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Bee Visitation To Crops And Other Flowers Planted As Bee Food, Michael Edward Wilson Dec 2011

Bee Visitation To Crops And Other Flowers Planted As Bee Food, Michael Edward Wilson

Masters Theses

Farms that require insect pollination and reside in diverse landscapes benefit from pollination by native bees. However, populations of native bees and honey bees are generally in decline and this threatens food production. Documentation of crop pollination as an ecosystem service is needed to identify potential impacts from declining bee populations. This study identifies communities of bees providing pollination and how they vary across different crops and environmental conditions. Managing landscapes to provide additional food sources for bees may improve the health of wild and managed bees. This study also evaluated the attractiveness of bees to selected species of plants …


Development Of An Environmental Monitoring System For Greenhouse Disease Management, Crystal Marie Kelly Dec 2011

Development Of An Environmental Monitoring System For Greenhouse Disease Management, Crystal Marie Kelly

Masters Theses

A commercial African violet (Saintpaulia ionantha) grower experiences yield loss due to a leaf spot disease known as Corynespora casssiicola. Spotted leaves make the plants unmarketable. Outbreaks of the disease are costly and difficult to prevent. Greenhouse monitoring systems currently available on the commercial market do not have sufficient spatial or temporal resolution to be able to correlate the environmental conditions of the greenhouse with disease outbreaks. A new system was designed specifically to monitor for disease favorable conditions. The system developed for this project consists of several sensor stations and a coordinator station. The coordinator station …


Processes Controlling The Composition Of First-Cycle Sediments Deposited In An Arid-Climate, With Implications For Provenance Reconstruction Studies, Aubrey Lynn Modi Dec 2011

Processes Controlling The Composition Of First-Cycle Sediments Deposited In An Arid-Climate, With Implications For Provenance Reconstruction Studies, Aubrey Lynn Modi

Masters Theses

Petrologic analysis of first-cycle clastic sediments derived from a single source in an arid environment provides a means to determine how well they resemble the petrology and geochemistry of their source. The Stepladder Mountains, located in the Mojave Desert of southeastern California, represents a well-controlled location (i.e., arid environment; single, known source; short transport distance) to examine how naturally formed sediments acquire their compositions. Compositional modifications associated with sediment production were resolved through direct examination of the weathered components (regolith, grus, and sediments). Sediment compositions strongly vary by grain size, indicating that, after the source itself, hydrodynamic sorting played the …


Automated Pollen Image Classification, Nicholas Quentin Haas Dec 2011

Automated Pollen Image Classification, Nicholas Quentin Haas

Masters Theses

This Master of Science thesis reviews previous research, proposes a method anddemonstrates proof-of-concept software for the automated matching of pollen grainimages to satisfy degree requirements at the University of Tennessee. An ideal imagesegmentation algorithm and shape representation data structure is selected, alongwith a multi-phase shape matching system. The system is shown to be invariantto synthetic image translation, rotation, and to a lesser extent global contrast andintensity changes. The proof-of-concept software is used to demonstrate how pollengrains can be matched to images of other pollen grains, stored in a database, thatshare similar features with up to a 75% accuracy rate.


Relationship Of Age Of Onset And Other Dimensions Of Trauma To Dissociation In An Adult Clinical Population, Amineh Abbas Dec 2011

Relationship Of Age Of Onset And Other Dimensions Of Trauma To Dissociation In An Adult Clinical Population, Amineh Abbas

Masters Theses

This study examined four dimensions of trauma and how they affected levels of dissociation in male and female adult outpatients. These dimensions are age of onset, multiple trauma, chronicity, and recency. Two hundred forty-five adult outpatients at the University of Tennessee Psychological Clinic were administered the Dissociative Experiences Scale (DES) and the Traumatic Experiences Checklist (TEC) as part of the routine intake procedure. Of those individuals, 177 patients reported trauma and were included in the final study sample. All four dimensions of trauma were found to be significantly correlated with dissociation. In addition, multiple trauma was found to be the …


U.S Inflight Icing Accidents And Incidents, 2006 To 2010., Philip Appiah-Kubi Dec 2011

