Engineering Commons^™

Nonlinear Attitude Control For A 6u Cubesat With A Flexible, Deployable Boom, Jared Walker

Theses and Dissertations

A satellite attitude control system was developed in MathWork’s Simulink for a 6U CubeSat with a flexible appendage payload. The flexible appendage is a boom that is able to store into a compact size and deploy out to 1 meter. The boom deploys a sensor attached to the end of the boom. The boom/sensor payload was modeled as a spring-mass-damper system. The equivalent spring constant of the payload was determined by the the natural frequency of the system. A modal analysis in ANSYS Mechanical was used to determine the natural frequencies and mode shapes of the payload. The attitude control …

Living Docks: Structural Implications And Determination Of Force Coefficients Of Oyster Mats On Dock Pilings In The Indian River Lagoon, Ryan Christiansen

Theses and Dissertations

Brevard County, Florida, is facing rapid population growth and increased pollution entering the Indian River Lagoon (IRL), impairing water quality and damaging the ecosystem. This is problematic not only for public health and environmental stability, but also for the economy. The Living Docks initiative was created to combat environmental degrade in the lagoon and restore natural functions back to the ecosystem. With increased urbanization along coastal systems, there is opportunity for new forms of ecological engineering such as Living Docks, which attaches oyster mats to dock pilings as a means to promote the growth of filter feeding organisms. It is …

Pilot’S Willingness To Operate In Unmanned Aircraft System Integrated Airspace, Lakshmi Vempati

Doctoral Dissertations and Master's Theses

The interest in Unmanned Aircraft Systems (UAS) use for private, civil, and commercial purposes such as package delivery, inspection, surveillance, and passenger and cargo transport has gained considerable momentum. As UAS infiltrate the National Airspace System (NAS), there is a need to not only develop viable, safe, and secure solutions for the co-existence of manned and unmanned aircraft, but also determine public acceptance and pilot’s willingness to operate an aircraft in such an integrated environment. Currently there is little or no research on pilot’s perceptions on their willingness to operate an aircraft in UAS integrated airspace and airports.

The purpose …

Active Drag Reduction Of Ground Vehicles Using Air-Jet Wheel Deflectors, Kaloki Nabutola

Doctoral Dissertations and Master's Theses

Seven turbulence models were used to simulate the flow within the wheelhouse of a simplified vehicle body. The performance of each model was evaluated by comparing the aerodynamic coefficients obtained using computational fluid dynamics (CFD) to data collected from wind tunnel experiments. The performance of large eddy simulation (LES) and detached eddy simulation (DES) was largely dependent on the time step and grid size to accurately resolve turbulent eddies. The standard k-e, realizable k-e, k-w, DES, and LES all trended towards a drag coefficient which was 20% lower than the experimental value. In all numerical cases, the lift coefficient was …

Analysis Of Local Convection Heat Transfer Rates Of Supercritical Carbon Dioxide In Tubes, Yang Chao

Doctoral Dissertations and Master's Theses

Numerical investigation on thermodynamic characteristics of pure supercritical carbon dioxide (𝑆𝐶𝑂2) and mixtures of Helium and 𝑆𝐶𝑂2 in horizontal straight tubes with diameter of 6mm under cooling and heating conditions is carried out by using SST 𝑘 − 𝜔 turbulence model. The computations are conducted at operating pressure of 8MPa with various operating conditions. Simulations are conducted by using the latest poly-hexcore mesh method in ANSYS FLUENT 19.2 and tetrahedral mesh method in CFX 19.2, results and solving time are compared. The effect of heat flux, mass flux, inlet temperature and buoyancy on heat transfer performance are studied, pressure drop …

Unsteady Internal Ballistics Of A Hybrid Rocket, Naveen Sri Uddanti

Doctoral Dissertations and Master's Theses

With the recent progress made in the field of space tourism, hybrid rocket engines have gained a renewed interest due to their simplicity, low cost, operational flexibility, and safety. The flow in the ports of a hybrid rocket motor involves several coupled unsteady phenomena like moving walls, combustion in a boundary layer flow and mass addition along the port, through the regression of the solid fuel wall. The flow in the combustion chamber of a hybrid rocket is inherently unsteady because the geometry of the port varies as a function of space and time. In the current research, we develop …

Determinants Of Aviation Students’ Intentions To Use Virtual Reality For Flight Training, Stephanie Gill Fussell

Doctoral Dissertations and Master's Theses

Immersive simulation technology has been incorporated into numerous training environments, including medicine, engineering, and marketing. The aviation industry, in particular, has a history of embracing technology to enhance training and has especially regulated the requirements of devices for flight training. Virtual reality (VR) is the newest technology being adapted for training purposes. Many educational institutions training providers are incorporating virtual environments (VE) and VR systems into curricula and training programs to expand educational opportunities, enhance learning, promote deep cognitive learning, and leverage the abilities of a generation of students who have adopted technology from an early age.

