Digital Commons Network^™

Using Genetic Algorithms To Evolve Artificial Neural Networks, William T. Kearney

Honors Theses

This paper demonstrates that neuroevolution is an effective method to determine an optimal neural network topology. I provide an overview of the NeuroEvolution of Augmenting Topologies (NEAT) algorithm, and describe how unique characteristics of this algorithm solve various problem inherent to neuroevolution (namely the competing conventions problem and the challenges associated with protecting topological innovation). Parallelization is shown to greatly speed up efficiency, further reinforcing neuroevolution as a potential alternative to traditional backpropagation. I also demonstrate that appropriate parameter selection is critical in order to efficiently converge to an optimal topology. Lastly, I produce an example solution to a medical …

Development Of A Chemical Genetic Screen To Determine Synergistic Compounds With Laromustine In Treating Glioblastoma Multiforme Cultured Cells, Ryan Weeks

Honors Theses

Laromustine is a chemotherapeutic sulfonylhydrazine prodrug used in clinical trials to treat acute myeloid leukemia (AML) and glioblastoma multiforme (GBM). While treatment of AML with laromustine has more demonstrative clinical success, there are enough promising data against GBM to pursue additional pre-clinical and clinical experiments. To determine the synergistic effects caused by treating cultured GBM cells with laromustine and a library of FDA-approved compounds, a chemical genetic screen was developed. To optimize the screen, optimal cultured GBM cell seed density, growth period and maximum well capacity were determined. The treatment period for a lethal dose of laromustine in cultured GBM …

Experimental And Computational Study Of Methylphenylvinylidene And Its Rearrangements, Xi Yang

Honors Theses

In this study, the synthesis and properties were explored of the compound methylphenylvinylidene (MPV), a vinylidene carbene with methyl and phenyl groups as substituents. A phenanthrene-based precursor, 1-(1-phenylethylidene)-1a,9b-dihydro-1H-cyclopropa[l]phenanthrene, was synthesized in three steps and was subjected to photolysis in C₆D₆ at ambient temperature. During photolysis, the MPV carbene rearranged into 1-phenylpropyne via a 1,2-phenyl shift, instead of 1,2-methyl shift, confirmed by photolysis of ¹³C-labeled precursor. This experimental result is consistent with computational results using the CCSD(T)/cc-pVTZ//B3LYP/6-31+G* method. The calculations suggest that the 1,2-phenyl shift in singlet carbene requires 3.8 kcal/mol to overcome …

The Effect Of Cyanobacterium Gloeotrichia Echinulata In The Belgrade Lakes, Maine, Harriet T. Rothschild

Honors Theses

Gloeotrichia echinulata is a cyanobacteria species that has been increasingly forming blooms in oligotrophic lakes in the Northeastern United States. The Belgrade Lakes in central Maine have experienced increasing blooms over the past decades. Long Pond and Great Pond in the Belgrade Lakes region are popular locations for summer tourism and year-round residents. Research into G. echinulata is important to the Belgrade community because of potential effects to water quality, public health, and recreation. Studying G. echinulata bloom density throughout the summer and how it may affect the phosphorous cycle, the nitrogen cycle, and the plankton community will help scientists …

Don't Know, Do Not Resuscitate: A Principle For The Creation Of The Kingdom Of Ends In The Icu, Griffen Isaac Allen

Honors Theses

In the United States today 20% of all Americans die in Intensive Care Units, or ICUs. These were developed in the 50s, 60s, and 70s to centralize medical resources to help treat critically ill patients with new technologies like ventilators, dialysis, and other tools that are now commonplace. This occurred simultaneously with the emergence of individualistic autonomy, understood as the patient's right to dictate their treatment, as the dominant force in medical ethics. Ostensibly both of these developments would seem beneficial for patients. However, the ultimate result is overly aggressive care that strips patients of their dignity and ensures that …

Resonant Collisions Of Potassium Atoms, Philip Michael Adamson

Honors Theses

This thesis discusses an approach to excite potassium atoms to very highly excited states (Rydberg states), and then tune their energy levels to induce resonant collisions between atoms. Potassium gas is super-cooled to 1 mK and confined to a small volume in a magneto-optical trap. A 405 nm laser diode, electronically locked to a potassium vapor cell via Doppler free spectroscopy, excites these atoms from the 4s_1/2 state (ground state) to the 5p_3/2 state. A 978 nm laser then excites the 5p_3/2 to nd_3/2 or nd_5/2 transition, creating Rydberg atoms. Since there is no ground …

Are Tax Exemptions For "Churches" A Blessing Or A Curse For Taxpayers?, Hannah Bauman

Honors Theses

This paper focuses on the rules and requirements governing the participation of religious organizations as defined in IRC § 501(c)(3) in the political process. Included in this is a study of historical events and case law both for and against the participation of religious organizations in politics.

