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Full-Text Articles in Physical Sciences and Mathematics

Dipole Emission Characteristics Near A Topological Insulator Sphere Coated With A Metallic Nanoshell, Huai-Yi Xie, Railing Chang, P. T. Leung Apr 2021

Dipole Emission Characteristics Near A Topological Insulator Sphere Coated With A Metallic Nanoshell, Huai-Yi Xie, Railing Chang, P. T. Leung

Physics Faculty Publications and Presentations

Topological insulators (TI) are quantum states of (2D/3D) matter with an insulating interior but conducting edge/surface states, with these boundary conducting states being protected topologically by time-reversal symmetry. Composite materials of heavy atoms such as Bi2Te3 can be fabricated to show TI properties due to the strong intrinsic spin-orbit coupling of the electrons in these materials. Among the so many intriguing physical properties of these materials, their topological magneto-electric (TME) response is unique and has been studied intensively in the literature, leading to intriguing optical effects such as Faraday and Kerr rotations of incident polarized beams at …


One-Sided Derivative Of Distance To A Compact Set, Logan S. Fox, Peter Oberly, J. J. P. Veerman Apr 2021

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.


A Community Of Fear: Emotion And The Hydro-Social Cycle In East Porterville, California, Michael Egge, Idowu Ajibade Apr 2021

A Community Of Fear: Emotion And The Hydro-Social Cycle In East Porterville, California, Michael Egge, Idowu Ajibade

Geography Faculty Publications and Presentations

Broader governance challenges driving water insecurity globally are well documented in the literature, however the power-laden relationships and emotions that shape water access at the household and community levels are yet to be fully investigated, especially in the context of water consolidation projects. In this article, we examine the role of emotions in mediating access to water and in the production of resource struggles among marginalized communities, existing outside of conventional regulatory frameworks. We bring together two relational approaches – the hydro-social cycle and emotional political ecology – to examine water insecurity and how it manifests in the historically disadvantaged …


Learned Dual-View Reflection Removal, Simon Niklaus, Xuaner Cecilia Zhang, Jonathan T. Barron, Neal Wadhwa, Rahul Garg, Feng Liu, Tianfan Xue Apr 2021

Learned Dual-View Reflection Removal, Simon Niklaus, Xuaner Cecilia Zhang, Jonathan T. Barron, Neal Wadhwa, Rahul Garg, Feng Liu, Tianfan Xue

Computer Science Faculty Publications and Presentations

Traditional reflection removal algorithms either use a single image as input, which suffers from intrinsic ambiguities, or use multiple images from a moving camera, which is inconvenient for users. We instead propose a learning-based dereflection algorithm that uses stereo images as input. This is an effective trade-off between the two extremes: the parallax between two views provides cues to remove reflections, and two views are easy to capture due to the adoption of stereo cameras in smartphones. Our model consists of a learning-based reflection-invariant flow model for dual-view registration, and a learned synthesis model for combining aligned image pairs. Because …


Quantifying Biotic Voc Emissions From Moss: Air Quality Impacts Of Isoprene And Monoterpenes In Urban Environments, Danlyn L. Brennan Apr 2021

Quantifying Biotic Voc Emissions From Moss: Air Quality Impacts Of Isoprene And Monoterpenes In Urban Environments, Danlyn L. Brennan

University Honors Theses

Plant-derived biogenic volatile organic compound (VOC) emissions contribute to secondary emissions of molecules such as ground-level ozone (O3) and PM 2.5 which are known to be harmful to the environment and negatively impact human health. Currently, the most known biogenic VOC emissions are from vascular plants like trees and economically significant crops. Air quality models use known emission rates from these measurements and have many unknown sources yet to identify. Unknown values of emissions occur due to a lack of measurements of a wider variety of plants, especially that of smaller and lesser-studied species of bryophytes; mosses. This …


