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Full-Text Articles in Physical Sciences and Mathematics

Evaluating The Efficiency Of Low-Cost Air Quality Sensors At A Suburban Field Site, Olivia Wuttke Jun 2024

Evaluating The Efficiency Of Low-Cost Air Quality Sensors At A Suburban Field Site, Olivia Wuttke

Undergraduate Theses, Capstones, and Recitals

Science surrounding the use of low-cost sensors (LCS) to monitor air quality is rapidly expanding to satisfy the need to fill in regional air quality data gaps. This project evaluated the suitability of two types of LCS: Modulair-PM and PurpleAir (SD and Flex models) as efficient means to measure airborne particulate matter. The study involved physical installation of nine co-located sensors at a suburban site in Denver, connectivity troubleshooting as necessary, and data analysis/modeling of data over multiple months (19 weeks). PM data was compared between individual sensors of the same type, as well as across the two different sensor …


Technology And Homelessness: How Website Design And Blockchain Technology Could Impact The Unhoused, Casey Pratt Jun 2024

Technology And Homelessness: How Website Design And Blockchain Technology Could Impact The Unhoused, Casey Pratt

Undergraduate Theses, Capstones, and Recitals

Although technology could be used to combat inequality, it is instead increasing it. This paper discusses how the unhoused population suffers at the hand of technological inequality despite being relatively offline. It presents theories on how this would change if we reapproached how technology is used to assist the unhoused. It suggests implementing blockchain as a resource as well as modifying the websites built to assist in accessing benefits. Employees at shelters are interviewed for this paper about their experiences with using digital resources to rehouse and restabilize the vulnerable. They are asked how the sites can be improved for …


Comparing The Preparation Of Youth Services Librarians To Their On-The-Ground Experiences: A Grounded Theory Study Incorporating Criticism And Connoisseurship, Anne Holland Jun 2024

Comparing The Preparation Of Youth Services Librarians To Their On-The-Ground Experiences: A Grounded Theory Study Incorporating Criticism And Connoisseurship, Anne Holland

Electronic Theses and Dissertations

The purpose of this study was to better understand the on-the-ground preparation of youth services librarians, in contrast to their professional training in Master’s of Library Science (MLIS) programs. Classic Grounded Theory was the predominant methodology for this qualitative study, and elements of Criticism and Connoisseurship were also utilized. Document review, interviews, and journaling activities with ten participants were the primary methods of data collection. Key findings from this dissertation include a grounded theory explaining the current state of preparation for youth services librarianship, and multiple avenues for further study.


Piloting A Drain Gauge As A Method Of Measuring Runoff From Ecoroofs In Portland, Trinity Perrin Jun 2024

Piloting A Drain Gauge As A Method Of Measuring Runoff From Ecoroofs In Portland, Trinity Perrin

University Honors Theses

The following paper will be exploring a pilot methodology of a drain gauge system I built that’s used to calculate stormwater runoff from ecoroofs in Portland, Oregon. The drain gauge is a less studied technique for measuring ecoroof runoff, but holds high potential for developing better monitoring and management of ecoroofs within the city of Portland. What separates this stormwater runoff capturing device apart from other stormwater runoff calculation techniques is its adaptable design and simple installation. The drain weir can be placed in any roof drain that an ecoroof has been installed simply by placing it into a roof …


Quantifying Resting-State Functional Connectivity In Critically Brain-Injured Patients: A Graph-Theoretical Approach With Fnirs, Ira Gupta Jun 2024

Quantifying Resting-State Functional Connectivity In Critically Brain-Injured Patients: A Graph-Theoretical Approach With Fnirs, Ira Gupta

Electronic Thesis and Dissertation Repository

Assessment of consciousness in behaviourally unresponsive patients with critical brain injuries continues to be a challenge. There remains a need for robust tools that can accurately characterize preserved cortical function and predict patient outcomes. In the present study, functional near-infrared spectroscopy is employed in conjunction with graph theory and machine learning to quantify resting-state functional connectivity in 16 acutely brain-injured patients and 23 healthy controls. Results revealed significant channel-level differences between the groups for three graph metrics, including degree, clustering coefficient, and local efficiency. Further investigation using machine learning algorithms revealed that these metrics can be used to distinguish between …


