Physical Sciences and Mathematics Commons^™

Detection Of Jamming Attacks In Vanets, Thomas Justice

Undergraduate Honors Theses

A vehicular network is a type of communication network that enables vehicles to communicate with each other and the roadside infrastructure. The roadside infrastructure consists of fixed nodes such as roadside units (RSUs), traffic lights, road signs, toll booths, and so on. RSUs are devices equipped with communication capabilities that allow vehicles to obtain and share real-time information about traffic conditions, weather, road hazards, and other relevant information. These infrastructures assist in traffic management, emergency response, smart parking, autonomous driving, and public transportation to improve roadside safety, reduce traffic congestion, and enhance the overall driving experience. However, communication between the …

Development Of Back-Scatter And Pile-Up Identification For Ucna+, Amelia Greathouse

Undergraduate Honors Theses

The UCNA Experiment at the Los Alamos Neutron Science Center (LANSCE) uses

an electron spectrometer to observe angular correlations between the neutron spin and the momenta of beta particles emitted during the process of beta (β) decay. Combined with neutron lifetime measurements, these observations probe physics beyond the standard model. In recent years there has been an effort to modernize the equipment to reduce the physical limitations of the experiment. The new prototype helps to reduce error via use of silicon photo-multipliers (SiPMs) and the SiPMs also have a greater quantum efficiency than the photomultiplier tubes (PMTs). However, there is …

Exploration And Statistical Modeling Of Profit, Caleb Gibson

Undergraduate Honors Theses

For any company involved in sales, maximization of profit is the driving force that guides all decision-making. Many factors can influence how profitable a company can be, including external factors like changes in inflation or consumer demand or internal factors like pricing and product cost. Understanding specific trends in one's own internal data, a company can readily identify problem areas or potential growth opportunities to help increase profitability.

In this discussion, we use an extensive data set to examine how a company might analyze their own data to identify potential changes the company might investigate to drive better performance. Based …

Parameter Estimation For Patient Enrollment In Clinical Trials, Junyan Liu

Undergraduate Honors Theses

In this paper, we study the Poisson-gamma model for recruitment time in clinical trials. We proved several properties of this model that match our intuitions from a reliability perspective, did simulations on this model, and used different optimization methods to estimate the parameters. Although the behaviors of the optimization methods were unfavorable and unstable, we identified certain conditions and provided potential explanations for this phenomenon and further insights into the Poisson-gamma model.

Ensuring Non-Repudiation In Long-Distance Constrained Devices, Ethan Blum

Undergraduate Honors Theses

Satellite communication is essential for the exploration and study of space. Satellites allow communications with many devices and systems residing in space and on the surface of celestial bodies from ground stations on Earth. However, with the rise of Ground Station as a Service (GsaaS), the ability to efficiently send action commands to distant satellites must ensure non-repudiation such that an attacker is unable to send malicious commands to distant satellites. Distant satellites are also constrained devices and rely on limited power, meaning security on these devices is minimal. Therefore, this study attempted to propose a novel algorithm to allow …

Interannual Variation Of Ichthyofaunal Utilization Of A Man-Made Salt Marsh Creek In Mission Bay, California, Maria Angst

Undergraduate Honors Theses

Marsh restoration and creation are increasingly being used to mitigate Southern California’s drastic decline in wetlands due to human activities. This study used minnow traps to resample the ichthyofauna of a created marsh (Crown Point Mitigation Site; CPMS) and an adjacent natural marsh (Kendall Frost) in Mission Bay, California, 26 years following the marsh creation. Data from this study were compared to data collected immediately after marsh creation from 1995-1998, and from 2021. Fishes captured included Fundulus parvipinnis, Gillichthys mirabilis, Acanthagobius flavimanus, Ctenogobius sagittula, and Mugil cephalus. Species richness and dominance measures were higher in the natural relative to the …

Understanding The Connection Between Gypsum Blooms And Human Health At The Salton Sea, Isabel Ichiyama

