Physical Sciences and Mathematics Commons^™

Numerical Schemes For Integro-Differential Equations Related To Alpha-Stable Processes, Xiaofan Li

Mathematics Colloquium Series

The mean first exit time, escape probability and transitional probability densities are utilized to quantify dynamical behaviors of stochastic differential equations with non-Gaussian, α-stable type Lévy motions. Taking advantage of the Toeplitz matrix structure of the time-space discretization, a fast and accurate numerical algorithm is proposed to simulate the nonlocal Fokker-Planck equations on either a bounded or infinite domain. Under a specified condition, the scheme is shown to satisfy a discrete maximum principle and to be convergent. The numerical results for two prototypical stochastic systems, the Ornstein-Uhlenbeck system and the double-well system are shown.

Spectral Theorem Approach To The Characteristic Function Of Quantum Observables, Andreas Boukas

Journal of Stochastic Analysis

No abstract provided.

Robustness Analysis Of Classification Using Recurrent Neural Networks With Perturbed Sequential Input, Guangyi Liu, Arash Amini, Martin Takac, Nader Motee

Machine Learning Faculty Publications

For a given stable recurrent neural network (RNN) that is trained to perform a classification task using sequential inputs, we quantify explicit robustness bounds as a function of trainable weight matrices. The sequential inputs can be perturbed in various ways, e.g., streaming images can be deformed due to robot motion or imperfect camera lens. Using the notion of the Voronoi diagram and Lipschitz properties of stable RNNs, we provide a thorough analysis and characterize the maximum allowable perturbations while guaranteeing the full accuracy of the classification task. We illustrate and validate our theoretical results using a map dataset with clouds …

Canopy Spectral Reflectance Detects Oak Wilt At The Landscape Scale Using Phylogenetic Discrimination, Gerard Sapes, Cathleen Lapadat, Anna K. Schweiger, Jennifer Juzwik, Rebecca Montgomery, Hamed Gholizadeh, Philip A. Townsend, John A. Gamon, Jeannine Cavender-Bares

School of Natural Resources: Faculty Publications

The oak wilt disease caused by the invasive fungal pathogen Bretziella fagacearum is one of the greatest threats to oak-dominated forests across the Eastern United States. Accurate detection and monitoring over large areas are necessary for management activities to effectively mitigate and prevent the spread of oak wilt. Canopy spectral reflectance contains both phylogenetic and physiological information across the visible near-infrared (VNIR) and short-wave infrared (SWIR) ranges that can be used to identify diseased red oaks. We develop partial least square discriminant analysis (PLS-DA) models using airborne hyperspectral reflectance to detect diseased canopies and assess the importance of VNIR, SWIR, …

Search For Wγ Resonances In Proton-Proton Collisions At S=13 Tev Using Hadronic Decays Of Lorentz-Boosted W Bosons, The Cms Collaboration, A. Tumasyan, W. Adam, J. W. Andrejkovic, T. Bergauer, S. Chatterjee, Julie M. Hogan

Physics and Engineering Faculty Publications

A search for Wγ resonances in the mass range between 0.7 and 6.0 TeV is presented. The W boson is reconstructed via its hadronic decays, with the final-state products forming a single large-radius jet, owing to a high Lorentz boost of the W boson. The search is based on proton-proton collision data at s=13 TeV, corresponding to an integrated luminosity of 137 fb−1, collected with the CMS detector at the LHC in 2016–2018. The Wγ mass spectrum is parameterized with a smoothly falling background function and examined for the presence of resonance-like signals. No significant excess above the predicted background …

Effect Of Nitrogen Fertilization On Central Tendency And Spatial Heterogeneity Of Soil Moisture, Ph And Dissolved Organic Carbon And Nitrogen In Two Bioenergy Croplands, Xuehan Wang, Siyang Jian, Lahiru Gamage, Jianwei Li

Agricultural and Environmental Sciences Faculty Research

Background

Soil moisture, pH, dissolved organic carbon and nitrogen (DOC, DON) are important soil biogeochemical properties in switchgrass (SG) and gamagrass (GG) croplands. Yet their spatiotemporal patterns under nitrogen (N) fertilization have not been studied.

Aims

The objective of this study is to investigate the main and interactive effects of N fertilization and bioenergy crop type on central tendencies and spatial heterogeneity of soil moisture, pH, DOC and DON.

