Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

2019

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 1501 - 1530 of 15927

Full-Text Articles in Physical Sciences and Mathematics

Optimal Relaxation Weights For Multigrid Reduction In Time (Mgrit), Masumi Sugiyama Nov 2019

Optimal Relaxation Weights For Multigrid Reduction In Time (Mgrit), Masumi Sugiyama

Mathematics & Statistics ETDs

Based on current trends in computer architectures, faster compute speeds must come from increased parallelism rather than increased clock speeds, which are stagnate. This situation has created the well-known bottleneck for sequential time-integration, where each individual time-value (i.e., time-step) is computed sequentially. One approach to alleviate this and achieve parallelism in time is with multigrid. In this work, we consider the scheme known as multigrid-reduction-in-time (MGRIT), but note that there exist other parallel-in-time methods such as parareal and the parallel full approximation scheme in space and time (PFASST). MGRIT is a full multi-level method applied to the time dimension and …


Making Trees Count: Measurement And Reporting Of Agroforestry In Unfccc National Communications Of Non-Annex I Countries, Todd S. Rosenstock, Andreas Wilkes, Courtney Jallo, Nictor Namoi, Medha Bulusu, Marta Suber, Damaris Mboi, Rachmat Mulia, Elisabeth Simelton, Meryl Richards, Noel Gurwick, Eva Wollenberg Nov 2019

Making Trees Count: Measurement And Reporting Of Agroforestry In Unfccc National Communications Of Non-Annex I Countries, Todd S. Rosenstock, Andreas Wilkes, Courtney Jallo, Nictor Namoi, Medha Bulusu, Marta Suber, Damaris Mboi, Rachmat Mulia, Elisabeth Simelton, Meryl Richards, Noel Gurwick, Eva Wollenberg

Rubenstein School of Environment and Natural Resources Faculty Publications

Agroforestry—the integration of trees with crops and livestock—generates many benefits directly relevant to the UNFCCC's Koronivia Joint Work on Agriculture, including: (i) building resilience, (ii) increasing soil carbon and improving soil health, (iii) providing fodder and shade for sustainable livestock production and (iv) diversifying human diets and economic opportunities. Despite its significance to the climate agenda, agroforestry may not be included in measurement, reporting and verification (MRV) systems under the UNFCCC. Here we report on a first appraisal of how agroforestry is treated in national MRV systems under the UNFCCC. We examined national communications (NCs) and Nationally Determined Contributions (NDCs) …


The Firece Green Fire: Vol. 10 Issue 10, Wofford College Environmental Studies Program Nov 2019

The Firece Green Fire: Vol. 10 Issue 10, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.


Lisa For Cosmologists: Calculating The Signal-To-Noise Ratio For Stochastic And Deterministic Sources, Tristan L. Smith, R. R. Caldwell Nov 2019

Lisa For Cosmologists: Calculating The Signal-To-Noise Ratio For Stochastic And Deterministic Sources, Tristan L. Smith, R. R. Caldwell

Physics & Astronomy Faculty Works

We present the steps to forecast the sensitivity of the Laser Interferometer Space Antenna (LISA) to both a stochastic gravitational wave background and deterministic wave sources. We show how to use these expressions to estimate the precision with which LISA can determine parameters associated with these sources. Tools are included to enable easy calculation of the signal-to-noise ratio and draw sensitivity curves. Benchmark values are given for easy comparison and checking of methods in the case of three worked examples. The first benchmark is the threshold stochastic gravitational wave background ΩGWh2 that LISA can observe. The second is the signal-to-noise …


Synthesis, Optical, And Thermal Properties Of 2,4,6-Tris(4-Substituted Phenyl)Pyrylium Tosylates And Triflimides, Pradip Kumar Bhowmik, Christina Inbok Lee, Jung Jae Koh, Haesook Han, Ahamed Jubair, Vladimir Kartazaev, Swapan Kumar Gayen Nov 2019