Partitioning Groups With Difference Sets, Rebecca Funke

Honors Theses

This thesis explores the use of difference sets to partition algebraic groups. Difference sets are a tool belonging to both group theory and combinatorics that provide symmetric properties that can be map into over mathematical fields such as design theory or coding theory. In my work, I will be taking algebraic groups and partitioning them into a subgroup and multiple McFarland difference sets. This partitioning can then be mapped to an association scheme. This bridge between difference sets and association schemes have important contributions to coding theory.

Real-Time Translation Of American Sign Language Using Wearable Technology, Jackson Taylor

Honors Theses

The goal of this work is to implement a real-time system using wearable technology for translating American Sign Language (ASL) gestures into audible form. This system could be used to facilitate conversations between individuals who do and do not communicate using ASL. We use as our source of input the Myo armband, an affordable commercially-available wearable technology equipped with on-board accelerometer, gyroscope, and electromyography sensors. We investigate the performance of two different classification algorithms in this context: linear discriminant analysis and k-Nearest Neighbors (k-NN) using various distance metrics. Using the k-NN classifier and windowed dynamic time …

The White-Nose Syndrome Transcriptome: Exploring The Putative Fungal Virulence Genes Of Pseudogymnoascus Destructans., Sophia Marie Reeder

Honors Theses

White-nose syndrome (WNS) in North American bats is caused by an invasive cutaneous infection by the psychrophilic fungus Pseudogymnoascus destructans (P. destructans). In a previous study, we used a dual RNA-Seq approach, which allowed us to gain insight into the gene expression of both the host and the pathogen simultaneously, and we observed differences in P. destructans gene expression that suggest host-pathogen interactions that might determine WNS progression. More recently we compared transcriptome-wide changes in gene expression levels in P. destructans grown on and actively infecting the wing of a bat (infecting pathogen) with P. destructans grown in culture (free …

Beautiful Minds : Exploring The Healing Potentional Of Self-Refexive Art In Facing A Campus Mental Health Crisis, Molly Chapman Rossi

Honors Theses

This interdisciplinary study of mental health seeks to do three things:

1. Identify and investigate the issue of mental health among students within the University of Richmond campus community, through both statistical and ethnographic data,

2. Apply trauma theory to redefine the crisis as a community trauma with unique aspects, and

3. Make a case for hope by proposing a plan that uses self-reflexive art, specifically theatre, to address the individualized community trauma and second-wave trauma.

I explicate new theories in this work, among them the notions of “individualized community trauma,” “second-wave trauma,” and “traumatic fusion.” Another critical concept is …

Impact Of Asean : China Free Trade Area On Trade Flows, Son Tung Nguyen

Honors Theses

This paper estimates the impact of the ASEAN-China Free Trade Agreement on the trade flows between China and the ASEAN countries. A gravity model with FTA specification is used to estimate the treatment effect of ACFTA. Since there are other unobserved variables that correlate with both the trade flows between China–ASEAN and the decision to form ACFTA, a cross-sectional OLS regression runs the risk of having endogeneity bias due to omitted variables. Therefore, this paper applies a panel regression approach with time and country fixed effects as the main method of estimation. The hypothesis is that ACFTA will increase trade …

The Effects Of Financial Leverage On The Output Decision Of An Exploration And Production Company, Michael Levine

Honors Theses

I examine companies focused on the exploration, production and exploitation of oil and gas assets to test whether there is a significant relationship between a firm’s debt burden and its production decision. I am most interested in debt’s effect on a firm’s price elasticity of supply as this would allow me to conclude how a highly levered firm would react to changes in price relative to other firms. I use data from 81 publicly traded exploration and production companies with varying degrees of leverage over the last ten years. This time frame captures two price cycles for the oil and …

How Does One Child Policy Influence Chinese Household Saving Behavior, Yueyang Cao

Honors Theses

This paper investigates the influence the decline in the family size on household size through a Chinese family planning policy, the One-Child Policy (OCP). I find the evidence of the negative effect at the micro level using Chinese household survey data. I also study the aggregated effect using Chinese provincial level data. With the concern of endogeneity, I use a two-stage least square regression with financial punishments for having more than one child and share of population that were exempted from the restriction as instruments for the fertility variable. This regression shows a positive impact of the implementation of the …

Food Insecurity In Nepal : A Cross-Sectional Analysis From 75 Districts, Aarti Reddy

