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Item Advancements and Modification of 3rd Generation Solar Cells for Hydrogen Production(2024-09) Alashkar, Adnan; Ibrahim, Taleb; Alalami, Abdul HaiHydrogen is a clean and versatile energy carrier that can be used as a fuel in a variety of applications. Solar-driven hydrogen production via water electrolysis, utilizing third-generation solar cells, represents a sustainable and carbon-neutral approach to generate hydrogen. These advanced solar cells, namely dye-sensitized solar cells (DSSC) and perovskite solar cells (PSC), are prized for their high efficiency, cost-effectiveness, and potential to support sustainable energy initiatives. In addition, central to water electrolysis technologies are the electrodes catalysing the hydrogen evolution reaction (HER), with platinum (Pt) traditionally regarded for its superior catalytic activity. However, Pt limited availability and high cost hinder widespread deployment in commercial electrolysis systems. In this project, two approaches are examined on the path of enhancing the performance, stability, and cost of solar-driven hydrogen production. In the first approach, third generation solar cells are modified through enhancing the performance and figure of merit of DSSCs via utilizing transparent and conductive electrodes made of copper mesh and replacing metal-based sensitizers with natural dye. Ionic liquids (ILs) are employed as additives for bulk passivation of perovskite films which enhanced the stability and performance of PSCs by increasing the power conversion efficiency of the PSC by 2%. The modified third generation solar cells show great enhancement in the cost and performance of solar-driven hydrogen, where DSSCs and passivated PSCs showed an improved figure of merit by 0.05%/AED and 0.14%/AED, respectively when compared to silicon solar cells. In the second approach, Cu and Ni foams are augmented via adding a graphene layer to enhance the electrochemical kinetics of the HER. Graphene is synthesized and deposited employing the facile ball milling technique, thus reducing the time and cost involved in conventional graphene deposition methods. These modifications showcase promising performance of Cu and Ni foams that is comparable to Pt electrodes but at a reduced cost, highlighting their potential for advancing solar-driven hydrogen production technologies.Item Electronic and Magnetic Properties on Selected Transition Metal Alloys and Crystals(2024-11) Mustafa, Faisal; El-Khatib, Sami; Egilmez, MehmetItem Doxorubicin release and uptake from Trastuzumab and Folic acid liposomes with ultrasound(2024-12) AlSawaftah, Nour Majdi; Husseini, Ghaleb; Pitt, WilliamSmart drug delivery in cancer therapy, using surface-functionalized liposomes and triggers like ultrasound (US), helps minimize the side effects and enhance drug accumulation at tumor sites. This research investigated the effects of physically mixing Doxorubicin (DOX)-loaded liposomes decorated with folic acid (FA) and decorated with Trastuzumab (TRA) to treat breast cancer. It examined the US-mediated release of DOX from control, FA-modified, TRA-modified, and mixed FA and TRA liposomes at three different volume fractions. The size of the synthesized liposomes was found to be well within the range for the enhanced permeability and retention (EPR) effect to take place (<200 nm in diameter). The liposomes had a uniform lipid content and were stable under physiological conditions and at 4 °C. Moreover, the TRA conjugation was confirmed using the bicinchoninic acid (BCA) assay while the FA conjugation was established using nuclear magnetic resonance (HNMR). Then, DOX release using low-frequency ultrasound (LFUS) at 20 kHz and three power densities (6.2, 9, and 10 mW/cm²) and high-frequency ultrasound (HFUS) at 1 MHz and a power density of 2.5 W/cm² was examined. Mixed liposomes showed the best release performance in both LFUS- and HFUS-triggered conditions, with M75 liposomes showing the highest release using both LFUS and HFUS sonication. The LFUS and HFUS release data were fitted to three different kinetic models (zero-, first-, and second-order). The LFUS data was best fit by the zero-order model while the HFUS data was best fitted by the first-order model. In vitro uptake was studied using flow cytometry in FRα+ and HER2+ HCC-1954 breast cancer cells. The cells treated with the M25 group showed the highest cellular uptake with an 8.5-times increase compared to the control liposomes group when sonicated with LFUS. Similarly, the M25 group exposed to HFUS with microbubbles (MBs) enhanced DOX uptake by 10-times compared to the control liposomes. Finally, the cell viability of the developed formulations was assessed using the MTT assay. Physically mixed liposomes reduced the viability of sonicated cells more than individually targeted liposomes, especially the M25 group. These findings highlighted the potential of