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Landscape Change In The South Prong Alafia River Basin, Kimberly Sarah Koenig Dec 2006

Landscape Change In The South Prong Alafia River Basin, Kimberly Sarah Koenig

Graduate Theses and Dissertations

West-central Florida has supplied much of the national and global demand for phosphate for over 100 years. The two main tributaries of the Alafia River, the North and South Prongs, have been extensively modified by the strip mining, benefaction, and chemical processing activities associated with the phosphate mining industry. Using aerial photos, an analysis of landscape change in the South Prong Alafia River drainage basin (357.4 km2) between 1940, 1970, and 2004 was conducted. A modified Florida Land Use, Land Cover, and Forms Classification System code (FLUCCS) was used to classify and measure change through the study period. Change ...


Measuring Social Stressors In Organizations: The Development Of The Interpersonal Conflict In Organizations Scale (Icos), Valentina Bruk Lee Aug 2006

Measuring Social Stressors In Organizations: The Development Of The Interpersonal Conflict In Organizations Scale (Icos), Valentina Bruk Lee

Graduate Theses and Dissertations

Interpersonal conflict in organizations has been recognized as a leading social stressor across occupations with detrimental effects on employee well-being and organizational outcomes. However, reliable and valid measures of conflict are scarce and even the most widely used scales are limited by weaknesses in construct definition. In order to address the need for an improved measurement tool, the 63-item Interpersonal Conflict in Organizations Scale (ICOS) was developed. The ICOS was based on a comprehensive conceptualization of conflict that defines the construct on the basis of three definitional components: disagreement, interference, and negative emotion (Barki & Hartwick, 2004). In addition, the ICOS ...


Hydrogen Isotopic Ratios Of Algal And Terrestrial Organic Matter In Lake Tulane, Florida: From A Modern Calibration To The Reconstruction Of Paleoclimatic And Paleohydrologic Conditions, Eric Charles Cross Jul 2006

Hydrogen Isotopic Ratios Of Algal And Terrestrial Organic Matter In Lake Tulane, Florida: From A Modern Calibration To The Reconstruction Of Paleoclimatic And Paleohydrologic Conditions, Eric Charles Cross

Graduate Theses and Dissertations

Recent sedimentary records have indicated that climate in low latitude, continental environments have varied significantly throughout the mid to late Holocene. In subtropical North America, major climatic phenomena such as the migration of the Intertropical Convergence Zone (ITCZ) and the Bermuda High have been shown to play a major role in this variability. Specifically, the northward migration of the ITCZ and the eastward position of the Bermuda High during summer months leads to warmer and wetter conditions over subtropical North America, and vice versa. A quantitative approach to understanding hydrologic dynamics (i.e. atmospheric circulation patterns, relative humidity) associated with ...


Development Of An End-Effector Sensory Suite For A Rehabilitation Robot, Stephanie A. Stiber Jul 2006

Development Of An End-Effector Sensory Suite For A Rehabilitation Robot, Stephanie A. Stiber

Graduate Theses and Dissertations

This research presents an approach in assisting the control and operation of a rehabilitation robot manipulator to execute simple grasping tasks for persons with severe disabilities. It outlines the development of an end-effector sensory suite that includes the BarrettHand end-effector, laser range finder, and a low cost camera.

The approach taken in this research differs greatly from the currently available rehabilitation robot arms in that it requires minimal user instruction, it is easy to operate and more effective for persons severely disabled. A thorough study of the currently available systems; Manus, Raptor and Kares II arm, is also presented.

In ...


Geophysical Investigations And Groundwater Modeling Of The Hydrologic Conditions At Masaya Caldera, Nicaragua, Richard Eric Macneil Jul 2006

Geophysical Investigations And Groundwater Modeling Of The Hydrologic Conditions At Masaya Caldera, Nicaragua, Richard Eric Macneil

Graduate Theses and Dissertations

Masaya volcano, Nicaragua, has been the site of tremendous Plinian basaltic eruptions. Two eruptions ~6,500 and 2,250 BP formed the 6 kilometer (km) x 11 km, northwest trending Masaya caldera. The present day active Santiago Crater within the caldera is the site of persistent volcano degassing and occasional phreatic explosions. While the mechanism responsible for these phreatic explosions is unclear, one possible explanation is the interaction of groundwater with the shallow magma chamber beneath Masaya. This interaction with meteoric water is supported by the substantial steam discharge from the vent, which is significantly larger than other similar volcanoes ...


