Engineering Commons^™

Global Evaluation Of Biofuel Potential From Microalgae, Jeffrey W. Moody

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objective of the proposed work is to determine the productivity potential of microalgae around the world based on the current large uncertainty of the productivity
potential found in literature. To achieve this objective, a validated thermal and biological growth model was utilized coupled with weather data files from weather stations around the world. This enabled a realistic assessment of the productivity potential based on actual climatic variables. Sensitivity of microalgae lipid productivity to biomass production, temperature, and variability was performed illustrating the importance of biological and temporal resolution. Results from modeling work were leveraged for a scalability assessment based …

Volatile Organic Compounds (Vocs) In Indoor Air: Emission From Consumer Products And The Use Of Plants For Air Sampling, Todd A. Wetzel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Adults living in North America spend an estimated 80-90% of their time indoors where they can be exposed to a wide range of volatile organic chemicals (VOCs) found in home construction materials and consumer products (e.g. molded plastics, adhesives, cleaning products, paints, etc.). Some of these VOCs are known to be harmful if exposure concentrations are high or occur over a long period of time. Vapor intrusion (VI), the process by which VOCs in the soil or groundwater migrate to indoor air from a contaminated site, can also contaminate indoor air. Since remediation activities to prevent or stop VI are …

Considerations For Hood Placement And Design Downstream From A Fixed-Cone Valve, Barry Jacob Prettyman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In many hydroelectric projects there is a need to safely dissipate the energy associated with the elevation of the water surface. When the flow is not passing through the turbines, bypass valves are often used. A valve that is commonly used is the fixed-cone valve. Fixed-cone valves, also known as Howell-Bunger valves, are devices often used to safely reduce flow energy at dams with medium to high heads. The valve directs the outflow into a conical hollow jet, which requires a large area for energy dissipation. The flow is controlled by an adjustable sleeve, also known as the gate which …

Evaluation Of Composting Of Municipal Solid Waste, J. Ryan Stebbins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Millions of tons of organic waste are lost each year by being deposited in landfills instead of being composted. Composting would increase the life of landfills and reduce the loss of renewable resources. Current composting techniques take approximately 6 months to break down the organic components, such as yard trimmings and food waste. In addition, a large amount of area is required for the windrows piles. Recycling techniques help to separate organics, such as yard trimmings and food waste, from the municipal solid waste (MSW) stream for composting. However, these techniques are time consuming, costly, and not extensively practiced. Since …

Labyrinth Weirs: A Look Into Geometric Variation And Its Effect On Efficiency And Design Method Predictions, Tyler Robert Seamons

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The rehabilitation of dams often requires spillway capacity upgrades. Replacing a less hydraulically efficient linear weir with a labyrinth weir can be an effective way to increase discharge efficiency (discharge at a given upstream head) for a fixed-width channel. Labyrinth weirs are linear weirs folded in plan view to increase total spillway crest length (which in turn increases discharge efficiency within a channel). Labyrinth weirs potentially have limitless geometric configurations. This study was performed to analyze the effects of varying certain geometric parameters on discharge efficiency and design method predictions.

Due to limited cross-sectional flow area near the upstream apex, …

Control Of Grid-Connected Photovoltaic Systems Using Fractional Order Operators, Hadi Malek

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This work presents a new peak seeking strategy for maximum power point operation using fractional order operators in the three-phase grid-connected photovoltaic systems. Moreover, fractional order controllers have been implemented in the voltage and current control loops. The simulation results and theoretical analysis indicate that the proposed fractional order control strategy improves the efficiency of the system by reducing the total harmonic distortion of the injected current to the grid and increases the robustness of the system against uncertainties. Additionally, the proposed maximum power point tracking algorithms provide more robustness and faster convergence speed under environmental variations than other maximum …