Methods

Based on a 3-year long fertilization experiment in Middle Tennessee, USA, 288 samples of top horizon soils (0–15 cm) under three fertilization treatments in SG and GG croplands were collected. …

The Phase Diagram Of A Non-Ideal Mixture’S P − V − X 2-Component Gas=Liquid Representation, Including Azeotropes, Carl W. David

Chemistry Education Materials

The liquid=vapor two phase p−v−x diagram is constructed for non-ideal solutions including azeotropes.

Measurement Of Structure Dependent Radiative K+ -> E,Sup>(+) Vy Gamma Decays Using Stopped Positive Kaons, H. Ito, A. Kobayashi, S. Bianchin, T. Cao, C. Djalali, D. H. Dongwi, T. Gautam, D. Gill, M. D. Hasinoff, K. Horie, Y. Igarashi, J. Imazato, N. Kalantarians, H. Kawai, S. Kimura, S. Kodama, M. Kohl, H. Lu, O. Mineev, Steffen Strauch, Et. Al.

Faculty Publications

The structure dependent radiative K + → e+νγ (K^SD+_e2γ) decay was investigated with stopped positive kaons. The e⁺ momentum spectra containing 574±30 K^SD+_e2γ events with a K + → μ+ν (K_μ2) background of 28 ± 19 events were measured with and without a photon in coincidence and analyzed with Monte Carlo simulations for acceptance and detector response to extract the ratio of the branching ratio of the K^SD+_e2γ decay and the K + → e+ν decay including the internal bremsstrahlung process (K_{e2(γ )}). …

Volitional Control Of Lower-Limb Prosthesis With Vision-Assisted Environmental Awareness, S M Shafiul Hasan

FIU Electronic Theses and Dissertations

Early and reliable prediction of user’s intention to change locomotion mode or speed is critical for a smooth and natural lower limb prosthesis. Meanwhile, incorporation of explicit environmental feedback can facilitate context aware intelligent prosthesis which allows seamless operation in a variety of gait demands. This dissertation introduces environmental awareness through computer vision and enables early and accurate prediction of intention to start, stop or change speeds while walking. Electromyography (EMG), Electroencephalography (EEG), Inertial Measurement Unit (IMU), and Ground Reaction Force (GRF) sensors were used to predict intention to start, stop or increase walking speed. Furthermore, it was investigated whether …

Pad Beyond The Classroom: Integrating Pad In The Scrum Workplace, Jade S. Weiss

USF Tampa Graduate Theses and Dissertations

Purpose: The “story” format used in Scrum ticket writing is confusing to developers and leadsto insufficient ticket content, which lends to miscommunication between team members and administrators, and disrupts workflow from the bottom up. A burgeoning methodology in Technical Writing, Purpose, Audience, Design (PAD) is an alternative ticket format that is easier to teach developers and improves the aforementioned conditions than the existing “story” format. The goal of this paper is to lay out why and how PAD can benefit developers on smaller Scrum teams who are tasked with writing their own tickets. This paper does not offer solutions for …

Spin-Orbit Gravitational Locking - An Effective Potential Approach, Christopher Clouse, Andrea Ferroglia, Miguel C. N. Fiolhais

Publications and Research

The objective of this paper is to study the tidally locked 3:2 spin–orbit resonance of Mercury around the Sun. In order to achieve this goal, the effective potential energy that determines the spinning motion of an ellipsoidal planet around its axis is considered. By studying the rotational potential energy of an ellipsoidal planet orbiting a spherical star on an elliptic orbit with fixed eccentricity and semi-major axis, it is shown that the system presents an infinite number of metastable equilibrium configurations. These states correspond to local minima of the rotational potential energy averaged over an orbit, where the ratio between …

Search For Strongly Interacting Massive Particles Generating Trackless Jets In Proton–Proton Collisions At √S = 13tev, A. Tumasyan

Department of Physics and Astronomy: Faculty Publications

A search for dark matter in the form of strongly interacting massive particles (SIMPs) using the CMS detector at the LHC is presented. The SIMPs would be produced in pairs that manifest themselves as pairs of jets without tracks. The energy fraction of jets carried by charged particles is used as a key discriminator to suppress efficiently the large multijet background, and the remaining background is estimated directly from data. The search is performed using proton–proton collision data corresponding to an integrated luminosity of 16.1 fb⁻¹, collected with the CMS detector in 2016. No significant excess of events …

