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Denoising Diffusion Probabilistic Models Based Accelerated Mri, Alexander Francis Bugielski May 2024

Denoising Diffusion Probabilistic Models Based Accelerated Mri, Alexander Francis Bugielski

Theses and Dissertations

Magnetic Resonance Imaging (MRI) is a cornerstone in obtaining intricate visualizations of anatomy and physiological processes within the human body. However, its extensive scan duration not only causes patient discomfort but also increases the likelihood of motion-induced artifacts in the images. To address such a challenge, this study investigates deep neural network models for reconstructing high-resolution MRI images from noisy and significantly undersampled data in a supervised learning manner. Specifically, it compares three models: a conventional U-Net, a self-attentive U-Net, and an innovative probabilistic diffusion model that builds upon the self-attentive U-Net architecture. These models are evaluated on their ability …


Geometric Multi-Resolution Analysis Across Signals, Images, And Networks, Felicia Schenkelberg May 2024

Geometric Multi-Resolution Analysis Across Signals, Images, And Networks, Felicia Schenkelberg

Dartmouth College Master’s Theses

This research delves into the transformative potential of Geometric Multi-Resolution Analysis (GMRA) as a robust tool for dimensionality reduction and data analysis in the context of high-dimensional graphs. Statistical techniques for classification have historically been tailored for scenarios wherein the number of observations significantly exceeds the number of features, a paradigm characteristic of low-dimensional datasets. However, recent advancements in technologies have ushered in a transformative era in data collection practices across diverse domains, resulting in the acquisition of extensive feature measurements. As a result of this shift, datasets have transitioned into a high-dimensional realm wherein the number of features significantly …


Advancing Near Surface Soil Moisture Measurements Using Robotics, Automation, And Remote Sensing, Hemanth Narayan Dakshinamurthy May 2024

Advancing Near Surface Soil Moisture Measurements Using Robotics, Automation, And Remote Sensing, Hemanth Narayan Dakshinamurthy

All Graduate Theses and Dissertations, Fall 2023 to Present

Near-surface soil moisture, or the water content within the soil, is important for understanding the interactions between land and the atmosphere, and for monitoring plants in agricultural settings. However, soil moisture can be highly variable within the same field and varies considerably with time. The challenge involved with measuring soil moisture is that traditional techniques that rely on obtaining large samples are labor and time-intensive, especially for large fields. Developments in sensor technologies have allowed users to record the soil moisture regularly at the points where the sensors are installed. However, to understand how soil moisture changes across a field …


Routing Opportunities For Commercial Crossings Between El Paso And Juarez, Marek Musil May 2024

Routing Opportunities For Commercial Crossings Between El Paso And Juarez, Marek Musil

Open Access Theses & Dissertations

This thesis explores the topic of commercial movements between the El Paso and Ciudad Juarez road networks and the implications of the possible changes in their routing. This area houses several ports of entry, which present one of the busiest commercial and personal border crossings in the whole nation. The primary focus was to evaluate the recently proposed reconstruction scenario of removing trucks from the Bridge of the Americas and study the impacts on the flows throughout the other ports. The chosen tool to support the analysis is a mesoscopic simulation software called DynusT, which is capable of modeling the …


Smart Public Transportation And Mobility Hub Design In El Paso, Jiri Vojtisek May 2024

Smart Public Transportation And Mobility Hub Design In El Paso, Jiri Vojtisek

Open Access Theses & Dissertations

This thesis explores the potential of a Smart Public Transportation concept and mobility hub design as tools to mitigate the growing trend of transportation issues, such as traffic congestion, reliance on privately owned vehicles, or unattractive public transportation. Consequently, residentsâ?? lives are negatively affected by excessive noise, air pollution, and travel delays, leading to increased safety risks, lost productivity, and a lower quality of life. Considering these challenges, the study begins by analyzing the current state of public transportation in El Paso. Next, it introduces a toolkit from the Smart City concept, followed by case studies of best practices of …


