Engineering Commons^™

Design And Construction Of A Tunable Light Source With Light Emitting Diodes For Photosynthetic Organisms, Nathan Phillipps

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis describes and documents the design and construction of a light source which is tunable and has the ability to mimic the spectral output of the sun in the photosynthetic active radiation range (400 - 700 nm). To adjust the spectral output at different wavelengths different types of LEDs were chosen and combined. This thesis describes the design, construction, testing, and suggestions for further improvements to this light source. The light source is comprised of 900 LEDs with 26 different peak wavelengths within the photosynthetically active radiation range. The light source is made tunable through the use of a …

Process Variation Aware Dram (Dynamic Random Access Memory) Design Using Block-Based Adaptive Body Biasing Algorithm, Satyajit Desai

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Process variation can be defined as the deviation of process parameters from its nominal specifications. Variation is induced by several fundamental effects resulting from inaccuracies in the manufacturing equipment. It is a combination of systematic effects (e.g., lithographic lens aberrations) and random effects (e.g., dopant density fluctuations). The effect of process variation becomes particularly important at smaller process nodes, where the variation accounts for a major percentage of nominal length or width of the device. Process variations translate to a wide range in performance metrics of current designs. As technology scales, these die variations are getting larger, significantly affecting performance …

A Multifunctional Solar Panel Antenna For Cube Satellites, Olutosin C. Fawole

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This work presented the design of a single antenna structure that can perform the functions of about four antennas. The antenna is to be applied on a new kind of very tiny satellites. These satellites are called CubeSats. In contrast to an ordinary antenna that works at a single frequency band, the antenna designed will be able to work at about three different usable frequencies. In addition, it will be possible to make the waves emitted by the antenna to have multiple senses of rotation or no rotation at all. The multiple functional capability of the antenna will lead to …

Transportation Network Resiliency: A Study Of Self-Annealing, Sunil Babu Pant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Disasters have the potential to hit any geographical location with or without warning. As such, it is desirable that transportation networks are able to withstand the adverse effect of disasters and maintain the normal functioning of all sectors of society. Resilient transportation networks are least affected by disruptions created by natural and manmade disasters and are still able function with an acceptable level of service. Such networks also have ability to return earlier from disrupted state to the normal functioning state. Resilience possessed by a transportation network measures the ability of networks to maintain functionality despite adverse conditions posed by …

Flow Characteristics Of Arced Labyrinth Weirs, Nathan A. Christensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The need to accommodate larger reservoir discharge events has prompted the improvement or replacement of existing spillways. One possible spillway modification is the use of an in-reservoir arced labyrinth weir in place of a linear weir. Arced labyrinth weirs can increase crest length (more cycles) and have improved hydraulic efficiency in non-channelized approach flow applications, compared to traditional labyrinth weir applications.

In this study, arced labyrinth weir flow characteristics were observed for eleven different laboratory-scale model geometries at the Utah Water Research Laboratory. Rating (C_d vs. H_T/P) data and observations were recorded for each configuration, and discharge …

Developing A Framework To Analyze The Effect Of Mobile Technology Within A Department Of Transportation, Devin Squire

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mobile technology has the potential to have a substantial impact on governmental agencies. In order to understand the effects of mobile technology within an agency, an analysis has to be performed. This thesis presents two mobile applications that were developed to address specific areas of concern within the Utah Department of Transportation. It then, using mobile-technology specific surveys, provides a framework for effect analysis following application implementation. This framework employs both user and developer surveys to obtain data necessary to, through statistical methods, determine either a positive or a negative application induced effect. The analysis process and survey development used …

Analysis Of Irrigation Decision Behavior And Forecasting Future Irrigation Decisions, Sanyogita Andriyas

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Farmers play a pivotal role in food production. To be economically successful, farmers must make many decisions during the course of a growing season about the allocation of inputs to production. For farmers in arid regions, one of these decisions on any given day is whether to irrigate. This research is the first of its kind to investigate the probable reasons that lead a farmer to make irrigation decisions and use those reasons/factors to forecast future irrigation decisions. This study can help water managers and canal operators to estimate short-term irrigation demands, thereby gaining information that might be useful to …

Laboratory Modeling Of Critical Hydraulic Conditions For The Initiation Of Piping, Mandie Swainston Fleshman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objective of this research is to provide fundamental understanding of the piping phenomenon. This will lead to practical solutions to the critical hydraulic conditions for piping that account for soil properties, direction of flow, stress condition and exit face conditions. In current geotechnical engineering practice, these factors are generally not considered. The critical hydraulic gradient is assumed to be only a function of the soil buoyant unit weight. In recent analyses, laboratory experiments, and field observations indicate that piping can be initiated at gradients much lower than the values predicted by the current practice. The current practice may be …

Biodiesel Production From Mixed Culture Algae Via A Wet Lipid Extraction Procedure, Ashik Sathish

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Development of renewable sources of energy has received significant interest due to the rising costs of energy and the environmental impact of using fossil fuels. Biodiesel production from renewable sources of oil has shown promise of helping to replace or reduce dependence on petroleum based diesel thereby reducing demand for crude oil. Microalgae have been considered as a strong candidate for the production of large quantities of renewable oil for biodiesel production.

