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2012

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Foveon F13 Camera, David Shelley Jan 2012

Foveon F13 Camera, David Shelley

All Computer Science and Engineering Research

Most high-fidelity digital cameras currently available obtain their images using technology where individual pixels can only acquire a single color. Since the acquisition of multiple colors is necessary to capture a full colored image, picture resolution is lost due to difficulties in interpolation between non-adjacent, same color pixels. The resulting unsharp images create the need to find a new way to obtain these images without requiring interpolation between adjacent pixels. An innovative method to capture images with individual pixel cells consisting of three layers of photodetectors stacked vertically upon one another has been created to rectify this problem, but no …


Millennial Integration: Challenges Millennials Face In The Workplace And What They Can Do About Them, Chip Espinoza Jan 2012

Millennial Integration: Challenges Millennials Face In The Workplace And What They Can Do About Them, Chip Espinoza

Antioch University Dissertations & Theses

There is a monumental changing of the guard that is currently taking place in organizations due to demographic metabolism. One of the largest birth cohorts or generations in history (Baby Boomer) is beginning to retire while their predecessor (Builder) is almost completely out of the workforce. Gen X is hitting stride and on the cusp of inheriting the proverbial organizational mantle. The three aforementioned age cohorts have learned to play in the organizational sandbox together. However, a new age cohort (Millennial, a.k.a. Gen Y), equal or greater in size to the Baby Boomer cohort started entering the playground approximately ten …


Amino Acid Repeats Cause Extraordinary Coding Sequence Variation In The Social Amoeba Dictyostelium Discoideum, Clea Scala, Xiangjun Tian, Natasha J. Mehdiabadi, Margaret H. Smith, Gerda Saxer, Katie Stephens, Prince Buzombo, Joan E. Strassmann, David C. Queller Jan 2012

Amino Acid Repeats Cause Extraordinary Coding Sequence Variation In The Social Amoeba Dictyostelium Discoideum, Clea Scala, Xiangjun Tian, Natasha J. Mehdiabadi, Margaret H. Smith, Gerda Saxer, Katie Stephens, Prince Buzombo, Joan E. Strassmann, David C. Queller

Biology Faculty Research

Protein sequences are normally the most conserved elements of genomes owing to purifying selection to maintain their functions. We document an extraordinary amount of within-species protein sequence variation in the model eukaryote Dictyostelium discoideum stemming from triplet DNA repeats coding for long strings of single amino acids. D. discoideum has a very large number of such strings, many of which are polyglutamine repeats, the same sequence that causes various human neurological disorders in humans, like Huntington’s disease. We show here that D. discoideum coding repeat loci are highly variable among individuals, making D. discoideum a candidate for the most variable …


Early Warning System: Relay Sensor Deployment & Network Reliability Analysis, Zhicheng Yang Jan 2012

Early Warning System: Relay Sensor Deployment & Network Reliability Analysis, Zhicheng Yang

All Computer Science and Engineering Research

In this project, we continued Dr. Chipara's study, which developed an early warning system (EWS) to detect the vital signs of patients in order to help doctors to intervene in time [1]. Since the number of wards increased, the environment our system faced with became more complicated and our network became more sensitive. This project focused on finding reasons on the relays that didn't work and doing a reliability analysis on the network in one ward our study covered.


Soil Phosphorus Availability And Buffering Capacity In Eastern South Dakota Assessed Using Quantity-Intensity Relationships And Diffusive Gradients In Thin Films, Rose Eitemiller Jan 2012

Soil Phosphorus Availability And Buffering Capacity In Eastern South Dakota Assessed Using Quantity-Intensity Relationships And Diffusive Gradients In Thin Films, Rose Eitemiller

Electronic Theses and Dissertations

Phosphorus (P) availability is influenced by soil properties and depth, creating challenges for nutrient management across agricultural landscapes. This study evaluated two complementary approaches for quantifying P availability and adsorption dynamics in eastern South Dakota soils: Diffusive Gradients in Thin Films (DGT) and P quantity–intensity (Q–I) relationships. The objectives were to (1) quantify bioavailable P using DGT, (2) compare DGT measurements with established soil test P (STP), (3) evaluate Q–I parameters describing P adsorption characteristics, and (4) assess spatial variability in P availability across eastern South Dakota soils. DGT-measured P increased with STP levels and was strongly correlated with Bray-1, …