Does California High-Speed Rail Promote Accessibility For Station Cities?: Case Study Of Fresno And Merced, Chih-Hao Wang, Na Chen May 2024

Does California High-Speed Rail Promote Accessibility For Station Cities?: Case Study Of Fresno And Merced, Chih-Hao Wang, Na Chen

Mineta Transportation Institute

California High-Speed Rail (CHSR) will largely change transportation cost across the state after it starts operating. Past studies show that only Fresno and Merced among station cities in the Central Valley would attract more future activities with the CHSR. The establishment of active CHSR also implies a new daily living sphere for all the station cities, and, therefore, accessibility to work and residential amenities should be reviewed to inform planners of future land-use and transportation developments. A research framework has been developed better to understand the impact of CHSR on job and amenity accessibility by driving, transit, and walking in …


Designed For Life: Unearthing Just And Sustainable Urban Design Through The Daylighting Of Phalen Creek, Corgan R. Archuleta Apr 2024

Designed For Life: Unearthing Just And Sustainable Urban Design Through The Daylighting Of Phalen Creek, Corgan R. Archuleta

Geography Honors Projects

This thesis conceptualizes a relational approach to urban design. Often separated from justice, I argue urban design can shape spaces to enable respectful and reciprocal human and more-than- human relationships. Focusing on Phalen Creek in Saint Paul, Minnesota, I illuminate just and sustainable possibilities between ecologically sustainable and socially inclusive design. Phalen Creek was a natural waterway buried in a pipe during 20th century urbanization to be partially reconstructed through daylighting. The Indigenous and Immigrant stories driving restoration expand urban design’s liberatory potential. Combining just sustainabilities with infrastructure theory and Indigenous Knowledges, I contend urban design offers a relational approach …


Estimating Effects Of Tourism Using Multiple Data Sources: The Miranda Tool As Part Of A Spatial Decision Support System For Sustainable Destination Development, Tobias Heldt Apr 2024

Estimating Effects Of Tourism Using Multiple Data Sources: The Miranda Tool As Part Of A Spatial Decision Support System For Sustainable Destination Development, Tobias Heldt

GSTC Academic Symposium - In conjunction with the GSTC Global Conference

Planning for sustainable mobility and destination development in rural areas is increasingly important when tourism grows in numbers. A key to address the challenge of transformation and adaptation of local communities to mitigate adverse effects in seasonal peak hours like traffic congestion, power failure, waste management and sewage flooding, is to properly estimate the number of visitors to a destination.

The problem of estimating tourism numbers is a known challenge since, for example, guest nights statistics are in-complete and non-commercial lodging (sharing solutions) are increasing. Recently, the promising utilization of mobile phone data has emerged as a means to estimate …


Mechanical Characterization Of Hemp, Jute, And Flax Based Natural Fibre Composites For Non-Structural Applications In Aircraft And Automobiles, Ravi Kumar B Apr 2024

Mechanical Characterization Of Hemp, Jute, And Flax Based Natural Fibre Composites For Non-Structural Applications In Aircraft And Automobiles, Ravi Kumar B

Theses and Dissertations

Demand for reducing energy consumption and detrimental environmental impacts after the effective lifetime of an engineering material are the major driving factors for the development of natural fibre reinforced composites (NFRCs) in various sectors. Compared to synthetic fibre like carbon-fibres or Kevlar, natural fibres provide several benefits including light weight, inexpensive, recyclability, superior specific strength, biodegradable, non-toxic during handling, and less energy intensive during manufacturing. This doctoral work presents observations from mechanical tests and interpretations on the suitability of natural fibre reinforced composites for less heavily loaded engineering applications areas.

