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Articles 1 - 30 of 106
Full-Text Articles in Physical Sciences and Mathematics
Error Handling Approaches In Programming Languages, Joey Aldrin Rees-Hill
Error Handling Approaches In Programming Languages, Joey Aldrin Rees-Hill
Honors Papers
Error handling is a part of nearly every computer program, but it is rarely the main focus of a program's developers. Nevertheless, correct error handling is important because it can enable a program to recover from abnormal circumstances and continue to function and serve its purpose. Programming languages offer a variety of tools and approaches for programs to detect and handle errors. I investigated the different approaches to error handling in contemporary programming languages. I found three general paradigms of error handling approaches. One paradigm was Special Return Value, in which certain return values of a function signify that an …
Characterizing Agn Influence On The Calculated Metallicities Of Adjacent Star-Forming Spaxels, Aidan Khelil
Characterizing Agn Influence On The Calculated Metallicities Of Adjacent Star-Forming Spaxels, Aidan Khelil
Honors Papers
In this thesis, I introduce a method to identify and characterize the effects of active galactic nuclei (AGN) on the spectra of nearby star-forming regions. I analyze spatially-resolved areas of galaxies called “spaxels” within Data Release 15 of the Sloan Digital Sky Survey (SDSS) with the goal of locating those which are physically close to AGN. I find those spaxels with calculated metallicities which lie adjacent to AGN-flagged spaxels and characterize their metallicity values relative to the spaxels which are not adjacent to AGN-flagged spaxels, using a total of 11 separate metallicity calibrations. I find that the current methods to …
Jacobi's Four Squares Theorem, Arman Yagci
Jacobi's Four Squares Theorem, Arman Yagci
Honors Papers
Jacobi’s Four Squares Theorem is a celebrated result of number theory that provides a formula for the number of ways a positive integer n can be written as a sum of four integral squares. In this paper, we prove this theorem using the theory of modular forms.
Contractible 4-Manifolds, Alexandra Du
Contractible 4-Manifolds, Alexandra Du
Honors Papers
Compact, contractible 4-manifolds distinct from D^4 were first constructed by Mazur and Poénaru. Sparks defined a collection of compact, contractible 4-manifolds called Jester manifolds. We study Mazur and Jester 4-manifolds. In particular, we show that all Jester manifolds are not homeomorphic to D^4, and that a collection of them are pairwise nonhomeomorphic.
Deep Reinforcement Learning For Open Multiagent System, Tianxing Zhu
Deep Reinforcement Learning For Open Multiagent System, Tianxing Zhu
Honors Papers
In open multiagent systems, multiple agents work together or compete to reach the goal while members of the group change over time. For example, intelligent robots that are collaborating to put out wildfires may run out of suppressants and have to leave the place to recharge; the rest of the robots may need to change their behaviors accordingly to better control the fires. Thus, openness requires agents not only to predict the behaviors of others, but also the presence of other agents. We present a deep reinforcement learning method that adapts the proximal policy optimization algorithm to learn the optimal …
Proper 3-Colorings Of Cycles And Hypercubes, Emily Cairncross
Proper 3-Colorings Of Cycles And Hypercubes, Emily Cairncross
Honors Papers
In this paper, we look at two families of graphs, cycles and hypercubes, and compare how their sets of proper 3-colorings differ as the graphs get arbitrarily large. In particular, we find the probability of pairs of vertices at various distances being the same color in order to understand the range and scale of interactions between them. As we look at larger and larger cycles, larger and larger hypercubes, patterns begin to emerge. While the colors of vertices fixed fractions of the cycle away from each other are independent, a random 3-coloring of the hypercube is essentially a 2-coloring. This …
Energy And Greenhouse Gas Savings For Leed-Certified U.S. Office Buildings Using Weighted Regression, Tian Liang
Energy And Greenhouse Gas Savings For Leed-Certified U.S. Office Buildings Using Weighted Regression, Tian Liang
Honors Papers
