Digital Commons Network^™

Development Of Guidance, Navigation, And Control Systems For Multi-Spacecraft Assembly In Proximity Operations, Mohammed Ayman Atallah

Theses

This thesis presents the development of Guidance, Navigation, and Control (GNC) algorithms for multi-spacecraft assembly in proximity operations. A 3-DOF mathematical model of spacecraft relative translational motion is derived using the Euler-Lagrange method. Additionally, a 6-DOF mathematical model of spacecraft relative translational and rotational motion is derived using the twistor method, with consideration for the kinematic coupling effect. A new Linear Time-Invariant (LTI) model is developed based on the twistor model, which is utilized in the design of the GNC systems. Both LTI Model Predictive Control (MPC) and Linear Time-Varying (LTV) MPC algorithms are employed to develop Guidance and Control …

Experimental Study Of Central And Side Jet With And Without Chevron Nozzle Exit On Gas Turbine Leading Edge Jet Impingement Cooling, Ahmad Yousef Alqasrawi

Theses

This thesis presents a comprehensive investigation into the application of jet impingement cooling on turbines blade leading edge. Gas turbines are extensively utilized in power generation and aerospace industries, where efficient cooling techniques are crucial to enhance the performance and lifespan of turbine blades. The leading edge of a turbine blade is particularly vulnerable to high-temperature exposure and thermal stresses, making it an essential area for effective cooling strategies. Jet impingement cooling is one of the most effective cooling techniques mostly used in the leading edge of rotating and stationary blades. This study aims to explore the performance of jet …

Design And Fem Modelling Of Mems Capacitive Accelerometer And Gyroscope For Quadcopter/Uav Applications, Shaikha Rashid Alnaqbi

Theses

This study presents the design, simulation, and analysis of Micro Electromechanical Systems (MEMS) sensors, constituting the principal components of MEMS-based Inertial Measurement Units (IMUs). The main objective of the study is to design, simulate and analyze 3-axis capacitive accelerometer and 3-axis gyroscope. The MEMS-based capacitive accelerometers and gyroscope are analyzed using Ansys Workbench. Modal, Static Structural and harmonic analysis are used to obtain resonant frequencies, deformation/stress and profile of amplitude over a wide range of frequencies. Mechanical sensitivity analysis of the designed accelerometer and gyroscope is performed using the Finite Element Method (FEM). Analytical Equations are developed to calculate mechanical …

Design And Application Of Circular Edge-Fed Linearly Polarized Patch Antenna With Enhanced Bandwidth And Gain For Respiratory Monitoring Systems, Mo’Ath Akram Al Hayek

Theses

This Master’s thesis explores the design and application of a circular edge-fed patch antenna for respiratory monitoring systems. The antenna, fabricated from a thin copper adhesive sheet, demonstrates compatibility with textile materials of low thickness and a relative permittivity of 1.3. Using CST Studio Suite 3D EM simulation software, the antenna’s design was optimized through extensive trials, achieving improved bandwidth and gain. Our findings indicate that the antenna successfully differentiates between various breathing patterns, including slow, normal, and fast breathing rates. The study’s managerial and research implications extend to healthcare, wearable technology sectors, and the broader scientific community. The research …

A Numerical Investigation Realizing The Flow Structure And Heat Transfer Performance Of The Potential Impinging Jets, Mohammed Sami Uddin Khan

Theses

The demand for improvement in the performance of gas turbines has led to the consideration of flows at increasingly high temperatures, but this introduces challenges in terms of maintaining their structural integrity and preventing overheating. To respond to these challenges, gas turbine manufacturers have turned to internal cooling, and jet impingement provides an effective solution for cooling the leading edge of the blades of gas turbines. In this study, the author numerically simulated the cooling performance of the leading edge of the blades of a gas turbine under constant heat flux by using five configurations of jet impingement: a steady …

Dual-Site Photoplethysmography Sensing For Noninvasive Continuous-Time Blood Pressure Monitoring Using Artificial Neural Network, Anas Mohmmad Rabab’Ah