Building 21st Century Business Skills In High School Business Classrooms Using Digital Games And Simulations, Stacy Marcus Jan 2012

Building 21st Century Business Skills In High School Business Classrooms Using Digital Games And Simulations, Stacy Marcus

Graduate Research Papers

Digital games and simulations are often seen as fun activities to reward students but their potential is much greater. This literature review examined how integrating digital games and simulations into secondary business curriculum can help students build the skills needed for the 21st century workplace in an environment that is conducive to how they learn best. The effects of digital games and simulations on student motivation are also examined as well as how to assess student learning while using these tools. The information found came from peer-reviewed journals, books, and studies from the Web. Digital games and simulations have proven …


Bayesian Inference On Mixed-Effects Models With Skewed Distributions For Hiv Longitudinal Data, Ren Chen Jan 2012

Bayesian Inference On Mixed-Effects Models With Skewed Distributions For Hiv Longitudinal Data, Ren Chen

USF Tampa Graduate Theses and Dissertations

Statistical models have greatly improved our understanding of the pathogenesis of HIV-1 infection

and guided for the treatment of AIDS patients and evaluation of antiretroviral (ARV) therapies.

Although various statistical modeling and analysis methods have been applied for estimating the

parameters of HIV dynamics via mixed-effects models, a common assumption of distribution is

normal for random errors and random-effects. This assumption may lack the robustness against

departures from normality so may lead misleading or biased inference. Moreover, some covariates

such as CD4 cell count may be often measured with substantial errors. Bivariate clustered

(correlated) data are also commonly encountered in …


Crack Analysis In Silicon Solar Cells, Maria Ines Echeverria Molina Jan 2012

Crack Analysis In Silicon Solar Cells, Maria Ines Echeverria Molina

USF Tampa Graduate Theses and Dissertations

Solar cell business has been very critical and challenging since more efficient and low costs materials are required to decrease the costs and to increase the production yield for the amount of electrical energy converted from the Sun's energy. The silicon-based solar cell has proven to be the most efficient and cost-effective photovoltaic industrial device. However, the production cost of the solar cell increases due to the presence of cracks (internal as well as external) in the silicon wafer. The cracks of the wafer are monitored while fabricating the solar cell but the present monitoring techniques are not sufficient when …


Stable Isotope Analysis Of Busycon Sinistrum To Determine Fort Walton-Period Seasonality At St. Joseph Bay, Northwest Florida, Ryan Michael Harke Jan 2012

Stable Isotope Analysis Of Busycon Sinistrum To Determine Fort Walton-Period Seasonality At St. Joseph Bay, Northwest Florida, Ryan Michael Harke

USF Tampa Graduate Theses and Dissertations

ABSTRACT

Recent archaeological investigations indicate that coastal Fort Walton cultures in the St. Joseph Bay region of northwest Florida emphasized marine and estuarine foraging. These late prehistoric (A.D. 1000-1500) peoples collected fish, shellfish, and other aquatic resources. At the Richardson's Hammock site (8Gu10), radiocarbon-dated to about A.D. 1300, as at dozens of other shell middens around this salty bay, large gastropods were a major subsistence component. This adaptation is in sharp contrast with that of contemporaneous inland Fort Walton societies, who relied on maize agriculture. It is unknown whether coastal groups represent separate hunter-gatherer-fisher populations or seasonal migrations by inland …


Communication And Academic Vocabulary In Mathematics: A Content Analysis Of Prompts Eliciting Written Responses In Two Elementary Mathematics Textbooks, Christine M. Joseph Jan 2012

Communication And Academic Vocabulary In Mathematics: A Content Analysis Of Prompts Eliciting Written Responses In Two Elementary Mathematics Textbooks, Christine M. Joseph

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to investigate how writing in mathematics is treated in one 4th grade National Science Foundation (NSF)-funded mathematics textbook titled Everyday Mathematics and one publisher-generated textbook titled enVision MATH. The developed framework provided categories to support each of the research questions. The results indicate that writing is supported in both traditional and NSF developed 4th grade mathematics textbooks

