Physical Sciences and Mathematics Commons^™

Spike Nozzle Design For Use In Nanosat Orbital Maneuvering, Drew Nemeth

Undergraduate Research Symposium Podium Presentations

Annular spike nozzle engines have long been the holy grail of rocket engine design, promising superior performance in a smaller footprint when compared to conventional bell nozzles. However, flaws inherent to the design of spike nozzles have prevented widespread adoption and testing. As a result, research on potential applications has been quite sparse. This project aims to further spike nozzle research by investigating rarely tested materials that literature suggests have potential for use in a spike nozzle design. The goal of the overall research project is to examine 3D printed polycarbonate component longevity under conditions representative of a small satellite …

Investigating The Varying Behaviors Of Magnesium, Tin, And Lead Oxalate Under High-Pressure, Kevin Ayala Pineda

Undergraduate Research Symposium Posters

Recent developments in the field of useful hard x-ray induced chemistry synthesized a novel strontium-based CO derived material under extreme conditions. In hopes of synthesizing this material in larger quantities and in less expensive costs, we report three high-pressure Diamond Anvil Cell investigations on Tin Oxalate (SnC2O4), Magnesium Oxalate (MgC2O4), and Lead Oxalate (PbC2O4) subjected to extreme conditions without the use of hard x-rays. MgC2O4 were acquired up to 25 GPa, with a possible phase transition at 2.4 Gpa. SnC2O4 was pressurized up to 31 GPa inducing irreversible changes in both the Raman spectra and its qualitative properties. Three phase …

Somewhere Over The Rainbow: Exploring The Sense For Relevance In Children, Monica Landoni, Theo Huibers, Emiliana Murgia, Mohammad Aliannejadi, Maria Soledad Pera

Computer Science Faculty Publications and Presentations

We explore the facets of relevance that guide children when assessing materials retrieved by search engines when looking for information in the classroom. We involved children in a collaborative exercise and asked them to design innovative icons to point their peers towards useful results. We also asked them to complete a survey meant to capture explicit motivators guiding their design. This resulted in a rich set of metaphors. Analysis of the emerging metaphors is what allowed us to identify and discuss the many interpretations of relevance children naturally assign to resources they find in response to school-related information discovery …

Radiofrequency Spectroscopy Of One-Dimensional Trapped Bose Polarons: Crossover From The Adiabatic To The Diabatic Regime, Simeon I. Mistakidis, G. M. Koutentakis, F. Grusdt, H. R. Sadeghpour, P. Schmelcher

Physics Faculty Research & Creative Works

We Investigate The Crossover Of The Impurity-Induced Dynamics, In Trapped One-Dimensional Bose Polarons Subject To Radio Frequency (RF) Pulses Of Varying Intensity, From An Adiabatic To A Diabatic Regime. Utilizing Adiabatic Pulses For Either Weak Repulsive Or Attractive Impurity-Medium Interactions, A Multitude Of Polaronic Excitations Or Mode-Couplings Of The Impurity-Bath Interaction With The Collective Breathing Motion Of The Bosonic Medium Are Spectrally Resolved. We Find That For Strongly Repulsive Impurity-Bath Interactions, A Temporal Orthogonality Catastrophe Manifests In Resonances In The Excitation Spectra Where Impurity Coherence Vanishes. When Two Impurities Are Introduced, Impurity-Impurity Correlations, For Either Attractive Or Strong Repulsive Couplings, …

Indium Oxide-Based Catalysts For Solar Fuel Generation, Ryan Hagmann

WWU Honors College Senior Projects

The need to pursue renewable, carbon neutral forms of energy has led to a far reaching-research effort to generate and store solar energy. It has been shown that indium oxide-based catalysts have the potential to reduce carbon dioxide to carbon monoxide or even continue reduction to methanol. Recent advances and current challenges in further developing indium oxide catalysis as a means of producing a sustainable liquid fuel supply will be addressed. This project will give an overview of the research in indium oxide catalysts for solar fuels generation and the immediate relevance of recent work within the Bussell Research Group …

Wandering Whatcom Falls, Hailey Schmidt

WWU Honors College Senior Projects

Wandering Whatcom Falls is an interactive walking loop focused on connection and ecosystems. It takes place at Whatcom Falls and runs as a scavenger hunt with 7 different activities throughout the loop.

