Physical Sciences and Mathematics Commons^™

A Hyperbolic Relaxation Solver For Numerical Relativity, Thiago Assumpcao

Graduate Theses, Dissertations, and Problem Reports (ETD)

Numerical relativity (NR) simulations are essential for self-consistently modeling compact binary mergers, whose observations form the heart of gravitational-wave science. Stable NR simulations are the result of mathematical and computational breakthroughs spanning several decades: early attempts to numerically solve the two-body problem in General Relativity (GR) date back to the 1960s, while the first successful black-hole binary merger simulations were performed in 2005 with the generalized harmonic coordinates, and in 2006 using the moving-puncture gauge.

Today, NR continues to drive progress in gravity research, with ongoing efforts focused on increasing physical realism in simulations containing matter, exploring alternative theories of …

X-Ray Absorption And Related Studies In Superconducting Devices And Magnetic Thin Films, Ghadendra Bahadur Bhandari

Graduate Theses, Dissertations, and Problem Reports (ETD)

Superconducting and magnetic thin films are commonly used in sensors for analytical detectors, especially those that operate at very low temperatures, often below 1 Kelvin. These highly sensitive detectors, capable of functioning across a broad range of wavelengths, have garnered significant interest in scientific research. The focus of this thesis is to address a material challenge associated with an emerging technology known as microwave kinetic inductance detectors (MKIDs). The research involves the study of Al/Si and Al-Mn/Si-based thin films, as well as an investigation into the magnetic properties of LaMnO₃ thin films. LaMnO₃, a perovskite thin film that plays a …

A Floquet Solver For Time Periodic Open Quantum Systems, Fenton Ross Clawson

Graduate Theses, Dissertations, and Problem Reports (ETD)

Computational physics has been a backbone of experimental and theoretical physics since the 1940’s, when the first nuclear bomb and ballistic simulations were per- formed at Los Alamos Laboratory. Nowadays, however, simulation of open quan- tum systems has been formalized into coding packages and user-friendly functions, such as QuTiP or Qiskit, which allow users to simulate these systems without hav- ing the in-depth knowledge required to build the computational backbone from the ground-up. With the shift in modern quantum physics towards the realization of quantum computation, a strong computational background is still necessary to lend validity to theoretical results and …

Characterizing Prescribed Fire With Terrestrial Lidar In The New Jersey Pine Barrens, Samuel Rhule Stockton

Graduate Theses, Dissertations, and Problem Reports (ETD)

Prescribed burning has become a commonly used tool in the mitigation of wildfire, though monitoring the way it changes ecosystems has historically been a time-intensive process. Rapid change across ecosystems has necessitated advancements in remote sensing technologies to quantify the changes taking place. Single-scan terrestrial LiDAR scanning is one such method of monitoring these changes through the quantification of ecosystem structural characteristics. Acute disturbance events such as fire can transform the structure of an ecosystem, and by extension, change the way that ecosystem functions. The purpose of this study is to analyze the changes in vegetation density and distribution following …

Influence Of Attack Performance On The Ovc Volleyball Regular Seasons 2022 & 2023, Ignacio Valdemoros

Masters Theses

Understanding the outcome of volleyball games is necessary for coaches before, after, and during a season. There are several ways to gain this understanding, but statistical analysis is fundamental to see the minimum patterns of behavior that influence wins and losses in Volleyball. Furthermore, this analysis helps identify the optimal approach to achieving a goal and determining the most effective alternative to success. Scoring points in Volleyball involves three key skills: serving, blocking, and attacking. Among these skills, attacking plays the most relevant role in determining the outcome of a match. The position on the court (e.g. Outside Hitter, Middle …

The Relationship Between Metacognition, Study Strategies, And Students’ Performances In General Chemistry And Organic Chemistry Courses, Nghiem Uy Tieu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Many students find General Chemistry challenging, and studies have shown a link between students’ grades in chemistry and a decrease in interest in STEM fields. Similarly, Organic Chemistry has also been typically identified as a difficult course for many undergraduate students and has a notoriously high failure rate. Numerous studies have explored various methods to enhance students’ performance and experience in both General Chemistry and Organic Chemistry, but there hasn’t been much focus on students’ study strategies. In addition, metacognition, the skill of thinking about one’s thinking, had been proven in studies as a vital role in enhancing students’ achievements. …

