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Full-Text Articles in Engineering

Minimizing Take Of Threatened Rattlesnakes And Optimizing Project Review In Se Nebraska, Shaun Dunn, Dan Fogell, Colleen Rothe-Groleau Dec 2024

Minimizing Take Of Threatened Rattlesnakes And Optimizing Project Review In Se Nebraska, Shaun Dunn, Dan Fogell, Colleen Rothe-Groleau

Nebraska Department of Transportation: Research Reports

The western massasauga (Sistrurus tergeminus) and the timber rattlesnake (Crotalus horridus) are protected under Nebraska Statute 37-801-811 and listed as threatened species. These species occur in the right-of-way (ROW) along several roads in Jefferson, Gage, Pawnee, and Richardson Counties which necessitates the need for added Environmental Review (ER) from Nebraska Department of Transportation (NDOT) staff and onsite surveys prior and during maintenance and construction to roadways. This project sought to minimize ER time, staff time, and increase the knowledge of these species in southeast Nebraska by:

  1. Identifying precise locations of western massasauga brumation sites;
  2. Mapping travel …


Life-Cycle Cost Analysis Of Fm4 Txdot Roadway Alternatives In Cleburne, Texas, Ethan A. Bright Dec 2024

Life-Cycle Cost Analysis Of Fm4 Txdot Roadway Alternatives In Cleburne, Texas, Ethan A. Bright

2024 Fall Honors Capstone Projects - Archive

The Engineering senior design group proposed a three-span concrete bridge, merged lane intersection, and a single storm conduit system. The Honors contribution to this project was analyzing the design’s alternative’s life-cycle costs to compare the most economic design. The project’s cost consists of initial construction, maintenance, and decommission. Utilizing Texas Department of Transportation (TxDOT) bid code unit prices, each design alternative is calculated by multiplying each material amount by the unit price then summed. Although the parallel conduit system has a cheaper initial cost, it requires more maintenance during its lifetime, therefore the single conduit system was recommended. Notably, cost …


Interpreting Strain Caused By Transient Well Testing, Soheil Roudini Dec 2024

Interpreting Strain Caused By Transient Well Testing, Soheil Roudini

All Dissertations

Understanding reservoir properties and structure is essential to managing subsurface operations, such as geologic storage of CO2 or production of water, hydrocarbons or heat. Previous work demonstrated the potential of analyzing strain data during transient well tests by estimating hydraulic diffusivity using a type-curve-like approach. The following dissertation aims to pursue this potential by developing and evaluating methods for interpreting strain tensor data to improve subsurface characterization. The research advances the classic, intuitive method of using type-curves to interpret well tests, but it also brings together modern computational methods from machine learning, proxy modeling and Bayesian inversion, and it …


Harmonizing Vaccine And Infrastructure Development To Tame Cholera Outbreaks Across Africa, Amira Mohamed Taha, Hussam Mahmoud, Emad M. Hassan, Mohamed M. Ghonaim Dec 2024

Harmonizing Vaccine And Infrastructure Development To Tame Cholera Outbreaks Across Africa, Amira Mohamed Taha, Hussam Mahmoud, Emad M. Hassan, Mohamed M. Ghonaim

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Vaccines and clean water shortages continue to give rise to cholera outbreaks in Africa. Coordinated efforts to increase vaccine distribution and improve physical infrastructure are needed while considering future outbreaks and water demands due to conflicts and climate events.


Performance Of Optimized Composition Of Epoxy Resin Adhesive Used In High Friction Surface Treatment, Jiapeng Li, Xiao Huan, Shubing Wang, Yanping Sheng, Dahui Xu, Zhanping You Dec 2024

Performance Of Optimized Composition Of Epoxy Resin Adhesive Used In High Friction Surface Treatment, Jiapeng Li, Xiao Huan, Shubing Wang, Yanping Sheng, Dahui Xu, Zhanping You