Undergraduate Honors Theses

The Salton Sea is a closed hypersaline lake in Southern California that has been receiving little input over the past few decades, leading to desiccation that is rapidly increasing every year. This large-scale evaporation of the sea has led to increased dissolved solutes, high salinity, and gypsum blooms. Gypsum blooms, the precipitation of gypsum (CaSO42H2O) in the sea, have been a prominent facet of the sea and their distribution is well known. However, much of their chemistry and potential health hazards are still undetermined. Potential health effects from gypsum salt, an atmospheric dust particle present at the sea, have known …

Algorithmic Bias: Causes And Effects On Marginalized Communities, Katrina M. Baha

Undergraduate Honors Theses

Individuals from marginalized backgrounds face different healthcare outcomes due to algorithmic bias in the technological healthcare industry. Algorithmic biases, which are the biases that arise from the set of steps used to solve or analyze a problem, are evident when people from marginalized communities use healthcare technology. For example, many pulse oximeters, which are the medical devices used to measure oxygen saturation in the blood, are not able to accurately read people who have darker skin tones. Thus, people with darker skin tones are not able to receive proper health care due to their pulse oximetry data being inaccurate. This …

A Satellite Imagery Approach To Estimating Migratory Flows In Guatemala Using Convolutional Neural Networks, Sarah Larimer

Undergraduate Honors Theses

Being able to predict migratory flows is important in ensuring political, social, and economic stability. In the wake of violence, unrest, natural disasters, and social pressures, millions of mi- grants have fled Central America in search of a better life. However, due to the infrequent nature and high cost of census data, there is a need for a more remote and up to date approaches. Con- volutional Neural Networks offer a computer vision based approach that is cheaper and with significantly less lag. In this study, we seek to evaluate the effectiveness of different convolu- tional neural networks in predicting …

Considering The Accuracy Of Fiat Boundaries: Ontology And Quantification, Lydia Troup

Undergraduate Honors Theses

Administrative boundaries - i.e., states, counties, or districts - are fiat boundaries; they exist purely as defined by human interpretation. Because of this, and despite their critical importance to government functions, the accuracy of data products claiming to represent such boundaries is difficult to measure. Here, I explore this topic using three boundary data sets: the open source geoBoundaries data set, the humanitarian UN OCHA’s Common Operational Datasets (COD), and Esri’s commercial administrative divisions 0 and 1 data sets in the Living Atlas. The accuracy of each was quantified as the percent overlap between each data set and an authoritative …

Sexual Dimorphism Of Glomerular Capillary Morphology In Rats, Zackarias Coker

Undergraduate Honors Theses

Chronic kidney disease (CKD) progresses faster in males than females; however, the underlying mechanisms remain poorly understood. Sex differences in glomerular capillary morphology has been hypothesized to contribute, in part, to the increased susceptibility to hypertension-induced renal injury and CKD progression in males, but this has not been investigated. The goal of the present study was to assess glomerular capillary morphology in male vs. female rats with intact kidneys and after uninephrectomy (UNX). We hypothesized that glomerular capillary radii (R_CAP) and length (L_CAP) would be greater in male rats.

Male (n=4) and female (n=4) with intact …

Development Of A 780 Nm External Cavity Diode Laser For Rubidium Spectroscopy, Catherine Sturner

Undergraduate Honors Theses

This thesis describes the work done to improve an external cavity diode laser. These improvements consisted of constructing an insulated housing to stabilize the temperature of the laser, tuning the proportional-integral-derivative feedback of the temperature controller, achieving resonance frequencies of rubidium, and implementing and optimizing feed-forward scanning of the frequency of the laser. The laser was then successfully used to measure the linewidth of another laser in the laboratory to better understand how that laser could be best used. The knowledge gained in this thesis can also be used to change the frequency of the laser to achieve other resonances …

