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Full-Text Articles in Physical Sciences and Mathematics

Gamelan Gong Directivity Dataset, Samuel D. Bellows, Dallin T. Harwood, Kent L. Gee, Micah R. Shepherd Jan 2023

Gamelan Gong Directivity Dataset, Samuel D. Bellows, Dallin T. Harwood, Kent L. Gee, Micah R. Shepherd

Directivity

No abstract provided.


Molecular Organic Photovoltaic Cells And Applications, Julie Liu Jan 2023

Molecular Organic Photovoltaic Cells And Applications, Julie Liu

Theses and Dissertations

The absorption, light scattering, and anti-Stoke’s fluorescence of chlorophyll and closely related sodium copper chlorophyllin were examined in various solutions with a wide range of refractive index and permittivity. It was evident that radiative photo electron decay corresponded to low permittivity solvents, but not to solvent refractive index. Additionally, non-radiative decay was dominant in high permittivity solvents. The properties suggest evolution has provided plants with an ability to redirect light to the chlorophyll in the high permittivity (water) photosynthesis center. Exploratory solar cells exploiting lifetime switching were developed and tested, wherein strong photovoltaic response was exhibited, along with the unique …


Wicked Problems And The Invention Of Calculus, Ernesto Diaz Jan 2023

Wicked Problems And The Invention Of Calculus, Ernesto Diaz

Natural Sciences and Mathematics | Faculty Scholarship

Since the 1980s, wicked problems have represented a category of challenges that defy clear description, cannot be addressed with existing models or theories, and resist experimentation in trying to solve them. This class of problems existed before they were identified and have been unsuccessfully addressed with Thomas Kuhn’s model of scientific discovery, an expectation that requires the identification of a new object and the development of its correct interpretation. This paper proposes an alternative view of scientific discovery using the invention of Calculus as a case study that describes a successful process addressing wicked-like problems from a philosophical perspective, develops …


Attending To The Cultures Of Data Science Work, Lindsay Poirier Jan 2023

Attending To The Cultures Of Data Science Work, Lindsay Poirier

Statistical and Data Sciences: Faculty Publications

This essay reflects on the shifting attention to the “social” and the “cultural” in data science communities. While recently the “social” and the “cultural” have been prioritized in data science discourse, social and cultural concerns that get raised in data science are almost always outwardly focused – applying to the communities that data scientists seek to support more so than more computationally-focused data science communities. I argue that data science communities have a responsibility to attend not only to the cultures that orient the work of domain communities, but also to the cultures that orient their own work. I describe …


Editor’S Note, Deepak Shimkhada Jan 2023

Editor’S Note, Deepak Shimkhada

Monsoon: South Asian Studies Association Journal

This special issue of Monsoon is dedicated to the studies honoring the goddess traditions in South Asia. The onset of the Monsoon Season in South Asia typically commences in June and continues until late August and early September. The publication of this issue, therefore, has been strategically timed to coincide with that season, which is a vital source of sustenance for millions of individuals in this part of the world. This anthology consisting of five papers—written by scholars with expertise in the field of goddess and women studies—speak unequivocally about the goddesses or women for their strength, beauty, wisdom, and …


Mai Bhago And Amrita Devi Bishnoi: Women Of Strength, Sowmya Ayyar Jan 2023

Mai Bhago And Amrita Devi Bishnoi: Women Of Strength, Sowmya Ayyar

Monsoon: South Asian Studies Association Journal

Mai Bhago (1670-1720), also known as Bhag Kaur, distinguished herself on the battlefield to defend the Sikh faith. Amrita Devi Bishnoi (d. 1730) is said to have sacrificed her life with 362 others to protect the Khejari trees in the Rajasthan desert. Both women continue to inspire social justice and ecological activism.


