Physical Sciences and Mathematics Commons^™

Equilibrium Analysis For An Epidemic Model With A Reservoir For Infection, Istvan Lauko, Gabriella Pinter, Rachel Elizabeth Tewinkel

Mathematical Sciences Student Articles

We consider a system of non-linear differential equations describing the spread of an epidemic in two interacting populations. The model assumes that the epidemic spreads within the first population, which in turn acts as a reservoir of infection for the second population. Weexplore the conditions under which the epidemic is endemic in both populations and discuss the global asymptotic stability of the endemic equilibrium using a Lyapunov function and results established for asymptotically autonomous systems. We discuss monkeypox as an example of an emerging disease that can be modelled in this way and present some numerical results representing the model …

A Microscopic Simulation Laboratory For Evaluation Of Off-Street Parking Systems, Yun Yuan

Theses and Dissertations

The parking industry produces an enormous amount of data every day that, properly analyzed, will change the way the industry operates. The collected data form patterns that, in most cases, would allow parking operators and property owners to better understand how to maximize revenue and decrease operating expenses and support the decisions such as how to set specific parking policies (e.g. electrical charging only parking space) to achieve the sustainable and eco-friendly parking.

However, there lacks an intelligent tool to assess the layout design and operational performance of parking lots to reduce the externalities and increase the revenue. To address …

River Bank Inducement Influence On A Shallow Groundwater Microbial Community And Its Effects On Aquifer Reactivity, Natalie June Gayner

Theses and Dissertations

Placing groundwater wells next to riverbanks to draw in surface water, known as riverbank inducement (RBI), is common and proposed as a promising and sustainable practice for municipal and public water production across the globe. However, these systems require further investigation to determine risks associated with river infiltration especially with rivers containing wastewater treatment plant (WWTP) effluent. Since microbes drive biogeochemical transformations in groundwater and largely affect water quality, it is important to understand how the microbial communities in drinking water wells are affected by river infiltration. This study investigated if, and to what extent, the microbial community in a …

The Built Landscape And Ecological Behavior: Patterns For Readdressing Environmental Thinking In Residence Hall Design, Sarah Keogh

Theses and Dissertations

This research addresses how architectural design processes and practices are implicated and/or reflected in social constructions of ecological thinking. It is generally recognized that human behaviors are affecting climate change and giving rise to a plethora of ecological issues; yet a transformation of widespread behavior has not yet followed. This raises questions. In the field of architecture, how can the built landscape function to encourage and support sustainable behavior patterns?

Looking at universities as locations that are embedded in their urban contexts and have influence both on their surrounding communities and on year after year of students who pass through, …

Graphene-Based Materials Coated On Zeolite For The Removal Of Persistent Organic Pollutants From Water, Yan Zhang

Theses and Dissertations

Adsorption is a fast, low-cost and the most commonly implemented water treatment technology for the removal of multiple contaminations from ground water, drinking water or wastewater. Difficulties in removing persistent organic pollutants (POPs) to improve quality and safety of treated water sources require the exploration of novel and multifunctional materials. Graphene-based materials having unique structures, high specific surface areas and tailorable functional groups are promising candidates as adsorbents.

The main goal of this work is to fabricate a novel adsorbent made of GO/rGO attached on natural zeolite substrates for the removal of variably charged organic model compounds and POPs in …

Shorter And Improved Access To The Key Tetracyclic Core Of Sarpagine-Macroline-Ajmaline Indole Alkaloids: The Total Synthesis Of Alkaloids Macrocarpines A-G, Talcarpine, N(4)-Methyl-N(4),21-Secotalpinine, Deoxyperaksine, Dihydroperaksine, Talpinine, O-Acetyltalpinine, And N(4)-Methyltalpinine, Md Toufiqur Rahman

Theses and Dissertations

Extension of the asymmetric Pictet-Spengler (P-S) reaction to bulkier Nb-alkylated tryptophan derivatives resulted in a shorter and improved stereospecific access to the key bicyclo[3.3.1]nonane framework of bioactive C-19 methyl substituted sarpagine/macro-line/ajmaline indole alkaloids with excellent diastereoselectivity via internal asymmetric induction. The asymmetric Pictet-Spengler/Dieckmann protocol with bulky Nb-alkyl substituted systems enabled a more direct and two-step shorter route to this key architecture. Complete stereocontrol of the C-19 methyl function in either the α- or β-configuration was achieved which would enable one to gain rapid access to the crucial intermediates for the total synthesis of any member of this group of seventy …

