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Mathematical Modeling of Pediatric Leukemia: Logical Modeling Approach
No full textA Master of Science thesis in Mathematics by Valery Lacoste entitled, “Mathematical Modeling of Pediatric Leukemia: Logical Modeling Approach”, submitted in May 2024. Thesis advisor is Dr. Abdul Salam Jarrah. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Cancer is considered a world health issue, especially for children. Currently, cancer is the second leading cause of death in the United States and leukemia is the second leading cause of cancer death among children and adolescents younger than 20. B-cell acute lymphoblastic leukemia is a type of blood cancer that affects the body’s immune system and creates immature B-cells that no longer fulfill their designated role. Numerous biological studies have tried to understand this disease and suggest possible treatment strategies. So far these methods have limitations and give mixed results. Mathematical models have recently been used to shed some light on the complexities of cancer and develop a mechanistic understanding of the cancer processes, in particular logical network models have recently been developed to study the development of cancer cells and their interactions with their environment. In this thesis, a discrete logical network model is constructed to study the gene regulatory network in pediatric B-cells with a focus on the genes that are known to play a key role in pediatric acute lymphoblastic leukemia. The dynamics of the model is analyzed and used to suggest hypotheses and predictions.College of Arts and SciencesDepartment of Mathematics and StatisticsMaster of Science in Mathematics (MSMTH
Variable Selection in Data Analysis: A Synthetic Data Toolkit
No full textVariable (feature) selection plays an important role in data analysis and mathematical modeling. This paper aims to address the significant lack of formal evaluation benchmarks for feature selection algorithms (FSAs). To evaluate FSAs effectively, controlled environments are required, and the use of synthetic datasets offers significant advantages. We introduce a set of ten synthetically generated datasets with known relevance, redundancy, and irrelevance of features, derived from various mathematical, logical, and geometric sources. Additionally, eight FSAs are evaluated on these datasets based on their relevance and novelty. The paper first introduces the datasets and then provides a comprehensive experimental analysis of the performance of the selected FSAs on these datasets including testing the FSAs’ resilience on two types of induced data noise. The analysis has guided the grouping of the generated datasets into four groups of data complexity. Lastly, we provide public access to the generated datasets to facilitate bench-marking of new feature selection algorithms in the field via our Github repository. The contributions of this paper aim to foster the development of novel feature selection algorithms and advance their study.American University of Sharja
Advanced Thermal Management in Intermittent Electronics: Integrating Metal Foam and Phase Change Materials
No full textA Master of Science thesis in Mechanical Engineering by Muhammad Ahmad entitled, “Advanced Thermal Management in Intermittent Electronics: Integrating Metal Foam and Phase Change Materials”, submitted in December 2024. Thesis advisor is Dr. Mohammad O. Hamdan and thesis co-advisor is Dr. Bassam Abu-Nabah. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).The present work investigates the thermal performance and optimization of heat sinks for electronic applications using a metal foam, with different porosity and phase change material (PCM). The study examines various design parameters, such as PCM types (RT31, RT42, and RT55), different metal foam porosities (0.1, 20, 40, 60, 80, 90 and 95%), different foam materials (aluminum and copper), different levels of permeability (10⁻⁸, 10⁻¹⁰, and 10⁻¹²), and different heat fluxes(1000, 2000, 4000, and 8000 W/m²). The problem is numerically analyzed using ANSYS-fluent which is a commercial finite volume software. The objective of the study is to optimize the heat sink model for critical temperature ranges of 60−80°C while enforcing Boussinesq approximation. Results indicate that utilizing a porous metal foam with PCM enhances the heat sink efficiency by improving heat transfer with increased porosity leading to a significant improvement in thermal performance. Heat sinks infused with RT55 exhibit superior thermal performance compared to those with RT42 and RT31. This is due to its higher melting point, which allows it to remain solid for longer periods of heat application. While permeability and gravity had resulted in a negligible effect on the performance RT55 infused with 95% porous copper foam emerged as the best-performing combination, optimizing thermal energy storage for applications in passive heat sinks. Further analysis evaluated the melting times of RT55, RT42, and RT31 across various porosities, revealing that higher porosity generally results in longer melting times due to the larger PCM volume acquiring more time to absorb heat. Additionally, the selection of PCM type significantly influences the thermal performance, with RT31 consistently outperforming RT55 and RT42. The choice of foam material has rendered a significant effect on heat transfer efficiency, it is essential to note that the size of the heat sink can also impact the effectiveness of different metal foam types. Larger heat sinks may benefit from specific foam geometries or materials that enhance thermal conduction and fluid flow dynamics, thereby optimizing performance. Furthermore, varying heat flux levels and Boussinesq effects provide insights into real-world applications. The study also highlights the importance of optimizing these factors for the effective management of cooling systems.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