Development Of A Framework To Support Community-Scale Nutrient Recovery For Local Crop Fertilization And Production, Scott A. Lopez Jan 2023

Development Of A Framework To Support Community-Scale Nutrient Recovery For Local Crop Fertilization And Production, Scott A. Lopez

Graduate Theses, Dissertations, and Problem Reports

Nutrient and resource recovery (NRR) has become increasingly crucial as regions face deteriorating sanitation infrastructures, limited support, and growing environmental challenges. Implementing region-specific NRR technologies and systems could provide effective circular economy insights into addressing these challenges. Because of the multidisciplinary challenges associated with the design and implementation of NRR strategies, various government and local decision-makers need to collaborate effectively in the decision-making process. Structured decision-making (SDM) methodologies are practical when determining the most appropriate NRR strategy for nutrient-rich waste streams. However, applications of computational SDM limited because of the vast amounts of data that are needed to analyze the …


Machine Learning Prediction Of Dod Personal Property Shipment Costs, Tiffany Tucker [*], Torrey J. Wagner, Paul Auclair, Brent T. Langhals Jan 2023

Machine Learning Prediction Of Dod Personal Property Shipment Costs, Tiffany Tucker [*], Torrey J. Wagner, Paul Auclair, Brent T. Langhals

Faculty Publications

U.S. Department of Defense (DoD) personal property moves account for 15% of all domestic and international moves - accurate prediction of their cost could draw attention to outlier shipments and improve budget planning. In this work 136,140 shipments between 13 personal property shipment hubs from April 2022 through March 2023 with a total cost of $1.6B were analyzed. Shipment cost was predicted using recursive feature elimination on linear regression and XGBoost algorithms, as well as through neural network hyperparameter sweeps. Modeling was repeated after removing 28 features related to shipment hub location and branch of service to examine their influence …


Aircraft Damage Classification By Using Machine Learning Methods, Tüzün Tolga İnan Jan 2023

Aircraft Damage Classification By Using Machine Learning Methods, Tüzün Tolga İnan

International Journal of Aviation, Aeronautics, and Aerospace

Safety is the most significant factor that affected incidents (non-fatal) and accidents (fatal) in civil aviation history related to scheduled flights. In the history of scheduled flights, the total incident and accident number until 2022 is 1988. In this study, 677 of them are taken into consideration since 11 September 2001. The purpose of this study is to reveal the factors that can classify type of aircraft damages such as none, minor and substantial in all-time incidents and accidents. ML algorithms with different configurations are applied for the classification process. The RFE and PCA are used to find the most …


Rage Against The Machine: Who Is Responsible For Regulating Generative Artificial Intelligence In Domestic And Cross-Border Litigation?, S. I. Strong Jan 2023

Rage Against The Machine: Who Is Responsible For Regulating Generative Artificial Intelligence In Domestic And Cross-Border Litigation?, S. I. Strong

Faculty Articles

In 2023, ChatGPT—an early form of generative artificial intelligence (AI) capable of creating entirely new content—took the world by storm. The first shock came when ChatGPT demonstrated its ability to pass the U.S. bar exam. Soon thereafter, the world learned that ChatGPT was being used by both lawyers and judges in actual litigation.

Some within the legal community find the use of generative AI in civil and criminal litigation entirely unproblematic. Others find generative AI troubling as a matter of due process and procedural fairness due to its propensity not only to misinterpret legitimate legal authorities but to create fictitious …


Examining The Feasibility Of Identifying Tau Neutrino Charged Current Events In The Dune Far Detector, Sarah Choate Jan 2023

Examining The Feasibility Of Identifying Tau Neutrino Charged Current Events In The Dune Far Detector, Sarah Choate

Graduate Research Theses & Dissertations

Neutrinos began as theoretical, massless particles, and since their first detection they have continued to be the subject of various experiments. One such experiment is DUNE, which is a long baseline neutrino experiment with the goal of studying neutrino properties, such as neutrino oscillation parameters. In this work, two projects were completed, one dealing with the hardware of DUNE and the other dealing with neutrino simulations. For the hardware project, we designed a quality control method for testing adaptor boards which make up part of the Far Detector circuit boards. This method was completed and prototyped, however was not implemented …


Synthetic Methodologies Using Nucleophile-Electrophile Chemistry, Jacob C. Hood Jan 2023

Synthetic Methodologies Using Nucleophile-Electrophile Chemistry, Jacob C. Hood

Graduate Research Theses & Dissertations

Synthetic organic chemistry is a vital part of the modern world – making up 15-20% of the U.S. economy. New synthetic reactions can lower manufacturing costs and create more environmentally friendly processes. Substitution, addition, and superelectrophilic chemistry are potent tools to afford potentially essential compounds. The work outlined in this dissertation recounts the expansion of synthetic methodologies employing substrates with a wide range of electrophilicities toward synthesizing heterocyclic molecules. These concepts are summarized in chapter 1. Chapter 2: N-Heterocyclic alcohols are excellent substrates for superacid-promoted Friedel-Crafts reactions. The N-heterocyclic alcohol ionizes to produce reactive, dicationic intermediates, providing good to excellent …