Multi-Base Chains For Faster Elliptic Curve Cryptography, Saud Al Musa

Theses and Dissertations

This research addresses a multi-base number system (MBNS) for faster elliptic curve cryptography (ECC). The emphasis is on speeding up the main operation of ECC: scalar multiplication (tP). Mainly, it addresses the two issues of using the MBNS with ECC: deriving optimized formulas and choosing fast methods. To address the first issue, this research studies the optimized formulas (e.g., 3P, 5P) in different elliptic curve coordinate systems over prime and binary fields. For elliptic curves over prime fields, affine Weierstrass, Jacobian Weierstrass, and standard twisted Edwards coordinate systems are reviewed. For binary elliptic curves, affine, Lambda-projective, and twisted mu4-normal coordinate …

Concurrency Analysis In Javascript Programs Using Arrows, Joshua Cochrane

Theses and Dissertations

Concurrency errors are difficult to detect and correct in asynchronous programs such as those implemented in JavaScript. One reason is that it is often difficult to keep track of which parts of the program may execute in parallel and potentially share resources in unexpected, and perhaps unintended, ways. While programming constructs such as promises can help improve the readability of asynchronous JavaScript programs that were traditionally written using callbacks, there are no static tools to identify asynchronous functions that run in parallel, which may potentially cause concurrency errors.

In this work, we present a solution for implementing JavaScript programs using …

Conversion Of A Simulator Written In C++ To Js And Optimizing The Simulation Parameters Using Evolutionary Algorithms, Venkata Sivasai Pavan Kumar Lottala

Theses and Dissertations

A discrete event simulator written in C++ is converted in to Java Script, that tracks the

blood glucose level of a person in response to a timed sequence of diet and exercise activities. Its

main objective is to capture the average impact of the various diet/exercise activities on the blood

glucose level. The main aim for translation of the code in to Java Script is that the simulator can

be hosted on the Google Firebase Cloud and can be available for the public use. The optimization

of the simulator parameters such as excretionKidney_impact, glut4Impact_,

glycolysisMinImpact_, gngImpact_, peakinsulinLevel_, glycolysisMaxImpact_,

liverGlycogenBreakdownImpact_ and …

Multidecadal Variability In Climate Models And Observations, Alex Carl Oser

Theses and Dissertations

Climate change attribution and prediction using state-of-the-art models continue to garner an ever-growing focus amongst both the scientific community and public alike. Recent analyses showing discrepancies in the structure of modeled and observed decadal climate variability (DCV), therefore, have engendered efforts to not only diagnose the dynamics underpinning observed DCV, but also to characterize the behavior of DCV within climate models. In this thesis, we employ Multichannel Singular Spectrum Analysis (M-SSA) to show that while the DCV signal in observations is best described as a coherent oscillation with complex propagation across the globe, modeled DCV lacks this structure altogether. Specifically, …

The Strong Law Of Large Numbers For U-Statistics Under Random Censorship, Jan Höft

Theses and Dissertations

We introduce a semi-parametric U-statistics estimator for randomly right censored data. We will study the strong law of large numbers for this estimator under proper assumptions about the conditional expectation of the censoring indicator with re- spect to the observed life times. Moreover we will conduct simulation studies, where the semi-parametric estimator is compared to a U-statistic based on the Kaplan- Meier product limit estimator in terms of bias, variance and mean squared error, under different censoring models.

Dynamic Pricing With Variable Order Sizes For A Model With Constant Demand Elasticity, Nyles Kirk Breecher

Theses and Dissertations

We investigate a dynamic pricing model under constant demand elasticity which accounts for customers ordering multiple items at once. A closed form expression for the optimal expected revenue and pricing strategy is found. Models with the same demand are shown to have asymptotically similar expected revenue and pricing strategies, even if the order size distributions of the customers are different. Surprisingly, the relative difference between comparable models is shown to be independent of time and the magnitude of demand. Variations of the model are considered, including different low inventory behavior as well as the effect of advertising. Some numerical simulations …

Triebel-Lizorkin Spaces Estimates For Evolution Equations With Structure Dissipation, Jingchun Chen

Theses and Dissertations

This work is concerned with the long time decay estimates of the generalized heat equations and the generalized wave equations in the homogeneous Triebel-Lizorkin spaces. We first extend the known results for the generalized heat equations in the real Hardy spaces. We also extend the known results for the generalized wave equations with structure dissipation in the real Hardy spaces.