Developing Reinforcement Learning Algorithms For Robots To Aim And Pour Solid Objects, Haoxuan Li

USF Tampa Graduate Theses and Dissertations

Pouring is one of the most commonly executed tasks in a variety of environments. Thereis less attention paid to pouring solid objects and avoiding spillage. Learning the dynamics for pouring solid objects can be a challenge because the collisions and static frictions between objects make their trajectories less predictable than liquid. Nonetheless, pouring solid objects is an important task in real life. In this work, we propose a solution to help robots aim and pour solid objects. The agents will learn how to interact with the environment and identify the optimal pouring trajectories, then manipulate the arm to aim at …

Lakshadweep High Propagation And Impacts On The Somali Current And Eddies During The Southwest Monsoon, Paul A. Ernst, Bulusu Subrahmanyam, Corinne B. Trott

Faculty Publications

Climatological eddies in the Arabian Sea (AS), including the Lakshadweep High (LH) and the Great Whirl (GW), play major roles in the regional fluxes of upper ocean properties. For the first time, we apply an eddy tracking algorithm to the LH using altimetric sea surface height observations from 1993 through 2019. We additionally analyze the LH's water mass composition throughout its life cycle using the 1/12° Global eddy resolving physical ocean and sea ice reanalysis (GLORYS12). We observe that the second annual downwelling coastal Kelvin wave's (CKW) arrival during the winter monsoon is primarily responsible for generating the LH. In …

Using Intrinsically-Typed Definitional Interpreters To Verify Compiler Optimizations In A Monadic Intermediate Language, Dani Barrack

Dissertations and Theses

Compiler optimizations are critical to the efficiency of modern functional programs. At the same time, optimizations that unintentionally change the semantics of programs can systematically introduce errors into programs that pass through them. The question of how to best verify that optimizations and other program transformations preserve semantics is an important one, given the potential for error introduction. Dependent types allow us to prove that properties about our programs are correct, as well as to design data types and interpreters in such a way that they are correct-by-construction. In this thesis, we explore the use of dependent types and intrinsically-typed …

Understanding Common Perceptions Of The Drylands, C. Bedelian, D. Pertaub, F. Ngarachu, C. Hesse, S. Krätli, J. Obando, C. Shisanya, J. Maraigua

IGC Proceedings (1993-2023)

Drylands occupy over 40% of the earth’s surface and are home to more than 2 billion people. Drylands are key to the food and nutritional security of the planet and vital to the economies and livelihoods of dryland inhabitants. Yet, drylands are commonly perceived as unproductive, economically inefficient and marginal lands where small-scale farmers and pastoralists practice environmentally degrading activities. Driven by inadequate understanding and misconceptions of the drylands, policy-makers devise inappropriate policies and interventions. The BRECcIA project developed an online Drylands Perceptions Survey to understand the perceptions of researchers, practitioners and policy makers working in the drylands of Kenya, …

Relationships Between Biodiversity And Production In Grasslands At Local And Regional Scales, A. Hector, M. Loreau

IGC Proceedings (1993-2023)

Key points

1. Experimental manipulations of plant species diversity in unfertilised prairies and meadows has revealed that increasing diversity often leads to increased productivity (range of observed relationships varies from flat to log-linearly positive); driven by a combination of facilitation, niche-partitioning and sampling/selection effects.

2. The longer-term effects of diversity on ecosystem stability are not as clear and in need of further work.

3. Recent applied work, and a new review of the grassland literature, both show the potential for biodiversity to increase productivity under realistic field conditions.

4. The longer-term feedback of grazers on biodiversity gradients is unknown, and …

Methane And Nitrous Oxide Emissions From Grazed Grasslands, Harry Clark, C. Pinares-Patiño, C. De Klein

IGC Proceedings (1993-2023)

Key points

1. Emissions of methane (CH₄) and nitrous oxide (N₂O) from grasslands make a substantial contribution to total agricultural emissions of these two gases.

2. At present practical mitigation options that relate to grazing ruminants and grazed pastures are limited.

3. Research into agricultural greenhouse gas emissions is of low priority in most developed countries.

4. Direct manipulation of the rumen ecosystem provides the best opportunity for large reductions in CH₄ in the long term.