Study Of The Dynamics Of Glasses Using Nuclear Resonance Time Domain Interferometry, Marc Pavlik Jan 2023

Study Of The Dynamics Of Glasses Using Nuclear Resonance Time Domain Interferometry, Marc Pavlik

Graduate Research Theses & Dissertations

Nuclear resonance time domain interferometry (NR-TDI) is used to study the slow dy- namics of liquids (that do not require M ̈ossbauer isotopes) at atomic and molecular length scales between 1 A to 10 nm and at time scales between 1 ns to 10 μs. This new spectroscopy technique covers a new range of previously unexplored momentum transfers between 1 to 100 nm−1 and energies between 10 peV to 100 neV allowing an investigation into the dynami- cal motion of molecules, liquids, and glasses. The notoriously low count rate from quasielastic scattering experiments makes measurements difficult when using synchrotron x-rays …


Contractions Of Simple Continued Fractions, Nicholas J. Davis Jan 2023

Contractions Of Simple Continued Fractions, Nicholas J. Davis

Graduate Research Theses & Dissertations

In this thesis, we will explore contractions of simple continued fractions and prove the General Contraction Theorem from scratch. We introduce sequences of matrices that will prove useful.


Switchable Anomalous Hall Effects In Polar-Stacked 2d Antiferromagnet Mnbi2Te4, Tengfei Cao, Ding-Fu Shao, Kai Huang, Gautam Gurung, Evgeny Y. Tsymbal Jan 2023

Switchable Anomalous Hall Effects In Polar-Stacked 2d Antiferromagnet Mnbi2Te4, Tengfei Cao, Ding-Fu Shao, Kai Huang, Gautam Gurung, Evgeny Y. Tsymbal

Department of Physics and Astronomy: Faculty Publications

Van der Waals (vdW) assembly allows controlling symmetry of two-dimensional (2D) materials that determines their physical properties. Especially interesting is the recently demonstrated breaking inversion symmetry by polar layer stacking to realize novel electronic, magnetic, and transport properties of 2D vdW materials switchable by induced electric polarization. Here, based on symmetry analyses and density-functional calculations, we explore the emergence of the anomalous Hall effect (AHE) in antiferromagnetic MnBi2Te4 films assembled by polar layer stacking. We demonstrate that breaking 𝑃̂ 𝑇̂ symmetry in an MnBi2Te4 bilayer makes this 2D material magnetoelectric and produces a spontaneous AHE switchable by …


Anisotropic Optical And Magnetic Response In Self-Assembled Tin-Cofe2 Nanocomposites, Jiawei Song, Di Zhang, Ping Lu, Haohan Wang, X. S. Xu, Melissa L. Meyerson, Samantha G. Rosenberg, Julia Deitz, Juncheng Liu, Xuejing Wang, Xinghang Zhang Jan 2023

Anisotropic Optical And Magnetic Response In Self-Assembled Tin-Cofe2 Nanocomposites, Jiawei Song, Di Zhang, Ping Lu, Haohan Wang, X. S. Xu, Melissa L. Meyerson, Samantha G. Rosenberg, Julia Deitz, Juncheng Liu, Xuejing Wang, Xinghang Zhang

Department of Physics and Astronomy: Faculty Publications

Transition metal nitrides (e.g., TiN) have shown tremendous promise in optical metamaterials for nanophotonic devices due to their plasmonic properties comparable to noble metals and superior high temperature stability. Vertically aligned nanocomposites (VANs) offer a great platform for combining two dissimilar functional materials with a one-step deposition technique toward multifunctionality integration and strong structural/property anisotropy. Here we report a two-phase nanocomposite design combining ferromagnetic CoFe2 nanosheets in the plasmonic TiN matrix as a new hybrid plasmonic metamaterial. The hybrid metamaterials exhibit obvious anisotropic optical and magnetic responses, as well as a pronounced magneto-optical coupling response evidenced by MOKE measurement, …


Interface-Tuning Of Ferroelectricity And Quadruple-Well State In Cuinp2S6 Via Ferroelectric Oxide, Kun Wang, Du Li, Jia Wang, Yifei Hao, Hailey Anderson, Li Yang, Xia Hong Jan 2023