Results also indicated the number of exercises and writing prompts was higher in the enVision MATH textbook. However, Everyday Mathematics had a higher percentage of exercises that were coded as writing prompts. The framework domains of content …


Linear Mixed-Effects Models: Applications To The Behavioral Sciences And Adolescent Community Health, Lizmarie Gabriela Maldonado Jan 2012

Linear Mixed-Effects Models: Applications To The Behavioral Sciences And Adolescent Community Health, Lizmarie Gabriela Maldonado

USF Tampa Graduate Theses and Dissertations

Linear mixed-effects (LME) modeling is a widely used statistical method for analyzing repeated measures or longitudinal data. Such longitudinal studies typically aim to investigate and describe the trajectory of a desired outcome. Longitudinal data have the advantage over cross-sectional data by providing more accuracy for the model. LME models allow researchers to account for random variation among individuals and between individuals.

In this project, adolescent health was chosen as a topic of research due to the many changes that occur during this crucial time period as a precursor to overall well-being in adult life. Understanding the factors that influence how …


Bi-Integrable And Tri-Integrable Couplings And Their Hamiltonian Structures, Jinghan Meng Jan 2012

Bi-Integrable And Tri-Integrable Couplings And Their Hamiltonian Structures, Jinghan Meng

USF Tampa Graduate Theses and Dissertations

An investigation into structures of bi-integrable and tri-integrable couplings is undertaken. Our study is based on semi-direct sums of matrix Lie algebras. By introducing new classes of matrix loop Lie algebras, we form new Lax pairs and generate several new bi-integrable and tri-integrable couplings of soliton hierarchies through zero curvature equations. Moreover, we discuss properties of the resulting bi-integrable couplings, including infinitely many commuting symmetries and conserved densities. Their Hamiltonian structures are furnished by applying the variational identities associated with the presented matrix loop Lie algebras.

The goal of this dissertation is to demonstrate the efficiency of our approach and …


Spatial And Temporal Variability Of Remotely Sensed Ocean Color Parameters In Coral Reef Regions, Daniel Brooks Otis Jan 2012

Spatial And Temporal Variability Of Remotely Sensed Ocean Color Parameters In Coral Reef Regions, Daniel Brooks Otis

USF Tampa Graduate Theses and Dissertations

The variability of water-column absorption due to colored dissolved organic matter (CDOM) and phytoplankton in coral reef regions is the focus of this study. Hydrographic and CDOM absorption measurements made on the Bahamas Banks and in Exuma Sound during the spring of 1999 and 2000 showed that values of salinity and CDOM absorption at 440nm were higher on the banks (37.18 psu, 0.06 m^-1), compared to Exuma Sound (37.04 psu, 0.03 m^-1). Spatial patterns of CDOM absorption in Exuma Sound revealed that plumes of CDOM-rich water flow into Exuma Sound from the surrounding banks. To examine absorption variability in reef …


Remote Sensing Of Whitings In The Bahamas, Ryan Allen Lloyd Jan 2012

Remote Sensing Of Whitings In The Bahamas, Ryan Allen Lloyd

USF Tampa Graduate Theses and Dissertations

Whitings on both the Great Bahama Bank (GBB) and Little Bahama Bank (LBB) were evaluated using data collected from 2000-2010 by the Moderate Resolution Imaging Spectroradiometer (MODIS) instruments onboard the Terra and Aqua satellites. A semi-objective method was developed to classify whiting patches from other look-alike features using the recently developed Floating Algae Index (FAI) algorithm, an empirical cloud masking algorithm, and a gradient analysis from the 250-m resolution MODIS data. A total of 1,500 images with minimal cloud cover was used to calculate long-term and seasonal trends as well as an average daily coverage for both banks. Annual and …


A Comparison Of The Perceptions Of School Work Culture By Administrators And Faculty In The Public Charter And Non-Charter Elementary Schools Of A Central Florida County, Wayne Anthony Quin Jan 2012

A Comparison Of The Perceptions Of School Work Culture By Administrators And Faculty In The Public Charter And Non-Charter Elementary Schools Of A Central Florida County, Wayne Anthony Quin

USF Tampa Graduate Theses and Dissertations

Abstract

This study investigated perceptions of school work culture of instructional staff members (administrators and faculty) in public charter and public non-charter elementary schools in a large urban metropolitan county of Central Florida by assessing differences in perceptions of administrators and faculty related to school work culture, perceptions between school administrators and faculty, and the interaction between type of school.