Advancements of MXene Based Nanocomposites as an Efficient Electrode Materials
No full textA Doctor of Philosophy Dissertation in Materials Science and Engineering by Anum Iqbal entitled, “Advancements of MXene Based Nanocomposites as an Efficient Electrode Materials”, submitted in November 2024. Dissertation advisor is Dr. Nasser M. Hamdan. Soft copy is available (Dissertation, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Recent technologies for efficient energy conversion and storage purposes are acknowledged as realistic remedies for upcoming energy shortages. However, the high cost and limited efficiency of electrocatalysts provide an obstacle to the practical application of these technologies. Therefore, improving the performance of these electrocatalytic materials is essential to expand their uses. Transition metal hydroxides and oxides show high activity and stability in alkaline electrolytes, are potential substitutes for expensive and rare metal oxides that include Ruthenium/Iridium oxides Nonetheless, these materials have intrinsic difficulties that limit their scalability, including low stability, ineffective conduction, and a low number of active sites. On the other hand, a new class of two-dimensional materials called MXenes has a unique combination of hydrophilicity, high electrical conductivity, and tunable surface-active sites that make them attractive preference for electrocatalyst applications. Nevertheless, MXene sheets are highly susceptible towards oxidation and self-stacking phenomenon that considerably diminish their electrical conductivity and stability in aquatic conditions under high voltages. Fortunately, it has been demonstrated that adding MXenes to other materials has synergistically increased the electrocatalytic activity of the resultant composites. In the first experimental plan of this thesis, a novel combination of TiO₂ electrodes functionalised with Ti₃C₂Tₓ MXene was fabricated in order to boost the performance of photoelectrodes by improving photon absorption, charge segregation, and photocurrent production at the electrode surface. In the second investigation, the eximious activity and stability of tri-metal hydroxides for improved OER activity was successfully achieved by immobilizing the active sites at open pores of three-dimensional (3D) V₂C MXene architecture. The morphologically unique V₂C MXene substrate modulated the structural and compositional features of the synthesized composite for highly accessible active sites and improved charge transfer. The results achieved in this thesis interestingly justify the role of MXene for development of efficient electrode materials for energy related applications.College of Arts and SciencesMultidisciplinary ProgramsPhD in Materials Science and Engineering (PhD-MSE
Investigating the Effect of Patient-Related Factors on Computed Tomography Radiation Dose Using Regression and Correlation Analysis
No full textComputed tomography (CT) is a widely utilized diagnostic imaging modality in medicine. However, the potential risks associated with radiation exposure necessitate investigating CT exams to minimize unnecessary radiation. The objective of this study is to evaluate how patient-related parameters impact the CT dose indices for different CT exams. In this study, a dataset containing CT dose information for a cohort of 333 patients categorized into four CT exams, chest, cardiac angiogram, cardiac calcium score and abdomen/pelvis, was collected and retrospectively analyzed. Regression analysis and Pearson correlation were applied to estimate the relationships between patient-related factors, namely body mass index (BMI), weight and age as input variables, and CT dose indices, namely the volume CT dose index (CTDIvol), dose length product (DLP), patient effective dose (ED) and size-specific dose estimate (SSDE), as output variables. Moreover, the study investigated the correlation between the different CT dose indices. Using linear regression models and Pearson correlation, the study found that all CT dose indices correlate with BMI and weight in all CT exams with varying degrees as opposed to age, which did not demonstrate any significant correlation with any of the CT dose indices across all CT exams. Moreover, it was found that using multiple regression models where multiple input variables are considered resulted in a higher correlation with the output variables than when simple regression was used. Investigating the relationships between the different dose indices, statistically significant relationships were found between all dose indices. A stronger linear relationship was noticed between CTDIvol and DLP compared to the relationships between each pair of the other dose indices. The findings of this study contribute to understanding the relationships between patient-related parameters and CT dose indices, aiding in the development of optimized CT exams that ensure patient safety while maintaining the diagnostic efficacy of CT imaging.Open Access Program from the American University of Sharja
Enhanced Deep Fusion Filter for Low-Cost INS/GPS Integration
