Engineering Commons^™

Faults Segmentation In Levee Systems Using Deep Learning Approaches, Manisha Panta

LSU New Orleans Theses and Dissertations

Levees are earthen structures constructed to mitigate flooding in low-lying areas. Although levee systems can reduce flood risks, they cannot completely eliminate them. Failures within flood control systems due to inadequate maintenance or strong water currents can lead to significant property damage and catastrophic loss of life, as was seen during Hurricane Katrina. Consequently, regular inspections are essential to identify and address any issues with the levees promptly. However, current inspection methods rely on manual techniques that are time-consuming, labor-intensive, and prone to human error. Therefore, this study proposes using deep learning models for more efficient and frequent assessment of …

Development Of Pre-Magnetized Magnetorheological Elastomer For Bidirectionally Variable Stiffness Applications, Choonghan Lee

UNLV Theses, Dissertations, Professional Papers, and Capstones

Magnetorheological elastomers (MREs) utilize magnetic forces between ferromagnetic particles to cause variable stiffness properties and damping with external magnetic fields. In the MREs, the particles are embedded in a cured elastomer matrix, and an external magnetic field makes the stiffness change due to induced magnetic forces among particles. A disadvantage of the conventional MREs is that they cannot be softened (reduced stiffness) under an external magnetic field. Considering that there are many engineering applications where fast changes of stiffness in both directions (stiffening and softening) are required, embedding magnetically biased particles in the MRE can provide potential solutions. In this …

An Avalanche Transistor-Based Pulse Generator Design For Infrared Laser Applications, Abraham Lopez

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis details the design and results of a circuit intended for infrared laser applications, specifically for transcranial infrared light simulation (TILS) experiments and for use as a range finder. The circuit itself is comprised of a transistor, high voltage power supply, laser diode, capacitor, resistor, diode, and low voltage pulse. The design of a range finder is also developed. The range finder design is the same as the circuit developed for TILs with the addition of a few more components for receiving the returned light pulse such as a photodiode, op-amp, and comparator. The techniques used for a successful …

Towards Cfd Investigations Into Particulate Air Pollution Of A Desert Urban Environment, Prosun Roy

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation has explored computational fluid dynamics (CFD) techniques for studying particulate air quality in the Las Vegas urban area. The dissertation is based on three research tasks:

• • High time-resolution fenceline air quality sensing and dispersion modeling for environmental justice-centered source attribution. (Chapter 2)
• • Pollen dispersion and deposition in real-world urban settings: A computational fluid dynamic study. (Chapter 3)
• • Effects of urban canopy parameterizations on modeling pollen dispersion and exposure. (Chapter 4)

In Chapter 2, we investigate the facilitation of low-cost air quality sensors (LCAQS) and CFD technique on exposure assessment of environmental justice (EJ) communities and …

Poly(Alkyl Aldehyde)S: A New Class Of Closed-Loop Recyclable Plastics, Kyle Arnold Nogales

Boise State University Theses and Dissertations

This dissertation will describe a new class of closed-loop recyclable, self-immolative polymers that undergo selective, complete, and rapid depolymerization in the solid state when triggered. Self-immolative poly(alkyl aldehyde)s are synthesized efficiently in approximately 60% yield using anionic polymerization, which provides access to polymers in accessible lengths ranging from short (M_n value of 2 kDa) to long polymers (M_n value of 5,000 kDa). The physical and thermal properties of the polymers can be tuned rationally by appropriate choice of the aldehyde monomer, with some of the polymers displaying mechanical properties that are similar to traditional plastics. The polymers depolymerize …

Analysis Of Emerging Constituents In An Activated Sludge Treatment Facility, Abigail Mae Sigurdson Ryan

Boise State University Theses and Dissertations

Emerging constituents (ECs), or contaminants of emerging concern (CECs), are pharmaceuticals and personal care products (Contaminants of Emerging Concern including Pharmaceuticals and Personal Care Products | US EPA, 2023). The primary source of ECs in surface waters is the discharge from wastewater treatment facilities (WWTF) (Kumar et al., 2022). Little is known about the effects treatment processes have on ECs. Research regarding ECs has increased due to the threats they pose to the environment and human health (Khan et al., 2021). This research aimed to expand understanding ECs’ fate through an activated sludge WWTF. This was accomplished by studying concentrations …

Robust Control Of Contact-Rich Robots Via Neural Bayesian Inference, Nardos Ayele Ashenafi