Synthesis, Optical, And Thermal Properties Of 2,4,6-Tris(4-Substituted Phenyl)Pyrylium Tosylates And Triflimides, Pradip Kumar Bhowmik, Christina Inbok Lee, Jung Jae Koh, Haesook Han, Ahamed Jubair, Vladimir Kartazaev, Swapan Kumar Gayen

Chemistry and Biochemistry Faculty Research

A group of five 2,4,6-tris(4-substituted phenyl)pyrylium tosylates were synthesized in one-pot reaction from para-substituted benzaldehyde and para-substituted acetophenones using tosic acid as a condensing agent. The tosylate salts were converted to the corresponding triflimide salts by metathesis reactions. Chemical structures, as well as optical spectroscopic and thermal properties of these salts were studied using pertinent experimental techniques. Trimethyl- and trihalo-substituted pyrylium salts emitted strong blue light with peaks in the 456 nm–479 nm range and trimethoxy-pyrylium salts emitted intense green light with maxima around 526 nm in acetonitrile solution. Quantum yields of the solutions were rather low, but the salts …


Hierarchical Conjugated Polymer Systems Prepared By Controlled Chain-Growth Polymerization, Chunwa Peter Kei Nov 2019

Hierarchical Conjugated Polymer Systems Prepared By Controlled Chain-Growth Polymerization, Chunwa Peter Kei

LSU Doctoral Dissertations

π-Conjugated polymer materials may have a significant economic impact on society by providing means for designing affordable, flexible, and portable organic electronic devices. Their successful commercialization will depend on major scientific advancements, which will challenge human society to seek out ever more detailed and fundamental processes to command. Controlled polymerization affords such a power; allowing for the design of meticulous and precisely defined systems granting detailed insight into structure-property relationships in the polymer materials and bettering understanding of novel physical phenomena.

This dissertation primarily focuses on development and preparation of well-defined hierarchically organized macromolecular systems. The novel chain-growth polymerization methodologies …


Reputation-Aware Trajectory-Based Data Mining In The Internet Of Things (Iot), Samia Tasnim Nov 2019

Reputation-Aware Trajectory-Based Data Mining In The Internet Of Things (Iot), Samia Tasnim

FIU Electronic Theses and Dissertations

Internet of Things (IoT) is a critically important technology for the acquisition of spatiotemporally dense data in diverse applications, ranging from environmental monitoring to surveillance systems. Such data helps us improve our transportation systems, monitor our air quality and the spread of diseases, respond to natural disasters, and a bevy of other applications. However, IoT sensor data is error-prone due to a number of reasons: sensors may be deployed in hazardous environments, may deplete their energy resources, have mechanical faults, or maybe become the targets of malicious attacks by adversaries. While previous research has attempted to improve the quality of …


Realistic Sensitivity Curves For Pulsar Timing Arrays, J. S. Hazboun, J. D. Romano, Tristan L. Smith Nov 2019

Realistic Sensitivity Curves For Pulsar Timing Arrays, J. S. Hazboun, J. D. Romano, Tristan L. Smith

Physics & Astronomy Faculty Works

We construct realistic sensitivity curves for pulsar timing array searches for gravitational waves, incorporating both red and white noise contributions to individual pulsar noise spectra, and the effect of fitting to a pulsar timing model. We demonstrate the method on both simulated pulsars and a realistic array consisting of a subset of NANOGrav pulsars used in recent analyses. A comparison between the results presented here and measured upper limit curves from actual analyses shows agreement to tens of percent. The resulting sensitivity curves can be used to assess the detectability of predicted gravitational-wave signals in the nanohertz frequency band in …


Evidence For Large Holocene Earthquakes Along The Denali Fault In Southwest Yukon, Canada, Andrée Blais-Stevens, John J. Clague, Janice Brahney, Panya Lipovsky, Peter J. Haeussler, Brian Menounos Nov 2019

