Physical Sciences and Mathematics Commons^™

Optimizing Cluster Sets For The Scan Statistic Using Local Search, James Shulgan

Graduate Research Theses & Dissertations

In recent years, scattering sensors to produce wireless sensor networks (WSN) has been proposed for detecting localized events in large areas. Because sensor measurements are noisy, the WSN needs to use statistical methods such as the scan statistic. The scan statistic groups measurements into various clusters, computes a cluster statistic for each cluster, and decides that an event has happened if any of the statistics exceeds a threshold. Previous researchers have investigated the performance of the scan statistic to detect events; however, little attention was given to the optimization of which clusters the scan statistic should use. Using the scan …

Development Of Machine Learning Models To Predict The Online Impact Of Research, Mohammed Murtuza Shahzad Syed

Graduate Research Theses & Dissertations

Scientific research is being increasingly shared online in a way such that there is a need to develop methodologies to measure the impact of specific papers in ways that go beyond traditional indicators of scholarly citations and beyond the scholarly community. In this thesis, new machine learning models are developed to measure and predict the impact ofresearch in the online context. The extent to which research papers are mentioned on social media platforms, i.e., their online sustainability, indicates the public's interest in and perhaps even the level of understanding of scientific topics. A research paper having a long lifespan, i.e., …

Providing Better Choices: An Exploration Of Solutions In Multi-Objective Optimization And Game Theory Using Variational Analysis, Glenn Matthew Harris

Graduate Research Theses & Dissertations

Multi-objective optimization problems and game theory problems have a wide array of

applications and because of this there are different types of solutions available. This dissertation

explores two areas of optimization and a solution type for each. First, substantial

efficiency (SE) as a type of solution to multi-objective optimization problems that extends

proper efficiency. Secondly, strong Nash equilibria (SNE) as a type of solution to game

theoretic problems that extends Nash equilibria. Substantial efficiency is demonstrated to

be a superior solution to the more rudimentary notion of proper efficiency in solving some

multi-objective financial market and economic problems. Using this …

Tunable Refractive Index Through Spatially Modified Nanoparticle Films For Long-Range Spr Biosensing Applications, Stephen Joshua Binderup

Graduate Research Theses & Dissertations

Despite optics and refraction being among the oldest scientific principles, material limitations have prevented scientists from taking full advantage of the potential this technology holds. Indeed, films with designer optical properties have potential for use in exotic cloaking architectures, advanced waveguides, and precise optical biosensors. This thesis focuses on the fabrication methodology for making thin films with refractive index tuned to a desired value through self-assembly of amorphous nanoparticle films made of organosilicate materials. The inclusion of a slowly evaporating polymer phase along with the organosilicate nanoparticles results in nanopores formed within the film, which effectively reduce the film’s refractive …

Model-Based Network Reconstruction From Cascade Dynamics, Katherine Irena Chwistek

Graduate Research Theses & Dissertations

Network representation provides a natural framework for the study of real world complex systems. From social networks and animal groups to interneuronal communications and power grid systems, complex patterns of interaction can be captured and modeled using networks in a simple mathematical form. In many cases, however, a faithful network representation of the system is not readily available. For this reason, network reconstruction has become a growing topic of interest in recent years, the goal of which is to discover the hidden interaction patterns among individuals by fitting input-output data from multiple experiments to candidate network topologies.

During a cascade, …

The Emotions Of Science: Using Social Media To Gauge Public Emotions Toward Research Topics, Cole C. Freeman

Graduate Research Theses & Dissertations

Online and in the real world, communities are bonded together by emotional consensus around core issues. Emotional responses to scientific findings often play a pivotal role in these core issues. When there is too much diversity of opinion on topics of science, emotions flare up and give rise to conflict. This conflict threatens positive outcomes for research. Emotions have the power to shape how people process new information. They can color the public's understanding of science, motivate policy positions, even change lives. And yet little work has been done to evaluate the public's emotional response to science using quantitative methods. …

On Systematics And Their Mitigation In Magis-100 Atomic Interferometer Experiment To Explore The Dark Sector And Early Universe, Jeremiah Thomas Mitchell

