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Trade Liberalization with BRICS: A CGE Model of Egypt
Get PDFThis paper presents an ex-ante impact assessment of a hypothetical FTA between Egypt and the BRICS from an Egyptian economy-wide and sectorial perspectives, with a granular look into manufacturing. The chosen methodology is a static SAM-based Computable General Equilibrium model calibrated to Egypt’s 2018-2019 Social Accounting Matrix (SAM). With respect to existing literature, the paper uniquely stands in considering an Egypt-BRICS FTA with a granular assessment of manufacturing subsectors and in running a simulation of Egypt’s trade liberalization with the wider BRICS alliance, including the accession of Saudi Arabia, UAE, Ethiopia, and Iran, which joined the bloc along with Egypt in January 2024. Beside the wider BRICS simulation, the model is used to run a simulation with core BRICS members. Magnified upon considering the wider bloc, results predict an increase in real consumption across all household income quantiles with the poor generally reaping more of the welfare gains, defined as the increase in household real consumption. Real GDP expands while inflation is imported on the back of local currency depreciation, implying a positive exchange rate pass-through. On a sectorial level, sectors reliant on local intermediate inputs suffer as they don’t benefit from decreased import prices while still facing foreign competition. On the other hand, sectors with initially competitive export prices thrive on the back of a cheaper local currency
Mechanical and Electromagnetic Properties of Incorporating Graphene Oxide in Cementitious Mixtures
Get PDFThis multidisciplinary study aimed at investigating the impact of incorporating graphene oxide (GO) on the mechanical properties and electromagnetic (EM) shielding effectiveness of cementitious mixtures, as well as critically examining the mechanism with which GO affects their microstructure properties. Analysis of the literature review showed that there are discrepancies in reporting the impact of GO on the mortar mix. Consequently, this study focuses on exploring the cause for such discrepancies and identifies three main factors which are thoroughly investigated. The factors were the different sonication energies applied to the GO (Shear Mixing, 1.5 kJ/ml, 3 kJ/ml and 6 kJ/ml), the dosage of the GO incorporated in the mix (0.05%, 0.1%, 0.2%, 0.4%) as a percentage of the binder content, and the different mixing techniques (dry mixing and wet mixing) of incorporating GO in the mortar mix. Detailed analysis was conducted using Scanning Electron Microscopy (SEM), Zeta Potential, Zeta Size, Energy Dispersive X-Ray (EDX) Spectroscopy, X-Ray Diffraction Analysis (XRD), Ultraviolet-Visible (UV-vis) spectroscopy, Fourier Transform Infrared (FTIR) Spectroscopy, Surface Analysis and Porosity. These tests have all been carried out to visualize and prove the impact that these three main factors could induce to the mix. Adopting a wet mixing technique using a sonication energy of 3 kJ/ml with GO content of 0.05% of the binder content induced the optimum positive impact on the different properties tested. The compressive strength and flexural strength increased by 32% and 20.7% respectively compared to the control mix after 28 days using 0.05% GO. The results of the microstructure tests conducted (SEM, XRD, FTIR, Surface Analysis and Porosity) proved that the addition of the GO induced chemical changes/reinforcement to the cement mortar mix affecting its hydration which in turn increased its strength. Furthermore, relatively little work targeted the effect of incorporating graphene in cement mortar for shielding EM waves at low frequencies despite its promising properties. This is why this study explored the advantages of using GO in shielding EM waves at low frequencies. The frequency of interest was 2.4 GHz since Wi-Fi operates at this frequency. A comparison between the electromagnetic shielding effectiveness gains due to incorporating different dosages of GO (0.05%, 0.1%, 0.2%, 0.4%) as a percentage of the binder content used in the mortar mix have been carried out . Limited increase in EM shielding effectiveness has been identified for the 0.05% GO of only 8% (in terms of dB) relative to the control mix after 28 days. Accordingly, additional conductive material, the Iron Filling (IF), has been introduced in order to attain sufficient EM interference attenuation results, while protecting the environment. In this regard, Response Surface Methodology (RSM) using the software Design Expert v.13 was used to identify, visualize, and predict the impact of introducing three independent factors (GO, Iron Filling (IF), Silica Fume (SF)) on the compressive strength of the cement mortar mix as well as its corresponding EM shielding effectiveness. Five levels of percentage of GO (0%, 0.025%, 0.05%, 0.075% and 0.1%) of the binder content, 3 levels of percentage of IF (0%, 25%, and 50%) of the aggregate content and 