In the first stage, jute, flax, and hemp fibres were …


Deficiencies In Safe Practices By Pilots Operating General Aviation Aircraft In Weather Conducive For Icing, Douglas Boyd Phd, Thomas Guinn Phd Apr 2024

Deficiencies In Safe Practices By Pilots Operating General Aviation Aircraft In Weather Conducive For Icing, Douglas Boyd Phd, Thomas Guinn Phd

Journal of Aviation Technology and Engineering

Introduction: Flights of general aviation aircraft in icing conditions pose safety hazards especially since few airplanes are equipped with ice protection systems (FIKI). Herein, we sought to answer the following questions not previously addressed: (i) Has the general aviation icing-related accident rate declined over time? (ii) Which phase(s) of flight lead(s) to the highest fraction of fatal accidents? (iii) Do general aviation pilots adhere to safe practices when operating in forecasted icing?

Methods: Retrospectively, icing-related accidents were per the National Transportation Safety Board database. Prospectively, non-FIKI single-engine airplanes, operating in forecasted icing, were tracked (January–March 2023) using FlightAwareR. Presumptive icing …


Evolving Hangwuran City Development Model Through Partial Least Square Approach In North-Central Nigeria, Samuel Medayese, Hangwelani H. Magidimisha-Chipungu, Lovemore Chipungu Apr 2024

Evolving Hangwuran City Development Model Through Partial Least Square Approach In North-Central Nigeria, Samuel Medayese, Hangwelani H. Magidimisha-Chipungu, Lovemore Chipungu

CSID Journal of Infrastructure Development

The need for a paradigmatic shift in city development ideology has become increasingly evident over the years. In response to this need, the Hangwurian City Development Model was developed to establish a connection between the concepts of environmental awareness, urban governance, and management. This model also integrates sustainable urban development, urban liveability, and inclusive physical development. The research sets a critical objective of analyzing the significant levels of various indicator variables. The exploratory research utilized partial least squares (PLS) via SmartPLS to evaluate the variables, collecting quantitative data through the open data toolkit from three selected cities: Lokoja, Minna, and …


Condition Of Drainage System And Its Impact On The Residents Of Mowe, Ogun State, Nigeria, Ayodeji Olusola Ajayi, Testimony Ayomide Oladiran, Ismail Adedapo Oyerinde, Aderonke Olufunmi Ajayi, Adonis Busuyi Fakanlu Apr 2024

Condition Of Drainage System And Its Impact On The Residents Of Mowe, Ogun State, Nigeria, Ayodeji Olusola Ajayi, Testimony Ayomide Oladiran, Ismail Adedapo Oyerinde, Aderonke Olufunmi Ajayi, Adonis Busuyi Fakanlu

CSID Journal of Infrastructure Development

This study examines the impacts of drainage infrastructure conditions on Mowe, Ogun State, residents. The study used a quantitative research design, using a systematic random sampling technique to select ten (10) residential estates (three public-owned and seven privately owned) in the study area. In all, 107 residents were sampled using a structured questionnaire. The data collected was analysed using descriptive statistics. Based on the findings of this study, it was evident that the surface drainage system, mainly constructed with sandcrete blocks, was predominant in the study area. The result established that the drainage's minimum height in the study area was …


Partnership And Coalition Efforts For Community-Based Research: Towards A Liveable Urban And Rural Settlement In Kwazulu-Natal, Sibongile A. Ngcobo, Nene E. Khalema, Tawanda Makusha Apr 2024

Partnership And Coalition Efforts For Community-Based Research: Towards A Liveable Urban And Rural Settlement In Kwazulu-Natal, Sibongile A. Ngcobo, Nene E. Khalema, Tawanda Makusha

CSID Journal of Infrastructure Development

This paper examines the role of community partnerships and coalitions in the intricate and constantly evolving dynamics of communities in KwaZulu-Natal, South Africa. Various aspects of the community context, such as socioeconomic conditions, geography, environmental factors, demographics, community politics, and cultural norms, often influence these community partnerships and coalitions. This study adopted the Community Coalition Action Theory as an organisational framework to examine the efforts of coalitions and partnerships in community-based research. The research applied a mixed-methods approach. This included a survey and individual interviews within the research organisation responsible for multiple community-based projects in rural and urban areas of …


