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All Graduate Theses and Dissertations

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Full-Text Articles in Engineering

Development And Testing Of Additively Manufactured Aerospike Nozzles For Small Satellite Propulsion, Isaac W. Armstrong May 2019

Development And Testing Of Additively Manufactured Aerospike Nozzles For Small Satellite Propulsion, Isaac W. Armstrong

All Graduate Theses and Dissertations

Automatic altitude compensation has been a holy grail of rocket propulsion for decades. Current state-of-the-art bell nozzles see large performance decreases at low altitudes, limiting rocket designs, shrinking payloads, and overall increasing costs. Aerospike nozzles are an old idea from the 1960’s that provide superior altitude-compensating performance and enhanced performance in vacuum, but have survivability issues that have stopped their application in satellite propulsion systems. A growing need for CubeSat propulsion systems provides the impetus to study aerospike nozzles in this application. This study built two aerospike nozzles using modern 3D metal printing techniques to test aerospikes at a ...


Investigation Of Thermoplastic Polymers And Their Blends For Use In Hybrid Rocket Combustion, Spencer D. Mathias May 2019

Investigation Of Thermoplastic Polymers And Their Blends For Use In Hybrid Rocket Combustion, Spencer D. Mathias

All Graduate Theses and Dissertations

This thesis set out to find a blend of thermoplastics that had better combustion properties than the current ABS (acrylonitrile butadiene styrene) plastic or “Lego TM plastic” used by Utah State University. The current work is in an effort to eliminate toxic propellants from small space applications. High and low density polyethylene plastics were used because they are common plastic waste items. In this way rocket fuel can be made from these items to reduce the waste found in landfills. Three plastics were considered for replacement and as mixture components with the ABS plastic, namely low and high density polyethylene ...


Hydrodeoxygenation Of Pinyon-Juniper Catalytic Pyrolysis Oil, Hossein Jahromi May 2019

Hydrodeoxygenation Of Pinyon-Juniper Catalytic Pyrolysis Oil, Hossein Jahromi

All Graduate Theses and Dissertations

Catalytic hydrodeoxygenation (HDO), is an effective process to convert oxygenated compounds to hydrocarbons. This process is widely used for improving the negative properties of biomass-derived pyrolysis oils (bio-oils) such as high acidity, poor stability, and low heating value. During this process oxygen is removed from the bio-oil in the form of water, thus the liquid product of HDO process consists of aqueous phase and hydrocarbon phase that can be easily separated. Synthesis of efficient HDO catalyst has been a major challenge in the field of bio-oil upgrading. Red mud, which is an alkaline waste from alumina industry was used to ...


Pressure Loss Coefficients For Large Mitered Elbows With Diameters Ranging From 36-Inches To 144-Inches, Hayden J. Coombs May 2019

Pressure Loss Coefficients For Large Mitered Elbows With Diameters Ranging From 36-Inches To 144-Inches, Hayden J. Coombs

All Graduate Theses and Dissertations

When designing a pipeline system, it is important to understand the pressure losses that will occur within the system. One common source of pressure loss is from elbow pipe fittings. There is extensive research available for pressure loss coefficients of elbow pipe fittings, but the research is derived from elbows with relatively smaller pipe diameters. The purpose of this research is to investigate pressure losses associated with larger diameter mitered elbows (36-inches to 144-inches). The dimensions for all mitered elbows considered in this research follow ANSI/AWWA C208-17 recommendations (AWWA 2017).

Due to the large size of the mitered elbows ...


Application Of Winslamm To Evaluate The Effect Of Green Infrastructure Implementation In Northern Utah, Rosa A. Fernández Velásquez Dec 2018

Application Of Winslamm To Evaluate The Effect Of Green Infrastructure Implementation In Northern Utah, Rosa A. Fernández Velásquez

All Graduate Theses and Dissertations

This study provides an evaluation of the performance of the WinSLAMM model in two cities of northern Utah, a region in which it has not been validated to date. Runoff volumes for a series of events from 2015 to 2017 were calculated for six study areas. These results were compared to model outputs to evaluate the prediction accuracy. The model performed poorly when default parameters where used, as expected. Thus, the calibration of runoff coefficient was done with local data. Total suspended solids (TSS), total phosphorus (TP) and total dissolved phosphorus (TDP) were also evaluated and calibrations were developed. The ...


