Physical Sciences and Mathematics Commons^™

The Role Of Uncertainty In Categorical Perception Utilizing Statistical Learning In Robots, Nathaniel V. Powell

Graduate College Dissertations and Theses

At the heart of statistical learning lies the concept of uncertainty.

Similarly, embodied agents such as robots

and animals must likewise address uncertainty, as sensation

is always only a partial reflection of reality. This

thesis addresses the role that uncertainty can play in

a central building block of intelligence: categorization.

Cognitive agents are able to perform tasks like categorical perception

through physical interaction (active categorical perception; ACP),

or passively at a distance (distal categorical perception; DCP).

It is possible that the former scaffolds the learning of

the latter. However, it is unclear whether DCP indeed scaffolds

ACP in humans and …

Modeling The Spatiotemporal Dynamics Of Cells In The Lung, Joshua Jeremy Pothen

Graduate College Dissertations and Theses

Multiple research problems related to the lung involve a need to take into account the spatiotemporal dynamics of the underlying component cells. Two such problems involve better understanding the nature of the allergic inflammatory response to explore what might cause chronic inflammatory diseases such as asthma, and determining the rules underlying stem cells used to engraft decellularized lung scaffolds in the hopes of growing new lungs for transplantation. For both problems, we model the systems computationally using agent-based modeling, a tool that enables us to capture these spatiotemporal dynamics by modeling any biological system as a collection of agents (cells) …

Erosion Rates In Subtropical, Rapidly Developing Countries: An Isotopic Approach To Measuring Background Rates Of Erosion In Brazil And China, Veronica Sosa-Gonzalez

Graduate College Dissertations and Theses

Erosion, a surface process, can be quantified over long-term (assumed to be the natural erosion rate of the landscape) and contemporary (modern) timeframes. My research used the rare cosmogenic isotope 10Be in sand and cobbles collected from rivers in southeastern Brazil (Santa Catarina and Rio de Janeiro states) and southwestern China (Yunnan province) to quantify long-term, background rates of erosion and sediment supply. These measurements will also increase number of such measurements in tropical and subtropical climates. I assessed the relationship between landscape parameters (topographic and climatic) and background erosion rates in order to understand factors related to erosion.

My …

Renewable Energy Transition: Dynamic Systems Analysis, Policy Scenarios, And Trade-Offs For The State Of Vermont, Christopher Ernest Clement

Graduate College Dissertations and Theses

There is broad consensus that a transition to renewable energy and a low-carbon economy is crucial for future development and prosperity, yet there are differing perspectives on how such a transition should be achieved. The overarching goal of this dissertation, which is comprised of three interrelated studies, is to analyze and compare energy futures scenarios to achieve a renewable energy transition and low-carbon economy in the State of Vermont. In the first study, an analysis is presented of the role of energy pricing regimes and economic policy in the context of pursuing a renewable energy transition in the State of …

Ecological Dynamics In Compost-Amended Soils And The Resulting Effects On Escherichia Coli Survival, Anya Cutler

Graduate College Dissertations and Theses

Escherichia coli (E. coli) are common and typically innocuous copiotrophic bacteria found in the mammalian gut microbiome. However, over the past 30 years, pathogenic E. coli have been responsible for several outbreaks of foodborne illness linked to contaminated produce. The introduction of Escherichia coli to an agricultural soil, via contaminated water, compost, or raw manure, exposes the bacterium to a medley of ecological forces not found in a mammalian gut environment. This study assesses a variety of abiotic and biotic soil factors that influence the ability of an "invasive" copiotrophic coliform bacterium to survive in compost-amended agricultural soil. The study …

Evolving Spatially Aggregated Features For Regional Modeling And Its Application To Satellite Imagery, Sam Kriegman