combining physically mixed liposomes and US to treat breast cancer.Item Surface Functionalized Medium Entropy Alloys for Electrochemical Hydrogen Production(2024-10) Ahmad, Shahbaz; Egilmez, Mehmet; Alnaser, AliThis thesis explores non-precious metal-based electrocatalysts, focusing on medium and high entropy alloys (HEAs) like CoCrNi, CoNiV, and CoNi(Cr/V) for the hydrogen and oxygen evolution reactions (HER and OER). These multi-principal element alloys utilize cost-effective transition metals, known for their robustness, corrosion resistance, and structural stability, and are systematically synthesized and characterized here. Analysis confirmed a stable, single-phase face-centered cubic (FCC) crystal structure in these alloys, while electrochemical testing showed that CoNi(Cr/V) achieved a notable overpotential of 50 mV at 10 mA/cm² and a Tafel slope of 48 mV/dec, highlighting its excellent catalytic performance for HER. To expand on this work, equiatomic thin films of NiCoCr, NiCoV, and NiCo(Cr/V) were created via magnetron sputtering. As bifunctional electrocatalysts, these films exhibited remarkable activity for alkaline water splitting, with the NiCo(Cr/V) film performing comparably to platinum-based catalysts (Pt/C) and showing resilience in both acidic and alkaline conditions. These properties make the NiCo(Cr/V) system a promising candidate for sustainable energy applications. Further, laser structuring applied to NiCo(Cr/V) thin films enhanced the electrochemical performance, with the laser-structured LS-NiCo(Cr/V) samples showing improved HER and OER metrics compared to unstructured samples. This finding highlights the value of laser processing in refining both surface properties and electrocatalytic function in medium entropy alloys.In summary, this research showcases the potential of multi-principal element alloys and surface structuring methods for cost-effective, high-performance electrocatalysts in water splitting applications. These innovations enhance the understanding of electrocatalytic mechanisms and pave the way for practical, sustainable hydrogen production solutions, supporting a shift toward cleaner and economically viable energy systems.Item Immunoliposomes with High-Frequency Ultrasound and Microbubble-Mediated Triggering for Herceptin-Positive Targeted Breast Cancer Therapy(2024-09) Abuwatfa, Waad Hussein; Husseini, Ghaleb; Pitt, WilliamItem An Integrated Decision Support System for BIM-level 3Implementation(2024-04) Abu-Moeilak, Lama S.M; Beheiry, SalwaItem Periodic Cellular Cores with Tailored Architectures for Improved Mechanical Properties(2024-09) Al Osman, Omar Abdulhadi; Alkhader, Maen; Abuzaid, WaelCellular solids, which include foams and lattice structures, exhibit uniquely high specific structural and thermal properties due to their porous structures, as well as their topological and morphological features. These properties make them attractive for various weight-sensitive applications in aerospace, automotive, and biomedical fields. This work aims to accelerate the use of cellular solids in engineering applications by enhancing their properties through tailoring their topological and morphological features. Multiple approaches were used in this work to enhance the mechanical and thermal properties of cellular solids. The first approach focused on coating metallic aluminum foams with copper to improve their properties. This research path employed both numerical and experimental techniques, including finite element analysis (FEA), electrodeposition, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and uniaxial quasi-static compression. Results showed that coating aluminum foam with 4% relative density with copper significantly enhances its stiffness and thermal conductivity. Improvements reaching 138% and 196% in stiffness and thermal conductivity were realized, respectively. Analytical models predicting the macroscopic stiffness, yield, and thermal conductivity of coated metallic foams were derived. These models are applicable to material systems other than the copper and aluminum system investigated, generalizing this work to assist engineers in designing hybrid coated metallic foams from a wide range of constituents compatible with electrodeposition. The second approach involved enhancing the mechanical properties of lattice structures by modifying their topology with sinusoidal perturbations. Numerical simulations were conducted to analyze the effects of these perturbations on the modified honeycomb's response to out-of-plane, in-plane, transverse shear, flexural loadings, and low-velocity impacts. Results showed that the sinusoidal perturbations can shift the failure mode from elastic buckling to yielding, increasing the peak load capacity by up to 28.5% under concentrated out-of-plane loads.Item Microstructures-Based Constitutive Modelling for Dynamic Strain Aging in Metal Alloys(2024-09) Hassan, Arhum; Abed, FaridItem Structural