Production And Purification Of Synthetic Minor Ampullate Silk Proteins, Danielle A. Gaztambide Dec 2018

Production And Purification Of Synthetic Minor Ampullate Silk Proteins, Danielle A. Gaztambide

All Graduate Theses and Dissertations

Spider silks are incredible natural materials that have a wide variety of properties that can rival or outperform even common synthetic materials like Nylon and Kevlar. As nature’s architects, orb-weaving spiders spin seven different silks that are used for very specific roles throughout the spider’s lifecycle. These silks are comprised of proteins called spidroins. Each of these spidroins has evolved to have properties such as strength and/or stretch that make these silks successful and highly adapted in their designated roles in web construction, prey capture and reproduction.

This study involves the production of minor ampullate silk by ...


Autonomous Trajectory Planning For Satellite Rpo And Safety Of Flight Using Convex Optimization, Nicholas G. Ortolano Dec 2018

Autonomous Trajectory Planning For Satellite Rpo And Safety Of Flight Using Convex Optimization, Nicholas G. Ortolano

All Graduate Theses and Dissertations

Optimal trajectory planning methods that implement convex optimization techniques are applied to the area of satellite rendezvous and proximity operations. This involves the development of linearized relative orbital motion dynamics and constraints for two satellites, where one maintains a near-circular reference orbit. The result is formulated as a convex optimization problem, where the objective is to minimize the amount of fuel required to transfer from a given initial condition to the desired final conditions. A traditional rendezvous and proximity operations scenario is analyzed, which includes examples of initial approach, inspection, final approach, and docking trajectories. This scenario may include trajectory ...


Study Of The 3w Measurement Of The In-Plane And The Cross-Plane Thermal Properties On Anisotropic Thin Film Materials, Daxi Zhang Dec 2018

Study Of The 3w Measurement Of The In-Plane And The Cross-Plane Thermal Properties On Anisotropic Thin Film Materials, Daxi Zhang

All Graduate Theses and Dissertations

Due to the size of the nano-scale and micro-scale materials, traditional method for measuring the thermal properties of the bulk materials cannot be applied. The 3 OmegaMethod was developed by D. G. Cahill in the early 90s. It was used extensively to measure the thermal properties of thin film dielectric materials. Compare with other simulations or experimental methods, the 3 Omega Method has many advantages. Previous research has indicate that the 3 Omega method is capable of measuring the cross-plane thermal conductivity of thin film materials. In extension, an alternative improvement for measurement of the in-plane thermal conductivity and calculating ...


Investigating Rapid Concrete Repair Materials And Admixtures, Ivan Quezada Dec 2018

Investigating Rapid Concrete Repair Materials And Admixtures, Ivan Quezada

All Graduate Theses and Dissertations

This dissertation presents a literature review of the state-of-practice for the use of IC in concrete mixtures and how structural engineers and construction engineers can adapt IC to their present and future work. Current high early strength concrete mixtures have natural cracking and shrinkage problems due to the high content of cementitious material or their chemical components. Using IC allows for early strength, enhanced durability, reduced shrinkage and a better curing by providing water that can be absorbed by the cement past after the final set. Rapid hydration and high early strength Portland cement and calcium sulfoaluminate (CSA) concretes are ...


Droplet Impact Onto Super-Hydrophobic Surfaces And Determining The Response To Heat And Light Of Terrestrial Cyanobacteria, Benjamin B. Lovett Dec 2018

Droplet Impact Onto Super-Hydrophobic Surfaces And Determining The Response To Heat And Light Of Terrestrial Cyanobacteria, Benjamin B. Lovett

All Graduate Theses and Dissertations

This thesis examines droplets striking water repelling surfaces as well as the movement of a soil based bacteria under various light and heat conditions. Droplet impact studies have shown that introducing a macroscopic feature to a water repelling surface can reduce the amount of time that droplet is in contact with the surface. By manipulating water droplets to impact different sized needles at varying speeds, we present how a needle can induce a similar reduction in the residence time of the droplet to more widely studied features. Results show the spreading and lift-off characteristics of the droplet are dependent on ...


