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Investigation Of Subsurface Stratigraphy And Groundwater Dynamics In The Mississippi River Delta, An Li Oct 2019

Investigation Of Subsurface Stratigraphy And Groundwater Dynamics In The Mississippi River Delta, An Li

LSU Doctoral Dissertations

The Mississippi River Delta (MRD) is socioeconomically important to the state of Louisiana and the United States. Various types of land-water system data have been collected in the MRD. However, very few efforts have been made to utilize these datasets in modeling regional stratigraphy and groundwater dynamics in the MRD, especially for the upper 50 m of the depth. In this interval of depth, the Mississippi River and surrounding interdistributary bays intensively interact with the groundwater system. The lack of knowledge in regional stratigraphy and groundwater dynamics hinder an understanding of how hydrogeological setting affects processes such as surface-groundwater interaction, …


Tick Control Methods For Amblyomma Americanum In Virginia: Applications And Modeling, Alexis Lynn White Oct 2019

Tick Control Methods For Amblyomma Americanum In Virginia: Applications And Modeling, Alexis Lynn White

Biological Sciences Theses & Dissertations

Tick-borne diseases continue to increase in the United States, and yet no comprehensive method of tick control currently exists. The lone star tick, Amblyomma americanum, is an aggressive human-biting tick and vector of several pathogens which effect both humans and other animals. Standard control methods do not work as well for A. americanum as they do for the more commonly studied blacklegged tick, Ixodes scapularis. TickBot, a tick-killing robot, is a potential method to control A. americanum that lures ticks to its path with carbon dioxide and the ticks die from contact with a permethrin-treated cloth that is …


Modeling And Characterization Of A Ring-Resonator Based Silicon Photonic Sensor On Silicon-On-Insulator (Soi), Gwangho Choi May 2019

Modeling And Characterization Of A Ring-Resonator Based Silicon Photonic Sensor On Silicon-On-Insulator (Soi), Gwangho Choi

Graduate Theses - Physics and Optical Engineering

The purpose of this work is to build silicon photonic devices and verify their functionalities. In particular, the structure of a ring resonator (RR) is analyzed and applied to various silicon photonic application in sensing. Silicon waveguides, grating couplers, directional couplers, and RRs are fabricated on the silicon-on-insulator (SOI) wafer. Geometrical parameters and optical properties of the silicon devices are studied and also applied to the design of the aforementioned devices. The waveguide dimensions and, optical properties of the silicon waveguide such as dispersion and effective-index are examined. The RRs are made of a series of straight and bent waveguides …


Reconstructing Barrier Island Behavior From Overstepped Deposits And Relict Onshore Morphology : Modeling And Field Approaches, Daniel James Ciarletta May 2019

Reconstructing Barrier Island Behavior From Overstepped Deposits And Relict Onshore Morphology : Modeling And Field Approaches, Daniel James Ciarletta

Theses, Dissertations and Culminating Projects

Barrier Islands comprise 10% of the Earth’s shorelines, fringing every continent except Antarctica. Despite their ubiquity, much about the medium to long-term evolution of these coastal systems remain poorly understood, mostly due to the destruction of the geologic record as barriers migrate landward under the influence of rising sea level. Even where modern barriers and related strandplain systems have prograded and regressed, leaving evidence of their former geometries in the form of relict shorelines, field investigations often require intensive labor and time commitments to interpret past evolution. In this work, several investigations are undertaken to use novel numerical modeling techniques …


Selection Of Best Sites For Aquifer Storage And Recovery In The Eastern District Of Abu Dhabi Emirate, United Arab Emirates, Karim Ali Mahfouz Abdou Khalil May 2019

Selection Of Best Sites For Aquifer Storage And Recovery In The Eastern District Of Abu Dhabi Emirate, United Arab Emirates, Karim Ali Mahfouz Abdou Khalil