Cards With Class: Formalizing A Simplified Collectible Card Game, Dan Ha Jun 2024

Cards With Class: Formalizing A Simplified Collectible Card Game, Dan Ha

University Honors Theses

Collectible card games (CCGs) have been a wildly popular game genre since the release of Wizards of the Coast's Magic: The Gathering. These games revolve around their thousands of cards and the hundreds of thousands of interactions they can create with their many effects. For designers, it is an incredibly demanding task to ensure that every single card works properly and that each card's text unambiguously conveys its intended behavior in all cases. The task only grows more difficult over time as the number of cards in the game grows and card effects become more complex or experimental. If the …


Scale-Dependent Effects Of Urban Canopy Cover, Canopy Volume, And Impervious Surfaces On Near Surface Air Temperature In Portland, Or, Carson Ralls Jun 2024

Scale-Dependent Effects Of Urban Canopy Cover, Canopy Volume, And Impervious Surfaces On Near Surface Air Temperature In Portland, Or, Carson Ralls

Geography Masters Research Papers

Cities are significantly warmer than their surrounding rural environments. Known as the ‘urban heat island effect’, it can affect the health of urban residents and lead to increased energy use. Although this effect is extensively researched, less is known about how landscape characteristics within cities affect local temperature variation. With a warming climate and the need for heat mitigation strategies becoming more urgent, having a finer detailed understanding of the effects on temperature is critical to guide proper management policies. This study examined how tree canopy cover, canopy volume, and impervious surface cover affect daytime near surface air temperature, and …


Modeling Exciton Delocalization And Transport In Pdbd-T-2f With The Line-Dipole Improvement For Coupling Calculation, Brian Dvorak Jun 2024

Modeling Exciton Delocalization And Transport In Pdbd-T-2f With The Line-Dipole Improvement For Coupling Calculation, Brian Dvorak

College of Science and Health Theses and Dissertations

A non-atomistic representation of the conjugated polymer PDBD-T-2F was constructed to model exciton delocalization and transport in the material. A Hamiltonian was built in the site basis to model the energy transfer, using excitation energies calculated using density functional theory and inter-site through-space coupling values calculated with either density functional theory or the newly integrated line-dipole approximation. The Hamiltonian allowed calculation of the excitation energies available for each system, prediction of the absorption spectrum, and simulation of the dynamics of exciton transport. For realistic crystal sizes at room temperature, the model predicts a band gap at 1.9 eV with decreasing …


The Institutional Challenges Of A Quantified Self Study: An Attempt To Ascertain How Data Collected From A Mobile Device Can Be An Indicator Of Personal Mental Health Over Time, Julian Lazaras Jun 2024

The Institutional Challenges Of A Quantified Self Study: An Attempt To Ascertain How Data Collected From A Mobile Device Can Be An Indicator Of Personal Mental Health Over Time, Julian Lazaras

University Honors Theses

The adoption of an application of new technology always comes with a bias, this is never more true for the case of human behavioral analytics within higher education. While movements such as the quantified self movement make strides to reinterpret the realm of data analytics, psychology, and computer science, there are inevitably limitations to the adoption and application of such approaches within the standard realm of research. Herein is presented a case where an effort to evaluate the prospect of use of mobile phone data as secondary indicators of personal mental health through the lens of data analysis was put …


Federated Learning Based Autoencoder Ensemble System For Malware Detection On Internet Of Things Devices, Steven Edward Arroyo Jun 2024

Federated Learning Based Autoencoder Ensemble System For Malware Detection On Internet Of Things Devices, Steven Edward Arroyo

Theses and Dissertations

New technologies are being introduced at a rate faster than ever before and smaller in size. Due to the size of these devices, security is often difficult to implement. The existing solution is a firewall-segmented “IoT Network” that only limits the effect of these infected devices on other parts of the network. We propose a lightweight unsupervised hybrid-cloud ensemble anomaly detection system for malware detection. We perform transfer learning using a generalized model trained on multiple IoT device sources to learn network traffic on new devices with minimal computational resources. We further extend our proposed system to utilize federated learning …


