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Determining The Limitations Of Class F Fly Ash Compared To Class G Cement In Hydrocarbon Wells Application, Youssef Helmy Feb 2025

Determining The Limitations Of Class F Fly Ash Compared To Class G Cement In Hydrocarbon Wells Application, Youssef Helmy

Theses and Dissertations

Cement is a material commonly used in multiple applications in different industries. Among the industries that uses cement is the oil and gas industry. API (American Petroleum Institute) Class G cement that is the most incorporated form of cement used in the cementation of oil and gas wells to provide several forms of protection and stabilization for the casings. However, Class G cement is contested in terms of efficiency, costs, and environmental awareness against Class F fly ash geopolymers by researchers. This research aims to explore the potential limitations that fly ash geopolymer might have for its use in the …


Predicting The Indirect Cost Of Construction Projects In Egypt: An Artificial Neural Network Approach, Aya Effat Feb 2025

Predicting The Indirect Cost Of Construction Projects In Egypt: An Artificial Neural Network Approach, Aya Effat

Theses and Dissertations

Cost estimation is one of the vital processes in construction management that needs to be done early in any project in order to determine the project's budget. The accuracy of the cost estimate is a key factor in the success of construction projects since it enables project managers to successfully control the project’s expenses. Construction costs mainly consist of direct cost and indirect cost. Generally, indirect costs can be categorized into two types: site overheads and general overheads. In a construction project, overheads, particularly site overhead costs, make up a considerable portion of a contractor's budget. Accordingly, accurately estimating the …


Design And Implementation Of Uvm-Based Verification Framework For Deep Learning Accelerators, Randa Ahmed Hussein Aboudeif Jan 2025

Design And Implementation Of Uvm-Based Verification Framework For Deep Learning Accelerators, Randa Ahmed Hussein Aboudeif

Theses and Dissertations

Recent advancements in deep learning (DL) have made hardware accelerators, known as deep learning accelerators (DLAs), a preferred solution for numerous high-performance computing (HPC) applications, including speech recognition, computer vision, and image classification. DLAs are composed of hundreds of parallel processing engines to speed up computations and can gain access to pre-trained networks from the cloud or through on-chip memory to implement the DNN inference process. DLA verification is becoming an important and challenging phase. The verification process is required to handle the complex DLA design. Moreover, the reliability of DLAs is critical for assessment as they are involved in …


Organizational Change Management In Egypt; Contractors’ Perspective, Karim Ayoub Jan 2025

Organizational Change Management In Egypt; Contractors’ Perspective, Karim Ayoub

Theses and Dissertations

Organizational change management in the construction industry is a vital process for companies to consider in their operations. Successful implementation of the process allows the companies to go a step further in the market due to their competitiveness derived from better performance and efficiency. However, applying change to the organization and introducing new structure is a challenge for any company seeking better performance, but worth it if it is implemented properly. In general, this research sheds light on the organizational change management implementation in construction contractors in Egypt. Where, this study aims to demonstrate the organizational change management initiatives and …


Operation And Maintenance Costs In Reverse Osmosis Desalination Projects Adopting Public-Private Partnerships: A Comprehensive Investigation And Analysis, Mayar Mohamed Khairy Jan 2025

Operation And Maintenance Costs In Reverse Osmosis Desalination Projects Adopting Public-Private Partnerships: A Comprehensive Investigation And Analysis, Mayar Mohamed Khairy

Theses and Dissertations

Water Desalination projects, specifically ones adopting reverse osmosis (RO) technology, play a pivotal role in addressing the scarcity of water globally. Since these projects require huge investments, there is an imperative need to focus on the role of public-private partnerships (PPPs) in their developments. This research tries to provide a comprehensive investigation into the factors affecting O&M costs in PPP desalination projects due to their importance.