Additively-Manufactured Hybrid Rocket Consumable Structure For Cubesat Propulsion, Britany L. Chamberlain Dec 2018

Additively-Manufactured Hybrid Rocket Consumable Structure For Cubesat Propulsion, Britany L. Chamberlain

All Graduate Theses and Dissertations

Three-dimensional, additive printing has emerged as an exciting new technology for the design and manufacture of small spacecraft systems. Using 3-D printed thermoplastic materials, hybrid rocket fuel grains can be printed with nearly any cross-sectional shape, and embedded cavities are easily achieved. Applying this technology to print fuel materials directly into a CubeSat frame results in an efficient, cost-effective alternative to existing CubeSat propulsion systems. Different 3-D printed materials and geometries were evaluated for their performance as propellants and as structural elements. Prototype "thrust columns" with embedded fuel ports were printed from a combination of acrylonitrile utadiene styrene (ABS) and ...


Experimental Investigation Of A Green Hybrid Thruster Using A Moderately Enriched Compressed Air As The Oxidizer, Marc Anthony Bulcher Dec 2018

Experimental Investigation Of A Green Hybrid Thruster Using A Moderately Enriched Compressed Air As The Oxidizer, Marc Anthony Bulcher

All Graduate Theses and Dissertations

A hybrid rocket is a propulsion system that uses propellants in two different phases, typically a solid fuel inside the combustion chamber and a separate gaseous or liquid oxidizer stored in a tank. Hybrid rockets are an area of research interest because of their low explosive risk, inexpensive components, and high degree of reliability. In the Propulsion Research Laboratory at Utah State University, pure oxygen is among the top choice for hybrid rocket oxidizers due to its low cost and ease of storage. When paired with a solid fuel known as ABS (acrylonitrile butadiene styrene) plastic, specific impulse values exceed ...


Production And Biocompatibility Of Spider Silk Proteins In Goat Milk, Richard E. Decker Jr Dec 2018

Production And Biocompatibility Of Spider Silk Proteins In Goat Milk, Richard E. Decker Jr

All Graduate Theses and Dissertations

Due to its strength, flexibility, and biocompatibility, spider silk is a highly appealing material for applications in the medical field. Unfortunately, natural spider silk is difficult to obtain in large quantities because spiders are territorial and cannibalistic, making them impractical to farm. Synthetic spider silk proteins produced by transgenic hosts such as bacteria and goats have made it possible to obtain the quantities of spider silk needed to study it more fully and to investigate its potential uses. The spider silk proteins produced in our laboratory do not have an optimal purification method to remove all of the non-biocompatible contaminants ...


Non-Contact Evaluation Methods For Infrastructure Condition Assessment, Sattar Dorafshan Dec 2018

Non-Contact Evaluation Methods For Infrastructure Condition Assessment, Sattar Dorafshan

All Graduate Theses and Dissertations

The United States infrastructure, e.g. roads and bridges, are in a critical condition. Inspection, monitoring, and maintenance of these infrastructure in the traditional manner can be expensive, dangerous, time-consuming, and tied to human judgment (the inspector). Non-contact methods can help overcoming these challenges. In this dissertation two aspects of non-contact methods are explored: inspections using unmanned aerial systems (UASs), and conditions assessment using image processing and machine learning techniques. This presents a set of investigations to determine a guideline for remote autonomous bridge inspections.


Identification And Engineering Of Nonribosomal Peptide Biosynthetic Systems, Fuchao Xu Dec 2018

Identification And Engineering Of Nonribosomal Peptide Biosynthetic Systems, Fuchao Xu

All Graduate Theses and Dissertations

This research focuses on the understanding and engineering of nonribosomal peptide biosynthetic pathways in Streptomyces coelicolor CH999, Escherichia coli BAP1 and Saccharomyces cerevisiae BJ5464-NpgA. The biosynthetic systems of indigoidine from bacteria and beauvericin/bassianolide from fungi were studied in this research. The production of these valuble products was significantly increased by enhancing their synthetic pathway with metabolic engineering approaches.

Indigoidine is a bacterial natural product with antioxidant and antimicrobial activities. Its bright blue color resembles the industrial dye indigo, thus representing a new natural blue dye that may find uses in industry. Indigo is a dark blue crystalline powder and ...


