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Articles 1 - 30 of 54
Full-Text Articles in Engineering
Characterizing Climb And Propeller Performance For A Fixed Pitch, Single-Engine, Electric Aircraft, Austin Lawrence Andwan
Characterizing Climb And Propeller Performance For A Fixed Pitch, Single-Engine, Electric Aircraft, Austin Lawrence Andwan
Theses and Dissertations
Electric aircraft are on the horizon. Both industry and regulators have an abundance of flight tests ahead to ensure safe operation of these new aircraft. Conventional performance standards regaurding edurance, climb performance and cruise conditions are largely not applicable to assessing an electrically propulsed aircraft. While battery technologies are the current barrier for electric aircraft, there also hasn’t been much flight testing to reveal their unique performance trends. This experiment focus’s on characterizing some of these performance trends obtained through a level flight and climb test in the Pipistrel Velis Electro. The rate-of-climb did not exhibit a decrease when the …
Hydrothermal Preprocessing Of Waste Corn Stover Into Advanced Biorefinery Feedstock, Md Tahmid Islam
Hydrothermal Preprocessing Of Waste Corn Stover Into Advanced Biorefinery Feedstock, Md Tahmid Islam
Theses and Dissertations
Waste corn stover is one of the most abundant agronomic resources in U.S., however, those are either incinerated or unprocessed in the field to avoid high logistical cost, economic forfeiture, and environmental complications. Hydrothermal carbonization (HTC) is a promising thermochemical process that transforms wet biomass like waste corn stover into a solid fuel called hydrochar, process liquid, and process gas. The recycle of process liquid is warranted as the HTC process liquid contains organic acid that would increase the mass yield and fuel quality of the hydrochar by catalyzing the HTC reactions. HTC also promotes the fuel quality by densifying …
Analysis Of Proposed Active Radiation Shielding Design Concept For Spacecraft, Claire Mechmann
Analysis Of Proposed Active Radiation Shielding Design Concept For Spacecraft, Claire Mechmann
Theses and Dissertations
A need exists to protect the crew of interplanetary spacecraft from lethal doses of Galactic Cosmic Radiation (GCR) and Solar Energetic Particles (SEPs). As plans progress to send humans beyond lower Earth orbit (LEO) and outside of Earth’s protective magnetosphere, agencies involved in this endeavor find themselves confronted with the obstacle of shielding the crew from this harmful radiation. A proposed active shielding concept design has been suggested, utilizing charged dielectric capacitors to deflect incoming charged particles. This analysis will examine the feasibility of the proposed design and offer potential materials useful for application. The results should prove informative for …
Developmental Evaluation Of The B-1b Aircraft, Jonathon Malycke
Developmental Evaluation Of The B-1b Aircraft, Jonathon Malycke
Theses and Dissertations
The purpose of this test was to perform a Developmental Phase IIA evaluation of the B-1B Lancer for the land-based, long-range, all-weather ground attack mission. One two-hour ground evaluation, one simulator and one flight totaling 7.5 hours was conducted under daylight, visual meteorological conditions from Dyess Air Force Base (AFB) in Abilene, Texas (337th Test and Evaluation Squadron). All test objectives were completed except the low altitude flight evaluation, landing pattern operations, and AFCS operations due to weather, maintenance and time constraints. The test aircraft was representative of a production B-1B aircraft and included a Sniper Targeting Pod and a …
The Effect Of Zonation, Biofouling, And Corrosion Products On Cathodic Protection Design For Offshore Monopiles, Caglar Erdogan
The Effect Of Zonation, Biofouling, And Corrosion Products On Cathodic Protection Design For Offshore Monopiles, Caglar Erdogan
Theses and Dissertations
Cathodic protection (CP) is required to prevent corrosion of the submerged steel for offshore wind monopile foundations in the marine environment. The design of these systems depends on the environmental conditions, including temperature, salinity, pH, dissolved oxygen, depth, micro- and macro-organisms, and water flow rates. The standards utilized to design cathodic protection systems consider only some of these conditions. This research identified the gaps in knowledge for the design of corrosion prevention systems for offshore wind monopile foundations and investigated the changes in cathodic current densities due to macro-galvanic cells, fouling communities and corrosion products established on uncoated vertical steel …