A comprehensive research approach, including a literature review, expert interviews, survey analysis, and statistical tools, is adopted in this research aiming to identify key factors and recommendations based on best practices in O&M costs …


Advanced Construction Scheduling: Capturing Conditional And Stochastic Relationships, Amr Elsabagh Jan 2025

Advanced Construction Scheduling: Capturing Conditional And Stochastic Relationships, Amr Elsabagh

Theses and Dissertations

Proper planning is a key factor in all business endeavors. This is especially important in the construction industry as a project is sensitive to countless factors that affect the project's time and cost. This created the need for agile and flexible schedules for close monitoring and dynamic planning for construction projects. The currently prevailing scheduling techniques are CPM and PERT, which professionals in the field widely use. These methods create static schedules that are vulnerable to any changes in the schedule logic, which often happens during construction projects. In addition, these Scheduling techniques do not capture the uncertainties and complex …


Metakaolin-Based Geopolymer Concrete; Synthesis, Development And Characterization, Heba Fouad Dec 2024

Metakaolin-Based Geopolymer Concrete; Synthesis, Development And Characterization, Heba Fouad

Theses and Dissertations

Geopolymers are rendered as an essential sustainable replacement to the widely used Ordinary Portland Cement (OPC) which causes immense carbon dioxide emissions, hence a detrimental impact on society’s health and the environment. Geopolymers are three-dimensional networks of polymerized tetrahedral silicate and aluminate in the form of Q4(4Al), Q4(3Al) and Q4(2Al) which act as the principal binding phase in concrete. Past research has reported the synthesis of geopolymers from different aluminosilicates precursors, their characterization, and their wide range properties. However, previous studies still have not properly investigated effective range of synthesis ratios for a particular source material, optimum curing regimes, short- …


Enhancing Concrete Sustainability With Self-Healing Technologies, Al Shimaa Abdullatif Dec 2024

Enhancing Concrete Sustainability With Self-Healing Technologies, Al Shimaa Abdullatif

Theses and Dissertations

Thanks to its strength, durability and affordability, Portland cement concrete is the most commonly used building material worldwide. However, concrete cracking is inevitable due to numerous factors including shrinkage, exposure to external chemicals, internals reactions, excessive loads, to name but a few. Self-healing is a promising technique that can enable concrete to autogenously heal cracks and alleviate much of the damage. Such healing can without a doubt extend the service life with less need for external repair works therefore it contributes to sustainability. Over the years, several means of self-healing agents have been explored including bio-based procedures and the incorporation …


Identifying Challenges Faced By Small And Medium Enterprises (Smes) In The Middle East And North Africa (Mena) Region Through Total Quality Management, Mohamad Atef Dec 2024

Identifying Challenges Faced By Small And Medium Enterprises (Smes) In The Middle East And North Africa (Mena) Region Through Total Quality Management, Mohamad Atef

Theses and Dissertations

Recently, Small and Medium Enterprises (SMEs) have become recognized as an important driver of global economic growth and innovation. This phenomenon is particularly evident in the MENA region, where small and medium-sized enterprises (SMEs) make a significant contribution to the businesses. SMEs offer significant benefits in terms of job creation, revenue generation, and fostering economic diversity. Although SMEs have a vital contribution in the economy of the MENA region, SMEs face many challenges that hinder their development and long-term viability. Focusing on these challenges is very important for fostering a vibrant and resilient economic environment. The objective of this thesis …


Shape Memory Alloy Capsule Micropump For Drug Delivery Applications, Youssef Mohamed Kotb Jun 2024

Shape Memory Alloy Capsule Micropump For Drug Delivery Applications, Youssef Mohamed Kotb

Theses and Dissertations

Implantable drug delivery devices have many benefits over traditional drug administration techniques and have attracted a lot of attention in recent years. By delivering the medication directly to the tissue, they enable the use of larger localized concentrations, enhancing the efficacy of the treatment. Passive-release drug delivery systems, one of the various ways to provide medication, are great inventions. However, they cannot dispense the medication on demand since they are nonprogrammable. Therefore, active actuators are more advantageous in delivery applications. Smart material actuators, however, have greatly increased in popularity for manufacturing wearable and implantable micropumps due to their high energy …


