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Evaluating The Trade-Offs Of Using Additive Manufacturing For Liquid Rocket Engines, Joshua Buettner Jan 2023

Evaluating The Trade-Offs Of Using Additive Manufacturing For Liquid Rocket Engines, Joshua Buettner

Theses

Liquid rocket engines (LRE) are among the most expensive components of any launch vehicle. While additive manufacturing (AM) shows promise in alleviating some of the costs of LREs, the use of AM could introduce new failure modes which would increase time spent in Test-Fail-Fix. This thesis demonstrates a methodology for understanding the trade-offs of using additive manufacturing for LREs to inform decision making. A decision matrix was used to choose the ideal AM process, and a quantitative model was applied to capture one of the trade-offs of using AM, that being increased surface roughness on LRE performance. A candidate component …


Solar Flare Forecasting : A Study Of Flare Coincidence, Christian W. Hall Jan 2023

Solar Flare Forecasting : A Study Of Flare Coincidence, Christian W. Hall

Theses

Data mining techniques that can support the forecasting of solar flares are explored. The main focus is to investigate the effects of flare coincidence on the evaluation of forecasts. Coincident flares are solar flares in a region of the Sun in which another flare has occurred recently, whereas other flares are denoted as non-coincident flares. Dimensionality reduction and classification are two of the types of techniques examined, where binary classification is used to issue yes/no forecasts of major solar flares. Five algorithms are considered as binary classifiers: k-nearest neighbors (k-NN), logistic regression (LR), support vector machines (SVM), random forest classifiers …


An Investigation Of Mission Designs To The Outer Solar System Supported By Centrifugal Nuclear Thermal Propulsion, William Ziehm Jan 2023

An Investigation Of Mission Designs To The Outer Solar System Supported By Centrifugal Nuclear Thermal Propulsion, William Ziehm

Theses

Centrifugal nuclear thermal propulsion (CNTP) has potential for supporting scientific missions to the outer solar system, shown by investigation of mission and vehicle architectures to the outer planets and Kuiper belt. The patched conic method provided initial guesses for numerical simulation and relationships between parameters of interest for trade studies, recommending engine performance parameters for missions supported by CNTP. Results of the patched conic model were validated by comparison to numerical results, which were within the expected variance for transit time with identical propellant margins based on literature. The trade studies gave a range of performance required to close rendezvous …


Extended, Exactly Solvable Chaotic Oscillator, Micah Tseng Jan 2023

Extended, Exactly Solvable Chaotic Oscillator, Micah Tseng

Theses

Although the study of chaotic systems is theoretically mature for abounding examples, few are readily applicable to engineering problems. One notable barrier is the lack of analytic solution to guide or validate an engineered intention. In this thesis, a small set of chaotic systems known for their analytic solutions is expanded. Specifically, a known solvable second order solvable chaotic oscillator with a simple matched filter is extended such that the data rate is decoupled from the natural oscillation frequency of the oscillator. This development allows for high frequency applications without the need for high frequency switching. An extended, exact analytic …


Analysis Of Interconnected Subreddits On The Reddit Social Network, Lance Lindner Jan 2023

Analysis Of Interconnected Subreddits On The Reddit Social Network, Lance Lindner

Theses

This thesis analyzes the Reddit social network to identify two aspects of interactions on that platform: (1) implicit leader-follower relationships, which are obtained by mining patterns of user interactions on the network and (2) highly “interconnected” subreddits which are obtained by scoring each subreddit using a “interconnectedness” value derived from the interaction patterns of users across subreddits. The data were obtained from Reddit in 2022 using a custom-built scrapper. This work analyzed 125,000 subreddits. The results show that the most highly connected subreddits on the Reddit network are ones that discuss content considered to be “not suitable for work” (NSFW). …


Computational Performance Assessment Of Buoyant Shrouded Turbines In Uae, Mohamed Farmaan Abdul Khader Jan 2023

Computational Performance Assessment Of Buoyant Shrouded Turbines In Uae, Mohamed Farmaan Abdul Khader

Theses

With the increase in the economic impact of fossil fuel consumption over the past few decades, the demand for alternative sources of fuel for consumer consumption led to the initiation of scientific research related to renewable resources. The present research aims at analyzing the wind energy capability at low and high altitudes in low wind regions like the UAE (United Arab Emirates) by studying the different wind speed-altitude models and studying the potential of augmenting wind turbines performance using diffuser augmented-floating turbine systems incorporating the horizontal axis wind turbine (HAWT). The study was conducted computationally using Ansys Fluent and MATLAB …