The main tools employed are the decomposition of the unit, duality property in Triebel-Lizorkin spaces and the multiplier theorems in different function spaces such as Lebesgue spaces, real Hardy spaces and Triebel-Lizorkin spaces.

Analyzing Ductile Shear Zone Network Geometries In The Grassy Portage Sill, Rainy Lake Region, Northwestern Ontario, Canada, Ernest John Thalhamer

Theses and Dissertations

The Grassy Portage Sill (GPS) is a ~2.7 Ga metagabbroic sill located in the Rainy Lake region of northwestern Ontario. The Rainy Lake region is located in the Superior Province between the metavolcanic Wabigoon subprovince to the north and the metasedimentary Quetico subprovince to the south. Two regional faults bound the region and intersect to the east, forming a wedge which defines the Rainy Lake zone. This area was regionally deformed due to oblique transpression, resulting from the Kenoran Orogeny (~2.7 Ga). The GPS is approximately 20 km long and 1-2 km wide, and has undergone heterogeneous strain along its …

Waddle - Always-Canonical Intermediate Representation, Eric Drew Fritz

Theses and Dissertations

Program transformations that are able to rely on the presence of canonical properties of the program undergoing optimization can be written to be more robust and efficient than an equivalent but generalized transformation that also handles non-canonical programs. If a canonical property is required but broken earlier in an earlier transformation, it must be rebuilt (often from scratch). This additional work can be a dominating factor in compilation time when many transformations are applied over large programs. This dissertation introduces a methodology for constructing program transformations so that the program remains in an always-canonical form as the program is mutated, …

Cost-Effective Load Scheduling For Hybrid Renewable Energy Systems, Avinash Shashikala Rajendra

Theses and Dissertations

Hybrid renewable energy systems offer great promise for the future. However, some lingering concerns regarding stability and cost efficiency still exist. If a private party installs the system and maintains full control, the party may itself alleviate some of these problems by wisely optimizing the benefits offered by the system. One of the ways to do so is to develop a schedule for their load such that the cost incurred is minimized; this is done by maximally utilizing the renewable sources of energy before using the backup options of more conventional energy sources. Creating such a schedule involves considering several …

3d Shape Descriptor-Based Facial Landmark Detection: A Machine Learning Approach, Reihaneh Rostami

Theses and Dissertations

Facial landmark detection on 3D human faces has had numerous applications in the literature

such as establishing point-to-point correspondence between 3D face models which is itself a

key step for a wide range of applications like 3D face detection and authentication, matching,

reconstruction, and retrieval, to name a few.

Two groups of approaches, namely knowledge-driven and data-driven approaches, have been

employed for facial landmarking in the literature. Knowledge-driven techniques are the

traditional approaches that have been widely used to locate landmarks on human faces. In

these approaches, a user with sucient knowledge and experience usually denes features to

be extracted …

Improving International Development Evaluation Through Geospatial Data And Analysis, Malte Lech, Juha Ilari Uitto, Sven Harten, Geeta Batra, Anupam Anand

International Journal of Geospatial and Environmental Research

Increasing availability of new types of data strengthens geospatial research in different scientific fields and opens up opportunities to better measure results and evaluate the impacts of development interventions. This article presents examples where geospatial approaches have been applied in evaluations and thus demonstrate the potential use in informing policy design through scientifically sound evidence as well as learning.

The authors illustrate innovative ways of employing geospatial data and analysis in impact evaluations of international development cooperation. These interventions are concerned with topics such as biodiversity conservation, land degradation, sustainable use of natural resources, and disaster risk management. Recent methodological …

Estimating And Correcting Interference Fringes In Infrared Spectra In Infrared Hyperspectral Imaging, Ghazal Azarfar, Ebrahim Aboualizadeh, Nicholas Walter,, Simona Ratti, Camilla Olivieri, Alessandra Alessandra, Michael Nasse, Achim Kohler, Mario Giordano, Carol Hirschmugl