In this study, we studied the energy consumption and greenhouse gas emission performance of LEED-certified office buildings. We obtained the 2016 energy consumption and greenhouse gas emission data for 4002 office buildings from nine major US cities, including 522 buildings that we identified as LEED-certified. We discovered that LEED buildings used significantly more electricity percentagewise as their energy source. We also discovered that the locations and ages of buildings have significant effect on their performance. We removed the effect of locations and building ages using weighted regression. Our result showed that LEED office buildings used 11% less site energy, 9% …
The Mathematics Of Mutual Aid: Robust Welfare Guarantees For Decentralized Financial Organizations, Christian Ikeokwu
The Mathematics Of Mutual Aid: Robust Welfare Guarantees For Decentralized Financial Organizations, Christian Ikeokwu
Honors Papers
Mutual aid groups often serve as informal financial organizations that don’t rely on any central authority or legal framework to resolve disputes. Rotating savings and credit associations (roscas) are informal financial organizations common in settings where communities have reduced access to formal financial institutions. In a Rosca, a fixed group of participants regularly contribute small sums of money to a pool. This pool is then allocated periodically typically using lotteries or auction mechanisms. Roscas are empirically well-studied in the development economics literature. Due to their dynamic nature, however, roscas have proven challenging to examine theoretically. Theoretical analyses within economics have …
Petrology Of An Oxidized Blueschist Cobble From The San Onofre Breccia, California, Usa, Alaina A. Helm
Petrology Of An Oxidized Blueschist Cobble From The San Onofre Breccia, California, Usa, Alaina A. Helm
Honors Papers
The mid-Miocene San Onofre Breccia (SOB) found along the southern California borderlands contains clasts of several lithologies including high-pressure metamorphic rocks commonly thought to be shed from the Catalina Schist. Sorensen concluded the San Onofre Schist was part of the Franciscan Complex, although at that time the Catalina subduction was considered to be part of the Franciscan Complex. In this study, a ~10 cm cobble collected from the San Onofre type locality was studied to describe its mineralogy and estimate its conditions of metamorphism. The cobble is composed of glaucophane (35%) + epidote (15%) + garnet (13%) + phengite (12%) …
Increasing The Value Of Information During Planning In Uncertain Environments, Gaurab Pokharel
Increasing The Value Of Information During Planning In Uncertain Environments, Gaurab Pokharel
Honors Papers
Prior studies have demonstrated that for many real-world problems, POMDPs can be solved through online algorithms both quickly and with near optimality [10, 8, 6]. However, on an important set of problems where there is a large time delay between when the agent can gather information and when it needs to use that information, these solutions fail to adequately consider the value of information. As a result, information gathering actions, even when they are critical in the optimal policy, will be ignored by existing solutions, leading to sub-optimal decisions by the agent. In this research, we develop a novel solution …
Collaborative Game Mosaics, Xiaoyun Gong
Collaborative Game Mosaics, Xiaoyun Gong
Honors Papers
Imagine two players are playing a strategy board game. With one player holding black stones and the other player holding white stones, they take turns to place their pieces. After a while, they start to recognize some patterns. With three colors in front of them, black, white, and the color of the game board, they are curious about if they can form a recognizable image. Instead of playing the game to win, they start to collaborate with each other to form a mosaic. Later, they invite more players and provide them their own stones in different shades of gray. The …
Quality Of Sql Code Security On Stackoverflow And Methods Of Prevention, Robert Klock
Quality Of Sql Code Security On Stackoverflow And Methods Of Prevention, Robert Klock
Honors Papers
This paper explores the frequency at which SQL/PHP posts on the website Stackoverflow.com contain code susceptible to SQL Injection, a common database vulnerability. Specifically, we analyze whether other users give notice of the vulnerability or provide an answer that is secure. The majority of questions analyzed were vulnerable to SQL Injection and were not corrected in their answers or brought to the attention of the original poster. To mitigate this, we present a machine learning bot which analyzes the poster’s code and alerts them of potential injection vulnerabilities, if necessary.
