17 research outputs found
The Effect of Corporate Governance on Firm Performance in Jordan
Due to widespread corporate scandals and failures around the world, there has been a renewed interest in the effect of corporate governance on firm performance. The majority of research concerning corporate governance and its effect on firm performance has been undertaken in developed countries and markets, particularly the UK and the US, but relatively little evidence is provided in the Middle East, specifically Jordan. This study investigates the effect of the corporate governance on firm performance of the Jordanian industrial and services companies during the period 2000 to 2010.
This study primarily employs the agency theory to investigate the relationship between corporate governance and firm performance. The agency theory is concerned with the agency problem between principals and agents (i.e. shareholders and managers, respectively), which undermines value maximization. It has been argued that the board
of directors, ownership concentration and managerial ownership are efficient corporate governance mechanisms to solve the agency problem between shareholders and management.
Multiple regression panel data analysis is the main tool of analysis in this study. The statistical method used to test this impact is Generalised Least Square (GLS) Random Effects
models. The study is based on the three sets of data: (1) a sample of 115 firms listed in the Amman Stock Exchange; (2) corporate governance data collected from Osiris database; and (3) data generated through the annual reports of the firms.
Empirical investigation reveals a mixed set of results. Our findings fail to reveal any significant impact for the board size on firm performance. However, CEO duality tends
to have a positive effect on the firm performance, which indicates that the Jordanian firms perform better if the chairman and the CEO roles are combined in a single
individual. It was also found that NEDs have a negative impact on firm performance, which is inconsistent with the monitoring hypothesis of agency theory, which holds that
the NEDs play an important role in the board as a source of experience, monitoring services, reputation and expert knowledge with the likelihood to improve firm performance. Furthermore, our findings report positive and negative impacts of managerial ownership and ownership concentration on firm performance (respectively).
Finally, our findings reveal a positive relationship between foreign ownership and firm performance
Numerical Simulation of One-Dimensional Shallow Water Equations
In this study, a relatively new semi-analytic technique, the reduced differential transform method is employed to obtain high accurate solutions of the famous coupled partial differential equations with physical interests namely the variable-depth shallow water equations with source term. The solutions are calculated in the form of a convergent power series with easily computable components. The Reduced differential transform method is easy to apply, reduces the size of computations, and produces an approximate solution without any discretization or perturbation. The results show the accuracy and efficiency of the reduced differential transform method in comparison to other existing methods
Hybrid feature selection method based on particle swarm optimization and adaptive local search method
Machine learning has been expansively examined with data classification as the most popularly researched subject. The accurateness of prediction is impacted by the data provided to the classification algorithm. Meanwhile, utilizing a large amount of data may incur costs especially in data collection and preprocessing. Studies on feature selection were mainly to establish techniques that can decrease the number of utilized features (attributes) in classification, also using data that generate accurate prediction is important. Hence, a particle swarm optimization (PSO) algorithm is suggested in the current article for selecting the ideal set of features. PSO algorithm showed to be superior in different domains in exploring the search space and local search algorithms are good in exploiting the search regions. Thus, we propose the hybridized PSO algorithm with an adaptive local search technique which works based on the current PSO search state and used for accepting the candidate solution. Having this combination balances the local intensification as well as the global diversification of the searching process. Hence, the suggested algorithm surpasses the original PSO algorithm and other comparable approaches, in terms of performance
Characterization and Construction of a Robust and Elastic Wall-Less Flow Phantom for High Pressure Flow Rate Using Doppler Ultrasound Applications
