Physical Sciences and Mathematics Commons^™

Embedding The Su(3) Sector Of So(8) Supergravity In D = 11, Gabriel Larios, Praxitelis Ntokos, Oscar J. Varela

All Physics Faculty Publications

The SU(3)-invariant sector of maximal supergravity in four dimensions with an SO(8) gauging is uplifted to D = 11 supergravity. In order to do this, the SU(3)-neutral sector of the tensor and duality hierarchies of the D = 4 �� = 8 supergravity is first worked out. The consistent D = 11 embedding of the full, dynamical SU(3) sector is then expressed at the level of the D = 11 metric and three-form gauge field in terms of these D = 4 tensors. The redundancies introduced by this approach are eliminated at the level of the D = 11 four-form …

Fewer Wetlands More Connectivity: Implications Of Land Use-Land Cover Change In An Agricultural Landscape, Stephanie Lawlor

USF Tampa Graduate Theses and Dissertations

St. Lucie County (SLC) is a 1,782 km2 area in east-central Florida that drains to the Nationally Significant Indian River Lagoon (IRL). It is low lying and nearly level, with widespread non-floodplain wetlands (NFWs) and few natural channels. NFWs comprise the vast majority of SLC wetlands, both in terms of numbers and area. Since the early 20th century, SLC has undergone extensive land use-land cover (LULC) change and is now characterized by citrus farming in the interior and municipalities on its eastern coast on the Atlantic Ocean. This LULC change has been made possible by the construction of an extensive …

Interactive Fitness Domains In Competitive Coevolutionary Algorithm, Atm Golam Bari

USF Tampa Graduate Theses and Dissertations

Evolutionary Algorithms (EA) have been successfully applied to a wide range of optimization and search problems where no mathematical model of the quality of a candidate solution is available. Interactive Evolutionary Algorithms (IEA) and Competitive Coevolutionary Algorithms (CCoEA) go one step further by being able to tackle problems where the only means to evaluate the quality of a candidate solution is via interactions. In a typical IEA, interactions take place between the solution being evolved and human evaluators. In a CCoEA, interactions take place between solutions themselves, without need for human interaction. This dissertation identifies computer-aided learning as an application …

The Paradox Of Urban Greening: Does It Harm The Very People Who Need It The Most?, Juliana Maantay

Sustainability Seminar Series

Urban greening and sustainability approaches are well accepted methods for improving the urban environment and combating the climate crisis. Cleaning up potentially contaminated lands and bringing them back into constructive public use is one of the benefits of greening. However, greening efforts may have unintended consequences, resulting in adverse social and economic impacts to the existing residents, who are often the most vulnerable urban populations. Spatial analyses of case study examples show that greening can spur “green gentrification.” Measures can be taken to integrate social equity objectives into urban sustainability planning, to mitigate gentrification, and to improve equitable distribution of …

Potential Economic Impacts Of Allocating More Land For Bioenergy Biomass Production In Virginia, Thomas O. Ochuodho, Janaki R. R. Alavalapati, Pankaj Lal, Domena A. Agyeman, Bernabas Wolde, Pralhad Burli

Pankaj Lal

The growing attention to renewable energy and rural development has created greater demand for production of biomass feedstock for bioenergy. However, forest growth rates and the amount of land in most existing forests may not be sufficient to sustainably supply the forest biomass required to support existing forest products industries and the expanding bioenergy industry. Additionally, concerns about agricultural land use competition have dampened expansion of biomass production on agricultural land base. One of the ways to meet the growing forest biomass feedstock demand for bioenergy production is by allocating currently marginal non-forested land for growing bioenergy feedstocks. In Virginia, …

Studying The Glacial Melt Of Mount Baker Using Remote Sensing (1999 - 2019), Cole Fletcher

Scholars Week

With rising temperatures glaciers around the globe are beginning to melt. Melting of large glaciers should be concerning as they can raise the present sea-level which could potentially put near sea-level urban areas underwater. We must observe the rate at which glaciers are retreating. Mountain glaciers are a good resource to observe as they do give a clear visual of how fast glaciers are retreating. This project hopes to give a good visual representation and quantitative measurement of how much glacial melt is occurring at Mt Baker in Washington, United States, in the last 20 years. This project will use …

Classifying Fiction And Non-Fiction Works Using Machine Learning, Rachna Gupta '21

Student Publications & Research

The objective of this project was to create a program that can determine whether an unknown text is a work of fiction or non-fiction using machine learning. Various datasets of speeches, ebooks, poems, scientific papers, and texts from Project Gutenberg and the Wolfram Example Data were utilized to train and test a Markov Chain machine learning model. A microsite was deployed with the final product that returns a probability of fictionality based on input from the user with 95% accuracy.