Michigan Tech Publications

The High Friction Surface Treatment (HFST) paving technique is widely employed in engineering practices globally, serving to enhance the long-term anti-skid performance of pavements. However, there still exist significant gaps in research regarding the modified and optimized composition and corresponding content of the polymer binding materials used in HFST, as well as the performance of the pavements laid with modified and optimized blended aggregates during service. To address these issues, this research first modified and optimized the composition ratio of traditional epoxy resin materials. Subsequently, a toughened, high-flow epoxy bonding system suitable for the maintenance of concrete pavements was prepared. …


Thermal Conductivity Characterization Of High Oleic Vegetable Oils Based Hybrid Nanofluids Formulated Using Gnp, Tio2, Mos2, Al2o3 Nanoparticles For Mql Machining, Anthony Chukwujekwu Okafor, Tobechukwu Kingsley Abor, Saidanvar Esanjonovich Valiev, Ignatius Echezona Ekengwu, Abiodun Saka, Monday Uchenna Okoronkwo Dec 2024

Thermal Conductivity Characterization Of High Oleic Vegetable Oils Based Hybrid Nanofluids Formulated Using Gnp, Tio2, Mos2, Al2o3 Nanoparticles For Mql Machining, Anthony Chukwujekwu Okafor, Tobechukwu Kingsley Abor, Saidanvar Esanjonovich Valiev, Ignatius Echezona Ekengwu, Abiodun Saka, Monday Uchenna Okoronkwo

Chemical and Biochemical Engineering Faculty Research & Creative Works

This paper presents the results of thermal conductivity characterization of six high oleic soybean oil (HOSO) and four high oleic canola oil (HOCO)-Based hybrid nanofluids formulated with four types of nanoparticles (Graphene nanoplatelet (xGnP), TiO2, MoS2, and Al2O3) at nanoparticles wt.% concentration from 1 % to 7 % in 1 % increment using the two-step method for use in MQL machining of difficult-to-cut metals. Thermal conductivity of the formulated hybrid nanofluids were measured using Thermtest Transient Hot Wire Liquid Thermal Conductivity Meter at temperatures from 25 °C to 75 °C in increment …


A Strategic Insight Into The Market For Carbon Management Capacity, Mahelet G. Fikru, Ting Shen, Jennifer Brodmann, Hongyan Ma Dec 2024

A Strategic Insight Into The Market For Carbon Management Capacity, Mahelet G. Fikru, Ting Shen, Jennifer Brodmann, Hongyan Ma

Economics Faculty Research & Creative Works

This study presents the market for carbon management capacity via carbon capture, utilization, and storage technologies, identifying demand and supply forces, as well as clarifying the potential impact of market and non-market-based shocks on technology developers versus adopters. The paper addresses a prevailing gap in market analysis, introducing a microeconomic framework and unique dataset to identify key players, market forces, and policy incentives shaping the carbon capture, utilization, and storage landscape. The analysis equips industry stakeholders, policymakers, and investors with valuable insights regarding (1) leaders in the design, development, and manufacture of carbon capture, utilization, and storage technologies (supply), (2) …


Cytotoxicity And Genotoxicity Of Glyphosate And Roundup Quickpro On Chinese Hamster Ovary Cells, Tasnimul Ferdous Dec 2024

Cytotoxicity And Genotoxicity Of Glyphosate And Roundup Quickpro On Chinese Hamster Ovary Cells, Tasnimul Ferdous

Graduate Theses and Dissertations

Glyphosate and Roundup products have become the most used herbicide worldwide. However, previous bans in Europe and recent reversal have caused confusion over their safety. This study aims to investigate the cytotoxic and genotoxic effects of Roundup QuickPro and its main ingredient glyphosate using Chinese hamster ovary (CHO) cells. Cytotoxicity was calculated by measuring CHO cell viability with 72 hours of exposure to each toxicant. Roundup exhibited higher cytotoxicity with LC50 of 511.2 μg/mL than glyphosate’s LC50 of 3389 μg/mL. The recommended application concentration (11,233.7 μg/mL) of Roundup QuickPro is much higher than the measured LC50, which caused complete cell …


Fitting Quality Of Nmr Relaxation Data To Differentiate Asphalt Binders, Rebecca M. Herndon, Kevin Lai, Magdy Abdelrahman, Klaus Woelk Dec 2024