Theses

Millions of people worldwide struggle from high blood pressure, often known as hypertension, and it is a major health concern that can lead to serious cardiovascular diseases, including heart attacks and many other consequences. Blood pressure monitoring that is reliable and accurate is crucial to the detection and management of hypertension. Although invasive techniques, such as arterial catheterization, are considered to be the most accurate means of evaluating blood pressure, they can be painful, time-consuming and carry a risk of complications.
This thesis presents the development of a real time non-invasive blood pressure monitoring system based on commercially available microcontroller …

Upgrading Biomass To Bio-Oil: Catalytic Hydrodeoxygenation And Pyrolysis Of Vanillin And Anisole Biomass Model Compounds, Ahmad J. Yaghi

Theses

The purpose of this project is to investigate capacity of selected formulations of catalysts toward the hydrodeoxygenation (HDO) of biomass model compounds in the gas phase with the underlying aim to produce hydrocarbon cuts that can be directly used as transportation fuels. The first part of this project is to devoted to illustrate procedures for the synthesis of potent (HDO) catalysts. Synthesized catalysts encompass nickel (Ni), cobalt (Co) and palladium (Pd) supported on zeolite, cerium oxide (CeO₂) or alumina (Al₂O₃). Various characterization techniques such as X-ray Diffraction (XRD), Temperature Programmed Reduction (TPR) were deployed …

Numerical Simulation Of Concrete Beams With Discontinuity Regions Reinforced With Nonmetallic Reinforcing Bars, Amena Mohammad Ousama

Theses

Nonmetallic Glass Fiber-Reinforced Polymer (GFRP) reinforcing bars are considered a viable alternative to the conventional steel reinforcement because of their high strength-to-weight ratio and noncorrosive nature. This research aimed to investigate the nonlinear structural behavior of GFRP-reinforced concrete beams with discontinuity regions (D-regions) through numerical analysis. Three-dimensional (3D) numerical models were developed to simulate the nonlinear structural behavior of GFRP-reinforced deep beams with and without web openings. The models adopted realistic constitutive laws that accounted for the nonlinear behavior of the materials used. Predictions of the numerical models were validated against published experimental data. A parametric study was conducted to …

Novel Investigation Of Catalytic Hydrogenation And Oxidation Of 1,3-Butadiene, Ali M. Alabedkhalil

Theses

The hydrogenation of 1,3 Butadiene (BD) is an important industrial process that is generally used to generate butene, which is a key feedstock to produce a variety of chemicals such as polymers, plastic, and synthetic rubber. This process involves reacting BD with hydrogen using different metallic Ni-based catalysts. In this study, Ni/Al₂O₃ and Ni/Nb₂O5 catalysts were used and investigated to perform the hydrogenation reaction because of their commercial availability, effective hydrogenation activity, and affordability compared to Platinum Group Metal (PGM) catalysts.

The catalytic reactions were conducted using a quartz tube reactor between a temperature range …

Thermohydraulic Performance Of 3d Printed Metal Heat Exchanger With Zig-Zag Minichannels, Aysha Rashed Alshamsi

Theses

This work proposes using zig-zag minichannels in heat exchangers for enhancing its performance while operating under balanced (heat capacity ratio of unity) and unbalanced flow (heat capacity ratio of 0.5) conditions for counter flow and parallel flow configurations. The performance of the heat exchangers is quantified in terms of effectiveness and pressure drops and studies are done for hot fluid Reynolds number ranging from 50 to 1500. This work employs a numerical study to investigate the performance of the heat exchanger with zig-zag minichannels.
Simulation is carried out using Fluent module of Ansys Workbench. The model used for simulation consists …

Electrochemical Investigation Of Copperzirconium Based Metallic Glass Cu₅₁Zr₃₀Hf₁₄Ag₅, Tamim Mohammad Ahmad

Theses

This thesis is concerned with the electrochemical investigation of the copper-zirconium

based metallic glass Cu₅₁Zr₃₀Hf₁₄Ag₅. Studying the corrosion behavior of the novel melt-spun metallic glass ribbons contributes to further research on the possibility of building future bio-implants. The objectives of this thesis are to synthesize the metallic glass ribbons which are free from cytotoxic elements using melt spinning technique, verify their amorphous nature using X-ray diffraction method, study the corrosion behavior using Potentiodynamic polarization and Electrochemical Impedance Spectroscopy in different acidic, neutral and basic solutions, and finally examine the surface morphology of …