Pretraining Deep Learning Models For Natural Language Understanding, Han Shao
Pretraining Deep Learning Models For Natural Language Understanding, Han Shao
Honors Papers
Since the first bidirectional deep learn- ing model for natural language understanding, BERT, emerged in 2018, researchers have started to study and use pretrained bidirectional autoencoding or autoregressive models to solve language problems. In this project, I conducted research to fully understand BERT and XLNet and applied their pretrained models to two language tasks: reading comprehension (RACE) and part-of-speech tagging (The Penn Treebank). After experimenting with those released models, I implemented my own version of ELECTRA, a pretrained text encoder as a discriminator instead of a generator to improve compute-efficiency, with BERT as its underlying architecture. To reduce the number …
Curving Towards Bézout: An Examination Of Plane Curves And Their Intersection, Camron Alexander Robey Cohen
Curving Towards Bézout: An Examination Of Plane Curves And Their Intersection, Camron Alexander Robey Cohen
Honors Papers
One area of interest in studying plane curves is intersection. Namely, given two plane curves, we are interested in understanding how they intersect. In this paper, we will build the machinery necessary to describe this intersection. Our discussion will include developing algebraic tools, describing how two curves intersect at a given point, and accounting for points at infinity by way of projective space. With all these tools, we will prove Bézout’s theorem, a robust description of the intersection between two curves relating the degrees of the defining polynomials to the number of points in the intersection.
Machine Learning? In My Election? It's More Likely Than You Think: Voting Rules Via Neural Networks, Daniel Firebanks-Quevedo
Machine Learning? In My Election? It's More Likely Than You Think: Voting Rules Via Neural Networks, Daniel Firebanks-Quevedo
Honors Papers
Impossibility theorems in social choice have represented a barrier in the creation of universal, non-dictatorial, and non-manipulable voting rules, highlighting a key trade-off between social welfare and strategy-proofness. However, a social planner may be concerned with only a particular preference distribution and wonder whether it is possible to better optimize this trade-off. To address this problem, we propose an end-to-end, machine learning-based framework that creates voting rules according to a social planner's constraints, for any type of preference distribution. After experimenting with rank-based social choice rules, we find that automatically-designed rules are less susceptible to manipulation than most existing rules, …
Courcelle's Theorem: Overview And Applications, Samuel Frederic Barr
Courcelle's Theorem: Overview And Applications, Samuel Frederic Barr
Honors Papers
Courcelle's Theorem states that any graph property expressible in monadic second order logic can be decidedin O(f(k)n) for graphs of treewidth k. This paper gives a broad overview of how this theorem is proved and outlines tools available to help express graph properties in monadic second order logic.
Asking Questions Is Easy, Asking Great Questions Is Hard: Constructing Effective Stack Overflow Questions, Jane W. Hsieh
Asking Questions Is Easy, Asking Great Questions Is Hard: Constructing Effective Stack Overflow Questions, Jane W. Hsieh
Honors Papers
This paper explores and seeks to improve the ways in which Stack Overflow question posts can elicit answers. Using statistical data analysis approaches and reviews of existing literature, we pin- point three key factors that are found in many previously success- ful/answerable questions. We then present a prototypical sidebar for the ask page that leverages these factors to dynamically (1) evaluate the quality of questions in construction (2) display answer previews of relevant questions and (3) scaffold the identified factors to subsequent askers during their question development processes.
General Game Playing As A Bandit-Arms Problem: A Multiagent Monte-Carlo Solution Exploiting Nash Equilibria, Brandon Mathewe Banda
General Game Playing As A Bandit-Arms Problem: A Multiagent Monte-Carlo Solution Exploiting Nash Equilibria, Brandon Mathewe Banda
Honors Papers
This project approaches general game playing in a unique way by combining popular methods of stochastic tree searching with a Multiagent system and a unique algorithm that I call the Wise Explorer algorithm. The goal of the system is to explore the worst possible branches of the game first to rule them out, followed by an in-depth search on the most promising branches. The system constantly refers to the data it collects during its extensive search, and it outputs a strategic move for any given state of a game. In essence, if you’re ever in a bind during a game …
The Molluscan Taphofacies Of And Influence Of Callianassid Shrimp On A Carbonate Lagoon (St. Croix, Us Virgin Islands), Rowan Lee
Honors Papers
Sediments collect in reef lagoons, and the shells within these can record changes in the environment as they accumulate. Smuggler’s Cove (St. Croix, USVI) has been accumulating a sediment package for at least 5,000 years based on radiocarbon ages. Callianassid shrimp severely bioturbate this lagoon’s sediment package by moving shell material into shelly, subsurface lags that have a high chance of becoming fossilized. Shell condition (taphonomy) was compared between surface and lag to see whether the lag is an accurate representation of the living surface fauna. Guild membership, taxon, and mollusk size between surface and lag assemblages were analyzed. It …
Dedekind Sums: Properties And Applications To Number Theory And Lattice Point Enumeration, Oliver Meldrum
Dedekind Sums: Properties And Applications To Number Theory And Lattice Point Enumeration, Oliver Meldrum
Honors Papers
In this paper, we will explore the origins, applications, and properties of these sums and one of their generalizations. We seek to explain what these sums represent and how they behave by exploring some of their arithmetic properties. In addition, we hope to show the reader why one should care about these sums. We do this by presenting two important areas in which these sums appear: number theory and the study of enumerating lattice points inside of polytopes.
