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2006

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A Collaborative, Hierarchical, Incremental, And Problem Solving Information Systems Development Model, Timothy Joseph Burns Dec 2006

A Collaborative, Hierarchical, Incremental, And Problem Solving Information Systems Development Model, Timothy Joseph Burns

Dissertations

The "software crisis" has been a much discussed and debated topic in Information Systems research. A core cause of the crisis is often identified as the methodologies and approaches used to develop information systems. Thus, over the years a multitude of methodologies have emerged in support of quality software. While many of these methodologies have been effective, research has shown that system development is a highly circumstantial process, and that no one methodology can be optimal in every context of every project. It is also a fact that system development practitioners have employed ad hoc approaches to modify formal methodologies ...


High Resolution Studies Of Complex Solar Active Regions, Na Deng Dec 2006

High Resolution Studies Of Complex Solar Active Regions, Na Deng

Dissertations

Flares and Coronal Mass Ejections (CMEs) are energetic events, which can even impact the near-Earth environment and are the principal source of space weather. Most of them originate in solar active regions. The most violent events are produced in sunspots with a complex magnetic field topology. Studying their morphology and dynamics is helpful in understanding the energy accumulation and release mechanisms for flares and CMEs, which are intriguing problems in solar physics.

The study of complex active regions is based on high-resolution observations from space missions and new instruments at the Big Bear Solar Observatory (BBSO). Adaptive optics (AG) in ...


Modeling Projection Neuron And Neuromodulatory Effects On A Rhythmic Neuronal Network, Nicholas Kintos Dec 2006

Modeling Projection Neuron And Neuromodulatory Effects On A Rhythmic Neuronal Network, Nicholas Kintos

Dissertations

Projection neurons shape the activity of many neural networks. In particular, neuromodulatory substances, which are often released by projection neurons, alter the cellular and/or synaptic properties within a target network. However, neural networks in turn influence projection neuron input via synaptic feedback. This dissertation uses mathematical and biophysically-realistic modeling to investigate these issues in the gastric mill (chewing) motor network of the crab, Cancer borealis. The projection neuron MCN1 elicits a gastric mill rhythm in which the LG neuron and INTl burst in anti-phase due to their reciprocal inhibition. However, bath application of the neuromodulator PK elicits a similar ...


Small And Large-Scale Magnetic Fields Involved With Solar Flares, Chang Liu Dec 2006

Small And Large-Scale Magnetic Fields Involved With Solar Flares, Chang Liu

Dissertations

Solar flares are generally identified as an important source of disturbances that affect space weather, while many aspects of the basic flare process are still not well understood. The purpose of the present work has been to investigate the small and large-scale magnetic structures and their evolution associated with flares in the context of magnetic reconnection, based on which the goal of this dissertation is to further the understanding of the various properties of flares and related phenomena, including their origin, precursors, and evolution of morphology in solar atmosphere.

The research presented in this dissertation relied upon multiwavelength observations of ...


Community-Based Evaluation Of The Air Toxic Provisions Of Title Iii Of The 1990 Clean Air Act Amendments : Risks, Costs And Benefits, Keith C. Silverman Dec 2006

Community-Based Evaluation Of The Air Toxic Provisions Of Title Iii Of The 1990 Clean Air Act Amendments : Risks, Costs And Benefits, Keith C. Silverman

Dissertations

Hazardous air pollutants (HAPs) are those pollutants that are known or suspected to cause cancer, serious health effects, or adverse environmental effects. People exposed to HAPs at sufficient concentrations and durations may have an increased risk of getting cancer or experiencing other health effects. The 1990 Amendments to the Clean Air Act (CAAA) directed the U.S. Environmental Protection Agency (USEPA) to use technology-based air pollution control measures to significantly reduce emissions of HAPs from major sources of air pollution, followed by a risk-based assessment to address any remaining or residual health risks.

This study retrospectively assessed the public health ...


The Unbalanced Classification Problem: Detecting Breaches In Security, Paul Evangelista Dec 2006

The Unbalanced Classification Problem: Detecting Breaches In Security, Paul Evangelista

West Point ETD

This research proposes several methods designed to improve solutions for security classification problems. The security classification problem involves unbalanced, high-dimensional, binary classification problems that are prevalent today. The imbalance within this data involves a significant majority of the negative class and a minority positive class. Any system that needs protection from malicious activity, intruders, theft, or other types of breaches in security must address this problem. These breaches in security are considered instances of the positive class. Given numerical data that represent observations or instances which require classification, state of the art machine learning algorithms can be applied. However, the ...