5. Reducing the amount of nitrogen (N) excreted by grazing animals is a priority in N₂O research, …

Phenotypic Evaluation Of Energycane Varieties For Bioenergy, Wyatt Eason, D. M. Hollowell, Anna Hale, Jesse Ira Morrison, Brian Baldwin

IGC Proceedings (1993-2023)

The need for renewable and carbon-neutral energy is growing as fossil fuel supplies decrease and concerns of climate change increase. C₄ grasses are among the most efficient carbon accumulators. Sugarcane (Saccharum officinarum) is a renewable bioenergy crop with low inputs and high yields, but it is limited to tropical and sub-tropical climates. A close relative, Saccharum spontaneum, readily hybridizes with S. officinarum. S. spontaneum lends cold tolerance and higher yields to the hybrid progeny, called energycane. The Sugarcane Breeding Unit (USDA, Houma, Louisiana, USA) selected twenty-six genotypes for testing at Mississippi State University to determine production …

Clustering For The Neophyte: An R Shiny App For Self-Organizing Maps, Olcay Akman, Zury Betzab-Marroquin, Christopher Hay-Jahans, Joshua Walsh, Trenton Wesley

Spora: A Journal of Biomathematics

This article provides an outline of clustering, key stages in creating self-organizing maps for purposes of clustering, instructions on how to use a free online R Shiny app that constructs self-organizing maps for data provided by users, and interpretations of the graphics produced.

Seasonally And Diurnally Varying Cold Front Effects Along The Minnesotan North Shore Of Lake Superior, Matthew S. Van Den Broeke

Department of Earth and Atmospheric Sciences: Faculty Publications

Cold fronts are typically associated with cooling, drying and a strengthening wind that shifts to have a northerly component. Cold front effects at a particular point, however, are dependent upon pre-existing air mass characteristics. Here, we examine 634 passages of synoptic-scale cold fronts in northeastern Minnesota from 2010 to 2018. While these fronts are associated with the expected effects in some areas, they are often associated with warming and enhanced drying in the region directly influenced by an air mass from Lake Superior (coastal sites). Coastal sites experience warming during more than half of cold frontal passages, in contrast to …

Use Of Machine Learning Approaches And Statistical Techniques To Adjust For Nonadherence In Randomized Clinical Trials., Andrew G Chapple

School of Public Health Faculty Publications

No abstract provided.

Considering Sustainability From The Perspective Of Accountability: Rethinking Consumerism And The Environment, Tabassum Fahim Ruby, Madeline Mulcahey, Christine Recchi

Sustainability Research & Practice Seminar Presentations

Professor Tabassum Ruby, Women’s and Gender Studies, with Madeline Mulcahey and Christine Recchi - Considering Sustainability from the Perspective of Accountability: Rethinking Consumerism and the Environment

Establishing Trust In Vehicle-To-Vehicle Coordination: A Sensor Fusion Approach, Jakob Veselsky, Jack West, Isaac Ahlgren, George K. Thiruvathukal, Neil Klingensmith, Abhinav Goel, Wenxin Jiang, James C. Davis, Kyuin Lee, Younghyun Kim

Computer Science: Faculty Publications and Other Works

As we add more autonomous and semi-autonomous vehicles (AVs) to our roads, their effects on passenger and pedestrian safety are becoming more important. Despite extensive testing, AVs do not always identify roadway hazards. Failures in object recognition components have already led to several fatal collisions, e.g. as a result of faults in sensors, software, or vantage point. Although a particular AV may fail, there is an untapped pool of information held by other AVs in the vicinity that could be used to identify roadway hazards before they present a safety threat.

Considerations For Radio Frequency Fingerprinting Across Multiple Frequency Channels, Jose A. Gutierrez Del Arroyo, Brett J. Borghetti, Michael A. Temple

Faculty Publications

Radio Frequency Fingerprinting (RFF) is often proposed as an authentication mechanism for wireless device security, but application of existing techniques in multi-channel scenarios is limited because prior models were created and evaluated using bursts from a single frequency channel without considering the effects of multi-channel operation. Our research evaluated the multi-channel performance of four single-channel models with increasing complexity, to include a simple discriminant analysis model and three neural networks. Performance characterization using the multi-class Matthews Correlation Coefficient (MCC) revealed that using frequency channels other than those used to train the models can lead to a deterioration in performance from …

Quantitative Assessment Of The Trophic Ecology Of The Oceanic Ctenophore, Bolinopsis Infundibulum, In Monterey Bay, California, Victoria C. Scriven