Navigating The Rules: Integrating Td3 And Sensor Fusion For Traffic-Aware Autonomous Vehicle Path Planning, Mahmoud Ayman Mohamed Elsayed Jun 2024

Navigating The Rules: Integrating Td3 And Sensor Fusion For Traffic-Aware Autonomous Vehicle Path Planning, Mahmoud Ayman Mohamed Elsayed

Theses and Dissertations

This work presents a novel algorithm for local path planning for autonomous vehicles (AVs) which prioritizes both safety and adherence to traffic regulations, addressing critical functions for AV navigation, such as navigating complex environments, avoiding obstacles, and ensuring passenger and road users safety. The algorithm integrates the Twin Delayed Deep Deterministic Policy Gradient (TD3) with sensor fusion based on Nvidia Convolutional Neural Network (NCNN). The study utilizes the CARLA simulator, and real-world datasets, including KITTI and WAYMO, to train and evaluate the proposed algorithm. The proposed algorithm leverages the complementary strengths of Imitation Learning (IL) and Deep Reinforcement Learning (DRL) …


Physical Effects On The Worst-Case Delay Analysis And Signal Integrity Of Buses And Spirals, Mahmoud Mahany Jun 2024

Physical Effects On The Worst-Case Delay Analysis And Signal Integrity Of Buses And Spirals, Mahmoud Mahany

Theses and Dissertations

Physical effects have a significant impact on the IC design which will be investigated in this thesis. Moving toward advanced technology nodes, magnetic effects become more dominant than capacitive effects. As the dimensions of the devices go down and the interconnect manipulates the circuit behavior more and more. Cross talking and voltage drops are affecting the design heavily, however - going to the full electromagnetic point of view - current return path (CRP) adds significant parasitics to the performance of the chip. Neglecting the CRP gives wrong intuition and simulation of the designs, especially that the environment and surroundings can …


Prediction Of Distresses In Pavement Networks: A Machine Learning Approach, Mahmoud Kotb Feb 2024

Prediction Of Distresses In Pavement Networks: A Machine Learning Approach, Mahmoud Kotb

Theses and Dissertations

The quality of pavement networks is greatly affected by different distresses. These distresses appear in many forms, such as cracking, potholes, rutting and different types of deformation. As a result, to ensure effective pavement management, accurate modeling of these different distresses has become essential. Moreover, machine learning models have shown great potential in modeling pavement performance in recent years. The objective of this research is to develop machine learning models for modeling key parameters of pavement distress, specifically the International Roughness Index (IRI), fatigue and longitudinal cracking. Data for this investigation were extracted from the Long-Term Pavement Performance (LTPP) database, …


Assessing Adoption Barriers Of Sustainable Packaging In Egypt, Carol Ramses Morgan Feb 2024

Assessing Adoption Barriers Of Sustainable Packaging In Egypt, Carol Ramses Morgan

Theses and Dissertations

Sustainable packaging has become an essential part of business decisions and corporate directions. With the rise of environmental damages due to improper waste management and unsustainable practices, businesses have a major responsibility to analyze their products’ life cycles and redesign them with sustainability in mind. Applying sustainable packaging could save companies large amounts of resources, therefore cutting costs, while also achieving the legal and social duty as a corporation towards society and the environment. Many developing countries, with specific focus on Egypt, have recently focused on legislative and corporate decisions in order to encourage more sustainable practices. Egypt’s new Waste …


Applicability Of Using Bio-Receptive Concrete For Building Facades In Egypt, Gina Roupheil Feb 2024

Applicability Of Using Bio-Receptive Concrete For Building Facades In Egypt, Gina Roupheil

Theses and Dissertations

The significant increase in carbon dioxide emissions caused by the construction industry is detrimental to our planet. This is rapidly increasing with the urbanization of cities that is gradually taking its toll on the available green spaces, which help in balancing such emissions. Recently, researchers have been trying to make use of bio-receptivity to create biomaterial systems that could be spread on building envelopes and support the growth of small plant species and microorganisms to establish on. Out of those materials, comes the concrete as a promising material for bio-colonization.