Boise State University Theses and Dissertations

We provide several data-driven control design frameworks for contact-rich robotic systems. These systems exhibit continuous state flows and discrete state transitions, which are governed by distinct equations of motion. Hence, it is difficult to design a single policy that can control the system in all modes. Typically, hybrid systems are controlled by multi-modal policies, each manually triggered based on observed states. However, as the number of potential contacts increase, the number of policies can grow exponentially and the control-switching scheme becomes too complicated to parameterize. To address this issue, we design contact-aware data-driven controllers given by deep-net mixture of experts. …

Hydraulic Conductivity's Impact On Rise Of Excess Pore-Water Pressure During Seismic-Induced Liquefaction, Holly Gunderson

Boise State University Theses and Dissertations

Liquefaction is a geohazard causing loss of lives and infrastructure around the world. During earthquakes the shaking of the ground may cause a loss of soil strength that results in the settlement of buildings, landslides, failure of earth dams, amongst other hazards (Liquefaction of Soils During Earthquakes, 1985). Liquefaction is the result of a sudden increase in the pore-water pressure (PWP)— referred to as excess pore-water pressure (EPWP)— in loose, saturated, noncohesive, fine soils during seismic shaking. Due to the small pores and low hydraulic conductivity of these soils, the shaking-induced EPWP has less time to dissipate, leading to the …

Photophysical Studies Of Electronic Structure And Excited-State Dynamics Of Dna-Templated Cyanine Dye Aggregates, Jonathan Samuel Huff

Boise State University Theses and Dissertations

The invention and widespread adoption of the digital computer in the last century has led to an era of rapid technological advancement that has continued to the present day. This advancement has been sustained to a large degree by continued miniaturization of the electronic components in microprocessors, which results in increased computing power and energy efficiency. In recent years, this strategy has produced diminishing returns because the cost for each incremental size reduction increases as engineers approach the fundamental scaling limits of silicon-based semiconductor devices. Meanwhile, breakthroughs in DNA nanotechnology hold great promise for a new generation of self-assembled nanodevices …

Investigating The Causes Of A Landslide In Terra Nativa Subdivision And Designing Slope Stabilization Using Recycled Plastic Pins, Clara Klamm

Boise State University Theses and Dissertations

In early 2016, five homes along Alto Via Court in the Terra Nativa Subdivision of the Boise Foothills began to move. By May of 2016, the street was closed due to safety concerns, and a few years later, the homes were demolished. Despite the heartbreak and legal action that followed the event, a definitive cause of the landslide was never identified. To date, the site remains vacant. This research aims to investigate the potential causes of the slide to help identify the contributing factors that resulted in the mishap. In addition, the research seeks to design a way to stabilize …

Transformation Pathways Of Lanthanide-Free Mn-Al-Ga-X Alloys Where X = Co, Fe, And Ni, Shane L. Palmer

Boise State University Theses and Dissertations

Ubiquitous rare-earth, (i.e. lanthanide) permanent magnets (PMs) composed of Nd-Fe-B are the strongest PMs on the market. However, limited mineral sources, complex elemental separation, and supply chain volatility have shifted the lanthanides to critical material status. Inexpensive, readily available materials are sought to fill an energy product performance gap to reduce dependency on lanthanide PMs. Frequently, lanthanide PMs are used in applications where their energy products are excessively high. Mn-Al based permanent magnets offer a potential substitute for PM applications which do not require the high energy product of a lanthanide PM. MnAl alloys form a metastable ferromagnetic tetragonal …

An Accelerated Corrosion Test Method For Pre-Cracked Reinforced Concrete, Shahriar Abed

Civil Engineering Dissertations - Archive

Reinforced concrete (RC), a composite material combining the strength of concrete and the tensile strength of steel reinforcement, has significantly transformed the field of civil engineering and contributed to the advancement of modern infrastructure. Reinforced concrete structures are susceptible to deterioration over time despite their numerous advantages. One of the primary factors leading to the degradation of RC is the corrosion of steel reinforcement, primarily caused by exposure to aggressive environmental elements such as chloride ions, carbonation, and moisture. This dissertation aims to provide valuable insights into the accelerated corrosion behavior of steel bars embedded in concrete, considering factors such …

Exploring Spatial Associations And Complex Interactions Between Geotechnical Properties And Electrical Resistivity Values In Clayey Soils, Mina Zamanian

