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Contextualizing Interpersonal Data Sharing In Smart Homes, Weijia He, Nathan Reitinger, Atheer Almogbil, Yi-Shyuan Chiang, Timothy J. Pierson, David Kotz Jul 2024

Contextualizing Interpersonal Data Sharing In Smart Homes, Weijia He, Nathan Reitinger, Atheer Almogbil, Yi-Shyuan Chiang, Timothy J. Pierson, David Kotz

Dartmouth Scholarship

A key feature of smart home devices is monitoring the environment and recording data. These devices provide security via motion-detection video alerts, cost-savings via thermostat usage history, and peace of mind via functions like auto-locking doors or water leak detectors. At the same time, the sharing of this information in interpersonal relationships---though necessary---is currently accomplished on an all-or-nothing basis. This can easily lead to oversharing in a multi-user environment. Although prior work has studied people's perceptions of information sharing with vendors or ISPs, the sharing of household data among users who interact personally is less well understood. Interpersonal situations make …


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.


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 …


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 …


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 …


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 …


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 …


Advances In Computational And Statistical Inverse Problems, Dylan Green Jun 2024

Advances In Computational And Statistical Inverse Problems, Dylan Green

Dartmouth College Ph.D Dissertations

Inverse problems are prevalent in many fields of science and engineering, such as signal processing and medical imaging. In such problems, indirect data are used to recover information regarding some unknown parameters of interest. When these problems fail to be well-posed, the original problems must be modified to include additional constraints or optimization terms, giving rise to so-called regularization techniques. Classical methods for solving inverse problems are often deterministic and focus on finding point estimates for the unknowns. Some newer methods approach the solving of inverse problems by instead casting them in a statistical framework, allowing for novel point estimate …


Impact Of Similarities In Gender And Physical Appearance Between User And Embodied Conversational Agents On Trustworthiness, Empathy, And Service Evaluation, Sookyoung Park Jun 2024

Impact Of Similarities In Gender And Physical Appearance Between User And Embodied Conversational Agents On Trustworthiness, Empathy, And Service Evaluation, Sookyoung Park

Dartmouth College Master’s Theses

Embodied conversational agents (ECAs) have significantly enhanced human-machine interactions and show considerable potential in various industries such as customer service, education, healthcare, entertainment, and finance [1, 2]. This study explores the impact of similarities in gender and physical appearance between ECAs and users on the perceptions of trustworthiness, empathy, and service evaluation within the context of counselor ECAs. We conducted a within-subject experiment (n=50), using a 2x2 factorial arrangement, that varied the gender and the physical appearance of four distinct AI avatars. Participants interacted with each avatar, completing a post-experiment survey and participating in semi-structured interviews. Our findings indicate that …


Embodied Visions: Interactive Installations That Reimagine Bodily Presence In Digital Imaging Apparatuses As Shadows, Yunzi Shi May 2024

Embodied Visions: Interactive Installations That Reimagine Bodily Presence In Digital Imaging Apparatuses As Shadows, Yunzi Shi

Dartmouth College Master’s Theses

Contextualized within a history of technological development, the evolution of imaging devices and technologies is accompanied by the abstraction of spatial relationships between the body of the observer, the apparatus, and physical reality, which leads to disembodying experiences for the observing subject. Compared with devices and interactive experiences, critical reflection on the epistemological impact of digital imaging devices has less priority in computational imaging and human-computer interaction research. Taking an artistic approach, this thesis describes Embodied Visions, an exhibition featuring three interactive installations exploring the technical infrastructure for imaging and reflecting on the (dis)embodied experiences in the digital age. …


Simulating Cross-Scale Solid-Fluid Interaction Phenomena, Jinyuan Liu May 2024

Simulating Cross-Scale Solid-Fluid Interaction Phenomena, Jinyuan Liu

Dartmouth College Ph.D Dissertations

Solid-fluid interactions are ubiquitous in nature, and accurate simulation methods are essential for realistic animation, industrial design, and engineering analysis. Com- pared to large-scale coupling phenomena, simulating fine-scale interactions poses extra challenges due to factors such as surface tension, material wettability, and geometric complexity. In this thesis, we pursue novel methodologies to accurately model in- terfacial dynamics between surface-tension fluids and codimensional solids, involving capillary interactions, controllable wettability, and robust contact behaviors. Our ini- tial approach involves developing a novel three-way coupling method, which utilizes a thin liquid membrane, modelled as a simplicial mesh, to facilitate accurate momen- tum transfer, …