Fitting Quality Of Nmr Relaxation Data To Differentiate Asphalt Binders, Rebecca M. Herndon, Kevin Lai, Magdy Abdelrahman, Klaus Woelk

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Asphalt binder performance grades (PGs) are important metrics in designing pavements for effective transportation infrastructure. the PG system relies on the binder's stiffness and is determined through energy- and time-intensive physical testing. Physical properties, like stiffness, can also be determined by spin–lattice NMR relaxometry, a non-destructive chemical method. NMR relaxometry can quantify the molecular mobility of materials by determining relaxation times from exponential decays of excited nuclear magnetization. While relaxation times have been used to determine physical properties of materials, a quantitative relation to the PG grades of asphalt binder is yet to be established. in this study, T1 NMR …


Assessment Of Pedestrian Safety At Roundabout Slip Lanes: A Study On Design Configurations And Surrogate Safety Measures, Norran Kakama Novat Dec 2024

Assessment Of Pedestrian Safety At Roundabout Slip Lanes: A Study On Design Configurations And Surrogate Safety Measures, Norran Kakama Novat

Masters Theses

The implementation of slip lanes at roundabouts has been widely adopted to improve traffic flow and reduce vehicle conflicts. However, the presence of slip lanes introduces significant risks for pedestrians, influencing vehicle speeds, merging behaviors, and increasing the potential for pedestrian-vehicle conflicts. This study investigates pedestrian safety at roundabouts with various slip lane designs, focusing on their impact on vehicle speeds, pedestrian-vehicle conflicts, and yielding behavior. Also, the study evaluates commonly used surrogate safety measures by employing extreme value models to assess their efficiency.

The study addresses two primary objectives: (1) analyzing the effects of different slip lane configurations on …


Assessing The Critical Factors Influencing Worker Safety In Roadway Work Zones, Bahaa Chammout, Muaz O. Ahmed, Islam El-Adaway Dec 2024

Assessing The Critical Factors Influencing Worker Safety In Roadway Work Zones, Bahaa Chammout, Muaz O. Ahmed, Islam El-Adaway

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Ongoing roadway construction and maintenance activities are essential for sustaining and improving infrastructure. Nonetheless, work zones in the United States continue to experience concerning frequencies of occupational and traffic accidents. Previous research highlighted multiple factors influencing work zone safety, yet their relative impact and importance remain unclear. This study addresses this gap following a multistep methodology. First, 32 safety factors were identified through an extensive literature review in a previous study. Second, a survey was administered among 298 professionals from diverse backgrounds, with an average of 17.75 years of construction experience and 13.78 years of work zone experience, to assess …


Performance Evaluation Of Bio-Oil And High Rubber Content Modified Asphalt: More Effective Waste Utilization, Zihao Ju, Dongdong Ge, Songtao Lv, Dongzhao Jin, Yanhua Xue, Jianping Xian, Wenhui Zhang Dec 2024

Performance Evaluation Of Bio-Oil And High Rubber Content Modified Asphalt: More Effective Waste Utilization, Zihao Ju, Dongdong Ge, Songtao Lv, Dongzhao Jin, Yanhua Xue, Jianping Xian, Wenhui Zhang

Michigan Tech Publications

In this study, the bio-oil was used to reduce the viscosity and preparation temperature of high content of rubber-modified asphalt. The high rubber content modified bio-asphalt (RMBA) was prepared, the rubber and bio-oil contents were 20 %-30 % and 5 %-15 % (mass ratio of neat asphalt), respectively. The viscosity, temperature sweep (TS), frequency sweep (FS), multi-stress creep recovery (MSCR), and bending beam rheometer (BBR) tests were performed to assess the properties of RMBA. The Fourier Transform infrared spectroscopy (FTIR), Fluorescence microscopy (FM), and Scanning electron microscope (SEM) tests were conducted to explore the microscopic morphology of RMBA. Besides, the …


Performance Evaluation Of Surface Treatment Waste Glass As Aggregate In Asphalt Mixture, Miao Yu, Dongzhao Jin, Yu Liu, Zhanping You, Yalong Li Dec 2024