U.S Inflight Icing Accidents And Incidents, 2006 To 2010., Philip Appiah-Kubi

Masters Theses

Through its recommendations, the National Transportation Safety Board (NTSB) has helped the Federal Aviation Administration (FAA) introduce regulations that have helped to curtail icing accidents1 (an occurrence associated with the operation of an aircraft where as a result of the operation of an aircraft, any person receives fatal or serious injury or any aircraft receives substantial damage) and incidents1 (an occurrence, other than an accident, associated with the operation of an aircraft that affects or could affect the safety of operations). However, "the only acceptable safety goal of zero accident," proposed by former Secretary of Transportation, Federico Fabian Pena, has …


Quasi-One-Dimensional Flow For Use In Real-Time Facility Simulations, Brett Matthew Boylston Dec 2011

Quasi-One-Dimensional Flow For Use In Real-Time Facility Simulations, Brett Matthew Boylston

Masters Theses

Simulations have been, and continue to play, an important role at the Arnold Engineering Development Center as an aid in control system development and operator training. These models were just simple lumped-parameter methods. Since their initial inception, over ten years ago, little work has been done to increase the fidelity of the models. The processing power of the computer hardware used by the simulations has increased dramatically during this time and this left an opening for improvements to the models adopted in the simulation. To fill this void a quasi-one-dimensional control volume has been developed to run in real-time. The …


Performance Specification For Tennessee Bridge Decks, Brian Ray Buchanan Dec 2011

Performance Specification For Tennessee Bridge Decks, Brian Ray Buchanan

Masters Theses

In today’s world of ever increasing demand on a weakening infrastructure, concentration is being firmly placed on increasing the sustainability of that infrastructure. Tennessee’s bridges and the concrete decks, on which the public travels, require a large part of the state’s infrastructure spending. Research has shown the current durability standards of Tennessee’s bridge decks could be significantly improved which would both increase service life and reduce maintenance costs of these structures. This research concentrates on greatly increasing the lifespan of these bridge decks, throughout the state, through an improved construction specification which will encourage the increased use of supplementary cementitious …


Potential Impacts Of Climate Change On Water Resources And Water Quality Of Norris Lake, Tennessee, Yong-Gil Choi Dec 2011

Potential Impacts Of Climate Change On Water Resources And Water Quality Of Norris Lake, Tennessee, Yong-Gil Choi

Masters Theses

This study assessed the potential impacts of climate change on hydrology, water resources operation, and water quality of the Norris Lake area in Tennessee. To project future climate conditions, the simulation outputs for 2030s, 2050s, and 2070s from six general circulation models (GCMs) were extracted under two Intergovernmental Panel on Climate Change (IPCC) greenhouse gases emissions scenarios (A2 and B1 for high and low emissions, respectively) to consider the range of uncertainty. The outputs of the six GCMs were weighted by considering their accuracy to simulate the climate conditions observed from 1961 to 1990 to suggest an ensemble average. A …


Short Distance Ground Wave Propagation Modeling In Irregular And Forested Environments, Zachary Michael Crane Dec 2011

Short Distance Ground Wave Propagation Modeling In Irregular And Forested Environments, Zachary Michael Crane

Masters Theses

A model for the phase of a ground wave propagating over irregular and forested terrain has been developed and tested for a transmission system operating at 3.315 MHz.

In this model, the time delay induced beyond that of the standard velocity of radio waves in air is modeled as a combination of 3 effects: the finite conductivity of the earth, the irregularity of the terrain over which the wave is propagating, and the forestation of the terrain.