Graduate Research Theses & Dissertations

Understanding the dark sector and early universe are of great importance to those in cosmology as well as physics in general. To probe these areas many large detector platforms and international experiments have come online to work in unison to test proposed models of dark matter and to provide direct detection of gravitational waves to explore what cannot be seen. Along these lines the Matter-wave Atomic Gradiometer and Interferometric Sensor (MAGIS-100) has set out to explore these fields of study using atom interferometry which provides a unique and scalable method for making sensitive measurements as well as being a test …

A Spider's Web Of Doughnuts, Daniel Stoertz

Graduate Research Theses & Dissertations

This dissertation studies an interplay between the dynamics of iterated quasiregular map-

pings and certain topological structures. In particular, the relationship between the Julia set

of a uniformly quasiregular mapping f : R 3 → R 3 and the fast escaping set of its associated

Poincaré linearizer is explored. It is shown that, if the former is a Cantor set, then the latter

is a spider’s web. A new class of uniformly quasiregular maps is constructed to which this

result applies. Toward this, a geometrically self-similar Cantor set of genus 2 is constructed.

It is also shown that for any …

Fundamental Study Of Supported Metal Catalysts Prepared By Metal In Lithium Solution For Energy Science, Haiping Xu

Graduate Research Theses & Dissertations

Electrochemical carbon dioxide reduction reaction (CO2RR) is a promising technique for energy conversion and storage from intermittent electricity sources (ie. wind and solar). By coupling electrochemical CO2 reduction (CO2R) to a renewable energy source atmospheric CO2 could be converted back into a fuel such as ethanol, or a commodity chemical such as ethanol or acetic acid. These products could then be consumed for energy or used to generate more valuable chemical products effectively removing CO2 from the atmosphere. To commercialize this process, it is highly desired to prepare catalysts that selectively reduce CO2 at low overpotential with long durability. Research …

Development Of An Electron-Beam Halo Diagnostics, Christopher James Marshall

Graduate Research Theses & Dissertations

Electron beam halos defined as the peripheral fraction of the beam that does not contribute to the front end application. Particles located in the halo can cause damage to the particle accelerator and lower the power and quality of the beam. Being able to measure the beam halo could provide insight on the halo-formation mechanism and ultimately will improve the overall performance and quality of the beam. A halo diagnostic was designed, and a prototype built and commissioned. The diagnostics relies on detecting optical radiation by the electron beam and masking its core to enhance the detection of the halo. …

Estimating Paleotemperatures In The Amundsen Sea For The Last 620,000 Years Through Diatom Morphometrics (Iodp Expedition 379), Joseph Robert Mastro

Graduate Research Theses & Dissertations

As global climate continues to rapidly change over the coming decades, West Antarctica will continue to be a significant area of concern due to its susceptibility to marine ice sheet collapse. Past collapses during Pleistocene interglacials have been hypothesized but uncertainty exists with respect to the precise timing of specific collapse events. Drill core samples collected from the Amundsen Sea continental rise during IODP Expedition 379 allow for analysis of a more continuous record of Pleistocene glacial-interglacial cycles. Here we report paleotemperature estimates from the Amundsen Sea spanning the last 620 kyr with the objective of identifying likely late Pleistocene …

Body Wave Analysis For Low-Angle Thrust Quakes On Titan: Implications For Dragonfly, John William Owens

Graduate Research Theses & Dissertations

Little is known of the structure and seismic nature of planetary bodies that have an outer shell of ice instead of a rocky crust. These bodies are called icy satellites and one such body, Saturn’s moon Titan, is unique because of its thick atmosphere, methane cycle, and assumed salty subsurface ocean. NASA’s Dragonfly mission, set to launch in 2026, will use a robotic rotorcraft to transport various instruments, including a seismometer, to the Shangri-La dune field on Titan. Until then, Titan’s seismic regime can be estimated by simulating wave propagation through assumed subsurface layers using source models. Ridge belts with …

Multi-Component Material For Solar Energy Conversion And Fundamentals Of Lead Acid Batteries, Crystal Ferels