Experimental Verification And Time-Resolved Bispectral Analysis Of Nonlinear Coupling In The Toroidicity-Induced Alfv´En Eigenmode Spectrum, Gregory Allen Riggs

Graduate Theses, Dissertations, and Problem Reports (ETD)

In magnetically-confined fusion devices, the toroidicity-induced Alfv´en eigenmode (TAE) is a well-studied, weakly stable solution of the linearized ideal magnetohydrodynamic (MHD) equations. Due to intrinsic coupling of poloidal harmonics of the shear Alfv´en wave (SAW) in toroidal geometry, the rotational transform of magnetic field lines modulates the effective index of refraction, ensuring gaps in the so-called “Alfv´en continuum.” Experimental verification of theoretical predictions for various parameters of interest (i.e., frequency, mode structure, instability threshold, etc.) is established in the literature.

We present the first systematic study of TAE-TAE phase coherence in an experimental device, using the DIII-D tokamak. Crucially, nonlinear …

Synthesis Of A Basket-Shaped Host Molecule Based On P-Tert-Butylcalix[4]Arene Featuring Pyridinyl Groups For Volatile Guest Molecule, Boluwatife S. Ajewole

Masters Theses

Supramolecular and Molecular chemistry offer an expanding array of applications for the development of smart devices, with calixarene-based molecular baskets playing a pivotal role in host-guest chemistry. A key concept in this field is the design of "smart" molecules with gate-like features, which can selectively transport chemical or biochemical species that are volatile, reactive, or sensitive to typical solution environments. These molecular hosts are engineered with predefined groups that respond to external stimuli, such as changes in concentration, temperature, or pH.

Molecular baskets are synthetic host molecules designed to capture guest molecules selectively through adjustable gates. In our study, we …

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 …

Hack24f: Ai Attacking Ai, Emry Hankins, Sofia Escobar, Yinxin Wan

Paul English Applied Artificial Intelligence (AI) Institute Publications

As MLaaS gains popularity, it also attracts new threats, in particular, model extraction attacks. These attacks involve unauthorized attempts to access and replicate AI models by querying and analyzing the response. Not only do these attacks pose a threat to security and safety but also compromises valuable intellectual property. Because businesses are increasing accessibility to their models that contain sensitive data, it is crucial that they are able to keep them safe and secure.

Hack24f: Careplus: Ai Chatbot, Arianna Fernandez, Sophia Cherkaoui

Paul English Applied Artificial Intelligence (AI) Institute Publications

90% of patients Google symptoms before they talk to their doctor. What are we developing? An app that asks for user symptoms and personal information, users AI to determine medical conditions and provides a plan of action, including recommended medications and suggested doctors to visit.

Hack24f: Llms And World Knowledge Problems, Chengtaon Lin, Joseph Lobo, Huuthanhvy Nguyen, Brian Santos, Ting Xu

Paul English Applied Artificial Intelligence (AI) Institute Publications

While AI “hallucinations” have been widely publicized by the media as shortcomings of Large Language Models (LLMs), there is much less awareness about shortcomings that derive from the potential lack of understanding of the world, from a potential lack of commonsense knowledge. We want to raise awareness among our student body about the potential fallibility of LLMs when they the problems that they need to solve require a basic understanding of the world. We hope that this awareness will prompt everyone to question more carefully the outputs generated by LLMs.

Hack24f: The Empathy Architects, Michael Rejtig, Ajanee Igharo, Emma Kelminson, Jackson Comeau

Paul English Applied Artificial Intelligence (AI) Institute Publications

Problem Statement: We want to help patients from underserved communities feel more safe, respected and comfortable in interacting with healthcare providers during the initial in-person encounters while also helping providers build empathy and implement socio-emotionally competent communication behaviors. Solution: Empathy Evolution is an AI-powered role-playing game that helps patients simulate their ideal communication with healthcare providers.