Graduate College Dissertations and Theses

Satellite imagery and remote sensing provide explanatory variables at relatively high resolutions for modeling geospatial phenomena, yet regional summaries are often desirable for analysis and actionable insight. In this paper, we propose a novel method of inducing spatial aggregations as a component of the statistical learning process, yielding regional model features whose construction is driven by model prediction performance rather than prior assumptions. Our results demonstrate that Genetic Programming is particularly well suited to this type of feature construction because it can automatically synthesize appropriate aggregations, as well as better incorporate them into predictive models compared to other regression methods …

Factors Influencing Mode Choice For Intercity Travel From Northern New England To Major Northeastern Cities, Sean Patrick Neely

Graduate College Dissertations and Theses

Long-distance and intercity travel generally make up a small portion of the total number of trips taken by an individual, while representing a large portion of aggregate distance traveled on the transportation system. While some research exists on intercity travel behavior between large metropolitan centers, this thesis addresses a need for more research on travel behavior between non-metropolitan areas and large metropolitan centers. This research specifically considers travel from home locations in northern New England, going to Boston, New York City, Philadelphia, and Washington, DC. These trips are important for quality of life, multimodal planning, and rural economies. This research …

Enabling Machine Science Through Distributed Human Computing, Mark David Wagy

Graduate College Dissertations and Theses

Distributed human computing techniques have been shown to be effective ways of accessing the problem-solving capabilities of a large group of anonymous individuals over the World Wide Web. They have been successfully applied to such diverse domains as computer security, biology and astronomy. The success of distributed human computing in various domains suggests that it can be utilized for complex collaborative problem solving. Thus it could be used for "machine science": utilizing machines to facilitate the vetting of disparate human hypotheses for solving scientific and engineering problems.

In this thesis, we show that machine science is possible through distributed human …

The Role Of Transportation In Expanding The Democratic Ideal Of National Parks, Xiao Xiao

Graduate College Dissertations and Theses

National parks have famously been called "America's best idea" and preserve the nation's natural and cultural resources for the enjoyment of all. One of the current working priorities of the National Park Service (NPS) is enhancing the relevancy and engagement of the national parks with diverse audiences, especially for underserved groups. To address this priority, transportation is needed to provide access to national parks, but transportation may not be equally accessible to all groups in society. Understanding the effects of transportation on visitation to the national parks by racial/ethnic groups is essential for the NPS to improve the accessibility of …

Methods For The Spatial Modeling Of Forest Carbon In The Northern Forest, Alison Adams

Graduate College Dissertations and Theses

The ability to accurately assess forest carbon storage is critical to understanding global carbon cycles and the effects of changes in land cover on ecological processes. However, existing methods for calculating carbon storage do not explicitly account for differences in carbon stored by different species of trees. Those methods that do reflect some of this variability, such as remotely-sensing canopy structure to estimate biomass, can be resource-intensive and difficult to reproduce over past or future time steps in order to assess change. I examined the accuracy of several carbon mapping approaches to understand how specificity of forest type classification (for …

Quantifying Cultural Changes Through A Half-Century Of Song Lyrics And Books, Robert Bruce Woodward Iii

Graduate College Dissertations and Theses

Music is an ever-changing cultural reflection. It is deeply integrated into our society, ubiquitous

in movies, television shows, restaurants, sport venues, churches and a plethora of

other places. This thesis proposes that we consider the lyrics in popular music, as determined

by Billboards Hot 100 chart, as a natural medium to analyze the changes in culture

over the past half-century. Using this collection of lyrics, we analyze the change in relative

frequency of individual words over time, and compare to works of literature. Furthermore,

we use the ranking in the Top 100 as a metric with which to explore the …

Impacts Of Forest Disturbance On Small Mammal Distribution, Allyson Lenora Degrassi

Graduate College Dissertations and Theses

Natural habitat in the eastern United States has diminished over the past century because of the effects of invasive species. Both plant and animal invaders can alter habitat structure and may decrease survival of native species. The degree to which an invasive species alters ecosystem function depends on the functional characteristics of affected species and the resulting cascading effects. The loss of important native species, such as foundation species, can potentially influence the structure and distribution of animal communities because of the foundation species' unique ecosystem roles. The foundation species concept is relatively new to the terrestrial ecology and the …

