Digital Commons Network^™

Improving A Wireless Localization System Via Machine Learning Techniques And Security Protocols, Zachary Yorio

Masters Theses, 2020-current

The recent advancements made in Internet of Things (IoT) devices have brought forth new opportunities for technologies and systems to be integrated into our everyday life. In this work, we investigate how edge nodes can effectively utilize 802.11 wireless beacon frames being broadcast from pre-existing access points in a building to achieve room-level localization. We explain the needed hardware and software for this system and demonstrate a proof of concept with experimental data analysis. Improvements to localization accuracy are shown via machine learning by implementing the random forest algorithm. Using this algorithm, historical data can train the model and make …

An Analysis Of Technological Components In Relation To Privacy In A Smart City, Kayla Rutherford, Ben Lands, A. J. Stiles

James Madison Undergraduate Research Journal (JMURJ)

A smart city is an interconnection of technological components that store, process, and wirelessly transmit information to enhance the efficiency of applications and the individuals who use those applications. Over the course of the 21st century, it is expected that an overwhelming majority of the world’s population will live in urban areas and that the number of wireless devices will increase. The resulting increase in wireless data transmission means that the privacy of data will be increasingly at risk. This paper uses a holistic problem-solving approach to evaluate the security challenges posed by the technological components that make up a …

A Pilot Study On The Impact Of Teaching Assistant Led Cs1 Study Sessions Using Peer Instruction, Megan E. Gilbert

Senior Honors Projects, 2020-current

James Madison University’s Computer Science program strives to be a student-centered learning environment with a focus on creating a community for undergraduate success. National data reveals computer science has the lowest student retention rate compared to other STEM majors. The National Center for Women and Information Technology (NCWIT) has compiled a list of ways to retain students in Computer Science. In particular, NCWIT calls for collaboration indicate that “a sense of belonging, or a feeling of fit, is important for supporting student interest and persistence.” One aspect of creating community is the department’s longstanding commitment to provide undergraduate teaching assistants …

From Branches To Fibers - Investigating F-Actin Networks With Biochemistry And Mathematical Modeling, Melissa A. Riddle

Senior Honors Projects, 2020-current

F-actin networks have different structures throughout the cell depending on their location or mechanical role. For example, at the leading edge of a migrating cell, F-actin is organized in a region called the lamellipodia as a branched network responsible for pushing the membrane outwards. Behind the lamellipodia is a lamellar actin network where focal adhesions and stress fibers originate, and then within the cell cortex, actin is arranged in a gel-like network. Stress fibers are an important organization of F-actin and how they arise from either the branched lamellipodia network or the gel-like cortex network is poorly understood. Our approach …

Can Auxiliary Information Improve Rasch Estimation At Small Sample Sizes?, Derek Sauder

Dissertations, 2020-current

The Rasch model is commonly used to calibrate multiple choice items. However, the sample sizes needed to estimate the Rasch model can be difficult to attain (e.g., consider a small testing company trying to pretest new items). With small sample sizes, auxiliary information besides the item responses may improve estimation of the item parameters. The purpose of this study was to determine if incorporating item property information (i.e., characteristics of the items related to item difficulty) in a random effects linear logistic test model (RE-LLTM) would improve estimation of item difficulty. A simulation study was conducted that varied sample size, …

Curvature In Compressed Thin Cylindrical Shells Approaching The Isometric Limit, Nicole Voce

Senior Honors Projects, 2020-current

The ability to manipulate surface elastic instabilities finds many applications in engineering smart interfaces, e.g. in fluid-structure interaction and micro-fabrication. We study the buckling of a thin cylindrical shell constrained to slide onto an inner non-deformable pipe. Our goal is to characterize the relationship between the shell thickness and the localization of stresses by using curvature measurements. First, we induce surface buckling by immobilizing one end of the shell and applying force to the other end. Then, we obtain a virtual reconstruction of the surface from 3D optical scanning and compute the Gaussian curvature for every point on the mesh. …

An Analysis And Comparison Of Knot Polynomials, Hannah Steinhauer

Senior Honors Projects, 2020-current

Knot polynomials are polynomial equations that are assigned to knot projections based on the mathematical properties of the knots. They are also invariants, or properties of knots that do not change under ambient isotopy. In other words, given an invariant α for a knot K, α is the same for any projection of K. We will define these knot polynomials and explain the processes by which one finds them for a given knot projection. We will also compare the relative usefulness of these polynomials.