Civil Engineering Dissertations - Archive

ABSTRACT: A successful design and construction of infrastructure systems such as highways and bridges highly depend on accurate estimation of geotechnical properties and understanding their spatial distributions, especially in reliability-based designs such as the load and resistance factor design (LRFD) method. Insufficient and inaccurate subsurface information has a major contribution to cost overruns and delays in up to 50% of all infrastructure projects. Insufficient site investigation may also contribute to inadequate or conservative designs, leading to costly failures or increased project costs. Hence, geophysical methods, such as electrical resistivity imaging, that can potentially transform the existing subsurface investigations are used …

Study Of Dry Mixing Method To Apply Microbial-Induced Calcite Precipitation For Soil Treatment, Ruchi Shrestha

Boise State University Theses and Dissertations

Microbially Induced Calcite Precipitation (MICP) has emerged as a promising technique for soil stabilization, traditionally involving the preparation and mixing of treatment solutions with the soil. However, this thesis explores a novel approach of applying MICP by directly mixing dry chemical compounds into the soil and subsequently adding water. This alternative method offers potential advantages in terms of convenience, ease of implementation, and cost savings.

The objective of this research is to investigate the applicability of dry mixing protocols for MICP in soil stabilization. Through comprehensive experimentation, three different dry protocols were developed and applied to five different soils. The …

Dynamic Response Of Cohesive-Frictional Soils Under Thermo-Controlled Constant Water Content Cyclic Simple Shear Testing, Daniel Robert Green

Civil Engineering Dissertations - Archive

Dynamic Response of Cohesive-Frictional Soils Under Thermo-Controlled Constant Water Content Cyclic Simple Shear Testing Daniel R. C. Green The University of Texas at Arlington, 2023 Supervising Professor: Dr. Laureano R. Hoyos A considerable portion of the emerging geothermal infrastructure in the country is located in earthquake prone areas while being supported and/or surrounded by soil deposits located well above the groundwater table. Geotechnical earthquake research in the country, however, continues to be mostly focused on soil response under saturated conditions, especially soil liquefaction phenomena, while most of the work on dynamic response of compacted soils has not taken thermal conditioning …

Cement-Based Nanocomposites With Tunable Electrical And Thermal Conductivity, Myrsini Maglogianni

Civil Engineering Dissertations - Archive

ABSTRACT: While concrete, the most widely used construction material exhibits low electrical and thermal conductivity, it can be engineered at the nanoscale to exhibit energy-related functionalities. This dissertation aims to develop nanoengineered cementitious composites with high electrical conductivity and tunable thermal conductivity to enable energy-related functionalities such as electricity generation and thermal heating capabilities. Highly dispersed nanostructured materials with different intrinsic properties were used to modify the thermal and electrical properties of the developed cementitious composites to enable their thermoelectric (TE) and/or electrothermal (ET) characteristics. One of the objectives of this research was to optimize the electrical-to-thermal energy conversion capability …

Investigation On The Impacts Of Land Subsidence And Urbanization On Flood Inundation In Texas, Han Jiang

Civil Engineering Dissertations - Archive

Floods, being a prevalent and catastrophic natural hazard, have resulted in enormous losses to human lives and properties all over the world. Hence, there is a pressing need to enhance urban resilience and to improve emergency response capacities in order to mitigate the risks posed by flood hazards. Many models have been developed by engineers to simulate and examine the hydrologic and hydraulic responses to the changes within the physical environment. However, there are still knowledge gaps in advancing the understanding of the H&H behavior and hydrodynamics modeling performance. This doctoral study aims to help bridge such gaps via assessing …

An Integrated Algorithm For Automatic Gpr Data Processing For Concrete Rebar Location, Lihong Mao

Civil Engineering Dissertations - Archive

ABSTRACT: Ground Penetrating Radar (GPR) has emerged as a valuable nondestructive testing technique for subsurface imaging and characterization in civil engineering applications. In particular, GPR plays a crucial role in the evaluation of reinforced concrete (RC) structures, enabling the determination of concrete cover thickness and the localization of reinforcement. However, the effectiveness of GPR data analysis is often hindered by inherent challenges, such as unknown time-zero, strong noise, and blurred signals, making the accurate and simultaneous determination of rebar horizontal location and depth a challenging task. This Ph.D. research aims to address these challenges and enhance the accuracy and efficiency …

Digital Twin Enabled Winter Operations Management Through The Integration Of Artificial Intelligence, Sensory Level Data, And Publicly Available Data, Pooya Darghiasi