On The Linear Independence Of Finite Wavelet Systems Generated By Schwartz Functions Or Functions With Certain Behavior At Infinity, Abdelkrim Bourouihiya

Mathematics Faculty Articles

One of the motivations to state HRT conjecture on the linear independence of finite Gabor systems was the fact that there are linearly dependent Finite Wavelet Systems (FWS). Meanwhile, there are also many examples of linearly independent FWS, some of which are presented in this paper. We prove the linear independence of every three point FWS generated by a nonzero Schwartz function and with any number of points if the FWS is generated by a nonzero Schwartz function, for which the absolute value of the Fourier transform is decreasing at infinity. We also prove the linear independence of any FWS …

Centrosymmetric Stochastic Matrices, Lei Cao, Darian Mclaren, Sarah Plosker

Mathematics Faculty Articles

We consider the convex set Γ_m,n of m×n stochastic matrices and the convex set Γ^π_m,n ⊂Γ_m,n of m×n centrosymmetric stochastic matrices (stochastic matrices that are symmetric under rotation by 180 degrees). For Γ_m,n, we demonstrate a Birkhoff theorem for its extreme points and create a basis from certain (0,1)-matrices. For Γ^π_m,n, we characterize its extreme points and create bases, whose construction depends on the parity of m, using our basis construction for stochastic matrices. For each of Γ_m,n and Γ^π_m,n, we further characterize their extreme …

Spatial And Temporal Variation Of Offshore Wind Power And Its Values Along The Central California Coast, Yi-Hui Wang, Ryan K. Walter, Crow White, Matthew D. Kehrli, Stephen F. Hamilton, Patrick H. Soper, Benjamin I. Ruttenberg

Physics

The analysis of the spatiotemporal variability of wind power remains limited during the planning stage of an offshore wind farm. This study provides a framework to investigate how offshore wind power varies along the Central California Coast over diurnal and seasonal time scales, which is critical for reliability and functionality of the grid system. We find that offshore wind power in this region peaks during evening hours across all seasons and maximizes in spring and summer. The timing of peak offshore wind power production better aligns with that of peak demand across California than solar and land-based wind power production, …

The Role Of The Dispersion Parameter In Electrical Properties Of Highly Disordered Insulating Materials, Zachary Gibson

Physics Student Research

Charge transport in disordered solids can be described with use of a dispersion parameter. The dispersion parameter can be defined simply as either the thermal energy (low electric field regime) or the field energy (high field regime) scaled by the reciprocal of a characteristic energy of the material. A transitionary temperature and electric field are defined when the ratio of thermal or field energy over the characteristic energy is one, respectively. This indicates a transition from dispersive transport to normal transport. Dispersive transport can be described simply by the dispersion parameter for many disordered materials. Models involving the dispersion parameter …

Data Of Soil, Vegetation And Bird Species Found On Double-Crested Cormorant Colonies In The Southeastern United States, Leah Moran Veum, Brian S. Dorr, Katie Hanson-Dorr, R. J. Moore, Scott A. Rush

United States Department of Agriculture Wildlife Services: Staff Publications

This data article provides the methods and procedures followed to collect and analyse soil, vegetation and bird data on three different treatment islands in Guntersville Reservoir, Alabama. Samples were collected from randomly selected plot points from islands that were placed into three different treatment types: Colony (currently occupied by Double-crested Cormorants) (Phalacrocorax auritus; n 1⁄4 5), Historic (historically occupied by cormorants and currently abandoned; n 1⁄4 3) and Reference (never occupied by cormorants; n 1⁄4 4). We compared vegetation and tree metrics such as structure and diversity, as well as soil chemistry and bird diversity and communities among islands within …

Digital Addiction: A Conceptual Overview, Amarjit Kumar Singh, Pawan Kumar Singh

Library Philosophy and Practice (e-journal)