Interface-Tuning Of Ferroelectricity And Quadruple-Well State In Cuinp2S6 Via Ferroelectric Oxide, Kun Wang, Du Li, Jia Wang, Yifei Hao, Hailey Anderson, Li Yang, Xia Hong

Department of Physics and Astronomy: Faculty Publications

Ferroelectric van der Waals CuInP2S6 possesses intriguing quadruple-well states and negative piezoelectricity. Its technological implementation has been impeded by the relatively low Curie temperature (bulk TC ~42 °C) and the lack of precise domain control. Here we show that CuInP2S6 can be immune to the finite size effect and exhibits enhanced ferroelectricity, piezoelectricity, and polar alignment in the ultrathin limit when interfaced with ferroelectric oxide PbZr0.2Ti0.8O3 films. Piezoresponse force microscopy studies reveal that the polar domains in thin CuInP2S6 fully conform to those of underlying …


Mapping Maple Memory, Grace Derksen Jan 2023

Mapping Maple Memory, Grace Derksen

Senior Projects Spring 2023

Senior Project submitted to The Division of Multidisciplinary Studies of Bard College.


From Sine Waves To Soundscapes: Exploring The Art And Science Of Analog Synthesizer Design, Saiqi Zhang Jan 2023

From Sine Waves To Soundscapes: Exploring The Art And Science Of Analog Synthesizer Design, Saiqi Zhang

Senior Projects Spring 2023

Senior Project submitted to The Division of Science, Mathematics and Computing of Bard College.


Using Berries To Turn Sunlight Into Electricity: Taking Advice From Mother Nature Because She Has Already Mastered The Art Of Using Solar Energy, Quincy Ross Jan 2023

Using Berries To Turn Sunlight Into Electricity: Taking Advice From Mother Nature Because She Has Already Mastered The Art Of Using Solar Energy, Quincy Ross

Senior Projects Spring 2023

As we try to stop anthropogenic climate change, we need to find energy sources that don’t involve burning fossil fuels. The Earth is constantly being hit with energy in the form of sunlight, we just need to figure out how to use it, thankfully plants have already gotten very good at photosynthesis. Solar energy is being improved at an exciting rate but has some material downsides when it comes to raw material mining. Dye sensitized solar cells, though having a lower efficiency than traditional photovoltaics open up opportunities for improving solar energy in many other aspects, such as reducing material …


Theoretical Foundations Of Quantum Computing And The Implementation Of The Quantum Fourier Transform, Natalia Dziubelski Jan 2023

Theoretical Foundations Of Quantum Computing And The Implementation Of The Quantum Fourier Transform, Natalia Dziubelski

Senior Projects Spring 2023

Quantum computing is a growing field with the potential to revolutionize computation. This thesis explores the foundations of quantum computing with specific focus on the efficacy of the Quantum Fourier Transform (QFT). The fundamentals of quantum computing were described through an explanation of quantum mechanics and the mathematics needed to understand the quantum computing model and its operations. Using IBM’s simulators and quantum processors, the QFT was implemented on a classical data set, and the results were compared to the predicted output values. It was found that the QFT simulator was able to produce results consistent with Discrete Fourier Transform, …


Logistics Planning: Putting Math To Work In A Business Setting, Michael C. Hannan Jan 2023

Logistics Planning: Putting Math To Work In A Business Setting, Michael C. Hannan

Senior Projects Spring 2023

The optimization of business procedures benefits all aspects of the product. Maximizing efficiency can lead to more profits for the business, cheaper products for the consumer, and less fuel consumption for the environment. Tracing the history of optimization, we can see that people have always strived for the most efficient way to allocate scarce resources. However, the field of optimization did not blossom until innovations in mathematics allowed us to solve a majority of real world problems. The discovery of linear and nonlinear programming in the 1940s allowed us to optimize problems that were unsolvable before. This paper introduces how …


Mathematical Structure Of Musical Tuning Systems, Shay Joel Francis Spitzer Jan 2023

Mathematical Structure Of Musical Tuning Systems, Shay Joel Francis Spitzer

Senior Projects Spring 2023

Over the course of history, western music has created a unique mathematical problem for itself. From acoustics, we know that two notes sound good together when they are related by simple ratios consisting of low primes. The problem arises when we try to build a finite set of pitches, like the 12 notes on a piano, that are all related by such ratios. We approach the problem by laying out definitions and axioms that seek to identify and generalize desirable properties. We can then apply these ideas to a broadened algebraic framework. Rings in which low prime integers can be …