An Efficiency-Motivated Attack Against Vehicles In A Platoon: Local Vehicle Control, Platoon Control Strategies, And Drive Train Technologies Considerations, David A. Cornelio Sosa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Automated Electric Transportation Group (AET) at Utah State University proposes to demonstrate the benefits and feasibility of vehicle platooning. A platoon is a transportation system, formed by vehicles that are controlled automatically by computers (the driver does not operate the vehicle while cruising). Platoons are interesting in view of the future because they present many advantages: increase highway capacity and safety, reduce travel time, save energy, and reduce stress for human drivers. There are many problems to solve in order to make vehicle platooning a reality. In this work, the focus is not on making it feasible, but rather …

The Effects Of Pipewall Offsets On Water Meter Accuracy, Jesse M. Pope

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Accurate flow measurement is essential for the management of any type of fluid system. In order for a meter to accurately measure the flow, some installation requirements must be met. These installation requirements are meant to produce a condition where there are limited flow disturbances as the fluid enters the meter. If flow disturbances do occur, the meter may produce inaccurate measurements.

This research investigated the effect on accuracy that different types of 12-inch flow meters have as a result of being installed in pipelines of differing inside diameter. The types of meters chosen for this research were the portable …

Effects Of Froude Scaling On Velocity-Induced Vortices In Physical Models, Michael S. Budge

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Utah Water Research Laboratory at Utah State University proposes to examine further a little known issue frequently seen in research conducted. The Utah Water Research Lab frequently conducts physical model studies of hydraulic structures for organizations around the world during the design process. These studies allow engineers to determine potential design revisions though simulations of operations including flood flows. Often, vortices, or whirlpools, occur in these models. Vortices are common occurrences at intakes in hydraulic structures such as dams and pump sumps. They can be detrimental to the operation and efficiency of these structures.

The purpose of this work …

Spacecraft Guidance Techniques For Maximizing Mission Success, Shane B. Robinson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Traditional spacecraft guidance techniques have the objective of deterministically minimizing fuel consumption. These traditional approaches to guidance are developed independently of the navigation system, and without regard to stochastic effects. This work presents and demonstrates a new approach to guidance design. This new approach seeks to maximize the probability of mission success by minimizing the variance of trajectory dispersions subject to a fuel consumption constraint. The fuel consumption constraint is imposed by formulating the dynamics in terms of a steering command, and placing a constraint on the final time. Stochastic quadratic synthesis is then used to solve for the nominal …

Numerical Examination Of Flux Correction For Solving The Navier-Stokes Equations On Unstructured Meshes, Dalon G. Work

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This work examines the feasibility of a novel high-order numerical method, which has been termed Flux Correction. This is accomplished by comparing it against another high-order method called Flux Reconstruction. These numerical methods are used to solve the Navier-Stokes equations, which govern the motion of fluid flow. High-order numerical methods, or those that demonstrate a third-order and higher solution error convergence rate, are rarely used on unstructured meshes when solving fluid problems. Flux Correction intends to make high-order accuracy available to the larger world of Computational Fluid Dynamics in a simple and effective manner. The advantages and disadvantages of the …

Excimer-Monomer Switching Molecular Beacon: The Study On Synthetic Cryptosporidium Dna Detection, Thermodynamics, And Magnesium Effects, Michael L. Davis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study is to quantify and determine the binding of a molecular DNA probe or molecular beacon used in the detection of a known waterborne pathogen Cryptosporidium parvum. The objectives of this study are to determine the stability, sensitivity, and selectivity of the molecular beacon in detecting synthesized Cryptosporidium DNA sequences. The designed probe is based on a two-fluorophore system that is different than similar molecular beacons that utilize a fluorophore and quencher detection method. A comparative study between the two probes was also performed to demonstrate enhanced selectivity of the fluorophore based molecular beacon. Magnesium …

Uniform Temperature Predictions And Temperature Gradient Effects On I-Girder And Box Girder Concrete Bridges, Edyson Rojas

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Federal Highway Administration (FHWA) created the Long-Term Bridge Performance (LTBP) program with the objective of acquiring quality scientific data for in-service bridge performance throughout the United States. This information will be used to improve the practices of bridge design and maintenance. To accomplish this objective, a variety of sensors were installed on a bridge south of Sacramento, California and a bridge near Perry, Utah. Data from the sensors is constantly gather and analyzed.