Theses

The Emirate of Abu Dhabi relied on groundwater as the main source of fresh water for several decades in the past. This resulted in the deterioration of the non-renewable groundwater aquifers; and thus, desalination plants have become the major source of freshwater supply in the United Arab Emirates (UAE). Diminishing natural groundwater is a serious threat to freshwater security in arid regions. Because UAE has the world’s highest per capita water consumption rate, more than 70 desalination plants have been built in the last two decades. A major concern, therefore, is the vulnerability of these desalination plants to pollution and …


Capture Zone Analysis Of A Wellfield To Assess Contaminant Transport, Prince Kojo Oware Apr 2019

Capture Zone Analysis Of A Wellfield To Assess Contaminant Transport, Prince Kojo Oware

Theses and Dissertations

Radium is a common contaminant to the deep Cambrian- Ordovician aquifer in northern Illinois. Deep groundwater aquifers are used as fresh water resource in many parts of the world. Due to overuse, increase in salinity, natural and human-driven contamination, sustainability of these aquifer systems is uncertain. The purpose of this study is to better understand the groundwater flow system in deep bedrock aquifers in northern Illinois, and its control on the radium contamination in Rochelle’s Public Water Supply Wells (PWSW). We have tested two hypotheses: (1) the Radium (Ra) transport is driven by large pumping centers that interrupt groundwater flow …


Thermal Maturation Modeling Of The Michigan Basin, Jack H. Hybza Apr 2019

Thermal Maturation Modeling Of The Michigan Basin, Jack H. Hybza

Masters Theses

Given present day heat flow and burial depths in the Michigan Basin, hydrocarbons should be immature. However, oil and gas are abundant within the basin. Our hypothesis is that thermal maturation distributions in the Michigan Basin can be explained by variations in proximity to the Midcontinent Rift (MCR) system, thermal cooling, crustal convection, high temperature fluid advection, and eroded overburden.

For each of the seven wells in this study, a geohistory plot is coupled with a range of geodynamic models to calculate the thermal and maturation histories of each sediment unit within the well. Backstripping was used to generate basement …


Full-Waveform Inversion Of Common-Offset Ground Penetrating Radar (Gpr) Data, Sajad Jazayeri Mar 2019

Full-Waveform Inversion Of Common-Offset Ground Penetrating Radar (Gpr) Data, Sajad Jazayeri

USF Tampa Graduate Theses and Dissertations

Maintenance of aging buried infrastructure and reinforced concrete are critical issues in the United States. Inexpensive non-destructive techniques for mapping and imaging infrastructure and defects are an integral component of maintenance. Ground penetrating radar (GPR) is a widely-used non-destructive tool for locating buried infrastructure and for imaging rebar and other features of interest to civil engineers. Conventional acquisition and interpretation of GPR profiles is based on the arrival times of strong reflected/diffracted returns, and qualitative interpretation of return amplitudes. Features are thereby generally well located, but their material properties are only qualitatively assessed. For example, in the typical imaging of …


Lightning Prediction Using Recurrent Neural Networks, Dominick V. Speranza Mar 2019

Lightning Prediction Using Recurrent Neural Networks, Dominick V. Speranza

Theses and Dissertations

Cape Canaveral Air Force Station (CCAFS), Kennedy Space Center (KSC), and Patrick Air Force Base (PAFB) all reside in the thunderstorm capital of the United States. According to the Florida Climate Center, these installations experience more thunderstorms per year than any other place in the United States. It is the mission of the 45th Weather Squadron to provide timely and accurate warnings of weather conditions such as lightning that pose a risk to assets and personnel CCAFS, KSC and PAFB. To aid 45th Weather Squadron forecasters, a network of 30 Electric Field Mills (EFM) was installed in the area in …


Analytic Modeling Of Eccentric Binary Black Holes : From Inspiral To Merger, Dillon Paige Buskirk Jan 2019

Analytic Modeling Of Eccentric Binary Black Holes : From Inspiral To Merger, Dillon Paige Buskirk