Refining Interpretations Of A Deglacial Record In Gulf Of Mexico Marine Sediment Cores Using Foraminifera C-14 Dates And Multi-Proxy Sediment Analyses, Lindsey R. Monito

Senior Honors Projects, 2020-current

The upper fourteen sections of three cores recovered from the International Marine Past Global Changes Study (IMAGES) VIII/Paleoceanography of the Atlantic and Geochemistry (PAGE) 127 expedition of 2002, are stratigraphic records of the climate and provenance variations that influenced sediment deposition in the Gulf of Mexico during the Pleistocene and Holocene. Though originally cored by the USGS for gas hydrate investigations, cores MD02-2535, MD02-2555, and MD02-2560 have been repurposed for undergraduate course-based paleoclimate research at JMU. Shipboard interpretations of the color reflectance data for these cores suggested that two dark stratigraphic intervals present in all of the cores were regional …

A Novel Approach To Updating Municipal Tax Parcel Impervious Surface Calculations, Patrick D. Muradaz

Senior Honors Projects, 2020-current

Accurate impervious surface calculations are important to many municipalities due to the high volumes of surface rainwater runoff caused by high impervious surface density. Municipalities must deal with this runoff through the establishment and maintenance of drainage facilities. To help offset the added cost of these facilities, many municipalities impose taxes and fees on privately owned impervious surfaces such as homes, driveways, and patios. Currently, in order for a city like Harrisonburg to calculate tax parcel impervious surface density, aerial images must be manually digitized or mapped using computer-based classification techniques using predictive models. These methods of impervious surface calculations …

Detecting Credit Card Fraud: An Analysis Of Fraud Detection Techniques, William Lovo

Senior Honors Projects, 2020-current

Advancements in the modern age have brought many conveniences, one of those being credit cards. Providing an individual the ability to hold their entire purchasing power in the form of pocket-sized plastic cards have made credit cards the preferred method to complete financial transactions. However, these systems are not infallible and may provide criminals and other bad actors the opportunity to abuse them. Financial institutions and their customers lose billions of dollars every year to credit card fraud. To combat this issue, fraud detection systems are deployed to discover fraudulent activity after they have occurred. Such systems rely on advanced …

Lightning Activity In The Continental United States On An Enso Time Scale, 2002-2015, Tyler M. Gingrich

Senior Honors Projects, 2020-current

This investigation examined the frequency and spatial pattern of lightning in the continental United States from 2002 to 2015. Before analysis, flashes were grouped based on their El Niño Southern Oscillation (ENSO) phase and Spatial Synoptic Classification (SSC) type for the winter season (December, January, and February). The purpose of this study is to better understand the relationship between planetary teleconnections, synoptic scale air masses, and micro scale phenomena, specifically lightning, in the continental United States. Evidence suggests ENSO cold phase flashes tend to have a lower frequency in number of flashes and flash days, as well as a northward …

A Multi-Input Deep Learning Model For C/C++ Source Code Attribution, Richard J. Tindell Ii

Masters Theses, 2020-current

Code stylometry is applying analysis techniques to a collection of source code or binaries to determine variations in style. The variations extracted are often used to identify the author of the text or to differentiate one piece from another.

In this research, we were able to create a multi-input deep learning model that could accurately categorize and group code from multiple projects. The deep learning model took as input word-based tokenization for code comments, character-based tokenization for the source code text, and the metadata features described by A. Caliskan-Islam et al. Using these three inputs, we were able to achieve …

Modeling Species Distribution And Habitat Suitability Of American Ginseng (Panax Quinquefolius) In Virginia, Jacob D. J. Peters

Masters Theses, 2020-current

American ginseng (Panax quinquefolius) is a well-known and sought-after medicinal plant native to North America that is facing increased threat of extinction due to overharvesting, herbivory, and habitat loss. Species distribution and habitat suitability models may be valuable to landowners interested in sustainable harvest or to institutions interested in the conservation and restoration of the species. With unequal sampling efforts across a region of interest, it is likely that some locations with appropriate habitat may be misrepresented in model predictions. This study refined a state-derived species distribution model for ginseng through increased sampling effort across the Cumberland Plateau …

Propensity Score Matching And Generalized Boosted Modeling In The Context Of Model Misspecification: A Simulation Study, Briana G. Craig

Masters Theses, 2020-current

In the absence of random assignment, researchers must consider the impact of selection bias – pre-existing covariate differences between groups due to differences among those entering into treatment and those otherwise unable to participate. Propensity score matching (PSM) and generalized boosted modeling (GBM) are two quasi-experimental pre-processing methods that strive to reduce the impact of selection bias before analyzing a treatment effect. PSM and GBM both examine a treatment and comparison group and either match or weight members of those groups to create new, balanced groups. The new, balanced groups theoretically can then be used as a proxy for the …