Framework For The Utilization Of The Agile Methodology In Engineering Consulting Services, Cristian Daniel Nuñez
Framework For The Utilization Of The Agile Methodology In Engineering Consulting Services, Cristian Daniel Nuñez
Theses and Dissertations
The guidelines that form the Agile methodology framework are developed and adapted to the engineering consulting services industry. Four tools recommended by the literature are developed and adapted for the specific case of this industry. The implementation of the use of these tools is intended to help adopt the Agile methodology more effectively. A company that performs consulting services for airports is taken as a case study. This company did not officially implement the Agile methodology at the time this research has been done. The data is obtained through a survey designed to associate the company's activities with the guides …
Thermal Design And Energy Analysis Of A Greenhouse In Microgravity Conditions, Nivedha Karigiri Madhusudhan
Thermal Design And Energy Analysis Of A Greenhouse In Microgravity Conditions, Nivedha Karigiri Madhusudhan
Theses and Dissertations
The recent progress in commercial space flights and prospects for interplanetary space missions has attracted more attention towards developing sustainable built environments in microgravity conditions. An important factor in establishing a sustainable living condition for outer space applications is the ability to produce food. The thermal design considerations in a greenhouse have a major impact on the survival, water efficiency, quantity, and quality of plants produced. The extremely low environmental temperatures necessitate the use of heaters which do consume energy. Given the scarcity of energy access, it is important to achieve proper thermal conditions with the lowest possible energy requirements. …
Tympanostomy Tubes In Children: A Fem Study Of Adverse Effects, Manuel Nicolas Jaramillo Bucheli
Tympanostomy Tubes In Children: A Fem Study Of Adverse Effects, Manuel Nicolas Jaramillo Bucheli
Theses and Dissertations
Background: The current study investigates if tympanic (myringotomy) tubes affect hearing by comparing the harmonic displacement response to sound excitation within the hearing frequency range for healthy vs. surgically-treated pediatric tympanic membranes. The use of ear myringotomy tubes has proven an effective method for combating recurrent ear infections in infants and children. These tubes are placed in the tympanic membrane through an incision and connect the middle ear to the external ear, thereby allowing fluid drainage and middle-ear ventilation. While this treatment has been proven beneficial in alleviating urgent pus accumulation in the middle ear, recent research shows that it …
Modeling, Verification, And Simulation Of A Uav Swarm Consensus Protocol, Rohit Martin Menghani
Modeling, Verification, And Simulation Of A Uav Swarm Consensus Protocol, Rohit Martin Menghani
Theses and Dissertations
Unmanned Aerial Vehicles (UAVs), particularly electrically powered multi-rotors, are becoming increasingly popular in the entertainment, transportation, logistics, and military sectors. One of the main drawbacks presented by these vehicles at the time of writing is the limited range achieved as a consequence of the limits of battery technology. One common method used to overcome such limitations, is the use of multiple vehicles in cooperation to achieve a certain goal. This application of UAVs is called swarming, where multiple agents can coordinate their actions to fly in a certain formation, to access a certain challenging area, or to fly further. As …
Importance Of Light Activation For Plant Cryptochrome And Antibacterial Drug Delivery Strategies, Merfat Ahmed Hammad
Importance Of Light Activation For Plant Cryptochrome And Antibacterial Drug Delivery Strategies, Merfat Ahmed Hammad
Theses and Dissertations
The goal of this project is to investigate the benefits of applying light in different systems. In the first part, the magnetoreception process that occurs in the light activated cryptochrome of Arabidopsis Thaliana was investigated. In the second part, photo-carbon monoxide releasing molecules (photo-CORMs) were investigated for their antibacterial effect to develop biomedical strategies. Overall, this has been achieved in three different studies. The first study investigated if the forward lightdriven reaction is involved in the magnetoreception process or not in cryptochrome (CRY). To accomplish this, the plant seedlings were tested for 90 minutes as follows: 5 minutes in the …
Investigating The Role Of Cryptochrome Activity In Arabidopsis Plant And Blue Light Exposure In Saos-2 Cell-Mediated Mineralization, Maria Nijr Albaqami