Evidence For Large Holocene Earthquakes Along The Denali Fault In Southwest Yukon, Canada, Andrée Blais-Stevens, John J. Clague, Janice Brahney, Panya Lipovsky, Peter J. Haeussler, Brian Menounos

Watershed Sciences Faculty Publications

The Yukon–Alaska Highway corridor in southern Yukon is subject to geohazards ranging from landslides to floods and earthquakes on faults in the St. Elias Mountains and Shakwak Valley. Here we discuss the late Holocene seismic history of the Denali fault, located at the eastern front of the St. Elias Mountains and one of only a few known seismically active terrestrial faults in Canada. Holocene faulting is indicated by scarps and mounds on late Pleistocene drift and by tectonically deformed Pleistocene and Holocene sediments. Previous work on trenches excavated against the fault scarp near the Duke River reveals paleoseismic sediment disturbance …


Use Of Spectrofluorometry To Detect Petroleum Hydrocarbons In The Marine Environment, Mary Iris Abercrombie Nov 2019

Use Of Spectrofluorometry To Detect Petroleum Hydrocarbons In The Marine Environment, Mary Iris Abercrombie

USF Tampa Graduate Theses and Dissertations

The genesis of this research was the Deepwater Horizon oil spill, which discharged petroleum and gas into the Gulf of Mexico for 87 days in 2010. High-resolution fluorescence spectroscopy was employed for the detection of petroleum in seawater samples following the oil spill. Fluorescence arises from the chemical structure of π-bonding in C=C bonds, especially those in aromatic structures. Spectrofluorometry was also used to observe and track the formation of petroleum plumes in seawater undergoing controlled physical dispersion in a wave tank, both with and without the addition of chemical dispersant. Further, the changing fluorescence characteristics of a broad range …


Trajectory Privacy Preservation And Lightweight Blockchain Techniques For Mobility-Centric Iot, Abdur Bin Shahid Nov 2019

Trajectory Privacy Preservation And Lightweight Blockchain Techniques For Mobility-Centric Iot, Abdur Bin Shahid

FIU Electronic Theses and Dissertations

Various research efforts have been undertaken to solve the problem of trajectory privacy preservation in the Internet of Things (IoT) of resource-constrained mobile devices. Most attempts at resolving the problem have focused on the centralized model of IoT, which either impose high delay or fail against a privacy-invading attack with long-term trajectory observation. These proposed solutions also fail to guarantee location privacy for trajectories with both geo-tagged and non-geo-tagged data, since they are designed for geo-tagged trajectories only. While a few blockchain-based techniques have been suggested for preserving trajectory privacy in decentralized model of IoT, they require large storage capacity …


Charged Fusion Product Plasma Diagnostics In Spherical Tokamaks, Alexander Netepenko Nov 2019

Charged Fusion Product Plasma Diagnostics In Spherical Tokamaks, Alexander Netepenko

FIU Electronic Theses and Dissertations

Charged fusion products from the D(d,p)t reaction, protons (p) and tritons (t), can be detected to obtain time and position dependent information on the fusion reaction profile in plasmas heated with neutral particles beams. We have developed a prototype instrument consisting of charged particle detectors with ion-implanted-silicon surface barrier detectors. Each detector is combined with two replaceable collimators in such a way that it can accept protons and tritons emitted from a well-defined area inside the plasma. The detectors thus provide curved views across the plasma volume.

Combining the data of all six detectors allows one to study changes in …


The Activity And Structure Of Cu2+-Biomolecules In Disease And Disease Treatment, Darrell Cole Cerrato Nov 2019

The Activity And Structure Of Cu2+-Biomolecules In Disease And Disease Treatment, Darrell Cole Cerrato

USF Tampa Graduate Theses and Dissertations

Despite its relatively low concentration in the human body, copper is an essential transition metal ion. Under normal circumstances, it is a well-regulated trace element that is introduced via diet or environment depending on the organism. Its strong reactivity and binding to some biologically essential chemicals can be detrimental to the host organism. Herein the oxidative chemistry of copper and its possible prevention in humans and agricultural organisms is discussed, as well as the potential avenues as metal-targeting disease treatment via novel-peptide and peptoid products.