Spanning Trees Of Complete Graphs And Cycles, Minjin Enkhjargal Apr 2021

Spanning Trees Of Complete Graphs And Cycles, Minjin Enkhjargal

University Honors Theses

Spanning trees are typically used to solve least path problems for finding the minimal spanning tree of a graph. Given a number t ≥ 3 what is the least number n = α(t) such that there exists a graph on n vertices having precisely t spanning trees? Specifically, how will the factoring of t with the use of cycles connected by one vertex affect α(t)? Lower and upper bounds of α(t) are graphed by using properties of cycles and complete graphs. The upper bound of α(t) is then improved by constructing a graph of connected cycles {Cp1, C­ …


Multi-Institutional Study Of Self-Efficacy Within Flipped Chemistry Courses, Nicole Naibert, Kerry D. Duck, Michael M. Phillips, Jack Barbera Mar 2021

Multi-Institutional Study Of Self-Efficacy Within Flipped Chemistry Courses, Nicole Naibert, Kerry D. Duck, Michael M. Phillips, Jack Barbera

Chemistry Faculty Publications and Presentations

Active learning environments have been shown to be beneficial for student learning; however, including such activities can be limited by the class time available. One method that can provide more opportunities for active learning during face-to-face class time is the flipped learning approach. However, studies on the impacts of flipped learning environments on student motivation are limited. Therefore, in this multi-institutional study, general chemistry students enrolled in flipped courses at three institutions responded to measures of self-efficacy and self-regulatory strategies. The results from these measures were used to evaluate how students’ academic self-efficacy (ASE) and chemistry self-efficacy (CSE) changed over …


Tribal Revegetation Project Final Project Report: 92-Acre Area, Area 5 Radioactive Waste Management Complex, Nevada National Security Site, Nevada, Jeremy Spoon, Brittany Kruger, Richard Arnold, Kate Monti Barcalow, Tribal Revegetation Committee, Trc Mar 2021

Tribal Revegetation Project Final Project Report: 92-Acre Area, Area 5 Radioactive Waste Management Complex, Nevada National Security Site, Nevada, Jeremy Spoon, Brittany Kruger, Richard Arnold, Kate Monti Barcalow, Tribal Revegetation Committee, Trc

Anthropology Faculty Publications and Presentations

Nuwu (Southern Paiute), Newe (Western Shoshone), and Nuumu (Owens Valley Paiute) are linguistically related, Numic-speaking peoples who are part of the broader Uto-Aztecan language group. Numic peoples view the land as a holistic, living, sentient being with feelings and purpose. The land is personified with human characteristics and it needs to be experienced to be understood through “learning by doing.” Numic peoples do not support ground disturbing activities within their ancestral lands, including activities tied to the storage of low-level radioactive waste or classified materials on the NNSS, which they view as culturally inappropriate. These deep-rooted ancestral connections are the …


Molecules To Mountains: A Multi-Proxy Investigation Into Ancient Climate And Topography Of The Pacific Northwest, Usa, Alexander Mclean, John Bershaw Mar 2021

Molecules To Mountains: A Multi-Proxy Investigation Into Ancient Climate And Topography Of The Pacific Northwest, Usa, Alexander Mclean, John Bershaw

Geology Faculty Publications and Presentations

We characterize the topographic evolution of the Pacific Northwest, United States, during the Cenozoic. New paleosol carbonate stable isotope (δ18O) results from central Oregon are presented, along with published proxy data, including fossil teeth, smectites, and carbonate concretions. We interpret a polygenetic history of Cascade Mountain topographic uplift along-strike, characterized by: 1) Steady uplift of the Washington Cascades through the Cenozoic due long-term arc rotation and shortening against a Canadian buttress, and 2) Uplift of the Oregon Cascades to similar-to-modern elevations by the late Oligocene, followed by topographic stagnation as extension developed into the Neogene. Since the Miocene, meteoric water …


Evaluation Of Manual And Semi-Automated Deep-Seated Landslide Inventory Processes: Willapa Hills, Washington, Tiffany E. Justice Mar 2021

Evaluation Of Manual And Semi-Automated Deep-Seated Landslide Inventory Processes: Willapa Hills, Washington, Tiffany E. Justice