No full textA Master of Science thesis in Mechatronics Engineering by Mohamed Ismail Abdelghani entitled, “Enhanced Deep Fusion Filter for Low-Cost INS/GPS Integration”, submitted in April 2024. Thesis advisor is Dr. Mohammad Jaradat and thesis co-advisor is Dr. Mamoun Abdel-Hafez. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).College of EngineeringMultidisciplinary ProgramsMaster of Science in Mechatronics Engineering (MSMTR
Recent Advancements in Bone Tissue Engineering: Integrating Smart Scaffold Technologies and Bio-Responsive Systems for Enhanced Regeneration
No full textIn exploring the challenges of bone repair and regeneration, this review evaluates the potential of bone tissue engineering (BTE) as a viable alternative to traditional methods, such as autografts and allografts. Key developments in biomaterials and scaffold fabrication techniques, such as additive manufacturing and cell and bioactive molecule-laden scaffolds, are discussed, along with the integration of bio-responsive scaffolds, which can respond to physical and chemical stimuli. These advancements collectively aim to mimic the natural microenvironment of bone, thereby enhancing osteogenesis and facilitating the formation of new tissue. Through a comprehensive combination of in vitro and in vivo studies, we scrutinize the biocompatibility, osteoinductivity, and osteoconductivity of these engineered scaffolds, as well as their interactions with critical cellular players in bone healing processes. Findings from scaffold fabrication techniques and bio-responsive scaffolds indicate that incorporating nanostructured materials and bioactive compounds is particularly effective in promoting the recruitment and differentiation of osteoprogenitor cells. The therapeutic potential of these advanced biomaterials in clinical settings is widely recognized and the paper advocates continued research into multi-responsive scaffold systems.American University of Sharja
The Application Of Game-Based Learning In Construction Management
No full textA Master of Science thesis in Construction Management by Yara Ashraf Farouk Moussa Elenany entitled, “The Application Of Game-Based Learning In Construction Management”, submitted in May 2024. Thesis advisor is Dr. Vian Ahmed. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).As the construction industry heads towards the Fourth Industrial Revolution, the gap widens between industry demands and fresh graduate capabilities. In today’s fast-paced digital age, there are three key industry needs for construction managers: strong theoretical understanding, adept technical skills, and transferrable soft skills. However, the existing traditional Construction Management (CM) pedagogy struggles to meet industry demands and student expectations regarding the development of transferrable soft skills. Experiential learning offers a great advantage to students in CM education to develop and exercise transferrable skills as well as allow them to construct meaningful knowledge based on their own experiences and at their own pace. Game-Based Learning (GBL) is a practice under Experiential Learning Theory (ELT) that uses simulation & gaming environments. While previous efforts have brought valuable insights for GBL in CM pedagogy, there still remains gaps in this research field. This thesis focuses on filling one gap, which is the lack of studies on digital games simulating the challenges of resource management. The aim of this study is to develop and evaluate a digital simulation game as a complementary teaching tool to reinforce CM students’ understanding of resource management and enhance their transferrable skills primarily decision-making and problem-solving.College of EngineeringMultidisciplinary ProgramsMaster of Science in Construction Management (MSCM
Life Cycle Assessment of Piezoelectric Materials Used for Energy Harvesting Systems: PZT Versus KNN
No full textOver the past decade, piezoelectric materials have been extensively used in various engineering areas, particularly for energy harvesting, due to their efficient electromechanical conversion. Several scientific researches reported in the literature have performed modeling, prototyping, and experimentation to improve the performance of harvesters. Piezoelectric transducers, especially those used for energy harvesting, could have significant environmental impacts. Few studies have emphasized the environmental issue of harvesters in their life cycle. This paper aims to study the environmental impacts of piezoelectric energy harvesters obtained with screen-printing process by performing a life cycle assessment (LCA). Firstly, a comprehensive overview of piezoelectric materials and their implementation in the context of micro electromechanical systems is first presented. Secondly, the environmental impacts of these materials are briefly discussed based on previous studies. Here the aim is to present a comparative analysis of the environmental consequences of energy harvesters based on different piezoelectric materials, from cradle to gate. The harvester based on lead zirconate titanate Pb(Zr,Ti)O₃ (PZT) is taken as a reference. The impact assessment is conducted by evaluating the selected impact categories using ILCD 2011 method. Results highlight the most impactful components of energy harvesters referring to the unique scores calculated for different impact categories at the Midpoint. They highlight also the importance of LCA and offer technical guidance and crucial recommendations for eco-design