The Reaction To Economic Globalization In Latin America: A Case Study Of Argentina, Lisa A. Warner Jul 2006

The Reaction To Economic Globalization In Latin America: A Case Study Of Argentina, Lisa A. Warner

Graduate Theses and Dissertations

Since Washington Consensus policies became predominant in the 1980s, two sides of the economic globalization debate have developed: advocates claim that trade liberalization, deregulation, privatization and reduced state spending increase growth and therefore reduce poverty, while critics claim that levels of poverty and income disparity have worsened at the same time that social welfare and education programs have suffered budget cuts. Over the past decade, as many Latin Americans have failed to see promised results to alleviate poverty stemming from the "lost decade" of the 1980s (and beyond), they have elected "leftist" presidents that campaigned on anti-economic globalization (or anti-neoliberal ...


A Mechanized Horseback Riding Simulator As An Aid To Physical Therapy, Jennifer Lott Jul 2006

A Mechanized Horseback Riding Simulator As An Aid To Physical Therapy, Jennifer Lott

Graduate Theses and Dissertations

Equine-assisted therapy is a nontraditional form of physical therapy that involves riding horses as a form of rehabilitation. Limited access to these riding programs justifies a need to develop a horseback riding simulator capable of simulating the gaits, bend, and collection of the horse. Research involving the development of horseback riding simulators is limited, but the available research does show promising results in the ability to aid in physical therapy.

A two-dimensional model and simulation was developed using MATLAB. Using the results from the simulation, a horseback riding simulator was designed, fabricated and tested. The physical simulator was capable of ...


Knowledge-Based Video Compression For Robots And Sensor Networks, Chris Williams Williams Jul 2006

Knowledge-Based Video Compression For Robots And Sensor Networks, Chris Williams Williams

Graduate Theses and Dissertations

Robot and sensor networks are needed for safety, security, and rescue applicationssuch as port security and reconnaissance during a disaster. These applications rely on realtimetransmission of images, which generally saturate the available wireless networkinfrastructure. Knowledge-based Compression is a strategy for reducing the video frametransmission rate between robots or sensors and remote operators. Because images mayneed to be archived as evidence and/or distributed to multiple applications with differentpost processing needs, lossy compression schemes, such as MPEG, H.26x, etc., are notacceptable. This work proposes a lossless video server system consisting of three classesof filters (redundancy, task, and priority) which use ...


Study Of Upward-Facing Spray Cooling With Water At Atmospheric Pressure, Alberto D. Sato Jul 2006

Study Of Upward-Facing Spray Cooling With Water At Atmospheric Pressure, Alberto D. Sato

Graduate Theses and Dissertations

Spray cooling is a high heat removal technique which has been used widely in many industries, especially metallurgical, where the control of the temperatures of metals is an important factor to obtain the desired microstructure; and also in microelectronics where is very important to obtain high heat fluxes at relatively low surface temperatures. In this study, an open loop spray cooling system has been fabricated to provide an upward-facing spray over a 12 mm diameter test surface. A full cone spray nozzle was used to deliver deionized water to the test surface at five pressures (10, 15, 20, 25 and ...


Mining Medical Data In A Clinical Environment, Tim V. Ivanovskiy Jul 2006

Mining Medical Data In A Clinical Environment, Tim V. Ivanovskiy

Graduate Theses and Dissertations

The availability of new treatments for a disease depends on the success of clinical trials. In order for a clinical trial to be successful and approved, medical researchers must first recruit patients with a specific set of conditions in order to test the effectiveness of the proposed treatment. In the past, the accrual process was tedious and time-consuming. Since accruals rely heavily on the ability of physicians and their staff to be familiar with the protocol eligibility criteria, candidates tend to be missed. This can result and has resulted in unsuccessful trials.A recent project at the University of South ...