The School Work Culture Profile (SWCP), a paper-and-pencil survey, was designed in 1988 by Snyder to obtain a measure of a school's work culture. The SWCP uses a Likert scale to assess the overall perception and four sub-domains of planning, …


Optical Detection And Classification Of Phytoplankton Taxa Through Spectral Analysis, Daniel Tyler Sensi Jan 2012

Optical Detection And Classification Of Phytoplankton Taxa Through Spectral Analysis, Daniel Tyler Sensi

USF Tampa Graduate Theses and Dissertations

Phytoplankton serve as the bottom of the marine food web and therefore play an essential role in marine ecosystems. On the other hand, coastal phytoplankton communities can adversely affect the marine ecosystem and humans. A variety of techniques have been developed to measure and study phytoplankton, including in situ methods (e.g., flow cytometry) and laboratory methods (e.g., microscopic taxonomy). These provide accurate measurements of phytoplankton taxa and concentrations, yet they are limited in space and time, and synoptic information is difficult to obtain with these techniques.

Optical remote sensing may provide complementary information for its synoptic nature, as demonstrated by …


Design Of Novel Inhibitors For Infectious Diseases Using Structure-Based Drug Design: Virtual Screening, Homology Modeling And Molecular Dynamics, Divya Ramamoorthy Jan 2012

Design Of Novel Inhibitors For Infectious Diseases Using Structure-Based Drug Design: Virtual Screening, Homology Modeling And Molecular Dynamics, Divya Ramamoorthy

USF Tampa Graduate Theses and Dissertations

The main aim of the study in this thesis was to use structure-based protocols to design new drugs for enzymes, DXS and DXR in the non mevalonate pathway. Another aim of this study was to identify the dimer interface in E.coli FabH as an allosteric binding site for designing new class of anti-infective drugs. We have attempted to identify potential inhibitors for DXS by docking the NCI Diversity set compounds, compound libraries available from GSK-MMV and St. Jude's Children's research center. FabH dimer interface has been identified as a potential target using SiteMap, Alanine mutagenesis and docking studies.

The first …


Growth And Characterization Of Functional Nanoparticulate Films By A Microwave Plasma-Assisted Spray Deposition Process, Ted Wangensteen Jan 2012

Growth And Characterization Of Functional Nanoparticulate Films By A Microwave Plasma-Assisted Spray Deposition Process, Ted Wangensteen

USF Tampa Graduate Theses and Dissertations

Nanoparticle and nanoparticulate films have been grown by a unique approach combining a microwave and nebulized droplets where the concentration and thus the resulting particle size can be controlled. The goal of such a scalable approach was to achieve it with the least number of steps, and without using expensive high purity chemicals or the precautions necessary to work with such chemicals. This approach was developed as a result of first using a laser unsuccessfully to achieve the desired films and particles. Some problems with the laser approach for growing desired films were solved by substituting the higher energy microwave …


Assessment Of Methods To Manipulate Thermal Emission And Evaluate The Quality Of Thermal Radiation For Direct Energy Conversion, Samantha Wijewardane Jan 2012

Assessment Of Methods To Manipulate Thermal Emission And Evaluate The Quality Of Thermal Radiation For Direct Energy Conversion, Samantha Wijewardane

USF Tampa Graduate Theses and Dissertations

ABSTRACT

Control of spectral thermal emission from surfaces may be desirable in some energy related applications, such as nano-scale antenna energy conversion and thermophotovoltaic conversion. There are a number of methods, from commercially available paints to advanced surface gratings that can be used to modify the thermal emission from a surface. To find out the proper emission controlling technique for a given energy conversion method all the surface emission controlling methods are comprehensively reviewed regarding the emission control capabilities and the range of possible applications. Radiation with high degree of coherence can be emitted using advanced surface emission controlling techniques. …


Digital Gaming As A Learning Tool : A Literature Review, Seth Weylin Vickers Jan 2012