Examining Stellate Unions, Julia Erin Crager Jan 2023

Examining Stellate Unions, Julia Erin Crager

Senior Projects Spring 2023

Stellate neighborhoods are created by gluing half disks together along their straight edges. A 1-stellate neighborhood is a half disk, a 2-stellate neighborhood is a disk, a 3-stellate neighborhood is 3 half disks glued together to make a star-like shape, and so on. For a topological space $X$, and for each $n \in \nn$, the $n$-stellate subspace of $X$ is the set of all points in $X$ that have a neighborhood homeomorphic to an $n$-stellate neighborhood. I will be examining topological spaces called stellate unions, where each point in the space is contained in an $n$-stellate subspace for some $n …


Quandle Unification Reduces To Quandle Matching, Maximus Redman Jan 2023

Quandle Unification Reduces To Quandle Matching, Maximus Redman

Senior Projects Spring 2023

The purpose of this project is to show that quandle unification reduces to quandle matching. We show that any unification problem $U$ can be embedded into a matching problem $M$. If a unifier exists for $M$, then the narrowing sequence $N$ of that unifier can be refactored to $N'$ such that all of its idempotence narrowing steps involving substitutions are done last. At the moment when the narrowing sequence $N'$ needs only to do idempotence steps to unify $M$, we show that this implies a form for the embedded matching problem $U$ such that $U$ is guaranteed to have a …


Parking Garage Functions, Felicia Elizabeth Flores Jan 2023

Parking Garage Functions, Felicia Elizabeth Flores

Senior Projects Spring 2023

Senior Project submitted to The Division of Science, Mathematics and Computing of Bard College.

This project is about a generalization of parking functions called parking garage functions. Parking functions have been well studied, but the concept of parking garage functions is new and introduced in the project. Parking garage functions are sequences that represent the parking garage level preferences of cars which lead to all cars parking on a level after a systematic placement. We found a recursive formula for the number of sequences that are a parking garage function. We also found a closed formula for a subset of …


Compiling Quantum Programs, Li-Heng Henry Chang Jan 2023

Compiling Quantum Programs, Li-Heng Henry Chang

Senior Projects Spring 2023

This thesis introduces the quantum compilation problem and develops a prototypical compiler. The problem of quantum compiling is, in essence, converting high-level human expressions of quantum programs into low-level hardware executable code. Compilers that target different hardware platforms enable portable code that can be used to benchmark hardware performance, reduce programming work and speed up development. Because quantum systems are subjected to phenomena such as noise, no-cloning and decoherence, the challenge of quantum compiling is tied to the optimization of program runtimes and the lengths of compiled sequences. For near-term intermediate scale quantum (NISQ) computers with limited hardware resources and …


Acceptable Title Pending: Probing The Limits Of Precision Measurement And Academic Assessment, Bobby King Jan 2023

Acceptable Title Pending: Probing The Limits Of Precision Measurement And Academic Assessment, Bobby King

Senior Projects Spring 2023

This is a project in two parts. The first is an attempt to impart onto the reader the necessary mental models required to understand a scientific experiment related to the improvement of gravitational wave detectors. Part one is illustrated in collaboration with Simone River Wilding, Sohpie Foley, Roma Taitwood, and Cam Goldberg.

Part two is a technical description of efforts made to reduce speckle in measurements of scattered light. Gravitational wave detection requires extremely high precision measurement, and one source of noise in the detectors is scattering off of defects and surface roughness in optical coatings. Research into the development …


Spotting K-Tricaps In Spot It!, Jenarah Skyara Lara Jan 2023

Spotting K-Tricaps In Spot It!, Jenarah Skyara Lara

Senior Projects Spring 2023

The card game “SPOT IT!” consists of 55 cards, with 8 symbols appearing on each card. Every pair of cards has exactly one symbol in common, and the goal of the game is to be the first person to find this symbol. An alternate way to play the game is to find sets of 3 cards that have the same symbol in common. We will use combinatorics, probability, and finite projective geometry to analyze the structure of the game. The game “SPOT IT!” can be viewed as the projective plane of order 7. However, we can construct a similar game …


Winona State University News Blog: 2015-February 2023, Winona State University Jan 2023

Winona State University News Blog: 2015-February 2023, Winona State University

Winona State University Blogs

This PDF document includes Winona State University (WSU) News Blog articles and entries for the university from 2015-May 2023.