Within this context, this study aims at investigating the applicability …


Consumers' Acceptance To Buy And Dispose Of Recycling Textile Products, Roa Alsayed Feb 2024

Consumers' Acceptance To Buy And Dispose Of Recycling Textile Products, Roa Alsayed

Theses and Dissertations

The textile industry is the second most polluting worldwide, following food manufacturing. It is one of the industries that is rarely scrutinized in the Middle East and North Africa (MENA) region. This work analyzes the fashion industry from the perspective of consumer attitudes towards the purchase and disposal of clothing, and their behavior with regards to old garments. The study was conducted in Saudi Arabia and Egypt, two countries that achieved similar results in the fashion industry. The methodology is divided into three phases. First, the manuscript begins with a review of topics such as sustainability, consumer behavior in the …


Properties Of Portland Cement Concrete Incorporating Basalt-Based Pozzolanic Cement, Rana Khalil Feb 2024

Properties Of Portland Cement Concrete Incorporating Basalt-Based Pozzolanic Cement, Rana Khalil

Theses and Dissertations

Over the last decade, the world's population has increased dramatically. Due to this growth, the demand for concrete and Portland cement, in return, have increased. Manufacturing of Portland cement is an energy-intensive process that, alone, contributes to about 8% of global CO2. For decades, efforts have been exerted to reduce the harmful environmental impacts of Portland cement by reducing its use in concrete as well as considering alternate binders that may fully or partially replace it. This study aims to assess the properties of concrete incorporating a novel basalt-based pozzolanic cement. To meet this objective, four sets of concrete mixtures …


Developing And Forecasting The Egyptian Construction Cost Index, Mayada Elsaied Feb 2024

Developing And Forecasting The Egyptian Construction Cost Index, Mayada Elsaied

Theses and Dissertations

Accurate cost estimation is pivotal for the success of construction projects, yet the industry grapples with challenges related to cost overruns. Uncertainties and unforeseen variables often introduce discrepancies, particularly during the planning phase. Economic changes, considered uncontrollable risks, significantly influence these fluctuations. Various research endeavors have quantified the impact of economic conditions on construction costs, emphasizing the correlation between economic indicators and project expenses. Addressing these challenges, the Construction Cost Index (CCI), a tool introduced by Engineering News Record (ENR), accurately delineates the correlation between economic changes and construction costs. Despite its global efficacy, an Egyptian Construction Cost Index is …


Customer Churn Prediction Based On Sentiment Score, Shadha Al-Safi Feb 2024

Customer Churn Prediction Based On Sentiment Score, Shadha Al-Safi

Theses and Dissertations

In recent years, the telecommunications industry has witnessed intensified competition, wherein the expense associated with acquiring new consumers exceeds that of sustaining existing ones. Consequently, predicting customer churn prior to its occurrence has become essential. This study proposes a sentiment-based customer churn prediction model in which the sentiment of customers is predicted using Random Forest. Subsequently, the derived sentiment predictions are combined with additional features to predict customer churn. The ensemble technique is applied to predict churn, consisting of K-nearest neighbors, Support Vector Machines, Random Forest as base learners, and Multiple Layer Perceptron as a meta learner. Moreover, mutual information …


Fair Fault-Tolerant Approach For Access Point Failures In Networked Control System Greenhouses, Mohammed Ali Yaslam Ba Humaish Feb 2024

Fair Fault-Tolerant Approach For Access Point Failures In Networked Control System Greenhouses, Mohammed Ali Yaslam Ba Humaish

Theses and Dissertations

Greenhouse Networked Control Systems (NCS) are popular applications in modern agriculture due to their ability to monitor and control various environmental factors that can affect crop growth and quality. However, designing and operating a greenhouse in the context of NCS could be challenging due to the need for highly available and cost-efficient systems. This thesis presents a design methodology for greenhouse NCS that addresses these challenges, offering a framework to optimize crop productivity, minimize costs, and improve system availability and reliability. It contributes several innovations to the field of greenhouse NCS design. For example, it recommends using the 2.4GHz frequency …