Black Hole Entropy In Ads/Cft And The Schwinger-Keldysh Formalism, Luke Mrini

Undergraduate Honors Theses

The Schwinger-Keldysh formalism for non-equilibrium field theory provides valuable tools for studying the black hole information loss paradox. In particular, there exists a Noether-like procedure to obtain the entropy density of a system by a discrete Kubo-Martin-Schwinger (KMS) variation of the action. Here, this Noether-like procedure is applied to the boundary action of an asymptotically anti-de Sitter (aAdS) black hole spacetime in maximally extended Kruskal coordinates. The result is the Kubo formula for shear viscosity, which is known in theories with an Einstein gravity dual to have a universal, constant ratio with the entropy density and is proportional to the …

Automorphisms Of A Generalized Quadrangle Of Order 6, Ryan Pesak

Undergraduate Honors Theses

In this thesis, we study the symmetries of the putative generalized quadrangle of order 6. Although it is unknown whether such a quadrangle Q can exist, we show that if it does, that Q cannot be transitive on either points or lines. We first cover the background necessary for studying this problem. Namely, the theory of groups and group actions, the theory of generalized quadrangles, and automorphisms of GQs. We then prove that a generalized quadrangle Q of order 6 cannot have a point- or line-transitive automorphism group, and we also prove that if a group G acts faithfully on …

Monoenergetic Neutrinos From Wimp Annihilations In Jupiter, George French

Undergraduate Honors Theses

Several important lines of evidence point to the existence of dark matter, but it has not yet been experimentally detected. There are several proposed candidates for what dark matter is like, the most popular being weakly interacting massive particles (WIMPs). It has been well-established in the literature that WIMPs would be captured by the Sun after scattering off of atomic nuclei to a velocity lower than the escape velocity. Over time, many WIMPs would be captured and begin to annihilate in the solar core; this would result in the production of kaons that decay at rest into monoenergetic 236 MeV …

Materials Characterization For Microwave Atom Chip Development, Jordan Shields

Undergraduate Honors Theses

This thesis describes research to characterize materials to be implemented on a microwave atom trap chip, which will be able to trap and spatially manipulate atoms using the spin-specific microwave AC Zeeman effect. Potential applications of this research include atom-based interferometry and quantum computing.

Namely, this thesis describes the characterization of the following: (1) the dielectric constant of a well-characterized substrate, Rogers RO4350B, in order to provide proof-of-concept for a method that can be applied to the chip’s substrate, aluminum nitride (AlN), (2) the maximum current that will be able to be applied to the chip, and (3) surface roughness …

Fecal Pellet Production By North Atlantic Zooplankton, Michael Gibson

Undergraduate Honors Theses

Fecal pellet carbon (FPC) production by zooplankton is a significant component of the ocean’s biological carbon pump: the suite of biological processes that mediate export of carbon to the deep ocean, ultimately leading to the sequestration of atmospheric carbon dioxide in the ocean. In this study, mesozooplankton (zooplankton 0.2 mm to ~2 cm) were collected from the epipelagic zone in the temperate North Atlantic Ocean during day and night in May 2021. Zooplankton were live separated into five size fractions and incubated on board ship in natural surface seawater to measure fecal pellet production rate of the mixed mesozooplankton community. …

Seeing What We Can't: Evaluating Implicit Biases In Deep Learning Satellite Imagery Models Trained For Poverty Prediction, Joseph O'Brien

Undergraduate Honors Theses

Previous studies have sought to use Convolutional Neural Networks for regional estimation of poverty levels. However, there is limited research into possible implicit biases in deep neural networks in the context of satellite imagery. In this work, we develop a deep learning model to predict the tertile of per-capita asset consumption, trained on satellite imagery and World Bank Living Standards Measurements Study data. Using satellite imagery collected via survey location data as inputs, we use transfer learning to train a VGG-16 Convolutional Neural Network to classify images based on per-capita consumption. The model achieves an $R^2$ of .74, using thousands …

A Study Of Reciprocal Underwater Motion And Its Use In Algae Harvesting, Marguerite Bright