This research analyzed the data from the temperature sensors in order to investigate the effect of temperature changes in the California and Utah bridges over a …

Innovative Payloads For Small Unmanned Aerial System-Based Personal Remote Sensing And Applications, Austin M. Jensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Remote sensing enables the acquisition of large amounts of data, over a small period of time, in support of many ecological applications (i.e. precision agriculture, vegetation mapping, etc.) commonly from satellite or manned aircraft platforms. This dissertation focuses on using small unmanned aerial systems (UAS) as a remote sensing platform to collect aerial imagery from commercial-grade cameras and as a platform to track radio-tagged fish. The small, low-cost nature of small UAS enable remotely sensed data to be captured at a lower cost, higher spatial and temporal resolution, and in a more timely manner than conventional platforms. However, these same …

Wsnfs: A Distributed Data Sharing System For In-Network Processing, Joshua C. Kiepert

Boise State University Theses and Dissertations

Wireless sensor networks (WSNs) have emerged as versatile platforms for a wide range of scientific data acquisition applications. Wireless sensor network systems are used in many applications including: surveillance, environmental monitoring, target tracking, wildlife tracking, personal health monitoring, machinery monitoring, and many others. Current research efforts in WSN system designs are moving toward approaches that enable direct in-network processing of acquired sensor data to avoid the high energy costs associated with the bulk transmission of data to outside systems for processing. Implementation of collaborative in-network processing algorithms is a non-trivial issue for WSN system development. Design complexity for in-network processing …

Factors Influencing Water Extractable Phosphorus Reduction In Poultry Litter By Chitosan Treatment, Zachary Paul Simpson

Biological and Agricultural Engineering Undergraduate Honors Theses

Phosphorus is known to be a chief factor in the eutrophication of freshwaters. Phosphorus in land applied poultry litter can runoff and pollute these freshwaters. Chitosan, the deacetylated form of the biopolymer chitin, has been shown to have an effect on reducing water extractable phosphorus (WEP) in poultry litter when applied as a powder. The intent of this study was to measure the effect that acetic acid and incubation time have on chitosan’s ability to reduce WEP in poultry litter. The results were that the presence of poultry litter treatment (PLT) in the litter inhibits chitosan’s ability reduce WEP. Chitosan …

Tapjacking Threats And Mitigation Techniques For Android Applications, Vanessa Cooper

Dissertations, Theses and Capstone Projects (Full IR Collection)

With the increased dependency on web applications through mobile devices, malicious attack techniques have now shifted from traditional web applications running on desktop or laptop (allowing mouse click- based interactions) to mobile applications running on mobile devices (allowing touch-based interactions). Clickjacking is a type of malicious attack originating in web applications, where victims are lured to click on seemingly benign objects in web pages. However, when clicked, unintended actions are performed without the user’s knowledge. In particular, it is shown that users are lured to touch an object of an application triggering unintended actions not actually intended by victims. This …

High-Speed Delta-Sigma Data Converters For Next-Generation Wireless Communication, Sakkarapani Balagopal

Boise State University Theses and Dissertations

In recent years, Continuous-time Delta-Sigma(CT-ΔΣ) analog-to-digital converters (ADCs) have been extensively investigated for their use in wireless receivers to achieve conversion bandwidths greater than 15 MHz and higher resolution of 10 to 14 bits. This dissertation investigates the current state-of-the-art high-speed single-bit and multi-bit Continuous-time Delta-Sigma modulator (CT-ΔΣM) designs and their limitations due to circuit non-idealities in achieving the performance required for next-generation wireless standards. Also, we presented complete architectural and circuit details of a high-speed single-bit and multi-bit CT-ΔΣM operating at a sampling rate of 1.25 GSps and 640 MSps respectively (the highest reported sampling rate in a 0.13 …

Thermodynamics And Reaction Kinetics During Mechanochemical Synthesis And Environmental Testing Of Lanthanide And Actinide Refractory Materials, Gordon Andrew Alanko