Establishing A Functional Analysis Protocol For Examining Behavioral Deficits Using Social Withdrawal As An Exemplar, Melissa Penaranda Walters Jun 2006

Establishing A Functional Analysis Protocol For Examining Behavioral Deficits Using Social Withdrawal As An Exemplar, Melissa Penaranda Walters

Graduate Theses and Dissertations

The purpose of this study was to establish a functional analysis protocol for examining behavioral deficits, using social withdrawal as an exemplar. A review of the Journal of Applied Behavior Analysis over the past 10 years found that although the current behavior analytic literature contains extensive studies that functionally analyze behavioral excesses, there is a limited amount of studies that analyze deficits. The rationale behind this study was the notion that although behavioral deficits are rarely studied, the fact that the participant is capable of the behavior yet fails to engage in it leads to the idea that certain events ...


The Acquisition Of Functional Sign Language By Non-Hearing Impaired Infants, Kerri Haley-Garrett Jun 2006

The Acquisition Of Functional Sign Language By Non-Hearing Impaired Infants, Kerri Haley-Garrett

Graduate Theses and Dissertations

Research shows that young children, typically developing with no developmental delays, hearing impairments or visual impairments, can acquire sign language to communicate their wants or needs prior to their ability to communicate through spoken language. However, much of the research reviewed focused on whether it was normative for young children to use signs or symbolic gestures to represent objects, make requests, or to express other wants or needs. In addition, many of the studies reviewed lacked scientific rigor and were primarily anecdotal in that much of the data relied on parent reports of his/her child's production of signs ...


Effect Of Tricalcium Silicate Content On Expansion In Internal Sulfate Attack, Troy T. Whitfield Jun 2006

Effect Of Tricalcium Silicate Content On Expansion In Internal Sulfate Attack, Troy T. Whitfield

Graduate Theses and Dissertations

The purpose of this study was to determine the cementitious parameters and placement temperature that impact internal sulfate attack in concrete. Concrete structures make up a large percentage of the infrastructure and multifamily housing. Durability is very important. Cements can be formulated to reduce the impact of external environmental exposure such as high salinity from marine environments or high sulfate levels from soils or surface waters. Concrete is also subject to internal attack such as alkali aggregate reaction, (AAR), and delayed ettringite formation, (DEF). This study focused on some of the cement chemistry issues that determine susceptibility of cement to ...


What Is The Effect Of Retrieval Practice On Competing Associates In Cued-Recall?, Umit Akirmak Jun 2006

What Is The Effect Of Retrieval Practice On Competing Associates In Cued-Recall?, Umit Akirmak

Graduate Theses and Dissertations

There have been many theories on why we forget. One of the recent approaches to this phenomenon is retrieval induced forgetting (RIF). The present study investigated RIF and different kinds of disruptions and their effects by using extra-list cued recall task. Some participants studied two additional word lists after the target list and some participants studied and were tested from these interpolated lists before their final recall of target list. Relatedness of the interfering lists was also manipulated. There were two control groups that either got an immediate test or got a math task before memory test. The particular interest ...


Continuous Time Disaggregation In Hierarchical Production Planning, Rami Salhab Al-Tamimi Jun 2006

Continuous Time Disaggregation In Hierarchical Production Planning, Rami Salhab Al-Tamimi

Graduate Theses and Dissertations

One of the objectives of disaggregation in hierarchical production planning is to minimize the setup costs incurred when changing production from one family to another. In this research, the setup costs are reduced by determining a production schedule that minimizes the number of setups during the planning horizon. Previous solutions to the disaggregation problem have considered discrete-time, and more recently continuous-time formulations. This research extends the continuous time disaggregation approach by incorporating production schedules allowing backorder. A mathematical formulation and a solution algorithm are presented and the computational complexity and convergence properties of the algorithm are discussed. Experimental results, using ...


Polynomial Quandle Cocycles, Their Knot Invariants And Applications, Kheira Ameur Jun 2006

Polynomial Quandle Cocycles, Their Knot Invariants And Applications, Kheira Ameur

Graduate Theses and Dissertations

A quandle is a set with a binary operation that satisfies three axioms that corresponds to the three Reidemeister moves on knot diagrams. Homology and cohomology theories of quandles were introduced in 1999 by Carter, Jelsovsky,Kamada, Langford, and Saito as a modification of the rack (co)homology theory defined by Fenn, Rourke, and Sanderson. Cocycles of the quandle (co)homology, along with quandle colorings of knot diagrams, were used to define a new invariant called the quandle cocycle invariants, defined in a state-sum form. This invariant is constructed using a finite quandle and a cocyle, and it has the ...