Dissertations and Theses

Recent advances in remote sensing data and technology have allowed for computational models to be designed that successfully extract landforms from the landscape. The goal of this work is to create one such semi-automated model to extract deep-seated landslides located in complex geomorphic terrain. This is accomplished using geographic object-based image analysis (GEOBIA) techniques, considered by leaders in the field of image analysis to have an advantage over traditional automated classification methods. GEOBIA methods can mimic human visual interpretation by including more characteristic features used to assess the relationship between image data and the ground surface such as color reflectance …


Glacier Clear Ice Bands Indicate Englacial Channel Microbial Distribution, Gilda Varliero, Alexandra Holland, Gary L. A. Barker, Marian L. Yallop, Andrew G. Fountain, Alexandre M. Anesio Mar 2021

Glacier Clear Ice Bands Indicate Englacial Channel Microbial Distribution, Gilda Varliero, Alexandra Holland, Gary L. A. Barker, Marian L. Yallop, Andrew G. Fountain, Alexandre M. Anesio

Geology Faculty Publications and Presentations

Distant glacial areas are interconnected by a complex system of fractures and water channels which run in the glacier interior and characterize the englacial realm. Water can slowly freeze in these channels where the slow freezing excludes air bubbles giving the ice a clear aspect. This ice is uplifted to the surface ablation zone by glacial movements and can therefore be observed in the form of clear surface ice bands. We employed an indirect method to sample englacial water by coring these ice bands. We were able, for the first time, to compare microbial communities sampled from clear (i.e. frozen …


Polymorphism And Polysemy In Images Of The Sefirot, Martin Zwick Mar 2021

Polymorphism And Polysemy In Images Of The Sefirot, Martin Zwick

Systems Science Faculty Publications and Presentations

The resurgence of interest in Kabbalistic diagrams (Segol, Busi, Chajes) raises the question of how diagrams function in religious symbolism. This question can be approached via methods used in the graphical modeling of data. Specifically, graph theory lets one define a repertoire of candidate structures that can be applied not only to quantitative data, but also to symbols consisting of qualitative components. A graph is a set of nodes and links between nodes. What nodes and links are is unspecified in this definition. The Kabbalistic Ilan is – partially – a graph. The Sefirot are its nodes; the paths connecting …


An Analysis Of Suspended Sediment Dynamics In A Partially Mixed Estuary, Riyadh Hamad Muttaleb Mar 2021

An Analysis Of Suspended Sediment Dynamics In A Partially Mixed Estuary, Riyadh Hamad Muttaleb

Dissertations and Theses

The purpose of this work is to investigate via data analysis and numerical modeling the SPM (suspended particulate matter) dynamics of a heavily contaminated partially urban estuary, the Lower Passaic River estuary (LPR), NJ. Accordingly, I investigate the quantity and mechanics of variation of fine and coarse SPM in the LPR via data analysis. Data analysis focuses on the parameters that affect SPM dynamics at six moored stations occupied during the Fall and Spring seasons, from near the estuary mouth to tidal freshwater. A 3D hydrodynamic model (Delft3D-FM) is used to analyze the effects of estuary topography on the dynamic …


Thermodynamics Of Ligand Binding And Global Structural Stability Of Human Serum Albumin, Matthew Walter Eskew Mar 2021

Thermodynamics Of Ligand Binding And Global Structural Stability Of Human Serum Albumin, Matthew Walter Eskew

Dissertations and Theses

Protein structure is integral to its function. For the past 70 years differential scanning calorimetry has been used to measure protein structural stability. More recently it has been used to study macromolecular interactions. Interactions between proteins and ligands can manifest on differential scanning calorimetry melting curves or thermograms. Utilizing differential scanning calorimetry thermograms to detect or diagnose diseases has been a major goal in disease diagnostics. However, correlating specific ligand-protein interactions, as manifested in a thermogram, with a disease-specific plasma thermogram, has proven elusive.