USF Tampa Graduate Theses and Dissertations

Bolinopsis infundibulum is a wide-ranging, ubiquitous ctenophore whose fragile nature makes the collection of specimens and quantification of key predator-prey activities in controlled laboratory experiments, challenging. Thus, in situ methods often represent the best means for data collection. However, while present in surface waters, these animals can also be abundant at depths well beyond those attainable by divers. As a result, very little empirical data exist over the depth range of their natural habitats which limits our ability to assess key predator-prey interactions needed to assess their ecological role in midwater food webs. Working in Monterey Bay, California, remotely operated …

Accuracy Assessment, Comparative Performance, And Enhancement Of Public Domain Digital Elevation Models (Aster 30 M, Srtm 30 M, Cartosat 30 M, Srtm 90 M, Merit 90 M, And Tandem-X 90 M) Using Dgps, Kumari Preety, Anup K. Prasad, Atul K. Varma, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Publicly available Digital Elevation Models (DEM) derived from various space-based platforms (Satellite/Space Shuttle Endeavour) have had a tremendous impact on the quantification of landscape characteristics, and the related processes and products. The accuracy of elevation data from six major public domain satellite-derived Digital Elevation Models (a 30 m grid size—ASTER GDEM version 3 (Ast30), SRTM version 3 (Srt30), CartoDEM version V3R1 (Crt30)—and 90 m grid size—SRTM version 4.1 (Srt90), MERIT (MRT90), and TanDEM-X (TDX90)), as well as the improvement in accuracy achieved by applying a correction (linear fit) using Differential Global Positioning System (DGPS) estimates at Ground Control Points (GCPs) …

Determinants Of Covid-19 Vaccinations Among A State-Wide Year-Long Surveillance Initiative In A Conservative Southern State, Lídia Gual-Gonzalez, Maggie S.J. Mccarter, Kyndall Dye-Braumuller, Stella Self, Connor H. Ross, Chloe Rodriguez-Ramos, Virginie G. Daguise, Melissa Nolan Ph.D., Mph

Faculty Publications

By the end of 2021, the COVID-19 pandemic resulted in over 54 million cases and more than 800,000 deaths in the United States, and over 350 million cases and more than 5 million deaths worldwide. The uniqueness and gravity of this pandemic have been reflected in the public health guidelines poorly received by a growing subset of the United States population. These poorly received guidelines, including vaccine receipt, are a highly complex psychosocial issue, and have impacted the successful prevention of disease spread. Given the intricate nature of this important barrier, any single statistical analysis methodologically fails to address all …

Oxygen Ion Escape At Venus Associated With Three-Dimensional Kelvin-Helmholtz Instability, Tong Dang, Xuanye Ma, Jiuhou Le, Binzheng Zhang, Tielong Zhang, Zhonghua Yao, John Lyon, Sudong Xiao, Maodong Yan, Oliver Brambles, Kareem Sorathia

Publications

How oxygens escape from Venus has long been a fundamental but controversial topic in the planetary research. Among various key mechanisms, the Kelvin-Helmholtz instability (KHI) has been suggested to play an important role in the oxygen ion escape from Venus. Limited by either scarce in-situ observations or simplified theoretical estimations, the mystery of oxygen ion escape process associated with KHI is still unsettled. Here we present the first three-dimensional configuration of KHI at Venus with a global multifluid magnetohydrodynamics model, showing a significantly fine structure and evolution of the KHI. KHI mainly occurred at the low latitude boundary layer if …

Fast-Decaying Plant Litter Enhances Soil Carbon In Temperate Forests But Not Through Microbial Physiological Traits, Matthew E. Craig, Kevin M. Geyer, Katilyn V. Beidler, Edward R. Brzostek, Serita D. Frey, A. Stuart Grandy, Chao Liang, Richard P. Phillips

Faculty Publications

Conceptual and empirical advances in soil biogeochemistry have challenged long-held assumptions about the role of soil micro-organisms in soil organic carbon (SOC) dynamics; yet, rigorous tests of emerging concepts remain sparse. Recent hypotheses suggest that microbial necromass production links plant inputs to SOC accumulation, with high-quality (i.e., rapidly decomposing) plant litter promoting microbial carbon use efficiency, growth, and turnover leading to more mineral stabilization of necromass. We test this hypothesis experimentally and with observations across six eastern US forests, using stable isotopes to measure microbial traits and SOC dynamics. Here we show, in both studies, that microbial growth, efficiency, and …