Abstract

Digital addiction referred to an impulse control disorder that involves the obsessive use of digital devices, digital technologies, and digital platforms, i.e. internet, video game, online platforms, mobile devices, digital gadgets, and social network platform. It is an emerging domain of Cyberpsychology (Singh, Amarjit Kumar and Pawan Kumar Singh; 2019), which explore a problematic usage of digital media, device, and platforms by being obsessive and excessive. This article analyses, reviewed the current research, and established a conceptual overview on the digital addiction. The research literature on digital addiction has proliferated. However, we tried to categories the digital addiction, according …

Energy Transition Modeling: Social And Technical Dynamics Of Moving To Renewable Energy, Lawrence Gottschamer

USF Tampa Graduate Theses and Dissertations

The majority of global electricity is generated using fossil fuels as an energy source, and the science linking fossil fuel combustion with negative environmental impacts is clear. Recognizing this link, decarbonizing the electricity system is a critical component of climate change mitigation. However, moving electricity generation, distribution, and end-use behavior patterns to renewable energy is a complex socio-technical energy transition challenge with a number of economic, policy, technological, societal and environmental barriers. Energy transition work tends to be siloed within these topics; ignoring complex socio-technical interdependencies impacting electricity system transition dynamics. This work fills the knowledge gap with a ‘systems …

Sundaas Story: A Mixed-Methods Study Of Household Sanitation Provisioning In Urban Informal Housing In India, Sarita Vijay Panchang

USF Tampa Graduate Theses and Dissertations

The aims of this research were to examine sanitation insecurity in urban informal housing through the lens of the built environment, social disparities, and health implications. While the Millennium Development Goals for halving the global proportion of people without access to safe drinking water were met ahead of schedule, progress fell short for sanitation, creating new objectives for the Sustainable Development Goals to be met in 2030. Much research in the Global South is dedicated to community-level sanitation promotion, but often presumes a rural rather than urban setting. Urban informal housing settings constitute a unique challenge due to the range …

Modeling Of Buildings With Electrochromic Windows And Thermochromic Roofs, Hua-Ting Kao

USF Tampa Graduate Theses and Dissertations

Air conditioning and heating have increased substantially during the past two decades. According to a survey, buildings consume about 73% of the total electricity in the United States, accounting for 41% of all other energy in the world. At the same time, building skin technologies are constantly improving. Electrochromic and thermochromic are two exciting new technologies that can help reduce the energy consumption of a building. The purpose of this work is to increase our understanding of how much the use of electrochromic (EC) and thermochromic (TC) technologies can reduce the energy consumption of residential and commercial buildings in two …

Nonideal Mhd Simulation Of Hl Tau Disk: Formation Of Rings, Xiao Hu, Zhaohuan Zhu, Satoshi Okuzumi, Xue-Ning Bai, Lile Wang, Kengo Tomida, James M. Stone

Physics & Astronomy Faculty Research

Recent high-resolution observations unveil ring structures in circumstellar disks. The origin of these rings has been widely investigated under various theoretical scenarios. In this work we perform global 3D nonideal MHD simulations including effects from both ohmic resistivity and ambipolar diffusion (AD) to model the HL Tau disk. The nonideal MHD diffusion profiles are calculated based on the global dust evolution calculation including sintering effects. Disk ionization structure changes dramatically across the snow line due to the change of dust size distribution close to the snow line of major volatiles. We find that accretion is mainly driven by disk wind. …

Transparent Solar Windows From Labs To Industry, Towards Smart Cities - Encyclopedia- Oct 2019.Pdf, Mohammad Nur-E-Alam, Mikhail Vasiliev, Kamal Alameh

Mikhail Vasiliev

Generation And Reactions Of A Benzodehydrotropylium Ion-Co2(Co)6 Complex, Mariam A. Mehdi, Eric A.C. Bushnell, Sahar Nikoo, James W. Gauld, James R. Green

Chemistry and Biochemistry Publications

A series of 7-methylenedehydrobenzo[7]annulen-5-ol hexacarbonyldicobalt complexes were generated by Hosomi-Sakurai reactions of allylsilanes containing o-alkynylarylaldehyde-Co₂(CO)₆ complexes. One of cyclization products was converted into its corresponding dihydrobenzo[7]annulen-7-ol hexacarbonyldicobalt complex, an immediate precursor to a benzodehydrotropylium-Co₂(CO)₆. The cation was generated in situ and reacted with four nucleophiles, and its aromatic stabilization determined by computational methods.