Modified human serum albumin was utilized to develop a process to capture and retrieve ligands from …


The Perceptions Of Rural Teachers Engaged In Environmental Education Professional Development Workshops: A Case Study Of The Alder Creek Community Forest And The Story Of Your Place, Bryan R. Benz Mar 2021

The Perceptions Of Rural Teachers Engaged In Environmental Education Professional Development Workshops: A Case Study Of The Alder Creek Community Forest And The Story Of Your Place, Bryan R. Benz

Dissertations and Theses

Environmental issues can be difficult for people to understand and for teachers to address in their classrooms. Issues such as climate change and ozone depletion are difficult to comprehend and present a challenge for most people to understand thoroughly the complexity of these environmental challenges. Professional development programs could provide the tools for teachers to improve their environmental literacy and a pathway for learning new methods for engaging their students. However, in rural Oregon, where professional development opportunities are scarce, teachers rely on a lean supply of organizations to provide these experiences. Alder Creek Community Forest, a nonprofit organization, provides …


Complex Fluid Dynamics: Chemo-Hydrodynamics Driven By Autocatalytic Reaction Fronts, Matthew Walter Eskew Mar 2021

Complex Fluid Dynamics: Chemo-Hydrodynamics Driven By Autocatalytic Reaction Fronts, Matthew Walter Eskew

Dissertations and Theses

Chemo-hydrodynamics generated from reaction-diffusion-convection processes of autocatalytic chemical systems are extensively studied for their applications in modeling complex systems. Compared to the more extensively studied autocatalytic systems, chlorite-tetrathionate and chlorite-trithionate, the chlorite-thiourea systems is relatively unexplored. Compared to the two previous systems, chlorite-thiourea has more straightforward chemical kinetics. To narrow the gap between chlorite-thiourea and the other systems a combination of experimental study and numerical simulation were employed to quantify this system.

Compared to established literature, experiments were performed at five orders of magnitude lower concentration of indicator, minimizing confounding effects of indicator on hydrodynamic motion. To accurately image the …


Pacific Northwest Littoral Data, Curt D. Peterson, Kara E. P. Kingen Mar 2021

Pacific Northwest Littoral Data, Curt D. Peterson, Kara E. P. Kingen

Geology Faculty Datasets

This document contains five data tables in PDF file formats, that are used to characterize littoral subcell (beach, river mouth, and inner-shelf) conditions in the Pacific Northwest (PNW) region (Washington, Oregon, and Northern California). These data have been compiled from pre-existing data sets (see citations in Table notes and References, below) for the purposes of predicting possible beach erosion from potential future sea level rise (SLR), as introduced in Kingen (2018) and Peterson et al. (2019, 2020a,b). The five data tables include Heavy-mineral tracers (Table 1), Heavy-mineral data (normalized) (Table 2), Subcell beach profile settings (Table 3), Subcell beach profile …


Inferring The Subsurface Geometry And Strength Of Slow-Moving Landslides Using 3-D Velocity Measurements From The Nasa/Jpl Uavsar, Alexander L. Handwerger, Adam M. Booth, Mong-Han Huang, Eric J. Fielding Mar 2021

Inferring The Subsurface Geometry And Strength Of Slow-Moving Landslides Using 3-D Velocity Measurements From The Nasa/Jpl Uavsar, Alexander L. Handwerger, Adam M. Booth, Mong-Han Huang, Eric J. Fielding

Geology Faculty Publications and Presentations

The hazardous impact and erosive potential of slow‐moving landslides depends on landslide properties including velocity, size, and frequency of occurrence. However, constraints on size, in particular, subsurface geometry, are lacking because these types of landslides rarely fully evacuate material to create measurable hillslope scars. Here, we use pixel offset tracking with data from the NASA/JPL Uninhabited Aerial Vehicle Synthetic Aperture Radar to measure the three‐dimensional surface deformation of 134 slow‐moving landslides in the northern California Coast Ranges. We apply volume conservation to infer the actively deforming thickness, volume, geometric scaling, and frictional strength of each landslide. These landslides move at …


Evaluating A Commercially Available In-Duct Bipolar Ionization Device For Pollutant Removal And Potential Byproduct Formation, Yicheng Zeng, Prashik Manwatkar, Aurelie Laguerre, Marina Beke, Insung Kang, Akram S. Ali, Delphine K. Farmer, Elliott T. Gall, Mohammad Heidarinejad, Brent Stephens Mar 2021