The finite conductivity model is based on a small curvature formula developed by Van Der Pol and Bremmer. The terrain irregularity model models …


Spatial Epidemiology And Temporal Trends Of Heart Attack And Stroke In Middle Tennessee, Doreen Busingye Dec 2011

Spatial Epidemiology And Temporal Trends Of Heart Attack And Stroke In Middle Tennessee, Doreen Busingye

Masters Theses

Despite declines in mortality risks of myocardial infarction (MI) and stroke in the US since the 1960’s, the burdens of these conditions remain high. These conditions require emergency and specialized care and therefore quick transportation of patients to appropriate hospitals is critical. Geographic disparities in MI and stroke burdens have been consistently reported in the US with the south-east having the highest risks. Most studies of geographic disparities have been performed at county or higher geographic units. Therefore, spatial patterns at neighborhood levels are unclear. Moreover, it’s important to investigate disparities at neighborhood levels to better understand neighborhood health needs. …


Residential Attic Ventilation In A Hot And Humid Climate: Effects Of Increased Ventilation On Thermal Performance And Moisture Control, Stanley Arthur Atherton Dec 2011

Residential Attic Ventilation In A Hot And Humid Climate: Effects Of Increased Ventilation On Thermal Performance And Moisture Control, Stanley Arthur Atherton

Masters Theses

The reality of the effect of natural ventilation in a residential attic cavity has been the topic of many debates and scholarly reports since the 1930’s. The purpose of ventilating an attic cavity is to prevent collection of condensate on the structural surfaces, and to create a thermal buffer between the conditioned space and the ambient air. The current standards are not specific to climate zone, despite the fact that each climate zone may require ventilation for very different reasons.

To address the issue of ventilation effects in a hot and humid climate, a Natural Exposure Testing facility was constructed …


Consequences Of Gene Flow And Transgene Introgression In Hybrids Between Transgenic Brassica Napus And Its Weedy Wild Relative Brassica Rapa, Reginald Jason Millwood Dec 2011

Consequences Of Gene Flow And Transgene Introgression In Hybrids Between Transgenic Brassica Napus And Its Weedy Wild Relative Brassica Rapa, Reginald Jason Millwood

Masters Theses

The adventitious presence of transgenes and their potential impact on the environment has been a topic of concern for many years. To address these concerns the following chapters discuss past and current research of gene flow and introgression, methods for transgene detection and monitoring, and the results from field-level experiments using artificially introgressed advanced generation hybrids. The field studies were designed to be a worst-case scenario where hybrids were produced by hand-crossing transgenic Brassica napus (AACC, 2n = 38) and its weedy wild relative Brassica rapa (AA, 2n = 20). B. napus was transgenic for the green fluorescent protein [m-GFP-5 …


Integrated Strategies For Controlling Warm-Season Turfgrass Weeds, Matthew Thomas Elmore Dec 2011

Integrated Strategies For Controlling Warm-Season Turfgrass Weeds, Matthew Thomas Elmore

Masters Theses

Herbicidal inhibitors of 4-hydroxyphenylpyruvate dioxygenase (HPPD) such as mesotrione, topramezone and tembotrione were evaluated in greenhouse experiments for activity against bermudagrass. While topramezone and tembotrione exhibited greater activity than mesotrione, none of these herbicides provided acceptable bermudagrass control. These herbicides reduced leaf tissue chlorophyll and carotenoid pigment concentrations in bermudagrass. Changes in turfgrass pigmentation were quantified using HPLC analogy as well as evaluations of visual bleaching and measurements of chlorophyll fluorescence yield (Fv/Fm). Results indicated that these more expeditious methods of evaluating HPPD-inhibiting herbicide activity (visual evaluations and Fv/Fm) cannot be used …


Factors Related To Nest Survival And Over-Winter Survival Of A Northern Bobwhite (Colinus Virginianus) Population In Southwest Florida, Steven Kenneth Brinkley Dec 2011

Factors Related To Nest Survival And Over-Winter Survival Of A Northern Bobwhite (Colinus Virginianus) Population In Southwest Florida, Steven Kenneth Brinkley

Masters Theses

The northern bobwhite (Colinus virginianus) is a gallinaceous upland game bird dependent on early successional grassland habitat for reproduction and survival. Bobwhite populations have been declining range-wide for nearly a half century. The habitat of Babcock-Webb Wildlife Management Area (BWWMA) in southwest Florida is mostly virgin, early successional grassland and pine flatwoods. Although BWWMA is located in the far southern end of the bobwhite range, the area is a popular public land for bobwhite hunting. The BWWMA bobwhite population has declined evidenced by a dramatic decrease in harvest over the last 20 years. The two objectives of my …