Civil Engineering Dissertations - Archive

Monitoring real-time information on road conditions, especially during winter storms, is crucial to establishing winter maintenance strategies by the State Departments of Transportation (State DOTs) in the United States. States and local highway agencies allocate substantial resources each year for winter operations to improve road safety during winter storms. However, most weather-related vehicle accidents happen on snowy, slushy, or icy surfaces, leading to a significant number of fatalities and injuries annually. Traditionally, transportation agencies rely on the information provided by Road Weather Information Systems for monitoring road conditions along roadways. However, these systems are costly and only provide estimates at …

Towards Sustainable Additive Manufacturing: Assessment Of Cost, Greenhouse Gas Emission, And Recyclability, Lei Di

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Additive Manufacturing technologies fabricate 3D objects layer by layer following a predesigned CAD model. Owing to the unique layer-wise production method, additive manufacturing offers competitive advantages in comparison with traditional subtractive manufacturing, such as shortened production time, increased design freedom, improved manufacturing capability and complexity, and reduced manufacturing waste. Numerous research studies have been conducted to design, understand, and improve additive manufacturing technologies in order to facilitate the implementation in the supply chain. On the other hand, with the rapid growth of additive manufacturing, sustainability issues that exist on both process level and supply chain level have started to receive …

Development & Validation Of Needle-Based Metrics For Hemodialysis Cannulation Skill Assessment, Ziyang Zhang

All Dissertations

Dialysis is a vital medical treatment for patients with end-stage renal disease. An arteriovenous fistula, a surgically created connection between an artery and a vein, is the preferred vascular access for dialysis due to superior clinical outcomes. However, cannulation complications caused by needle-related errors are common and dangerous, necessitating the need for effective cannulation training. Despite cannulation being a challenging and complex clinical procedure, little is known about the quantitative aspects of needle insertion dynamics necessary for skilled cannulation. The aim of this study was to develop meaningful and instructive needle-based metrics for cannulation skill assessment and training.

Two iterations …

Co-Simulation Of Active Magnetic Bearing Rotors Using Adams, Msc Apex, And Simulink, Shea A. Charkowsky

Master's Theses

Apex-Adams-Simulink co-simulation is applied to active magnetic bearing (AMB) rotors, demonstrating results unshown in literature, including continuous frequency response, and unavailable in known rotor dynamics software, including touchdown bearing impact. AMBs levitate rotors without contact, so they involve no friction, wear, lubrication, pollution, or shaft speed limits and are thus valuable for large, high-speed applications. Modeling of such rotors, necessary for safety and performance, simultaneously requires flexible body dynamics and advanced control design, but simulation programs tend to specialize in only one or the other. The co-simulation method combines multiple such programs—MSC Apex (finite element modeling), Adams (multibody dynamics), and …

Phase Distribution Of Nickel, Chromium, And Cobalt In Seawater At Olivine-Enriched Beaches: Implications For Carbon Capture By Enhanced Silicate Weathering, Nathaniel J. Padrnos

Master's Theses

The application of olivine to coastal areas is a proposed method of removing carbon dioxide from the atmosphere for climate change mitigation. Olivine is abundant and dissolves relatively fast, but it contains trace amounts of nickel (Ni), chromium (Cr), and cobalt (Co) which may be toxic to marine biota in cases of widespread coastal olivine spreading. Prior studies have suggested that Ni concentrations in marine sediments and/or the overlying water column due to olivine dissolution could be a limiting factor for its carbon capture potential. Therefore, it is critical to understand and model the processes affecting trace metal bioavailability after …

Generative Neural Network-Based Defense Methods Against Cyberattacks For Connected And Autonomous Vehicles, M Sabbir Salek

All Dissertations

The rapid advancement of communication and artificial intelligence technologies is propelling the development of connected and autonomous vehicles (CAVs), revolutionizing the transportation landscape. However, increased connectivity and automation also present heightened potential for cyber threats. Recently, the emergence of generative neural networks (NNs) has unveiled a myriad of opportunities for complementing CAV applications, including generative NN-based cybersecurity measures to protect the CAVs in a transportation cyber-physical system (TCPS) from known and unknown cyberattacks. The goal of this dissertation is to explore the utility of the generative NNs for devising cyberattack detection and mitigation strategies for CAVs. To this end, the …

A Mixed Methods Analysis Of Influences Surrounding Undergraduate Science Recruitment: Identifying Challenges And Opportunities, Evelyn Abagayle Boyd