Evaluating A Commercially Available In-Duct Bipolar Ionization Device For Pollutant Removal And Potential Byproduct Formation, Yicheng Zeng, Prashik Manwatkar, Aurelie Laguerre, Marina Beke, Insung Kang, Akram S. Ali, Delphine K. Farmer, Elliott T. Gall, Mohammad Heidarinejad, Brent Stephens

Mechanical and Materials Engineering Faculty Publications and Presentations

We conducted a series of experiments to evaluate the gas and particle removal effectiveness and potential for byproduct formation resulting from the operation of a commercially available in-duct bipolar ionization device. Laboratory tests were conducted with the ionizer installed in a small air handler serving a large semi-furnished chamber. Chamber experiments were conducted under (i) normal operating conditions to characterize the impact of the ionizer on concentrations of particles (0.01–10 μm), ozone (O3), nitrogen dioxide (NO2), volatile organic compounds (VOCs), and aldehydes, and (ii) particle injection and decay conditions to characterize the impact of the ionizer operation on particle loss …


Altimetry For The Future: Building On 25 Years Of Progress, Saleh Abdalla, Abdolnabi Kolahchi, Micheal Ablain, Susheel Adusumilli, Suchandra Aich Bhowmick, Eva Alou-Font, Laiba Amarouche, Ole Baltazar Andersen, Edward Zaron, Multiple Additional Authors Mar 2021

Altimetry For The Future: Building On 25 Years Of Progress, Saleh Abdalla, Abdolnabi Kolahchi, Micheal Ablain, Susheel Adusumilli, Suchandra Aich Bhowmick, Eva Alou-Font, Laiba Amarouche, Ole Baltazar Andersen, Edward Zaron, Multiple Additional Authors

Civil and Environmental Engineering Faculty Publications and Presentations

In 2018 we celebrated 25 years of development of radar altimetry, and the progress achieved by this methodology in the fields of global and coastal oceanography, hydrology, geodesy and cryospheric sciences. Many symbolic major events have celebrated these developments, e.g., in Venice, Italy, the 15th (2006) and 20th (2012) years of progress and more recently, in 2018, in Ponta Delgada, Portugal, 25 Years of Progress in Radar Altimetry. On this latter occasion it was decided to collect contributions of scientists, engineers and managers involved in the worldwide altimetry community to depict the state of altimetry and propose recommendations for the …


Group Theory Visualized Through The Rubik's Cube, Ashlyn Okamoto Feb 2021

Group Theory Visualized Through The Rubik's Cube, Ashlyn Okamoto

University Honors Theses

In my thesis, I describe the work done to implement several Group Theory concepts in the context of the Rubik’s cube. A simulation of the cube was constructed using Processing-Java and with help from a YouTube series done by TheCodingTrain. I reflect on the struggles and difficulties that came with creating this program along with the inspiration behind the project. The concepts that are currently implemented at this time are: Identity, Associativity, Order, and Inverses. The functionality of the cube is described as it moves like a regular cube but has extra keypresses that demonstrate the concepts listed. Each concept …


Alpine Ice-Core Evidence Of A Large Increase In Vanadium And Molybdenum Pollution In Western Europe During The 20th Century, Monica M. Arienzo, Michel Legrand, Susanne Preunkert, Andreas Stohl, Nathan Chellman, Sabine Eckhardt, Kelly E. Gleason, Joseph R. Mcconnell Feb 2021

Alpine Ice-Core Evidence Of A Large Increase In Vanadium And Molybdenum Pollution In Western Europe During The 20th Century, Monica M. Arienzo, Michel Legrand, Susanne Preunkert, Andreas Stohl, Nathan Chellman, Sabine Eckhardt, Kelly E. Gleason, Joseph R. Mcconnell

Environmental Science and Management Faculty Publications and Presentations

Pollutants emitted by industrial processes are deposited across the landscape. Ice core records from mid‐latitude glaciers located close to emission sources document the history of local‐to‐regional pollution since preindustrial times. Such records underpin attribution of pollutants to specific emission sources critical to developing abatement policies. Previous ice core studies from the Alps document the overall magnitude and timing of pollution related to nitrogen and sulfur‐derived species, as well as a few metals including lead. Here, we used subannually resolved measurements of vanadium (V) and molybdenum (Mo) in two ice cores from Col du Dome (French Alps), as well as atmospheric …


