Physical Sciences and Mathematics Commons^™

A Comparison Of Five Statistical Methods For Predicting Stream Temperature Across Stream Networks, Maike F. Holthuijzen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The health of freshwater aquatic systems, particularly stream networks, is mainly influenced by water temperature, which controls biological processes and influences species distributions and aquatic biodiversity. Thermal regimes of rivers are likely to change in the future, due to climate change and other anthropogenic impacts, and our ability to predict stream temperatures will be critical in understanding distribution shifts of aquatic biota. Spatial statistical network models take into account spatial relationships but have drawbacks, including high computation times and data pre-processing requirements. Machine learning techniques and generalized additive models (GAM) are promising alternatives to the SSN model. Two machine learning …

29-Day Analysis Of Scale Heights And The Inference Of The Topside Ionosphere Over Millstone Hill During The 2002 Incoherent Scatter Radar Campaign, Jennifer L. Meehan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study aims to characterize the topside ionospheric density and temperature profiles using readily available Global Positioning System (GPS) total electron content (TEC) and ionosonde bottomside profile of electron density. The aim of this study is to find a technique that can be applied globally rather than specific locations where a wealth of data exists. Knowledge of the distribution of electron density and its altitude dependence, known as scale height, is important for ionospheric empirical modeling and ionospheric studies, and for practical applications, such as time delay correction of radiowave propagation through the ionosphere.

Over the years, researchers have gathered …

Optimal Warranty Period For Free-Replacement Policy Of Agm Batteries, Jennifer Paola Garantiva Poveda

Theses and Dissertations

The objective of this study is to analyze the suitability of the age-based warranty model and a millage based warranty model for absorbent glass mat batteries (AGM) for the automobile industry. The battery life expectancy can be assessed and described by a combination of different terms such as: state of health (SOH), deep of discharge (DOD), state of energy (SOE) and state of charge (SOC). However, using actual data from the field, the implementation of reliability engineering and statistical modeling we aim to calculate optimal limits for warranty policies that minimize warranty costs. The outcomes of this research will enable …

Investigation Of Catalytic Oxidation And Coupling Reactions On Gold, Palladium, And Gold-Palladium Alloys, Theodore Douglas Thuening

Theses and Dissertations

Polyvinyl acetate is a common adhesive and additive to emulsion-based paints produced in the millions of tons per year through the palladium catalyzed coupling of ethylene and acetic acid. Understanding the reaction mechanism and kinetics is integral to designing a more efficient catalyst through an increase in activity, selectivity, or both. It has been shown that selectivity for the vinyl acetate monomer (VAM) reaction increases to ~94% upon alloying palladium with gold compared to palladium alone (~80% selective).

The characterization of the VAM formation reaction on Pd(111) and Au/Pd(111) single crystal alloys has been extensively studied, but it has been …

Localization Of Large Scale Structures, Ryan James Jensen

Doctoral Dissertations

We begin by giving the definition of coarse structures by John Roe, but quickly move to the equivalent concept of large scale geometry given by Jerzy Dydak. Next we present some basic but often used concepts and results in large scale geometry. We then state and prove the equivalence of various definitions of asymptotic dimension for arbitrary large scale spaces. Some of these are generalizations of asymptotic dimension for metric spaces, and many of the proofs are new. Particularly useful in proving the equivalences of the various definitions is the notion of partitions of unity, originally set forth by Jerzy …

Detection Of A Substantial Molecular Gas Reservoir In A Brightest Cluster Galaxy At Z = 1.7, Tracy M.A. Webb, James Lowenthal, Min Yun, Allison G. Nobel, Adam Muzzin, Gillian Wilson, H.K.C. Yee, Ryan Cybulski, D. H. Hughes

Astronomy: Faculty Publications

We report the detection of CO(2–1) emission coincident with the brightest cluster galaxy (BCG) of the high- redshift galaxy cluster SpARCS1049+56, with the Redshift Search Receiver (RSR) on the Large Millimeter Telescope (LMT). We confirm a spectroscopic redshift for the gas of z = 1.7091 ± 0.0004, which is consistent with the systemic redshift of the cluster galaxies of z = 1.709. The line is well fit by a single-component Gaussian with an RSR-resolution-corrected FWHM of 569 ± 63kms−1. We see no evidence for multiple velocity components in the gas, as might be expected from the multiple image components seen …

Correlation Of Trichome Density And Length And Polyphenol Fluorescence With Susceptibility Of Five Cucurbits To Didymella Bryoniae, Gabriel Rennberger, A. P. Keinath, M. Hess