An Evaluation Of Population Estimators And Forage Availability And Nutritional Quality For White-Tailed Deer In Tennessee, Jared Tyler Beaver Dec 2011

An Evaluation Of Population Estimators And Forage Availability And Nutritional Quality For White-Tailed Deer In Tennessee, Jared Tyler Beaver

Masters Theses

Given the white-tailed deer’s (Odocoileus virginianus; deer) popularity and potentially negative impact on forested systems; Arnold Air Force Base (AAFB) in Tullahoma, Tennessee, USA has made minimizing negative deer impacts on biodiversity a priority. To address these management issues, I initiated a study on AAFB to investigate deer survey techniques and the effects of deer density on forage availability across vegetative communities.

Current use of infrared-triggered cameras (camera) for estimating deer populations does not provide a measure of precision critical for density estimation. I conducted a camera survey for deer in Wildlife Management Area (WMA) Units 1 and …


Communicating Via Knoxblab, Roger Kevin Gray Dec 2011

Communicating Via Knoxblab, Roger Kevin Gray

Masters Theses

This study is a Uses and Gratifications based look at motivations surrounding long-term participation in an internet discussion forum and perceived effects of this participation on users’ social lives. Members of the Knoxville, TN based web forum “Knoxblab” were interviewed for the study. Participants indicated that the forum is a tool by which social ties are maintained and developed, and they indicated that membership in the forum community is perceived as having positive effects on social activity. Consistent with traditional Uses and Gratifications Theory, results suggest that participants are motivated by reasons related to information sharing and entertainment, though web …


Prognostics-Based Two-Operator Competition For Maintenance And Service Part Logistics, Faranak Fathi Aghdam Dec 2011

Prognostics-Based Two-Operator Competition For Maintenance And Service Part Logistics, Faranak Fathi Aghdam

Masters Theses

Prognostics and timely maintenance of components are critical to the continuing operation of a system. By implementing prognostics, it is possible for the operator to maintain the system in the right place at the right time. However, the complexity in the real world makes near-zero downtime difficult to achieve partly because of a possible shortage of required service parts. This is realistic and quite important in maintenance practice. To coordinate with a prognostics-based maintenance schedule, the operator must decide when to order service parts and how to compete with other operators who also need the same parts. This research addresses …


The Social Memory Of Upper Hampton Farm: An Organizational And Ceramic Study Of 40rh41, Jessica Nicole Dalton-Carriger Dec 2011

The Social Memory Of Upper Hampton Farm: An Organizational And Ceramic Study Of 40rh41, Jessica Nicole Dalton-Carriger

Masters Theses

The Upper Hampton Farm site (40RH41) is located in the Watts Bar Reservoir in East Tennessee. The site was excavated under the Works Progress Administration between 1940 and 1941 and the collections are currently curated in the Frank H. McClung Museum in Knoxville, Tennessee. Based on the excavation notes and artifact analysis, a complex culture history emerged at Upper Hampton Farm, which culminated in a land modification project to conceal a Late Woodland Hamilton burial mound by a Late Mississippian Period population. The goal of this thesis is to examine and explain the complex archaeological record of Upper Hampton Farm …


Mediating Justice: Toward A Critical-Reflexive Sociology, George Christopher Gondo Dec 2011

Mediating Justice: Toward A Critical-Reflexive Sociology, George Christopher Gondo

Masters Theses

Today, an increasing number of sociologists incorporate the theme of social justice within their work and strive to contribute to efforts to improve existing social conditions. In their view, sociological work that actively engages in issues related to social justice exemplifies ‘the promise’ of sociology and represents a means of refocusing and reinvigorating the discipline at a time of perceived crisis. Yet, a growing body of evidence questions whether previous efforts to use sociology as a mechanism of improving social conditions have been successful. In this thesis, I rely on the works of Alvin W. Gouldner to examine the relationship …


Particle Shielding For Human Spaceflight: Electrostatic Potential Effects On The Störmer Magnetic Dipole Exclusion Region, Benjamin Alan Klamm Dec 2011