In the first study, copper is implicated in the progression and onset of Alzheimer’s disease. …


Using Natural Phenomena To Study The Ionosphere, Joseph Benjamin Malins Nov 2019

Using Natural Phenomena To Study The Ionosphere, Joseph Benjamin Malins

Physics & Astronomy ETDs

This dissertation explores novel techniques for observing the ionosphere using natural signals. The ionosphere is a region of plasma hundreds of kilometers above the Earth that affects communication and remote sensing applications across the world. Traditional techniques for observing the ionosphere involve using man made radio signals, either to reflect the signal at HF frequencies or to pass several signals through the ionosphere and compare the difference the ionosphere makes in the signals. However, such techniques are limited by the ability of equipment to produce these signals and by the numerous laws and regulations governing transmission of signals in the …


A Note On Graphs With Prescribed Orbit Structure, Abbe Mowshowitz, Matthias Dehmer, Frank Emmert-Streib Nov 2019

A Note On Graphs With Prescribed Orbit Structure, Abbe Mowshowitz, Matthias Dehmer, Frank Emmert-Streib

Publications and Research

No abstract provided.


Information Extraction From Primary Care Visits To Support Patient-Provider Interactions, Daniel Baruch Gutstein Nov 2019

Information Extraction From Primary Care Visits To Support Patient-Provider Interactions, Daniel Baruch Gutstein

College of Computing and Digital Media Dissertations

The extent of electronic health record systems usage in clinical settings has affected the dynamic between clinicians and patients and has thus been connected to physician morale and the quality of care patients receive. Recent research has also uncovered a correlation between physician burnout and negative physician attitudes electronic health record systems. In order to begin exploring the nature of the relationship between electronic health record usage, physician burnout, and patient care, it is necessary to first analyze patient-provider interactions within the context of verbal features such as turn-taking and non-verbal features such as eye-contact. While previous works have sought …


Measurements Of The 16c + 12c And 16c + 13c Fusion Cross Sections With Implications For Astrophysics, Ashley Ann Hood Nov 2019

Measurements Of The 16c + 12c And 16c + 13c Fusion Cross Sections With Implications For Astrophysics, Ashley Ann Hood

LSU Doctoral Dissertations

The fusion of neutron-rich nuclei is of interest to nuclear astrophysics and nuclear structure. X-ray superbursts are powered by runaway thermonuclear burning deep inside of a neutron star, where heating from the pycnonuclear fusion of neutron-rich isotopes is an important heat source. Experimental measurements of fusion cross sections of neutron-rich isotopes have provided insights regarding nucleon transfer and nuclear structure properties affecting fusion. Recently, the 15C + 12C total fusion cross section was measured using a 15C beam produced by the in-flight beam production facility, which is part of the Argonne Tandem LINAC Accelerator System (ATLAS) at …


Effect Of Atypical Protein Kinase C Inhibitor (Dnda) On Cell Proliferation And Migration Of Lung Cancer Cells, Raja Reddy Bommareddy Nov 2019

Effect Of Atypical Protein Kinase C Inhibitor (Dnda) On Cell Proliferation And Migration Of Lung Cancer Cells, Raja Reddy Bommareddy

USF Tampa Graduate Theses and Dissertations

Lung cancer is the second most common cancer, and it is the leading cause of cancer death in both men and women. Elevated levels of PKC-ι and FAK are implicated in the progression of lung cancer and involved in cell proliferation, apoptosis, cell survival, and cell migration processes. Lung cancer diagnosis typically occurs in the late stages, which limits the treatment options. Hence, there is a dire need to develop drugs that are effective and safe to treat lung cancers. We used a novel aPKC inhibitor named DNDA (3,4-amino-2,7 napthalene disulfonic acid) to study the role of atypical PKCs (aPKCs) …