Graduate Research Theses & Dissertations

Synthesis of complex inorganic materials is desirable because their complex composition allows more degrees of freedom and tunability, whose properties differ from their parent components. As an expansion on this concept, we synthesized a quinary compound Ce3FeWS3O6, using a molten flux method and a solvothermal method. The compound crystallizes into a hexagonal crystal system with space group P63/m. Its electric partition shows an anion with the form [(Ce3+)3W6+(S2-)3(O2-)6]3- forcing the transition metal Fe3+ state and leaving no conduction electrons, making the material a semiconductor. This compound is the right candidate as photoelectric material capable of absorbing photons from the solar …

Bayesian Approach To Finding The Most Likely Circuit Structure, Shannon Harms

Graduate Research Theses & Dissertations

Systems, and their reliabilities, depend on the reliabilities of the components that theyare composed of, and in this paper we want to nd the system structure that is the most likely given observed data. Bayesian methods were utilized in order to discover the posterior means, or observed reliabilities, of both the components and the systems. Assuming the serial and parallel system structures have independent components, we calculated system reliabilities based on observed component reliabilities by using the multiplication and addi- tion probability rules. We are then able to expand upon the numerical comparison method through a maximum likelihood analysis that …

Shape Tuning Of Silicon Nano-Tip Arrays Through Reactive Ion Etching For Cold Field Emission, Giridhar Tulasi Ram Sankabathula

Graduate Research Theses & Dissertations

Large area silicon nano-tip arrays have been predominantly used as cold cathode electron sources in the wide range of field emission applications. Various fabrication methodologies have been developed over the decades to obtain sharp-pointed field emitters. In this thesis, we mainly emphasized on reproducing high aspect ratio field emitters and to study their surface topographical changes encountered through reactive ion etching. A discrete set of high-density field emitters have been fabricated over the large area surfaces through a three-step nanofabrication process. The surface curvatures of the obtained emitter tips are finely tuned with multiple oxidation cycles to achieve a tip’s …

Cnn-Based Speed Detection Algorithm For Walking And Running Using Wrist-Worn Wearable Sensors, Venkata Devesh Reddy Seethi

Graduate Research Theses & Dissertations

In recent years, there have been a surge in ubiquitous technologies such as smartwatches and fitness trackers that can track human physical activities effortlessly. These devices have enabled common citizens to track their physical fitness and encourage them to lead a healthy lifestyle. Among various exercises, walking and running are the most common activities people do in everyday life, either through commute, exercise, or by doing household chores. While performing these activities, the speed at which a person walks and runs is an essential factor to determine the intensity of activity. Therefore, it is important to measure walking/running speed to …

Search For Higgs Pair Production In The Bbτ Τ Final State With The Atlas Detector At The Large Hadron Collider, Puja Saha

Graduate Research Theses & Dissertations

Abstract: This is a search for a Beyond Standard Model (BSM) heavy scalar in the ATLAS detector at 13 TeV center of mass energy using Run 2 data set recorded in 2018 with an integrated luminosity 58.5 fb^{-1}. The heavy scalar (X) decays to two Standard Model (SM) like light Higgs (H) bosons that decay into the bbtautau final state. Particularly, the semi-leptonic final state of two tau's is considered in this search where one tau decays in leptonic final state and other to a hadronic final state. No evidence of a new scalar found, so upper limits are set …

Real-Time Traffic Sign Detection And Classification Based On A Video Feed, Victor Ciuntu

Graduate Research Theses & Dissertations

Autonomous vehicle development is currently progressing at a very fast pace and traffic sign detection and classification has an important role in it. This thesis looks at the history of autonomous vehicles as well as different implementations for traffic sign detection and classification. Multiple possible approaches are analyzed with the final goal of doing this task in real-time using a portable system.

To accomplish this task, the final solution uses a convolutional neural network for detection and classification combined with a custom optical character recognition algorithm for speed limit signs. The optical character recognition algorithm is built from the ground …

Analysis Of Emissions Inventory Challenges Across The U.S. Supported By The Case Study Of Dekalb, Illinois, Using Clearpath, Emery Taylor Dhanens

Graduate Research Theses & Dissertations

The urgent need to address the destructive effects of climate change globally through mitigation and adaptation is clear. A useful tool for climate change mitigation is a greenhouse gas emissions inventory, which can be used to benchmark current emission levels and create future reduction goals. Emissions inventories in the United States are not currently required by the federal government, but many cities are nonetheless choosing to conduct these inventories and adopt greenhouse gas reduction goals. Inventory tools vary in terms of the methodologies behind emissions calculations, and previous studies have noted the comparability and consistency issue among inventories. This mixed-methods …