3 levels of SF (0%, 5% and 10%) of the binder content were incorporated inside the software. Twenty different mix designs were produced and analyzed. The model results confirmed that increasing the GO up to 0.05% yielded the highest compressive strength results, however, additional dosage of GO had a negative impact on the compressive strength. In addition, replacing 50% of the aggregate content by IF increased the electromagnetic shielding effectiveness by 104% (in terms of dB) relative to the control mix. On the other hand, when 10% of the SF is used of the binder content, while the percentage of IF is 0% of the aggregate content and GO 0% of the binder content, the EM shielding effectiveness decreased by 7.8% (in terms of dB), however, the EM shielding effectiveness increased by 12% (in terms of dB) when the IF content became 50%, and the GO 0.1% due to incorporating 10% SF. According to the developed RSM model, the resulting cement mortar composite of 12.5 mm thickness with the highest EM shielding effectiveness provided electromagnetic attenuation up to around 11 decibels (dB) for 2 GHz frequency, and around 8 dB for 2.4 GHz frequency for the mix containing 50% Iron filling and 0.1% GO of the binder content which is deemed sufficient for the purpose of protecting structures from EM wave interference. Moreover, two empirical equations were developed from the RSM model and validated successfully for calculating the compressive strength and EM shielding effectiveness. Finally, the viability of incorporating GO in the cement mortar mix in terms of availability, transportation, and workmanship has been discussed. A cost comparison between using the proposed mortar composite section and the conventional alternative of covering the perimeter with steel sheets was presented and the results showed that it is currently practical, cost effective and environmentally friendly to shield incident EM waves using GO and iron filling. Ultimately, this study is a step on the way for researchers interested in exploring the benefits of incorporating GO to enhance the mechanical properties as well as the EM shielding effectiveness of cementitious mixtures
Fiscal Administration Versus Fiscal Policy: An Investigation into the Determinants of the Real Tax Revenues from Consumption Tax in Egypt
Get PDFThis thesis highlights the importance of fiscal administration relative to fiscal policies. It presents a broad view of the developments in both fields and tests their effects on real revenues from consumption tax in Egypt from fiscal year 2002 till 2023. It initially explains the proxies used for fiscal administration: the size of the tax base and the collection lag. The major fiscal policy change in Egypt was shifting from sales tax to Value-Added Tax (VAT) during fiscal year 2016/17. The effects of fiscal administration and fiscal policy on real tax revenues will be assessed using the Autoregressive Distributed Lag (ARDL) model for 22 years
Effects of Moringa oleifera aqueous extract on the growth performance, blood characteristics, and histological features of gills and livers in Nile tilapia
No full textA 3D Imaging-based Critique of Wire Arc Additive Manufacturing (WAAM) Simulations
Get PDFResidual stresses play a critical role in the mechanical behavior and structural integrity of engineered components. Understanding and quantifying these stresses are essential for ensuring the reliable performance and durability of materials and structures. Traditionally destructive methods are used that involve sample sectioning and material removal. However, non-destructive methods have gained popularity due to their advantages in preserving the specimen\u27s integrity for further testing and material waste reduction. Among these techniques, Digital Image Correlation (DIC) stands out as a powerful non-contact and full-field measurement approach. DIC captures displacements and strain distributions by analyzing the deformation of speckle patterns on the sample surface. It enables the extraction of residual stresses without damaging the specimen. Despite its advantages, current DIC methods primarily focus on 2D images, limiting the ability to capture the full strain field in complex 3D geometries. In this study, a novel in-situ and non-destructive methodology for measurements of residual stresses in Wire Arc Additive Manufacturing (WAAM) components using three-dimensional imaging is proposed. The methodology involves utilizing non-rigid registration to map the 3D scanned mesh of the deformed component onto a CAD template representing the undeformed component. By aligning the two surfaces, the residual strains that arise during the additive manufacturing process are captured. The measured residual stresses were compared to the results of WAAM simulation and benchmarked against process characteristics. The results demonstrated a remarkable agreement between the measured displacements and the simulations, confirming the robustness and accuracy of the proposed technique. Additionally, the measured residual stresses were shown to be significantly lower than its FE simulation counterpart. This was attributed to the fact that the depositions were separated from the substrate and thus exist in an unclamped state, which is expected to have lower stress values. Finally, the procedure was repeated for a deposition with higher heat input which yielded larger residual stresses. This showed the potential of the proposed methodology for providing an in-situ and quick feedback optimization of WAAM process parameters