Hack24f: Using Ai To Support Teachers Working With Young Children With Challenging Behaviors, Muqing Zhang, Bennie Bendiksen, Songtian Zeng

Paul English Applied Artificial Intelligence (AI) Institute Publications

While coaching or mental health consultation can be a promising approach to support educators (Kang-Yi et al., 2018), the cost can be substantial and many school districts find it difficult to hire qualified personnel to coach the educators in need. Previous research has attempted to utilize mobile technology to support parents in addressing children with challenging behaviors (Meadan et al., 2016). There are few tools available to support teachers and that attempt to integrate AI technology in the program design and implementation. Our objective is to develop a prototype AI-based tool called Trick-or-Treat to support teachers in identifying and developing …

Hack24f: Beacon Pathway, Michael Agbesi, Ciara Santiago, David Martinez, Olivia Moos, Mohammed Mustafa

Paul English Applied Artificial Intelligence (AI) Institute Publications

The problem: There are a multitude of students from different backgrounds who are feeling lost in their academic journey at UMass Boston & need help with finding opportunities that fit their needs.

The solution: Developing Beacon Pathway, a user-centered platform designed to empower UMass Boston students from diverse backgrounds by streamlining their academic journey. This solution focuses on providing personalized resources, tailored opportunities, and community engagement, ensuring every student feels supported and connected as they navigate their unique paths to success

Hack24f: Tori Project: An Llm Powered Personal Assistant That Speaks, Inal Mashukov, Avi Felzenstein

Paul English Applied Artificial Intelligence (AI) Institute Publications

The problem: remember Jarvis from Iron Man? If not, Jarvis is an AI personal assistant to Tony Stark, aka Iron Man, which can speak in a human-like manner, and is in charge of the systems of the Iron Man suit. Tony Stark also relies on Jarvis for direct access to information, automation of his projects, and helping with work in general. Currently, the “best” real-world alternatives to Jarvis are Siri and Alexa. These are NOT particularly intelligent. Wouldn't it be nice to have a Jarvis-like assistant that is: actually intelligent and resourceful, sounds human, runs locally/offline on your phone or …

Hack24f: Ai And Mental Health: Addressing The Therapy Gap, Samatrai Piam, Digvijay Mahawar, Meric Kinali, Luxman Surentha, Jackson Comeau, Gail Rauch, Cody Turner

Paul English Applied Artificial Intelligence (AI) Institute Publications

Real-World Problem: There is a global shortage of mental health professionals, especially in underserved areas. AI-based chatbots could help fill this gap, but there are serious ethical concerns about the quality of care and efficacy of such chatbots.

Solution: This is a non-technical project that involved conversing with existing chatbots in an effort to develop a normative framework that could be used by future AI therapy bot developers. This framework seeks to build on, and operationalize, some of the insights from the recently published whitepaper on the ethics of chatbot therapy by the UMass Boston Applied Ethics Center. This presentation …

Hack24f: Examine The Human Creativity And Productivity In Ai Generated Content, Jongsoo Ha, Dante Barton, Onkar Khedkar, Neeti Shah, Yash Gondkar, Youxiang Zhu, Xiaohui Liang

Paul English Applied Artificial Intelligence (AI) Institute Publications

This project, presented at the Fall 2024 Hackathon, explores the balance between human creativity and productivity in the age of AI-generated content. With tools such as ChatGPT and Grammarly becoming integral to students’ academic workflows, questions surrounding originality, intellectual property, and academic integrity have grown increasingly urgent. The team addresses the challenge of distinguishing between human and AI contributions in content creation, particularly as current AI detection tools prove unreliable. Their proposed solution involves a system that not only detects AI-generated text using watermarking techniques but also quantifies contributions from humans and AI throughout the writing process.