Copper And Gold In Vapors And Liquids As A Function Of Hcl At 700°C And 100 Mpa, Corrie A. Lucchesi

Graduate Research Theses & Dissertations

Porphyry ore deposits are major sources of copper (Cu) and gold (Au) and form when a magmatic volatile phase (MVP) exsolves from a porphyritic intermediate to felsic melt and transports metals to surrounding country rock where they precipitate in an ore zone. There is a consensus that the chloride concentration of the MVP has a direct relationship to the concentration of Cu and Au in the MVP, but the role of dissolved HCl on Cu and Au concentrations has not been addressed. It is hypothesized that increasing HCl concentrations in the MVP will result in higher concentrations of Cu and …

The Effect Of Self-Reflection On Relative Student Success In Undergraduate Calculus 1, Kevin Shryock

Graduate Research Theses & Dissertations

This thesis examines the effect of completion and self-reflection credit on multiple aspects of undergraduate student success in Calculus 1. Specifically, this study assessed the validity of a plug-and-play classroom framework utilizing a combination of a holistic rubric and corresponding worksheets to direct students’ attention towards their conceptual understanding of material and written work, all while removing the pressure of performance grades on all but four summative assessments. By comparing students’ relative performance on these summative assessments, as well as students’ responses on regular surveys, this study found that students who chose to forego performance grades in favor of completion …

A Search For Resonant And Non-Resonant Di-Higgs Production In The Γγbb Channel Using The Atlas Detector, Tyler James Burch

Graduate Research Theses & Dissertations

This dissertation presents a search for resonant and non-resonant di-Higgs production in the γγb ̄b final state using data from the ATLAS detector at the Large Hadron Collider (LHC). The search is performed on 36.1 fb−1 of data from proton-proton collisions at a center-of-mass energy of √s= 13 TeV collected in 2015 and 2016.

No significant excesses are observed in this search. The non-resonant analysis sets limits on the HH→γγb ̄b cross-section times branching ratio, with an upper observed (expected) limit of 0.73 (0.93) pb. The observed (expected) limits on the Higgs boson trilinear coupling at 95% Confidence Level (CL) …

An Automated Method For Detecting Water Levels Using Computer Vision And Artificial Intelligence, Priyanjani Chowdary Chandra

Graduate Research Theses & Dissertations

Flooding is one of the most dangerous weather events today. Between 2015-2019, on average, it has caused more than 130 deaths every year in the USA alone. World Health Organization has reported that, between 1998-2017, floods have affected more than 2 billion people worldwide. The devastating nature of flood necessitates the continuous monitoring of water level in the rivers and streams in flood-prone areas to detect the incoming flood. In this thesis, we have designed and implemented a computer vision and AI-based system that continuously detect the water level in the creek. Our solution employs an effective template matching algorithm …

Environmental Discriminators For Significant Tornadoes And Hail In The U.S. Using Proximity Soundings, Cody Michael Converse

Graduate Research Theses & Dissertations

Over the last 50 years, the United States has experienced an increase in severe storm events that produced $1 billion in damages or greater. Much of this loss is attributed to significant tornadoes and hail associated with deep, moist convection. Improving forecasts for these significant events assist in mitigating the impacts of these events. Previous work has identified statistically significant environmental parameters associated with severe thunderstorms, but more research is needed in identifying statistically significant ingredients associated with environments that produce significant tornadoes and hail.

This thesis aims to answer the following question: “Can diagnostics commonly used to forecast for …

Cobalt Partitioning And Solubility In Low-Temperature Carbonate-Hydrothermal Systems, Seth Kurtis Coursey

Graduate Research Theses & Dissertations

Cobalt mineralization has been documented in low temperature Mississippi Valley-type (MVT) deposits in southeast Missouri. Lead and zinc are the most economically important metals in these deposits and are contained within galena (PbS) and sphalerite (ZnS), respectively. Cobalt is also mined in some of the deposits with cobalt-bearing ores, e.g., siegenite ((Ni,Co)3S4) and fletcherite (Cu,(Ni,Co)2S4), occurring stratigraphically below main-stage galena and sphalerite. The hydrothermal fluids responsible for cobalt mineralization are thought to be chemically distinct from the predominant MVT ore-bearing fluids and represent a distinct mineralizing event. Cobalt is likely transported as CoCl2 in hydrothermal fluids and sourced from structures …