Generating Acoustic Projections Using 3d Models, Jake A. Brazelton

Senior Honors Projects, 2020-current

Raytracing is used in commercial graphics engines most commonly for lighting effects, but it also has many uses when it comes to acoustic simulation. Adopted directly from these computer graphics programs, the formulas presented herein enable the visualization of acoustic intensity levels throughout a 3D space using Python 3 and the OpenGL library. In addition to visualization, they also provide the ability to calculate the reverberation time and critical distance of an enclosed space in relation to its size and material makeup. The described application bundles all of these components together in a Qt5 application that allows users to view …

Towards Natural Language Understanding In Text-Based Games, Anthony Snarr

Senior Honors Projects, 2020-current

Text-based games are a very promising space for language-focused machine learning. Within them are huge hurdles in machine learning, like long-term planning and memory, interpretation and generation of natural language, unpredictability, and more. One problem to consider in the realm of natural language interpretation is how to train a machine learning model to understand a text-based game’s objective. This work considers treating this issue like a machine translation problem, where a detailed objective or list of instructions is given as input, and output is a predicted list of actions. This work also explores how a supervised learning system might learn …

Splitting Up A Complex Mess: The Effectiveness Of Statistical Analysis On Delimiting Species Complexes, Sara N. Schoen

Masters Theses, 2020-current

Recent studies have highlighted a need for more refined tools in species delimitation. This is especially true when considering diversity within species complexes, where members are morphologically similar and traditional tools have thus far failed to provide clearly defined boundaries between species. This project seeks to refine our traditional tools of species delimitation and apply new tools to the challenges created by species complexes. The focus organisms of this study are the anurans of the Limnonectes kuhlii complex. This species complex comprises more than 25 species of stream frogs from Southeast Asia. Traditionally, morphometrics (particularly linear measures) has been the …

Antibacterial Properties Of Novel Amphiphiles, Ariana Simeone

Masters Theses, 2020-current

Hospital acquired infections, particularly antibiotic resistant infections, are a growing concern due to their infection and mortality rate, as well as their growing economic burden, and it has been estimated that by the year 2050 the associated mortality rate will be around 10 million deaths per year. A solution to this is better means of prevention, and amphiphiles, compounds with at least one hydrophilic head group and at least one hydrophobic tail, are promising candidates for stopping the spread of infectious bacteria. Novel amphiphiles with two bipyridinium head groups, separated by a hydrophobic carbon spacer of varying lengths, and each …

Mitigating Real-Time Relay Phishing Attacks Against Mobile Push Notification Based Two-Factor Authentication Systems, Casey Silver

Masters Theses, 2020-current

This paper explores how existing push notification based two-factor authentication systems are susceptible to real-time man-in-the-middle relay attacks and proposes a system for mitigating such attacks. A fully functional reference system of the proposed mitigation was built and compared to an existing push notification two-factor authentication system while undergoing a real-time man-in-the-middle relay attack. The reference systems used cloud infrastructure for hosting, an Apple iPhone as the notification receiver, and Apple’s push notification service to send notifications. A publicly available tool for conducting real-time man-in-the-middle relay attacks was used to conduct the attacks. The results of the tests were recorded …

Whitepaper: Understanding Land-Atmosphere Interactions Through Tower-Based Flux And Continuous Atmospheric Boundary Layer Measurements, Manuel Helbig, Tobias Gerken, E Beamesderfer, D D. Baldocchi, T Banerjee, S C. Biraud, N A. Brunsell, S P. Butterworth, W S. Chan, A R. Desai, J D. Fuentes, D Y. Hollinger, N Klijun, M Mauder, K A. Novick, J M. Perkins, C Rey-Sanchez, R L. Scott, B Seyednasrollah, P C. Stoy, R C. Sullivan, J Vilà-Guerau De Arellano, S Wharton, C Yi, A D. Richardson

Libraries

Executive summary

● Target audience: AmeriFlux community, AmeriFlux Science Steering Committee & Department of Energy (DOE) program managers [ARM/ASR (atmosphere), TES (surface), and SBR (subsurface)]

● Problem statement: The atmospheric boundary layer mediates the exchange of energy and matter between the land surface and the free troposphere integrating a range of physical, chemical, and biological processes. However, continuous atmospheric boundary layer observations at AmeriFlux sites are still scarce. How can adding measurements of the atmospheric boundary layer enhance the scientific value of the AmeriFlux network?

● Research opportunities: We highlight four key opportunities to integrate tower-based flux measurements with continuous, …