Solving Water Resources Problems - Water Saving In The Republic Of Uzbekistan, Rustam Muxammatdjanovich Raximov Apr 2024

Solving Water Resources Problems - Water Saving In The Republic Of Uzbekistan, Rustam Muxammatdjanovich Raximov

Technical science and innovation

In this article we will talk about the problems of water resources in the Republic of Uzbekistan. The problem of drinking water supply, solutions to provide drinking water to the population of Uzbekistan. The largest consumers of fresh water in Uzbekistan are farmers. Due to outdated infrastructure, 40% of water is wasted. Rising food prices and the risk of spreading disease are the first signs of water shortages that we may experience in the coming еars. Uzbekcosmos told how to solve the problem. Water is an invaluable resource used not only in the home, but also in the production and …


Theory Of Development And Improvement Of The Mathematical Model Of The Methodology Of Public Control In The Management Of Occupational Safety And Industrial Risks, Aliakbar Khamidullaevich Rasulev, Sunnatilla Suleymanovich Suleymanov, Nodira Bakhadirzhanovna Gaibnazarova Apr 2024

Theory Of Development And Improvement Of The Mathematical Model Of The Methodology Of Public Control In The Management Of Occupational Safety And Industrial Risks, Aliakbar Khamidullaevich Rasulev, Sunnatilla Suleymanovich Suleymanov, Nodira Bakhadirzhanovna Gaibnazarova

Technical science and innovation

The article develops and analyzes a mathematical model based on a logical flowchart of the methodology of public control in the management of occupational safety and industrial risks and probability theory, according to the model, the results of compliance with the requirements of social cooperation on occupational safety lead to a sharp increase in the probability of reliability, management efficiency becomes higher. Analysis of the mathematical model of the developed logical flowchart based on probability theory has shown that when the parties cooperate to monitor the results of compliance with labor protection requirements, they lead to a sharp increase in …


Implementation Of A Realistic Artificial Data Generator For Crash Data Generation, Lauren Hoover, Md. Istiak Jahan, Tanmoy Bhowmik, Sudipta Dey Tirtha, Karthik C. Konduri, John Ivan, Kai Wang, Shanshan Zhao, Joshua Auld, Naveen Eluru Apr 2024

Implementation Of A Realistic Artificial Data Generator For Crash Data Generation, Lauren Hoover, Md. Istiak Jahan, Tanmoy Bhowmik, Sudipta Dey Tirtha, Karthik C. Konduri, John Ivan, Kai Wang, Shanshan Zhao, Joshua Auld, Naveen Eluru

Civil and Environmental Engineering Faculty Publications and Presentations

In this paper, a framework is outlined to generate realistic artificial data (RAD) as a tool for comparing different models developed for safety analysis. The primary focus of transportation safety analysis is on identifying and quantifying the influence of factors contributing to traffic crash occurrence and its consequences. The current framework of comparing model structures using only observed data has limitations. With observed data, it is not possible to know how well the models mimic the true relationship between the dependent and independent variables. Further, real datasets do not allow researchers to evaluate the model performance for different levels of …


Trend Tour, Aaron Ancheta, Khushboo Gupta, Xiomara Quinonez Apr 2024

Trend Tour, Aaron Ancheta, Khushboo Gupta, Xiomara Quinonez

Computer Science and Engineering Senior Theses

Choosing outfits as a college student can prove challenging – especially for new college students and students new to the area where their college is. Trend Tour, our web-based application, displays what the fashion trends are in the user's college and near their area. This helps the user with ideas on how to dress. Furthermore, the user can change the color, silhouette, and/or accessories of outfits they want to see at that college and near their area. This web application aims to help college students feel more confident and comfortable.