As VR is …

Safety Systems, Culture, And Passengers’ Willingness To Fly In Autonomous Air Taxis, Kenneth Alexander Ward

Doctoral Dissertations and Master's Theses

As city populations grow, the transportation industry plans to alleviate traffic congestion by introducing the urban air mobility (UAM) concept, in which small passenger and cargo aircraft augment metropolitan transportation networks. A key component of UAM is that of air taxis, which are on-demand air services for individuals and small groups. In addition, UAM companies are designing the aircraft to operate fully autonomously: The intent is for the vehicles to arrive and transport people from point to point without input from human pilots.

In studies of passengers’ perceptions, researchers found that safety was among the top passenger concerns. The international …

Using Online Discussions To Connect Theory And Practice In Core Engineering Undergraduate Courses, Lisa B. Bosman, Somesh Roy, Walter M. Mcdonald, Cristinel Ababei

Electrical and Computer Engineering Faculty Research and Publications

Providing engineering undergraduate students opportunities to connect real-world applications with theory is key to preparing them for the workforce; however, this task often requires a balancing act between meeting course objectives in content-heavy core engineering undergraduate courses and providing experiences that connect real-world applications with theory. This study seeks to address this problem through the integration of online discussion prompts to promote a connection to real-world practical applications. The study included undergraduate students enrolled in three engineering core courses. The hypothesis was that participation in online discussions (using prompts) would lead to 1) an increase in student empowerment towards self-regulated …

Investigation On The Morphology Of Charge-Transfer Complexes In Low Density Polyethylene, Wade Korf

Master's Theses

Fillers are used ubiquitously throughout the fields of polymer and material science to overcome many inherent limitations to polymeric materials (i.e. poor stiffness or strength) and to expand their potential applications. There is a need to develop controllable particle architectures to better understand fundamental structure-property relationships in particle reinforced polymer composites. Charge-transfer complexes (CTCs) can assemble in situ into various needle and dendritic shapes via simple fabrication processes and at low loading levels. In this study, the effect of tetrathiafulvalene (TTF) and 7,7,8,8-tetracyanoquinodimethane (TCNQ) CTC crystallites of various shapes and sizes on composite mechanical properties was investigated in an LDPE …

Bio-Inspired Wings In High Freestream Turbulence: A Numerical And Experimental Study, Alexia Martinez Ibarra

Theses and Dissertations

The aerodynamics and flow field characteristics of a NACA 0010 airfoil with leading-edge modifications were investigated in flow with freestream turbulence intensity of 4%. A set of 4 airfoils, each of them with different wavelength (4, 8, 10, 12 tubercles along the spanwise direction) was experimentally studied. An unmodified NACA 0010 airfoil was used as baseline. The Reynolds number was varied from 201,200 to 351,600. The angle of attack was varied within the range of -6 to 20 degrees. Several techniques were used to investigate the characteristics of the airfoils such as wake profile surveys, 6-axis force measurements, and Particle …

Carbonaceous Nanomaterial: Rapid Synthesis, Property Characterization And Theoretical Analysis, Varun Gupta

Theses and Dissertations

In this thesis, An environmentally friendly and rapid synthesis of highly porous carbon nanomaterial is presented. The direct pyrolysis of the cane sugar was achieved in a hand-fabricated Teflon microchamber. Homogeneous heating and quick pyrolysis were carried out in 3 minutes using a household microwave oven. The porosity and surface area enhancement is obtained by in-step decompositions of household baking soda (sodium bicarbonate), a common household chemical. Sodium bicarbonate was specifically used to impregnate porous carbon foam with sodium oxide nanocomplexes, which were later washed to improve surface area and reduce oxygen content, making it suitable for applications such as …