Toward The Integration Of Behavioral Sensing And Artificial Intelligence, Subigya K. Nepal May 2024

Toward The Integration Of Behavioral Sensing And Artificial Intelligence, Subigya K. Nepal

Dartmouth College Ph.D Dissertations

The integration of behavioral sensing and Artificial Intelligence (AI) has increasingly proven invaluable across various domains, offering profound insights into human behavior, enhancing mental health monitoring, and optimizing workplace productivity. This thesis presents five pivotal studies that employ smartphone, wearable, and laptop-based sensing to explore and push the boundaries of what these technologies can achieve in real-world settings. This body of work explores the innovative and practical applications of AI and behavioral sensing to capture and analyze data for diverse purposes. The first part of the thesis comprises longitudinal studies on behavioral sensing, providing a detailed, long-term view of how …


Towards Scalable Autonomous Underwater Construction With Free-Floating Robots, Samuel Eric Lensgraf May 2024

Towards Scalable Autonomous Underwater Construction With Free-Floating Robots, Samuel Eric Lensgraf

Dartmouth College Ph.D Dissertations

This thesis presents the first free-floating autonomous underwater construction system. Our system built structures weighing up to 100Kg (75Kg in water). Our robot builds structures made of standard cinder blocks and custom designed interlocking cement blocks. It is the first construction robot that uses active buoyancy compensation to efficiently transport building materials. It is also the first construction robot that can reconfigure visual fiducial markers on a foundation during the construction process to expand its working area.

Underwater construction is a challenging problem for free-floating robots. Currents can buffet the robot, and visibility conditions can change. We focus on achieving …


3-D Reconstruction For Underwater Robots With A Monocular Camera And Lights, Monika Roznere May 2024

3-D Reconstruction For Underwater Robots With A Monocular Camera And Lights, Monika Roznere

Dartmouth College Ph.D Dissertations

Before a robot can act, it must perceive its environment. Though, this is not a simple task when considering the challenges in underwater domains -- poor visibility conditions, limited sensor configurations, and lack of readily accessible localization. Underwater robots have, nevertheless, improved dramatically with more extensive sensor and navigation equipment. Robot and sensor use have enabled us to explore all reaches of our oceans. On the other hand, these same robots are not easily accessible or transferable to many practical tasks, including fishery management, infrastructure maintenance, disaster response, site conservation, and ecological surveys. There is a growing need for robots …


Automated Cinematographer For Vr Viewing Experiences, Zihan Wu May 2024

Automated Cinematographer For Vr Viewing Experiences, Zihan Wu

Dartmouth College Master’s Theses

As the virtual reality (VR) industry continues to evolve, the question of how to effectively capture VR experiences for an audience remains a challenge. The predominant method of showcasing VR applications through first-person recordings lacks cinematic interest, failing to capture other viewpoints and the essence of the moment. Meanwhile, manually setting up cameras and editing videos requires technical expertise on behalf of the user. In this paper, we propose the use of machine learning (ML) to automatically select the most compelling predefined viewpoint in a VR environment, at any given moment. Our models, trained on actor motion and voice volume, …


Advancing Mobile Sensing In Dynamic Environments, Weichen Wang Apr 2024

Advancing Mobile Sensing In Dynamic Environments, Weichen Wang

Dartmouth College Ph.D Dissertations

This thesis presents a comprehensive exploration of enhancing mobile sensing capabilities to address various aspects of human behavior, mental health, personality, social functioning and beyond. We redesign the StudentLife app to improve its sensing efficiency and dependability, enabling support for multi-year-long studies. By adopting new app design, this study addresses the technical challenges of continuous sensing and enhances system robustness. The work is organized into several key studies that collectively aim to expand the scope of mobile sensing in diverse and complex environments.