Behavior of Circular Columns Made of Ultra-High Performance Engineered Cementitious Composites (UHP-ECC)(2024-04) Elkafrawy, Mohamed; AlHamaydeh, MohammadItem Novel Sandwich Panel Design Integrating Structural Reinforcements with Polymeric Foam(2024-06) Charkaoui, Assil; Hussein, Noha; Bahroun, ZiedSandwich panels, with their exceptional strength-to-weight ratio and energy absorption capabilities, are indispensable in many engineering applications. However, enhancing their impact protection and crashworthiness is becoming more pronounced. This research investigates the synergistic effects of various core topologies and fillings to enhance energy absorption capacities. This involved exploring variations in the core structure by comparing different unit cell shapes (X-frame, octet strut, H-frame, I-frame, and rhombus) and topological features (core volume fraction, core height, number of core layers, and unit cell direction), analysing functionally graded sandwich panels, and studying different core fillers. The study examined different materials for core filling, such as resin, silicon, and foam. The resin core filler was also strengthened with CNT to improve performance. A comprehensive Design of Experiments (DOE) approach was employed to explore the synergistic effects of the different variables. Numerical experiments were conducted using ABAQUS/CAE based on the experimental setup of a drop tower test. Regression analysis was used to investigate the numerical model responses and develop regression equations. Optimization techniques were then used to determine the optimum design parameters that maximize energy absorption using GAMS software. The optimization results showed that the X- frame core in the transverse direction with a volume fraction of 20% and a total core height of 30 mm provides the best combination for increasing energy dissipated in damage and recoverable strain energy while minimizing the overall mass of the structure. Moreover, results demonstrated the foam’s ability to enhance energy absorption capabilities in X-frame sandwich panels. The optimal X-frame design was integrated with a foam filler, enhancing the energy absorption capabilities further. Additionally, the functionally graded core of the X-frame sandwich panels, graded in the x-axis from the most to the least number of unit cells across three layers, showed a significant increase in energy absorption. Although resin-filled sandwich panels exhibited a brittle nature, the addition of CNT prevented perforation and significantly decreased the damage area on the sandwich panel. This research contributes valuable insights into the design and optimization of sandwich panels for enhanced impact resistance.Item Assessment of bent and straight GFRP reinforcement conditioned in harsh environments(2024-06) Khalil, Ahmed Mohsen; Hawileh, Rami; Attom, MousaThis dissertation investigated the impact of durability on the strength of bent and straight GFRP rebars in harsh environments. The typical tensile strength observed in bent FRP rebars compared to the strength of straight rebars was on average lower by 40%, unlike conventional steel. There was a lack of studies on the durability of bent FRP bars in harsh environments like those in the UAE and Gulf region. To address this gap, two sets of durability tests were conducted, one indoors and another outdoors, with a specific focus on performance in saline environments. A comparative analysis was conducted among the results of control unconditioned samples, those exposed to the outdoor saline environment of the UAE, and those subjected to indoor accelerated durability setups in the laboratory. The aim was to identify any consistent patterns of strength deterioration in straight and bent GFRP rebars across these two testing setups (indoor and outdoor), as compared to control unconditioned specimens. The variables of the experimental program were GFRP rebar diameter, manufacturer, rebar shape, radius of curvature, durability setup, and aging duration. The results covered failure modes, load-deflection responses, strain measurements, tensile strength retention, and microstructure analysis of the GFRP rebars. Test results showed that GFRP rebars, whether straight or bent, demonstrated similar initial stiffness. However, load capacity and deflection variations were observed based on rebar size and exposure conditions. The microstructure analysis through SEM showed that the manufacturing bending process changed the cross-section of GFRP rebars from circular to approximately rectangular, which altered the load distribution and induced differential stresses along the rebar length. Additionally, environmental exposures caused notable fiber and fiber-matrix interface damage in the GFRP rebars. This study concluded that there was moderate retention of tensile strength, with an average of about 80% for the outdoor setup and 75% for the indoor accelerated setup over the