Publications

The fungal pathogen Didymella bryoniae causes gummy stem blight and black rot on a broad spectrum of cucurbits. However the substantial differences in susceptibility among Cucurbitaceae are not well studied. Susceptibility was characterized with muskmelon (Cucumis melo), watermelon (Citrullus lanatus), cucumber (Cucumis sativus), pumpkin (Cucurbita pepo), and zucchini (C. pepo). Lesion diameters on leaf disks inoculated with agar plugs were measured 7 days after inoculation, and the necrotized areas of leaf disks inoculated with conidial suspensions were measured 48 h after inoculation (hai). For each species, the number of trichomes …

Variations In Biocorona Formation Related To Defects In The Structure Of Single Walled Carbon Nanotubes And The Hyperlipidemic Disease State, Achyut J. Raghavendra, Kristofer Fritz, Sherleen Fu, Jared M. Brown, Ramakrishna Podila, Jonathan H. Shannahan

Publications

Ball-milling utilizes mechanical stress to modify properties of carbon nanotubes (CNTs) including size, capping, and functionalization. Ball-milling, however, may introduce structural defects resulting in altered CNT-biomolecule interactions. Nanomaterial-biomolecule interactions result in the formation of the biocorona (BC), which alters nanomaterial properties, function, and biological responses. The formation of the BC is governed by the nanomaterial physicochemical properties and the physiological environment. Underlying disease states such as cardiovascular disease can alter the biological milieu possibly leading to unique BC identities. In this ex vivo study, we evaluated variations in the formation of the BC on single-walled CNTs (SWCNTs) due to physicochemical …

Detection Of Comparability Subgraphs From Large Networks, Muthunagai Balakrishnamoorthy

Student Work

Real world large scale networks can be represented as graphs. This approach plays a key role in analysis in the domains of social networks [1] and bioinformatics [2], among others. Analyzing these networks is computationally complex and expensive, especially in terms of memory and time complexity. A popular technique subverting time and computation expense for analyzing networks is extracting substructures, which preserves more important information and less noise [12]. In this work, we use special a special substructure called comparability, which preserves transitive orientation. Our motive is to extract a maximal comparability subgraph since no algorithm exists. Our algorithm is …

Tool Support For Capturing The Essence Of A Concern In Source Code, Chuntao Fu

Student Work

Software evolves constantly to adapt to changing user needs. As it evolves, it becomes progressively harder to understand due to accumulation of code changes, increasing code size, and the introduction of complex code dependencies. As a result, it becomes harder to maintain, exposing the software to potential bugs and degradation of code quality. High maintenance costs and diminished opportunities for software reusability and portability lead to reduced return on investment, increasing the likelihood of the software product being discarded or replaced. Nevertheless, we believe that there is value in legacy software due to the amount of intellectual efforts that have …

Integration Of Multimodal Sensor Data For Targeted Assessment And Intervention, Shawn N. Gieser

Computer Science and Engineering Dissertations

Physical and Occupational Therapy have been used for many years to help people who have suffered an injury of some kind. This injury could be caused by a physical injury, such as falling or breaking a bone, or a brain injury, such as a stroke. Traditional interventions involve having a therapist watch a patient perform any prescribed interventions to see if they are done correctly and to assess progress, or to have a patient perform exercises at home unsupervised. Patients, once discharged, do not always adhere to the prescribed intervention. They begin to not keep scheduled appointments and not complete …

Magnesium Isotope Investigation Of Stromatolitic Knobs In Storr’S Lake, San Salvador, Bahamas: Implications For Organomineralization And Laminae Formation, Zijian Li

Earth & Environmental Sciences Theses

Storr’s Lake, a hypersaline lake located on San Salvador Island, Bahamas, contains modern, fine-grained stromatolites. This study focused on two morphological types of stromatolitic mounds in Storr’s Lake (pinnacle mound and plateau-mushroom) and systematically investigated their mineralogy, elemental abundance, carbon, oxygen and magnesium (Mg) isotopic signature to gain insights into the organomineralization process and laminae formation of stromatolites. In addition, the hydrochemistry of Storr’s Lake was characterized by in situ measurement of water parameters, elemental analysis, and Mg isotope investigation. Cations and anions analysis indicates the lake is spatially homogenous and shows little seasonal variation. Mg isotope analysis of the …

Enrichment Of Volcanogenic Trace Elements In A Continuous Subsurface Eagle Ford Core In South Texas And The Origin Of The Oceanic Anoxic Event Ii At The Cenomanian-Turonian (C/T) Boundary, Daniel Valencia