Boise State University Theses and Dissertations

High energy ball milling is a broad family of well-known techniques for materials processing that includes mechanochemical synthesis, in which the milled materials react during milling. The latter may involve components reacting in the solid, liquid, or gas phases, and the operative kinetics have hardly been studied. Several manufacturers of high energy ball mills have recently made available instrumented milling vessel lids. These lids are able to monitor the temperature of the lid and the gas pressure within the vessel in situ during milling experiments. This ability is a significant improvement over the ad hoc instrumentation setups sometimes discussed in …

Bio Roll-Up: Self-Assembling Scaffolds For Tissue Engineering, Chase Austyn Brisbois

Nanoscale Science & Engineering (discontinued with class year 2014)

There is an unmet need for controlled, dynamic cell scaffolds that will generate 3-D monolayers of epithelial cells for medical research and tissue engineering. Here we describe a system that uses photoimageable and biocompatible HEMA-based hydrogel bilayers that self-assemble from 2-D substrates into 3-D tube-shaped structures. These structures are patterned on top of another layer that demonstrates an ability to anchor the assembled structure and control the direction and extent of selfassembly. Cell viability was determined by MTT assay which shows material components comparable with the positive control (80-110%). Finally, the masks used in the experiments herein were redesigned to …

Simulation Of Thermal Transit-Time Flow Meter For High Temperature, Corrosive And Irradiation Environment, Elaheh Alidoosti

UNLV Theses, Dissertations, Professional Papers, and Capstones

In the environments of high temperature (300o C - 1000o C), corrosive and even irradiation application, the challenges of providing reliable and accurate flow rate measurement is significant. In comparing with many other existing technologies for normal operation environments, correlated thermal transit-time flow meter show its advantages of resolving the challenges encountered in those harsh conditions. The correlated thermal signals can be detected by two separated thermal sensors (for example, thermocouples) in series alignment along the pipe, and derive the flow rate. It was evaluated to have accurate measurement for small pipe at slow fluid speed. In the higher flow …

Observability In Traffic Modeling: Eulerian And Lagrangian Coordinates, Sergio Contreras

UNLV Theses, Dissertations, Professional Papers, and Capstones

Traditionally, one of the ways traffic flow has been studied is by using the kinematic wave model. This model is studied in the Eulerian framework. Recently, the kinematic wave model has been transformed into Lagrangian coordinates. This model of traffic flow together with the concept of observability for linear time invariant discrete time systems is applied to study the observability of four sections of a freeway in both Eulerian and Lagrangian coordinates. A system with densities in four sections of a freeway is designed, and the observability of the system is studied with different situations for sensors. When the system …

Evaluation Of Conservation Voltage Reduction As A Tool For Demand Side Management, Ali Dorrody

UNLV Theses, Dissertations, Professional Papers, and Capstones

To ensure stability of the power grid, electricity supply and demand must remain in balance in real time. Traditionally utilities, call upon peaking power plants to increase power generation to meet the peak demand during the afternoons of the hot summer months. Demand-side management (DSM), which includes energy efficiency and demand response (DR), works from the other side of the equation - instead of adding more generation to the system, it pays energy users to reduce consumption as it is cheaper and easier to procure than traditional generation. As a consequence, demand-side management allows utility customers to act as a …

Investigating The Physical Properties And Runoff Treatment Capability Of Pervious Concrete Containing Granular Activated Carbon, Mark Elias Elkouz

UNLV Theses, Dissertations, Professional Papers, and Capstones

A current environmental concern is that of urban stormwater runoff, which can carry a multitude of contaminants and could threaten or impair surface waters. Pervious concrete (PC) is a type of concrete with significant void spaces that can facilitate infiltration and lead to less runoff. The EPA cites previous research to show that pervious pavement structures reduce such contaminants as metals and total suspended solids. Since Granular Activated Carbon (GAC) is a well-known contaminant adsorbent, the purpose of this research was to determine if PC with added GAC would result in improved runoff treatment, while still maintaining its material properties. …

Highway Routine Maintenance Cost Estimation For Nevada, Monika Hagood

UNLV Theses, Dissertations, Professional Papers, and Capstones

State highway agencies are obligated to maintain existing roads for the highway systems to work efficiently and with greater longevity. Every year NDOT is responsible for approximately 13,150 lane miles of existing infrastructure. With that in mind, resources need to be provided to maintain the highway system.