Incorporation Of Capillary-Channeled Polymer (C-Cp) Fibers Into Micropipette Tips For Solid Phase Extraction With Applications In Bioanalysis, Donald Fornea Dec 2006

Incorporation Of Capillary-Channeled Polymer (C-Cp) Fibers Into Micropipette Tips For Solid Phase Extraction With Applications In Bioanalysis, Donald Fornea

All Theses

Solid phase extraction (SPE), is a widely used sample preparation method that is currently experiencing a surge in research interest, clever architecture/format development, and stationary phase characterization.1-3 SPE devices commonly exist in syringe, cartridge, disk, and micropipette tip formats.4 Micropipette tip SPE has enhanced the determination of proteins by electrospray ionization (ESI) and matrix assisted laser desorption ionization (MALDI) mass spectrometry (MS) by handling micro-liter volumes of sample and buffer removal/solvent exchange.5-7 Buffers have deleterious effects on ionization taking place in MS sources due to preferential ionization, ion suppression effects, and the formation of adduct ...


Change-Point Tests For Precipitation Data, Michael Robbins Dec 2006

Change-Point Tests For Precipitation Data, Michael Robbins

All Theses

A new method is required for change-point testing of precipitation data that is capable of applying valid precipitation models. First, stochastic precipation models are researched and classified. Typically, the occurrence of rain is modeled using a two-state, first-order Markov chain, and the intensity of rain is modeled using a two-parameter gamma distribution. Using the likelihood ratio test statistic, methods are devoloped for testing for fixed and unknown change-points. These methods are developed for various models, including the MC/gamma model and simplified versions. The distribution of the LRT is unknown, however its asymptotic distribution is known for both the fixed ...


Indoor Air Quality: Determination Of Voc's In A Reproductive Clinic., Miriam Rachel Trivette Dec 2006

Indoor Air Quality: Determination Of Voc's In A Reproductive Clinic., Miriam Rachel Trivette

Electronic Theses and Dissertations

The purpose of this study was to perform an indoor air quality (IAQ) investigation at the Center for Applied Reproductive Science (CARS) to assess whether VOCs exist at levels dangerous to embryo. Formaldehyde, n-hexane, benzene, and styrene concentrations were measured at six locations. Formaldehyde concentrations were comparable to office and residential indoor air. N-hexane, benzene, and styrene were not detected. In addition, acetaldehyde, ethanol, and isopropyl alcohol were detected. IAQ parameters (carbon dioxide, temperature, humidity, pressure, and particulates) were measured at 22 sites monthly for one year. Temperature and humidity readings were within Environmental Protection Agency recommendations. Particulate concentrations were ...


Screencrayons: Using Screen Captures For Annotation And Research, Trent Alan Taufer Dec 2006

Screencrayons: Using Screen Captures For Annotation And Research, Trent Alan Taufer

Theses and Dissertations

In a world full of digital information we should be able to easily collect, organize, annotate, and leverage information from many different sources. This should be easy to do and not interrupt our normal workflow. A system to support information collection and organization should be user-friendly and as unobtrusive as possible, while still allowing for flexible and intelligent annotation. It should also be able to leverage the inherent information content of a collection of annotated information. We present a system that will demonstrate how these ideas can come together to make information collection easier and more productive. The system facilitates ...


Onset And Persistence Of Biogenic Meromixis In A Filling Pit Lake-A Limnological Perspective , Oscar Flite Dec 2006

Onset And Persistence Of Biogenic Meromixis In A Filling Pit Lake-A Limnological Perspective , Oscar Flite

All Dissertations

Open pit mining usually results in a void that, over time, fills with water and becomes a pit lake. The goal for pit lakes is to create sustainable systems that positively contribute to local and regional watersheds. One long-standing hypothesis for attaining the goal of sustainability has been to create and maintain meromictic lakes (lakes that do not completely mix on a yearly cycle). It is believed that meromixis minimizes atmospheric oxygen exposure to pit walls and concomitant acid generation and minimizes reentrainment of metals to the upper waters during seasonal mixes. This seems to be a reasonable goal but ...