The Peculiar Nature Of Florida’S Sandhill Wetlands, Ponds & Lakes— Their Ecohydrology, Relationship With The Regional Aquifer & Importance Within The Landscape., Renae Starr Nowicki Nov 2019

The Peculiar Nature Of Florida’S Sandhill Wetlands, Ponds & Lakes— Their Ecohydrology, Relationship With The Regional Aquifer & Importance Within The Landscape., Renae Starr Nowicki

USF Tampa Graduate Theses and Dissertations

This dissertation explores the ecohydrology of Florida’s peculiar and poorly studied sandhill wetland and water features, particularly those located in west-central Florida. The primary research goals include: compilation and summarization of the available ecohydrologic information for features across Florida; comparison of water level and water geochemistry data between sandhill wetlands and waters and the regional aquifer to provide evidence of regional hydrologic control; and use of geophysical applications to examine the hydraulic connections between sandhill wetlands and waters and the regional aquifer.

From this research, a natural history of sandhill wetland and water ecohydrology is presented, highlighting: the differences between …


Machine Learning To Quantitate Neutrophil Netosis, Laila Elsherif, Noah Sciaky, Carrington A. Metts, Md. Modasshir, Ioannis Rekleitis, Christine A. Burris, Joshua A. Walker, Nadeem Ramadan, Tina M. Leisner, Stephen P. Holly, Martis W. Cowles, Kenneth I. Ataga, Joshua N. Cooper, Leslie V. Parise Nov 2019

Machine Learning To Quantitate Neutrophil Netosis, Laila Elsherif, Noah Sciaky, Carrington A. Metts, Md. Modasshir, Ioannis Rekleitis, Christine A. Burris, Joshua A. Walker, Nadeem Ramadan, Tina M. Leisner, Stephen P. Holly, Martis W. Cowles, Kenneth I. Ataga, Joshua N. Cooper, Leslie V. Parise

Faculty Publications

We introduce machine learning (ML) to perform classifcation and quantitation of images of nuclei from human blood neutrophils. Here we assessed the use of convolutional neural networks (CNNs) using free, open source software to accurately quantitate neutrophil NETosis, a recently discovered process involved in multiple human diseases. CNNs achieved >94% in performance accuracy in diferentiating NETotic from non-NETotic cells and vastly facilitated dose-response analysis and screening of the NETotic response in neutrophils from patients. Using only features learned from nuclear morphology, CNNs can distinguish between NETosis and necrosis and between distinct NETosis signaling pathways, making them a precise tool for …


Construction Of G-Quadruplexes Via Self-Assembly: Enhanced Stability And Unique Properties, Ying He Nov 2019

Construction Of G-Quadruplexes Via Self-Assembly: Enhanced Stability And Unique Properties, Ying He

USF Tampa Graduate Theses and Dissertations

This dissertation mainly contains three parts: 1) The construction of well-defined G8-octamers through the monomer conformational design. 2) The construction of cross-layer interactions in the G8-octamer for enhanced stability in H-bond competitive solvents. 3) Design and synthesis of 8-triazole guanosine with photoluminescent properties.

Through the structural conformational design, we have developed a new class of guanosine derivatives with modification on guanine (8-aryl) and ribose (2’,3’-isopropylidene). This unique design has led to the formation of the first discrete G8-octamer with structure characterized by NMR, MS and single crystal X-ray diffraction. The selectivity between monovalent (K+) and divalent cat-ions (Ba2+ and Sr2+) …


First-Principles Simulations Of Materials Under Extreme Conditions, Kien Nguyen Cong Nov 2019

First-Principles Simulations Of Materials Under Extreme Conditions, Kien Nguyen Cong