Reducing Vehicle Licensing And Titling Fraud, Mallory Brown, Andrew Martin, Jeeyen Koo, Jennifer Walton Apr 2024

Reducing Vehicle Licensing And Titling Fraud, Mallory Brown, Andrew Martin, Jeeyen Koo, Jennifer Walton

Kentucky Transportation Center Research Report

This study reviews Kentucky’s vehicle licensing and registration program, evaluates methods of motor vehicle title fraud, examines current anti-fraud mechanisms in Kentucky, reports on vehicle titling and anti-fraud efforts in other states, assesses Ohio’s vehicle inspection program, and develops a proposal for a new Kentucky rebuilt title inspection program. Researchers developed the proposal based on historical Kentucky vehicle registration and titling data, a survey of other states, and other information provided by Kentucky’s Division of Motor Vehicle Licensing and other agency partners. Kentucky historical data revealed consistently high numbers of salvage title applications as well as spatial concentration in rebuilt …


Enhancement Of Rainfall Prediction And Satellite Precipitation Estimates: A Machine Learning Approach For United Arab Emirates, Faisal Baig Apr 2024

Enhancement Of Rainfall Prediction And Satellite Precipitation Estimates: A Machine Learning Approach For United Arab Emirates, Faisal Baig

Dissertations

The accurate estimation of rainfall in arid regions presents a significant challenge due to sparse ground observations and complex atmospheric dynamics. This dissertation investigates various aspects of rainfall estimation and prediction in the United Arab Emirates (UAE), employing Satellite Precipitation Products (SPPs) and Machine Learning (ML) techniques. The research is structured around four key articles, each addressing different facets of the overarching theme. The first publication examines rainfall variability, consistency, and concentration in the UAE by comparing satellite precipitation products with rain gauge observations, highlighting the discrepancies between the two data sources. The second publication evaluates the performance of precipitation …


Design Of Sustainable & Affordable Housing For Disadvantaged Communities In Nicaragua, Guillermo Terán Apr 2024

Design Of Sustainable & Affordable Housing For Disadvantaged Communities In Nicaragua, Guillermo Terán

Civil, Environmental and Sustainable Engineering Senior Theses

Addressing Nicaragua's urgent housing needs, this project transforms a conventional CMU block design into a sustainable and affordable model using local, structural bamboo and adobe plaster. It includes appropriate member size connections, local-code compliant construction drawings, cost estimation and logistics, offering an eco-friendly, affordable housing solution for local communities. The scope of this project can be emphasized with the three words from the project title which are design, sustainable & affordable. The design aspect of this project involved producing detailed architectural and engineering drawings for the housing model, incorporating structural design to ensure the safety, stability and durability of the …


Preserving Location Authenticity: Multi-Sensor System To Thwart Gps Spoofing In Self-Driving Vehicles, Peng Jiang Apr 2024

Preserving Location Authenticity: Multi-Sensor System To Thwart Gps Spoofing In Self-Driving Vehicles, Peng Jiang

Electrical & Computer Engineering Theses & Dissertations

The ubiquity of the Global Positioning System (GPS) has cemented its role as the cornerstone for an array of location-based services and navigation systems, spanning applications from autonomous vehicles and drones to maritime vessels and wearable technology. Nonetheless, ensuring the integrity of reported geographical coordinates poses a formidable challenge, owing to the proliferation of diverse GPS spoofing tools. This predicament is compounded by the pervasive availability of tools like Fake GPS, Lockito, and software-defined radios, enabling even unsophisticated users to commandeer and disseminate counterfeit GPS coordinates. This dissertation undertakes the task of devising an encompassing and resilient framework, integrating a …


Accommodating Spatio-Temporal Dependency In Airline Demand Modeling, Sudipta Dey Tirtha, Tanmoy Bhowmik, Naveen Eluru Apr 2024

Accommodating Spatio-Temporal Dependency In Airline Demand Modeling, Sudipta Dey Tirtha, Tanmoy Bhowmik, Naveen Eluru