The purpose of this research was to estimate annual routine maintenance cost for several typical treatment methods of highways. Five prioritization categories of highways used by NDOT were considered. Linear regression models were developed that present the relationship between costs including total maintenance cost and five maintenance cost components: labor, equipment, materials, manpower …

Modeling Of Short Term And Long Term Impacts Of Freeway Traffic Incidents Using Historical Data, Vidhya Kumaresan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Traffic incidents are major contributors to non-recurring traffic congestion in most urban areas in United States. In addition to losses in terms of injury and property damage, freeway incidents also produce negative effects on the system including increased travel delays, fuel consumption and vehicle emissions. Incident management strategies are aimed at reducing the impacts caused by such incidents. Development of guidelines or models to quantify the impacts of these incidents on the society can aid in analyzing the effectiveness and economic feasibility of such incident management strategies.

The first objective of this study is to calibrate models that relate the …

Progressive Collapse Analysis Of Older Reinforced Concrete Flat Plate Buildings Using Macro Model, Jinrong Liu

UNLV Theses, Dissertations, Professional Papers, and Capstones

Catastrophic progressive collapse of a building can be triggered by a sudden loss of a load-bearing element in an abnormal loading event. There is a large inventory of reinforced concrete flat plate buildings designed in accordance with older codes. Without using shear and integrity reinforcement in slabs, these older flat plates are vulnerable to progressive collapse. The overall goal of this research is to numerically examine the resilience of older flat plate buildings against progressive collapse due to instantaneous removal of an exterior or interior column.

To achieve the research goal, a macro behavioral model of slab-column frame is created …

Weir-Baffled Culvert Hydrodynamics Evaluation For Fish Passage Using Particle Image Velocimetry And Computational Fluid Dynamic Techniques, Mohanad A. Khodier

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Due to a recent increase in environmental awareness regarding fish passage through hydraulic structures, including culverts, an evaluation of passage of wild brown trout through a weir-baffled, prototype-scale culvert, was conducted under a variety of culvert slopes and discharge conditions. The influence of the fish sample population and the lengths of the individual fish on passage rates were investigated. The data showed that the fish sample size of 25 per test was sufficiently large to minimize sample size dependency. Fish behavior, including resting/staging zone locations, while traversing the culvert was observed and reported. Two preferable resting zones for the fish …

Prediction Of Climate Change Effects On Streamflow Regime Important To Stream Ecology, Sulochan Dhungel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Streamflow is expected to change with climate change, but a general understanding of how climate change will affect the characteristics of streamflow important to stream ecosystems is lacking. This thesis focused on specific characteristics of streamflow, or the streamflow regime, that are important to stream ecosystems. The need to evaluate the potential impacts of climate change on stream ecosystems makes it important to study how streamflow regime may change. This work has identified 16 characteristics of daily streamflow time series that quantify the patterns and span the aspects of streamflow regimes important for stream ecosystems. Principal component analysis objectively identified …

The Effects Of Laser Etching On Biocompatability And Mechanical Properties Of Polyetheretherketone, Andrew I. Deceuster

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Polyetheretherketone (PEEK) is a Federal and Drug Administration (FDA) approved biomaterial that has been used as an orthopedic implant material due to its inherent properties. Laser etching has become a popular means to create identification markers on the individual implants as required by the FDA. The interaction of laser energy with polymeric materials could potentially cause changes in the material's biocompatibility and mechanical properties. The objective of this study was to determine the effect of laser energy on the biocompatibility and mechanical properties of implantable PEEK by measuring contact angle, micro-tensile testing, nite-element modeling (FEM), and biocompatibility testing according to …