Digital Gaming As A Learning Tool : A Literature Review, Seth Weylin Vickers

Graduate Research Papers

This review of literature focuses on the uses of digital gaming within learning environments. Using academic journal articles, the author reviews the advantages and disadvantages of using digital games, ways instructors are using digital games, the uses of educational as well as recreational digital games, considerations for implementing digital games, and an overview on the importance of digital security. The benefits include increased motivation, collaboration, and the increased opportunity of a learner potentially entering the flow experience. The disadvantages include health risks as well as some learners' negative attitudes towards digital gaming. The author recommends instructors to consider using digital …


Inhibition Of Bone Loss By Cissus Quadrangularis In Mice: A Preliminary Report, Jameela Banu, Erika Varela, Ali N. Bahadur, Raheela Soomro, Nishu Kazi, Gabriel Fernandes Jan 2012

Inhibition Of Bone Loss By Cissus Quadrangularis In Mice: A Preliminary Report, Jameela Banu, Erika Varela, Ali N. Bahadur, Raheela Soomro, Nishu Kazi, Gabriel Fernandes

Health & Biomedical Sciences Faculty Publications

Women drastically loose bone during and after menopause leading to osteoporosis, a disease characterized by low bone mass increasing the risk of fractures with minor trauma. Existing therapies mainly reduce bone resorption, however, all existing drugs have severe side effects. Recently, the focus is to identify alternative medicines that can prevent and treat osteoporosis with minimal or no side effects. We used Cissus quadrangularis (CQ), a medicinal herb, to determine its effects on bone loss after ovariectomy in C57BL/6 mice. Two-month old mice were either sham operated or ovariectomized and fed CQ diet. After eleven weeks, mice were sacrificed and …


Relationship Between Carbon Dioxide In Balcarka Cave And Adjacent Soils In The Moravian Karst Region Of The Czech Republic, Jiří Faimon, Monika Ličbinská, Petr Zajíček Jan 2012

Relationship Between Carbon Dioxide In Balcarka Cave And Adjacent Soils In The Moravian Karst Region Of The Czech Republic, Jiří Faimon, Monika Ličbinská, Petr Zajíček

International Journal of Speleology

Carbon dioxide concentration, air temperature, and humidity were monitored at (1) two cave sites and (2) three adjacent karst soils. The data over a one-year period are supported by dripwater chemistry and cave visiting frequency. The results indicate that the sources of cave CO2 are anthropogenic and epikarstic ones in addition to ordinary soils. Epikarstic CO2 produced under almost stationary conditions probably control dripwater chemistry and cave’s CO2 maxima. Based on breathing and door opening, anthropogenic activity affects instantaneous cave CO2 levels, depending on site volume/position and visitor number. A conceptual model of the CO2 dynamics of the soil-cave system …


Volcanic Caves: Priorities For Conserving The Azorean Endemic Troglobiont Species, Paulo A.V. Borges Prof., Pedro Cardoso, Isabel R. Amorim, Fernando Pereira, João P. Constância, João C. Nunes, Paulo Barcelos, Paulino Costa, Rosalina Gabriel, Maria L. Dapkevicius Jan 2012

Volcanic Caves: Priorities For Conserving The Azorean Endemic Troglobiont Species, Paulo A.V. Borges Prof., Pedro Cardoso, Isabel R. Amorim, Fernando Pereira, João P. Constância, João C. Nunes, Paulo Barcelos, Paulino Costa, Rosalina Gabriel, Maria L. Dapkevicius

International Journal of Speleology

Azorean lava-tubes and volcanic pits adequately sampled for arthropod fauna were evaluated for species diversity and rarity. An iterative partial multiple regression analysis was performed to produce a multi-criteria index (Importance Value for Cave Conservation, IV-CC) incorporating arthropod species diversity indices but also including indices qualifying cave geological and management features (e.g., the diversity of geological structures, threats, accessibility). Additionally, we calculated complementarity solutions (irreplaceability and Fraction-of-Spare measures) for each cave with different targets per species, i.e., the minimum number of caves needed for each species to be represented either once or twice. Our results clearly show that to preserve …


In Memorium: Joaquin Montoriol Pous Jan 2012

In Memorium: Joaquin Montoriol Pous

International Journal of Speleology

No abstract provided.