The first study broadens the scope of mobile sensing to assess personality traits, exploring the potential of …


Terrestrial Exchange Of Atmospheric Metals: Insights From Fallout Radionuclides, Joshua D. Landis Apr 2024

Terrestrial Exchange Of Atmospheric Metals: Insights From Fallout Radionuclides, Joshua D. Landis

Dartmouth College Ph.D Dissertations

Forests mediate the exchange of gases and particulate matter (PM2.5 and PM10) between terrestrial ecosystems and the atmosphere over 30% of global land area. Because forest foliage efficiently absorbs PM with persistent pollutants including metals Pb and Hg, as well as CO2 and gaseous elemental mercury (GEM), this exchange profoundly influences the composition of the atmosphere as well as terrestrial biogeochemical cycles. The processes by which PM is absorbed remain enigmatic, however, due to the complexity of micrometeorological physics and submicron physical scale of the interaction. Here, measurements of fallout radionuclides (FRNs) beryllium-7 and lead-210, which are quintessential tracers …


Models Of Low Mass Stars As Physical Labratories, Emily M. Boudreaux Apr 2024

Models Of Low Mass Stars As Physical Labratories, Emily M. Boudreaux

Dartmouth College Ph.D Dissertations

Low mass stars account for approximately 70 percent of the stellar populations (Conroy & Van Dokkum, 2012); yet, due to their small sizes and cool temperatures they account for only a small fraction of the galaxies luminosity function (Laughlin et al., 1997). Moreover, due to the lack of laboratory conditions available to astronomy and astrophysics low mass stars can provide a rare controlled environment for calibrations of numerical models. Consequently, across multiple domains there has been significant interest in these key astronomical objects. In this thesis I present three projects which have further revealed properties of low mass stars and …


Design, Analysis, And Drop Assembly Of Interlocking Rigid Bodies, Amy K. Sniffen Apr 2024

Design, Analysis, And Drop Assembly Of Interlocking Rigid Bodies, Amy K. Sniffen

Dartmouth College Ph.D Dissertations

This work presents a system of interlocking blocks that can be used to build a wide variety of structures. The blocks slide together to form structures that interlock geometrically like a puzzle to form semi-permanent structures without the need for cement or friction lock. The blocks are designed to be easy to fabricate, assemble, and disassemble. Contributions of the block designs include a novel interlocking joint structure; the joints are wedge-shaped, allowing for error mitigation during assembly and allowing structures to be assembled without jamming even if there is manufacturing error. We introduce planar, 3D, and volumetric designs using these …


Methods, Analyses, And Applications Of Multilayer Temporal Link Prediction In Networks, Xie He Apr 2024

Methods, Analyses, And Applications Of Multilayer Temporal Link Prediction In Networks, Xie He

Dartmouth College Ph.D Dissertations

Many applications stem from the possibility of accurately predicting links in various types of networks. In this thesis, we present methods, analyses, and applications for static, temporal, and multilayer networks. The first part of this thesis demonstrates how static network features serve as efficient and accurate predictors for link prediction in temporal networks. It includes an ensemble learning method we developed and presents experimental results on 90 synthetic stochastic block models and 19 real-world datasets. The second part closely follows, showcasing 20 different sampling methods and their effects on nine different link prediction algorithms for 250 real-world networks across 6 …


On Adaptivity And Randomness For Streaming Algorithms, Manuel Stoeckl Apr 2024

On Adaptivity And Randomness For Streaming Algorithms, Manuel Stoeckl

Dartmouth College Ph.D Dissertations

A streaming algorithm has a limited amount of memory and reads a long sequence (data stream) of input elements, one by one, and computes an output depending on the input. Such algorithms may be used in an online fashion, producing a sequence of intermediate outputs corresponding to the prefixes of the data stream. Adversarially robust streaming algorithms are required to give correct outputs with a desired probability even when the data stream is adaptively generated by an adversary that can see all intermediate outputs of the algorithm. This thesis binds together research on a variety of problems related to the …


On Generating Bijections For Permutations And Inversion Sequences, Melanie J. Ferreri Apr 2024

On Generating Bijections For Permutations And Inversion Sequences, Melanie J. Ferreri

Dartmouth College Ph.D Dissertations

Given an algebraic proof of a combinatorial identity, we use recursive methods to construct a bijection demonstrating the identity.