Feasibility Of Oil Palm Agroforestry System: Evaluating The Application Of Oil Palm Ash For Enhancing Cherry Tomato (Solanum Lycopersicum. Var. Nancy Rz) Production Using Brackish Water., Ime Joseph Bassey Jun 2024

Feasibility Of Oil Palm Agroforestry System: Evaluating The Application Of Oil Palm Ash For Enhancing Cherry Tomato (Solanum Lycopersicum. Var. Nancy Rz) Production Using Brackish Water., Ime Joseph Bassey

Theses and Dissertations

Monoculture systems of oil palm production are ravaging the world’s tropical forests, causing deforestation and biodiversity loss, which contribute to climate change at an uncontrollable pace. Oil palm agroforestry systems (AFSs), one of the strategies of regenerative agriculture, have proven to reverse the unfavorable effects of the oil palm monoculture systems. A sustainable means of soil fertilization and irrigation must be explored to improve the feasibility of oil palm AFSs. This study evaluates the impact of the application of oil palm ash and brackish irrigation on cherry tomato production. The experiment was conducted in a hydroponic system using a 2*4 …


Intimacy Without The Chance Of Heartbreak For Richer, For Poorer, In Sickness & In Health, Cynthia Nguyen Jun 2024

Intimacy Without The Chance Of Heartbreak For Richer, For Poorer, In Sickness & In Health, Cynthia Nguyen

Honors Projects

The present study investigates the effect of the COVID-19 pandemic on the consumption of porn, shifts in the production of porn consumed between men and women, and the breakdown of any pattern in adult content via film, pictures, and audio. A quantitative approach was done by using R to analyze data pulled off of Pornhub, Reddit’s GoneWildAudio subreddit, and Archive of Our Own from 2018 to 2023. Statistical inference and modeling is used to attempt to find a pattern in the production of online porn across three mediums over several years before, during, and after the pandemic. Regardless of events …


On Limiting Distributions For Eigenvalue Spectra Of Sample Correlation Matrices From Heavy-Tailed Populations: Literature Review, Sachini Sandhareka Wijesundara Jun 2024

On Limiting Distributions For Eigenvalue Spectra Of Sample Correlation Matrices From Heavy-Tailed Populations: Literature Review, Sachini Sandhareka Wijesundara

Major Papers

This major paper offers an extensive review of literature concerning the limiting distributions for the eigenvalue spectrum of sample correlation matrices from a p-dimensional population, where both the dimension p and the sample size n grow to infinity. The study systematically categorizes the reviewed literature based on underlying assumptions regarding the data characteristics. Specifically, it examines several distinct cases: the independent and identically distributed (i.i.d) case with finite fourth moments, the i.i.d case with infinite fourth moments, the i.i.d case with infinite second moments, and scenarios where rows and columns of the data are linearly dependent. Additionally, the major paper …


Instructional Strategies That Support Student Achievement With The Eureka Algebra 1 Curriculum, Honnalora Hill Jun 2024

Instructional Strategies That Support Student Achievement With The Eureka Algebra 1 Curriculum, Honnalora Hill

Walden Dissertations and Doctoral Studies

Numerous states use research-based mathematics curricula as a teaching tool to enhance mathematics performance outcomes on state assessment scores. Despite implementation of the Eureka curriculum, students at the study site were still struggling to master Algebra 1 skills sufficiently to pass the Louisiana state exam. The aim of this basic qualitative study was to explore strategies teachers employed while implementing the Eureka curriculum to increase student achievement. The study was guided by Vygotsky’s zone of proximal development (ZPD) theoretical framework and involved semi-structured interviews with 12 participants who had been teaching Algebra 1 with the Eureka curriculum for at least …