Microalgae are single cell photosynthetic organisms that posses the capability to produce renewable oil at rates much faster than land based plants and crops. In addition, microalgae can …

An Analysis Of Traffic Sign Performance For The Establishment Of A Maintenance Plan, Wesley Bill Boggs

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

For a variety of reasons both within and outside the control of transportation agencies, there is a higher frequency of fatalities during nighttime hours than during daytime hours. In an effort to enhance visual cues for nighttime motorists, the Federal Highway Administration (FHWA) established the minimum maintained retroreflectivity levels. This retroreflective mandate required agencies or public officials that have jurisdiction over a traffic sign population to implement maintenance methods that would ensure signs were performing at or above the minimum levels. Retroreflectivity is a unique type of reflection that distinguishes itself by reflecting light back in the direction of the …

Performance Characterization Of Complex Fuel Port Geometries For Hybrid Rocket Fuel Grains, Andrew Bath

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Extensive research in hybrid rocket motors has taken place at the department of Mechanical and Aerospace Engineering at USU (Utah State University) in the last several years. USU has one of the few facilities in the country capable of static-test firing rocket motors on-campus, which allows for fast-paced testing and development not available elsewhere. Research has involved investigating propulsion devices for a range of applications, including micro-satellite thrusters, hot-gas generators, and even jet-assisted takeoff kick motors. Hybrid motors have the advantage of safety over any other chemical propulsion. Since the fuel and oxidizer are stored seperately, they are relatively inert …

Closed-Loop Thrust And Pressure Profile Throttling Of A Nitrous Oxide/Hydroxyl-Terminated Polybutadiene Hybrid Rocket Motor, Zachary W. Peterson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Hybrid motors that employ non-toxic, non-explosive components with a liquid oxidizer and a solid hydrocarbon fuel grain have inherently safe operating characteristics. The inherent safety of hybrid rocket motors offers the potential to greatly reduce overall operating costs. Another key advantage of hybrid rocket motors is the potential for in-flight shutdown, restart, and throttle by controlling the pressure drop between the oxidizer tank and the injector. This research designed, developed, and ground tested a closed-loop throttle controller for a hybrid rocket motor using nitrous oxide and hydroxyl-terminated polybutadiene as propellants. The research simultaneously developed closed-loop throttle algorithms and lab scale …

Examination Of Nonpoint Source Nutrient Export From A Snowfall-Dominated Watershed, Lindsey Deboer Carrigan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined nonpoint source pollution via tributaries to Pineview Reservoir. Since few literature values of export coefficients are available for snowfall-dominated watersheds such as Pineview, locally scaled rates were quantified using an upstream-downstream bracketing technique. Nitrogen and phosphorus grab samples were manually collected and discharge measurements were conducted during the annual study period. Additionally, high-frequency monitoring sensors that measured EC, temperature, turbidity, and water level were deployed at the up- and downstream sites to represent short-duration transport events and to examine watershed processes on a more representative time scale.

Daily nutrient loads were estimated from grab samples and flow …

Waste Heat Utilization In An Anaerobic Digestion System, Brett Boissevain

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Anaerobic digestion has great potential as an energy source. Not only does it provide an effective method for waste mitigation, but it has the potential to generate significant quantities of fuel and electricity. In order to ensure efficient digestion and biomass utilization, however, the system must be continuously maintained at elevated temperatures. It is technically feasible to supplement such a system with outside energy, but it is more cost effective to heat the system using only the produced biogas. While there is considerable literature covering the theory of anaerobic digestion, there are very few practical studies to show how heat …

Design Of A Split Hopkinson Bar Apparatus For Use With Fiber Reinforced Composite Materials, Shawn Michael Lang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tabulated material properties are the starting block for the design of most structures. Mechanical structures undergo a wide range of loading conditions. Structures can be loaded statically or dynamically with a wide range of strain rates. With impact loading or high strain rates the relationships between stress and strain are not the same as in static loading. It has been observed that material properties are dependent upon the rate at which they are tested. Many investigators have studied the effect of high compressive strain rate loading conditions, in metals. The most common method for determining the dynamic response of materials …