The Synthesis Of Pb2sr2sm1-Xcaxcu3o8 And Characterization Of Its Structural And Superconducting Properties., Deblina Das

Graduate Research Theses & Dissertations

Superconducting lead-based cuprate materials of the 2213 structural type, Pb2Sr2MCu3O8 (M=Sm1-xCax, Y1-xCax, Er1-xCax and Yb1-xCax), were synthesized and characterized using x-ray powder diffraction and the Rietveld structural refinements method. Pb2Sr2Sm1-xCaxCu3O8 single crystals were grown by an optimized flux method using various combinations of PbO/PbF2 solvents. Samples with different Sm/Ca ratios were investigated for their superconducting properties. Magnetic measurements reveal the presence of a transition at 120K. Preliminary x-ray diffuse scattering experiment at the Advanced Photon Source of Argonne National Laboratory demonstrates the high quality of one of our crystals and the presence of rod-like diffuse scattering connecting the Bragg peaks …

Projective Splitting Methods For Maximal Monotone Mappings In Hilbert Spaces, Oday Hazaimah

Graduate Research Theses & Dissertations

In this dissertation, novel approaches for solving convex nonsmooth optimization, variational inequalities and inclusion problems are studied. The main contributions of the dissertation are given in Chapter 4 and Chapter 5. The two proposed iterations in Chapter 4, Half-Extragradient algorithm (HEG) and its accelerated version, are a natural modification of the classical Extragradient algorithm (EG)

when the composite objective function is a sum of three convex functions. EG evaluates the smooth operator twice per iteration via proximal mappings, and also, it allows larger step sizes. One of the main advantages of the proposed scheme is to avoid evaluating an

extragradient …

Nonlinear Integrable Optics Beam Dynamics Experimentand Diagnostics, Sebastian Szustkowski

Graduate Research Theses & Dissertations

All present circular particle accelerators are built around linear focusing optics. Unavoidable nonlinear elements appear in accelerators, such as magnetic aberrations and space-charge effects, which are typically corrected using nonlinear magnets. However, these added nonlinearities degrade particle beam stability, and in most cases, the system becomes non-integrable. The Integrable Optics Test Accelerator (IOTA), at Fermi National Accelerator Laboratory (Fermilab), is a test bed to study beam dynamics in integrable lattices for both electron and proton beams, independently.This work presents experimental results of the nonlinear electron beam dynamics behavior in IOTA using an elliptical nonlinear magnet. The elliptical nonlinear magnet allows …

Wildlife Ecology And Conservation In A Suburban Preserve Matrix: Applications Of Long-Term Monitoring Data, John Peter Vanek

Graduate Research Theses & Dissertations

Wildlife is important to humans, offering economic, nutritional, ecological, and socio-cultural value. However, vertebrate biodiversity is being lost at rates 100 times greater than the background extinction rate, threatening human livelihood via the loss of ecosystem services. These human-induced species losses are primarily due to habitat destruction, which is increasingly tied to urban development. Conservation of wildlife resources is therefore imperative in a world where more than 50% of the human population, and 80% of people living in the United States, now live in urban areas. In this dissertation, I demonstrate how monitoring data can be applied to answer questions …

Model-Based Estimates Of The Timing Of Brine Flux Into The Victoria Land Basin From The Mcmurdo Dry Valleys, Antarctica, Valerie Nicole Voisin

Graduate Research Theses & Dissertations

Submarine groundwater discharge (SGD) at a continental scale is one of the least constrained components of the hydrologic cycle and may represent a significant flux of iron and silica waters to the global ocean. Quantifying SGD along the Antarctic margin is complicated by complex subglacial and subsurface hydrogeology and limited observational data. Airborne transient electromagnetic (AEM) surveys have identified extensive high-salinity subsurface brines in the McMurdo Dry Valleys (MDV) that are hydrologically connected to surface features in the MDV (e.g. Taylor Glacier, saline lakes) and are potentially a significant source of SGD to McMurdo Sound. A 2D numerical model was …