AUS Repository (American University of Sharjah)
Not a member yet
2669 research outputs found
Sort by
INScription: Department of International Studies (INS) Issue #20 (February 29, 2024, Issue 6)
No full textCollege of Arts and SciencesDepartment of International Studie
A Bayesian Approach to Feature Selection in Classification Problems
No full textA Master of Science thesis in Mathematics by Maher Emarly entitled, “A Bayesian Approach to Feature Selection in Classification Problems”, submitted in July 2024. Thesis advisor is Dr. Ayman Alzaatreh. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).The exponential growth of data, as well as the widespread use of machine learning in daily life, demonstrate the importance of feature selection. Feature selection, defined as the process of identifying and selecting a subset of relevant features from a larger set of available features, is a crucial step in machine learning. The performance and efficiency of machine learning models are improved by focusing on the most informative features and eliminating unnecessary or redundant ones. Furthermore, model interpretability is enhanced, resulting in clearer insights and an actionable understanding of the results. The resulting models are more robust, less prone to noise, and can be efficiently trained and deployed, ultimately contributing to more effective and efficient data-driven decision-making processes. We propose a Bayesian approach using the relative belief ratio (RBR) as a filter method in this paper. The proposed method showed an excellent performance in binary and multiclass classification problems. In addition, the proposed method generates a strength value that can be used as an importance score for each feature. The numerical value of the strength of the RBR is used to rank the features. This method aims to discern the relative importance of features concerning a target variable and test for their significance. The proposed method’s performance is evaluated using both synthetic and real-world datasets, and it is compared to various popular filter methods.College of Arts and SciencesDepartment of Mathematics and StatisticsMaster of Science in Mathematics (MSMTH
Modifying cellulose fibres with carbon dots: a promising approach for the development of antimicrobial fibres
No full textThis study focuses on the development of antimicrobial fibres for use in medical and healthcare textile industries. Carbon dots (CDs) were designed with boronic acid groups for the attachment to cellulose fibres found in cotton textiles and to enhance their attachment to glycogens on bacterial surfaces. Boronic acid-based and curcumin-based CDs were prepared and characterized using various techniques, showing a nanoscale size and zeta potential values. The CDs inhibited the growth of both Staphylococcus epidermidis and Escherichia coli bacteria, with UV-activated CDs demonstrating improved antibacterial activity. The antimicrobial activity of the CDs was then tested, revealing strong adherence to cellulose paper fibres with no CD diffusion and potent inhibition of bacterial growth. Cytotoxicity assays on human cell lines showed no toxicity towards cells at concentrations of up to 100 µg ml−1 but exhibited increased toxicity at concentrations exceeding 1000 µg ml−1. However, CD-modified cellulose paper fibres showed no toxicity against human cell lines, highlighting the antimicrobial properties of the CD-modified cellulose fibres are safe for human use. These findings show promising potential for applications in both industrial and clinical settings.American University of Sharja
Global Sensitivity and Uncertainty Analysis of Asymmetric Bistable Energy Harvesters
No full textThis study investigates the performance of asymmetric bistable energy harvesters with nonlinear piezoelectric coupling, focusing on the impact of parametric variability on system reliability. Global sensitivity analysis using Sobol indices identifies critical parameters influencing harvested power, providing insights for the robust design of nonlinear harvesters. To address uncertainties in system parameters, we employ a probabilistic framework incorporating Polynomial Chaos Expansion (PCE) and probabilistic maps. This approach, leveraging the maximum entropy principle, models and propagates uncertainties to visualize their effects on power output. Results show that excitation frequency, amplitude, asymmetric terms, and piezoelectric coupling properties are critical factors, with their importance varying across dynamic stability regimes. Our findings highlight the need to account for joint parameter variability to enhance energy harvesting system efficiency and reliability
Severed Nerve Reconnection: Designing an Integrated System for Enhanced Neural Recording
No full textA Master of Science thesis in Biomedical Engineering by Malak Mohammad Mneimneh entitled, “Severed Nerve Reconnection: Designing an Integrated System for Enhanced Neural Recording”, submitted in December 2024. Thesis advisor is Dr. Lutfi Al-Basha. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).College of EngineeringMultidisciplinary ProgramsMaster of Science in Biomedical Engineering (MSBME
Development of a Machine Learning Based Smart Water Leak Detection System
No full textA Master of Science thesis in Civil Engineering by Rabab Al Hassani entitled, “Development of a Machine Learning Based Smart Water Leak Detection System”, submitted in December 2024. Thesis advisor is Dr. Md. Maruf Mortula AND thesis co-advisor is Dr. Tarig Ali. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE
Linearization of 5G dual-band power amplifiers
No full textA Master of Science thesis in Electrical Engineering by Majid Faroug Eltayeb Ahmed entitled, “Linearization of 5G dual-band power amplifiers”, submitted in December 2024. Thesis advisor is Dr. Oualid Hammi. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).College of EngineeringDepartment of Electrical EngineeringMaster of Science in Electrical Engineering (MSEE