A Doppler ultrasound is a noninvasive test that can be used to estimate the blood flow through the vessels. Presently, few flow phantoms are being used to be qualified for long-term utilize and storage with high physiological flow rate Doppler ultrasound. The main drawback of the two hydrogel materials items (Konjac (K) and carrageenan (C) (KC)) that it is not fit for long-term storage and easy to deteriorate. Thus, this research study focuses on the characterization and construction of a robust and elastic wall-less flow phantom with suitable acoustical properties of TMM. The mechanisms for the fabrication of a wall-less flow phantom utilizing a physically strong material such as K, C, and gelatin (bovine skin)-based TMM were explained. In addition, the clinical ultrasound (Hitachi Avius (HI)) system was used as the main instrument for data acquisition. Vessel mimicking material (VMM) with dimensions of 15.0 mm depth equal to those of human common carotid arteries (CCA) were obtained with pulsatile flow. The acoustical properties (speed of sound and attenuation were 1533±2 m/s and 0.2 dB/cm. MHz, respectively) of a new TMM were agreed with the IEC 61685 standards. Furthermore, the velocity percentages error were decreased with increase in the Doppler angle (the lowest % error (3%) it was at 53◦). The gelatin from bovine skin was a proper material to be added to KC to enhance the strength of TMM during for long-term utilize and storage of high-flow of blood mimicking Fluid (BMF). This wall-less flow phantom will be a suitable instrument for examining in-vitro research studies
Evaluation of Gamma Radiation Properties of Four Types of Surgical Stainless Steel in the Energy Range of 17.50–25.29 keV
In this study, the gamma radiation properties of four types of surgical-grade stainless steel (304, 304L, 316 and 316L) were investigated. The effective atomic number Zeff, effective electron density Neff and half-value layer (HVL) of four types of surgical-grade stainless steel were determined via the mass attenuation coefficient (μ/ρ). The μ/ρ coefficients were determined experimentally using an X-ray fluorescence (XRF) technique and theoretically via the WinXCOM program. The Kα1 of XRF photons in the energy range between 17.50 and 25.29 keV was used from pure metal plates of molybdenum (Mo), palladium (Pd), silver (Ag) and tin (Sn). A comparison between the experimental and theoretical values of μ/ρ revealed that the experimental values were lower than the theoretical calculations. The relative differences between the theoretical and experimental values were found to decrease with increasing photon energy. The lowest percentage difference between the experimental and theoretical values of μ/ρ was between −6.17% and −9.76% and was obtained at a photon energy of 25.29 keV. Sample 316L showed the highest value of μ/ρ at the energies 21.20, 22.19 and 25.29 keV. In addition, the measured results of Zeff and Neff for all samples behaved similarly in the given energy range and were found to be in good agreement with the calculations. The equivalent atomic number (Zeff) of the investigated stainless-steel samples was calculated using the interpolation method to compare the samples at the same source energy. The 316L stainless steel had higher values of μ/ρ, Zeff and Zeq and lower values of HVL compared with the other samples. Therefore, it is concluded that the 316L sample is more effective in absorbing gamma radiation
Effect of the LEGe detector collimators on K-series peaks and Compton scattering in XRF analysis using gamma rays
The effect of a low-energy germanium detector collimator with different diameters on the measurement of the X-ray fluorescence of palladium (Pd) was studied experimentally. Changes in the Pd K-series and Compton scattering peaks were measured and analysed with and without a detector collimator, where for the former, collimators with different diameters were used. The signal-to-noise ratio increased when a shielding collimator was used with a narrow detector collimator. The Compton dispersion and fraction dead time were reduced considerably using a detector collimator by increasing the distance from the source to the detector, and the collimator length-to-diameter ratio. The full width at half maximum (FWHM) of the Pd Kα1 and Pd Kβ1 peaks decreased almost linearly with the collimator length-to-diameter ratio. The FWHM illustrated that the spectral resolution was improved when a collimator with a smaller diameter but unchanged length was used. The uncertainties at the Pd Kα1, Pd Kβ1, and Compton dispersion peaks were approximately correlated linearly with the collimator length-to-diameter ratio
Determination of the Attenuation Coefficients of Epoxy Resin with Carbopol Polymer as a Breast Phantom Material at Low Photon Energy Range
Six different composites of epoxy resin and Carbopol 974p polymer were prepared based on Carbopol 974p polymer concentrations of 0%, 5%, 10%, 15%, 20%, and 25%. The linear and mass attenuation coefficients, Half Value Layer (HVL), and mean free path (MFP) of these composites were determined using single-beam photon transmission in the energy range between 16.65 keV and 25.21 keV. This was carried out by determining the attenuation of ka1 X-ray fluorescent (XRF) photons from niobium, molybdenum, palladium, silver, and tin targets. The results were compared with theoretical values of three types of breast material (Breast 1, Breast 2, Breast 3) and Perspex, which was calculated using a XCOM computer program. The results show that there were no significant differences in the attenuation coefficient values after the consequent Carbopol additions. Moreover, it was found that the mass attenuation coefficients of all tested composites were close to those of Perspex and the values for Breast 3. The HVL and MFP results showed that the E25 sample is closer to the results of the Perspex material with differences of (0.53–1.15%) and (0.51–1.20%), respectively. In addition, the densities of the fabricated samples were in the range of 1.102–1.170 g/cm3, which is in the range of human breast density. A computed tomography (CT) scanner was used to investigate the CT number values for the fabricated samples. The CT numbers of all samples were in the range of human breast tissue (24.53–40.28 HU). Based on these findings, the fabricated epoxy–Carbopol polymer is a good candidate for use as a breast phantom material