USF Tampa Graduate Theses and Dissertations

The investigation of materials at extreme conditions of high pressure and temperature (high-PT), has been one of the greatest scientific endeavors in condensed mater physics, chemistry, astronomy, planetary, and material sciences. Being subjected to high-PT conditions, materials exhibit dramatic changes in both atomic and electronic structure resulting in an emergence of exceptionally interesting phenomena including structural and electronic phase transitions, chemical reactions, and formation of novel compounds with never-previously observed physical and chemical properties. Although new exciting experimental developments in static and dynamic compression combined with new diagnostics/characterization methods allow to uncover new processes and phenomena at high P-T conditions, …


Stock@>> Https://Slimtonediets.Com/Perfect-Keto-Max/, Jamesrtq Jamesrtq Nov 2019

Stock@>> Https://Slimtonediets.Com/Perfect-Keto-Max/, Jamesrtq Jamesrtq

Jamesrtq Jamesrtq


Perfect Keto Max weight reduction pills guarantee to help you in three different ways. They can profess to be a quick weight reduction sponsor, fat eliminator and digestion supporter across the board. This item utilizes Perfect Keto MaxNES to evidently trigger ketosis, you need to quit eating carbs. The Perfect Keto Max comes as the holder with around 60 tablets. It is counsel that a normal individual should take 2 tablets of this enhancement every day.


Managing Overheads In Asynchronous Many-Task Runtime Systems, Bibek Wagle Nov 2019

Managing Overheads In Asynchronous Many-Task Runtime Systems, Bibek Wagle

LSU Doctoral Dissertations

Asynchronous Many-Task (AMT) runtime systems are based on the idea of dividing an algorithm into small units of work, known as tasks. The runtime system is then responsible for scheduling and executing these tasks in an efficient manner by taking into account the resources provided to it and the associated data dependencies between the tasks. One of the primary challenges faced by AMTs is managing such fine-grained parallelism and the overheads associated with creating, scheduling and executing tasks. This work develops methodologies for assessing and managing overheads associated with fine-grained task execution in HPX, our exemplar Asynchronous Many-Task runtime system. …


2019 Women In Science Conference Program, Chicago Chec Nov 2019

2019 Women In Science Conference Program, Chicago Chec

Women in Science Conference

The Women in Science Conference celebrates women in the sciences. This year, the conference focuses on women in the field of chemistry, and will include keynote and plenary speakers, a career panel, a scientific art and media display and competition, hands-on chemistry-based learning activities, and a theater performance about Marie Curie by alumna Maria Bakalis.


Amphiphilic Block Copolymer Micelles In Selective Solvents: The Effect Of Solvent Selectivity On Micelle Formation, Labeesh Kumar, Andriy Horechyy, Eva Bittrich, Bhanu Nandan, Petra Uhlmann, Andreas Fery Nov 2019

Amphiphilic Block Copolymer Micelles In Selective Solvents: The Effect Of Solvent Selectivity On Micelle Formation, Labeesh Kumar, Andriy Horechyy, Eva Bittrich, Bhanu Nandan, Petra Uhlmann, Andreas Fery

Chemistry Department: Faculty Publications

We investigated the micellar behavior of a series of asymmetric polystyrene-block-poly (4-vinylpyridine) (PS-b-P4VP) block copolymers in different P4VP-selective alcoholic solvents. The micellar behavior was further correlated with the spectroscopic ellipsometry results obtained on swelling of PS and P4VP polymer films in the corresponding solvent vapors. The time-resolved (in situ) dynamic light scattering (DLS) measurements, in combination with (ex situ) electron microscopy imaging, revealed information about the aggregation state of PS-b-P4VP BCP in different alcohols and the effect of heat treatment. The ellipsometry measurements allowed us to estimate the difference in solvent selectivity toward PS/P4VP pair. Both DLS and ellipsometric studies …


Mapping Crustal Shear Wave Velocity Structure And Radial Anisotropy Beneath West Antarctica Using Seismic Ambient Noise, J. P. O'Donnell, Audrey D. Huerta, J. Paul Winberry Nov 2019

Mapping Crustal Shear Wave Velocity Structure And Radial Anisotropy Beneath West Antarctica Using Seismic Ambient Noise, J. P. O'Donnell, Audrey D. Huerta, J. Paul Winberry