Sparse Signal Recovery Based On Compressive Sensing And Exploration Using Multiple Mobile Sensors, Mohammad Shekaramiz Dec 2018

Sparse Signal Recovery Based On Compressive Sensing And Exploration Using Multiple Mobile Sensors, Mohammad Shekaramiz

All Graduate Theses and Dissertations

The work in this dissertation is focused on two areas within the general discipline of statistical signal processing. First, several new algorithms are developed and exhaustively tested for solving the inverse problem of compressive sensing (CS). CS is a recently developed sub-sampling technique for signal acquisition and reconstruction which is more efficient than the traditional Nyquist sampling method. It provides the possibility of compressed data acquisition approaches to directly acquire just the important information of the signal of interest. Many natural signals are sparse or compressible in some domain such as pixel domain of images, time, frequency and so forth ...


Thallium Removal From Drinking Water Using Pyrolusite Filter Media, Erin R. Andersen Dec 2018

Thallium Removal From Drinking Water Using Pyrolusite Filter Media, Erin R. Andersen

All Graduate Theses and Dissertations

Thallium (Tl) is a rare heavy metal in drinking water, but its extreme toxicity makes its removal crucial to consumer health. Traditional treatment methods do not work for Tl in sources with high concentrations of ions like calcium (Ca+2) and potassium (K+), as they are removed preferentially to Tl. A treatment method that specifically targets Tl must be applied. Pilot studies conducted in Park City Utah found that pyrolusite, a manganese oxide ore, will remove Tl to very low concentrations in the presence of competing ions but because this method is not common, further study was required. This study ...


Demand Disaggregation For Non-Residential Water Users In The City Of Logan, Utah, Usa, Nour Aldin Mahmoud Attaallah Dec 2018

Demand Disaggregation For Non-Residential Water Users In The City Of Logan, Utah, Usa, Nour Aldin Mahmoud Attaallah

All Graduate Theses and Dissertations

Non-residential users contribute to a significant portion of the total water delivered by water supplying agencies. However, a very limited number of studies have attempted to investigate the water use behavior of non-residential users. With the emergence of newer “smart” meters, water use now can be measured and recorded at a very high temporal frequency. Smart meters can help determine total water use, timing, and component end uses to better understand water use practices by non-residential users.

Water end use disaggregation is the process of separating the water used by each fixture or process within a facility. This is useful ...


Spatial Ability Degradation In Undergraduate Mechanical Engineering Students During The Winter Semester Break, Benjamin J. Call Dec 2018

Spatial Ability Degradation In Undergraduate Mechanical Engineering Students During The Winter Semester Break, Benjamin J. Call

All Graduate Theses and Dissertations

Spatial ability represents our ability to mentally arrange, rotate, and explore objects in multiple dimensions. This ability has been found to be important for engineers and engineering students. Past research has shown that many interventions can be created to boost an individual’s spatial ability. In fact, past research has indicated that engineering students significantly increase in spatial ability without an intervention while they are enrolled in certain engineering courses. Some researchers have claimed that the spatial ability boosts are permanent after an intervention. However, most researchers do not check the validity of that claim with continued assessment after more ...


Supporting Adolescent Metacognition In Engineering Design Through Scripted Prompts From Peer Tutors: A Comparative Case Study, Kristin Marie Strong Dec 2018

Supporting Adolescent Metacognition In Engineering Design Through Scripted Prompts From Peer Tutors: A Comparative Case Study, Kristin Marie Strong

All Graduate Theses and Dissertations

In 2013, developers of the Next Generation Science Standards implemented national K -12 directives and elevated engineering design to the level of scientific inquiry. Teaching design, however, is challenging to educators due to the complex nature of design problems, which cannot be solved via simple algorithms. Solving design problems requires a more reflective and iterative approach that emphasizes metacognitive skills like planning, monitoring, and taking another person’s perspective. Educators are further challenged by children’s immature metacognitive skills, which may be insufficient to engage in the entire design process.

A qualitative study of paired seventh graders demonstrated a pragmatic ...