Theses, Dissertations and Capstones

The orbital evolution of black hole binaries is described by two main phases: the inspiral and the merger. Using the post-Newtonian (PN) theory for the inspiral phase of the binary, we build up a Mathematica script to obtain strain waveforms for the inspiral. We expand our previous inspiral formulation to include eccentric orbits, which greatly complicates the calculations. Since this model breaks down as the two bodies approach merger, a separate model for the merger and ring-down is required. This part of the evolution is highly non-linear and numerical relativity (NR) is required to simulate this problem. However, this is …


Urban Water Demand In Arid-Regions: Modeling And Forecasting Climatic And Economic Effects, Tallen Ashley Capt Jan 2019

Urban Water Demand In Arid-Regions: Modeling And Forecasting Climatic And Economic Effects, Tallen Ashley Capt

Open Access Theses & Dissertations

Water demand is an ever-growing concern for many municipalities around the world and understanding the driving forces of demand is critical to ensure sustainability. The goal of this research was to develop mechanistic models of urban water demand that could be used as decision support tools for regional water managers. This Dissertation research focused on modeling water consumption in El Paso, Texas at the daily and annual time scale for use in a long-term forecast. The Dissertation is divided into three major chapters: the first two chapters describe independent models on (1) meteorological and (2) economic effects, respectively. The third …


Predicting How People Vote From How They Tweet, Rao B. Vinnakota Jan 2019

Predicting How People Vote From How They Tweet, Rao B. Vinnakota

Senior Projects Spring 2019

In 2016 Donald Trump stunned the nation and not a single pollster predicted the outcome. For the last few decades, pollsters have relied on phone banking as their main source of information. There is reason to believe that this method does not present the complete picture it once did due to several factors--less landline usage, a younger and more active electorate, and the rise of social media. Social media specifically has grown in prominence and become a forum for political debate. This project quantitatively analyzes political twitter data and leverages machine learning techniques such as Naive-Bayes to model election results. …


A Coupled Modeling Framework For Allocation Design In Land-Use And Land-Cover Changes To Optimize Biofuel Feedstock Production, Ana C. Cram Jan 2019

A Coupled Modeling Framework For Allocation Design In Land-Use And Land-Cover Changes To Optimize Biofuel Feedstock Production, Ana C. Cram

Open Access Theses & Dissertations

Environmental awareness has increased the demand for renewable energy. Notably, the production of biofuels from feedstock is gaining interest as a viable measure to reduce fossil fuels consumption. Nevertheless, it is crucial to identify the trade-offs between bioenergy crop cultivation and the environmental impact on land, water, and atmosphere.

Intensifying biofuel cultivation trigger effects associated with Land Use and Land-use-change, which are complex to assess. While hydrological models had been used to investigate the environmental impacts of land-use changes on water and soil quality, their quantitative assessment is often incomplete. Changes in land use and agricultural activities also contribute to …


Influence Of Upper-Tropospheric Troughs On Tropical Cyclone Intensity Change And Structure : Observational, Reanalysis, And Idealized Numerical Modeling Perspectives, Casey Peirano Jan 2019

Influence Of Upper-Tropospheric Troughs On Tropical Cyclone Intensity Change And Structure : Observational, Reanalysis, And Idealized Numerical Modeling Perspectives, Casey Peirano

Legacy Theses & Dissertations (2009 - 2024)

The interaction between tropical cyclones (TCs) and upper-tropospheric troughs is a


Predicting Spawning Habitat For Coho Salmon (Oncorhynchus Kisutch), Chinook Salmon (Oncorhynchus Tshawytscha), And Steelhead (Oncorhynchus Mykiss) Using Geospatially Constructed Stream Morphology From High-Resolution Lidar-Derived Digital Elevation Model And Field Survey Data In The Indian Creek Watershed, Mendocino County, California, Justin Patrick Bissell Mr. Jan 2019

Predicting Spawning Habitat For Coho Salmon (Oncorhynchus Kisutch), Chinook Salmon (Oncorhynchus Tshawytscha), And Steelhead (Oncorhynchus Mykiss) Using Geospatially Constructed Stream Morphology From High-Resolution Lidar-Derived Digital Elevation Model And Field Survey Data In The Indian Creek Watershed, Mendocino County, California, Justin Patrick Bissell Mr.