A Gas Flow-Through System For Hydrogen Isotopic Separation With Metal-Organic Frameworks, Katharine Harp Rigdon
A Gas Flow-Through System For Hydrogen Isotopic Separation With Metal-Organic Frameworks, Katharine Harp Rigdon
Honors Papers
In this thesis, we designed and built a gas flow-through system to study dynamic adsorption separation of hydrogen isotopes in metal-organic frameworks (MOFs). MOFs are porous, crystalline materials composed of metal complexes connected by organic linkers. They have been proposed as a cheaper, more energy efficient approach to hydrogen isotope separation than current industrial methods. We have previously found evidence of a zero-point energy-based separation mechanism for hydrogen isotopes in two MOFs: Co-MOF-74 and Cu(I)-MFU-4l. This mechanism, chemical affinity quantum sieving (CAQS), has been extensively studied under static equilibrium conditions. The system in this work was developed so that CAQS …
Comparing Two Thickened Cycles: A Generalization Of Spectral Inequalities, Hannah E. Pieper
Comparing Two Thickened Cycles: A Generalization Of Spectral Inequalities, Hannah E. Pieper
Honors Papers
Motivated by an effort to simplify the Watts-Strogatz model for small-world networks, we generalize a theorem concerning interlacing inequalities for the eigenvalues of the normalized Laplacians of two graphs differing by a single edge. Our generalization allows weighted edges and certain instances of self loops. These inequalities were first proved by Chen et. al in [2] but our argument generalizes the simplified argument given by Li in [8].
Testing The Production Of Scintillation Arcs With The Pulsar B1133+16, Stella Koch Ocker
Testing The Production Of Scintillation Arcs With The Pulsar B1133+16, Stella Koch Ocker
Honors Papers
Pulsars are extremely dense, highly magnetized stars that emit pulses of radio emission every millisecond or so. The arrival times of their radio signals at Earth observatories can be used as a clock precise enough to detect gravitational waves. Performing such a detection requires the mitigation of interference effects from the interstellar medium: the slightly ionized, mostly hydrogen gas that the radio waves traverse as they travel from the pulsar to Earth. We investigate radio wave delays using a powerful tool: scintillation arcs, fluctuations in frequency and time of the pulsar signal intensity that are manifested as parabolic arcs in …
Generative Processes For Audification, Judith Jackson
Generative Processes For Audification, Judith Jackson
Honors Papers
Using the JavaSerial library, I present a generative method for the digital signal processing technique of audification. By analyzing multiple test instances produced by this method, I demonstrate that a generative audification process can be precise and easily controlled. The parameters tested in this experiment cause explicit, one-to-one changes in the resulting audio of each test instance.