Using The Gouy Phase Anomaly To Localize And Track Bacteria In Digital Holographic Microscopy 4d Images, True Gibson, Manuel Bedrossian, Eugene Serabyn, Chris Lindensmith, Jay Nadeau Feb 2021

Using The Gouy Phase Anomaly To Localize And Track Bacteria In Digital Holographic Microscopy 4d Images, True Gibson, Manuel Bedrossian, Eugene Serabyn, Chris Lindensmith, Jay Nadeau

Physics Faculty Publications and Presentations

Described over 100 years ago, the Gouy phase anomaly refers to the additional π phase shift that is accumulated as a wave passes through focus. It is potentially useful in analyzing any type of phase-sensitive imaging; in light microscopy, digital holographic microscopy (DHM) provides phase information in the encoded hologram. One limitation of DHM is the weak contrast generated by many biological cells, especially unpigmented bacteria. We demonstrate here that the Gouy phase anomaly may be detected directly in the phase image using the z-derivative of the phase, allowing for precise localization of unlabeled, micrometer-sized bacteria. The use of dyes …


The Influence Of Spaceflight And Simulated Microgravity On Bacterial Motility And Chemotaxis, Jacqueline Acres, Myka Jaap Youngapelian, Jay Nadeau Feb 2021

The Influence Of Spaceflight And Simulated Microgravity On Bacterial Motility And Chemotaxis, Jacqueline Acres, Myka Jaap Youngapelian, Jay Nadeau

Physics Faculty Publications and Presentations

As interest in space exploration rises, there is a growing need to quantify the impact of microgravity on the growth, survival, and adaptation of microorganisms, including those responsible for astronaut illness. Motility is a key microbial behavior that plays important roles in nutrient assimilation, tissue localization and invasion, pathogenicity, biofilm formation, and ultimately survival. Very few studies have specifically looked at the effects of microgravity on the phenotypes of microbial motility. However, genomic and transcriptomic studies give a broad general picture of overall gene expression that can be used to predict motility phenotypes based upon selected genes, such as those …


Public Perceptions Of Ocean Health And Marine Protection: Drivers Of Support For Oregon’S Marine Reserves, Paul Manson, Max Nielsen-Pincus, Elise F. Granek, Thomas C. Swearingen Feb 2021

Public Perceptions Of Ocean Health And Marine Protection: Drivers Of Support For Oregon’S Marine Reserves, Paul Manson, Max Nielsen-Pincus, Elise F. Granek, Thomas C. Swearingen

Environmental Science and Management Faculty Publications and Presentations

Over the past several decades marine conservation policy has supported the implementation of protected areas in ocean and coastal environments to restrict some elements of human use for ecological benefits. The appropriate extent of protection and the allowable uses are often the subject of public debate about marine protected area policy. Local community dynamics around marine protected area designation and management have been the subject of much ocean and coastal management social science research. However, broader public opinions and attitudes about marine protected areas are not well understood and are critical for managers seeking to maintain their public trust obligations …


Distribution And Antibiotic Resistance Profiles Of Salmonella Enterica In Rural Areas Of North Carolina After Hurricane Florence In 2018, Yuqing Mao, Mohamed Zeineldin, Moiz Usmani, Sital Uprety, Joanna Shisler, Antarpreet Jutla, Avinash Unnikrishnan, Thanh H. Nguyen Feb 2021

Distribution And Antibiotic Resistance Profiles Of Salmonella Enterica In Rural Areas Of North Carolina After Hurricane Florence In 2018, Yuqing Mao, Mohamed Zeineldin, Moiz Usmani, Sital Uprety, Joanna Shisler, Antarpreet Jutla, Avinash Unnikrishnan, Thanh H. Nguyen