Exploration of sustainable attitudes and behaviors and the role of planned behavior amongst the AUC Community
Get PDFThis thesis explores the use of a new Framework that was developed by combining both the Theory of Planned Behavior (TPB) and Knowledge, Attitudes, and Practices (KAP) theory to study the sustainability behaviors of students, faculty, and staff at the American University in Cairo (AUC). The research aims to provide insights into the factors influencing sustainable behaviors and how these factors differ across the three groups. The study used a combination of questions from the sustainability awareness questionnaire (SAQ) and Sulitest that was customized to the cultural context of the target group. The survey was administered to a sample of students, faculty, and staff at the AUC. The data collected was analyzed using SPSS to create both linear and multiple regression models to understand the impact of the independent variables on the dependent variables. The results of the study indicated that both extended TPB and the new framework were useful in understanding sustainable behaviors but that they provide different insights. The results also suggest that the factors that influence sustainable behaviors are complex, and that they vary across different groups. While perceived behavioral control and attitudes were found to be important factors for all groups, knowledge and awareness were more important for staff than for students or faculty. The study has several implications for sustainable behavior interventions; it suggests that using the newly proposed conceptual framework helped in better understanding the factors impacting behavior. Furthermore, it highlights the importance of addressing knowledge and awareness gaps, particularly for staff. Overall, it highlights the need to address the broader social and cultural context in which sustainable behaviors occur, and it contributes to the overall understanding of researchers of sustainable behaviors for designing effective interventions to promote sustainability in higher educational institutes
The Effect of Mechanical Strain On the Electronic Conductivity of Α- Fe2O3: A Density Functional Theory Study
Get PDFHydrogen has emerged as a promising future energy carrier due to its ability to produce zero carbon dioxide (CO2) emissions when burned. However, the limited natural abundance of hydrogen necessitates the development of cost-effective and environmentally friendly methods for large-scale hydrogen production. Among the different hydrogen production approaches, photoelectrochemical water splitting, which employs a photoanode material in a cell using solar energy to split water into hydrogen and oxygen, is the focus of this work. α-Fe2O3 (hematite) is a photoanode material that shows a promising future for hydrogen generation in a photoelectrochemical cells due to its cheapness, availability, and its capacity to absorb light within the range of visible spectrum. Nevertheless, when compared to other photoanode its main drawback is its overall low electronic conductivity, adversely affecting its activity as a photoanode material. Meanwhile, mechanical strain is known to modulate transport processes in materials including electronic conductivity. Herein, we aim to understand the effect of biaxial strain both compressive and tensile on changing the electronic conductivity of hematite. Prior work showed that in strain-free hematite slow small polarons predominates over fast large polarons (or free carriers) but they both co-exist. We explore the effect of biaxial mechanical strain on the electronic conductivity of hematite using density functional theory calculations with on-site Hubbard U terms on oxygen p-states and iron d-states. We apply biaxial strain in increments of 0.5% from −5% to +5% and find that the bandgap reduction occurs under both tensile and compressive strain, with a more significant reduction observed in the compressive strain state. We also observe an increase in free electron effective mass and a decrease in free hole effective mass as we move from the tensile to the compressive strain state. Moreover, we investigate the effect of mechanical strain on polarons of hematite and find out that it cannot change the energy landscape in favor of large polaron electrons (or free electrons). However, mechanical strain can alter the energy landscape in favor of large polaron holes (or free holes). This implies that applying slight compressive strain can enhance the overall electronic conductivity in hematite via reducing the band gap, increasing the concentration and the mobility of holes especially via large hole polarons while not significantly affecting the mobility of electrons. These findings provide insights into modulating the electronic conductivity of hematite, which can promote its use as a photocatalyst for hydrogen production, addressing the increasing energy demand and mitigating the impact of climate change