Influencing Factors Of Ionic-Wind In A Spherical Structure Propulsion System For Silent Airplane, Tha’Er Khaled Ibrahem

Theses

Since the first airplane invented 100 years ago, most or all airplanes propulsion systems are based on moving parts powered by fossil-fuel which is impacting our environment by producing unwanted gases such as carbon dioxide, methane, greenhouse gases and more, furthermore, it is well known that there is a degradation in Oil & Gas resources on earth. Therefore, scientists are interested in finding an alternative way to fly an object. Recently, ionic wind-induced by Direct-Current (DC) Corona discharge have been introduced to enhance the future generation of airplanes without the need for moving objects. Corona discharge phenomena occurs when high …

A Parametric Numerical Analysis Investigation To Optimize The Performance Of The Ranque-Hilsch Vortex Tube, Muneer Ahmad Sungur

Theses

A vortex tube is a device that separates compressed air into two streams: one with a higher temperature (hot stream) and the other with a lower temperature (cold stream). It is a popular cooling option because it is small, safe, and affordable. The main objective of this thesis is to examine the energy separation performance of RHVT by varying the internal tapering angles of convergent angles (2°, 1.75°, 1.5°, 1.25°, 1°, 0.75°, and 0.5°), straight angles (0°), and divergent angles (0.5°, 1°, 2°, 4°, and 6°), While the cold mass fraction is constant (0.317). Length-to-diameter ratio (Lt/Dt), inlet pressure, and …

A Novel Approach For Detection Fault In The Aircraft Exterior Body Using Image Processing, Noura Nayef Almansoori

Theses

The primary objective of this thesis is to develop innovative techniques for the inspection and maintenance of aircraft structures. We aim to streamline the entire process by utilizing images to detect potential defects in the aircraft body and comparing them to properly functioning images of the aircraft. This enables us to determine whether a specific section of the aircraft is faulty or not. We achieve this by employing image processing to train a model capable of identifying faulty images. The image processing methodology we use involves the use of images of both defective and operational parts of the aircraft's exterior. …

Data-Driven Modeling Of Student Performance In The Time Of Distance Learning, Iman Saad Megdadi

Theses

One of the important aspects that all academic institutions work towards improving is Student Performance. It is obviously the primary indicator of success or failure of institutions. Student performance predictions are vital to instructors and educational decision makers to help, across all levels, tailor learning according to the students’ needs. Therefore, it is essential for Higher Education Institutions to predict student performance in distance learning which has been, and remains, the primary method of learning in some countries due to Corona Virus pandemic. For this reason, this research is going to predetermine a fitting definition of student performance in time …

Recycling Of Cured Carbon Fiber/Epoxy Resin Laminated Composites Scraps: Processing And Characterization, Khaled Mohammed Al Harmoodi

Theses

The concept of reinforced composites came decades ago from the need to fabricate high-strength, heat-resistant, wear-resistant, and low-density materials. The polymer matrix composites offer a wide range of applications due to the collaborative nature of the functional fillers and polymers present. Towards the twenty-first century, the aviation industry flourished due to flying being the preferred way of travel across states and countries. With such a massive demand for air transport, there is an equally parallel demand for the production of aircraft components. This study aims to reuse the waste of uncured composite prepreg scraps from the ply-cutting manufacturing process in …

Neural Network Based Reactive Control Of Point Absorber Wave Energy Converters, Abdelmoamen Ali Nasser

Theses

The main objective of this work is to develop a neural-network-based Reactive Control (RC) system for wave energy converters. The ability to maximize the power output of WEC while maintaining operation constraints, which can be physical or thermal, is crucial to the development of deployable control strategies. Having a control method that is robust, which means it handles uncertainty and noise very well, is one of the main performance criteria in evaluating the method. Therefore, this work starts by deriving an averaged WEC model to be simulated in MATLAB/Simulink. Additionally, the concepts of resistive loading control and reactive control (approximate …

Disturbance-Observer Based Control For Pwm Rectifiers Without Dc Voltage Oscillations Under Unbalanced Grid Conditions, Mohammed Samer Al-Razehi