Residual Service Life Prognostic Models For Tapered Roller Bearings, Jennifer Danni Lima

Theses and Dissertations

There are a few different bearing health monitoring technologies currently used in the railroad industry, both reactive and preventative detection systems. Reactive models have proven to be ineffective in monitoring bearing health, which has resulted in either unnecessary train stoppages and delays or in-service failures and bearing burn-off leading to catastrophic train derailments. Wayside preventative detection systems, while more effective than reactive technologies, are scarce and neglect railcars’ that do not travel over a specific route. This knowledge prompted the University Transportation Center for Railway Safety at UTRGV to develop an onboard bearing health monitoring system that can accurately assess …

Green Synthesis Of Reduced Graphene Oxide For Efficient Adsorption-Photocatalysis Studies In Methylene Blue Dye Degradation, Ling Er Valerie Siong

Student Works (2020-2029)

Dyes are one of the major components of industrial effluents. Owing to the complex structures of these toxic organic compounds, the removal of dyes from effluents possesses a great challenge in wastewater treatment. In order to tackle this issue, one of the effective methods is to remove dyes via the combination of adsorption and photocatalysis processes. In the present work, reduced graphene oxide (rGO) was fabricated from graphene oxide (GO) by using an environmentally friendly solvothermal approach, whereby ethanol was employed as a non-toxic reductant. In order to investigate the formation of rGO, the reduction of GO was carried out …

Wideband And Flat-Gain Optical Amplifier With Hafnia-Bismuth Erbium Co-Doped Fiber, Abduljabbar Al-Azzawi Alabbas Ahmed

Student Works (2020-2029)

A compact optical amplifier with a flat-gain characteristic is demonstrated using hafnia bismuth-erbium co-doped fiber (HB-EDF) as the gain medium. The HB-EDF was recently fabricated using a modified chemical vapor deposition (MCVD) process in conjunction with solution doping (SD) technique. The fiber has an Erbium ions concentration of 12500 wt. ppm, which was realized due to the co-doping with Hafnium and Aluminum ions. Firstly, the proposed amplifier was investigated for both single and double-pass configurations. It is found that the 0.5m long HB-EDF is the optimum length for the C-band region. For double-pass HB-EDFA, at input signal power of -10 …

Artifact Identification For Blood Pressure And Photoplethysmography Signals In An Unsupervised Environment, Pooi Khoon Lim

Student Works (2020-2029)

Physiological signals play a significant role in clinical diagnosis, it always acts as a major input of a decision support system. However, the physiological signal is easily corrupted by different factors especially motion artifacts. Several research works have been tried to recover the underlying physiological signal by suppressing the artifact. However, not much attention has been paid to situation where the artifact is too extreme and the artifact suppression is not possible. In this situation, physiological signal quality must be evaluated before any further assessment. In this study, an automated artifact detection algorithm was developed for Blood Pressure and PPG …

Classification Of Labour Pain Using Electroencephalogram Signal Based On Wavelet Method, Chong Yeh Sai

Student Works (2020-2029)

Electroencephalogram (EEG) is the recording of electrical activity of the cerebral cortex through electrodes placed on the scalp. EEG is used to acquire neurophysiological signals for application in clinical diagnosis and brain computer interface (BCI). However, in practical settings the EEG signals are often contaminated by signal artifacts known as the biological and environmental artifacts. These artifacts degrade EEG signals, thereby obstructing clinical diagnosis or BCI applications by distorting the observed power spectrum. Procedures for automated removal of EEG artifacts are frequently sought after in pre-processing and filtering of the EEG signals. In recent years, a combination of independent component …

Effects Of Polytetrafluoroethylenemicro–Particles On Mechanical Andtribological Properties Of Glass Fiberreinforced Polyoxymethylene, Kunnan Singh Jasbir Singh

Student Works (2020-2029)

Reinforcing polyoxymethylene (POM) with glass fibers (GF) enhances its mechanical properties, but at the expense of tribological performance. Formation of a transfer film to facilitate tribo–contact is compromised due to the abrasiveness of GF. As a solid lubricant, for example, polytetrafluoroethylene (PTFE) significantly improves friction and wear resistance. The effects of chemically etched PTFE micro–particles on the fiber– matrix interface of POM/GF/PTFE composites have not been systematically characterized. This research investigated the effects of PTFE micro–particles on mechanical and tribological properties of POM/GF/PTFE composites. Since PTFE is immiscible with most polymers, the surface was etched using sodium naphthalene salt dissolved …

Relative Contribution Of Arms And Legs Through Repetitive Assisted Sit-To-Stand Motion In Individuals With Incomplete Spinal Cord Injury, Abd Aziz Musfirah

Student Works (2020-2029)

Sit-To-Stand (SitTS) exercise is one of important prerequisites to achieve some functional independence goals in everyday life especially for individuals undergoing rehabilitation In general, the execution of SitTS in spinal cord injury (SCI) patients involves motor function in both upper and lower extremities. The use of arm support in particular is a very significant element while executing SitTS movement for SCI population. In addition, application of functional electrical stimulation (FES) onto the quadriceps muscles is one of the prescribed management for incomplete SCI to improve muscle action for simple lower limb movements. However, the relative contribution of upper and lower …

Energy-Efficient Data Transmission With Clustering And Compressive Sensing In Wireless Sensor Networks, Alagirisamy Mukil

Student Works (2020-2029)

One of the most important application of wireless sensor network is environmental monitoring. The application involves lifetime of sensor nodes for longer duration associating its energy module. Wireless sensor nodes deployed in sensing field aggregate enormous amount of sensed data and transfer them to the sink. The inherent limitation of energy carried within the battery of sensor nodes fetches extreme difficulty to acquire adequate network lifetime, becoming a bottleneck in forwarding data to sink. Hence the motivation is to reduce the amount of data transfer and attain energy efficiency. This is achieved by clustering and compressive sensing techniques. First objective …

Visualization Of Musical Instruments Through Midi Interface, John Jaminet

Undergraduate Theses and Capstone Projects

We have created a Music Visualization system that controls an LED strip by parsing MIDI signals that are sent by a musical instrument. This is achieved through a program that parses the MIDI note signals into three-byte RGB signals which are then transferred over WIFI to four Arduino boards that control the LEDs. The system provides a musician the ability to add a dynamic light display that responds to the music in real-time. The system utilizes Windows Presentation Foundation because of its event handling and GUI capabilities. The board we are using is the Arduino MKR 1010 WIFI board as …

Machine Learning Modeling Of Horizontal Photovoltaics Using Weather And Location Data, Christil Pasion, Torrey J. Wagner, Clay Koschnick, Steven J. Schuldt, Jada B. Williams, Kevin Hallinan

Faculty Publications

Solar energy is a key renewable energy source; however, its intermittent nature and potential for use in distributed systems make power prediction an important aspect of grid integration. This research analyzed a variety of machine learning techniques to predict power output for horizontal solar panels using 14 months of data collected from 12 northern-hemisphere locations. We performed our data collection and analysis in the absence of irradiation data—an approach not commonly found in prior literature. Using latitude, month, hour, ambient temperature, pressure, humidity, wind speed, and cloud ceiling as independent variables, a distributed random forest regression algorithm modeled the combined …

Integration Of Machine Learning For Reactive Power Control For A Distribution Feeder Simulation With External Load, Ivonne D. Acosta Molina

Electrical and Computer Engineering ETDs

It has been 32 years since the Brundtland Report was published. That was the first time that the term Sustainable Development (SD) was coined. In this context, renewable sources of energy play an important role on not to deplete our natural resources in order to meet our need without compromising future generations. Smart Grids are on the pathway to achieve the SD goals. This Thesis focuses on the integration of renewables, specifically Solar PV panels and inverters and its interactions with the distribution grid. Since the power injection caused by the PV inverter can alter the voltage range, Reinforcement Learning …

Integrated Photonic Device, Brittney Kuhn

Student Scholar Symposium Abstracts and Posters

In computer mediated communication networks, information is typically encoded optically to transmit signals over long distances. At a network node, the optical signal is transformed into the electrical domain, processed electronically, and transformed back to an optical state to reach its destination. Transitioning between optical and electrical encoding of the signal is a potential security weak point, especially for quantum communication links. If information can remain in one state as it travels through the network, then security breaches can be detected and dealt with more easily. Furthermore, keeping the information in one state can reduce power consumption in the network. …