A Three-Dimensional Cfd Analysis For The Hydrodynamics Of The Direct Contact Heat Transfer In The Oxygen Production Slurry Bubble Column Reactor Of The Cu-Cl Cycle Of Hydrogen Production, Nibras Ibrahim Nassar Jan 2023

A Three-Dimensional Cfd Analysis For The Hydrodynamics Of The Direct Contact Heat Transfer In The Oxygen Production Slurry Bubble Column Reactor Of The Cu-Cl Cycle Of Hydrogen Production, Nibras Ibrahim Nassar

Theses

Hydrogen is becoming an increasingly attractive alternative fuel. As such it is important to investigate different methods of hydrogen production. This thesis examines the thermochemical process of splitting water using the three stage CuCl Cycle. In particular it examines the hydrodynamics of a direct heat contact, CuCl’s oxygen reactor for a two-phase system, using a three dimensional, Eulerian-Eulerian Computational Fluid Dynamics (CFD) model. The model was first verified using experimental results and compared to a two-dimensional CFD model by examining the gas holdup (αg) using a Helium-Water-Alumina system for different reactor heights (H) (45,55,65 cm), different superficial gas velocities (Ugs) …


Identifying The Causes Of Heart Disease Using Classification Techniques, Wadeema Alshamsi Jan 2023

Identifying The Causes Of Heart Disease Using Classification Techniques, Wadeema Alshamsi

Theses

Heart disease is a global epidemic that affects millions of people and is responsible for a significant portion of annual deaths worldwide. Timely diagnosis and prediction of heart disease can save countless lives, and advancements in information technology have opened up new avenues for improving medical diagnosis. In this project, we aimed to explore the use of machine learning classification techniques for predicting the presence of heart disease in patients. We deployed five classification techniques: Logistic Regression, Decision Tree, Random Forest, K Nearest Neighbors, and Support Vector Machine. We used a dataset of 1025 observations with 13 features and one …


Assessing The Health Effects Of Climate Change, Social Vulnerability, And Environmental Justice In Camden County, New Jersey, Daniil Ivanov Dec 2022

Assessing The Health Effects Of Climate Change, Social Vulnerability, And Environmental Justice In Camden County, New Jersey, Daniil Ivanov

Theses

Climate change negatively impacts health, while socially vulnerable and overburdened communities disproportionately experience climate change and negative health determinants. Camden County is used as a case study for analyzing environment, socioeconomics, and health. Environmental variables—PM2.5 and land cover of impervious surfaces, floodplains, and forests—were compared to the CDC Social Vulnerability Index (SVI) at the census tract level, finding significant correlations between land cover, air quality, and the SVI. The overburdened communities defined by the NJ Environmental Justice Law experienced a significantly higher incidence of emergency department visitation for respiratory, circulatory, and mental illnesses than non-overburdened communities. Health outcomes were compared …


A Neural Analysis-Synthesis Approach To Learning Procedural Audio Models, Danzel Serrano Dec 2022

A Neural Analysis-Synthesis Approach To Learning Procedural Audio Models, Danzel Serrano

Theses

The effective sound design of environmental sounds is crucial to demonstrating an immersive experience. Classical Procedural Audio (PA) models have been developed to give the sound designer a fast way to synthesize a specific class of environmental sounds in a physically accurate and computationally efficient manner. These models are controllable due to the choice of parameters from analyzing a class of sound. However, the resulting synthesis lacks the fidelity for the preferred immersive experience; thus, the sound designer would rather search through an extensive database for real recordings of a target sound class. This thesis proposes the Procedural audio Variational …


Enabling Autonomous Driving Using 5g And Beyond, Mahmoud Wadi Dec 2022

Enabling Autonomous Driving Using 5g And Beyond, Mahmoud Wadi

Theses

The number of road accidents reported last year in UAE was 3488 accidents resulted in the death of 381 people. The shift towards the need for an intelligent transport system (ITS) supported by the use of autonomous vehicles (AV) is needed. This paper discusses the evolution of autonomous driving supported with a 5G network mainly focusing on key enabler technologies such as enhanced mobile broadband (eMBB), massive machine type communication (mMTC), and ultra-reliable low latency communications (URLLC). Autonomous driving (AD) is involved in safety applications so the communication system has to be reliable while exchanging communication in real-time with low …


Machine-Learning Classifier To Detect Atrial Fibrillation Based On Facial Action Units, Chongyu Zhu Dec 2022

Machine-Learning Classifier To Detect Atrial Fibrillation Based On Facial Action Units, Chongyu Zhu