Relationships Between Soil Macroinvertebrates And Nonnative Feral Pigs (Sus Scrofa) In Hawaiian Tropical Montane Wet Forests, Nathaniel H. Wehr, Creighton M. Litton, Noa K. Lincoln, Steven C. Hess

United States National Park Service: Publications

Abstract Nonnative feral pigs (Sus scrofa) are recognized throughout the New World as a highly significant introduced species in terms of ecosystem alteration. Similarly, nonnative soil macroinvertebrates (e.g. earthworms, ground beetles) invade and alter the structure and function of native habitats globally. However, the relationship between feral pigs and soil macroinvertebrates remains largely unknown. This study analyzed relationships between these taxa using nine sites located inside and outside of feral pig management units representing a * 25 year chronosequence of removal in tropical montane wet forests in Hawai‘i. Soil macroinvertebrates were sampled from plots categorized as: actively trampled by feral …

Special Issue: Electrocatalysis And Fuel Cells, Shuangyin Wang

Journal of Electrochemistry

Around electrocatalysis and fuel cell, this album contains 7 research papers and reviews written by these teams with rich accumulation and influence in related research fields. This album partly reflects the research progress in the design, synthesis and performance of electrocatalysts in China. With the publication of this special issue, it is hoped that readers will have a better understanding of the current research situation in this field in China. To promote the further development of electrocatalytic chemistry and new fuel cell research in China.

A Facile Route To Synthesize Pt-Wo3 Nanosheets With Enhanced Electrochemical Performance For Her, Peng-Jie Jiang, Yi Lv, Chang-Miao Chen, Hong-Cheng He, Yong Cai, Ming Zhang

Journal of Electrochemistry

Platinum-tungsten trioxide (Pt-WO₃) nanosheets were synthesized on nickel foams (NFs) directly. As great conductive networks, NFs substrates could greatly improve the electrode performance of WO₃. The modified platinum nanoparticles not only enhanced the electron transformation of catalysts, but also increased the active sites for hydrogen evolution reaction (HER). Pt-WO₃/NF revealed a better catalytic activity than WO₃/NFs with a smaller Tafel slope (80 mV·dec^-1) and a lower overpotential of 72 mV at the current density of 10 mA·cm^-2. In addition, Pt-WO₃/NF showed great durability and stability during …

Nickel Selenide Derived From [Ni(En)3](Seo3) Complex For Efficient Electrocatalytic Overall Water Splitting, Dan-Dan Chen, Xue-Qing Gao, Hong-Fei Liu, Wei Zhang, Rui Cao

Journal of Electrochemistry

Electrocatalytic water splitting is considered as a promising technology for renewable energy. The development of efficient, stable, cost-effective, and bifunctional catalysts for both water reduction and oxidation has continued to face significant challenges. Herein, we report a robust and highly active nickel selenide (NiSe) spheres grown on carbon cloth (CC) by electrodeposition from a nickel selenite complex which is a single source containing both Ni and Se. A combination of two chemicals containing, separately, Ni and Se is used in traditional preparations of metal selenides, causing possible problems in the uniformity of the products. The as-prepared NiSe-EA/CC electrode exhibited electrocatalytic …

Preparations And Electrochemical Properties Of Co@Nc Nanocomposites Based On Zif-67, Xiao-Li Tan, Deng-Hong He, Xing-Wang Zhang

Journal of Electrochemistry

It is necessary to develop an inexpensive catalyst for the replacement of precious metal catalysts (such as RuO₂, IrO₂). In this article, the metal organic framework ZIF-67 was synthesized by solvothermal method at room temperature, and then the high temperature carbonization was used to prepare the nitrogen-doped carbon-based composite material Co@NC with the Co nanoparticle inside. The effects of the carbonization temperature on surface morphology, chemcial composition and electrocatalytic property were investigated. Most importantly, the Co@NC catalyst with the best morphology and structure was synthesized, and its catalytic activity and stability toward oxygen evolution reaction (OER) …