Blooming through the Cracks: The Case of Syrian Women in Egypt After 2011
Get PDFThis study was conducted in 2023 and aims to understand the impact of displacement on Syrian women’s involvement in the public sphere in Egypt. After the transition of the Syrian revolution into an armed conflict, Syrians witnessed a large wave of displacement, looking for safety away from their homeland. The research defines displacement as the movement of people who are forced to leave their place of residence. The focus is directed on the situation of Syrian women who were displaced to Egypt after 2011, and it proves the claims that there is an increase in women’s engagement in the public sphere because of displacement. Moreover, this thesis aims to compare the level of civic engagement upon displacement to that happening prior to displacement. The fieldwork has been done with Syrian women and men in different locations in Cairo and Giza. It integrates their perceptions of women’s role in the community during displacement within the research findings. This study was encouraged by the lack of studies highlighting women’s and men’s perceptions regarding women’s experience in the public sphere in Egypt, especially after their displacement reached its twelfth year
Automated Management of Time Extension Claims in Construction Projects
Get PDFDisputes within the construction industry have caused parties to incur additional costs not accounted for. In fact, one of the notorious reasons for disputes can be attributed to Extension of Time (EOT) claim submissions. Such is due to its susceptibility to the human factor. Accordingly, there is a need to diminish reliance on the human factor in the EOT process and to bolster it with commodities of the industrial revolution 4.0. While research efforts have endeavored in tackling the drawbacks of the EOT claim process individually, no superior solution is provided to overcome all drawbacks at once. Initially, the literature was analyzed by utilizing a citation-based mapping tool to pinpoint the prominent features affecting the success of the EOT claim process. Then, disadvantages of the features were analyzed within the literature as follows: poor record keeping, delayed event notification, an arduous process of EOT-related clauses within contracts, the lack of a superior delay analysis technique (DAT), no automation of a DAT, lack of standardized EOT submission reports, and finally mistrust/security issues between parties This research strives to overcome the disadvantages present within the EOT submission process caused by the human factor by creating a web-based EOT management system model utilizing a distributed platform shared between all parties to decentralize and proactively deal with EOT claim management. The model, Automated Management of Time Extension Claims (AMTEC), was created using ASP.NET: a cross-platform for web development powered by Microsoft. The language used to develop AMTEC is C# (C-Sharp). Features of AMTEC are tailored to overcome the EOT seven drawbacks through: live delay information updates and approvals inclusive of relevant documentation; natural language programming to extract EOT-related clauses; a superior DAT that was created to overcome existing DATs drawbacks’; the automation of the DAT through the model that not only obliterates the manual aspect but also the need to deal with a complicated project management software; and finally a standardized reporting system that generates a claim tailored to the needs of the engineer for the ease of the claim review process. This research also explores a framework for future implementation of the model through blockchain technology to facilitate interactions between parties within the delay analysis implementation process and create a secure, auditable network to increase the level of trust between the parties. AMTEC was then applied to a case study involving an EOT claim submission; it was initially applied manually and then using AMTEC. The level of effort, duration, and disputes within the entire process were compared in both scenarios. Results show that the duration for the processes decreased by 79% and the level of effort was decreased by 52%. Disputes within both scenarios were further analyzed and it was established that AMTEC was capable of overcoming the disputes faced within the manual process between parties. Thus, creating the foremost application of a claim management system, involving all parties, that is carefully designed to allow an efficient and less disputed EOT submission