Theses

Facial action units (AUs) are numerical representations of indicative facial features drawn by facial landmark localization. Tiny muscular movements on the face can be reflected through facial AUs. In this project, using AUs to diagnose atrial fibrillation (AFib) in real-time is investigated for the first time, and AUs are shown to have a connection with AFib occurrence. Unlike ECG/PPG/VPG, the machine-learning-enabled AFib detector proposed in this project can realize real-time contactless monitoring of AFib continuously in home settings while maintaining the accuracy of AFib detection. ECG data and tablet image snapshots are synchronized to form the dataset that will be …


Timing Jitter From Broadband Radio Observations Of Millisecond Pulsars, Jackson Hebel Dec 2022

Timing Jitter From Broadband Radio Observations Of Millisecond Pulsars, Jackson Hebel

Theses

Timing the arrival of pulsar light is a critical tool for scrutinizing the characteristics of the interstellar medium (ISM) and the pulsar itself. Pulsar timing is affected by factors such as the solar system's kinematics, turbulence in the ISM, and intrinsic timing noise inherent to each pulsar. The North American Nanohertz Observatory for Gravitational Waves (NANOGrav) maintains a catalog of high-precision timing for millisecond pulsars. Using NANOGrav pulsars, and accounting for relative time-of-arrival (TOA) differences within observation epochs, the remaining noise in the TOA can be parsed out to just the jitter innate to the pulsar. This research utilizes wide …


Side-Channel Attacks And Countermeasures For The Mk-3 Authenticated Encryption Scheme, Peter Fabinski Dec 2022

Side-Channel Attacks And Countermeasures For The Mk-3 Authenticated Encryption Scheme, Peter Fabinski

Theses

In the field of cryptography, the focus is often placed on security in a mathematical or information-theoretic sense; for example, cipher security is typically evaluated by the difficulty of deducing the plaintext from the ciphertext without knowledge of the key. However, once these cryptographic schemes are implemented in electronic devices, another class of attack presents itself. Side-channel attacks take advantage of the side effects of performing a computation, such as power consumption or electromagnetic emissions, to extract information outside of normal means. In particular, these side-channels can reveal parts of the internal state of a computation. This is important because …


Initial Data Generation And Dynamical Simulations Of Binary Neutron Star Systems, Tanmayee Gupte Dec 2022

Initial Data Generation And Dynamical Simulations Of Binary Neutron Star Systems, Tanmayee Gupte

Theses

The recent detection of gravitational waves (GWs) from a system of binary neutron stars (BNS) in coincidence with electromagnetic observations has launched a new era of multimessenger astrophysics. In light of the complementary knowledge to be gained through simultaneous observations, BNS mergers are one of the main targets for terrestrial GW interferometric detectors. These observations may prove critical in understanding the equation of state (EOS) of the nuclear matter inside the neutron star core, which is still poorly constrained given current observations. Understanding the neutron star (NS) EOS is critical for binary parameter estimation, and will hopefully aid in the …


Assessing The Performing Arts Experience At A Stem-Based Institution, Benjamin Willmott Dec 2022

Assessing The Performing Arts Experience At A Stem-Based Institution, Benjamin Willmott

Theses

Past studies examined the role of performing arts within a STEM-based curriculum, but there has been little research to date on how to fully integrate the two into one unified program at the higher education level. A qualitative study was conducted utilizing a phenomenological approach vis-à-vis four focus groups with students engaged in the Performing Arts Scholarship Program at Rochester Institute of Technology in Rochester, NY. The commitment-trust theory of relationship marketing as well as self-efficacy theory were considered to ground the theoretical framework surrounding the success of the program and the experiences of a sample of 951 Performing Arts …


En’S Adventure: Exploring Modern Design Mechanics In Retro Adventure Games, Frank Fasola Dec 2022

En’S Adventure: Exploring Modern Design Mechanics In Retro Adventure Games, Frank Fasola

Theses

This project focuses creating a small game prototype that can be used to build a full game around. The primary focus is to create a short experience to establish the mechanics and gameplay of the game. Games made in the style of retro games are released every year, but most of these games strive to provide the same experience from the late 1980s. The project is a top down 2D retro adventure game made using modern techniques and learning from game development in the 30 years since these games were released.