On The Menger And Almost Menger Properties In Locales, Tilahun Bayih, Themba Dube, Oghenetega Ighedo

Mathematics, Physics, and Computer Science Faculty Articles and Research

The Menger and the almost Menger properties are extended to locales. Regarding the former, the extension is conservative (meaning that a space is Menger if and only if it is Menger as a locale), and the latter is conservative for sober T_D-spaces. Non-spatial Menger (and hence almost Menger) locales do exist, so that the extensions genuinely transcend the topological notions. We also consider projectively Menger locales, and show that, as in spaces, a locale is Menger precisely when it is Lindelöf and projectively Menger. Transference of these properties along localic maps (via direct image or pullback) is considered.

Zn Acceptors In Β-Ga2O3 Crystals, Timothy D. Gustafson, J. Jesenovec, Christopher A. Lenyk, Nancy C. Giles, J. S. Mccloy, M. Mccluskey, Larry E. Halliburton

Faculty Publications

Electron paramagnetic resonance (EPR) is used to identify and characterize neutral zinc acceptors in Zn-doped β-Ga₂O₃ crystals. Two EPR spectra are observed at low temperatures, one from Zn ions at tetrahedral Ga(1) sites (the Zn⁰_Ga1 acceptor) and one from Zn ions at octahedral Ga(2) sites (the Zn⁰_Ga2 acceptor). These Zn acceptors are small polarons, with the unpaired spin localized in each case on a threefold coordinated oxygen O(I) ion adjacent to the Zn ion. Resolved hyperfine interactions with neighboring ⁶⁹Ga and ⁷¹Ga nuclei allow the EPR spectra from the two acceptors …

Free Semigroupoid Algebras From Categories Of Paths, Juliana Bukoski

Department of Mathematics: Dissertations, Theses, and Student Research

Given a directed graph G, we can define a Hilbert space H_G with basis indexed by the path space of the graph, then represent the vertices of the graph as projections on H_G and the edges of the graph as partial isometries on H_G. The weak operator topology closed algebra generated by these projections and partial isometries is called the free semigroupoid algebra for G. Kribs and Power showed that these algebras are reflexive, and that they are semisimple if and only if each path in the graph lies on a cycle. We extend …

Gauge-Invariant Uniqueness And Reductions Of Ordered Groups, Robert Huben

Department of Mathematics: Dissertations, Theses, and Student Research

A reduction φ of an ordered group (G,P) to another ordered group is an order homomorphism which maps each interval [1, p] bijectively onto [1, φ(p)]. We show that if (G,P) is weakly quasi-lattice ordered and reduces to an amenable ordered group, then there is a gauge-invariant uniqueness theorem for P -graph algebras. We also consider the class of ordered groups which reduce to an amenable ordered group, and show this class contains all amenable ordered groups and is closed under direct products, free products, and hereditary subgroups.

Adviser: Mark Brittenham and David Pitts

The Q-Gauss Product, Q-Trigonometry Via Landen-Like Identities, And Positive Alternating Q-Series, Sarah Abo Touk

Theses

The object of this report is q-series and their relationship with certain special functions. Firstly, Jackson’s q-analogue of the Euler gamma function is introduced and a q-analogue for a famous formula of Gauss on products of the gamma function will be presented. Secondly, Jacobi’s theta functions will be discussed in details and new Landenlike half argument formulas will be established. As an application, q-trigonometric formulas shall be derived and a new proof for a well-known q-series relation of Jacobi will be given. Thirdly, an extended Bailey transform will be presented and a variety of new q-series will be deduced as …