Investigating The Role Of Cryptochrome Activity In Arabidopsis Plant And Blue Light Exposure In Saos-2 Cell-Mediated Mineralization, Maria Nijr Albaqami
Theses and Dissertations
Cryptochromes (CRYs) are flavoproteins that absorb blue light and are associated with the perception of electromagnetic stimuli in a variety of organisms including animals and plants. When exposed to blue light, CRYs undergo flavin redox cycles and form radical pairs intermediates that are assumed to be magnetically sensitive as predicted by the radical-pair hypothesis. However, it is unknown if CRYs fulfill the criteria to act as biological magnetosensors. In the first aim, Arabidopsis thaliana seedlings were exposed to blue light and a time-dependent weak magnetic field at radiofrequency (RF) of 7 MHz as a diagnostic tool to test the radical-pair …
Stress-Based Topology Optimization Of Pi Preform-Bonded Composite Laminate Structure, Iwan Broodryk
Stress-Based Topology Optimization Of Pi Preform-Bonded Composite Laminate Structure, Iwan Broodryk
Theses and Dissertations
The purpose of this work is to explore the stress-based topology optimization of structure that utilizes laminated composites and 3D woven Pi preform joints. Simple geometry, loading, and boundary conditions are considered. At a finite element level, an aggregate stress ratio is developed for Pi joint and acreage laminate elements. A basic descent method of moving asymptotes (BDMMA) algorithm is created to solve all optimization problems. Topology results for two different stress-based formulations and a compliance minimization problem are compared, followed by an in-depth analysis at a Pi joint and laminate level.
Accelerated Aging Of Adhesively Bonded Composite Joints For Use In Material Screening And Selection During Development: A Review And Case Study, Marie Danielle Flanigan
Accelerated Aging Of Adhesively Bonded Composite Joints For Use In Material Screening And Selection During Development: A Review And Case Study, Marie Danielle Flanigan
Theses and Dissertations
Adhesively bonded structures are used in many high-tech industries such as aerospace, automotive, and defense. The application of these joints using composite adherends has increased in recent years because of improved strength-to-weight ratio, design flexibility, and lower concern for corrosion. Quality acceptance of these structures largely depends on reliability and durability which includes influence of environmental service conditions on long-term behavior. Characterization of long-term behavior presents a difficult challenge to those involved in material selection and design due to the long service life of the joint compared to the development time available and complexity of the degradation mechanisms. Therefore, different …
Comparison Of Stability And Control Characteristics Of The Pipistrel Virus Sw And Pipistrel Velis Electro, Sean Gregory Gunther
Comparison Of Stability And Control Characteristics Of The Pipistrel Virus Sw And Pipistrel Velis Electro, Sean Gregory Gunther
Theses and Dissertations
This document finds the stability and control affects of electric powerplant conversion on a pre-existing internal combustion powered Pipistrel Virus SW through comparison with the Pipistrel Velis Electro. Testing included analysis of both static and dynamic stability on the longitudinal and lateral-directional axes of the airplane. Due to the light sport airplane being used in testing, some of the intedended tests were unable to be performed, however, conclusions were still capable of being made. The primary conclusion is that electric conversion of an airframe has no significant negative consequences, with the airplane still exhibiting positive stability on all three axes. …
Examining The Effects Of Payload Type And Framing On Weather-Related Decision-Making In A Simulated Urban Air Mobility (Uam) Environment, Maria Chaparro Osman
Examining The Effects Of Payload Type And Framing On Weather-Related Decision-Making In A Simulated Urban Air Mobility (Uam) Environment, Maria Chaparro Osman
Theses and Dissertations
The purpose of the current research study was two-fold. First, the study examined the effect of payload type on the riskiness of weather-related decision-making in a simulated urban air mobility (UAM) environment. Second, the current study examined whether framing information using prospect theory (Kahneman & Tversky, 1979) could influence the riskiness of weather-related decision-making in a simulated UAM environment. In the context of the current study, riskiness referred to the risk associated with the decision outcome, specifically whether participants selected a risk-averse decision outcome (return to the departure site) or risk-seeking decision outcome (continue to the destination site) based on …