Address Obfuscation To Protect Against Hardware Trojans In Network-On-Chips, Thomas Mountford Dec 2022

Address Obfuscation To Protect Against Hardware Trojans In Network-On-Chips, Thomas Mountford

Theses

Interconnection networks for multi/many-core processors or server systems are the backbone of the system as they enable data communication among the processing cores, caches, memory, and other peripherals. Given the criticality of the interconnects, the system can be severely subverted if the interconnection is compromised. The threat of Hardware Trojans (HTs) penetrating complex hardware systems such as multi/many-core processors are increasing due to the increasing presence of third-party players in a System-on-chip (SoC) design. Even by deploying native HTs, an adversary can exploit the Network-on-Chip (NoC) backbone of the processor and get access to communication patterns in the system. This …


Identifying Prospective Clients For Long-Term Bank Deposit, Mohamed Al Hammadi Dec 2022

Identifying Prospective Clients For Long-Term Bank Deposit, Mohamed Al Hammadi

Theses

The numerous characteristics of customers are often kept in bank databases, which are utilized to understand who they are. But it has been found in recent years that utilizing different Data Mining and Feature Selection (PCA) methods, customer traits and other factors connected to bank services have a big influence on consumers' decisions. Business analytics is an approach to conducting business that uses transactional data from an organization to acquire knowledge of how business operations can be enhanced by employing data mining methods to determine existing patterns that a firm can incorporate to generate significant data-driven choices to choose significant …


Predicting Failure Rate Of Oil & Gas Equipment Using Ml, Shaima Alblooshi Dec 2022

Predicting Failure Rate Of Oil & Gas Equipment Using Ml, Shaima Alblooshi

Theses

Value of time has become an important perspective in business application ranging from day to day working to big businesses. The value of time is more important in the case of refinery business which has become of paramount importance with increasing energy needs. The main point of contention in refinery operations is the periodic maintenance of the pipelines which consumes of valuable time and resources. With a proper solution which can cater the time requirements of the lead time. The fact is that time consumption is extremely critical for the operations of refinery. Therefore, the application of machine learning is …


Protectbot: A Chatbot To Protect Children On Gaming Platforms, Anum Faraz Dec 2022

Protectbot: A Chatbot To Protect Children On Gaming Platforms, Anum Faraz

Theses

Online gaming no longer has limited access, as it has become available to a high percentage of children in recent years. Consequently, children are exposed to multifaceted threats, such as cyberbullying, grooming, and sexting. The online gaming industry is taking concerted measures to create a safe environment for children to play and interact with, such efforts remain inadequate and fragmented. Different approaches utilizing machine learning (ML) techniques to detect child predatory behavior have been designed to provide potential detection and protection in this context. After analyzing the available AI tools and solutions it was observed that the available solutions are …


Progressing Suas-Based Remote Sensing Data Collection Automation: Performance Analysis Of The At-Altitude Radiance Ratio Method For Reflectance Conversion Of Multispectral And Hyperspectral Remote Sensing Data, Luke J.R. Decoffe Nov 2022

Progressing Suas-Based Remote Sensing Data Collection Automation: Performance Analysis Of The At-Altitude Radiance Ratio Method For Reflectance Conversion Of Multispectral And Hyperspectral Remote Sensing Data, Luke J.R. Decoffe

Theses

In remote sensing, the conversion of at-sensor radiance to surface reflectance for each pixel in a scene, canonically known as reflectance conversion, is an essential component of many diagnostic analysis tasks. This process is crucial to the production of accurate information for a variety of applications, notably precision agriculture. The empirical line method (ELM) is the most used technique among remote sensing practitioners due to its reliability and production of accurate reflectance measurements. However, the at-altitude radiance ratio (AARR), a more recently researched method, is attractive as it allows reflectance conversion to be carried out in real time throughout data …


Measuring Entanglement Using Programmable Holograms, Jason Ziskind Nov 2022

Measuring Entanglement Using Programmable Holograms, Jason Ziskind

Theses

The Einstein–Podolsky–Rosen (EPR) paradox proposes an entangled quantum state in high dimensional non-commuting observables, position and momentum. We experimentally demonstrate a novel method for measuring spatial correlations in joint position and joint momentum space for entangled photons in an EPR-like state. Research in the field of quantum optics can provide insight into quantum information processing, communication, quantum key distribution, and further investigation into the EPR paradox and locality. Unlike existing techniques, we take measurements of non-commuting observables using a static configuration. A 405nm pump laser incident on a Bismuth Borate nonlinear crystal produces an EPR state as a pair of …


A Taguchi-Grey Relational Analysis Of Fdm Printed Pla, Essa Hareb Almehairi Nov 2022

A Taguchi-Grey Relational Analysis Of Fdm Printed Pla, Essa Hareb Almehairi

Theses

Additive manufacturing (AM) is an environmentally friendly process of constructing 3D objects by using Computer Aided Design (CAD) models. The material can be metals in powder form, thermoplastics, thermosets, ceramics, and more. AM is divided into seven main categories according to the American Society for Testing and Manufacturing (ASTM), and one of the most common types is material extrusion. In material extrusion, solid materials, most commonly thermoplastics, are preheated and extruded out of a nozzle from which the material is deposited layer by layer. Material extrusion is widely considered as one of the most user friendly and inexpensive 3D printers. …