Performance Evaluation Of Surface Treatment Waste Glass As Aggregate In Asphalt Mixture, Miao Yu, Dongzhao Jin, Yu Liu, Zhanping You, Yalong Li

Michigan Tech Publications

Surface modification is a crucial strategy for enhancing the pavement performance of waste glass hot mix asphalt (HMA) mixtures. This study conducts a comparative analysis of various surface modification techniques to pinpoint the key factors that influence the interfacial interaction between waste glass and asphalt. To assess the performance of asphalt mixtures containing surface-treated waste glass, the study employed methods such as Energy Dispersive X-ray Spectroscopy (EDS), boiling water tests, and contact angle measurements, which helped to quantify surface morphology and the effectiveness of different treatments. The evaluation also included assessments of water stability, dynamic stability, small beam bending, and …


Basic Safety Message Generation Through A Video-Based Analytics For Potential Safety Application, Abyad Enan Dec 2024

Basic Safety Message Generation Through A Video-Based Analytics For Potential Safety Application, Abyad Enan

All Theses

With the advancement of modern artificial intelligence techniques, computer vision can play a vital role in enhancing roadway safety by reducing the risk of imminent collisions. To do so, a vision-based safety application is required, where a roadside camera can monitor the roadway traffic and predict potential risks of crashes in real-time. If any risky situation or behavior is observed that may lead to a crash, then a safety application can send warnings to the vehicles at risk. For vision-based safety applications on a roadway section, it is important to accurately monitor each vehicle’s location, speed, acceleration, heading direction, etc. …


Assessing The Potential For Photosynthetic Degradation Of Per- And Polyfluoroalkyl Substances, Marlow Thomas Dec 2024

Assessing The Potential For Photosynthetic Degradation Of Per- And Polyfluoroalkyl Substances, Marlow Thomas

All Theses

PFAS is a prevalent groundwater contaminant. It has been known to cause many health issues for humans and animals including cancer and several diseases. A main problem faced with PFAS is contamination in groundwater. Remediation strategies have been and continue to be researched to try to mitigate this issue. Current treatment strategies to mitigate PFAS include the use of granular activated carbon, ion exchange, chemical oxidation, and many hybrid treatments. There has not been one treatment technology to date that has prevailed as the best due to monetary and time constraints.

The main intention behind this research is to examine …


Comparative Analysis Of Design-Build And Design-Bid-Build Project Delivery Methods Through Cost, Schedule And Quality Performance For Warehousing And Storage Facilities, Vijaya Ravi Prasanth Reddi Dec 2024

Comparative Analysis Of Design-Build And Design-Bid-Build Project Delivery Methods Through Cost, Schedule And Quality Performance For Warehousing And Storage Facilities, Vijaya Ravi Prasanth Reddi

All Theses

Storage facilities are essential for e-commerce operations, providing inventory, distribution, and delivery space. As per the Bureau of Labor Statistics, the number of warehousing and storage businesses in the United States increased from 15,152 in 2010 to 21,287 in 2024, showing continuous growth over the decade. Given the recent surge, there is a need to understand the performance of these facilities better. This study aims to contrast the measure of quantitative performance of design-build (DB) versus traditional design-bid-build (DBB) project delivery methods (PDM) based on cost, schedule, and quality metrics for storage facilities. This research conducted a literature review to …


Field Evaluation Of Transverse Post-Tensioning And Latex Modified Concrete On Bridge Load Distribution, Paige Waters Dec 2024

Field Evaluation Of Transverse Post-Tensioning And Latex Modified Concrete On Bridge Load Distribution, Paige Waters

All Theses

The Airport Road Bridge (ARB) over Rocky Creek in Greenwood, SC is one of 377 channel bridges in South Carolina currently load-posted, limiting vehicle weight and potentially restricting access to vital services. The South Carolina Department of Transportation (SCDOT) seeks a cost-effective method to strengthen these bridges and enhance their load-sharing capacity.