Honors Theses

There are a number of studies regarding food insecurity, but not many that investigate the simultaneous relationships between food insecurity and the measures of well-being (health, education and gender equality). This paper conducts a district-level cross-sectional analysis of the relationship between food insecurity and the measures of well-being in Nepal using an ordered probit model. Instrument variables are used in a two-stage analysis to address the problem of endogeneity. The study finds that health deprivation levels significantly affect levels of food insecurity in a district but education and gender literacy disparity are less significant. Addressing issues of endogeneity and multicolinearity …

Cameron-Liebler Line Classes And Partial Difference Sets, Uthaipon Tantipongipat

Honors Theses

The work consists of three parts. The first is a study of Cameron-Liebler line classes which receive much attention recently. We studied a new construction of infinite family of Cameron-Liebler line classes presented in the paper by Tao Feng, Koji Momihara, and Qing Xiang (rst introduced in 2014), and summarized our attempts to generalize this construction to discover any new Cameron-Liebler line classes or partial difference sets (PDSs) resulting from the Cameron-Liebler line classes. The second is our approach to finding PDS in non-elementary abelian groups. Our attempt eventually led to the same general construction of PDS presented in John …

Computational Studies Of Paradifluorobenzene Cations And Hydrogen Cyanide Molecule, John C. Rowe Iv

Honors Theses

Polycyclic aromatic hydrocarbons (PAHs) are hypothesized to comprise a significant portion of interstellar carbon identified from the Diffuse Interstellar Bands (DIBs). Gas phase cation-molecule reactions between compounds that previously existed as weakly bound species provides the best explanation for the emergence of PAHs in the interstellar medium (ISM). In this work, we use computational methods to characterize one of these weakly-bound systems. We discovered that intramolecular charge distribution (calculated using the Natural Population Analysis) dictate the complexes formed between a paradifluorobenzene cation and either one or two HCN molecules. Additionally, the relative stabilities of the complexes and the binding energies …

Breaking The Language Barrier : The Spanish Translation Of The Barriers To Access To Care Evaluation (Bace), Yosmary Rodriguez

Honors Theses

The Hispanic/Latino population in the United States has been identified as a high-risk group for mental health problems. Unfortunately, due to commonly reported factors such as lack of linguistically and culturally appropriate services, many fail to seek treatment. While growing research has focused on identifying and addressing the different barriers to accessing mental health care experienced by this community, there continues to be a lack of validated Spanish assessments to aid in the evaluation of these barriers. In hopes of overcoming this barrier, and working towards better quality of care for this growing population, this project translated the Barriers to …

An Examination Of The Cmb Large-Angle Suppression, Ellis Herman

Honors Theses

As shown by COBE­DMR and then by the Wilkinson Anisotropy Probe (WMAP), there exists an anomaly in the correlation function of the cosmic microwave background (CMB) radiation, namely that said correlation function is suppressed to zero on large angular scales. This observation conflicts with the prediction made by Lambda­CDM, the standard model of cosmology, indicating either necessary changes to the standard model or that our universe is a rare fluke within LCDM ­ such suppressions are seen in only about 0.3% of universes predicted by LCDM. To differentiate into which of these categories our universe falls, we have attempted to …

Characterization Of Catecholamine Receptors And Transporters In Murine Macrophages, Elizabeth Gonye

Honors Theses

Macrophages are a critical part of the immune response. When circulating monocytes move into tissues they differentiate int macrophages to mount the first line of defense against pathogens.

Nonexistence Of Nonquadratic Kerdock Sets In Six Variables, John Clikeman

Honors Theses

Kerdock sets are maximally sized sets of boolean functions such that the sum of any two functions in the set is bent. This paper modifies the methodology of a paper by Phelps (2015) to the problem of finding Kerdock sets in six variables containing non-quadratic elements. Using a computer search, we demonstrate that no Kerdock sets exist containing non-quadratic six- variable bent functions, and that the largest bent set containing such functions has size 8.