Physics Faculty Articles

Short-term acclimation response of individual cells of Thalassiosira weissflogii was monitored by Synchrotron FTIR imaging over the span of 75 minutes. The cells, collected from batch cultures, were maintained in a constant flow of medium, at an irradiance of 120 μmol m−2 s−1 and at 20 °C. Multiple internal reflections due to the micro fluidic channel were modeled, and showed that fringes are additive sinusoids to the pure absorption of the other components of the system. Preprocessing of the hyperspectral cube (x, y, Abs(λ)) included removing spectral fringe using an EMSC approach. Principal component analysis of the time series of …

Using Self-Organizing Maps As A Forecasting Tool, Andrea Honor

Theses and Dissertations

Some extreme weather events, such as the early season heavy snow and cold weather outbreak of early November 2014, can be traced back to the influence of tropical or extratropical cyclones on the planetary scale flow. Such planetary scale reorganization also occurs in conjunction with serial extratropical cyclogenesis. Potential temperature on the dynamic tropopause (defined by the 2 PVU surface) allows for a dynamically compact characterization of the flow. NCEP Climate Forecast Systems Reanalysis data spanning 32 years are used to provide this measure, and Self-Organizing Maps (SOM) are then constructed to identify our atmospheric regimes. Key elements of this …

Using Drones To Generate New Data For Conservation Insights, Paul Lorah, Alice Ready, Emma Rinn

International Journal of Geospatial and Environmental Research

Human impact on the environment is driving a decline in biodiversity that heightens the need for informed management of conservation lands. Unmanned aerial vehicles (UAVs), also known as drones, are an increasingly cost-effective tool for generating high-quality data used to map landscape features, analyze land cover change and assess the effectiveness of conservation efforts. Traditional sources of remotely sensed data such as satellites and aircraft can be costly, inflexible and unable to detect fine-scale surface variation. This paper explores the advantages (and challenges) of analyzing data collected by drones to generate useful conservation management insights. We focus on three key …

Conservation Genomics Of Cascades Frogs (Rana Cascadae) At The Southern Edge Of Their Range, Bennett Hardy

Theses and Dissertations

Cascades frogs (Rana cascadae) in the southern Cascades Range of California have been declining over the last 30 years, primarily due to the fungal pathogen, Batrachochytrium dendrobatidis (Bd). In the Lassen Region of the southern Cascades, at least six of the eleven remaining localities face extirpation within 50 years. These small and isolated populations are prone to negative genetic effects including reduced diversity and increased inbreeding which could potentially exacerbate declines. I used a large dataset of SNP loci generated from high-throughput sequencing to characterize patterns of genetic structure and diversity in twelve R. cascadae populations in California to prioritize …

Spatial And Temporal Variation Of Phytoplankton Production In Lake Michigan, Katelyn Alexis Bockwoldt

Theses and Dissertations

Although many studies have documented decreases in phytoplankton production since the quagga mussel invasion, we currently have a limited understanding of the spatial variation and temporal dynamics of phytoplankton production in Lake Michigan. In this study, phytoplankton production and seston stoichiometry were measured bi-weekly near Milwaukee, three times at two northern basin sites, and along three nearshore-offshore transects from May to November 2017, as well as at 5-6 sites on three whole-lake surveys in 2016 and 2017. Estimates of growth rates were calculated from phytoplankton production and carbon measurements. In spring 2016 and 2017, growth estimates were similar across the …

Online Social Networks’ Investigations Of Individuals’ Healthy And Unhealthy Lifestyle Behaviors And Social Factors Influencing Them —Three Essays, Mahyar Sharif Vaghefi

Theses and Dissertations

More than half of U.S. adults suffer from one or more chronic diseases, which account for 86% of total U.S. healthcare costs. Major contributors to chronic diseases are unhealthy lifestyle behaviors, which include lack of physical activity, poor nutrition, tobacco use, and drinking too much alcohol. A reduction in the prevalence of health-risk behaviors could improve individuals’ longevity and quality of life and may halt the exponential growth of healthcare costs. Prior studies in the field have acknowledged that a comprehensive understanding of health behaviors requires the examination of individual’ behaviors in supra-dyadic social networks. In recent years, the growth …

Scanning Tunneling Microscopy Studies Of Superconducting Single Layer Iron Selenide On Strontium Titanate, Zhuozhi Ge