Piper Pa-28-181 Archer Iii Tail #931ec Flight Test Stability, Control And Performance, Steven Allan Sutton
Piper Pa-28-181 Archer Iii Tail #931ec Flight Test Stability, Control And Performance, Steven Allan Sutton
Theses and Dissertations
The following flight test was conducted as part of the culmination requirement for the Master of Science, Flight Test Engineer degree program from Florida Institute of Technology. The flight was conducted to gather data and produce a flight test report on the data gathered. The flight test plan consisted of a series of both Stability and Handling test point as well as basic aircraft performance points. The testing was planned to be accomplished over a single flight, for reasons discussed later in this report. The flight departed on the morning of 26 September, 2022 out of Bob Sikes Airport, KCEW, …
Towards Orchestration In The Cloud-Fog Continuum, Xavier Jesus Merino Aguilera
Towards Orchestration In The Cloud-Fog Continuum, Xavier Jesus Merino Aguilera
Theses and Dissertations
The proliferation of the Internet-of-Things has raised demand for computing, storage, and network resources. The cloud model is ill-equipped to handle the volume and variety of data travelling to and from the cloud’s core as more data is generated and consumed at the network’s edge. Some applications necessitate low-latency connectivity and geographical awareness, highlighting the cloud’s centralization shortcomings. By localizing resources, minimizing bandwidth utilization, and lowering latency, the fog and edge layers are proposed to circumvent these limitations. At these layers, resource orchestration is crucial because poor resource management has an impact on service delivery. The aim of this study …
Deep Learning Approach To Speech Recognition: A Signal Extractor & Producer For Artificial General Intelligence, Ahmad Zuhair S. Hasanain
Deep Learning Approach To Speech Recognition: A Signal Extractor & Producer For Artificial General Intelligence, Ahmad Zuhair S. Hasanain
Theses and Dissertations
The efficient use of a communication bandwidth starts with the data source. The features of the speech signals can be extracted and reconstructed to lower the Internet traffic of the acoustic artificial agents and to increase the quality of the automatic speech recognition systems. The Speech Quefrency Transform (SQT) is hereby introduced in the work to enrich the communication space between the artificial agents and mankind. We describe the motivation, methodology, and deep learning approach in detail as we apply the SQT technology to several applications: sharp pitch track extraction, real-time speech communications, and emotion recognition. The results were excellent. …
A Voice And Facial Recognition System To Protect Students From Being Forgotten Inside School Buses In The Kingdom Of Saudi Arabia, Ibrahim Alferaih
A Voice And Facial Recognition System To Protect Students From Being Forgotten Inside School Buses In The Kingdom Of Saudi Arabia, Ibrahim Alferaih
Theses and Dissertations
In this research, we discuss the situation of students in the three to eight year old age group. Every day in the Kingdom of Saudi Arabia during school days, more than 1,000,000 students are transported throughout the country by more than 15,000 school buses. Everything is dependent on the human element. During school transportation around the world, many children are forgotten inside the school bus and with many of them eventually going missing or even dying. The bus driver is usually busy and tired due to the focus on the road, which may make him lose focus on those on …
Understanding The Reaction Kinetics Of Polyurethane Flexible Foam, Caitlin Alma Mckinnon
Understanding The Reaction Kinetics Of Polyurethane Flexible Foam, Caitlin Alma Mckinnon
Theses and Dissertations
Polyurethane flexible foam is used throughout daily life predominantly as cushions for chairs and mattresses. Currently new foams are made through extensive research and development via trial and error. There are many reactions interacting with each other during the polyurethane generation process. The numerous reactions create difficulty in modeling and predicting the physical attributes of a foam. This thesis explores the kinetics associated with each reaction to generate a simple model to understand the reaction kinetics with the addition of some additives. This thesis focused on creating the foams in a real-world environment, including allowing ambient water vapor to be …
Numerical Study Of The Effects Of Injector Geometry On The Performance Of Rotating Detonation Engines, Xavier Roy