A Computational Study Of High Energy Density Materials And Their Detection Using Surface-Enhanced Raman Spectroscopy, Emily N. Hugo

Honors Theses

The purpose of this thesis is to theoretically predict the vibrational spectra of select high energy density materials (HEDMs) as well as some of their byproducts and to determine if using surface-enhanced Raman spectroscopy (SERS) could be a viable detection method for these compounds. Studying the vibrational patterns of these compounds will help in identifying them in the environment for remediation purposes. Because the byproducts are smaller and easier to model than the parent compounds, these were studied more in depth through analyzing their Infrared and Raman spectra. Ag2 was used to model the interactions between the Ag nanoparticles used …

The Effects Of Oral Probiotic Supplements On The Human Gut Microbiome, Erin Hudnall

Honors Theses

A diverse bacterial community makes up the human gut microbiome and is essential not only to digestion, but also to other physiological processes. This bacterial community is subject to change due to external factors including, but not limited to, age, diet, and lifestyle. This study observed the effects of oral probiotic supplements on this bacterial community. Fecal samples were collected from a single subject once each week during alternating two- to six-week cycles of taking and abstaining from the probiotic supplement. The samples were purified, the bacterial cells within lysed, and the enclosed DNA was collected. A portion of the …

Urbanization And Exclusion: Examining The Wages Of Migrant Workers In The Chinese Urban Labor Market, Evan Heitzmann

Honors Theses

This work is primarily an examination of the economic effects of the Hukou system on migrant workers who live in cities. By endeavoring to control for any differences in background and human capital, I will attempt to isolate any premium attached the possession of urban Hukou. What, if any, benefit or advantage do urban citizens have over rural migrant in cities? Will they be favorably treated and will migrants be discriminated against? These are all questions that my project seeks to answer through the construction of a linear regression model that estimates the wages of both urban and migrant workers. …

A Practical Guide To Chemical Process Optimization: Analysis Of A Styrene Plant, Fleur Phelps

Honors Theses

This report acts as a beginner's guide to chemical processes optimization. Performed universally, optimization merely entails improving an existing process, situation, device or system. For a chemical engineer, optimization typically aims to maximize potential economics of a chemical process by manipulating decision variables while staying within known constraints. In order to maximize the overall economics of a chemical process, individual equipment or stream conditions are examined. The chemical process is implemented in simulation software The optimization of individual components of the process may aim to maximize or minimize an outcome specific to that component, but still ultimately maximizes economic potential. …

Multidimensional Motion Capture Using Doppler Ultrasound, Forrest Nolan Gamble

Honors Theses

Ultrasonic waves are used to measure the velocity of a target object by measuring the Doppler shift of the reflected waves. In this work, ultrasonic Doppler Sonar (UDS) was used to measure the velocity of objects, including a pendulum and a battery on a turntable. The investigation focused on developing a method to measure motion in two and three dimensions, for applications in gait analysis and sports motion capture. By using multiple ultrasonic transducers and novel data processing techniques, the UDS captured motion in two and three dimensions. In order to test the accuracy of the velocity and position measurements, …

The Mockingjay Phenomena: A Study On The Position Of Young Adult Women In Dystopia, Hannah Hultman

Honors Theses

The purpose of this research is to explore the messages and impact of three young adult dystopian trilogies, The Hunger Games, Divergent and The Uglies. In particular, the role of the American female teenager in political, economic and social spheres is discussed through examining the three female teenaged protagonists of these novels. For comparative purposes, George Orwell's 1984 and Aldous Huxley's Brave New World function as counterpoints to the young adult novels; the analysis of these different novels will prove that young adult dystopian novels show young adult women that their choices and actions can be integral to their societies …

Read Me: The Emergence Of Female Voice In American Epistolary Fiction, Allison Melissa Ramsey

Honors Theses

The objective of the thesis was to study how the letter, as a narrative device provided by the epistolary genre, supplies unheard female characters with an avenue to speak when their worlds do not allow it. In the novels, the letters not only permit a female character to practice building a voice, but also provide a self-reflection and identification experience, which enables the woman to see where she is, rewrite her role, and control where she wants to go. Through reading Hannah Webster Foster's The Coquette, Alice Walker's The Color Purple, Lee Smith's Fair and Tender Ladies, and Maria Semple's …

Boredom And Psychological Time Perspective On Cognition, Alyssa Erin Invergo

Honors Theses

This study investigated psychological time with regards to a memory recognition task. The participants rated images on a 5-point scale of attractiveness. There were two different conditions, one having 40 male faces and the other containing 40 female faces. After they finished rating the faces, they made a retrospective time estimate of how long they thought they spent viewing the faces. Following this they took the Multidimensional State Boredom Scale (MSBS) to test what state of boredom they were currently experiencing. Finally they performed a memory recognition test. We noticed statistically significant differences between the two conditions based on target …

Design Of A Caustic Injection System In A Crude Distillation Unit, Andrew R. Cope

Honors Theses

Caustic Injection is a high-risk chemical process utilized in many refineries across the world to control overhead corrosion in the atmospheric distillation column of the Crude Distillation Unit. This thesis discusses the considerations that need to be accounted for in the design of a caustic injection system, as well as my own work at an internship where I was a member of a design team that worked to design a caustic injection system for a nearby refinery.