Theses

A three-phase controlled rectifier is a power electronic converter that employs the grid voltages as an input to produce a constant dc voltage at its output through the use of a capacitor, known as dc-link capacitor. However, the switching devices of power converters can create harmonics in the grid current, which mandates the need for filters to ensure high-quality grid current. This explains why the power converter is normally connected to the grid using passive filters such as L filter or LCL filter. The L filter is normally preferred over LCL filter to reduce harmonic distortions in grid currents as …

Utilizing Date Pits In Microencapsulation: Effect Of Different Variations On Probiotic Survivability Under In Vitro Digestion, Asmaa Samir Al Hamayda

Theses

This work deals with the medicinal use of date pit powder, which turns it from a waste product to a useful stabilizer for the release of beneficial probiotics in the human intestine. The main objective of this work is to encapsulate probiotics with date pit beads and their subsequent release in the human intestine. The beads were formed using gravitational dripping technique, while INFOGEST protocol was used to test the digested beads and the release of viable probiotic cells. For the three date varieties Raziz, Naghal and Khadrawy, it was found that 0.1 g of date pit powder per 0.2 …

The Design Of A Point Of Care Fet Biosensor To Detect And Screen Covid-19, Nisreen Amer Mohammad Alnaji

Theses

This work proposes and demonstrates a biosensor with reduced Graphene Oxide (rGO) based Field Effect Transistor (FET) for rapid and selective detection of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). The main objective of this thesis is to detect the SARS-CoV-2 spike protein antigen on spot selectively and rapidly. The rGO channel is coated with the spike protein antibodies to achieve selectivity. Moreover, the biosensing performance and specificity are governed by decorating the sensor’s channel with Metal Nanoparticles (MNPs) such as, copper, and silver. The designed sensor successfully detects the SARS-CoV-2 spike protein and shows singular electrical behavior for detection. …

Sludge-Based Activated Carbon: Characterization And Performance For Removal Of Methylene Blue From Aqueous Solution, Ahmad Anwar Al Madhoon

Theses

Domestic wastewater treatment plants in the United Arab Emirates (UAE) produce 122 thousand tons of dried sludge annually. About 70% of this sludge is dumped in landfills, creating water and soil contamination. Sludge is an energy-rich organic material that could be converted into activated carbon by thermal or chemical processes. Potassium hydroxide has shown great potential as an activating agent for producing high-quality sludge based activated carbon (SBAC). However, its use adds to the cost of the production process. Thus, there is a need for an alternative activating agent that is not costly. One possible chemical is carbide lime which …

Biodegradable Heat Insulation Composites Based On Poly(Β-Hydroxybutyrate) And Date Palm Wood, Amal Ibrahim Mlhem

Theses

Residential buildings contribute the most to energy consumption. It was found that energy savings of 20% can be achieved through the thermal insulation of residential buildings in the United Arab Emirates. For this reason, research has been conducted in the field of sustainable thermal insulation materials. Wood-Plastic Composites (WPC) are a relatively new generation of biocomposites and are particularly suitable for construction and building applications, which offers high thermal and acoustic insulation properties., reducing carbon emissions and decreasing negative impacts on the environment due to their biodegradability, sustainability, renewability, and recyclability. The first part of this study investigated the thermal …

Quality-Of-Service Provisioning For Smart City Applications Using Software-Defined Networking, Basima Kurungadan

Theses

In the current world, most cities have WiFi Access Points (AP) in every nook and corner. Hence upraising these cities to the status of a smart city is a more easily achievable task than before. Internet-of-Things (IoT) connections primarily use WiFi standards to form the veins of a smart city. Unfortunately, this vast potential of WiFi technology in the genesis of smart cities is somehow compromised due to its failure in meeting unique Quality-of-Service (QoS) demands of smart city applications. Out of the following QoS factors; transmission link bandwidth, packet transmission delay, jitter, and packet loss rate, not all applications …

Static Testing Of Hybrid Rocket Engine Using Biomass Waste, Saleh Mohammed Musaed Badi

