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Presents the findings of an investigation into the attitudes of civil engineers and their companies towards modern management practices. Contractors are moving rapidly to meet the challenges of a modern business world and are making full use of the tools available. Consultants, however, are lagging behind in their attitudes and are slower in embracing the theories and practices involved. The investigation has raised as many questions as have been answered but sufficient information has been provided to make the reader think seriously about the subject of management, and the training of managers within the construction industry.

Reviews the general state of computer systems in the construction industry. Reports on a survey aimed at examining the attitudes of people in the construction industry regarding computer applications and reveals the importance of computers in areas such as engineering and management. Highlights the prospects of computer applications in the future and concludes that advances in technology are going to require a change in attitude between all parties in the industry.

The purpose of this paper is to examine numerically the magnetohydrodynamic (MHD) free convection and thermal radiation heat transfer of single walled carbon nanotubes-water nanofluid within T-inverted shaped corrugated cavity comprising porous media including uniform heat source/sink for solar energy power plants applications.

The two-dimensional numerical simulation is performed by drawing on Comsol Multiphysics program, based on the finite element process.

The important results obtained show that increasing numbers of Rayleigh and Darcy and the parameter of radiation enhance the flow of convection heat. Furthermore, by increasing the corrugation height, the convection flow increases, but it decreases with the multiplication of the corrugation height. The use of a flat cavity provides better output than a corrugated cavity.

The role of surface corrugation parameters on the efficiency of free convection and heat transfer of thermal radiation within the porous media containing the T-inverted corrugated cavity including uniform heat source/sink under the impact of Lorentz forces has never been explored. A contrast is also established between a flat cavity and a corrugated one.

The purpose of this paper is to investigate the enhancement of the performance of bubble absorber using hybrid nanofluid as a cooled NH₃/H₂O absorption system to reduce their size and to find the best fitting model. A numerical model for ammonia-water bubble absorber was developed to show the influence of operating conditions and design parameters on the absorber performance.

A finite difference numerical method is used to solve the numerical model. The model is subjected to the inlet conditions of liquid, vapor and coolant flow regimes. The absorber modeling was divided into small elements along the absorber length.

The model proposed is validated with previously published works. Then agreement between the both is considered as good.

Numerical results/The use of hybrid nanofluids.

The results showed that the hybrid nanofluid is the best cooling medium. Very high heat transfer rates are obtained because of the high thermal conductivity and specific heat of hybrid nanofluid, and consequently, the absorber size decreases. It was also found that the absorber thermal load and the mass absorption flux increase with increasing of solid volume fraction. Also, the existence of an optimal absorber length was revealed, required for complete absorption when using hybrid nanofluid as a cooling medium. It is recommended that using hybrid nanofluid to remove the heat from the absorber is the best candidate for NH₃/H₂O absorption performance enhancement.

The purpose of this paper is to examine the effect of corporate governance structure and CEO compensation on the level of tax aggressiveness.

This work analyzes a sample of 471 observations of 100 companies listed on the NASDAQ 100 for the period 2008-2012. It uses a fixed-effect panel model to analyze the effect of different model variables on the tax aggressiveness level.

The main finding of this study is the great influence of corporate governance structure and CEO compensation on reducing tax aggressiveness. Indeed, it finds a significant negative relation between board size, CEO salary, CEO stock options and tax aggressiveness. In addition, the study reveals that there is a direct negative relation between CEO duality, tax fees and tax aggressiveness.

The study was conducted using robust methods to test the effect of corporate governance structure and CEO compensation on tax aggressiveness level. The generalized least squares method was used to fit panel data and overcome heteroscedasticity and autocorrelation problems. The aim of the study was to prove the great effect of both corporate governance structure and CEO compensation on reducing tax aggressiveness. As this study was based on data from American companies, the results cannot be generalized to all contexts.

This paper differs from previous work and tests the effect of corporate governance structure, CEO compensation, CEO characteristics and audit fees on tax aggressiveness. The findings of this study will enrich the literature on tax aggressiveness by suggesting that corporate governance structure and CEO compensation can significantly limit tax aggressiveness behavior. Therefore, shareholders must be aware of these two variables. They need to limit tax aggressiveness behavior, as it is usually accompanied by rent diversion, as reported by Desai and Dharmapala (2006). Therefore, these findings will be helpful to investors, managers and regulators because they have implications for the interactive decision-making process.

This paper aims to investigate the economic, political or sociocultural determinants of corruption in Tunisia.

To better understand the main determinants of corruption in Tunisia. This study uses The Bayesian Model Averaging (BMA) model, which allows us to include a large number of explanatory variables and for a shorter period.

The results show that economic freedom is the most important variable of corruption in Tunisia. In second place comes the subsidies granted by the government, which is one of the best shelters of corruption in Tunisia through their use for purposes different from those already allocated to them. Third, this paper finds the high unemployment rate, which, in turn, is getting worse even nowadays. The other three factors considered as causal but of lesser importance are public expenditures, the human development index (HDI) and education. Education, the HDI and the unemployment rate are all socio-economic factors that promote corruption.

The realization of this study will lead to triple net contributions. The first is to introduce explicitly and simultaneously political, social and economic determinants of corruption in developing countries. Second, unlike previous studies based on the simple and generalized regression model, the present research uses another novel and highly developed estimation method. More precisely, this study uses the BMA model, on the set of annual data for a period of 1998–2018. The third contribution of this research resides in the choice of the sample.

This study investigates the impact of three parameters such as: number of LED chips, pitch and LED power on the junction temperature of LEDs using a best heat sink configuration selected according to a lower temperature. This study provides valuable insights into how to design LED arrays with lower junction temperatures.