Through live load field testing, this research seeks to use two retrofitting techniques – transverse post-tensioning (PT) and latex modified concrete (LMC) overlay – to determine whether or not channel bridges can be improved. Direct tension testing was also performed to evaluate the substrate-overlay bond of the LMC …


Thermal Conductivity Characterization Of High Oleic Vegetable Oils Based Hybrid Nanofluids Formulated Using Gnp, Tio2, Mos2, Al2o3 Nanoparticles For Mql Machining, Anthony Chukwujekwu Okafor, Tobechukwu Kingsley Abor, Saidanvar Esanjonovich Valiev, Ignatius Echezona Ekengwu, Abiodun Saka, Monday Uchenna Okoronkwo Dec 2024

Thermal Conductivity Characterization Of High Oleic Vegetable Oils Based Hybrid Nanofluids Formulated Using Gnp, Tio2, Mos2, Al2o3 Nanoparticles For Mql Machining, Anthony Chukwujekwu Okafor, Tobechukwu Kingsley Abor, Saidanvar Esanjonovich Valiev, Ignatius Echezona Ekengwu, Abiodun Saka, Monday Uchenna Okoronkwo

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper presents the results of thermal conductivity characterization of six high oleic soybean oil (HOSO) and four high oleic canola oil (HOCO)-based hybrid nanofluids formulated with four types of nanoparticles (Graphene nanoplatelet (xGnP), TiO2, MoS2, and Al2O3) at nanoparticles wt.% concentration from 1 % to 7 % in 1 % increment using the two-step method for use in MQL machining of difficult-to-cut metals. Thermal conductivity of the formulated hybrid nanofluids were measured using Thermtest Transient Hot Wire Liquid Thermal Conductivity Meter at temperatures from 25 °C to 75 °C in increment of 10 °C. Obtained results showed that thermal …


Designing A Robust Lab Scale Electrocoagulation Reactor For Removal Of Micro- And Nanoplastics From Drinking Water, Emmanuel Louis Aduhene Dec 2024

Designing A Robust Lab Scale Electrocoagulation Reactor For Removal Of Micro- And Nanoplastics From Drinking Water, Emmanuel Louis Aduhene

All Graduate Reports and Creative Projects, Fall 2023 to Present

The widespread occurrence of micro and nanoplastics in drinking water sources could cause serious public health issues. These plastics particles, products of industrial operations and weathering of larger plastics, can interact with other contaminants in the environment, leading to more severe environmental pollution. Present drinking water treatment technologies were designed to remove suspended colloids. However, due to the distinct chemical and physical properties of micro and nanoplastics from conventional colloids, it is challenging for traditional chemical coagulation/flocculation/sedimentation process to achieve satisfying removal performance. This report investigates a design of a lab-scale electrocoagulation reactor for the removal of nanoplastics from drinking …


Geotechnical Aspects Of Extraterrestrial Regolith Simulants, Jesus Baca Dec 2024

Geotechnical Aspects Of Extraterrestrial Regolith Simulants, Jesus Baca

Open Access Theses & Dissertations

Geotechnical engineering has been crucial to the success of construction projects on Earth, and now it is time to extend this expertise to other celestial bodies. As NASA planned the Apollo missions, geotechnical engineers conducted extensive studies to understand the properties of lunar soil, using analogs like volcanic ash and other terrestrial materials to simulate the moon's surface. Nevertheless, it was not until the inception of the year 1968 that the Surveyor landers were able to give the first actual estimates of the moon soil geotechnical characteristics such as bearing capacity, void ratio, etc. With the development of more refined …


Sustainable And User-Driven Scope Development Framework For Engineering Design Services Of Transportation Infrastructure Projects, Ahmad Zaki Ghafari Dec 2024

Sustainable And User-Driven Scope Development Framework For Engineering Design Services Of Transportation Infrastructure Projects, Ahmad Zaki Ghafari

All Dissertations

Rapid economic growth has led to a significant increase in transportation demands, exerting unprecedented pressure on infrastructure systems in the United States. State transportation agencies play a vital role in maintaining and developing transportation infrastructure networks within their regions. State transportation agencies face immense pressure from federal and state governments, elected officials, and the public to deliver projects efficiently and within budget. State transportation agencies rely on professional consultants for engineering design services. Engineering design services for transportation infrastructure projects are delayed due to incomplete inaccurate scope. For state Department of Transportation (DOTs), a streamlined scope development process is essential …