Development Of An Improved Low-Order Model For Propeller-Wing Interactions, Joshua Taylor Goates Dec 2018

Development Of An Improved Low-Order Model For Propeller-Wing Interactions, Joshua Taylor Goates

All Graduate Theses and Dissertations

For aircraft that have propellers mounted in front of the wings or tail, the prop wash produced by the propellers can have a strong influence on the aerodynamics of the aircraft. As the accelerated air from the propeller flows over the wings and tail, it can cause an alteration in the aerodynamic forces produced by those surfaces. Thus, an understanding of propeller-wing interactions is essential for the design and analysis of many aircraft.

There are multiple existing methods for analyzing the propeller-wing interactions. High order methods, such as wind tunnel testing or computational fluid dynamics, provide very accurate results but ...


Plume Contamination Measurements Of An Additively-Printed Gox/Abs Hybrid Thruster, David A. Brewer Aug 2018

Plume Contamination Measurements Of An Additively-Printed Gox/Abs Hybrid Thruster, David A. Brewer

All Graduate Theses and Dissertations

This thesis examines the impact of the physical contamination on optical surfaces of spacecraft by an ABS/GOX thruster. Plume contamination presents a significant operational hazard for spacecraft solar arrays and thermal control surfaces can lead to decreased power production and increased spacecraft temperatures. Historically, due to the lack of a reliable, on-demand, and multiple-use ignition methodology, hybrid rockets have never been previously considered for in-space propulsion. Recent advancements in hybrid rocket technologies, have made hybrid systems feasible for in space propulsion. However, prior to this study no research had ever been performed with regard to plume contamination effects due ...


Ultraviolet Diffraction Assisted Image Correlation (Uv-Daic) For Single-Camera 3d Strain Measurement At Extreme Temperatures, Ethan K. Nickerson Aug 2018

Ultraviolet Diffraction Assisted Image Correlation (Uv-Daic) For Single-Camera 3d Strain Measurement At Extreme Temperatures, Ethan K. Nickerson

All Graduate Theses and Dissertations

Digital Image Correlation (DIC) is a technique which uses images taken before and after deformation to determine displacement and strain data over the surface of the sample. In order to obtain this data for both in-plane as well as out-of-plane direction, multiple views of the sample are required. Typically, this is accomplished using multiple cameras, but it is possible to use diffraction gratings to bend the light coming from the specimen in order to allow a single camera to capture multiple views. This technique is referred to as Diffraction Assisted Image Correlation (DAIC) and has been previously demonstrated at room ...


Biomass And Phycocyanin From Oil And Natural Gas Extraction Produced Water Utilizing A Cyanobacteria Dominated Rotating Algal Biofilm Reactor (Rabr), Jonathan L. Wood Aug 2018

Biomass And Phycocyanin From Oil And Natural Gas Extraction Produced Water Utilizing A Cyanobacteria Dominated Rotating Algal Biofilm Reactor (Rabr), Jonathan L. Wood

All Graduate Theses and Dissertations

The production of cyanobacterial biofilm biomass and phycocyanin from Rotating Algal Biofilm Reactors utilizing undiluted produced water from oil and natural gas extraction as a culture medium was investigated in this study. Produced water is the largest waste stream generated by the oil and natural gas industries and represents a large volume of non-potable water that may be available for algae culture with minimal impact on freshwater resources. Combining the use of produced wastewater as culture medium with the production of high value algal pigments, such as phycocyanin, may increase the economic viability of algae culture and wastewater purification. High ...


The Effects Of Geometric And Stoichometric Change In Nanoparticles And Materials On Lattice Thermal Conductivity, W. Tanner Yorgason Aug 2018

The Effects Of Geometric And Stoichometric Change In Nanoparticles And Materials On Lattice Thermal Conductivity, W. Tanner Yorgason

All Graduate Theses and Dissertations

Thermal transport properties are critical for applications ranging from thermal management to energy conversion. Passive thermal management has been an area of study for over a century and has only grown as technology has advanced because it requires no additional energy to remove heat. Changing the nanostructure of the materials involved in passive heat transfer methods, either by geometric changes or stoichiometric changes, can greatly improve the effectiveness of this heat transfer method. In order to explore this further, this work employs LAMMPS molecular dynamics (MD) simulation software to calculate the lattice thermal conductivity (λp) of a nanoparticle (NP ...