Effect of increasing the number of anchors on the flexural performance of FRP-strengthened RC beams
No full textFiber-reinforced polymers (FRP) have been extensively used in external strengthening and retrofitting of existing reinforced concrete (RC) structures. Beams strengthened with FRP sheets exhibit improved performance in terms of flexural capacity. However, the ductility of the beams is sacrificed due to the brittle failure of externally bonded FRP sheets in the form of FRP debonding or concrete cover delamination. Spike anchorage systems were developed to prevent or mitigate debonding of FRP sheets in externally strengthened RC beams. This study aims to investigate the effect of increasing the number of FRP spike anchors at the laminate's ends on the flexural behavior of strengthened and anchored RC beams. Three concrete beams having a length, depth, and width of 2000, 250, 200 mm, respectively, were tested under a four-point bending test. The first beam was strengthened and unanchored, and the other two beams were strengthened and anchored with one or two 14-mm diameter FRP anchors on each side, respectively. Results showed that increasing the number of anchors significantly improved the flexural behavior of the strengthened beam in terms of the beam's response at failure and the strain utilized in the FRP laminates. The strain utilization percentages as reported in the tested beams were 27%, 61%, and 99%, for the control unanchored, anchored with two anchors, and anchored with four anchors, respectively. Thus, it can be concluded that anchoring FRP sheets with two anchors at the laminate's ends if feasible is more effective than one anchor in delaying debonding failure, and thus would lead to a better enhancement in the flexural performance of strengthened RC beams
Review of Gold Nanoparticles: Synthesis, Properties, Shapes, Cellular Uptake, Targeting, Release Mechanisms and Applications in Drug Delivery and Therapy
No full textThe remarkable versatility of gold nanoparticles (AuNPs) makes them innovative agents across various fields, including drug delivery, biosensing, catalysis, bioimaging, and vaccine development. This paper provides a detailed review of the important role of AuNPs in drug delivery and therapeutics. We begin by exploring traditional drug delivery systems (DDS), highlighting the role of nanoparticles in revolutionizing drug delivery techniques. We then describe the unique and intriguing properties of AuNPs that make them exceptional for drug delivery. Their shapes, functionalization, drug-loading bonds, targeting mechanisms, release mechanisms, therapeutic effects, and cellular uptake methods are discussed, along with relevant examples from the literature. Lastly, we present the drug delivery applications of AuNPs across various medical domains, including cancer, cardiovascular diseases, ocular diseases, and diabetes, with a focus on in vitro and in vivo cancer research.Dana Gas Endowed Chair for Chemical EngineeringAmerican University of SharjahSheikh Hamdan Award for Medical SciencesFriends of Cancer Patient
Behavior of Slender Circular Columns Made of Fiber-Reinforced Green Concrete and Hybrid Steel-GFRP Reinforcement
No full textA Master of Science thesis in Civil Engineering by Nouran Hegazy entitled, “Behavior of Slender Circular Columns Made of Fiber-Reinforced Green Concrete and Hybrid Steel-GFRP Reinforcement”, submitted in August 2024. Thesis advisor is Dr. Mohammad AlHamaydeh Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).The inherent issue of steel corrosion in reinforced concrete structures has elicited the need to find viable alternatives. Glass Fiber-Reinforced Polymer (GFRP) bars have emerged as a competitive alternative to steel reinforcement owing to their superior properties, such as being noncorrodible, non-magnetic, and possessing a high strength-to-weight ratio. Nonetheless, owing to their low modulus of elasticity and low compressive strength, the currently available FRP RC design codes, such as ACI 440.11-22 and CSA S806-12, neglect the contribution of FRP bars to the columns’ ultimate capacities. Another sustainable construction material employed in this study is green concrete, made with ground granulated blast-furnace slag (GGBS), as an alternative to conventional concrete. The concrete mix is complimented by the addition of synthetic fibers to enhance crack control, material durability, and overall capacity. The combination of these materials promotes sustainable RC construction with a competitive performance. This study presents the analysis of experimental tests conducted on full-scale slender circular reinforced concrete columns made with fiber-reinforced green concrete and reinforced with a novel double-layer hybrid arrangement of steel and GFRP bars, subjected to concentric and eccentric loading. In addition, a control group of full-scale steel RC columns are tested. All specimens had constant longitudinal reinforcement and transverse reinforcement ratios. The key design parameters investigated were the longitudinal reinforcement type (steel and GFRP bars), loading eccentricity (e/h = 0, 9.6%, 28.8% and 48.1%), transverse reinforcement type (steel and GFRP spirals) and reinforcement configuration (single and double layers). The results showed that hybrid steel-GFRP RC columns have similar overall compression behavior to their steel RC counterparts. However, the axial capacity of hybrid specimens was on average 30% to 60% lower than their steel RC counterparts. Moreover, hybrid RC columns showed slightly higher ductility than steel RC columns at all loading eccentricities, with calculated average ductility indices of 21.9 and 18.6, respectively. Nonetheless, the contribution of GFRP bars in compression to the ultimate capacities of the columns was around 15% as compared to 60% for steel bars. Furthermore, the experimental load capacities of the columns are compared to theoretical predictions based on analytical equations available in the literature.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE