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Full-Text Articles in Engineering

Foreground Removal In A Multi-Camera System, Daniel T. Mortensen Dec 2019

Foreground Removal In A Multi-Camera System, Daniel T. Mortensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Traditionally, whiteboards have been used to brainstorm, teach, and convey ideas with others. However distributing whiteboard content remotely can be challenging. To solve this problem, A multi-camera system was developed which can be scaled to broadcast an arbitrarily large writing surface while removing objects not related to the whiteboard content. Related research has been performed previously to combine multiple images together, identify and remove unrelated objects, also referred to as foreground, in a single image and correct for warping differences in camera frames. However, this is the first time anyone has attempted to solve this problem using a multi-camera system. …


The Influences Of Calculus I On Engineering Student Persistence, Amie Baisley Dec 2019

The Influences Of Calculus I On Engineering Student Persistence, Amie Baisley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

About half of the students that are declared engineering majors end up leaving engineering within their first two years at the university. This happens following the required math and science courses that these students must take before getting into the technical engineering coursework. There are two systems that students must be a part of at the university to feel comfortable and have the desire to continue on in their degree. These include the academic system and the social system. The experiences engineering students have during their first required math course, Calculus I, is likely not promoting integration into these two …


Built-In Return-Oriented Programs In Embedded Systems And Deep Learning For Hardware Trojan Detection, Nathanael R. Weidler Dec 2019

Built-In Return-Oriented Programs In Embedded Systems And Deep Learning For Hardware Trojan Detection, Nathanael R. Weidler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Microcontrollers and integrated circuits in general have become ubiquitous in the world today. All aspects of our lives depend on them from driving to work, to calling our friends, to checking our bank account balance. People who would do harm to individuals, corporations and nation states are aware of this and for that reason they seek to find or create and exploit vulnerabilities in integrated circuits. This dissertation contains three papers dealing with these types of vulnerabilities. The first paper talks about a vulnerability that was found on a microcontroller, which is a type of integrated circuit. The final two …


Development And Testing Of A Hydrogen Peroxide Injected Thrust Augmenting Nozzle For A Hybrid Rocket, Mark C. Heiner Dec 2019

Development And Testing Of A Hydrogen Peroxide Injected Thrust Augmenting Nozzle For A Hybrid Rocket, Mark C. Heiner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During a rocket launch, the point at which the most thrust is needed is at lift-off where the rocket is the heaviest since it is full of propellant. Unfortunately, this is also the point at which rocket engines perform the most poorly due to the relatively high atmospheric pressure at sea level. The Thrust Augmenting Nozzle (TAN) investigated in this paper provides a solution to this dilemma. By injecting extra propellant into the nozzle but downstream of the throat, the internal nozzle pressure is raised and the thrust is increased, and the nozzle efficiency, or specific impulse is potentially improved …


Revolution In Autonomous Orbital Navigation (Raon), Rachit Bhatia Dec 2019

Revolution In Autonomous Orbital Navigation (Raon), Rachit Bhatia

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spacecraft navigation is a critical component of any space mission. Space navigation uses on-board sensors and other techniques to determine the spacecraft’s current position and velocity, with permissible accuracy. It also provides requisite information to navigate to a desired position, while following the desired trajectory. Developments in technology have resulted in new techniques of space navigation. However, inertial navigation systems have consistently been the bedrock for space navigation.

Recently, the successful space mission GOCE used on-board gravity gradiometer for mapping Earth’s gravitational field. This has motivated the development of new techniques like cold atom accelerometers, to create ultra-sensitive gravity gradiometers, …


Experimental Investigation Of N2o/O2 Mixtures As Volumetrically Efficient Oxidizers For Small Spacecraft Hybrid Propulsion Systems, Rob L. Stoddard Dec 2019

Experimental Investigation Of N2o/O2 Mixtures As Volumetrically Efficient Oxidizers For Small Spacecraft Hybrid Propulsion Systems, Rob L. Stoddard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A hybrid thruster system utilizes propellants in two different stages, traditionally a solid fuel and a gaseous or liquid oxidizer. Recently hybrid thrusters have become a popular topic of research due to the high demand of a ”green” replacement for hydrazine. Not only are hybrid thruster systems typically much safer than hydrazine, but they are also a low-cost system with a high reliability in performance. The Propulsion Research Laboratory (PRL) at Utah State University (USU) has developed a hybrid thruster system using 3-D printed acrylonitrile butadiene styrene (ABS) as the fuel and gaseous oxygen (GOX) as the oxidizer. This system …


Reservoir Applications Of Arced Labyrinth Weirs, Seth D. Thompson Dec 2019

Reservoir Applications Of Arced Labyrinth Weirs, Seth D. Thompson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In recent years, magnitudes of flood estimates used in hydraulic design have increased for many reservoirs. Consequently, many existing spillways are now deficient as they do not meet current discharge capacity requirements. To rehabilitate existing, fixed-width spillways, labyrinth weirs are often viable solutions. For reservoir applications, arcing labyrinth weirs into the reservoir increases hydraulic efficiency. This results from better cycle orientation to the approaching flow field.

This study supplements available arced labyrinth weir hydraulic data by observing flow characteristics of three laboratory-scale physical models and two numerical (CFD) models. Physical model results provide head (energy)-discharge data and empirical coefficients for …


Rapid Prediction Of Low-Boom And Aerodynamic Performance Of Supersonic Transport Aircraft Using Panel Methods, Ted N. Giblette Dec 2019

Rapid Prediction Of Low-Boom And Aerodynamic Performance Of Supersonic Transport Aircraft Using Panel Methods, Ted N. Giblette

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Utah State University Aerolab developed and tested a set of tools for rapid prediction of the loudness of a sonic boom generated by supersonic transport aircraft. This work supported a larger effort led by Texas A&M to investigate the use of adaptive aerostructures in lowering sonic boom loudness at off design conditions. Successful completion of this effort will improve the feasibility of supersonic commercial transport over land.

Funding was provided by a NASA University Leadership Initiative grant to several universities, including Utah State University, as well as industry partners to complete this work over a five year period. The …


Advancing Cyberinfrastructure For Collaborative Data Sharing And Modeling In Hydrology, Tian Gan Dec 2019

Advancing Cyberinfrastructure For Collaborative Data Sharing And Modeling In Hydrology, Tian Gan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Hydrologic research is increasingly data and computationally intensive, and often involves hydrologic model simulation and collaboration among researchers. With the development of cyberinfrastructure, researchers are able to improve the efficiency, impact, and effectiveness of their research by utilizing online data sharing and hydrologic modeling functionality. However, further efforts are still in need to improve the capability of cyberinfrastructure to serve the hydrologic science community. This dissertation first presents the evaluation of a physically based snowmelt model as an alternative to a temperature index model to improve operational water supply forecasts in the Colorado River Basin. Then it presents the design …


Gpu-Accelerated Demodulation For A Satellite Ground Station, Emily Clark Young Dec 2019

Gpu-Accelerated Demodulation For A Satellite Ground Station, Emily Clark Young

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

One consequence of the increasing number of small satellite missions is an increasing demand for high data rate downlinks. As the satellites transmit at high data rates, ground-side receivers need to demodulate the transmitted data as quickly as possible. While application specific hardware can be designed, software defined radio solutions for ground stations are attractive for their flexibility, adaptability, and portability.

Another industry trend is the increasing use of Graphics Processing Units (GPUs) in general-purpose processing. By performing many operations simultaneously, GPUs are capable of accelerating processing when given a problem that can be implemented in a parallel manner. Furthermore, …


Reducing Thermal Bridging And Understanding Second-Order Effects In Concrete Sandwich Wall Panels, Taylor J. Sorensen Dec 2019

Reducing Thermal Bridging And Understanding Second-Order Effects In Concrete Sandwich Wall Panels, Taylor J. Sorensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Structural engineers have traditionally detailed structures with structural and fabrication efficiency in mind, but often based on a limited understanding of thermal efficiency. Some connection designs can create significant thermal bridging, leading to unnecessary heat transfer and even premature degradation through condensation. Thermal bridging occurs when heat transfer is given a path through a more conductive material like concrete or steel rather than insulation. Concrete sandwich wall panels (SWP) tend to be highly efficient at preventing heat transfer in the middle of panels, with greatest heat transfer occurring at connections. This project identified thermally efficient details for future SWP construction …


Energy Management Of Dynamic Wireless Power Transfer Systems For Electric Vehicle Applications, Ahmed N. Azad Dec 2019

Energy Management Of Dynamic Wireless Power Transfer Systems For Electric Vehicle Applications, Ahmed N. Azad

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wireless power transfer is a method of transferring electric power from a transmitter to a receiver without requiring any physical connection between the two. Dynamic Wireless Power Transfer (DWPT) entails having the transmitters buried under the roadway and the receiver unit being installed on the Electric Vehicle (EV). In this method, EVs are charged while driving over the transmitters as they receive bursts of electric energy at the time of significant alignment between transmitters and receivers. Compared to the stationary charging method which involves parking the EV for long hours for a full charge, the dynamic charging method (i.e., DWPT) …


Career Prospects And Resources Of Domestic Engineering Doctoral Students, Laura A. Gelles Dec 2019

Career Prospects And Resources Of Domestic Engineering Doctoral Students, Laura A. Gelles

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Career prospects are a motivating factor for entry and retention of doctoral students, especially in the discipline of engineering. While doctoral student training provides them with highly specialized skills to be an independent researcher, they may not have the requisite skills or guidance to secure the job position of their choice. Therefore, it is important to provide doctoral students with opportunities, training, and information (i.e., resources) about different types of careers to not only ensure they are productive contributors of teaching and research, but also equip them for future career prospects. Research techniques based upon in-depth narrative interviews and combining …


Expression Systems For Synthetic Spider Silk Protein Production, Michaela R. Hugie Dec 2019

Expression Systems For Synthetic Spider Silk Protein Production, Michaela R. Hugie

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spider silk is a biodegradable and biocompatible natural material that is stronger than steel and more elastic than nylon. These properties make spider silk a desirable material for many commercial products, ranging from textiles to biomedical materials. Due to spiders’ cannibalistic and territorial nature it is impossible to farm them to produce spider silk at a high enough yield to meet product demands. Therefore, a bioengineered synthetic process is necessary to produce spider silk. Synthetic spider silk has been produced in bacteria, goats, yeast, plants, mammalian cells and silkworms, but none of these processes provided a commercially viable yield or …


A New Approach For Evaluating The Ductility, Volumetric Stiffness, And Permeability Of Cutoff Wall Backfill Materials, Jennifer Ostrowsky Dec 2019

A New Approach For Evaluating The Ductility, Volumetric Stiffness, And Permeability Of Cutoff Wall Backfill Materials, Jennifer Ostrowsky

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The use of plastic concrete for cutoff walls in dams for remediation of seepage issues has become more widely used in the past 25 years, however, the in-situ material properties are still not well understood. The research presents a new testing procedure that combines two existing testing methods, triaxial shear and permeability testing. By developing this laboratory testing method, material properties of the cutoff wall backfill material can be more accurately examined and explained using changes in the permeability of the material to discern the ductility and stiffness.


Hydro-Climatic Changes And Corresponding Impacts On Agricultural Water Demand In The Ganges Delta Of Bangladesh, Sonia Binte Murshed Dec 2019

Hydro-Climatic Changes And Corresponding Impacts On Agricultural Water Demand In The Ganges Delta Of Bangladesh, Sonia Binte Murshed

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Ganges Delta in Bangladesh, a transboundary rural river basin, is an example of water-related calamities due to natural and human-induced stresses. It is an agriculture-dominated area with the presence of Sundarbans mangrove forest. Recently this area is facing unfavorable conditions due to limitations in quantity, quality, and timing of available freshwater. As a result, floods, droughts, water scarcity, stream depletion, salinity intrusion, excessive sedimentation are becoming common phenomena. These calamities are making this area unsuitable for agriculture and vulnerable to the Sundarbans’ ecosystem. This study aims to provide technical insight into issues related to water scarcity and projected agricultural …


Agent-Based Model To Manage Household Water Use Through Social-Environmental Strategies Of Encouragement And Peer Pressure, Ryan James Aug 2019

Agent-Based Model To Manage Household Water Use Through Social-Environmental Strategies Of Encouragement And Peer Pressure, Ryan James

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Inelastic price responses, demand hardening, and poor public awareness reduce the effectiveness of demand side strategies on water savings. This project quantified phycological household’s factors of attitudes, peer support, opportunities on water conservation with two social-environmental management strategies of encouragement and peer pressure. An agent-based model was populated with data for Logan, Utah using surveys, municipal billing, aerial imagery, weather monitoring stations, and flow, frequency, and durations of appliance use data. Results indicated those households with higher attitudes, peer support and opportunities saved the most water while peer pressure saved more than encouragement when using small and diverse social networks …


Spiderworms: Using Silkworms As Hosts To Produce A Hybrid Silkworm-Spider Silk Fiber, Ana Laura Licon Aug 2019

Spiderworms: Using Silkworms As Hosts To Produce A Hybrid Silkworm-Spider Silk Fiber, Ana Laura Licon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spider silk has received significant attention due to its fascinating mechanical properties. Given the solitary and cannibalistic behavior of spiders, spider silk farming is impractical. Unlike spiders, silkworms are capable of producing large quantities of a fibrous product in a manner mimetic to spiders, and there already exists an industry to process cocoons into threads and textiles for many applications. The combination of silk farming (sericulture), a millennia old practice, and modern advancements in genetic engineering has given rise to an innovative biomaterial inspired by nature; transgenic silkworm silk.

This project focuses on the creation of chimeric silkworm-spider silk fibers …


Spectral, Energy And Computation Efficiency In Future 5g Wireless Networks, Haijian Sun Aug 2019

Spectral, Energy And Computation Efficiency In Future 5g Wireless Networks, Haijian Sun

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wireless technology has revolutionized the way people communicate. From first generation, or 1G, in the 1980s to current, largely deployed 4G in the 2010s, we have witnessed not only a technological leap, but also the reformation of associated applications. It is expected that 5G will become commercially available in 2020. 5G is driven by ever-increasing demands for high mobile traffic, low transmission delay, and massive numbers of connected devices. Today, with the popularity of smart phones, intelligent appliances, autonomous cars, and tablets, communication demands are higher than ever, especially when it comes to low-cost and easy-access solutions.

Existing communication architecture …


Isentropic Efficiency And Theoretical Analysis Of The Planetary Rotor Expander, Joseph L. James Aug 2019

Isentropic Efficiency And Theoretical Analysis Of The Planetary Rotor Expander, Joseph L. James

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Expanders allow pressurized fluids to undergo a pressure decrease in a controlled environment via volumetric growth to extract fluid energy. There are many types of expanders, and the objective of this thesis is to model the efficiencies of the planetary rotor expander (PRE), a century-old design undeveloped due to insufficient manufacturing capabilities (until recently). Geometric relationships are derived and mathematical models are generated to determine the efficiency of the PRE as a function of design variables. Two industrially relevant case studies show that, to maximize isentropic efficiency, the planetary rotor expander (PRE) rotational frequency is maximized and rotor geometry optimized.


Characterization Of Biofilms In A Synthetic Rhizosphere Using Hollow Fiber Root-Mimetic Systems, Michelle Bonebrake Aug 2019

Characterization Of Biofilms In A Synthetic Rhizosphere Using Hollow Fiber Root-Mimetic Systems, Michelle Bonebrake

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The area around a plant’s roots hosts a complex and diverse microbial community. This environment can include a large number of bacteria that live on the surface of the root and benefit from the nutrients that the roots exude into the soil. These microbes can in turn be beneficial to the plant by protecting the roots from harmful fungi or stressful environmental conditions such as drought. In this thesis, several root-mimetic systems (RMSs) were developed for the study and growth of plant-beneficial bacteria in the laboratory environment. The RMS uses a porous hollow fiber used in hemodialysis as a surface …


Investigation Of Graphene Interconnections For Multifunctional Reconfigurable Antenna Beam Steering, Joshua R. Perkins Aug 2019

Investigation Of Graphene Interconnections For Multifunctional Reconfigurable Antenna Beam Steering, Joshua R. Perkins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In high frequency, high-performance wireless communications, direct line of sight antennas are common. The issue with the line of sight antennas is the need to redirect the physical antenna to achieve the best possible reception. Classical redirections are done by mechanical movements: hand tuning and motors. Our multi-functional re-configurable antenna (MRA) concept allows for electrical and non-mechanical antenna reorientation. This work investigates two important concepts in the development and enhancement of future MRA devices: special, non-interfering, control signal circuitry and nano-sized switching devices that are controlled by the special circuitry. The investigation was conducted with the use of commercially available …


Generalization Of Signal Point Target Code, Md Munibun Billah Aug 2019

Generalization Of Signal Point Target Code, Md Munibun Billah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Detecting and correcting errors occurring in the transmitted data through a channel is a task of great importance in digital communication. In Error Correction Coding (ECC), some redundant data is added with the original data while transmitting. By exploiting the properties of the redundant data, the errors occurring in the data from the transmission can be detected and corrected. In this thesis, a new coding algorithm named Signal Point Target Code has been studied and various properties of the proposed code have been extended.

Signal Point Target Code (SPTC) uses a predefined shape within a given signal constellation to generate …


Design Of Capacitive Wireless Power Transfer Systems With Enhanced Power Density And Stray Field Shielding, Ujjwal Pratik Aug 2019

Design Of Capacitive Wireless Power Transfer Systems With Enhanced Power Density And Stray Field Shielding, Ujjwal Pratik

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wireless power transfer is becoming relevant today because of its effectiveness and convenience. It has been employed into consumer electronics such as cellular charging and electric vehicle charging. In general, inductive wireless power transfer (IPT) is mostly used for WPT. IPT requires coils and power transfer enhancing material such as ferrite to transfer power. However, Capacitive wireless Power Transfer (CPT) appears as an alternative because it requires cost effective and light metal plate couplers. Among CPT couplers, Vertical (stacked) Four-Plate Coupler (V4PC) structure offers the advantage of higher input and output self-capacitances, rotational misalignment.

Safety is one of the most …


Parametric Study Of Mixture Component Contributions To Compressive Strength And Impact Energy Absorption Capacity Of A High Strength Cementitious Mix With No Coarse Aggregate, Md. Abdullah Al Sarfin Aug 2019

Parametric Study Of Mixture Component Contributions To Compressive Strength And Impact Energy Absorption Capacity Of A High Strength Cementitious Mix With No Coarse Aggregate, Md. Abdullah Al Sarfin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research project has been undertaken to produce and characterize the behavior of High Strength Cementitious Mix (HSCM), which has considerably higher compressive strength compared to conventional concrete. Components of HSCM are cement, silica fume, sand, water, and high range water reducer. The material is tested for compressive strength and impact energy absorption capacity while the amount of above mentioned components are varied parametrically. The effect of these parameters are extensively studied and trends are reported. Finally, this research projects attempts to find correlations among compressive strength, compressive toughness, and impact toughness. Limitations of the experimental program are discussed and …