The Impacts Of Climate Change On Precipitation And Hydrology In The Northeastern United States, Justin Guilbert

Graduate College Dissertations and Theses

Shifting climatic regimes can increase or decrease the frequency of extreme hydrologic events (e.g., high and low streamflows) causing large societal and environmental impacts. The impacts are numerous and include human health and safety, the destruction of infrastructure, water resources, nutrient and sediment transport, and within stream ecological health. It is unclear how the hydrology of a given region will shift in response to climate change. This is especially the case in areas that are seasonally snow covered as the interplay of changing temperature, precipitation, and resulting snowpack can lead to an increased risk of flood or drought.

This research …

Constituent Loads And Trends In The Upper Illinois River Watershed And Upper White River Basin, Erin E. Scott, Zach P. Simpson, Brian E. Haggard

Arkansas Water Resources Center Technical Reports

Water chemistry can greatly influence the quality of surface waters and affect the ability for streams and rivers to meet their designated use(s). In Arkansas, many streams and rivers were placed on the 2008 303(d) list of impaired water bodies due to excess levels of nutrients, chlorides, sulfates, and sediments (ADEQ, 2008). These constituents continue to be listed as the potential cause for water‐quality impairments through the most recent draft 303(d) list (ADEQ, 2014). The Arkansas Non‐Point Source (NPS) Management Program wants to reduce poll‐ utant loading from the landscape and improve water quality, where funding for projects is targeted …

Development Of A Samarium Based Allylic Benzoate Elimination/Isomerization: Application To A Total Synthesis Of Honokiol, Alicia M. Wright

WWU Graduate School Collection

We have developed a new samarium diiodide-mediated elimination/isomerization reaction of benzoyl esters, capable of delivering olefinic products with high yield and selectivity depending on substrate structure and the additives used. The ability to selectively synthesize terminal, non-conjugated alkene substituents inspired us to use these optimized conditions in order to complete the total synthesis of the natural product, honokiol. Honokiol is a biaryl natural product isolated from magnolia trees that displays desirable oncological properties as evidenced by several biological studies in recent years. We found that our initially proposed pathway for completing the synthesis of honokiol was not a feasible route …

Fluvial Incision, Upper Plate Faulting, And Short-Term Deformation In The Southern Olympic Mountains Of Washington State, Jaime Delano

WWU Graduate School Collection

Understanding topographic development in subduction zone forearcs requires comparison of deformation at short and long-term time intervals. We focus here on geomorphic records of uplift and incision in the Cascadia forearc of Washington State for comparison with short-term deformation driven by subduction zone coupling. We use surficial geologic mapping, optically stimulated luminescence dating, and surveyed terrace strath elevations to document fluvial incision and fault slip rates in the Wynoochee River valley in the southern Olympic Mountains. Results from 14 optically stimulated luminescence samples yield fluvial terrace age groupings of ~7-12 ka, ~14-18 ka, ~30-45 ka, and ~50-60 ka, which likely …

Effect Of Polymer Concentration, Rotational Speed, And Solvent Mixture On Fiber Formation Using Forcespinning, Nancy Obregon, Victor Agubra, Madhab Pokhrel, Howard Campos, David Flores, David De La Garza, Yuanbing Mao, Javier Macossay, Mataz Alcoutlabi

Physics and Astronomy Faculty Publications and Presentations

Polycaprolactone (PCL) fibers were produced using Forcespinning® (FS). The effects of PCL concentration, solvent mixture, and the spinneret rotational speed on fiber formation were evaluated. The concentration of the polymer in the solvents was a critical determinant of the solution viscosity. Lower PCL concentrations resulted in low solution viscosities with a correspondingly low fiber production rate with many beads. Bead-free fibers with high production rate and uniform fiber diameter distribution were obtained from the optimum PCL concentration (i.e., 12.5 wt%) with tetrahydrofuran (THF) as the solvent. The addition of N, N-dimethylformamide (DMF) to the THF solvent promoted the gradual formation …