Fabrication Of Chemically-Functionalized 3dprinted Porous Scaffolds For Biomedical Applications, Eiman Hamed Matar Atalla Alblooshi

Theses

Hard tissues, such as bone and teeth, are natural composites of collagen nanofibers that are reinforced by inorganic calcium phosphate Nano crystallites, in the form of nanocomposites. The interlocking between these components in hard tissues explains their unique characteristics. Bone is mainly classified into two major types; compact and cancellous depending on the extent of porosity. Fractures in the compact bone can be treated using bone fixation implants, such as rods, screws, and plates, or can be totally replaced by bone implants if complete substitution is required. Cancellous bone, on the other hand, is highly porous and its substitution with …

Controllability And Observability Of Blood Glucose Levels And The Impact Of Covid-19 On Diabetic Patients, Mahra Salem Nasser Abdulla Alblooshi

Theses

Diabetes is a metabolic disorder that is characterized by high blood glucose concentrations resulting from insulin deficiency in case of type 1 or insulin inefficiency in case of type 2. While no cure for diabetes exists, the artificial pancreas is a possible way to manage diabetes, especially for type 1 diabetics. Where an artificial pancreas is a closed-loop control system with an integrated mathematical model. This control system imitates the function of a healthy pancreas. The first part of this thesis is concerned with the control system of an artificial pancreas that is based on Bergman’s minimal model of glucose-insulin …

Partial Oxidation Of Methane To Synthesis Gas Over Ni/Γ-Al₂O₃ Catalysts: The Effect Of The Structure And The Pre-Treatment Of The Support On The Catalysts’ Performance, Sheikh Tijan Jobe

Theses

Abundant natural gas is a potential source of more cost-effective energy and its effective utilization can significantly reduce the dependence on petroleum oil. Disadvantages of natural gas as a direct fuel include its low energy density by volume, and high cost of transportation, which resulted in its underutilization as an alternative energy source. Therefore, the conversion of methane to more easily-handled and value-added products is becoming a promising route for natural gas utilization. Compared to steam reforming of methane to syngas, which is the most commercially applied conversion process, partial oxidation is a more cost-effective promising route. While noble metals …

Levels Of Testosterone Esters In Camel Hair, Aysha Khalidi Ali Alraeesi

Theses

Doping and steroid use represent a serious threat to animal health and can even lead to their untimely and painful death. However, doping is an acute problem in today's animal racing world, particularly in camel racing. Testosterone and its ten esters (benzoate, valerate, isocaproate, hexahydrobenzoate, decanoate, undecanoate, laurate, enanthate, cypionate, and caproate) are of utmost importance because when they are administered to animals it is difficult to measure them efficiently. The levels of testosterone and its esters in camels and other animals are typically determined using urine and blood tests. The aim of this study was to develop and validate …

Mechanisms Driving Decadal Changes In The Carbonate System Of A Coastal Plain Estuary: Associated Dataset, Fei Da, Marjorie A.M. Friedrichs, Pierre St-Laurent

Data

This dataset includes model outputs presented in the associated publication (Da et al. 2021, Journal of Geophysical Research: Oceans). This study used a three-dimensional ecosystem model to quantify the relative impacts of multiple anthropogenic drivers on the Chesapeake Bay carbonate system over the past three decades. Model simulations highlight that increased atmospheric CO₂ concentrations and decreased terrestrial nutrient inputs are two primary drivers causing nearly equal reductions in pH in surface waters of the Bay.