The Robot On The Hill, James Ryan Jun 2024

The Robot On The Hill, James Ryan

College of Computing and Digital Media Dissertations

“The Robot on the Hill” is a rogue-like autobattler that procedurally models the state of the individual in the information age. The game abruptly transitions between diverse framings - a hill, a bedroom, a pond, a chessboard, the void - in order to highlight the disjointedness that is present in the informationalizing of self and reality. It dialogues with Byung Chul Han and Heidegger to portray what Han describes as a ‘narrative crisis’ in modernity and the devaluation of experience. When the value of experience diminishes and disintegrates, “all that is left is bare life, a kind of survival.” …


Leveraging Biological Mechanisms In Machine Learning, Kyle J. Rogers Jun 2024

Leveraging Biological Mechanisms In Machine Learning, Kyle J. Rogers

Theses and Dissertations

This thesis integrates biologically-inspired mechanisms into machine learning to develop novel tuning algorithms, gradient abstractions for depth-wise parallelism, and an original bias neuron design. We introduce neuromodulatory tuning, which uses neurotransmitter-inspired bias adjustments to enhance transfer learning in spiking and non-spiking neural networks, significantly reducing parameter usage while maintaining performance. Additionally, we propose a novel approach that decouples the backward pass of backpropagation using layer abstractions, inspired by feedback loops in biological systems, enabling depth-wise training parallelization. We further extend neuromodulatory tuning by designing spiking bias neurons that mimic dopamine neuron mechanisms, leading to the development of volumetric tuning. This …


Implementing Selective Signature Scanning To Optimize Malware Detection, Lucas Gray Wilbur Jun 2024

Implementing Selective Signature Scanning To Optimize Malware Detection, Lucas Gray Wilbur

Computer Science Senior Theses

Signature scanning is one of the oldest types of malware detection, and it remains an essential lightweight detection method for many antivirus programs. However, signature scanning has unavoidable limitations, including an inevitably increasing runtime as malware signature databases continually expand. In this paper, we discuss the current state of signature scanning, including usage of the open-source signature scanning tool YARA. We test Zemlyanaya et al’s assertion that scanning only the beginning and end of files can reduce the runtime cost of signature database expansion — while maintaining a high level of accuracy — and find it inaccurate in the case …


Curating Familiarity Within The Unfamiliar: Exploring Non-Native Mobile App Experiences To Create Cross-Cultural Design Frameworks, Hanna Hong Jun 2024

Curating Familiarity Within The Unfamiliar: Exploring Non-Native Mobile App Experiences To Create Cross-Cultural Design Frameworks, Hanna Hong

Computer Science Senior Theses

Global mobility and markets are expanding, and as a result, countries are becoming less and less monocultural. With multiple cultural affinity groups to cater towards, companies often will deploy different versions of a website or app based on the country a user is accessing it from. This strategy of catering to geographic location results in a lack of accommodation for people living within a culture that is different from their native one. In order to increase accessibility and equal ease-of-use for all audiences, designers should understand and work towards the needs of a multicultural user base. This study investigates how …


Land-Use Governance And Indigenous Engagement In Arctic Alaska And Norway: Successes, Current Gaps, And Paths Forward, Ningning Sun Jun 2024

Land-Use Governance And Indigenous Engagement In Arctic Alaska And Norway: Successes, Current Gaps, And Paths Forward, Ningning Sun

Environmental Studies Senior Theses

This study aims to analyze the land use governance structures and the role of Indigenous engagement in Alaska and Norway using a comparative approach, with special focus on successful practices, current gaps, and paths forward to achieve equitable governance. Extractive land uses, such as oil and gas extraction and the construction of wind farms, have mixed impacts on Indigenous communities and lead to social and legal issues such as land use conflict and environmental injustice. Previous research has studied land use governance in Arctic countries with regard to Indigenous Peoples, yet there is a lack of literature that spans Alaska …


An Economic Remodel: The Genesis Of Modern Corporate Sustainability, Caitlin R. Doak Jun 2024

An Economic Remodel: The Genesis Of Modern Corporate Sustainability, Caitlin R. Doak

