stock market liquidity in an emerging country, namely, Malaysia, by constructing a corporate governance score that captures both internal monitoring mechanisms (board of directors’ characteristics, audit committee’s characteristics and internal audit function) and external monitoring mechanism (audit quality).
Design/methodology/approach
The study uses a sample of 2,020 yearly firm observations in Bursa Malaysia over the period 2009-2012. The ordinary least square regression and several estimation methods such as two-stage least squares using instrumental variables (IV-2SLS) and dynamic GMM are employed.
Findings
This study finds a significant positive association between corporate governance effectiveness and stock market liquidity. The finding is robust to alternative liquidity measurements, to alternative estimation methods, and to endogeneity bias.
Research limitations/implications
This result implies that the firms with effective monitoring mechanisms mitigate information asymmetry which leads to less adverse selection problems among traders.
Practical implications
This study provides implications for regulators to help design regulations that enhance stock market liquidity. This study could also help investors and traders to formulate their trading decisions, and enables firms to know the importance of strengthening the corporate governance monitoring mechanisms.
Originality/value
This study constructs a corporate governance effectiveness measure by combining both internal and external monitoring mechanisms. These mechanisms have not been constructed together in one score in the corporate governance literature and the impact of internal audit function, as an internal monitoring mechanism on liquidity, has yet to be examined.
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The “war on terror” has nothing to do with protecting the U.S. and world's people from “terrorists”, and everything to do with securing the American empire abroad and…
Abstract
The “war on terror” has nothing to do with protecting the U.S. and world's people from “terrorists”, and everything to do with securing the American empire abroad and muzzling democracy and human rights at home. The 9-11 attacks were the pretext which sold the myth of evil Muslim terrorists imminently threatening Americans. That tale allowed the Cheney-led members of the Project for the New American Century (PNAC) to implement their 1990 DPG plan for world control. The “war on terror” is modelled on Islamophobic stereotypes, policies, and political structures developed by the Israeli Likkud and Bush Sr. in 1979. It is designed to inspire popular support for U.S. wars of world conquest. To defeat this plan, we must overcome our Islamophobic fear of “terrorists” and stand in solidarity with Muslims.
The main argument of this paper is that the accounting profession in Canada exercises hegemonic leadership over the development of tax education in terms of cadence and…
Abstract
The main argument of this paper is that the accounting profession in Canada exercises hegemonic leadership over the development of tax education in terms of cadence and direction of reforms. To support this argument, the paper uses the development of the microeconomic approach to teaching taxation and the correlation between the numbers of tax courses taught in undergraduate programs and exemptions provided by the provincial institutes of the Canadian Chartered Accountants to students joining them. It uses arguments from institutional isomorphism to elucidate expected resistance to adopting new developments, such as the microeconomic approach, in the accounting field. The paper also builds on Gramsci’s theory of hegemony to imply that business schools have given their consent to the Canadian Institute of Chartered Accountants by closely linking their curriculum, at least the taxation courses, to that of the institute.
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