Value Of Information In Design Of Groundwater Quality Monitoring Network Under Uncertainty, Abdelhaleem I. Khader

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Due to variations in rainfall and limited surface water resources, groundwater is considered the main source for freshwater in many places throughout the word. But this precious resource is being jeopardized by pollution from human activities such as: industry, agriculture, and untreated wastewater, which highlight the need for efficient groundwater resources management. To be efficient, groundwater resources management requires efficient access to reliable information that can be acquired through monitoring. On the other hand, the complicated nature of groundwater aquifers and the uncertainties in the data and the models used to understand the aquifer and its behavior require more powerful …

Multi-Functional Reconfigurable Antenna Development By Multi-Objective Optimization, Xiaoyan Yuan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Antennas are the most essential and significant elements of any wireless communication system. The most common antennas used in wireless communication systems include dipoles/monopoles, horn antennas, loop antennas, and micro-strip antennas. Each type possesses inherent advantages and disadvantages that make them satisfactory for particular applications. The properties of these antennas, however, are fixed by the initial design and cannot be changed. These fixed properties impose restrictions on the overall system performance as the antenna cannot adapt its characteristics in response to the changing propagation parameters of the wireless medium. A reconfigurable antenna, on the other hand, can dynamically change its …

Root Uptake Of Organic Contaminants Into Plants: Species Differences, Naho Orita

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Xenobiotic organic contaminants are widely found in the environment, including soils, sediments, surface waters, wastewater streams, and even in drinking water. Food chain contamination resulting from the uptake of these contaminants by plants is a concern. Although the uptake of a variety of xenobiotic organic contaminants by plants has been reported but the differences between plant species are not fully understood. The emphasis of this thesis research is to further investigate the unique root to shoot transfer ability of “gold rush” zucchini that has been reported repeatedly in recent years.

A pressure chamber technique was used to measure transpiration stream …

New Methods For Engineering Site Characterization Using Reflection And Surface Wave Seismic Surveys, Susit Chaiprakaikeow

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study presents two new seismic testing methods for engineering application, a new shallow seismic reflection method and Time Filtered Analysis of Surface Waves (TFASW). Both methods are described in this dissertation.

The new shallow seismic reflection was developed to measure reflections at a single point using 2-4 receivers, assuming homogeneous, horizontal layering. Two problems commonly encountered in reflection testing are dealt with in this new method. These problems are: phase shifts between the wave source and ground motion; and, loss of high frequency energy. Using approaches to mitigate these problems significantly improved the shape of measured waveforms. However, none …

Numerical And Experimental Study Of Anisotropic Effective Thermal Conductivity Of Particle Beds Under Uniaxial Compression, Jingwen Mo

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Planetary heat flow is of great interests to planetary scientists, which can be used to determine the history and current status of pianetary bodies. Thermal conductivities of planetary bodies are generally measured using long needle-like probes inserted into planet's surface, which measure the horizontal effective thermal conductivity (parallel to the planetary surface). The vertical effective thermal conductivity (perpendicular to the planetary surface), used for heat flow calculation, is assumed to be the same as the horizontal effective thermal conductivity. However, ETC of particle beds is known to be an anisotropic property under low compressive pressures.

The objective of this study …

Improving Complementary Methods To Predict Evapotranspiration For Data Deficit Conditions And Global Applications Under Climate Change, Fathi M. A. Anayah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A reliable estimate of evapotranspiration (ET) in river basins is important for the purpose of water resources planning and management. ET represents a significant portion of rainfall in the water budget; therefore, the uncertainty in estimating ET can lead to the inaccurate prediction of water resources. While remote sensing techniques are available to estimate ET, such methods are expensive and necessary data may not be readily available. Classical methods of estimating ET require detailed land use/cover information that are not readily available in rural river basins. Complementary methods provide simple and reliable approaches to estimate ET using meteorological data only. …

Experimental Studies Of Vertical Mixing In An Open Channel Raceway For Algae Biofuel Production, Ram Sudheer Voleti

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The USU BioEnergy Center has been successful in developing algae feedstocks for renewable biofuels and bioproducts. The concept is to utilize and maximize algae feedstocks for liquid transportation fuels, biomass for burning and digestion, and high value co-products. It is theorized that increasing the mixing in open and closed algal production systems improves the productivity of the algae culture. A raceway cultivation system was chosen to examine the phenomena of mixing. Vertical mixing will provide more uniform exposure to sunlight for all of the algae in the raceway. The main focus of this research was to increase vertical mixing. Delta …