Influences Of Morphology And Nitrogen Doping On The Electrocatalytic Characteristics For Oxygen Reduction Reaction Of Nio/Rgo, Dong Liang, Heng-Yi Fang, Shuo Yao, Jie-Mei Yu, Zhao-Liang Zhang, Zhan-Kun Jiang, Xue-Ping Gao, Tai-Zhong Huang

Journal of Electrochemistry

In this research, the reduced graphene oxide (rGO) supported sheet-like NiO (NiO/rGO) and spherical-like NiO (NiO/N-rGO) catalysts for oxygen reduction reaction (ORR) were prepared. The structures, morphologies and chemical states of the two catalysts were characterized by X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electrochemical catalytic performance of the two catalysts for ORR were investigated by cyclic voltammetry (CV), Tafel, linear sweeping voltammetry (LSV), rotating disc electrode (RDE) and rotating ring disc electrode (RRDE) tests. Electrochemical results showed that the current density and onset potential (about 0.89 V) …

Preparation Of Nanostructural Mno-Porous Graphene Hybrid Material By Thermally-Driven Etching Of Mno For Lithium-Air Batteries, Juan Yang, Jun-Wei Lang, Peng Zhang, Bao Liu

Journal of Electrochemistry

In this paper, improving the surface morphology of graphene(GNSs) as designed concept. we describe a MnO/porous-graphene(MnO-PGNSs) was synthesized by a simple site-localized Mn²⁺ on GO (Mn-GO) by charge adsorption and then driving by high-temperature calcination, growing MnO nanoparticles and etching GNSs achieved on step. And Then focus on the key factors of influenced the etch hole formation are analyzed, founded the dispersion of Mn-GO; layer number of GO and calcination temperature also affected the formation of holes. In addition, the MnO-PGNSs as lithium-air battery cathode exhibits high reversible capacity compared with GNSs and PGNs and it is able to …

Three-Dimensional Porous Vn Octahedron Catalyst With High Electrocatalytic Efficiency Toward Hydrogen Evolution Reaction, Can Yin, Wei-Wei Fu, Ling Fang, Shi-Li You, Hui-Juan Zhang, Yu Wang

Journal of Electrochemistry

With the rapid development of China’s economy, the demand for energy is increasing, and environmental problems are becoming more and more serious. The development and utilization of highly-clean new energy fuel can effectively alleviate the energy crisis and environmental pollution. Nowadays, exploring high-efficiency, environment-friendly and low-cost catalysts remains the focus of research in the hydrogen evolution reaction (HER). In this research, firstly, we proposed a three-dimensional porous vanadium nitride (VN) with octahedral structure, which was prepared by a calcination treatment method. The VN catalyst showed a good electrocatalytic activity toward HER, involving a small overpotential of 94.0 mV at -10 …

Progress In Solar Photocatalytic Hydrogen Production, Zhi Wu, Lan Sun, Chang-Jian Lin

Journal of Electrochemistry

With the rapid development of human society and dramatically consumption of traditional energy, energy shortage and environmental pollution have become an important factor restricting the sustainable development of human society. At present, the development of clean and environmentally friendly renewable energy system has drawn much attention and becomes an important priority stratagem in the world. In many green and sustainable new energy projects, semiconductor-based photocatalytic hydrogen production technology which utilizes the available clean and renewable solar energy to prepare clean hydrogen energy is excepted to solve the crisis of energy shortage and environmental pollution, has become one of the most …

Investigations In Electrochemical Thermodynamic And Kinetic Properties Of As-Cast And As-Quenched Cemg10Ni2 Hydrogen Storage Alloys, Feng Hu, Li-Rong Luo, Yong-Zhi Li, Ting-Ting Zhai, Xin Zhao, Yang-Huan Zhang

Journal of Electrochemistry

In order to improve the electrochemical hydrogen storage properties of CeMg₁₀Ni₂ alloy, the rapid quenching technology was used to prepare CeMg₁₀Ni₂ alloys with nano-crystalline and amorphous structure. The microstructures of as-cast and as-spinning sample were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The electrochemical hydrogen storage properties were investigated by an automatic galvanostatic charging/discharging, high rate discharging (HRD), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques. The results revealed that the as-cast alloy was composed of multiphase structures. The as-quenched alloys were made up of nano-crystalline and/or amorphous structures, and the …

Great Success Of The 20th National Conference On Electrochemistry In China (Changsha)

Journal of Electrochemistry

No abstract provided.