Numerical Study Of The Effects Of Injector Geometry On The Performance Of Rotating Detonation Engines, Xavier Roy
Theses and Dissertations
A study of the impact of injector geometry on the performance of rotating detonation engines is performed. A numerical scheme is developed to represent the rotating detonation engine physics. In order to simulate the interaction between the chamber and the injectors, a multizone capability is implemented inside the numerical tool. The model is calibrated to represent a hydrogen-air detonation. The rotating detonation engine annular chamber is unwrapped and studied as a two-dimensional planar domain with a periodic boundary condition. Several numerical experiments are conducted. In particular, injection parameters are examined, such as the injector inflow to channel area ratio, injection …
Preserving Users’ Privacy In Iot Systems Through Network-Based Access Control, Ahmed Khalid A Alhazmi
Preserving Users’ Privacy In Iot Systems Through Network-Based Access Control, Ahmed Khalid A Alhazmi
Theses and Dissertations
Privacy issues have plagued the rapid proliferation of the Internet of Things (IoT) devices. Resource-constrained IoT devices often obscure transparency for end-users. A lack of transparency and control complicates user trust in IoT. Additionally, a growing history of misuse and abuse exists in IoT. Notably, a smart TV has periodically scanned and collected users’ private information without consent, while power companies have adjusted the temperature of smart thermostats during heat waves. Due to a hybrid of distributed ecosystems within IoT, users cannot easily implement traditional access control over their devices as data flows within different nodes for storage and processing. …
Evaluating Nas Delay Impacts From Orbital Launch Operations At Cape Canaveral And Optimizing Launch Windows, Tanner Jordin Furr
Evaluating Nas Delay Impacts From Orbital Launch Operations At Cape Canaveral And Optimizing Launch Windows, Tanner Jordin Furr
Theses and Dissertations
The purpose of this study was to determine if there was an impact of Part 121 arrival delays into Orlando International Airport (MCO) due to orbital space launch operations at Cape Canaveral. U.S. Government archival data spanning ten months and over 22,000 flights was accessed and categorized into three research questions by day of week, time of day, and whether or not an orbital space launch occurred during the established time frame. Inferential analysis using the one-way ANOVA (RQ1) and two-way ANOVA (RQ2 and RQ3) was conducted and found no significant differences in average Part 121 arrival delays into MCO …
Propellant Optimization For A Pulsed Solid Propellant Thruster System For Small Satellites, Timothy Aaron Blackman
Propellant Optimization For A Pulsed Solid Propellant Thruster System For Small Satellites, Timothy Aaron Blackman
Theses and Dissertations
CubeSats have historically been used mostly for education, technology demonstration, remote sensing, and amateur radio relay applications. Yet with increased maneuvering capability, they can become effective tools in on-orbit servicing and space debris removal. To make this a reality, CubeSats must be enabled to perform effective rendezvous and proximity operations with non-cooperative client objects, requiring a high-thrust propulsion system. As CubeSats are inherently constrained in their volume and mass, any propulsion system must feature a high specific impulse to minimize the propellant mass requirement. As CubeSats are commonly launched as secondary payload, the use of pressurized propellant tanks is typically …
Optimizing Left Ventricular Assist Device Hemodynamics Via Patient Specific Computational Analysis, Jasmine Josefina Martinez
Optimizing Left Ventricular Assist Device Hemodynamics Via Patient Specific Computational Analysis, Jasmine Josefina Martinez
Theses and Dissertations
The best treatment for patients with end stage heart failure is a heart transplant but given the scarcity of donor hearts, a promising alternative treatment has become left ventricular assist devices (LVAD). However, complications such as right heart failure, stroke, and adverse hemodynamic outcomes continue to occur. This thesis will cover investigations into continuous flow LVAD treatment optimization techniques to improve patient outcomes. Optimization techniques explored include an in-house developed optimization algorithm that is completed in three phases on a computational lumped parameter model that is representative of the cardiovascular system using an electrical circuit analogy. This three-phase optimization technique …
Changes In Drought Characteristics Under Future Climate Projections, Diogo Stalin De Alcantara Araujo