exposure periods. Thus, nonmetallic GFRP reinforcement was a viable alternative to steel reinforcement in RC structures exposed to marine and harsh saline environments.Item A Policy Management Framework to Mitigate the Impacts of Building Construction on Urban Climate(2024-03) Almashhour, Ragad; Kolo, JerryThe construction industry is the largest and fastest growing industry in the world for reasons such as population increase, rising standards of living, and the constant demand for infrastructure. Buildings are a category of infrastructure and a major source of greenhouse gas (GHG) emissions. Directly and or indirectly, therefore, buildings make cities warmer, turn cities into urban heat islands (UHI), and contribute to the climate crisis. There is currently no discernable strategic policy and management approach in the extant literature and in practice, which municipalities worldwide use to permit or approve buildings based on the heat or GHG they emit into the atmosphere. This purpose is not served by the various existing voluntary compliance environmental audit systems. Unanimity on the impacts of buildings on urban microclimate requires that cities take decisive measures to address how buildings make cities hotter. In this light, this dissertation aims to draw on the technical and experiential knowledge of construction experts, professionals, and key actors, in order to formulate a policy and management framework that municipalities can use to mitigate the impacts of construction on climate change. The research employed a hybrid method consisting of the Delphi Technique and Confirmatory Factor Analysis (CFA) to identify the main structural building factors that contribute to the UHI. Quantitative and qualitative data were collected and analyzed in order to answer the research questions and achieve the research aim and objectives. The research also resulted in the design of a dynamic framework which municipalities worldwide can use to approve buildings based on their propensity to emit heat into the atmosphere. The framework is versatile and adaptable to local contexts worldwide. The research fills an environmental audit gap in the construction industry; contributes to research discourse on climate change; and, most importantly, provides municipalities with a pragmatic and cost-effective policy tool to address the challenges of UHI.Item The Impact of Poor Communication During the Pandemic Situation Within the UAE Real Estate Sector(2024-04) Al-Ustad, Mohammed Ibrahim Mustafa; Ahmed, Vian; Alshraideh, HussamReal estate is one of the most fundamental industries in the global economy. The research highlighted that poor communication is core to the project's failure. In addition, despite the literature listing numerous studies and credible scales that have been proposed over the years with information linking poor communication in construction projects, they frequently focus only on the project team and the execution stage in the third phase of the project life cycle. Moreover, there was little or no information about real estate project failure between the stakeholders. There were no defined factors of poor communication in each stage of the real estate industry's project life cycle during the pandemic research was conducted. No tool was developed to solve the issue of poor communication between the stakeholders during the project life cycle in the UAE during a pandemic, which indicates a research gap. To fill this gap, the research defines poor communication between the stakeholders throughout the project life cycle. The study focuses on finding additional factors that cause poor communication from the interviews with the stakeholders, which contribute to the finding of 58 new factors. Hence, CFA identified the most significant factor in the project life cycle, which is around 34 factors. The research developed a decision tree tool that can predict poor communication and the factors contributing to a particular stage in a real estate project. The decision support tool protects the project from any failure due to time and cost overruns supported by the risk matrix. Lastly, the study creates an application platform that will be adopted by project management in the real estate industry to test poor communication in each stage of the project life cycle in UAE during the pandemic situation. In conclusion, the research fulfills the literature review gap by developing a decision support tool that predicts the occurrence of poor communication in the real estate industry and identifies the factors that impact poor communication based on historical data in real estate during the project life cycle.Item An Investigation of Health Impacts of Transportation Planning: A Framework Development and Simulation-Based Results(2024-04) AlQahtani, Mohamed Tarish; Abu-Lebdeh, GhassanItem A Machine Learning Model Based Schedule of Photovoltaic Solar Plant Dust Cleaning(2024-03) Abuzaid, Haneen