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All Graduate Theses and Dissertations

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Full-Text Articles in Engineering

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 ...


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 ...


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 ...


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.


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


Tackling Choke Point Induced Performance Bottlenecks In A Near-Threshold Gpgpu, Tahmoures Shabanian Aug 2018

Tackling Choke Point Induced Performance Bottlenecks In A Near-Threshold Gpgpu, Tahmoures Shabanian

All Graduate Theses and Dissertations

Over the last decade, General Purpose Graphics Processing Units (GPGPUs) have garnered a substantial attention in the research community due to their extensive thread-level parallelism. GPGPUs provide a remarkable performance improvement over Central Processing Units (CPUs), for highly parallel applications. However, GPGPUs typically achieve this extensive thread-level parallelism at the cost of a large power consumption. Consequently, Near-Threshold Computing (NTC) provides a promising opportunity for designing energy-efficient GPGPUs (NTC-GPUs). However, NTC-GPUs suffer from a crucial Process Variation (PV)-inflicted performance bottleneck, which is called Choke Point. Choke Point is defined as one or small group of gates which is affected ...


Development And Optimization Of A Produced Water, Biofilm Based Microalgae Cultivation System For Biocrude Conversion With Hydrothermal Liquefaction, Benjamin L. Peterson Aug 2018

Development And Optimization Of A Produced Water, Biofilm Based Microalgae Cultivation System For Biocrude Conversion With Hydrothermal Liquefaction, Benjamin L. Peterson

All Graduate Theses and Dissertations

Extraction of oil and gas in Utah’s Uintah Basin results in large quantities of wastewater, or produced water, with nutrients and residual organic chemical that represent a significant resource for producing energy-related and value-added products. Produced water was obtained as a biomass producing nutrient source from industries operating in Utah’s Uintah Basin. Within the Uintah Basin (defined as Uintah and Duchesne Counties within Utah) approximately 93 million barrels of water were produced in 2013 while only 11% of the water was disposed of through evaporation, with the national average at 2%. The rest is reinjected into the subsurface ...


Advancing Methods To Quantify Actual Evapotranspiration In Stony Soil Ecosystems, Kshitij Parajuli Aug 2018

Advancing Methods To Quantify Actual Evapotranspiration In Stony Soil Ecosystems, Kshitij Parajuli

All Graduate Theses and Dissertations

Water is undeniably among the most important natural resources and the most critical in semi-arid regions like the Intermountain West of the United States. Such regions are characterized by low precipitation, the majority of which is transferred to the atmosphere from the soil and vegetation as evapotranspiration (ET). Quantification of ET is thus crucial for understanding the balance of water within the region, which is important for efficiently planning the available water resources. This study was motivated towards advancing the estimation of actual ET (ETA) in mountain ecosystems, where the variation in different types of vegetation and non-uniformity of ...


Water Entry Cavity Dynamics, Nathan B. Speirs Aug 2018

Water Entry Cavity Dynamics, Nathan B. Speirs

All Graduate Theses and Dissertations

When a sphere or a stream of water hits the surface of a pool of water and enters a crater or air cavity often forms. This topic has been studied, both formally and informally, for a long time. This dissertation investigates four areas of water impact that are still poorly understood using high-speed photography. First, it examines a stream of droplets impacting on a pool of water, similar to a faucet drizzling into a full bucket. For these types of impacts we predict the depth, diameter, velocity, and shape of the cavities that the droplet stream forms. Second, it examines ...


Uncertainty Quantification And Sensitivity Analysis Of Multiphysics Environments For Application In Pressurized Water Reactor Design, Cole David Blakely Aug 2018

Uncertainty Quantification And Sensitivity Analysis Of Multiphysics Environments For Application In Pressurized Water Reactor Design, Cole David Blakely

All Graduate Theses and Dissertations

The most common design among U.S. nuclear power plants is the pressurized water reactor (PWR). The three primary design disciplines of these plants are system analysis (which includes thermal hydraulics), neutronics, and fuel performance. The nuclear industry has developed a variety of codes over the course of forty years, each with an emphasis within a specific discipline. Perhaps the greatest difficulty in mathematically modeling a nuclear reactor, is choosing which specific phenomena need to be modeled, and to what detail.

A multiphysics computational environment provides a means of advancing simulations of nuclear plants. Put simply, users are able to ...


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 ...