Earth & Environmental Sciences Theses

The Upper Cretaceous Eagle Ford Shale of South Texas is a dark grey to black, sporadically laminated, organic rich carbonaceous mud rock located in the subsurface (~13,000), of the hydrocarbon producing shale-oil formation. This black shale formation was deposited contemporaneously worldwide across the Cenomanian-Turonian (C/T) boundary and records the Oceanic Anoxic Event (OAE-II). Geochronological and geochemical analysis of a ~300ft long continuous South Texas Eagle Ford Shale core was conducted to further constrain the sub-surface nature of the formation. Major, minor and trace element concentrations were analyzed by ED-XRF to characterize the local geochemical heterogeneity in the formation. Total Organic …

Exploring Flexible Configurations Of A Custom Multipath Lc –Ms For Small Molecules And Protein Analysis, Dananjaya Kalu Appulage

Chemistry & Biochemistry Dissertations

There are diseases where both small molecules and proteins are found as disease indicators. In the usual analysis of small molecules, proteins are precipitated out during the sample preparation. In the small molecule quantitation, triple quadrupole mass spectrometers (QqQ- MS) are commonly used even in the clinical lab settings. Even though QqQ is giving only unit resolution, it is highly sensitive and specific specially when it is used in the multiple reaction monitoring (MRM) mode. In the liquid chromatography method development, automation of column and mobile phase screening could save significant amount of operators’ time. The use of Shimadzu Nexera …

F₄₂₀ Cofactor Dependent Enzymes : Kinetic, Mechanistic And Structural Characterization Of F₄₂₀-Dependent Glucose-6-Phosphate Dehydrogenase (Fgd) From Mycobacterium Tuberculosis, Mercy A. Oyugi

Chemistry & Biochemistry Dissertations

F₄₂₀-dependent glucose-6-phosphate dehydrogenase (FGD) from Mycobacterium tuberculosis (Mtb) is one of a few enzymes that utilize the unique F₄₂₀ cofactor for catalysis. FGD catalyzes the first committed step of the pentose-phosphate pathway, where it uses the oxidized F₄₂₀ cofactor to convert glucose-6-phosphate (G6P) to 6-phosphogluconolactone. Mtb is the bacteria that causes Tuberculosis (TB), which is currently the world’s deadliest bacterial disease. The pentose-phosphate pathway is important for survival of Mtb, since it provides precursors for nucleic acid synthesis and yields reducing equivalents that are essential for other metabolic pathways. The fact that FGD catalyzes the committed step of the pentose-phosphate …

Development Of Ultrahigh Performance Chiral Phases For Separations Approaching The Speed Of Sensors, Darshan C. Patel

Chemistry & Biochemistry Dissertations

Chromatography using chiral stationary phases is the most effective and popular technique for qualitative and quantitative analysis of enantiomers in the pharmaceutical, agricultural, and food industry, among many others. Given the prevalence of chirality in nature, creation of new technologies for improving the speed and performance of chiral separations can provide immediate and significant benefits. This dissertation focuses on development of ultrahigh performance chiral phases which can provide separations at speeds that approach the speed of typical sensors and thereby enable chromatography as a real-time analysis tool. A variety of chiral selectors namely macrocyclic glycopeptides (teicoplanin, teicoplanin aglycone, vancomycin), cyclic …

Toxicity Study Of Cace₂S₄, Wafa Tonny

Chemistry & Biochemistry Theses

In recent years, rare earth sulfides have received attention for their interesting thermoelectric and optical properties.1 They exhibit a fairly wide range of colors, which makes them promising candidates as pigments.2 The demand for red colored pigments in industrial application is high but the current ones in use are not environmentally friendly. This has garnered attention towards the rare-earth sulfides. Among the rare-earth sulfide compounds, Ce₂S₃ is a highperformance pigment of red color. It is particularly interesting as doping with alkaline earth metal stabilizes the structure of Ce₂S₃ at low temperature and plays a role in tuning its color from …

Enrichment And Identification Of Disulfide Bonded Peptides By Tandem Mass Spectrometry, Pooja Rajeshbhai Ramanuj

Chemistry & Biochemistry Theses

Proteins are Comprised of different amino acids which can undergo various modifications known as post-translational modifications (PTMs). Amino acid’s side chains are the most common sites for the PTMs. Cysteine side chain can undergo several PTMs and one very common one is disulfide bond formation. Disulfide bond aids in maintaining protein tertiary structures, its identification is an inevitable aspect in studying protein functions. Furthermore, disulfide bonds are potential targets to develop new protein therapeutics for life-threatening diseases such as cancer. Literature surveys revealed several methods to identify disulfide bonds, which require either high quality sample or are highly laborious. Moreover, …