Mohammad Faleh; Awad, Mahmoud; Shamayleh, AbdulrahimItem A Framework for Peer-to-Peer (P2p) Electricity Trading in Distribution Networks(2024-05) Al Marzooqi, Ahmed Hassan ; Osman, Ahmed; Shaaban, MostafaThe introduction of the Smart Grid has resulted in many applications that have been developed and followed the concept of bidirectional flow of electricity and data. One of the pillars of smart grids is the distributed generation (DG) technologies, where the customers turn to be prosumers with power generation capability. Another pillar is demand side management (DSM), which helps in controlling the energy consumption by changing the power usage slots among other peers. DG and DSM have facilitated the sharing of excess power by customers to the grid, and then to their peers through the grid as a trading agent. Although the concept of peer-to-peer (P2P) energy trading integrated with DSM has been explored by scholars and relative trading frameworks have been established, there is very limited research on the impact of power quality (PQ) and supply reliability (SR) on electricity transactions. The aim of this study is to explore the perception of P2P electricity trading within the Power Distribution Network in the United Arab Emirates and to build a Peer-to-Peer energy trading framework considering power quality and supply reliability. The proposed study will encounter the reliability performance of the participants, minimize the power quality impact, and manage the energy management system using game theory. The customer perception and satisfaction level with the quality of supply evolving energy trading have been explored and results were discussed in the study. The proposed P2P framework resulted in reduction of the trading cost through applying a profit sharing scheme and using reliability pricing scheme, and provides a foundation base to the utilities as well as individuals to the changes in the electricity market structure with new business opportunities for the utilities.Publication Detection of Traffic Incidents Using Machine Learning Techniques(2023-04) ElSahly, Osama Mohamed; Abdelfatah, AkmalThis dissertation proposes new models for detecting traffic incidents on freeways using machine learning algorithms to classify traffic data collected from the freeway system. These models are generic and consider multiple factors that affect incident detectability simultaneously. The models were trained and tested on simulated traffic data that represent normal and incident conditions using the well-known microsimulation software VISSIM. The proposed models, which include the Random Forest (RF) and Multilayer Feedforward Artificial Neural Network (MLF), consider four factors: the congestion level, the distance between the upstream and downstream detector stations, the location of the incident relative to the detector stations, and the severity of the incident. The results showed that the developed models achieved excellent performance, surpassing existing models in the literature. During training, the MLF model achieved a detection rate (DR) of 95.96%, a mean time to detect (MTTD) of 0.89 minutes, and a false alarm rate (FAR) of 1.01%. During testing, the MLF model achieved a DR of 100%, MTTD of 1.6 minutes, and FAR of 1.29%. Similarly, the RF model achieved a DR of 96.97%, MTTD of 1.05 minutes, and FAR of 0.62% during training, and a DR of 100%, MTTD of 1.17 minutes, and FAR of 0.862% during testing. The results revealed that incident detection systems may have difficulty detecting incidents with minor severity during low traffic volumes. The FAR decreased with the increase in the Demand to Capacity ratio (D/C), while the MTTD increased with the increase in D/C. Additionally, higher incident severity resulted in lower MTTD values, while the distance between the incident location and upstream detector had the opposite effect. The FAR decreased as the incident moved farther from the upstream detector but increased with the distance between detectors. Larger detector spacings were associated with longer detection times. The proposed models can significantly improve traffic performance on freeways, especially during incidents, and benefit both local and international transportation agencies. The study's contribution lies in developing efficient and reliable incident detection models that consider multiple variables simultaneously, improving traffic safety, reducing congestion, saving lives and properties, and reducing pollution.Publication Decision Support Model for Selecting the Project Delivery Method for Sustainable Construction Projects(2023-03) Ahmed, Salma Nasser Korany Megahed; El-Sayegh, SamehAs the demand for sustainable construction increases, the need to update project management practices in order to satisfy the objectives of sustainability becomes more significant. Project delivery method is a crucial decision in project management that impacts the success of