Undergraduate Honors Theses

In 2009, many research groups at different companies and universities were funded by Statoil to study the use of algae as a potential biofuel. Combined with the Chesapeake Bay TMDL given by the EPA, a team at William & Mary and VIMS studied the growth and harvest of wild algae in the York River. This method also removed harmful nutrients such as nitrogen and phosphorus from the waterways. Other independent research projects stemmed from this. In 2014, a research team sought to commercialize and automate the IWAGS system, and found that a single oscillating blade was the most effective. This …

Identifying Social Media Users That Are Susceptible To Phishing Attacks, Zoe Metzger

Undergraduate Honors Theses

Phishing scams are a billion-dollar problem. According to Threatpost, in 2020, business email compromise phishing attacks cost the US economy $ 1.8 billion. Social media phishing scams are also on the rise with 74% of companies experiencing social media attacks in 2021 according to Proofpoint. Educating users about phishing scams is an effective strategy for reducing phishing attacks. Despite efforts to combat phishing, the number of attacks continues to rise, likely indicative of a reticence of users to change online behaviors. Existing research into predicting vulnerable social media users that are susceptible to phishing mostly focuses on content analysis of …

Examining Factors Using Standard Subspaces And Antiunitary Representations, Paul Anderson

Undergraduate Honors Theses

In an effort to provide an axiomization of quantum mechanics, John von Neumann and Francis Joseph Murray developed many tools in the theory of operator algebras. One of the many objects developed during the course of their work was the von Neumann algebra, originally called a ring of operators. The purpose of this thesis is to give an overview of the classification of elementary objects, called factors, and explore connections with other mathematical objects, namely standard subspaces in Hilbert spaces and antiunitary representations. The main results presented here illustrate instances of these interconnections that are relevant in Algebraic Quantum Field …

Spatial Variability Of Alkali-Metal Polarization, Lauren Vannell

Undergraduate Honors Theses

An experiment was conducted at William & Mary to study how alkali polarization varies spatially in a spherical cell during the process of optical pumping. Similar cells are used to study the neutron via electron scattering from polarized 3He nuclei, and those experiments could be improved if alkali polarization is maximized and uniformly distributed throughout the cell. The results of this experiment indicate that the alkali polarization is non-uniform and more heavily concentrated on the side of the cell facing the pump laser.

Kfactorvae: Self-Supervised Regularization For Better A.I. Disentanglement, Joseph S. Lee

Undergraduate Honors Theses

Obtaining disentangled representations is a goal sought after to make A.I. models more interpretable. Studies have proven the impossibility of obtaining these kinds of representations with just unsupervised learning, or in other words, without strong inductive biases. One strong inductive bias is a regularization term that encourages the invariance of factors of variations across an image and a carefully selected augmentation. In this thesis, we build upon the existing Variational Autoencoder (VAE)-based disentanglement literature by utilizing the aforementioned inductive bias. We evaluate our method on the dSprites dataset, a well-known benchmark, and demonstrate its ability to achieve comparable or higher …

Synthesis And Characterization Of Nanocomposite Sensing Films For Breath Sensors, Tara Mercer

Undergraduate Honors Theses

Lung cancer is one of the most common and fatal cancers today, infecting 1 in 16 people, and killing well over a million patients per year. Currently, lung cancer is detected usually in stages three and four by quite costly and invasive methods, which shows only a survival rate of 10%. Breath sensors provide a low-cost and non-invasive technique for early screening of lung cancer. The breath sensors use assemblies of gold nanoparticles to identify lung cancer, specifically by identifying and quantifying specific volatile organic compound (VOC) concentrations found in the breath of lung cancer patients. This thesis describes a …

Pion Detection For The Moller Parity-Violating Electron Scattering Experiment, Michael Tristan Hurst