To determine the best configuration of a heat sink, a numerical study was conducted in Comsol Multiphysics on 10 different configurations. The configuration with the lowest junction temperature was selected for further analysis. The number of LED chips, pitch and LED power were then varied to determine the optimal configuration for this heat sink. A general equation for the average LED temperature as a function of these three factors was derived using Minitab software.

Among 10 configurations of the rectangular heat sink, we deduce that the best configuration corresponds to the first design having 1 mm of width, 0.5 mm of height and 45 mm of length. The average temperature for this design is 50.5 C. For the power of LED equal to 50 W–200 W, the average temperature of this LED drops when the number of LED chips reduces and the pitch size decreases. Indeed, the best array-LED corresponds to 64 LED chips and a pitch size of 0.5 mm. In addition, a generalization equation for average temperature is determined as a function of the number of LED chips, pitch and power of LED which are key factors for reducing the Junction temperature.

The study is original in its focus on three factors that have not been studied together in previous research. A numerical simulation method is used to investigate the impact of the three factors, which is more accurate and reliable than experimental methods. The study considers a wide range of values for the three factors, which allows for a more comprehensive understanding of their impact. It derives a general equation for the average temperature of the LED, which can be used to design LED arrays with desired junction temperatures.

The purpose of this paper is to examine the motivations of earnings management and financial aggressiveness levels in the big 100 companies listed on the NASDAQ 100 after the 2007 financial crisis.

This paper uses two samples. The first contains 471 observations of 100 companies listed on the NASDAQ 100 for the period 2008-2012 and is used to examine the motivations of earnings management. The second represents 282 observations of companies listed on the NASDAQ 100 that use financial aggressiveness. The authors use a panel data model to analyze the effects of four explanatory variables (corporate governance structure, CEO compensation, CEO characteristics and audit fees) on both earnings management and financial aggressiveness levels.

The results of the investigation show the significant impact of corporate governance structure, CEO compensation, CEO characteristics and audit fees on reducing the earnings management and financial aggressiveness levels.

The findings can be valuable to both investors and researchers. For researchers, the present work may help in explaining the motivations of earnings management and financial aggressiveness practices used by large American firms after the 2007 US financial crisis. For investors, this study serves to highlight the critical importance of corporate governance, CEO compensation and CEO characteristics in limiting such behaviors. Thus, investors are recommended to account for such variables in order to make effective investment decisions. As an extension to this study, researchers might consider other CEO psychological variables. Other market indices could also be considered in order to generalize and validate the results of the research.

Investors must take into consideration the corporate governance structure and ask for supplementary information about CEO characteristics to ensure better investment decisions.

In this paper, and in contrast to previous research, the authors test the impact of corporate governance structure, CEO compensation, CEO characteristics and audit fees together on the level of both earnings management and financial aggressiveness behavior for large US non-financial firms after the 2007 financial crisis. The authors show that older CEOs use less earnings management and financial aggressiveness. The findings can be valuable to investors, managers and regulators because they have implications for their interactive decision-making process.

The purpose of this paper is to study the natural convection and radiation heat transfer inside Nonagon inclined cavity with variable heated source length, which contains a porous medium saturated with nanofluid in the presence of uniform heat generation or absorption under the effect of uniform magnetic field with variable direction. The shape factor of nano particles is taking account for the model of nanofluid.

This study is established in two-dimensional space. The 2D numerical study is effectuated with Comsol Multiphysics based on the on the finite element method. The 2D equation system is exposed on dimensionless form taking into account the boundary conditions.

Results obtained show that the convection heat transfer is ameliorated with the augmentation of heated source length. The convection heat transfer is enhanced by increasing Rayleigh, Darcy numbers and the heated source length; however, it is reduced by rising Hartmann number. The presence of radiation parameter lead to improve the convection heat transfer in the presence of both uniform heat generation/absorption. The average Nusselt number reaches a maximum for an inclination of cavity γ = 45° and a minimum for γ = 60°. Both the increase of the shape factor of nano particles and the solid fraction of nano particles improve the convection heat transfer.

Different studies have been realized to study the heat transfer inside cavity contains porous medium saturated with nanofluid under magnetic field effect. In this work, the Nonagon geometric of cavity studied has never been studied. In addition, the effect of radiation parameter with relation of the shape factor of nanoparticles in the presence of uniform heat generation/absorption on the heat transfer performance have never been investigated. Also, the effect of magnetic field direction with relation of the inclination cavity on heat transfer performance.

This study seeks to build a financial uncertainty index for Saudi Arabia. This index serves as a leading indicator of Saudi economic activity and helps to describe economic fluctuations and forecast economic trends.

This study adopts an extension of the Jurado et al. (2015) procedure by combining financial uncertainty factors with their net spillover effects on GDP and inflation to construct an aggregate financial uncertainty index. The authors consider 13 monthly financial variables for Saudi Arabia from January 2010 to June 2021.

The empirical results show that the constructed financial uncertainty estimates are good leading indicators of economic activity. The robustness analysis suggests that the authors’ proposed financial uncertainty estimators outperform the alternative estimates used by other existing approaches to estimate the financial conditions index.

To the best of the authors’ knowledge, this is the first attempt at constructing a financial uncertainty index for Saudi Arabia. This study extends the empirical literature, from which the authors propose a novel conceptual framework for building a financial uncertainty index by combining the approach of Jurado et al. (2015) and the time-varying connectedness network approach proposed by Antonakakis et al. (2020)