A Taguchi-Grey Relational Analysis Of Fdm Printed Pla, Essa Hareb Almehairi Nov 2022

A Taguchi-Grey Relational Analysis Of Fdm Printed Pla, Essa Hareb Almehairi

Theses

Additive manufacturing (AM) is an environmentally friendly process of constructing 3D objects by using Computer Aided Design (CAD) models. The material can be metals in powder form, thermoplastics, thermosets, ceramics, and more. AM is divided into seven main categories according to the American Society for Testing and Manufacturing (ASTM), and one of the most common types is material extrusion. In material extrusion, solid materials, most commonly thermoplastics, are preheated and extruded out of a nozzle from which the material is deposited layer by layer. Material extrusion is widely considered as one of the most user friendly and inexpensive 3D printers. …


Are Numerical Symbols Fundamental To Neural Computation?, Mirinda James Nov 2022

Are Numerical Symbols Fundamental To Neural Computation?, Mirinda James

Theses

Abstract: Neuroclassicism is the view that cognition is computation and that core mental processes, such as perception, memory, and reasoning are products of digital computations realized in neural tissue. Cognitive psychologist C. R. Gallistel uses this classical framework to argue that all cognitive information processing is based on symbolic operations performed over quantitative values (i.e. numbers) stored in the brain, much like a digital computer. Assuming this hypothesis, he investigates how the brain stores quantitative information (i.e. the numerical symbols involved in neural computation). He claims that it is more plausible that memories for numbers are stored within molecular mechanisms …


Taxonomic Revision And Morphometric Analysis Of Selected Anthurium (Araceae) Species From Bolivia And Peru, Daniel M. Tarazona Ocana Nov 2022

Taxonomic Revision And Morphometric Analysis Of Selected Anthurium (Araceae) Species From Bolivia And Peru, Daniel M. Tarazona Ocana

Theses

The genus Anthurium (Araceae) consists of around 1,200 species distributed in the Neotropics, particularly in Central and South America. The montane forests in the eastern flank of the Andes, ranging from northern Ecuador to central Bolivia; hereafter, the East Andes Gradient region, are particularly rich in terms of species diversity, and include an understudied group of Anthurium species endemic to the region. Within this group of species, some taxa are difficult to distinguish from each other mainly due to the lack of identification keys, incomplete species descriptions and unknown synonyms. In this study, a combination of traditional taxonomic techniques and …


Investigating Teachers’ And Lead Teachers' Perspectives On The Impact Of Stream On Enhancing Teaching, Learning And Professionalism In The Emirates Schools Establishment, Hosam Rashad Badawy Nov 2022

Investigating Teachers’ And Lead Teachers' Perspectives On The Impact Of Stream On Enhancing Teaching, Learning And Professionalism In The Emirates Schools Establishment, Hosam Rashad Badawy

Theses

STREAM education is the latest development of STEM and STEAM educational approaches in the United Arab Emirates schools. It is gaining traction because of the global market's massive economic and technological advancement, as STREAM employment is in growing demand. Educational policymakers and leaders in the UAE advocate for the development and implementation of STREAM to enhance innovation and entrepreneurship skills, leading to a drastic shift in teaching, learning and professionalism. According to the study, the STREAM approach enhances teachers' professionalism, students' creative skills and the learning of 21st century survival skills such as communication, collaboration, creativity, critical thinking, digital …


Modified Titani Derived From Ti – Oxo Clusters: Synthesis, Structure, And Photocatalytic Activity, Fatmah Rashed Ali Alkindi Nov 2022

Modified Titani Derived From Ti – Oxo Clusters: Synthesis, Structure, And Photocatalytic Activity, Fatmah Rashed Ali Alkindi

Theses

Titanium dioxide (TiO2), an important semiconductor, has been used in various applications ranging from sunblock additives to self-cleaning window coatings, antibacterial agents, photovoltaics, and photocatalysis. Due to its photostability, TiO2 is an extensively used semiconductor photocatalyst in many industries. This thesis represents the synthesis, structure, and photocatalytic activity of TiO2 (Anatase) photocatalyst, which was prepared using hexanuclear titanium-oxo cluster precursor via temperature-controlled calcination. The optical property of the prepared photocatalyst was investigated using UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), powder X-ray diffraction (PXRD) for phase determination, scanning electron microscopy (SEM) for morphology and structural analysis, Brunauer−Emmett−Teller …


Neural Network Based Reactive Control Of Point Absorber Wave Energy Converters, Abdelmoamen Ali Nasser Nov 2022

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 …