Improved Analysis Of Gw150914 Using A Fully Spin-Precessing Waveform Model, B. P. Abbott, R. Abbott, T. D. Abbott, M. R. Abernathy, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, B. Allen, A. Allocca, P. A. Altin, S. B. Anderson, W. G. Anderson, K. Arai, M. C. Araya, C. C. Arceneaux, J. S. Areeda, N. Arnaud, K. G. Arun

Physics and Astronomy Faculty Publications and Presentations

This paper presents updated estimates of source parameters for GW150914, a binary black-hole coalescence event detected by the Laser Interferometer Gravitational-wave Observatory (LIGO) in 2015 [Abbott et al. Phys. Rev. Lett. 116, 061102 (2016).]. Abbott et al. [Phys. Rev. Lett. 116, 241102 (2016).] presented parameter estimation of the source using a 13-dimensional, phenomenological precessing-spin model (precessing IMRPhenom) and an 11-dimensional nonprecessing effective-one body (EOB) model calibrated to numerical-relativity simulations, which forces spin alignment (nonprecessing EOBNR). Here, we present new results that include a 15-dimensional precessingspin waveform model (precessing EOBNR) developed within the EOB formalism. We find good agreement with the …

No Amygdala, No Worries, Ilana Ascher

The Synapse: Intercollegiate science magazine

No abstract provided.

Bpa Here, There, Everywhere, Jane Sedlak

The Synapse: Intercollegiate science magazine

No abstract provided.

Honors Research: Featured Research By Oberlin College Students, Lisa Learman, Stephanie Atwood, Ashley Ratigan

The Synapse: Intercollegiate science magazine

No abstract provided.

Beyond The Event Horizon: The Mystery Of Supermassive Black Holes, Jacob Turner

The Synapse: Intercollegiate science magazine

No abstract provided.

Issue 10

The Synapse: Intercollegiate science magazine

No abstract provided.

Moonshot For Cancer: The Language Of Cancer Policy, Nate Bohm-Levine

The Synapse: Intercollegiate science magazine

No abstract provided.

The Humanity Of Cancer: Recognizing, Understanding And Fighting The Disease Through History, Oluwadamilare Ogunjimi

The Synapse: Intercollegiate science magazine

No abstract provided.

The Science Of Cute: What Makes Us Say "Aww!", Allison Murphy

The Synapse: Intercollegiate science magazine

No abstract provided.

Sifting Throught The Sediments Of Time: Using Thermonuclear Events To Measure Environmental Erosion Rates, Monica Dix

The Synapse: Intercollegiate science magazine

No abstract provided.

The Psychology Of Mental Illness Stigma: Stereotypes And Solutions, Daphnis Bream

The Synapse: Intercollegiate science magazine

No abstract provided.

Crossword Corner, Rachel Dan

The Synapse: Intercollegiate science magazine

No abstract provided.

The Effect Of Ignoring Statistical Interactions In Regression Analyses Conducted In Epidemiologic Studies: An Example With Survival Analysis Using Cox Proportional Hazards Regression Model, Kristina Vatcheva, Joseph B. Mccormick, Mohammad H. Rahbar

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

Objective: To demonstrate the adverse impact of ignoring statistical interactions in regression models used in epidemiologic studies.

Study design and setting: Based on different scenarios that involved known values for coefficient of the interaction term in Cox regression models we generated 1000 samples of size 600 each. The simulated samples and a real life data set from the Cameron County Hispanic Cohort were used to evaluate the effect of ignoring statistical interactions in these models.

Results: Compared to correctly specified Cox regression models with interaction terms, misspecified models without interaction terms resulted in up to 8.95 fold bias in estimated …