Angular Distribution Of Single-Photon Superradiance In A Dilute And Cold Atomic Ensemble, A. S. Kuraptsev, I. M. Sokolov, M. D. Havey

Physics Faculty Publications

On the basis of a quantum microscopic approach we study the dynamics of the afterglow of a dilute Gaussian atomic ensemble excited by pulsed radiation. Taking into account the vector nature of the electromagnetic field we analyze in detail the angular and polarization distribution of single-photon superradiance of such an ensemble. The dependence of the angular distribution of superradiance on the length of the pulse and its carrier frequency as well as on the size and the shape of the atomic clouds is studied. We show that there is substantial dependence of the superradiant emission on the polarization and the …

Habitability Of Stellar Binary Systems, Zhaopeng Wang

Physics Dissertations

A comprehensive approach is provided to the study of habitable zones (HZs) for both S-type and P-type cases of stellar binary systems for both circular and elliptical orbits of the binary components, based on habitability limits for the Sun from previous work. Habitable regions are determined through the consideration of a joint constraint, including the planetary orbital stability and the extent of the radiative habitable zones (RHZs). The HZs are classified based on solar system habitability limits, which also consider different climate models. In this work, the new climate model published by Kopparapu in 2014 is used for RHZ calculation. …

Methylene Blue Degradation With Sodium Bismuth Oxide Nanoparticles, Suzanne Shuda

Physics Theses

The effectiveness of Sodium Bismuth Oxide nanoparticles as a photocatalyst was tested by applying it to the degradation of methylene blue. The nanoparticles had increased effectiveness with increased concentration and reaction time. However, when the particles were microwaved, there was not a significant change in the effectiveness of the nanoparticles. Therefore, these nanoparticles are not a good candidate for microwave induced photodynamic therapy, but they could be used on their own for other applications.

Chasing Boundaries And Cascade Effects In A Coupled Barrier-Marsh-Lagoon System, Jorge Lorenzo Trueba, Giulio Mariotti

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The long-term dynamic evolution of an idealized barrier-marsh-lagoon system experiencing sea-level rise is studied by coupling two existing numerical models. The barrier model accounts for the interaction between shoreface dynamics and overwash flux, which allows the occurrence of barrier drowning. The marsh-lagoon model includes both a backbarrier marsh and an interior marsh, and accounts for the modification of the wave regime associated with changes in lagoon width and depth. Overwash, the key process that connects the barrier shoreface with the marsh-lagoon ecosystems, is formulated to account for the role of the backbarrier marsh. Model results show that a number of …

Valuing Visitor Services And Access To Protected Areas: The Case Of Nyungwe National Park In Rwanda, Pankaj Lal, Bernabas Wolde, Michel Masozera, Pralhad Burli, Janaki Alavalapati, Aditi Ranjan, Jensen Montambault, Onil Banerjee, Thomas Ochuodho, Rodrigue Mugabo

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Policymakers and recreation site managers use changes in fee structure, either introducing park entrance fees or increasing existing ones, to generate revenues, improve services, and reduce damages associated with over-use. Increase in park usage fee, however, can make the park inaccessible to certain segments of tourists. Understanding park users' response to changes in fees and its implication on park use equity is, thus, important to achieving a park's full potential in a socially and environmentally responsible way. This information is crucial especially for developing countries, where the issue has received relatively less attention and national park systems are chronically underfunded. …

Enantioselective Γ- And Δ -Borylation Of Unsaturated Carbonyl Derivatives: Synthesis, Mechanistic Insights, And Applications., Gia L. Hoang

Department of Chemistry: Dissertations, Theses, and Student Research

Chiral boronic esters are valuable synthetic intermediates widely used in a variety of stereospecific transformations. Transition metal-catalyzed asymmetric hydroboration (CAHB) of alkenes is among the most popular methods for their preparation. Enantioselective hydroboration of activated alkenes (i.e., vinyl arene derivatives or conjugated carbonyl compounds) have been extensively studied by many research groups. We, on the other hand, are interested in enantioselective hydroboration of unactivated alkenes utilizing coordinating functional groups (e.g., carbonyl derivatives) to give functionalized, chiral boronic esters. While conjugate addition and C–H activation methodologies provide efficient alternatives to CAHB for enantioselective beta-borylation of carbonyl compounds, direct gamma- and delta-borylations …

Optimal Security Reductions For Unique Signatures: Bypassing Impossibilities With A Counterexample, Fuchun Fuo, Rongmao Chen, Willy Susilo, Jianchang Lai, Guomin Yang, Yi Mu