Sum Of Squares With Q-Series, Gosper’S Q- Trigonometry, An New Identities Via An Extended Bailey Transform, Zina Al Houchan

Theses

This report is concerned about q-series and some of their applications. Firstly, Jacobi’s q-series proof for Legendre’s theorem on sums of four squares will be presented. By way of comparison, the classical approach of this result will be also discussed. Secondly, Gosper’s q-trigonometry will be introduced using Jacobi’s theta functions and the theory of elliptic functions shall be employed to confirm one of Gosper’s conjectures. As an application, a proof for Fermat’s theorem on the sums of squares will be provided. Thirdly, an extended version of Bailey’s transform will be established and as a consequence, a variety of new q-series …

Powered By Ai, Christopher J. Smiley

The Journal of the Michigan Dental Association

Artificial Intelligence (AI) is revolutionizing dental practice through its ability to process vast amounts of data, enhance diagnosis, and improve patient care. However, AI introduces the challenge of bias and ethical considerations. Dentists and dental benefit providers are utilizing AI for early disease detection and efficient data management, but transparency and fairness in AI algorithms are vital. The Rome Call for AI Ethics emphasizes ethical, non-biased AI development. In the broader context, AI-driven marketing and predictive behavior raise concerns about privacy and ethical data use. The dental community must embrace AI's power while upholding ethical standards and transparency.

Sound In Color, Amber Rhodes

Honors Scholars Collaborative Projects

“Sound in Color” is an interactive audio-visual experience designed to explore the relationship between sound, color, and emotions. Taking place on the Massey Concert Hall stage, the project is inspired by synesthesia and incorporates research on color psychology. Participants are invited to select an emotion and color. As the user hums into a microphone, they hear their emotions expressed through sound in their headphones and watch as the lights on stage respond to their vocal cues.

One-Sided Derivative Of Distance To A Compact Set, Logan S. Fox, Peter Oberly, J. J. P. Veerman

Mathematics and Statistics Faculty Publications and Presentations

We give a complete and self-contained proof of a folklore theorem which says that in an Alexandrov space the distance between a point γ(t) on a geodesic γ and a compact set K is a right-differentiable function of t. Moreover, the value of this right-derivative is given by the negative cosine of the minimal angle between the geodesic and any shortest path to the compact set (Theorem 4.3). Our treatment serves as a general introduction to metric geometry and relies only on the basic elements, such as comparison triangles and upper angles.

Bert Argues: How Attention Informs Argument Mining, Ting Chen

Honors Theses

Argument mining is the automatic identification and extraction of structure from argumentative language. Previous works have constrained the argument structure to forming strictly trees in order to utilize efficient tree-specific techniques. However, arguments in the wild are unlikely to exhibit this constrained structure. Given the recent trend of fine-tuning large pre-trained models to reach state of the art performance on a variety of Natural Language Processing (NLP) tasks, we look to leverage the power of these deep contextualized word embeddings towards the task of non-tree argument mining. In this paper, we introduce a new pipeline which utilizes pre-trained BERT based …

Autocorrelation Infrasound Interferometry, Hugo D. Ortiz, Robin S. Matoza, Jeffrey B. Johnson, Stephen Hernandez, Juan C. Anzieta, Mario C. Ruiz

Geosciences Faculty Publications and Presentations

Seismic and infrasound multistation ambient‐noise interferometry has been widely used to infer ground and atmospheric properties, and single‐station and autocorrelation seismic interferometry has also shown potential for characterizing Earth structure at multiple scales. We extend autocorrelation seismic interferometry to ambient atmospheric infrasound recordings that contain persistent local noise from waterfalls and rivers. Across a range of geographic settings, we retrieve relative sound‐speed changes that exhibit clear diurnal oscillations consistent with temperature and wind variations. We estimate ambient air temperatures from variations in relative sound speeds. The frequency band from 1 to 2 Hz appears most suitable to retrieve weather parameters …

The Expansion Of A Native Generalist Species Following Competitive Release And Habitat Degradation, Ellie Tate

Senior Theses and Projects

The understanding of competitive release and a generalist species’ ability to exploit an available niche assists in explaining short- and long-term changes in ecological communities. I evaluated the expansion and establishment of a native generalist species, the red-eared slider (Trachemys scripta elegans), into a river community studied over a 50-year period (1969-2019). My objective was to analyze the T. s. elegans population upon expansion and how the population has been affected by the short- and long-term changes of the ecosystem. The turtle community in the North Fork of the White River, Ozark County, MO, USA faced habitat degradation, harvesting, a …