Our first application centers around derangements and nonderangements. A derangement is a permutation with no fixed point, and a nonderangement is a permutation with at least one fixed point. There is a one-term recurrence for the number of derangements of n elements, and we describe a bijective proof of this recurrence which can be found using a recursive map. We then show the combinatorial interpretation of this bijection and how it compares with other known bijections, and show how this extends …


Automated Glacier Classification In High Mountain Asia Using Machine Learning And A Random Forest Classifier, Victoria Elizabeth Halvorson Apr 2024

Automated Glacier Classification In High Mountain Asia Using Machine Learning And A Random Forest Classifier, Victoria Elizabeth Halvorson

Dartmouth College Master’s Theses

High Mountain Asia (HMA) is home to the largest mass of glaciers and ice outside the north and south polar regions. HMA glaciers are projected to experience accelerated mass loss from higher greenhouse gas emissions through the end of the century. Many studies of glacier mass balance and mass loss in HMA obtain glacier area from the Randolph Glacier Inventory (RGI). However, the RGI is designed to show glacier area across the world that is accurate to the year 2000 and, as a result, is not an accurate representation of the current state of glacier area in HMA. Additionally, glacier …


Probing Central Spin Decoherence Dynamics Of Electronic Point Defects In Diamond And Silicon, Ethan Que Williams Feb 2024

Probing Central Spin Decoherence Dynamics Of Electronic Point Defects In Diamond And Silicon, Ethan Que Williams

Dartmouth College Ph.D Dissertations

Electron spins of point defects in diamond and silicon can exhibit long coherence times, making them attractive platforms for the physical implementation of qubits for quantum sensing and quantum computing. To realize these technologies, it is essential to understand the mechanisms that limit their coherence. Decoherence of these systems is well described by the central spin model, wherein the central electron spin weakly interacts with numerous electron and nuclear spins in its environment. The dynamics of the resultant dephasing can be probed with pulse electron paramagnetic resonance (pEPR) experiments.

Using a 2.5 GHz pEPR spectrometer built in-house, we performed multi-pulse …


The Shifting Landscape Of Adolescent Wellness In Boarding Schools: Can Time Spent Off Screens And Outdoors Improve Adolescent Wellbeing?, Kristen H. Peterson Jan 2024

The Shifting Landscape Of Adolescent Wellness In Boarding Schools: Can Time Spent Off Screens And Outdoors Improve Adolescent Wellbeing?, Kristen H. Peterson

Dartmouth College Master’s Theses

For nearly twenty years I have worked directly with adolescents as an independent school educator. Whether in the classroom, on the field, or in the dorm, I have observed and supported students through their middle and high school experiences. During this time, I have witnessed an alarming shift in adolescent physical, emotional, and social wellbeing. Concurrently, I have observed a dramatic increase in the amount of time students spend using screen-based devices, and a decrease in their time spent outdoors.

Using research to ground my anecdotal accounts in empirical understanding, my thesis examines whether or not screen use might help …


(Meta-)Physical Artworks: Digital Augmentation In Art Observation, Macy A. Toppan Jan 2024

(Meta-)Physical Artworks: Digital Augmentation In Art Observation, Macy A. Toppan

Dartmouth College Master’s Theses

Augmented art— the subgenre of art that incorporates physical and digital artwork— is a rapidly growing field driven by advancing technology and a new generation for whom that tech is a given. Yet the presence of media like augmented and virtual reality in exhibition remains a controversial subject. Rather than focusing on the many theoretical debates about whether digital pieces can qualify as "good" art, we study it in practice through the eyes of the casual art observer. This paper highlights the audience in a within-participant study that asked viewers to take in a physical sculpture intentionally built with virtual …


Random Walk Methods For Geometry Representation Agnostic Transport, Dario R. Seyb Jan 2024

Random Walk Methods For Geometry Representation Agnostic Transport, Dario R. Seyb

Dartmouth College Ph.D Dissertations

In computer graphics, we use geometry representations to model a wide range of virtual scenes—from the fantastical worlds shown in animated movies to intricate mechanical parts.
These representations provide the context for transport problems—light transport is used to produce images of virtual scenes and diffusive transport to simulate distributions of quantities like heat.

There are many types of representations each with their own advantages.
For example, explicit ones make it easy to directly manipulate surfaces, while implicit representations allow for intuitive modeling by non-technical users and straightforward integration into machine learning systems.
Unfortunately, many algorithms that work on these digital …