Cross-Sectional Relationship Between Beta and Realized Returns in Emerging Markets
Abstract
This paper examines the conditional risk-return relationship caused by the impact of using realized returns as a proxy for expected returns, which requires a separation of negative and positive market premiums. Following the methodology of Pettengill et al. (1995), we test the cross sectional relationship between beta and realized returns on the Amman Stock Exchange (ASE) for ten beta sorted portfolio over the period of January 1993 to December 2016. The empirical results suggest that the traditional two-pass approach produces an insignificant relationship between beta and realized returns in most of the sample period. However, when adjusting for negative market premiums, the results show a significant and consistent relationship for all the testing periods and samples. However, a guaranteed reward for holding extra risk occurred only in the period 2001 –2008, which suggests an assurance of positive risk-return tradeoff during bull markets.
JEL Classifications: G11, G12, G15, C21
Asset Pricing, Emerging Markets, Conditional Relationship, Beta, Market Premiu
Contribution of financial market development in competitiveness growth
The study aims at re-examining the relationship between financial market development and economic development in the context of competitiveness of developed and higher income countries. Methodology/approach: The study employs generalized least square (GLS) regression model to analyze the panel data of 21 higher income countries over the period (2009-2017). Further, the study checked the robustness of the results by introduces a lagged dependent variable in the regression models by employing the generalized methods of moments (GMM) for Dynamic Panel analysis. Findings: Results reveal that four independent variables: Financial market development (FMDG), trade openness (OPNG), Labor market efficiency (LMEG), and Technological readiness (TRG), were positive and significant, which indicates the existence of relationship from those variables to competitiveness in the context of growth. while one of the independent variables is Market size (MSG) was positive but insignificant. Moreover, the results from the GMM estimator remain robust in terms of directions and significance levels and confirm the robustness of the findings. Originality: This paper represents a significant contribution especially for the higher income countries that can help them in designing the policies and strategies in order to improve their performance and competitiveness by financial market development besides other competitiveness sources
Evaluating the Effects of Metallic Waste on the Structural and Gamma-Ray Shielding Properties of Epoxy Composites
The objective of the research is to develop novel materials that are both inexpensive and have a low density, while also being able to endure the transportation of γ-photons with low-to-medium energy levels. The outcome consisted of four epoxy resins that were strengthened with different quantities of heavy metallic waste. The density of the formed composites improved from 1.134 ± 0.022 g/cm3 to 1.560 ± 0.0312 g/cm3 when the waste content was raised from 0 to 40 weight percent. The theoretical investigation was determined using Monte Carlo (MCNP) simulation software, and the results of linear attenuation coefficient were justified experimentally in a low and medium energy range of 15–662 keV. The mass attenuation coefficient results in a low gamma energy range (15–122 keV) varied in between 3.175 and 0.159 cm2/g (for E-MW0 composite) and in between 8.212 and 0.164 cm2/g (for E-MW40 composite). The decrease in mass attenuation coefficient was detected in a medium gamma photon energy range (122–662 keV) with 0.123–0.082 cm2/g (for E-MW0 composite) and 0.121–0.080 cm2/g (for E-MW40 composite). The density of the enhanced composites influenced these parameters. As the metallic waste composition increased, the fabricated composites’ half-value thickness decreased. At 15 keV, the half-value thickness decreased from 0.19 to 0.05 cm. At 59 keV, it fell from 2.70 to 1.41 cm. At 122 keV, it fell from 3.90 to 2.72 cm. At 662 keV, it fell from 7.45 to 5.56 cm. This decrease occurred as the heavy metal waste concentration increased from 0 to 40 wt.%. The study indicates that as metallic waste concentrations rise, there is a rise in the effective atomic number and a decline in the buildup factors