Cardiac Active Tension Modeling Via Genetic Algorithm-Optimized Fractional Order Systems, Afnan Khaled Elhamshari Jan 2024

Cardiac Active Tension Modeling Via Genetic Algorithm-Optimized Fractional Order Systems, Afnan Khaled Elhamshari

Theses and Dissertations

Developing a computational model to model cardiac activity has been increasingly important in recent decades. Accurate cell-level active tension modeling for cardiomyocytes is critical to understanding cardiac functionality on a patient-specific basis and developing an effective in-silico cardiac model. However, cell-level models in the literature fail to account for viscoelasticity and inter-patient variations in active tension. This research proposes a genetic algorithm-optimized, fractional order system to model cell-level active tension by extending Land’s state-of-the-art model of cardiac contraction. The model features the (left) Caputo derivative of six state variables that identify the mechanistic origins of viscoelasticity in a myocardial cell …


Study Of Vortices Formation In Lateral Intakes Of Pumping Stations, Muhammad Elgindi Jan 2024

Study Of Vortices Formation In Lateral Intakes Of Pumping Stations, Muhammad Elgindi

Theses and Dissertations

The inefficient design of pumping stations leads to undesirable flow characteristics and the formation of vortices in the sump. These undesirable flow features adversely affect the pumping unit performance and increase the operation and maintenance cost. The aim of this thesis is to assess the ability of the Realizable turbulence model to predict the formation of free-surface and submerged vortices within lateral pumping stations’ intakes. Additionally, the study aims to investigate the effect of the flow ratio and bottom clearance on the flow characteristics and the vortices formation in the sump. Finally, the study introduces an assessment of curtain walls …


Optimization Of Vibro-Seismic Parameters For Enhanced Oil Recovery Application, Tarek Abdel Aal Jan 2024

Optimization Of Vibro-Seismic Parameters For Enhanced Oil Recovery Application, Tarek Abdel Aal

Theses and Dissertations

This thesis was conducted in the American University in Cairo by Tarek Ahmed Abdel Fattah Abdel Aal. The thesis is titled ‘Optimization of Vibroseismic Parameters for Enhanced Oil Recovery Application.’ The thesis discusses whether or not the combination of optimized physical vibration parameters with waterflooding would improve porosity, absolute permeability, relative permeability, and recovery when compared with just classical waterflooding. The optimized physical vibration parameters as well as methodology was used from a previous paper that was performed in conjunction with my thesis advisor on similar core samples. The experimentation was performed on five core samples with different porosities and …


Development Of An Electromagnetic System For Wireless Magnetic Manipulation Of Soft Capsule Endoscope For Drug Delivery Applications, Nada Ashraf Hussein Mahmoud Jan 2024

Development Of An Electromagnetic System For Wireless Magnetic Manipulation Of Soft Capsule Endoscope For Drug Delivery Applications, Nada Ashraf Hussein Mahmoud

Theses and Dissertations

Wireless capsule endoscopy (WCE) is a remarkable diagnostic device that examines the gastrointestinal (GI) tract. The WCE is a small capsule integrated with a camera that is used to visualize the inner mucosa of the GI tract. WCE has been proven to be the most effective method to diagnose GI diseases and GI cancers. The procedure reduces the discomfort and risk compared to conventional endoscopy methods. However, current WCEs lack the ability to take a biopsy or deliver a drug to a specific location. Those therapeutic functions can be introduced by wirelessly controlled WCEs. This thesis introduces an electromagnetic system …


A 3d Imaging-Based Critique Of Wire Arc Additive Manufacturing (Waam) Simulations, Omar Oraby Jan 2024

A 3d Imaging-Based Critique Of Wire Arc Additive Manufacturing (Waam) Simulations, Omar Oraby

Theses and Dissertations

Residual 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's 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 …