Theses and Dissertations

The search for high temperature superconductivity has been a prominent topic in the field of condensed matter physics ever since the discovery of this novel phenomenon more than 100 years ago. In addition to the search for new materials, interfacial superconductivity has shown great potential as demonstrated recently in monolayer FeSe grown on SrTiO3 (STO) (001) substrate, where superconducting transition temperature (Tc) has been enhanced by more than an order of magnitude compared to the bulk value. The uniqueness of this approach is the direct placement of the superconducting layer on a secondary substrate, which facilitates the independent control of …

The Geochemistry And Mineralogy Of Surface Hydrothermal Alteration At Nesjavellir, Sw Iceland, Chase Glenister

Theses and Dissertations

Abundant sulfates have been detected by the Mars Exploration Rover Spirit in the Columbia Hills of Mars, consistent with extensive alteration of basalt by hydrothermal processes. This study uses Iceland’s Nesjavellir geothermal system as an analogue for Columbia Hills hydrothermal alteration. This terrestrial site is home to a variety of acidic and near-neutral waters that are actively altering the Mars-like basalt of host volcano Mt. Hengill. Hydrothermal features heated by H2S gas and phase-segregated steam created oxidizing acid-sulfate conditions at the surface with pH values varying between 3.0 and 2.0 and near-boiling temperatures. Mobilization of cations (FeO, MgO, CaO, Na2O, …

Developing A Probabilistic Heavy-Rainfall Guidance Forecast Model For Great Lakes Cities, Cory Kevin Rothstein

Theses and Dissertations

A method for predicting the probability of exceeding specific warm-season (April-October) 0-24 hour precipitation thresholds is developed based upon daily maximums of meteorological parameters. North American Regional Reanalysis and Daily Unified Precipitation data from 2002-2017 were used to gather meteorological data for the Milwaukee and Chicago County Warning Areas. Individual artificial neural networks and multiple logistic regressions were conducted for daily rainfall thresholds above 0.5'', 1'', 1.5'' and 2'' to determine the probability of threshold exceedances for each County Warning Area. The most important parameters were 1000-500 hPa specific humidity, vertical velocities at various levels, high cloud cover, precipitable water …

Crystal Growth And Manipulation Of Intercalated Chalcogenides As Superconductors And Topological Insulators, Nathaniel Smith

Theses and Dissertations

Superconductors are unusual quantum materials which offer no resistance to electric current. The fascinating physics of this phenomenon is complemented by wide-ranging technical applications from power transmission to magnetic levitation. Commercially successful superconductors are found in powerful magnets in medical imaging, particle accelerators, and next-generation quantum computing. In my effort to uncover the mysteries and fundamental mechanisms of superconductivity, I use an array of techniques to synthesize and study single crystals of unconventional superconductors including the iron telluride and bismuth selenide family of superconductors. My study of atomic valence and crystal structure in iron telluride has uncovered previously unknown chemical …

Using Advanced Post-Processing Methods With The Hrrr-Tle To Improve The Prediction Of Cold Season Precipitation Type, Timothy Thielke

Theses and Dissertations

In this study we explore advanced statistical methods with the operational High-Resolution Rapid Refresh Model (HRRR) Time-Lagged Ensemble (TLE) to improve the prediction of cold season precipitation type. TLEs are a computationally efficient method to provide a slightly improved probabilistic forecast as the differences between model runs are an approximation of initial condition uncertainty. We apply evolutionary programming, weight-decay bias correction, and Bayesian Model Combination with fifteen HRRR forecast variables that potentially relate to precipitation type for station locations in the contiguous United States that are along and to the east of 100 W longitude to obtain probabilistic precipitation type …

Network Analysis Of Scientific Collaboration And Co-Authorship Of The Trifecta Of Malaria, Tuberculosis And Hiv/Aids In Benin., Gbedegnon Roseric Azondekon

Theses and Dissertations

Despite the international mobilization and increase in research funding, Malaria, Tuberculosis and HIV/AIDS are three infectious diseases that have claimed more lives in sub Saharan Africa than any other place in the World. Consortia, research network and research centers both in Africa and around the world team up in a multidisciplinary and transdisciplinary approach to boost efforts to curb these diseases. Despite the progress in research, very little is known about the dynamics of research collaboration in the fight of these Infectious Diseases in Africa resulting in a lack of information on the relationship between African research collaborators. This dissertation …