Conformal Inkjet Printed Antennas For Small Spacecraft, Muhammadeziz Tursunniyaz Aug 2018

Conformal Inkjet Printed Antennas For Small Spacecraft, Muhammadeziz Tursunniyaz

All Graduate Theses and Dissertations

Although small spacecraft are small in size and light in weight compared to the conventional satellites, they can offer lots of possibilities for space exploration, scientific observation, data collection and telecommunication. Also, they cost a lot less money than the conventional satellites, and the scientific missions can be planned in a relatively short period of time by using the COTS (Commercial Off-The-Shelf) materials. However, there is a big challenge for the small spacecraft that is the limited surface area of the small spacecraft and the outnumbered components to be mounted on the surface of the small spacecraft. The most obvious ...


An Experimental Comparison Of Student Motivation Between Two Computational Thinking-Based Stem Activities: Vex-Based Automation And Robotics And A Quadcopter Activity, Cory J. Ortiz Aug 2018

An Experimental Comparison Of Student Motivation Between Two Computational Thinking-Based Stem Activities: Vex-Based Automation And Robotics And A Quadcopter Activity, Cory J. Ortiz

All Graduate Theses and Dissertations

The purpose of this study was to compare student motivation between two junior high level computational thinking based STEM curricular activities. These two activities were a newly developed quadcopter based curriculum and a VEX based curricular activity developed for Project Lead the Way’s Gateway to Technology – Automation and Robotics course. Student motivation was assessed using an assessment called My Class Activities which broke motivation into four constructs: interest, challenge, choice, and enjoyment.

This study assessed students in three schools in a northern Utah school district. Students were assessed after receiving each curriculum. Assessment responses were then coded and analyzed ...


Senior Computer Science Students’ Task And Revised Task Interpretation While Engaged In Programming Endeavor, Andreas Febrian Aug 2018

Senior Computer Science Students’ Task And Revised Task Interpretation While Engaged In Programming Endeavor, Andreas Febrian

All Graduate Theses and Dissertations

Developing a computer program is not an easy task. Studies reported that a large number of computer science students decided to change their major due to the extreme challenge in learning programming. Fortunately, studies also reported that learning various self-regulation strategies may help students to continue studying computer science. This study is interested in assessing students’ self-regulation, in specific their task understanding and its revision during programming endeavors. Task understanding is specifically selected because it affects the entire programming endeavor.

In this qualitative case study, two female and two male senior computer science students were voluntarily recruited as research participants ...


Quantifying Dominant Heat Fluxes In An Arctic Alaskan River With Mechanistic River Temperature Modeling, Tyler V. King Aug 2018

Quantifying Dominant Heat Fluxes In An Arctic Alaskan River With Mechanistic River Temperature Modeling, Tyler V. King

All Graduate Theses and Dissertations

Temperatures strongly affect physical, chemical, and biological processes in rivers and streams. The processes that influence river temperatures are known across most geographic regions, but the relative importance varies significantly. Little is known about what controls water temperature Arctic rivers, limiting our ability to understand the impacts of climate change. This dissertation addresses this knowledge gap by incorporating field measurements with river temperature modeling to estimate the relative importance of key factors that affect Arctic river temperatures. Results indicate that shortwave radiation (e.g., sunlight) and net longwave radiation are significant throughout an Arctic watershed in all flow conditions. In ...


On Thermal Bowing Of Concrete Sandwich Wall Panels With Flexible Shear Connectors, Fray Pozo Aug 2018

On Thermal Bowing Of Concrete Sandwich Wall Panels With Flexible Shear Connectors, Fray Pozo

All Graduate Theses and Dissertations

Thermal bowing, often referred as bulging or out-of-plane wall deflection, is a common issue on sandwich panel walls caused by a temperature differential between a building interior temperature and the environment. The stresses caused by temperature changes in concrete members are widely known in the practice of bridge design, but not on sandwich wall panels. For sandwich wall panel applications, it is common to have non-composite panels when the designer expects a high temperature gradient, what yields a less economical design, but reduces the bowing.

This project aimed to validate current assumptions regarding the heat flow in sandwich wall panels ...