Environmental Studies Senior Theses

My thesis aims to understand and analyze what is catalyzing the advancement of sustainability in corporate agendas. After my internship at Deloitte and four years of Dartmouth undergrad, I recognized some important themes emerging in the sustainability landscape. Sustainability is at the forefront of policy and stakeholder engagement right now. Shareholders, consumers, regulators, policy makers, are all putting pressure on CSuite executives to redefine materiality and increase transparency in order to properly understand sustainability-related risks and opportunities within companies. Climate and nature-related disclosures are becoming just as important as financial disclosures because companies are being evaluated holistically, and a company’s …


The Fight For Rice: Understanding How Monte Cristi Will Respond To Dr-Cafta And Climate Change, Scarlette G. Flores Jun 2024

The Fight For Rice: Understanding How Monte Cristi Will Respond To Dr-Cafta And Climate Change, Scarlette G. Flores

Environmental Studies Senior Theses

The Dominican Republic and Central American Free Trade Agreement, or DR-CAFTA, was signed on March 1, 2007 by the United States, the Dominican Republic and six other countries in Central America. The United States set specific tariff schedules to be phased in after twenty years for certain crops, one of which is rice. Rice is one of the most important crops in the Dominican Republic and produced in the northwestern province of Monte Cristi. This area is affected by climate change due to droughts and water shortages. In my research, I investigate how rice farmers and agrochemical companies, two important …


Evading Antivirus Detection By Abusing File Type Identification, Chavin Udomwongsa Jun 2024

Evading Antivirus Detection By Abusing File Type Identification, Chavin Udomwongsa

Computer Science Senior Theses

File type identification is a vital step in automated file processing, especially in the realm of malware detection. The challenges with file type identification and evasion techniques that take advantage of them were pointed out over a decade ago. We show that this remains the case: file type identification implementations are still fragile, especially for files with ambiguous file types. We present a novel antivirus bypass technique via crafted tar archives that evades all detection from VirusTotal and numerous antiviruses: BitDefender, F-Secure, Kaspersky, Panda Dome, Trend Micro, Quick Heal, IKARUS, Avira. These crafted files evade detection by tricking file type …


The Impact Of Maine’S Municipal Shellfish Management On Clam Harvester Motivation To Participate In Resource Conservation, Rachel Lohr Freer Jun 2024

The Impact Of Maine’S Municipal Shellfish Management On Clam Harvester Motivation To Participate In Resource Conservation, Rachel Lohr Freer

Environmental Studies Senior Theses

This study investigates how the resource management strategies implemented by Maine’s different Municipal Shellfish Conservation Committees influences the motivation held by shellfish harvesters’ to participate in resource conservation activities. As soft shell clam landings are declining across Maine due to increasing predation and climate-related stress, there seems to be a disconnect in harvesters’ willingness to support the conservation activities that Shellfish Conservation Committees make available to them. In efforts to improve participation, town leadership in select regions have started to mandate the completion of annual conservation hours requirements. The diversity of policy approaches enacted by towns provides the unique opportunity …


Conserving The Public Lands: Policy And Spatial Analysis Of A Bureau Of Land Management Conservation Leasing Mechanism, Isaiah M. Menning Jun 2024

Conserving The Public Lands: Policy And Spatial Analysis Of A Bureau Of Land Management Conservation Leasing Mechanism, Isaiah M. Menning

Environmental Studies Senior Theses

The Bureau of Land Management (BLM) is the largest land administrator in the United States, managing about 10% of U.S. lands, primarily in the Western states. The BLM manages under a multiple-use framework, issuing commercial authorizations for grazing, mining, oil and gas, and wind and solar on public lands, while also managing for ecosystem health. In April 2024, the agency finalized a rule that would create a conservation leasing mechanism to allow private, state, and tribal parties to lease BLM lands for restoration and mitigation purposes, which I investigate here. First, I find that while the conservation leasing mechanism does …


The Dartmouth Land Ethic: Synthesizing Environmental Ethical Beliefs In Hanover And Beyond, Conor M. Roemer Jun 2024