Particle Shielding For Human Spaceflight: Electrostatic Potential Effects On The Störmer Magnetic Dipole Exclusion Region, Benjamin Alan Klamm

Masters Theses

A basic hybrid radiation shield concept, consisting of both a monopole positive electrostatic potential barrier and a current-carrying superconducting solenoid, was predicted to provide a more effective method of shielding a habitable torus region than a solenoid acting alone. A randomized position and velocity vector simulation of equal-energy iron ions using a Lagrangian reference frame was performed on the exact magnetic field integral for the solenoid and a discrete summation electrostatic field for a toroidal monopole array approximating a potential surface. Each particle is injected at a specific energy (100, 150 MeV and 1 GeV). Two cases were evaluated at …


Capture-Recapture Of White-Tailed Deer Using Dna Sampling From Fecal Pellet-Groups, Matthew James Goode Dec 2011

Capture-Recapture Of White-Tailed Deer Using Dna Sampling From Fecal Pellet-Groups, Matthew James Goode

Masters Theses

Reliable density estimates of game and keystone species such as white-tailed deer (Odocoileus virginianus) are desirable to set proper management strategies and for evaluating those strategies over time. However, traditional methods for estimating white-tailed deer density have been inhibited by behavior, densely forested areas that can hamper observation (detection), and invalid techniques of estimating effective trapping area. We wanted to evaluate a noninvasive method of mark-recapture estimation using DNA extracted from fecal pellets as the individual marker and for gender determination, coupled with a spatial detection function to estimate density (Spatially Explicit Capture-Recapture, SECR). We collected pellet groups …


Power Management For Gpu-Cpu Heterogeneous Systems, Xue Li Dec 2011

Power Management For Gpu-Cpu Heterogeneous Systems, Xue Li

Masters Theses

In recent years, GPU-CPU heterogeneous architectures have been increasingly adopted in high performance computing, because of their capabilities of providing high computational throughput. However, current research focuses mainly on the performance aspects of GPU-CPU architectures, while improving the energy efficiency of such systems receives much less attention. There are few existing efforts that try to lower the energy consumption of GPU-CPU architectures, but they address either GPU or CPU in an isolated manner and thus cannot achieve maximized energy savings. In this paper, we propose GreenGPU, a holistic energy management framework for GPU-CPU heterogeneous architectures. Our solution features a two-tier …


Education & Crime: A Study In Student Perceptions Of Culpability, Larry Curtis Long Dec 2011

Education & Crime: A Study In Student Perceptions Of Culpability, Larry Curtis Long

Masters Theses

Criminological research has long been concerned with how stereotypes of offender race and gender affect perceived culpability and policy formation. Using data collected from a college student population that were administered six vignettes written in the form of police blotters that depicted different crimes being committed by offenders with differing educational characteristics, this study seeks to identify whether or not an offender’s educational characteristics affect their perceived culpability. Although the data indicates that offender’s are seen as culpable regardless of their educational characteristics, it is evident that some degree or sociopathy is assessed to offender’s that are seen as educated …


Comparative Study On Posture And Its Influences On Horizontal Ground Reaction Forces Generated By Muscles: Implications For Crouch Gait, Hoa Xuan Hoang Dec 2011

Comparative Study On Posture And Its Influences On Horizontal Ground Reaction Forces Generated By Muscles: Implications For Crouch Gait, Hoa Xuan Hoang

Masters Theses

Crouch gait decreases walking efficiency due to the increased knee and hip flexion during the stance phase of gait. Crouch gait is generally considered to be disadvantageous for patients with cerebral palsy; however, a crouched posture may afford biomechanical advantages that lead some patients to adopt a crouch gait.