Transmission Main Construction Management - An Assessment Of Project Tracking During Transition To A Cloud Based System, Martin C. Munger Dec 2024

Transmission Main Construction Management - An Assessment Of Project Tracking During Transition To A Cloud Based System, Martin C. Munger

LSU New Orleans Theses and Dissertations

A massive $2B settlement between the Federal Government and the City of New Orleans to remediate the damage to municipal infrastructure from Hurricane Katrina and the failed USACE levee system required the repair of roughly 400 of 1600 miles of roadways in New Orleans. The mandated repairs included many subsurface utilities below those roads. Traditional engineering construction project management practices proved inadequate to manage such a massive undertaking on the strict timelines mandated by FEMA funding. Unprecedented volumes of work for the engineering and construction industries and the government agencies tasked with performing the work from design through construction revealed …


Biological Reduction Of Mixed Oxyanions In Wastewater Brine, Katherine J. Earp Dec 2024

Biological Reduction Of Mixed Oxyanions In Wastewater Brine, Katherine J. Earp

UNLV Theses, Dissertations, Professional Papers, and Capstones

Treatment of contaminated brine water is an area of active research spurred by the use of advanced treatment technologies, such as membrane separation, reverse osmosis, ion exchange, etc. for water reuse and recycling, which has become critical due to the impact of climate change on water resources throughout the globe. Biological reduction of harmful organic and inorganic pollutants in water has been demonstrated as an effective method for water and wastewater treatment and would be a potential technology for brine treatment. However, biodegradation of contaminants in high salinity waters is challenging because most microbial communities cannot survive brine environments. The …


Uptake Of Contaminants Of Emerging Concerns (Cecs) By Plants Irrigated With Recycled Waters, Abid Hussain Dec 2024

Uptake Of Contaminants Of Emerging Concerns (Cecs) By Plants Irrigated With Recycled Waters, Abid Hussain

UNLV Theses, Dissertations, Professional Papers, and Capstones

The increasing demand for water in arid and semi-arid regions necessitates the use of recycled water (RW) for irrigation. RW is a viable alternative to conventional irrigation water at most locations, but it can be a major route for contaminants of emerging concerns (CECs) to be taken up by the tissues of food crops, thereby leading to their subsequent entry into the food chain. CECs include pharmaceuticals, personal care products, and industrial chemicals that are generally present at low concentrations in environmental waters, hence their common designation as trace organic compounds (TOrCs), and CECs also include microbiological constituents such as …


Prediction Of Cost And Schedule Changes In Transportation Projects Through Historical Bid And Change Order Document Analysis – Using Oklahoma Dot Project Cases., Rabin Shrestha Dec 2024

Prediction Of Cost And Schedule Changes In Transportation Projects Through Historical Bid And Change Order Document Analysis – Using Oklahoma Dot Project Cases., Rabin Shrestha

UNLV Theses, Dissertations, Professional Papers, and Capstones

Construction bid documents encompass project specifications, drawings, schedules, and other critical details and are the foundation for project bidding and execution. Accurate bid documents are essential to ensure project bids are competitive, realistic, and aligned with requirements. However, bid documents are susceptible to risks from various sources. Failure to identify and rectify these risks can result in inaccurate cost estimates and higher bids. Therefore, identifying and resolving risks within bidding or contract documents are of utmost importance. While prior research has shed light on potential risk factors within the bid documents, a noticeable gap remains in the literature regarding identifying …


A Mass Balance Model Of The Great Salt Lake, Ut With Adaptive Management Applications, Diana Dunn Dec 2024

A Mass Balance Model Of The Great Salt Lake, Ut With Adaptive Management Applications, Diana Dunn