The Dartmouth Land Ethic: Synthesizing Environmental Ethical Beliefs In Hanover And Beyond, Conor M. Roemer

Environmental Studies Senior Theses

In this thesis, I seek to explore the nature of an environmental ethical paradigm at Dartmouth. In order to do so, I have chosen to begin with an examination of Aldo Leopold’s Land Ethic. This watershed essay has inspired many environmental ethical inquiries in the last eighty years. Leopold’s Land Ethic urged human beings to view the environment beyond what might be extracted for anthropogenic use and to see the land as a summation of everything that lies within it: not just the plants and animals, but the mountains, rocks, rivers, and soil as well. In turn, scores of philosophers …


Penney’S Game For Permutations, Yixin Lin Jun 2024

Penney’S Game For Permutations, Yixin Lin

Dartmouth College Ph.D Dissertations

We explore the permutation analog of Penney's game for coin flips. Two players, in order, each choose a permutation of length $k\ge3$. Then a sequence of independent random values from a continuous distribution is generated until the relative order of the last $k$ numbers matches one of the chosen permutations, declaring the player who selected that permutation as the winner.

We calculate the winning probabilities for all pairs of permutations of length $3$ and some pairs of length $4$, demonstrating the non-transitive property of this game, consistent with the original word version. Alternatively, we provide formulas for computing the winning …


Khovanov Homology And Legendrian Simple Knots, Ryan J. Maguire Jun 2024

Khovanov Homology And Legendrian Simple Knots, Ryan J. Maguire

Dartmouth College Ph.D Dissertations

The Jones polynomial and Khovanov homology are powerful invariants in knot theory. Their computations are known to be NP-Hard and it can be quite a challenge to directly compute either of them for a general knot. We develop explicit algorithms for the Jones polynomial and discuss the implementation of an algorithm for Khovanov homology. Using this we tabulate the invariants for millions of knots, generate statistics on them, and formulate conjectures for Legendrian and transversely simple knots.


On Pattern Avoidance And Dynamical Algebraic Combinatorics, Benjamin Adenbaum Jun 2024

On Pattern Avoidance And Dynamical Algebraic Combinatorics, Benjamin Adenbaum

Dartmouth College Ph.D Dissertations

Over the past decade since the term `dynamical algebraic combinatorics' was coined there has been a tremendous amount of activity in the field. Adding to that growing body of work this thesis hopes to be a step towards a broader study of pattern avoidance within dynamical algebraic combinatorics and helps initiate that by considering an action of rowmotion on 321-avoiding permutations. Additionally within we show the first known instance of piecewise-linear rowmotion periodicity for an infinite family of posets that does not follow from a more general birational result. Finally we show that the code of permutation restricted to permutations …


The Application Of Elastic Distance In Astrophysical Time Series, Xiyang Zhang Jun 2024

The Application Of Elastic Distance In Astrophysical Time Series, Xiyang Zhang

Electronic Thesis and Dissertation Repository

Elastic distances, e.g. dynamic time warping (DTW), evaluate the similarity between query and reference sequences by dynamic programming. The 1-Nearest-Neighbor predictor with DTW is one benchmark in time series classification. However, DTW is less efficient in astronomical time series because of ignorance of the information in time stamps and its dependence on the shape and magnitude between query and reference sequences. We apply two elastic distances which integrate the information in the time domain, time warp editing distance (TWED) and Skorohod distance, which is calculated by using Fre ́chet distance, to three astronomical datasets to compare with DTW and Euclidean …


Artificial Intelligence As The Next Front In The Class War, Christopher Hill Jun 2024

Artificial Intelligence As The Next Front In The Class War, Christopher Hill

Dissertations and Theses

For many years, artificial intelligence has been confined to the realm of science fiction, and while the technology has been in development, predicting the effects AI will have on our society has been a challenging endeavor. The release of ChatGPT in 2022, the subsequent mass adoption of the AI chatbot, and the response by other private firms in the field announced AI's permanent entrance into the public sphere. These recent strides made in the field of artificial intelligence reveal that the pace of technological development has outstripped the rate at which we are able to politically examine and understand these …