Electromagnetic Characterization Of Miniature Antennas For Portable Devices, Diana P. Aristizabal Jun 2006

Electromagnetic Characterization Of Miniature Antennas For Portable Devices, Diana P. Aristizabal

Graduate Theses and Dissertations

Advances in technology have placed a great emphasis on the design of broadband antennas as well as antenna miniaturization to cope with the demands of making electronic and handheld communication devices smaller and more efficient. In this thesis, the design and fabrication of a frequency independent antenna and a narrow-band planar microstrip Balun are presented. An analysis of frequency selective surfaces is also introduced in order to demonstrate their capability to miniaturize antenna thickness. Lastly, s-parameters measurements and efficiency characterization are performed to determine the radiation properties of surface mount chip inductors in order to determine the feasibility of using ...


Study Of Laplace And Related Probability Distributions And Their Applications, Gokarna Raj Aryal Jun 2006

Study Of Laplace And Related Probability Distributions And Their Applications, Gokarna Raj Aryal

Graduate Theses and Dissertations

The aim of the present study is to investigate a probability distribution that can be derived from the laplace probability distribution and can be used to model various real world problems. In the last few decades, there has been a growing interest in the construction of flexible parametric classes of probability distributions. Various forms of the skewed and kurtotic distributions have appeared in the literature for data analysis and modeling. In particular, various forms of the skew laplace distribution have been introduced and applied in several areas including medical science, environmental science, communications, economics, engineering and finance, among others. In ...


Adolescent Alcohol Use And Educational Outcomes, Wesley A. Austin Jun 2006

Adolescent Alcohol Use And Educational Outcomes, Wesley A. Austin

Graduate Theses and Dissertations

There is some controversy over whether adolescent alcohol use has deleterious causal effects on educational outcomes. In particular, does drinking reduce academic performance and school enrollment rates and increase truancy, or does the observed negative correlation between drinking and educational outcomes merely reflect common unobservable factors? This dissertation sheds further light on the issue by estimating the causal impacts of alcohol use on various educational outcomes. Specifically, an instrumental variables model is estimated to study the effects of several drinking measures on grades, school enrollment and absenteeism.


Design And Synthesis Of Core Structural Intermediates For Novel Hiv-1 Protease Inhibitors & Synthesis, Biological Activity And Molecular Modeling Of Novel 20s Proteasome Inhibitors, Kiran Kumar Venkata Raja Avancha Jun 2006

Design And Synthesis Of Core Structural Intermediates For Novel Hiv-1 Protease Inhibitors & Synthesis, Biological Activity And Molecular Modeling Of Novel 20s Proteasome Inhibitors, Kiran Kumar Venkata Raja Avancha

Graduate Theses and Dissertations

HIV-1 protease binds to its peptide/protein substrates in extended conformations. Therefore protease inhibitors that are constrained to form extended conformations are likely to produce very active protease inhibitors. This is because they are pre-organized to form favorable interactions with the enzyme environment immediately surrounding the active site. With this hypothesis in mind, we designed a family of structurally related molecules, which contain dipeptide analogs constrained to adopt the extended conformation. Core structural intermediates that are required for the total synthesis of the novel class of HIV-1 protease inhibitors are outlined in Chapter One. Chapter Two discusses the enantioselective synthesis ...


Implications Of Sleep Disorders Symptoms On School Behavior, Academics, And Quality Of Life, Erin Elizabeth Ax Jun 2006

Implications Of Sleep Disorders Symptoms On School Behavior, Academics, And Quality Of Life, Erin Elizabeth Ax

Graduate Theses and Dissertations

Pediatric sleep problems are among the most common yet significant pediatric health issues faced by families. Sleep problems can impact social-emotional and academic functioning of schoolchildren. Once identified, pediatric sleep problems and disorders are treatable with effective and rapid behavioral and medical interventions. The purpose of the current study was to determine the prevalence rates of symptoms of sleep disorders in a diverse school-based sample as well as the relationship between symptoms of sleep disorders and school behavior, academic achievement, and quality of life. The present study examined the relationship between the independent variables of No Sleep Disorders symptoms and ...