Does Defense Actually Win Championships? Using Statistics To Examine One Of The Greatest Stereotypes In Sports, Thomas Burkett

Senior Theses

A common saying in sports is that “defense wins championships.” However, the past decade of play in the modern NBA has seen a rise and focus in offensive efficiency and 3-pointers. This thesis tests whether defense can truly predict a championship winning team in today’s NBA through two-sample hypothesis testing and multiple logistic regression models. The results found that both defensive and offensive statistics were significant predictors of championship teams, meaning that a balanced team, rather than one specialized in defense alone, is a more accurate predictor of championship success.

Limit Theorems As Blessing Of Dimensionality: Neural-Oriented Overview, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

As a system becomes more complex, at first, its description and analysis becomes more complicated. However, a further increase in the system's complexity often makes this analysis simpler. A classical example is Central Limit Theorem: when we have a few independent sources of uncertainty, the resulting uncertainty is very difficult to describe, but as the number of such sources increases, the resulting distribution get close to an easy-to-analyze normal one -- and indeed, normal distributions are ubiquitous. We show that such limit theorems often make analysis of complex systems easier -- i.e., lead to blessing of dimensionality phenomenon -- for …

Selfish Gene Theory Explains Oedipus Complex, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

Sigmund Freud famously placed what he called Oedipus complex at the center of his explanation of psychological and psychiatric problems. Freund's analysis was based on anecdotal evidence and intuition, not on solid experiments -- as a result, for a long time, many psychologists dismissed the universality of Freud's findings. However, lately, experiments seem to confirm that indeed men, on average, select wives who resemble their mothers, and women select husbands who resemble their mothers. In this paper, we provide a possible biological explanation for this observational phenomenon.

What Is 1/0 From The Practical Viewpoint: A Pedagogical Note, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

What is 1/0? Students are first taught -- in elementary school -- that it is undefined, then -- in calculus -- then it is infinity. In both cases, the answer is usually provided based on abstract reasoning. But what about the practical meaning? In this paper, we show that, depending on the specific practical problem, we can have different answers to this question: in some practical problems, the correct answer is that 1/0 is undefined, in others, the correct answer is that 1/0 =0 -- and there are probably other practical problems where we can have different answers. Bottom line: …

Alaska Trip Geared To Support K-16 Climate Change Education Initiative, Joe Garvey

News Items

No abstract provided.

Bibliometric Analysis Of Named Entity Recognition For Chemoinformatics And Biomedical Information Extraction Of Ovarian Cancer, Vijayshri Khedkar, Charlotte Fernandes, Devshi Desai, Mansi R, Gurunath Chavan Dr, Sonali Tidke Dr., M. Karthikeyan Dr.

Library Philosophy and Practice (e-journal)

With the massive amount of data that has been generated in the form of unstructured text documents, Biomedical Named Entity Recognition (BioNER) is becoming increasingly important in the field of biomedical research. Since currently there does not exist any automatic archiving of the obtained results, a lot of this information remains hidden in the textual details and is not easily accessible for further analysis. Hence, text mining methods and natural language processing techniques are used for the extraction of information from such publications.Named entity recognition, is a subtask that comes under information extraction that focuses on finding and categorizing specific …

Implications Of Increased Sst On Sula Dactylatra In Rapa Nui Marine Park, Flavia Soctto D'Antuono, Hayden E. Dubniczki

Student Publications

Marine protected areas are a relatively new conservation tool intended to remove harmful anthropogenic practices and influences to enable ecological processes to occur normally, but they cannot protect ecosystems from global impacts like climate change. One such MPA, Rapa Nui Marine Park in Chile, is home to the Masked Booby, Sula dactylatra. Though not currently endangered, their population numbers decrease annually, and seabirds are among the most threatened species in the face of climate change. This study seeks to examine the spatial ecology of the Sula dactylatra against the context of the MPA and examines whether increasing sea surface temperatures …