construction projects. The extensive literature review conducted identified several gaps such as the lack of a comprehensive criteria list to select project delivery methods in sustainable construction projects and a lack of selection model that comprises that comprehensive criteria list. This research bridges the gaps in literature by developing a comprehensive decision support model that will provide decision-makers with a justified rationale for choosing the most appropriate delivery method for their sustainable construction projects. In order to achieve this, the underlying challenges of sustainable construction delivery were first categorized using factor analysed. These were then used to derive relevant sustainability -specific criteria which consisted of five groups: level of integration, green liability, green team, green criteria, and technology and innovation. Structural Equation Modelling was then used to predict the significance of these sustainability-specific selection criteria to the achievement of project success criteria such as efficiency, impact on client, team effectiveness and sustainability. Moreover, Analytical Hierarchy Process was used to calculate the relative weights of the traditional and sustainability-specific criteria as well as the effectiveness values of the three most common delivery methods in achieving the comprehensive criteria. The outputs of all these statistical procedures were then used to develop two decision support models that incorporate a comprehensive selection criteria list of both traditional and sustainability-specific criteria and the three most common delivery methods. Moreover, a customizable prototype software of the decision model was developed where the unfamiliar operations required in the adopted technique would be transparent to the end-users. A case-study that was administered in the end clearly indicates that DBB is outmatched by the unique requirements of sustainable construction. While, CMR and DB are both potentially competitive candidates that can enhance the success rate of sustainable construction projects.Publication Routing of Hybrid Truck-Drone Delivery Systems: Mathematical Models and Solution Approaches(2023-03) Madani, Batool Mezar; Ndiaye, MalickPublication Maintenance and Sustainability: Decision Support Tools and Role of Maintenance Digital Transformation(2023-03) Saihi, Afef; Ben-Daya, Mohamed; As'ad, RamiMaintenance is a crucial activity conducted throughout the use phase of the engineered object life cycle, which has tremendous impact on all three pillars of sustainability. While economic and technical impacts of maintenance activities are well-studied and vastly addressed in the literature, the associated impacts on environmental and social pillars are not sufficiently tackled. As such, maintenance-related decisions, in all its facets, have been mostly driven by these economic and technical measures. Full integration of sustainability considerations into maintenance practices requires close monitoring and assessment of maintenance impact on the triple-bottom-line through relevant key performance indicators (KPIs) and appropriate decision-support tools that take into account pertinent sustainability issues. To that end, there is a need for further research concerning the integration of all sustainability aspects into maintenance practices along various directions, including (1) developing adequate and relevant KPIs, (2) proposing models for accurate maintenance sustainability performance evaluation, (3) exploring the role of technology in enabling this integration, and (4) devising sound decision-making tools. Therefore, this research addresses the existing gaps and aims to develop effective tools for integrating sustainability aspects into maintenance decisions practices, and to explore the challenges that hinder this integration and the potential role of technology in overcoming them. First, a comprehensive and hierarchical framework of sustainable maintenance performance indicators is developed and validated by experts in the field. Using this framework as a guide, a fourth-order Partial Least Square-Structural Equation Modeling (PLS-SEM) based higher component model for measuring sustainable maintenance performance is proposed and validated in the Oil and Gas industry. Furthermore, given that digital transformation (DT) of maintenance can play a pivotal role in facilitating the integration of sustainability issues in maintenance decision-making, it is crucial to identify the key ingredients and the most influencing factors, beyond purely technological aspects, that drive the success of digitalization efforts. Then, a hybrid reactive Delphi approach is adopted to identify and validate the key factors driving the success of maintenance DT and aiding its implementation. Finally, a first-step is taken towards proposing planning models that integrate sustainability in the decision-making process.