The Effect Of Water Droplet Oscillations On The Scavenging Efficiency Of Micron Sized Particles, Raymond Mcdonnell Dec 2006

The Effect Of Water Droplet Oscillations On The Scavenging Efficiency Of Micron Sized Particles, Raymond Mcdonnell

All Theses

It has been hypothesized that drop oscillations and vortex shedding within the droplet wake affect the scavenging efficiency, E, of particles. However, no conclusive results have been presented on the effect these phenomena might have on particle scavenging. To address this need, experiments were conducted using oscillating water drops and water drops damped by the addition of glycerol. The scavenging efficiencies were measured for millimeter-sized droplets scavenging micron-sized particles. These results show that E is increased by drop oscillations where the particle diameter is large, but E is decreased by these oscillations when the particle diameter is small.


Remediation Of Risks In Natural Gas Storage Produced Waters: The Potential Use Of Constructed Wetland Treatment Systems, Brenda Johnson Dec 2006

Remediation Of Risks In Natural Gas Storage Produced Waters: The Potential Use Of Constructed Wetland Treatment Systems, Brenda Johnson

All Theses

Natural gas storage produced waters (NGSPWs) are generated in large volumes, vary in composition, and often contain constituents in concentrations and forms that are toxic to receiving system biota. This research had three major objectives: 1) Characterize NGSPWs to discern the constituents of concern present in these waters; 2) Design and measure performance of a pilot-scale hybrid constructed wetland treatments system (CWTS) for treating NGSPWs, and; 3) Discern the reliability of the Turner Designs TD500 handheld fluorometer for measurement of oil-in-water in produced waters containing algae. Produced waters contained chlorides, metals, and organics as constituents of concern. Using simulated produced ...


Occurrence And Control Of Large Patch (Rhizoctonia Solani Ag 2`2 «Lp«On Seashore Paspalum (Paspalum Vaginatum O. Swartz) In South Carolina, Alejandro Canegallo Dec 2006

Occurrence And Control Of Large Patch (Rhizoctonia Solani Ag 2`2 «Lp«On Seashore Paspalum (Paspalum Vaginatum O. Swartz) In South Carolina, Alejandro Canegallo

All Theses

Seashore paspalum is a new turfgrass being evaluated in the southeastern United States due to its tolerance to salinity and sodicity. Rhizoctonia solani AG 2-2 `LP` was isolated from seashore paspalum exhibiting symptoms typical of Large Patch (LP). The disease was identified based on field symptoms, lesions on the plant, and the fungus identified based on cultural characteristics, multinucleate hyphal cells, and anastomosis with a known tester isolate of R. solani AG 2-2 `LP` from zoysia grass.
Two research putting greens were constructed in 2005 located in Florence, SC and near Bluffton, SC and planted to seashore paspalum cultivars SeaIsle ...


Harmonic Detection Of Resonance In Micro- And Nano- Cantilevers, Jay Gaillard Dec 2006

Harmonic Detection Of Resonance In Micro- And Nano- Cantilevers, Jay Gaillard

All Dissertations

Over the past decade there has been an explosion in the study of cantilevered beams on the micron and submicron dimension. The applications and research that involve these structures include state-of-the-art electronic components, sensors, and more recently, studies aimed at elucidating the mechanical properties of cantilevered carbon nanotubes and semiconducting nanowires. In nanoelectro-mechanical systems (NEMS), it is desirable to develop a capacitive readout method involving only two electrodes that are fully compliant with standard CMOS technology. However, the main drawback with this method is the ability to detect resonance in the presence of parasitic capacitance, which is due to the ...


Assembly And Modification Of A Hyperthermal And Low Energy Ion Beamline For Detecting Electron-Hole Pair Production In Schottky Diodes, Matthew Ray Dec 2006

Assembly And Modification Of A Hyperthermal And Low Energy Ion Beamline For Detecting Electron-Hole Pair Production In Schottky Diodes, Matthew Ray

All Theses

A hyperthermal and low energy ion beamline to measure electron-hole pair production due to ion bombardment of Schottky diodes has been modified and assembled.
A brief overview of the instrument is given and the reason for operating the ion beamline in the hyperthermal and low energy regime is discussed. The capabilities of the ion beamline are unique and provide the means to measure quantities that offer insight into various energy exchange mechanisms that occur at surfaces. Combined with the ability to accept Schottky diode samples, the beamline is capable of measuring both charge transfer and electron-hole pair production caused by ...