Unified Rating Equations For Cutthroat Flumes Derived From A Three-Dimensional Hydraulic Model, Sathaporn Temeepattanapongsa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A sophisticated mathematical model of three-dimensional hydraulics was used to develop complete calibrations for Cutthroat flumes, which are structures used in canals (or “open channels”) to measure flow rates. Although Cutthroat flumes have been used for many years, and much research has been done on their calibrations and application in the field, never before was there a complete set of calibration parameters for all 24 standard flume sizes. This research was validated by previously published laboratory results on prototype flumes at Utah State University and elsewhere, and it was successful in generating accurate calibration parameters for all 24 flume sizes, …

Aging-Aware Routing Algorithms For Network-On-Chips, Kshitij Bhardwaj

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Network-on-chips (NoCs) are one of the most scalable mediums to interconnect different processors in a multi-processor system. The processors are connected to routers via network interfaces and the routers are connected to each other through links. A routing algorithm is implemented inside each router that decides the path that a packet must take to reach the destination processor from the source. If a path is heavily utilized, the links and routers comprising the path start to age, and therefore can become faulty with time. In order to avoid this situation, the routing logic must be able to distribute the packets …

The Antimycobacterial Activity Of Hypericum Perforatum Herb And The Effects Of Surfactants, Shujie Shen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tuberculosis is a stubborn and lethal infectious disease. The world-wide tuberculosis surveillance reports that the new TB cases ranges from seven to eight million per year and deaths ranges from 1.3 to 1.6 million every year. The treatment of tuberculosis mainly depends on antituberculosis drugs, such as isoniazid, rifampin, pyrazinamide and ethambutol. However, drug-resistance acquisition is an inevitable process during tuberculosis treatment. Today, multi-drug resistant and the extensively drug-resistant TB cases have been widely reported around the world. Thus, the discovery of novel antituberculosis drugs is essential to effective TB treatment. Hypericum perforatum, also called St. John’s Wort, is …

A Study On Conformal Antenna Solutions For Cube Satellites, Maryam Jamali

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This master's thesis presents a study on two types of conformal antennas for the use on cube satellites (CubeSats). The two antenna solutions are including slot and microstrip patch antennas. CubeSats have been one of the most important vehicles for space exploration due to their small sizes and very low payload. At the same time, a challenge rises when allocating extremely limited surface real estate to space instrument, solar cells, and antennas. The most effective solution for such a challenge is to design antennas such that they do not block solar cells or compete for space with solar cells. Accordingly, …

Effects Of Single Panel Replacement Of A Full-Scale, Full-Depth, Precast Concrete Bridge Deck System, Jason Robert Perry

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The use of precast concrete deck panels is becoming increasingly popular for bridge construction and rehabilitation in the state of Utah and across the country. It allows for the use of full depth concrete deck panels but removes the long construction times of traditional cast-in-place methods. One of the challenges to the use of precast deck panels is the transverse deck panel joints that exist between the panels. These joints are unreinforced using traditional methods and therefore are the weakest section of the bridge. In many situations the joint will fail and water seeps through and can damage the bridge …

Compressive Point Cloud Super Resolution, Cody S. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Automatic target recognition (ATR) is the ability for a computer to discriminate between different objects in a scene. ATR is often performed on point cloud data from a sensor known as a Ladar. Increasing the resolution of this point cloud in order to get a more clear view of the object in a scene would be of significant interest in an ATR application.

A technique to increase the resolution of a scene is known as super resolution. This technique requires many low resolution images that can be combined together. In recent years, however, it has become possible to perform super …

Design And Characterization Of Circularly Polarized Cavity-Backed Slot Antennas In An In-House-Constructed Anechoic Chamber, Mangalam Chandak

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Small satellites have become important vehicles for space exploration. One of the challenges on these satellites is their limited surface area, which creates problems in allocating resources for devices such as antennas. Also, an effective satellite communication system often requires circularly polarized antennas. Therefore, integrating cross slot antennas around solar cells to form a multifunctional solar panel is one of the best solutions for small satellites. The cross geometry provides circular polarization and the slot configuration does not compete for any additional surface space. The main goal of this thesis was to design, fabricate, and test such type of slot …

Effective Thermal Conductivity Of Tri-Isotropic (Triso) Fuel Compacts, Charles P. Folsom

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Next Generation Nuclear Plant (NGNP) program objective is to develop a new type of nuclear reactor that produces process heat instead of electricity. The process heat can be used in the production of hydrogen and many other industrial processes. As part of the NGNP program a new type of nuclear fuel is being developed. The fuel is a composite construction of specially coated fuel particles and graphite pressed together in a cylindrical compact.

Thermal conductivity is an important thermophysical property of the fuel that needs to be measured. Knowledge of the thermal conductivity of the fuel will provide accurate …