All Faculty Scholarship for the College of the Sciences

Using 8- to 25-s-period Rayleigh and Love wave phase velocity dispersion data extracted from seismic ambient noise, we (i) model the 3-D shear wave velocity structure of the West Antarctic crust and (ii) map variations in crustal radial anisotropy. Enhanced regional resolution is offered by the UK Antarctic Seismic Network. In the West Antarctic Rift System (WARS), a ridge of crust ∼26–30km thick extending south from Marie Byrd Land separates domains of more extended crust (∼22km thick) in the Ross and Amundsen Sea Embayments, suggesting along-strike variability in the Cenozoic evolution of the WARS. The southern margin of the WARS …


Evolution Of A Relativistic Electron Beam For Tracing Magnetospheric Field Lines, Andrew T. Powis, Peter Porazik, Michael Greklek-Mckeon, Kailas Amin, David Shaw, Igor D. Kaganovich, Jay R. Johnson, Ennio Sanchez Nov 2019

Evolution Of A Relativistic Electron Beam For Tracing Magnetospheric Field Lines, Andrew T. Powis, Peter Porazik, Michael Greklek-Mckeon, Kailas Amin, David Shaw, Igor D. Kaganovich, Jay R. Johnson, Ennio Sanchez

Faculty Publications

Tracing magnetic field-lines of the Earth's magnetosphere using beams of relativistic electrons will open up new insights into space weather and magnetospheric physics. Analytic models and a single-particle-motion code were used to explore the dynamics of an electron beam emitted from an orbiting satellite and propagating until impact with the Earth. The impact location of the beam on the upper atmosphere is strongly influenced by magnetospheric conditions, shifting up to several degrees in latitude between different phases of a simulated storm. The beam density cross-section evolves due to cyclotron motion of the beam centroid and oscillations of the beam envelope. …


The Use Of Social Media In Emergency Management By Public Agencies And Non-Governmental Organizations: Lessons Learned From Areas Affected By Hurricanes Isaac, Sandy, And Harvey, Ryan Hamilton Kirby Nov 2019

The Use Of Social Media In Emergency Management By Public Agencies And Non-Governmental Organizations: Lessons Learned From Areas Affected By Hurricanes Isaac, Sandy, And Harvey, Ryan Hamilton Kirby

LSU Doctoral Dissertations

Natural disasters are increasingly costly for the United States. The literature suggests emergency managers may improve disaster outcomes and enhance disaster resilience by supplementing their official public-communications methods with more bi-directional communication tactics using social media. This study aims to understand how social media is used within the “whole community” of emergency management in areas affected by recent hurricanes. The first research objective examines how social media is used by governmental and non-governmental organizations across the four phases of emergency management (preparedness, response, recovery, mitigation). The second objective is to identify challenges governmental and non-governmental groups have encountered and strategies …


The Effects Of Temperature On The Yields Of Aliphatic And Aromatic Products From The Supercritical Pyrolysis Of 1-Octene, Elizabeth Anne Hurst Nov 2019

The Effects Of Temperature On The Yields Of Aliphatic And Aromatic Products From The Supercritical Pyrolysis Of 1-Octene, Elizabeth Anne Hurst

LSU Doctoral Dissertations

Prior to their combustion, fuels for future high-speed aircraft are expected to experience supercritical conditions, leading to the production of polycyclic aromatic hydrocarbons (PAH), precursors to solid carbonaceous deposits, via pyrolytic reactions. These solid deposits can clog fuel-transfer lines, causing unsafe aircraft operation. To prevent the formation of fuel-line deposits, it is critical to understand the reaction pathways that lead to PAH formation in the supercritical fuel pyrolysis environment.

To better understand the role of large 1-alkenes in PAH formation, supercritical pyrolysis experiments with model fuel 1-octene, a representative 1-alkene product from supercritical n-alkane pyrolysis, have been performed. The …