Civil and Environmental Engineering Faculty Publications and Presentations

The objective of the current study is to examine monthly air passenger departures at the airport level considering spatial interactions between airports. In this study, we develop a novel spatial grouped generalized ordered probit (SGGOP) model system of monthly air passenger departures at the airport level. Specifically, we estimate two variants of spatial models including spatial lag model and spatial error model. In the presence of repeated demand measures for the airports, we also consider temporal variations of spatial correlation effects among proximally located airports by employing space and time-based weight matrix. The proposed model is estimated using monthly air …


Bim-Gis Integration An Innovative Tool To Enhance Urban Heritage Management In The Digital Era, Ali H. Misilmani, Ibtihal Y. El-Bastawissi, Hany Ayad, Samer El Sayary Mar 2024

Bim-Gis Integration An Innovative Tool To Enhance Urban Heritage Management In The Digital Era, Ali H. Misilmani, Ibtihal Y. El-Bastawissi, Hany Ayad, Samer El Sayary

Architecture and Planning Journal (APJ)

Due to the great loss of the cities’ ancient monuments and urban heritage resulting from either natural disasters or irresponsible human actions, it has become very urgent to find an innovative tool for restoring and conserving historical buildings in a smart and sustainable way. Furthermore, this tool can help in decision making regarding the selection of appropriate materials and intervention works. Such objectives have been realized through innovative integration of BIM & GIS to enhance urban heritage management. BIM data has been imported into the GIS environment to be visualized in 3D and analyse different scenarios for buildings’ sustainable development. …


Advancing Depth-Storage-Discharge Modeling In Regional Hydrology, Fahad Alshehri Mar 2024

Advancing Depth-Storage-Discharge Modeling In Regional Hydrology, Fahad Alshehri

USF Tampa Graduate Theses and Dissertations

This dissertation presents the development of an innovative approach to populating rating characteristics and supporting hydrologic modeling, designed to simplify complex real-world hydrological systems and accurately estimate their responses to rainfall, runoff, baseflow and evaporation stresses. The core of this research addresses the challenges inherent in characterizing hydrography elements in hydrologic modeling, particularly in regions lacking comprehensive stream reach survey data, flow and stage. This issue is pronounced in areas with extensive wetland hydrography, where traditional modeling requires intensive manual calibration, and course rating data that are often unavailable. To overcome these challenges, this study introduces a novel procedure that …


Evaluating The Environmental Impacts Of U.S. Historical Oil Spill Incidents, Yiming Liu, Hua Cai Mar 2024

Evaluating The Environmental Impacts Of U.S. Historical Oil Spill Incidents, Yiming Liu, Hua Cai

Graduate Industrial Research Symposium

Exposure to risks associated with the production and usage of products, particularly oil, poses significant threats to both ecological systems and human health. Notable examples include the Gulf War Oil Spill (1991) and the Deepwater Horizon Oil Spill (2010). However, numerous smaller-scale oil spills, which collectively contribute to substantial oil releases, often remain overlooked. To fill this gap, our study first developed a detailed oil spill incidents database, covering 1967 to 2023. We quantified the released amount (RA) of oil spills recorded by the National Oceanic and Atmospheric Administration (NOAA). Subsequently, we utilized life cycle impact indicators in ReCiPe to …


Assessment Of Educational Facilities In Osogobo Metropolis Nigeria, Dele S. Ogundahunsi, Martins B. Gasu, Samuel B. Adedotun, Olayiwola Olayode, Akintayo O. Ojo, Christiana Olayode Mar 2024

Assessment Of Educational Facilities In Osogobo Metropolis Nigeria, Dele S. Ogundahunsi, Martins B. Gasu, Samuel B. Adedotun, Olayiwola Olayode, Akintayo O. Ojo, Christiana Olayode