Design And Control Of Series Resonant Converters For Dc Current Power Distribution Applications, Hongjie Wang Aug 2018

Design And Control Of Series Resonant Converters For Dc Current Power Distribution Applications, Hongjie Wang

All Graduate Theses and Dissertations

With the growth of renewable energy usage and energy storage adoption in recent decades, people have started to reevaluate the possible roles of dc systems in current and future electrical systems. The dc voltage distribution has been applied in various applications, such as data centers and aircraft industry, for high efficiency and power density. However, for some applications such as subsea gas and oil fields, and ocean observatory systems, the dc current distribution is preferred over dc voltage distribution for its low cost and robustness against cable faults. Design and control of dc power distribution systems for different applications is ...


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 ...


Attracting Secondary Students To Stem Using A Summer Engineering Camp, Murad Mahmoud Aug 2018

Attracting Secondary Students To Stem Using A Summer Engineering Camp, Murad Mahmoud

All Graduate Theses and Dissertations

The purpose of this research was to study the benefits of having middle school students attend a summer camp focused on the fields of Science, Technology, Engineering and Mathematics (STEM). A lot of research funding is being used in such camps to help get more students into STEM fields as there is a lack of graduates in those fields. Therefore, it is important to understand the benefits and effectiveness of such camps.

Students, teachers and parents were involved in this research. Students and teachers attended a one-week engineering camp at Utah State University while parents were involved via a blog ...


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 ...


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 ...


Split Latency Allocator: Process Variation-Aware Register Access Latency Boost In A Near-Threshold Graphics Processing Unit, Asmita Pal Aug 2018

Split Latency Allocator: Process Variation-Aware Register Access Latency Boost In A Near-Threshold Graphics Processing Unit, Asmita Pal

All Graduate Theses and Dissertations

Over the last decade, Graphics Processing Units (GPUs) have been used extensively in gaming consoles, mobile phones, workstations and data centers, as they have exhibited immense performance improvement over CPUs, in graphics intensive applications. Due to their highly parallel architecture, general purpose GPUs (GPGPUs) have gained the foreground in applications where large data blocks can be processed in parallel. However, the performance improvement is constrained by a large power consumption. Likewise, Near Threshold Computing (NTC) has emerged as an energy-efficient design paradigm. Hence, operating GPUs at NTC seems like a plausible solution to counteract the high energy consumption. This work ...


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 ...


Evaluating The Impact Of External Carbon Source In Laboratory-Based Denitrification Rate Experiments, Jared Richens May 2018

Evaluating The Impact Of External Carbon Source In Laboratory-Based Denitrification Rate Experiments, Jared Richens

All Graduate Theses and Dissertations

Limitations in the quality of transformation rates used with water quality models such as QUAL2K have led to the need to identify methods that can effectively and accurately determine these rates. During the early stages of method development of a Utah Department of Environmental Quality (Utah DEQ) funded project seeking to identify such methods, it was determined that under certain situations external carbon amendment may be required to successfully determine denitrification rates.

The focus of this study was to evaluate the potential impacts that introducing external carbon sources may have on estimating the laboratory denitrification rates resulting from these methods ...


Thrust Augmented Nozzle For A Hybrid Rocket With A Helical Fuel Port, Joel H. Marshall May 2018

Thrust Augmented Nozzle For A Hybrid Rocket With A Helical Fuel Port, Joel H. Marshall

All Graduate Theses and Dissertations

A thrust augmented nozzle for hybrid rocket systems is investigated. The design lever-ages 3-D additive manufacturing to embed a helical fuel port into the thrust chamber of a hybrid rocket burning gaseous oxygen and ABS plastic as propellants. The helical port significantly increases how quickly the fuel burns, resulting in a fuel-rich exhaust exiting the nozzle. When a secondary gaseous oxygen flow is injected into the nozzle downstream of the throat, all of the remaining unburned fuel in the plume spontaneously ignites. This secondary reaction produces additional high pressure gases that are captured by the nozzle and significantly increases the ...


Advancing The Implementation Of Hydrologic Models As Web-Based Applications, Prasanna Dahal May 2018

Advancing The Implementation Of Hydrologic Models As Web-Based Applications, Prasanna Dahal

All Graduate Theses and Dissertations

Deeper understanding of relationships between flow in river sand various hydrologic elements such as rainfall, land use, and soil type is imperative to solve water related problems like droughts and floods. Advanced computer models are becoming essential in helping us understand such relationships. However, preparing such models requires huge investment of time and resources, much of which are concentrated on acquisition and curation of data. This work introduces agree and open source web Application (web App) that provides researchers with simplified access to hydrological data and modeling functionality. The web App helps in the creation of both hydrologic models, and ...