Stability Of Organic Metal Halide Perovskites, S S M Tareq Hossain

Theses and Dissertations--Chemistry

Perovskites have emerged as a promising candidate for low-cost production of solar cells. However, the most critical barrier for commercialization of perovskite solar cells (PSCs) is the inadequate stability of the organic metal halide perovskites (OMHPs). The degradation of OMHPs is induced by light, heat, air, and electrical bias. The known degradation pathways involve the oxidation of I- and Sn2+, dissolution of perovskites by moisture, irreversible reactions with water, ion migration, and ion segregation. To improve the stability of OMHPs various methods are adopted, such as additive engineering, perovskite surface treatment, and composition engineering. Surface ligands are used on top …

Fundamental Studies Of Optical Properties And Electrocatalytic Properties Of Low Dimensional Nanomaterials Carbon Nano Dots And 2d Transition Metal Dichalcogenides, Nadeesha Kothalawala

Theses and Dissertations--Chemistry

Low dimensional nanomaterials are widely used in a variety of applications such as opto-electronics, energy production and storage, and bio-medical applications due to their unique optical, catalytic, electronic, and mechanical properties. Most of the nanomaterials offer a plethora of modifications in their structure, composition, morphology, and dimensionality that can lead to the manipulation of their physiochemical properties. This dissertation presents insight into two types of compelling nanomaterials: carbon nanodots (CND) and transition metal dichalcogenides (TMD), investigating their optical and electrocatalytic properties respectively.

Carbon nanodots (CND) are a promising class of photoluminescent nanomaterials that hold a significant potential in many optoelectronic …

Investigating The Behavior Of Redox–Active Organic Molecules In Electrochemical Energy Storage Through Experiment–Guided Computational Simulations, Anton Perera

Theses and Dissertations--Chemistry

The long–anticipated implementation of using renewable sources such as solar and wind to meet the world’s energy demand is still limited by not having appropriate grid–level energy storage systems on a global scale. When considering grid–scale energy storage solutions, environmental concerns, and techno–economic viability play a crucial role in the practical implementation of such technology. To address this, redox–active organic molecules (ROMs) have been explored for many uses including serving as redox–active molecules in redox flow batteries (RFBs) and providing overcharge protection in lithium–ion batteries (LIBs).

Nevertheless, in order to be a major player in electrochemical energy storage, further optimization …

Impacts Of Key Degradation Byproducts On Amine Scrubbing For Post-Combustion Carbon Capture, Thomas Jorgensen

Theses and Dissertations--Chemistry

The increasing atmospheric CO₂ concentration causes significant concern about global warming and its environmental impact. Industrial sectors, including power generation, transportation, and production factories, contribute most of the anthropogenic sources of CO₂ emissions. Researchers search for methods to mitigate these CO₂ emissions without compromising the benefits of industrial processes, including CO₂ capture, utilization, and sequestration (CCUS). Post-combustion carbon capture (PCCC) by amine scrubbing is the most technology ready CCUS, with various pilot-scale projects worldwide showing small-scale to fully operational plants. While researchers have made significant progress in amine scrubbing, they strive to improve the efficiency and …

Addition Reactions Of Olefinic Heterocycles And 4-Hydroxycoumarins, Benjamin Goka

Graduate Research Theses & Dissertations

The work outlined in this dissertation describes acid-base catalyzed projects facilitating the construction of key synthetic analogs with vast therapeutic applications. Three major projects have been covered demonstrating various synthetic routes developed by our research group to furnish key derivatives of heterocyclic compounds, including coumarins, carbohydrate moieties, and beta-lactams. By their catalytic nature, acids, and bases are known to enhance the reactivities of compounds. This allows synthetic chemists to design or chart new and better reaction pathways leading to the delivery of desired reaction products. The first chapter features a summary of the main concepts underpinning the projects.

Chapter 2 …

Superelectrophile Promoted Syntheses Of Aromatic Spirocycles, Jeffrey Caz Ferreira

Graduate Research Theses & Dissertations

Aromatic spirocycles are crucial organic scaffolds that are at the forefront of innovation in various fields of organic electronics, as well as in drug design. The synthesis of these compounds is challenging, especially on an industrial scale and often have suboptimal yields in many traditional syntheses. New synthetic methodologies are being continually explored for the installation of sp3 hydridized spiro junctions. Our research group, as well as other groups, have done exploration of using superelectrophilic synthetic routes that are nicely applied to the formation of aromatic spirocycles. Most relevant to the results discussed in this dissertation are condensation chemistry using …