Comparing The Effects Of The Exotic Cactus-Feeding Moth, Cactoblastis Cactorum (Berg) (Lepidoptera: Pyralidae) And A Native Cactus-Feeding Moth, Melitara Prodenialis (Walker) (Lepidoptera: Pyralidae) On Two Species Of Florida Opuntia, Amanda J. Baker Jun 2006

Comparing The Effects Of The Exotic Cactus-Feeding Moth, Cactoblastis Cactorum (Berg) (Lepidoptera: Pyralidae) And A Native Cactus-Feeding Moth, Melitara Prodenialis (Walker) (Lepidoptera: Pyralidae) On Two Species Of Florida Opuntia, Amanda J. Baker

Graduate Theses and Dissertations

Exotic species are a great concern because of the possibility of negative effects once they become established. The exotic cactus moth, Cactoblastis cactorum has a reputation for being detrimental to Opuntia populations throughout Florida and the southeastern United States. Multiple projects are currently underway to attempt to contain and eradicate this species before it can migrate to the Opuntia-rich desert southwest and the agricultural Opuntia fields in the Mexican highlands. These projects have been undertaken without previous studies to determine what negative effects, if any, the moth is having on the common native Opuntia species. This is understandable; since it ...


Community Of Practice As Community Of Learners: How Foreign Language Teachers Understand Professional And Language Identities, Ruth Ban Jun 2006

Community Of Practice As Community Of Learners: How Foreign Language Teachers Understand Professional And Language Identities, Ruth Ban

Graduate Theses and Dissertations

This study seeks to understand the transmogrification of four Mexican foreign language teachers as they participate in a teaching exchange in American schools throughout the United States. Previous research into development of competent membership in given communities of practice points to the need for mutual engagement with other community members, an understanding of the community activity, and a shared repertoire among community members. Framed within an activity theory perspective, the present study examined how the teachers's socio-historical background, cultural tools and artifacts, along with other pedagogical activities, community rules, and division of labor mediated the teachers' understanding of their ...


Understanding Activity Engagement And Time Use Patterns In A Developing Country Context, Amlan Banerjee Jun 2006

Understanding Activity Engagement And Time Use Patterns In A Developing Country Context, Amlan Banerjee

Graduate Theses and Dissertations

Flourishing economy, rapid industrialization and increasing trend of motorization have been shaping societies in the developing countries like India in an unprecedented manner.Infrastructure backlog amid such rapid growth in all imaginable directions has heavily exacerbated the urban transport crisis in these countries by alarming increase in vehicular travel demand, road fatalities, and environmental pollution. To address urban transport challenges, the necessary development and implementation of effective transport planning and policies have generally lagged in the developing countries compared to that seen in the developed countries due to several constraints including resource constraints, knowledge constraints, institutional constraints and so on ...


Teaching Philosophy And Practices Among Chemistry Faculty Attending The Mid Project Workshops: Implications For Reform In Chemistry, Beverly Dee Barker Jun 2006

Teaching Philosophy And Practices Among Chemistry Faculty Attending The Mid Project Workshops: Implications For Reform In Chemistry, Beverly Dee Barker

Graduate Theses and Dissertations

Over the past decade over 600M in funding has been devoted to bringing about reform in science education, but little is known about who is implementing reform, the extent of reform implementation and how educational contexts differentially impact reform innovations. This dissertation explores the results of the Multi-Initiative Dissemination Project (MID Project), a national curriculum reform program that was designed to propagate reform pedagogy among undergraduate chemistry faculty in faculty development workshops. We analyzed data from surveys, in-class observations and faculty interviews to explore the relationships between the participant faculty demographic features and their pedagogy and teaching philosophy before and ...