Improving The Energy Efficiency Of Residential Buildings In Egypt Through Whole Building Simulations, Habiba Aly Jan 2024

Improving The Energy Efficiency Of Residential Buildings In Egypt Through Whole Building Simulations, Habiba Aly

Theses and Dissertations

Residential buildings consume around 40% of total electricity consumption in Egypt. This research investigates the energy saving potential of the Green Pyramid Rating system (GPRS) and Tarsheed rating system on the building envelopes of mid-rise middle income residential buildings in Cairo through energy modelling and simulation. The study evaluates the economic feasibility of the recommendations of the two rating systems through Life Cycle Cost (LCC), Simple Payback Period (SPP), Discounted Payback Period (DPP), Net Present Value (NPV), and Internal Rate of Return (IRR) Calculations. This research also aims to develop energy efficiency recommendations to achieve 30% energy savings above the …


The Effect Of Mechanical Strain On The Electronic Conductivity Of Α- Fe2o3: A Density Functional Theory Study, Sheriff Naziru Abdulmutalib Jan 2024

The Effect Of Mechanical Strain On The Electronic Conductivity Of Α- Fe2o3: A Density Functional Theory Study, Sheriff Naziru Abdulmutalib

Theses and Dissertations

Hydrogen 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 …


Integrated Project Delivery (Ipd): A Contractual Framework For The Egyptian Construction Industry, Sarah Hussain Jan 2024

Integrated Project Delivery (Ipd): A Contractual Framework For The Egyptian Construction Industry, Sarah Hussain

Theses and Dissertations

This abstract highlight the significant findings and contributions of the study, which aimed to develop model clauses specifically tailored to the Egyptian construction industry for multi-party construction contracts. The research methodology encompassed several key components. Firstly, a comprehensive literature review was conducted to explore the various construction delivery methods prevalent in Egypt. This review provided a solid foundation for understanding the existing practices and identifying areas for improvement. The study also delved into the concept of Integrated Project Delivery (IPD) and its potential benefits as well as an analysis of the commonly used standard forms of contract and successful case …


Borophene And Graphene For Non-Enzymatic Biosensor- Ab-Initio Study, Omar A. Ismail Dec 2023

Borophene And Graphene For Non-Enzymatic Biosensor- Ab-Initio Study, Omar A. Ismail

Theses and Dissertations

Non-enzymatic glucose sensing holds promise to overcome limitations associated with glucose oxidase, such as oxygen dependence and short shelf life. This study explores the potential sensing capabilities of borophene and graphene through direct interaction with various compounds, including β-glucose, uric acid, ascorbic acid, fructose, and acetaminophen. Using Density Functional Theory (DFT), we calculated binding energies and the respective Density of States (DOS) for these adsorbates on both graphene and borophene surfaces. Preliminary results suggest that borophene might exhibit nearly twice the affinity for β-glucose compared to graphene. Moreover, the calculated Density of States reveals distinct distortions in the electronic states …


Fabrication & Characterization Of Hybrid Piezoelectric/Triboelectric Nanocomposite Nanogenerators Via Fusion Deposition Modeling, Khaled El Toukhy Dec 2023

Fabrication & Characterization Of Hybrid Piezoelectric/Triboelectric Nanocomposite Nanogenerators Via Fusion Deposition Modeling, Khaled El Toukhy

Theses and Dissertations

This thesis aims to discuss the potential of using piezoelectric and triboelectric nanogenerators (PTENGs) for energy harvesting, particularly in the sportswear industry. PTENG's main advantage is that it offers good flexibility making it suitable for high-strain applications. The piezoelectric effect is induced by embedding piezoelectric nanofillers into one of the two triboelectric layers. PTENGs can generate both piezoelectric and triboelectric signals when strained resulting in an enhanced output compared to regular piezoelectric nanogenerators (PENGs) and triboelectric nanogenerators (TENGs). TPU was adopted as the matrix for PTENGs advantageous due to their flexibility, low electrical resistivity, and compatibility with additive manufacturing techniques. …