Coordinated Autonomy Of Unmanned Aerial Vehicles (Uavs), Paribartan Dhakal

Honors Theses

Unmanned Aerial Vehicles (UAVs) are being extensively used in diverse sectors of the society for various tasks ranging from videography to an extremely sensitive situation such as first responders helping during a disaster. It has been seen that if a fleet of UAVs is deployed, they can perform a task quicker and more efficiently than a single UAV. With an increase in the number of UAVs, a problem arises of handling them with proper control structures. It has been studied that the Behavior Trees (BT) can be a better control architecture to handle the autonomous vehicles, as BTs are more …

Selfsame Epoxide-Amine Microparticle Systems: Investigation Of Crosslink Density, John J. Peyrefitte

Honors Theses

Epoxide-amine matrix materials containing microparticles with the same chemical composition provide a model system to study interphase formation in highly crosslinked epoxide-amine matrix materials. The epoxide monomer was varied between three different monomer systems to study the model system’s relationship with crosslink density. The same amine monomer, cure procedure, and stoichiometric ratio of epoxide and amine groups were used to prepare each type of microparticle and matrix material. The differences in the epoxide monomer structure affected the crosslink density of the unmodified matrix material, which was concluded to influence the effect of microparticle presence on crosslink density. For the unmodified …

A Model For Simulation Of Convective Heat Assisted Single Point Incremental Forming Of Thermoplastics, Shubhamkar Kulkarni

All Dissertations

The overarching objective of this research is to develop a finite element model for simulation of the single point incremental forming (SPIF) process at different temperatures including convective heat assisted SPIF (CHASPIF). Single point incremental forming (SPIF) is a flexible manufacturing process with low tooling costs and times compared to thermoforming and die forming, for low production volumes. Convective heat assisted single point incremental forming (CHASPIF) is a variant of the SPIF process in which an external hot air source is used to heat the region surrounding the tool to improve formability, which can be assessed either in terms of …

Enhancing Cellular Communications For Uavs Via Intelligent Reflective Surface, Dong Ma, Ming Ding, Mahbub Hassan

Research Collection School Of Computing and Information Systems

Intelligent reflective surfaces (IRSs) capable of reconfiguring their electromagnetic absorption and reflection properties in real-time are offering unprecedented opportunities to enhance wireless communication experience in challenging environments. In this paper, we analyze the potential of IRS in enhancing cellular communications for UAVs, which currently suffers from poor signal strength due to the down-tilt of base station antennas optimized to serve ground users. We consider deployment of IRS on building walls, which can be remotely configured by cellular base stations to coherently direct the reflected radio waves towards specific UAVs in order to increase their received signal strengths. Using the recently …

Hierarchical Multiagent Reinforcement Learning For Maritime Traffic Management, Arambam James Singh, Akshat Kumar, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

Increasing global maritime traffic coupled with rapid digitization and automation in shipping mandate developing next generation maritime traffic management systems to mitigate congestion, increase safety of navigation, and avoid collisions in busy and geographically constrained ports (such as Singapore's). To achieve these objectives, we model the maritime traffic as a large multiagent system with individual vessels as agents, and VTS (Vessel Traffic Service) authority as a regulatory agent. We develop a hierarchical reinforcement learning approach where vessels first select a high level action based on the underlying traffic flow, and then select the low level action that determines their future …

Comprehensive Second-Order Adjoint Sensitivity Analysis Methodology (2nd-Asam) Applied To A Subcritical Experimental Reactor Physics Benchmark: V. Computation Of Mixed 2nd-Order Sensitivities Involving Isotopic Number Densities, Ruixian Fang, Dan Gabriel Cacuci

Faculty Publications

This work applies the Second-Order Adjoint Sensitivity Analysis Methodology (2nd-ASAM) to compute the mixed 2nd-order sensitivities of a polyethylene-reflected plutonium (PERP) benchmark's leakage response with respect to the benchmark's imprecisely known isotopic number densities and the other benchmark imprecisely known parameters, including: (i) the 6 × 180 mixed 2nd-order sensitivities involving the total microscopic cross sections; (ii) the 6 × 21,600 mixed 2nd-order sensitivities involving the scattering microscopic cross sections; (iii) the 6 × 60 mixed 2nd-order sensitivities involving the fission microscopic cross sections; and (iv) the 6 × 60 mixed 2nd-order sensitivities involving the average number of neutrons produced …