Perfluoroalkyl (Aryl) Sulfonimide Zwitterions, Hua Mei Dec 2006

Perfluoroalkyl (Aryl) Sulfonimide Zwitterions, Hua Mei

All Dissertations

This research focuses on superacid perfluoroalkyl(aryl) sulfonimides and their derivatives as a source of stable zwitterionic salts. The strong resonance stabilization of sulfonimides imparts unexpected stability to the zwitterions.
Two types of zwitterions were investigated. The first are symmetrical diaryliodonium zwitterions (DZs) as potential photo acid generators (PAGs) for microlithography. Driven by the demand for smaller feature sizes in the microelectronics industry, microlithography using shorter wavelength light has evolved and new PAGs are of interest. New DZs are potentially useful because they have good thermal stability and may be structurally modified to alter their spectral absorption characteristics. As an ...


Toxicological Effects Of Endocrine Disrupting Compounds In Bluegill, Pamela Truman Dec 2006

Toxicological Effects Of Endocrine Disrupting Compounds In Bluegill, Pamela Truman

All Theses

The water quality in the Reedy River basin has been shown to be impacted from the diverse and highly urbanized land uses within the watershed. The objective of this study was to examine the observed toxicological effects of EDCs that may be present in the Reedy River watershed by using a suite of biomarkers that were measured in indigenous fish to characterize the exposure and biological effects of these contaminants. Bluegill were analyzed for unnatural estrogenic effects such as: 1) Vitellogenin (VTG) 2) Activity of estrogenic compounds in bile extractions 3) UDP-glucuronosyltransferase (UGT) activity. This biomarker study provides a more ...


Online Resources For Late Additions To The Solar Nebula, Allen Parker Dec 2006

Online Resources For Late Additions To The Solar Nebula, Allen Parker

All Theses

The presence of an excess of short-lived radionuclides in the early protoplanetary disk has been inferred from studying how the distribution of the abundances, in materials like Ca-Al-rich inclusions, differ from the solar abundance distribution (SAD). The likely source of these radioactivites is a supernova that ejected material into the early solar system. This thesis will discuss the solar abundance distribution and how a supernova may have contributed a 'late addition' of material into the early solar system. In addition, we have constructed online resources for studying these topics. This thesis will outline the Solar Abundance Tool, which allows a ...


Structure Learning Of A Behavior Network For Context Dependent Adaptability, Ou Li Dec 2006

Structure Learning Of A Behavior Network For Context Dependent Adaptability, Ou Li

Computer Science Theses

One mechanism for an intelligent agent to adapt to substantial environmental changes is to change its decision making structure. Pervious work in this area has developed a context-dependent behavior selection architecture that uses structure change, i.e., changing the mutual inhibition structures of a behavior network, as the main mechanism to generate different behavior patterns according to different behavioral contexts. Given the important of network structure, this work investigates how the structure of a behavior network can be learned. We developed a structure learning method based on generic algorithm and applied it to a model crayfish that needs to survive ...


Analysis Of Near-Infrared Phase Effects On Biometric Iris Data, Brady Roos Stevenson Dec 2006

Analysis Of Near-Infrared Phase Effects On Biometric Iris Data, Brady Roos Stevenson

Theses and Dissertations

The purpose of this research is to ascertain potential iris scan data variations from near infrared waves derived from fluorescent illumination. Prior studies of iris data variances from infrared wave interference of halogen, incandescent, and sunlight with iris cameras suggest that similar changes may exist under near infrared wavelengths from fluorescent light. The concern is that the fluorescent energy emission may interfere with the near infrared detection of an iris camera. An iris camera is used to measure human eye characteristics known as biometrics. If such infrared emission is statistically significant, then it can alter the validity of the iris ...


Characterization Of Capillary-Channeled Polymer Fibers As Stationary Phases For High-Performance Liquid Chromatography Of Macromolecules, Dwella Nelson Dec 2006

Characterization Of Capillary-Channeled Polymer Fibers As Stationary Phases For High-Performance Liquid Chromatography Of Macromolecules, Dwella Nelson

All Dissertations

Capillary-channeled polymer (C-CP) fibers are being developed and characterized as high-performance liquid chromatography (HPLC) stationary phases for reversed-phase separations of proteins. Conventional porous phases are not well suited for separating large macromolecules due to the slow diffusivity of the molecules, large diffusional distances, and stagnant mobile phase zones within the column. Stationary phases are continually being developed to address the challenges associated with HPLC of proteins and other macromolecules in general. C-CP fiber stationary phases are an alternative to conventional bead technology and offer a variety of chemical and physical advantages. The fibers can be selected for their chemical functionality ...