Undergraduate Honors Theses

The MOLLER Experiment at Jefferson Lab intends to make a precise measurement of the weak charge of the electron through parity-violating electron scattering. To achieve the level of precision required for the experiment, background rates of events other than electron-electron scattering must be known. Working with data from Monte-Carlo simulations created using a GEANT4 simulation package, I show that the combined signal from two existing detector subsystems of the MOLLER experiment allow for particle identification between electron and pion events. I worked to optimize an additional ‘Pion Exit Scintillator’ which improves the ability to distinguish particle identity at the cost …

Synthesis Of A Phenyl Substituted Zinc Dipyrrin Complex For The Purpose Of Analyzing Aromatic Substitutions On The Characteristics Of Compounds Of This Class, Kole Owen

Undergraduate Honors Theses

The field of photochemistry is as innovative in development as it is broad in application. However, utilization of energy from the sun’s electromagnetic radiation remains secondary to the combustion of fossil fuels for the global energy consumption. This is neither a sustainable nor renewable system, and it has contributed to a major decline in the health of our global environment as the greenhouse gases emission has led to an incline in global temperatures and ocean acidity. To develop effective ways to utilize solar energy, experimental effort is being directed towards the understanding of photosensitizers, molecules which absorb solar radiation and …

Mechanisms Of Formation Of Novel Guanine-Guanine Cross-Links As Major End Products During One-Electron Oxidation Of Guanine Derivatives, Evan Dunn

Undergraduate Honors Theses

Guanine (G), as the most oxidizable base in DNA, is the major focus of studies of oxidation damage to DNA. The present thesis reports the first detailed characterization of G dimerization products potentially resulting from recombination of neutral G• radicals. Previous research has discovered a novel type of products of G• dimerization, D1 and D2, formed from one-electron oxidation of G derivatives. However, the mechanism of this dimerization remains elusive. While there appears to be a tautomeric equilibrium between two forms of G•, G(N₁-H)• or G(N₂-H)•, it remains unclear which intermediate participates in the formation of …

Microwave Synthesis Of Carbon Dot Nanoparticles, Hayden Ferguson

Undergraduate Honors Theses

This study aimed to improve the known microwave method to produce carbon dot nanoparticles from ethylenediamine and citric acid. Carbon dots have recently gained much attention as they have diverse applications, such as bioimaging and drug delivery reagents as cancer theranostics. Research was focused on establishing the ideal time for the synthetic reaction to produce carbon dot nanoparticles with the microwave method. After several trials, the 16-minute trial provided the best results based on Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, fluorescence spectroscopy, and ultraviolet exposure.

Rbac Attack Exposure Auditor. Tracking User Risk Exposure Per Role-Based Access Control Permissions, Adelaide Damrau

Undergraduate Honors Theses

Access control models and implementation guidelines for determining, provisioning, and de-provisioning user permissions are challenging due to the differing approaches, unique for each organization, the lack of information provided by case studies concerning the organization’s security policies, and no standard means of implementation procedures or best practices. Although there are multiple access control models, one stands out, role-based access control (RBAC). RBAC simplifies maintenance by enabling administrators to group users with similar permissions. This approach to managing user permissions supports the principle of least privilege and separation of duties, which are needed to ensure an organization maintains acceptable user access …

Synthesis And Evaluation Of 1-Substituted Imidazo[4,5-C] Quinoline Tlr7 Agonists With Improved Potency, Emma Grace Deyoung

Undergraduate Honors Theses

TLR7 agonists are small molecules that are useful within cancer immunotherapy due to their ability to stimulate the TLR7 pathway resulting in NFκB activation, and cytokine release.1 Due to the risk of toxicity when delivered systemically, our team has employed a particular type of drug-delivery technology, Antibody Drug Conjugates (ADCs) to deliver these payloads directly to tumor tissue. The initial focus of this work was on E104 (8a), an imidazoquinoline TLR7 agonist, which was synthesized by the Tumey lab.1 However, the agonist was not sufficiently potent for many of the proposed applications of this technology, prompting a need to develop …