Civil and Environmental Engineering Faculty Publications and Presentations

The frequency and magnitude of extreme events are increasing globally (Arnell & Gosling, 2016). Inundation, as a result of massive flooding, has the potential to change environmental conditions abruptly, and as a result, add pressure to the metabolism and proliferation of microorganisms (Furtak et al., 2020). The resulting overland flows and additional burden from domestic sewer and septic tank systems during an extreme flood event can introduce pathogens into ecologically unstable water bodies. For example, Yu et al. (2018) reported elevated levels of Escherichia coli and antibiotic resistance genes (ARGs) in river water samples 6 months after flooding in Houston, …


Forecasting Optimal Parameters Of The Broken Wing Butterfly Option Strategy Using Differential Evolution, David Munoz Constantine Jan 2021

Forecasting Optimal Parameters Of The Broken Wing Butterfly Option Strategy Using Differential Evolution, David Munoz Constantine

Dissertations and Theses

Obtaining an edge in financial markets has been the objective of many hedge funds, investors, and market participants. Even with today's abundance of data and computing power, few individuals achieve a consistent edge over an extended time. To obtain this edge, investors usually use options strategies. The Broken Wing Butterfly (BWB) is an options strategy that has increased in popularity among traders. Profit is generated primarily by exploiting option value time decay. In this thesis, the selection of entry and exit BWB parameters, such as profit and loss targets, are optimized for an in-sample period. Afterward, they are used to …


Niche Partitioning Of Low-Light Adapted Prochlorococcus Subecotypes Across Oceanographic Gradients Of The North Pacific Subtropical Front, Anne W. Thompson, Kathleen Kouba, Nathan A. Ahlgren Jan 2021

Niche Partitioning Of Low-Light Adapted Prochlorococcus Subecotypes Across Oceanographic Gradients Of The North Pacific Subtropical Front, Anne W. Thompson, Kathleen Kouba, Nathan A. Ahlgren

Biology Faculty Publications and Presentations

The cyanobacterium Prochlorococcus is the most abundant photosynthetic cell on Earth and contributes to global ocean carbon cycling and food webs. Prochlorococcus is known for its extensive diversity that falls into two groups of ecotypes, the low‐light (LL) and high‐light (HL) adapted ecotypes. Previous work has shown niche partitioning of the very abundant HL adapted ecotypes and subecotypes across oceanographic gradients including temperature, nutrients, and day length. However, niche partitioning of subecotypes within the LL adapted ecotypes has not been studied as well because they are less abundant and less accessible than surface, HL populations. Through high‐throughput, cyanobacterial‐specific, sequencing of …


Automated Test Generation For Validating Systemc Designs, Bin Lin Jan 2021

Automated Test Generation For Validating Systemc Designs, Bin Lin

Dissertations and Theses

Modern system design involves integration of all components of a system on a single chip, namely System-on-a-Chip (SoC). The ever-increasing complexity of SoCs and rapidly decreasing time-to-market have pushed the design abstraction to the electronic system level (ESL), in order to increase design productivity. SystemC is a widely used ESL modeling language that plays a central role in modern SoCs design process. ESL SystemC designs usually serve as executable specifications for the subsequent SoCs design flow. Therefore, undetected bugs in ESL SystemC designs may propagate to low-level implementations or even final silicon products. In addition, modern SoCs design often involves …


Stability Conditions For Coupled Autonomous Vehicles Formations, Pablo Baldivieso, J. J. P. Veerman Jan 2021

Stability Conditions For Coupled Autonomous Vehicles Formations, Pablo Baldivieso, J. J. P. Veerman

Mathematics and Statistics Faculty Publications and Presentations

In this paper, we give necessary conditions for stability of coupled autonomous vehicles in R. We focus on linear arrays with decentralized vehicles, where each vehicle interacts with only a few of its neighbors. We obtain explicit expressions for necessary conditions for stability in the cases that a system consists of a periodic arrangement of two or three different types of vehicles, i.e. configurations as follows: 2-1-2-1 or 3-2-1-3-2-1. Previous literature indicated that the (necessary) condition for stability in the case of a single vehicle type (1-1-1) held that the first moment of certain coefficients of the interactions between vehicles …