All Dissertations

Often prevalent in the sciences, undergraduate research experiences (UREs) are highly beneficial engaged learning experiences in higher education. Though the benefits of UREs are well established, there is little information about which students participate in these experiences and the pathways they take to become engaged in them. This study consists of three works which surround the overarching research question: How do undergraduate science students initialize research experiences such that departments and institutions can improve access to these high-impact practices? Utilizing the intersection of the theories of Science Capital and Social Cognitive Career Theory, this study provides insight and recommendations into …

Experimental Study Of Linux Flightsize Estimation, Mingrui Zhang

School of Computing: Dissertations, Theses, and Student Research

Transmission Control Protocol (TCP) is a fundamental Internet protocol responsible for controlling and coordinating the Internet traffic. As a result, TCP significantly influences the overall performance and stability of the Internet. One critical information required by a TCP connection to make decisions is FlightSize, which is the total amount of outstanding data contributed by the connection to the Internet. The FlightSize information is used by a TCP connection to determine its future sending rate and also avoid traffic congestion and collapse in the Internet. Consequently, an inaccurate estimation of FlightSize can result in degraded performance and instability of the Internet. …

Adaptation Of Nirtrifiers And Heterotrophs To Low Dissolved Oxygen In An Activated Sludge Biological Nutrient Removal Pilot Plant, Shashank Khatiwada

Civil & Environmental Engineering Theses & Dissertations

Low dissolved oxygen (DO) operation is one of the innovative technologies in biological nutrient removal (BNR) processes that is being investigated due to the potential to reduce aeration requirements, reduce a treatment plant’s carbon footprint, and to lower costs associated with chemical addition to promote denitrification. These benefits are achieved through development of micro-zones, within aerated basins where simultaneous nitrification and denitrification (SND) can occur. In this study, an activated sludge BNR pilot was run in an anerobic/aerobic (A/O) configuration at a controlled temperature and constant flow to observe microorganism-driven transformations of nitrogen and phosphorus at varying low DO conditions. …

Chemical And Physical Interaction Mechanisms And Multifunctional Properties Of Plant Based Graphene In Carbon Fiber Epoxy Composites, Daniel W. Mulqueen

Mechanical & Aerospace Engineering Theses & Dissertations

Graphene has generated substantial interest as a filler due to its exceptional strength, flexibility, and conductivity but faces obstacles in supply and implementation. A renewable, plant-based graphene nanoparticle (pGNP) presents a more accessible and sustainable filler with the same properties as mineral graphenes. In this study, the mechanisms of graphene reinforcement in carbon fiber reinforced plastic (CFRP) were examined, along with the resulting improvements to mechanical strength, resistance to crack propagation, electrical and thermal conductivity at elevated temperatures. pGNP, produced from renewable biomass, was shown to have a graphitic structure with flakes 3-10 layers thick and a median lateral size …

A Comparative Study Of Vinti-Based Orbit Propagation And Estimation For Cubesats In Very Low Earth Orbits, Ethan Michael Senecal

Mechanical & Aerospace Engineering Theses & Dissertations

In recent years, there has been a growing interest in CubeSats and very low Earth orbit (VLEO) space missions. Mission SeaLion, a collaborative CubeSat mission between Old Dominion University, the U.S. Coast Guard Academy, and U.S. Air Force Institute of Technology, planned to launch a 3U CubeSat into VLEO. The VLEO mission is a particularly challenging environment for navigation and orbit propagation because drag introduces a significant perturbation for orbit models such as SGP4. Additionally, mission requirements left no capacity for attitude determination or control, further reducing knowledge of drag behavior of the satellite in flight. This deficiency is a …

Evaluating Direct Filtration As An Alternative To Conventional Carbon-Based Advanced Treatment For Indirect Potable Reuse, Savannah M. Flemmer

Civil & Environmental Engineering Theses & Dissertations

Hampton Roads Sanitation District (HRSD) is recharging purified wastewater into the Potomac Aquifer via the Sustainable Water Initiative for Tomorrow (SWIFT) project. Conventional SWIFT treatment applies coagulation, flocculation, sedimentation, ozonation, biofiltration, granular activated carbon (GAC) adsorption, and ultraviolet disinfection to secondary effluent to produce water that meets drinking water standards for managed aquifer recharge. HRSD is considering implementing direct filtration as an alternative to conventional treatment for two additional SWIFT facilities. Direct filtration presents an opportunity for significant cost savings by eliminating sedimentation, shortening flocculation detention time, and reducing coagulant usage. Without upstream removal of solids and organics, however, biofilters …