Simulating Pulsar Signal Scattering In The Interstellar Medium With Two Distinct Scattering Phenomena, Adam P. Jussila
Simulating Pulsar Signal Scattering In The Interstellar Medium With Two Distinct Scattering Phenomena, Adam P. Jussila
Honors Papers
In this thesis, I discuss the creation of a simulation that attempts to reconstruct secondary spectra of pulsars by simulating the scattering in the interstellar medium. For the simulation, we focus on two distinct scattering phenomena, namely a coherent deflection at grazing incidence along a sheet of material, and a random deflection due to a random-walk type process through clouds of material. The simulation focuses on a representation known as a Wavefield Representation that our group has not utilized to this extent before, and it allowed us to understand the physics behind these scattering events in new depths. The final …
Hydrogen Isotope Separation In Metal-Organic Frameworks, Naiyuan Zhang
Hydrogen Isotope Separation In Metal-Organic Frameworks, Naiyuan Zhang
Honors Papers
In this thesis we present our research on hydrogen isotope separation using metal-organic frameworks (MOFs). Deuterium is one of the two stable isotopes of hydrogen. Despite its wide range of application, currently there is no ideal industrial method that can separate deuterium in a fast and efficient fashion. MOFs are a class of porous materials consisting of metal ions or clusters connected by organic ligands. They have shown great potential in separating hydrogen isotopes via quantum sieving effect. In this thesis, we first provide background on two state-of-art MOFs, Co-MOF-74 and Cu(I)-MFU-4l. Then we elaborate on the statistical theory of …
A Computational Introduction To Elliptic And Hyperelliptic Curve Cryptography, Nicholas Wilcox
A Computational Introduction To Elliptic And Hyperelliptic Curve Cryptography, Nicholas Wilcox
Honors Papers
At its core, cryptography relies on problems that are simple to construct but difficult to solve unless certain information (the “key”) is known. Many of these problems come from number theory and group theory. One method of obtaining groups from which to build cryptosystems is to define algebraic curves over finite fields and then derive a group structure from the set of points on those curves. This thesis serves as an exposition of Elliptic Curve Cryptography (ECC), preceded by a discussion of some basic cryptographic concepts and followed by a glance into one generalization of ECC: cryptosystems based on hyperelliptic …
Average Shortest Path Length In A Novel Small-World Network, Andrea J. Allen
Average Shortest Path Length In A Novel Small-World Network, Andrea J. Allen
Honors Papers
We study a novel model of random graph which exhibits the structural characteristics of the Watts- Strogatz small-world network. The small-world network is characterized by a high level of local clustering while also having a relatively small graph diameter. The same behavior that makes the Watts-Strogatz model behave like this also makes it difficult to analyze. Our model addresses this issue, closely mimicking the same structure experimentally while following a constructive process that makes it easier to analyze mathematically. We present a bound on the average shortest path length in our new model, which we approach by looking at the …
Artin Presentations And Closed 4-Manifolds, Jun Li
Artin Presentations And Closed 4-Manifolds, Jun Li
Honors Papers
In this paper we focus on the study of smooth closed simply-connected 4-manifolds. In particular, we study such manifolds arising from Artin presentations. Artin pre- sentations are intimately related to the pure braid group, and they characterize the fundamental groups of closed orientable 3-manifolds. Each Artin presentation r gives rise to a 4-manifold W4(r), whose boundary is a closed orientable 3-manifold M3(r) with fundamental group presented by r. In case the 4-manifold has bound- ary S3, we may close up W 4(r) by attaching a 4-handle to obtain W 4(r) ¿S3 D4. This closed 4-manifold has quadratic form represented by …
Glaciovolcanic Megapillows Of Undirhliðar, Reykjanes Peninsula, Southwestern Iceland, Rachel Heineman
Glaciovolcanic Megapillows Of Undirhliðar, Reykjanes Peninsula, Southwestern Iceland, Rachel Heineman
Honors Papers
At Undirhliðar tindar on the Reykjanes Peninsula, southwestern Iceland, megapillows are among the features formed during a series of ridge-building glaciovolcanic eruptions. Mapping of the northeastern 3 km of the ridge and petrographic and geochemical analysis of the megapillow outcrops occurring throughout this area demonstrate their role in the multi-stage construction of the ridge modeled by Pollock et al. (2014). The outcrops exhibit radial jointing, bands of vesicles and glassy rims, they occur in high relief surrounded by basalt breccia resembling pillow rubble, and are composed of plagioclase-phyric olivine basalt with plagioclase-rich groundmass. They occur in multiple pillow lava units …