Mathematical Model Of Arsenic Adsorption In A Modified Zeolite / Microfiltration System, Miles B. Beamguard Jun 2006

Mathematical Model Of Arsenic Adsorption In A Modified Zeolite / Microfiltration System, Miles B. Beamguard

Graduate Theses and Dissertations

Carcinogenic health concerns over arsenic in drinking water caused the USEPA to reduce the maximum contaminant level (MCL) from 50 to 10 ppb, effective on January 23, 2006. This has forced many smaller utilities into expensive treatment or discontinuation of water distribution. Researchers throughout the world are working to develop an inexpensive method for arsenic removal to meet this MCL. Aluminum silicates, or zeolites, are naturally occurring ionic sorbents. Modification of a zeolite may enhance adsorption capacities and ion selectivity. This research investigates the arsenic adsorption capacities of a modified Chabazite. This adsorption, coupled with a hollow fiber, microfiltration membrane ...


Development Of Ganglioside-Based Assays For The Identification Of Botulinum And Cholera Toxins Utilizing An Evanescent Wave Biosensor, Crystal M. Bedenbaugh Jun 2006

Development Of Ganglioside-Based Assays For The Identification Of Botulinum And Cholera Toxins Utilizing An Evanescent Wave Biosensor, Crystal M. Bedenbaugh

Graduate Theses and Dissertations

An evanescent wave fiber-optic biosensor was used in an effort to develop an assay for the rapid detection of two biological toxins: cholera toxin and botulinum toxin. The Analyte 2000 fiber-optic biosensor utilizes a sandwich immunoassay format. Gangliosides or liposomes are directly adsorbed to the surface of the fiber-optic waveguide through hydrophobic interactions. The waveguide is exposed to a sample containing the toxin of interest, then subsequently exposed to a polyclonal detection antibody conjugated to the fluorophore cyanine 5. Excitation light from a 635nm laser diode is propagated through the waveguide and fluorescent molecules within approximately 100nm of the waveguide ...


Lean Manufacturers Transcendence To Green Manufacturing: Correlating The Diffusion Of Lean And Green Manufacturing Systems, Gary G. Bergmiller Jun 2006

Lean Manufacturers Transcendence To Green Manufacturing: Correlating The Diffusion Of Lean And Green Manufacturing Systems, Gary G. Bergmiller

Graduate Theses and Dissertations

Scientific evidence of human impact on the natural environment, such as global warming, continues to mount. Green manufacturing systems that focus on minimizing environmental impact of manufacturing processes and products are ever more important to our sustainable future. Green manufacturing systems are slow to gain acceptance as manufacturers are focused on implementing Lean manufacturing systems, generally considered the most competitive manufacturing systems in the world.

In recent years, researchers and the US Environmental Protection Agency (EPA) have sought to "build a bridge" between Lean and Green manufacturing systems, in hopes that the rapid expanse of Lean can serve as a ...


Are Respiratory Behaviors Affected In Individuals With Adductor Spasmodic Dysphonia?, Katie Biedess Jun 2006

Are Respiratory Behaviors Affected In Individuals With Adductor Spasmodic Dysphonia?, Katie Biedess

Graduate Theses and Dissertations

Adductor spasmodic dysphonia (ADSD) is a focal dystonia that is characterized by voice breaks due to involuntary contractions of the adductor muscles of the vocal folds. These spasms can interfere with the coordination and balance of the respiratory and phonatory systems interfering with normal voice production. Disruptions in normal respiratory behaviors are well documented in inviduals with laryngeal disorders, including ADSD. Previous research regarding respiratory processes in ADSD has focused on airflow and pressure; however, there are many other parameters that have not been considered and may shed new light on the respiratory behaviors of individuals with ADSD. Therefore, the ...


Crystal Engineering Of Organic Compounds Including Pharmaceuticals, Joanna A. Bis Jun 2006

Crystal Engineering Of Organic Compounds Including Pharmaceuticals, Joanna A. Bis

Graduate Theses and Dissertations

Neutral or charge-assisted hydrogen bonds occurring between organic molecules represent strong and directional forces that mediate the molecular self-assembly into well defined supramolecular architectures. A proper understanding of hydrogen bonding interactions, their types, geometries, and occurrence in supramolecular motifs, is a prerequisite to crystal engineering, i.e. to the rational design of functional solid materials.Multiple-component organic crystals represent ideal systems to study the intermolecular interactions between the constituent molecules that can be pre-selected for their hydrogen bonding sites and geometrical capabilities. In particular, the systematic structural analysis of supramolecular systems that are comprised of simple molecules facilitates the development ...