Magnetotransport Properties Of Dirac Semimetal Taco2te2 And Ferromagnetic Weyl Semimetal Co3sn2s2, Samuel Pate

Graduate Research Theses & Dissertations

This dissertation investigates the magnetotransport properties of topological semimetals, specifically focusing on the Dirac semimetal TaCo2Te2 and the Weyl semimetal Co3Sn2S2. In TaCo2Te2, I observed extremely large magnetoresistance that violates Kohler’s rule. Extended Kohler’s rule can be applied with a calculation of Hall factor at low temperatures. I also explored the applicability of the two-band and four-band models of carrier analysis and correlate the region where Kohler’s rule is obeyed to the four-band model. In Co3Sn2S2, I explored the angle-dependent anomalous Hall effect (AHE) near the Kagome plane, revealing a tunable AHE under applied fields and an abrupt disappearance of …

Exploring The Connection: Field Ecology Research And Student Wellbeing, Elizabeth Small

Graduate Research Theses & Dissertations

Field work is essential in ecological research, offering the opportunity to gather firsthand data, observe natural processes, and deepen our understanding of ecosystems. In my study on small mammal trophic niche dynamics, I investigate how small mammals—critical players in grassland food webs—adapt their diets in response to environmental disturbances. By examining the drivers of variation in trophic niche among three common small mammal species, I aim to uncover how these animals coexist despite similar dietary requirements. Understanding these dynamics is critical for informing global conservation efforts, especially as we work to reverse the biodiversity crisis and restore damaged ecosystems.However, the …

Explicitly Counting Subspaces Of Given Height Defined Over A Field Of Rational Functions, Kakoli Bhuyan

Graduate Research Theses & Dissertations

A height function measures the complexity of mathematical objects, usually points on some projective variety. There are previous results that estimate the number of subspaces of bounded height defined over number fields and function fields over a finite field. These results are asymptotic estimates as the height bound tends to infinity. In this dissertation we derive an explicit counting of the number of subspaces of given height defined over a field of rational functions.

Increasing Retention Of Women In Hunting And Fishing, Shelby Isensee

Electronic Theses and Dissertations

Despite national declines in hunting and fishing, women are making inroads in historically male-dominated sports. To further encourage women’s participation, states established programs to recruit, retain, and reactivate [R3] hunters and anglers. Women are participating in these programs and other recreational groups to access opportunities to learn skills and grow their networks. Yet, very little is known about what programs are offered for women, what aspects of programs are most effective to support women’s retention in these activities, and what women’s hunting and fishing groups are available across the landscape. To address these questions, I collected qualitative data from participant …

A Little More On Ideals Associated With Sublocales, Oghenetega Ighedo, Grace Wakesho Kivunga, Dorca Nyamusi Stephen

Mathematics, Physics, and Computer Science Faculty Articles and Research

As usual, let RL denote the ring of real-valued continuous functions on a completely regular frame L. Let βL and λL denote the Stone- Čech compactification of L and the Lindelöf coreflection of L, respectively. There is a natural way of associating with each sublocale of βL two ideals of RL, motivated by a similar situation in C(X). In [12], the authors go one step further and associate with each sublocale of λL an ideal of RL in a manner similar to one of the ways one does it for sublocales of βL. The intent in this paper …

Estimation Of Methyl Orange Dye's Molar Absorptivity Using A Photoresistor-Based Photometer, Patricia M. Ludovice, Ramon M. Delos Santos

Physics Faculty Publications

The need to further develop solar cell technology, particularly on dye-sensitized solar cells (DSSCs), drives absorption studies of various chemical species. In this study, absorbance analysis of methyl orange (MO) dye was performed using the adapted and modified photoresistor-based photometer of Adams-McNichol et al. [1]. The research aims to improve the stability of the reference setup, while maintaining the accuracy of absorbance results it yields. The methodology includes photometer fabrication, MO dye sample preparation, and the evaluation of MO dye's molar absorptivity in an aqueous solution. Results show that the estimated molar absorptivity of MO using the voltage readings from …