Speleogenetic Effects Of Interaction Between Deeply Derived Fracture-Conduit Flow And Intrastratal Matrix Flow In Hypogene Karst Settings, Alexander Klimchouk, Elizaveta Tymokhina, Gennadiy Amelichev Jan 2012

Speleogenetic Effects Of Interaction Between Deeply Derived Fracture-Conduit Flow And Intrastratal Matrix Flow In Hypogene Karst Settings, Alexander Klimchouk, Elizaveta Tymokhina, Gennadiy Amelichev

International Journal of Speleology

In carbonate rocks, especially in those with high primary porosity such as most Cenozoic carbonates, the interaction between deeply derived rising flow through sub-vertical fracture-controlled conduits and intrastratal matrix flow of shallower systems can invoke mixing corrosion and result in prominent speleogenetic effects. This paper outlines a conceptual model of such interaction and provides instructive field examples of relevant morphological effects from two different regions within the Prichernomorsky (north Black Sea) basin, where karst features are developed in lower Pliocene, Eocene and Paleocene limestones. In the Crimean fore-mountain region, extensive steep to vertical limestone scarps formed through recent exposure of …


The World’S Deepest Subterranean Community - Krubera-Voronja Cave (Western Caucasus), Alberto Sendra, Ana Sofia P.S. Reboleira Jan 2012

The World’S Deepest Subterranean Community - Krubera-Voronja Cave (Western Caucasus), Alberto Sendra, Ana Sofia P.S. Reboleira

International Journal of Speleology

Subsurface biota extends over a wide variety of habitats that can be spatially interconnected. The largest communities of this subsurface biota inhabit cavities and are well known mainly in caves where biologists are able to have access. Data about deep subterranean communities and arthropods living under one thousand meters was unknown.

An expedition to world’s deepest cave, Krubera-Voronja in Western Caucasus, revealed an interesting subterranean community, living below 2000 meters and represented by more than 12 species of arthropods, including several new species for science. This deep cave biota is composed of troglobionts and also epigean species, that can penetrate …


Management In A Neotropical Show Cave: Planning For Invertebrates Conservation, Thais Giovannini Pellegrini, Rodrigo Lopes Ferreira Jan 2012

Management In A Neotropical Show Cave: Planning For Invertebrates Conservation, Thais Giovannini Pellegrini, Rodrigo Lopes Ferreira

International Journal of Speleology

Lapa Nova is a dolomitic cave about 4.5 km long located in northwestern Minas Gerais state, Brazil. The cave experiences intense tourism, concentrated over a single period of the year, during the Feast of Our Lady of Lapa. In order to evaluate the impacts felt by the invertebrate community from this tourism, a new methodology was proposed. Four types of areas (intense visitation area, outlying visitation areas, moderate visitation areas and no-visitation areas) were sampled for invertebrates. There was one sampling prior and another on the last day of the 128th feast, to evaluate the effects of visitation on …


John Collier, Thomas Edison And The Educational Promotion Of Moving Pictures, Amanda R. Keeler Jan 2012

John Collier, Thomas Edison And The Educational Promotion Of Moving Pictures, Amanda R. Keeler

College of Communication Faculty Research and Publications

No abstract provided.


Acquiring Os X File Handles Through Forensic Memory Analysis, Andrew F. Hay, Gilbert L. Peterson Jan 2012

Acquiring Os X File Handles Through Forensic Memory Analysis, Andrew F. Hay, Gilbert L. Peterson

Faculty Publications

Memory analysis has become a critical capability in digital forensics because it provides insight into system state that cannot be fully represented through traditional media analysis. The volafox open source project has begun the work of structured memory analysis for OS X with support for a limited set of kernel structures. This paper addresses one memory analysis deficiency on OS X with the introduction of a new volafox module for parsing file handles associated with running processes. The developed module outputs information comparable to the UNIX lsof (list open files) command, which is used to validate the results.


Variable Object Research: Methods And Processes, Dan Broadbent Jan 2012

Variable Object Research: Methods And Processes, Dan Broadbent

Faculty Publications

Some objects in the sky vary over time in terms of how much of their energy reaches the earth. Studying how the energy varies, and identifying any periodicities, will give clues as to what is actually happening at the source.

The purpose of this paper is to document the current methods involved in gathering and processing data, specifically on the variable object Markarian 501. The intent is that this will provide a foundation for later work to automate the process.