All Graduate Theses and Dissertations, Fall 2023 to Present

The Great Salt, Utah, USA is a saline lake that provides critical habitat for ecologic communities and generates $1.3 billion annually. It has gone through detrimental change since the 20th century. Streamflow reaching the lake has been decreased by upstream withdrawal for industrial and municipal use, causing the lake level to drop and salinity to increase to unhealthy levels. Further, in 1959, it was segregated into north and south sections by a railroad causeway. Due to the causeway and limited exchange of water through two bridges, the lake sections have significantly different water surface elevation and salinity levels. The …


Channel Dynamics In Response To Compounding Hydrogeomorphic Disturbances In A Steep Burned Watershed, Paxton Ridgway Dec 2024

Channel Dynamics In Response To Compounding Hydrogeomorphic Disturbances In A Steep Burned Watershed, Paxton Ridgway

All Graduate Theses and Dissertations, Fall 2023 to Present

Wildfires significantly increase sediment input to rivers through various pathways, including post-fire debris flows. Understanding how mountain rivers respond to these sediment inputs is crucial for predicting and managing downstream impacts on infrastructure, water security, and aquatic habitats. While the causes and characteristics of post-fire debris flows have been extensively studied, the morphological changes in downstream fluvial channels remain poorly understood. This study uses scripted spatial analysis toolsets, high-resolution pre- and post-fire DEMs, repeat cross-sectional surveys, time-lapse footage, and pebble counts to document channel responses to sediment supply in a burned steep mountain stream in the upper Colorado River Basin, …


Barriers And Drivers To Bus Electrification: The Transit Agency's Perspective, Aleks C. Paskett Dec 2024

Barriers And Drivers To Bus Electrification: The Transit Agency's Perspective, Aleks C. Paskett

All Graduate Theses and Dissertations, Fall 2023 to Present

Battery-electric buses (BEBs) have become increasingly common in recent years, as transit agencies around the world seek to reduce their carbon emissions. Although many agencies and governments have set ambitious climate goals pushing for increased adoption of BEBs, some agencies face difficulty transitioning their fleets to this technology. This study seeks to understand the challenges faced by these agencies, as well as their motivations for adopting BEBs. Researchers conducted a series of interviewers with twelve transit leaders representing ten transit agencies who were leading BEB adoption programs, asking questions about their experiences trying to implement this technology. The interviewees stated …


Assessing Canopy Features, Its Shading Factor, And Their Influence In The Estimation Of Evapotranspiration In Almond Orchards Using Uas Information And The Two-Source Energy Balance Model, Moises R. Duran-Gomez Dec 2024

Assessing Canopy Features, Its Shading Factor, And Their Influence In The Estimation Of Evapotranspiration In Almond Orchards Using Uas Information And The Two-Source Energy Balance Model, Moises R. Duran-Gomez

All Graduate Theses and Dissertations, Fall 2023 to Present

This study explored how canopy biomass and shadows affect evapotranspiration (ET) estimates, a crucial factor for irrigation management in almond orchards in California’s Central Valley. Data from 24 drone flights over three almond plots in 2021 and 2022 were analyzed using the Two-Source Energy Balance (TSEB) model, combined with meteorological data from EC-towers. The study found that filtering out shadows improved ET estimation, particularly in young orchards, and identified the importance of using new Leaf Area Index (LAI) models for better accuracy. This research is part of the T-REX initiative, which integrates drone and ground-based data to enhance water use …


Examining The Impacts Of Demographics, Individual Experiences, And Perceptions On Range Anxiety And Electric Vehicle Road Trips, Joshua Ward Dec 2024

Examining The Impacts Of Demographics, Individual Experiences, And Perceptions On Range Anxiety And Electric Vehicle Road Trips, Joshua Ward

All Graduate Theses and Dissertations, Fall 2023 to Present

Range anxiety is perhaps the most widely cited barrier to electric vehicle (EV) adoption and use. Range anxiety is generally defined as a general fear that an EV has insufficient battery range or that there is insufficient charging infrastructure to travel from one place to another. Although this barrier is widely cited, there is little research that investigates how EV drivers experience range anxiety and how it might vary based on personal characteristics, perceptions, and experiences. Data on long-distance EV trips is also scarce in the United States and mainly limited to personal stories of an EV road trip.

This …