Cal Poly Humboldt theses and projects

Restoration of anadromous salmonid habitat is of primary importance to the economic, historical, and cultural geography of the Pacific Northwest. Derivation and use of geospatial habitat models as guides to pinpoint key areas where limited restoration funding can be cost-effectively employed is of great importance. To this purpose, 1 meter resolution lidar-derived Digital Elevation Model data was acquired for the Indian Creek and neighboring watersheds in Mendocino County, California, and used together with field-acquired geomorphic stream data to geospatially model stream widths, depths, and streambank morphology. These geospatial covariates were field-verified in selected locations and then used in conjunction with …


Ice Flow Impacts The Firn Structure Of Greenland's Percolation Zone, Rosemary C. Leone Jan 2019

Ice Flow Impacts The Firn Structure Of Greenland's Percolation Zone, Rosemary C. Leone

Graduate Student Theses, Dissertations, & Professional Papers

One dimensional simulations of firn evolution neglect horizontal transport as the firn column moves down slope during burial. This approach is justifiable near Greenland's ice divide, where ice flow is near vertical, but fidelity is lost in the percolation zone where horizontal ice flow advects the firn column through climate gradients. We simulate firn evolution processes under advection conditions using a transient, thermo-mechanically coupled model for firn densification and heat transfer with various schemes for meltwater penetration and refreezing. The simulations isolate processes in synthetic runs and investigate an ice core site and four transects of Greenland’s percolation zone. The …


The Correlation Between Sleep And Lifespan In Drosophila Melanogaster, Joshua Randall Lisse Jan 2019

The Correlation Between Sleep And Lifespan In Drosophila Melanogaster, Joshua Randall Lisse

Masters Theses

”Adequate sleep is associated with an individual’s health. Too little sleep is associated with many health problems, including cardiovascular disease, obesity, and a general increase in all-cause mortality. Yet the molecular changes that link poor sleep and changes in health are still not well understood. Individuals have a unique daily need for sleep, and deviations from the animal’s regular sleeping patterns can be indicative of, or result in, underlying changes in its health. Therefore, we hypothesize that changes in the sleep architecture in Drosophila melanogaster reflect changes in the fly’s health.

We determined sleep architecture in wild-type male flies over …


Investigation Of Pattern Formation In Marine Environments Through Mathematical Modeling And Analysis Of Remotely Sensed Data, Sofya Zaytseva Jan 2019

Investigation Of Pattern Formation In Marine Environments Through Mathematical Modeling And Analysis Of Remotely Sensed Data, Sofya Zaytseva

Dissertations, Theses, and Masters Projects

Pattern formation in ecological systems refers to a nonuniform distribution of animal and plant species across a landscape. Pattern formation can be observed in many aquatic and terrestrial systems and can provide important insights into their dynamics and ability to cope with environmental changes. In this dissertation, we focus on pattern formation in tidal marshes and oyster reefs, two important habitats that provide a number of essential ecosystem services. Both of these systems have also experienced dramatic losses, prompting much research to investigate their dynamics as and viable restoration and management strategies. The first part of this dissertation focuses on …


The Application Of Contemporary Numerical Methods To The Modeling, Analysis, And Uncertainty Quantification Of Glacier Dynamics, Jacob Zachary Downs Jan 2019

The Application Of Contemporary Numerical Methods To The Modeling, Analysis, And Uncertainty Quantification Of Glacier Dynamics, Jacob Zachary Downs

Graduate Student Theses, Dissertations, & Professional Papers

Warming temperatures have led to accelerating ice loss from the Greenland ice sheet, contributing to global sea level rise. Understanding the stability of the Greenland ice sheet to further warming is crucial to estimating rates of sea level rise over the next century. Estimating sea level rise is complicated by uncertainties in the physical mechanisms governing ice motion as well as uncertainties in the broader Arctic climate system of which the ice sheet is an integral part. In chapter 2, we focus on how surface melt water input to the ice sheet bed influences the rate of basal sliding, which …