Theses

This work investigates experimentally for the first time the performance of two solid biomass wastes as propellants for a Hybrid Rocket Motor based on the combustion and propulsion parameters such as combustion chamber pressure, thrust force, chamber temperature, combustion characteristics, and flame length generated. The main objective of this study is to examine the performance of the proposed biomass fuels (Date stone powder and Jojoba waste powder) in comparison with typical hydrocarbon fuels. To make an accurate comparison, Paraffin Wax-based propellant was used in this study as a reference fuel to compare with biomass performance using the same testing facility …

Performance Evaluation Of Glass-Fiber Reinforced Cement-Free Geopolymer Concrete, Mohammad Zuaiter

Theses

The alkali-activation of aluminosilicate materials produces a geopolymer binder that promises to be a sustainable replacement to cement in concrete. Yet, such concrete has experienced brittle behavior and poor resistance to cracking. As a means of improving its performance, this research assesses the feasibility of utilizing glass fibers in slag-fly ash blended geopolymer concrete for structural applications. A blend of slag and fly ash served as the binding material. Two types of glass fibers were used individually or as a hybrid combination. Type A and B glass fibers had similar properties but different lengths of 24 and 43 mm, respectively. …

Using Metal-Organic Frameworks (Mof) To Reduce The Carbon Footprint Of Concrete, Mona Ibrahim El-Hallak

Theses

The production of concrete by the construction industry has a massive impact on the environment. The process of manufacturing its main component, cement, releases a considerable amount of anthropogenic carbon dioxide. This thesis is concerned with the production of sustainable and eco-friendly concrete that integrates metal-organic frameworks (MOF) to capture and offset the CO₂ emissions emitted during the production of cement. The main objective is to synthesize a MOF capable of capturing CO₂ in concrete through accelerated carbonation curing and to assess its impact on concrete performance. Different parameters were examined, including the MOF content, initial curing duration, …

Deep Learning Based Segmentation And Classification For Improved Breast Cancer Detection, Bita Khosrow Asadi Khosrow Asadi

Theses

Breast Cancer is a leading killer of women globally. It is a serious health concern caused by calcifications or abnormal tissue growth in the breast. Doing a screening and identifying the nature of the tumor as benign or malignant is important to facilitate early intervention, which drastically decreases the mortality rate. Usually, it uses ultrasound images, since they are easily accessible to most people and have no drawbacks as such, unlike in the other most famous screening technique of mammograms where in some cases you may not get a clear scan. In this thesis, the approach to this problem is …

Robust Detection Of Coronary Heart Disease Using Machine Learning Algorithms, Anas Haitham Domyati

Theses

Predicting whether or not someone will get heart or cardiac disease is now one of the most difficult jobs in the area of medicine. Heart disease is responsible for the deaths of about one person per minute in the contemporary age. Processing the vast amounts of data that are generated in the field of healthcare is an important application for data science. Because predicting cardiac disease is a difficult undertaking, there is a pressing need to automate the prediction process to minimize the dangers that are connected with it and provide the patient with timely warning. The chapter one in …

Effects Of Wettability, Lithology, And Permeability On The Optimum Slug Size Of Low Salinity Water Flooding In Carbonates: An Experimental Approach, Hala Khaled Hasan Alshadafan

Theses

Low salinity water flooding has attracted academic and industry communities due to its relatively simple and applicable technology. One of the drawbacks of applying the IOR/EOR technique is the lack of the availability of low salinity water in large quantities at the reasonable cost required for a technically and environmentally successful project. To overcome this problem, the industry proposed to use produced water/sea water after dilution, and reverse osmosis filter technology to achieve the required salinity. Both techniques are quite costly and might hinder the project's economic success. Low salinity water as slug size followed by high salinity water was …

Thermal Stress Mitigation Of Single-Phase Sinewave Inverter By Using Double Switch H Bridge Configuration, Mohammad Mousa Ahmad Hushki

Theses

The increasing demand for renewable energies and the ongoing advancement in the industry require continuously evolving power converters in terms of efficiency, power density, and reliability. Furthermore, power converters’ applications in harsh and remote environments such as offshore wind turbines demand robust and reliable designs to help reduce operational costs. Power switch failure is a critical reliability issue that leads to the converter going out of service, causing an unscheduled maintenance event. The main reason behind power switch failure is thermal cycling. Therefore, the first part of this thesis attempts to develop an effective double switch H bridge inverter topology …