Research Collection School Of Computing and Information Systems

Optimal security reductions for unique signatures (Coron, Eurocrypt 2002) and their generalization, i.e., efficiently re-randomizable signatures (Hofheinz et al. PKC 2012 & Bader et al. Eurocrypt 2016) have been well studied in the literature. Particularly, it has been shown that under a non-interactive hard assumption, any security reduction (with or without random oracles) for a unique signature scheme or an efficiently re-randomizable signature scheme must loose a factor of at least qsqs in the security model of existential unforgeability against chosen-message attacks (EU-CMA), where qsqs denotes the number of signature queries. Note that the number qsqs can be as large …

Don’T Bury Your Head In Warnings: A Game-Theoretic Approach For Intelligent Allocation Of Cyber-Security Alerts, Aaron Schlenker, Haifeng Xu, Mina Guirguis, Christopher Kiekintveld, Arunesh Sinha, Milind Tambe, Solomon Sonya, Darryl Balderas, Noah Dunstatter

Research Collection School Of Computing and Information Systems

In recent years, there have been a number of successful cyber attacks on enterprise networks by malicious actors which have caused severe damage. These networks have Intrusion Detection and Prevention Systems in place to protect them, but they are notorious for producing a high volume of alerts. These alerts must be investigated by cyber analysts to determine whether they are an attack or benign. Unfortunately, there are magnitude more alerts generated than there are cyber analysts to investigate them. This trend is expected to continue into the future creating a need for tools which find optimal assignments of the incoming …

Measuring Fine-Grained Metro Interchange Time Via Smartphones, Weixi Gu, Kai Zhang, Zimu Zhou, Ming Jin, Yuxun Zhou, Xi Liu, Costas J. Spanos, Zuo-Jun (Max) Shen, Wei-Hua Lin, Lin Zhang

Research Collection School Of Computing and Information Systems

High variability interchange times often significantly affect the reliability of metro travels. Fine-grained measurements of interchange times during metro transfers can provide valuable insights on the crowdedness of stations, usage of station facilities and efficiency of metro lines. Measuring interchange times in metro systems is challenging since agentoperated systems like automatic fare collection systems only provide coarse-grained trip information and popular localization services like GPS are often inaccessible underground. In this paper, we propose a smartphone-based interchange time measuring method from the passengers’ perspective. It leverages low-power sensors embedded in modern smartphones to record ambient contextual features, and utilizes a …

Pivot-Based Metric Indexing, Lu Chen, Yunjun Gao, Baihua Zheng, Christian S. Jensen, Hanyu Yang, Keyu Yang

Research Collection School Of Computing and Information Systems

The general notion of a metric space encompasses a diverse range of data types and accompanying similarity measures. Hence, metric search plays an important role in a wide range of settings, including multimedia retrieval, data mining, and data integration. With the aim of accelerating metric search, a collection of pivot-based indexing techniques for metric data has been proposed, which reduces the number of potentially expensive similarity comparisons by exploiting the triangle inequality for pruning and validation. However, no comprehensive empirical study of those techniques exists. Existing studies each offers only a narrower coverage, and they use different pivot selection strategies …

Transaction Cost Optimization For Online Portfolio Selection, Bin Li, Jialei Wang, Dingjiang Huang, Steven C. H. Hoi

Research Collection School Of Computing and Information Systems

To improve existing online portfolio selection strategies in the case of non-zero transaction costs, we propose a novel framework named Transaction Cost Optimization (TCO). The TCO framework incorporates the L1 norm of the difference between two consecutive allocations together with the principles of maximizing expected log return. We further solve the formulation via convex optimization, and obtain two closed-form portfolio update formulas, which follow the same principle as Proportional Portfolio Rebalancing (PPR) in industry. We empirically evaluate the proposed framework using four commonly used data-sets. Although these data-sets do not consider delisted firms and are thus subject to survival bias, …

Geometric Approaches For Top-K Queries [Tutorial], Kyriakos Mouratidis

Research Collection School Of Computing and Information Systems

Top-k processing is a well-studied problem with numerous applications that is becoming increasingly relevant with the growing availability of recommendation systems and decision-making software. The objective of this tutorial is twofold. First, we will delve into the geometric aspects of top-k processing. Second, we will cover complementary features to top-k queries, with strong practical relevance and important applications, that have a computational geometric nature. The tutorial will close with insights in the effect of dimensionality on the meaningfulness of top-k queries, and interesting similarities to nearest neighbor search.