CSID Journal of Infrastructure Development

This study assessed educational facilities in the Osogbo metropolis, Nigeria, aiming to evaluate the available educational facilities, examine student and staff satisfaction levels, and analyze their availability across schools in the area. The sample consisted of 476 schools, from which 73 were randomly selected. A multistage sampling procedure was employed to sample 1,863 pupils/students and 87 teachers for questionnaire administration, complemented by observation. Data were analyzed using Mean Weighted Average, Summation of Weighted Value, and Analysis of Variance. Findings showed that 63.4% of primary schools had the listed facilities, while 75% of secondary schools reported 81% availability. Public primary school …


Investigating Customer Churn In Banking: A Machine Learning Approach And Visualization App For Data Science And Management, Pahul Preet Singh, Fahim Islam Anik, Rahul Senapati, Arnav Sinha, Nazmus Sakib, Eklas Hossain Mar 2024

Investigating Customer Churn In Banking: A Machine Learning Approach And Visualization App For Data Science And Management, Pahul Preet Singh, Fahim Islam Anik, Rahul Senapati, Arnav Sinha, Nazmus Sakib, Eklas Hossain

Electrical and Computer Engineering Faculty Publications and Presentations

Customer attrition in the banking industry occurs when consumers quit using the goods and services offered by the bank for some time and, after that, end their connection with the bank. Therefore, customer retention is essential in today’s extremely competitive banking market. Additionally, having a solid customer base helps attract new consumers by fostering confidence and a referral from a current clientele. These factors make reducing client attrition a crucial step that banks must pursue. In our research, we aim to examine bank data and forecast which users will most likely discontinue using the bank’s services and become paying customers. …


Positioning, Navigation, And Timing (Pnt) Study For Select Multibody Environments, Kaitlin R. Roberts Mar 2024

Positioning, Navigation, And Timing (Pnt) Study For Select Multibody Environments, Kaitlin R. Roberts

Theses and Dissertations

In the renewed 21st-century race to the Moon, the demand for heightened mission capabilities in the cislunar region, lunar surface, and beyond is imperative. With an escalating number and complexity of lunar missions, persistent positioning, navigation, and timing (PNT) capabilities are becoming paramount. This thesis presents innovative lunar PNT architectures designed to provide continuous coverage of the lunar South Pole, near-continuous coverage of the entire lunar surface, and coverage of the Earth-Moon Corridor. As space faring countries advance from lunar exploration to Mars, similar assets are essential for astronaut exploration in this extraterrestrial environment. Additionally, this thesis introduces and meticulously …


An Exploratory Framework For Benchmarking Vehicle Miles Traveled (Vmt) Estimates Associated With University Campuses, Troy Kawahara Mar 2024

An Exploratory Framework For Benchmarking Vehicle Miles Traveled (Vmt) Estimates Associated With University Campuses, Troy Kawahara

Master's Theses

Although vehicle miles traveled (VMT) has become the standard for assessing transportation related impacts in California, some have concerns that many VMT estimates are not properly grounded or informed by real world data, potentially resulting in flawed estimates and impact assessments. This is especially true of special generators, like college and university campuses, which have complex travel patterns distinct from that of the general public. This thesis attempts to resolve a significant disparity observed between two credible VMT estimates for Cal Poly’s campus wide VMT. As part of a campus master planning effort, a VMT estimate was produced in 2019 …


Preliminary Assessment Of Cislunar Disposal Orbits, Ryan M. Sargent Mar 2024

Preliminary Assessment Of Cislunar Disposal Orbits, Ryan M. Sargent

Theses and Dissertations

This thesis investigates the disposal of end-of-life spacecraft from key orbits with a focus on minimizing delta-v expenditure and preventing debris propagation. Simulated Lyapunov and halo orbits around the L2 Lagrange point are analyzed for disposal feasibility. Both impulsive and continuous thrust methods are explored to achieve disposal trajectories. Continuous thrust will be modeled after a Hall thruster utilizing electric propulsion. Leveraging the Circular Restricted Three Body Problem framework, low delta-v cost trajectories are computed, with a multi-level correction algorithm optimizing total delta-v via heteroclinic connections. The study assesses various delta-v amounts for Earth-Moon system escape and evaluates the potential …