To investigate one possible advantage of crouch gait, a musculoskeletal model created in OpenSim was placed in 15 different postures from upright to severe crouch during initial, middle, and final stance of the gait cycle. A series of optimizations were performed for each posture to maximize ground reaction forces for the …


Application Of Liquid Chromatography-Tandem Mass Spectrometry Techniques To The Study Of Two Biological Systems, Mary E. Eisenhauer Dec 2011

Application Of Liquid Chromatography-Tandem Mass Spectrometry Techniques To The Study Of Two Biological Systems, Mary E. Eisenhauer

Masters Theses

Quorum sensing is a type of bacterial cell-cell communication that uses diffusible signaling molecules to allow the regulation of gene expression based on cell density. The two types of signaling molecules discussed here are autoinducer-2 (AI-2) and a class of signaling molecules of the N-acylhomoserine lactone type (AHL) also known as autoinducer-1 (AI-1). The biosynthesis of both of these molecules has origins in a metabolic pathway. Although undisputed in some cases, the role of AI-2 and AHLs in bacterial systems has come into question. Here, the functionalities of these molecules were investigated by utilizing isotope-labeled versions of both AI-2 …


Influence Of Timing Of Prescribed Burn On Native-Warm Season Grass Forage Quality In Tennessee, Amanda L. Mathenia Dec 2011

Influence Of Timing Of Prescribed Burn On Native-Warm Season Grass Forage Quality In Tennessee, Amanda L. Mathenia

Masters Theses

Native warm-season grass stands have the prospective to provide nutritious summer forage in grazing systems. The study examined the influence of timing of prescribed burn on native warm-season grass stands in Tennessee. The purpose of the study was to determine the nutritional quality of forage as it relates to the timing of prescribed burns on native warm-season grass stands in Tennessee. The prescribed burns were conducted in March, April, May, and September. Forage samples were collected at Ames Plantation, West Tennessee Research and Education Center, Bridgestone/Firestone Wildlife Management Area, and Yuchi Wildlife Management Area. These samples were then analyzed for …


Aeolian Simulations: A Comparison Of Numerical And Experimental Results, With Projections For Titan., Oscar Lee Mathews Dec 2011

Aeolian Simulations: A Comparison Of Numerical And Experimental Results, With Projections For Titan., Oscar Lee Mathews

Masters Theses

Aeolian processes are major determinants of geomorphology on bodies in the Solar System possessing an atmosphere-surface interface and transportable sediment, including Earth, Mars, Venus, and Titan. Substantial efforts have been made over the last few decades to understand these processes using specialized wind tunnels, field studies, and, more recently, numerical simulations. This thesis describes a model of aeolian sediment transport using computational fluid dynamics (CFD), and compares the results with those obtained in the Martian Surface Wind Tunnel (MARSWIT) testing conducted in the Planetary Aeolian Laboratory at NASA Ames Research Center. The ultimate goal of the thesis was to develop …


Late Pleistocene And Holocene Hydroclimate Change In The Southeastern United States: Sedimentary, Pedogenic, And Stable Carbon Isotope Evidence In Tennessee River Floodplain Paleosols, James Joseph Kocis Dec 2011

Late Pleistocene And Holocene Hydroclimate Change In The Southeastern United States: Sedimentary, Pedogenic, And Stable Carbon Isotope Evidence In Tennessee River Floodplain Paleosols, James Joseph Kocis

Masters Theses

In order to understand hydroclimate variability of future climate change, it is important to know the timing and range of natural climate change in the past. The Southeastern United States (SE) is situated along the poleward extent of projected subtropical drying, where the expression of past hydrological balances remains unclear. The lack of high-resolution paleohydroclimate records in the SE forces climate modelers to base interpretations on better-understood regions of North America. The SE likely experienced significant changes in precipitation regimes resulting from its position at the convergence of several oceanic and continental air masses. To reconstruct precipitation variability, this study …


Correlating Suspended Sediment And Biological Metrics In East Tennessee Streams, Jeremy Robert Mefford Dec 2011

Correlating Suspended Sediment And Biological Metrics In East Tennessee Streams, Jeremy Robert Mefford

Masters Theses

Excessive suspended sediment is a major cause of pollution in US streams, as reported by the USEPA. Also known as siltation, having excessive sediment in a stream harms the biology of a stream through directly affecting living organisms, but also through harming natural habitats. Too much excessive sediment leads to a stream being declared impaired. Testing for suspended sediment levels is difficult and time consuming, so indirect methods of testing for total suspended solids (TSS) are desirable. While turbidity has been an oft used TSS surrogate in the past, this study takes the next step of looking at potential relationships …