Angles-Only Ekf Navigation For Hyperbolic Flybys, Iggy Matheson Aug 2019

Angles-Only Ekf Navigation For Hyperbolic Flybys, Iggy Matheson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Space travelers in science fiction can drop out of hyperspace and make a pinpoint landing on any strange new world without stopping to get their bearings, but real-life space navigation is an art characterized by limited information and complex mathematics that yield no easy answers. This study investigates, for the first time ever, what position and velocity estimation errors can be expected by a starship arriving at a distant star - specifically, a miniature probe like those proposed by the Breakthrough Starshot initiative arriving at Proxima Centauri. Such a probe consists of nothing but a small optical camera and a …


Multiple Imu Sensor Fusion For Suas Navigation And Photogrammetry, Matthew Givens Aug 2019

Multiple Imu Sensor Fusion For Suas Navigation And Photogrammetry, Matthew Givens

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Inertial measurement units (IMUs) are devices that sense accelerations and angular rates in 3D so that vehicles and other devices can estimate their orientations, positions, and velocities. While traditionally large, heavy, and costly, using mechanical gyroscopes and stabilized platforms, the recent development of micro-electromechanical sensor (MEMS) IMUs that are small, light, and inexpensive has led to their adoption in many everyday systems such as cell phones, video game controllers, and commercial drones. MEMS IMUs, despite their advantages, have major drawbacks when it comes to accuracy and reliability. The idea of using more than one of these sensors in an array, …


Radiation Pattern Reconfigurable Horn Antenna Based On Parasitic Layer Concept, Mehmet Tanagardi Aug 2019

Radiation Pattern Reconfigurable Horn Antenna Based On Parasitic Layer Concept, Mehmet Tanagardi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In recent years, multi-functional reconfigurable antennas (MRA) has attracted much attention in wireless communication. The reconfigurable antenna can adapt itself with changing system conditions, and it can provide different multi-functionalities which can give better system performances. Instead of using multiple antennas, a single reconfigurable antenna can provide the same performance and occupy less space. By using the parasitic layer technique, an antenna can be turned into a reconfigurable antenna. The main objective of this thesis is to study radiation pattern reconfiguration of the horn antenna by using the parasitic layer concept. The MRA consists of a single horn, dielectric loaded …


Exploring The Capacity Of Bacteria For Natural Product Biosynthesis, Ozkan Fidan Aug 2019

Exploring The Capacity Of Bacteria For Natural Product Biosynthesis, Ozkan Fidan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation is focused on exploring the potential of bacteria for the biosynthesis of natural products with the purposes of generating novel natural product derivatives and of improving the titer of pharmaceutically important natural products.

A wide variety of compounds from various sources have been historically used in the treatment and prevention of diseases. Natural products as a major source of new drugs are extensively explored due to their huge structural diversity and promising biological activities such as antimicrobial, anticancer, antifungal, antiviral and antioxidant properties. For instance, penicillin as an early-discovered antimicrobial agent has saved millions of lives, indicating the …


Full-Pose Estimation And Tracking Control For A Multi-Rotor Aircraft Package Exchange, Trent P. Smith Aug 2019

Full-Pose Estimation And Tracking Control For A Multi-Rotor Aircraft Package Exchange, Trent P. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In this work, research to develop algorithms for a package exchange maneuver between two quad-rotor aircraft is presented. First, the development of tools used for this research is discussed. Second, a controller is designed that synchronizes the flight paths and motion of two quad-rotor robots. The controller is used to guide a designated follower quad-rotor to follow a leader aircraft’s position and orientation. The follower aircraft is equipped with a simple mechanical manipulator to compensate for limitations in the aircrafts maneuverability. finally, a sensor architecture study for relative navigation of Unmanned Aerial Vehicles (UAV) is presented. The architecture study presents …