Changes In Drought Characteristics Under Future Climate Projections, Diogo Stalin De Alcantara Araujo
Theses and Dissertations
Accumulating evidence on the impact of climate change on droughts, highlight the necessity for developing effective adaptation and mitigation strategies. Global Drought Layers were developed for historic and future runs of nine global climate models (GCM) of the Coupled Model Intercomparison Model 6th phase (CMIP6). Relative changes of drought characteristics were estimated, and hotspots were identified, especially in South America, Africa, Europe, Western USA, and Australia. Further, changes in future drought risk and severity in Australia are quantified. Historic conditions (1981-2014) and projections for mid-century (2015-2050) and end-century (2051-2100) from four shared socioeconomic pathways (SSP1-2.6, SSP2-4.5, SSP3-7.0 and SSP5-8.5) are …
Development Of Simulation Framework For Impact Analysis Of Launch Delays On Lunar Base Station, Giulio Cristello
Development Of Simulation Framework For Impact Analysis Of Launch Delays On Lunar Base Station, Giulio Cristello
Theses and Dissertations
Humans have not ventured beyond Earth since the days of the Apollo missions. NASA astronauts were the first and last to set foot on the lunar surface, and it is again thanks to NASA that the initiative to go back to the Moon is moving forward. The Artemis missions will land men and women on the lunar surface with the purpose of establishing a long-term presence on the Moon. The current Artemis Plan includes the Artemis Base Camp, a lunar base stationed on the lunar South Pole. The maintenance of the base will require frequent missions to be performed in …
Complexity Analysis And Parallel Implementation Of The Well Optimized Linear Finder (Wolf) Atmospheric Turbulence Compensation (Atc) Algorithm On Gpu Technology With Comparative Analysis Of Traditional Phase Diverse Atc Methods, Yang Xin
Theses and Dissertations
A new high-speed, high-accuracy general transfer function estimation method for diversitybased problems, known as the Well Optimized Linear Finder Algorithm (WOLF Algorithm), has been developed [1]. Compared to the traditional phase diversity ATC methods, the WOLF Algorithm has less computational complexity and better approximation of the Optical Transfer Function (OTF) and consequently the entrance pupil phases. We compare the time complexity between the traditional Phase Diversity atmospheric turbulence compensation approach and the WOLF Algorithm. The results show that the WOLF Algorithm is dramatically faster than traditional phase diversity methods theoretically. We also implement the time complexity results of the WOLF …
Computational Speed Improvement Of The Well Optimized Linear Finder (Wolf) Transfer Function Estimation Methodology For Phase-Diverse Atmospheric Turbulence Compensation (Atc) Applications Using Pre-Calculated, Parallel Complex Exponential Phase Difference Chains, Erlin He
Theses and Dissertations
The Well-Optimized Linear Finder (WOLF) high-speed, phase-dominant, transfer function estimation method was developed by Professor William W. Arrasmith at Florida Institute of Technology. The novel, high-speed, transfer function estimation method is robust and can be applied to atmospheric turbulence compensation (ATC)/blind deconvolution optical imaging problems. The WOLF methodology uses a diversitybased approach with an adapted error metric to quickly remove effects of atmospheric turbulence and system noise effects present in an incoherent, optical imaging system. In this research, we improve performance of the WOLF algorithm by investigating the impact of applying parallel processing technology to pre-calculate an expanding set of …
Model-Based Operational Performance Evaluation Of Augmented Reality Applications In Supported Employment Training, Ruo Lun Pan
Model-Based Operational Performance Evaluation Of Augmented Reality Applications In Supported Employment Training, Ruo Lun Pan
Theses and Dissertations
Supported employment is a service provided by social enterprises to help persons with disabilities (PWD) to assimilate into their work environment and maintain their jobs for as long as possible. Social enterprises that provide such services are able to receive incentives from the government but they still rely on a limited funding. Augmented reality (AR) has been tested in various fields such as remote support and training employees, including PWDs. This thesis aims to evaluate the operational performance of augmented reality in supported employment using a model-based systems engineering approach paired with a simulation model. The simulation model evaluates three …