Managing Product Line Asset Bases, John Hunt Dec 2006

Managing Product Line Asset Bases, John Hunt

All Dissertations

Product lines are predicated on collecting assets common to the desired product portfolio, commonly known as the asset base. For many product lines, the size of asset base has become large enough to create a variety of difficulties. The techniques for managing large product line asset bases are unaddressed in the literature.
This research presents new techniques that take advantage of asset base characteristics, unavailable in more general collections, to both reduce the number of assets and to organize the asset base that go beyond what is possible with other software collections. The result is an asset base that is ...


The Molecular And Ecophysiological Roles Of Rubisco Activase And Rubisco Activase Likes In Photosynthetic Thermal Regulation Of Acer Rubrum And Arabidopsis Thaliana , David Weston Dec 2006

The Molecular And Ecophysiological Roles Of Rubisco Activase And Rubisco Activase Likes In Photosynthetic Thermal Regulation Of Acer Rubrum And Arabidopsis Thaliana , David Weston

All Dissertations

Determining the consequences of human impact on our current and future climate is proving to be to be one of the greater challenges in modern biology. Current global models employing coupled atmosphere and terrestrial carbon feedbacks range in their predictions from the inconsequential to that of vast food shortages and species extinctions. However, there is hope that the emergence of new molecular approaches will revolutionize our understanding of plant and animal responses to a changing environment, allowing for higher predictive power when scaling up from the level of the individual to ecosystem-scale processes. This dissertation is an initial attempt for ...


Analyzing The Effects Of Adolescent Risky Behaviors On Suicidal Ideation, Marchelle Elizabeth Sanchez Dec 2006

Analyzing The Effects Of Adolescent Risky Behaviors On Suicidal Ideation, Marchelle Elizabeth Sanchez

Mathematics Theses

This study is an analysis of adolescent risk behaviors contributing to an increased rate of suicidal ideation for 12 to 18 year olds. The Youth Risk Behavior Surveillance System Survey (YRBSS) is an epidemiologic survey designed to monitor the prevalence of risky behaviors of adolescents in middle and high school1. The YRBSS is a complex sample survey with a three-stage cluster design. Multiple logistic regression is used to analyze the data, including methods of analysis to address issues in complex survey design. Results of this study indicate several different risk factors that influence the rate of suicidal ideation among adolescents ...


Qos Multimedia Multicast Routing: A Component Based Primal Dual Approach, Faheem Akhtar Hussain Dec 2006

Qos Multimedia Multicast Routing: A Component Based Primal Dual Approach, Faheem Akhtar Hussain

Computer Science Theses

The QoS Steiner Tree Problem asks for the most cost efficient way to multicast multimedia to a heterogeneous collection of users with different data consumption rates. We assume that the cost of using a link is not constant but rather depends on the maximum bandwidth routed through the link. Formally, given a graph with costs on the edges, a source node and a set of terminal nodes, each one with a bandwidth requirement, the goal is to find a Steiner tree containing the source, and the cheapest assignment of bandwidth to each of its edges so that each source-to-terminal path ...


An Agent Based Transaction Manager For Multidatabase Systems, Sugandhi Madiraju Dec 2006

An Agent Based Transaction Manager For Multidatabase Systems, Sugandhi Madiraju

Computer Science Theses

A multidatabase system (MDBMS) is a facility that allows users to access data located in multiple autonomous database management systems (DBMSs) at different sites. To ensure global atomicity for multidatabase transactions, a reliable global atomic commitment protocol is a possible solution. In this protocol a centralized transaction manager (TM) receives global transactions, submits subtransactions to the appropriate sites via AGENTS. An AGENT is a component of MDBS that runs on each site; AGENTS after receiving subtransactions from the transaction manager perform the transaction and send the results back to TM. We have presented a unique proof-of-concept, a JAVA application for ...


Scalable Proxy Architecture For Mobile And Peer-To-Peer Networks, Praveena Jayanthi Dec 2006

Scalable Proxy Architecture For Mobile And Peer-To-Peer Networks, Praveena Jayanthi

Computer Science Theses

The growth of wireless telecommunications has stipulated the interest for anywhere-anytime computing. The synergy between networking and mobility will engender new collaborative applications with mobile devices on heterogeneous platforms. One such middleware is “SYSTEM ON MOBILE DEVICES”, SYD developed by the Yamacraw Embedded Systems research team. This type of middleware is an opening step towards Peer-to-Peer mobile networks. This project envisioned collaborative applications among mobile devices and PDAs were used as servers. This thesis studies various existing architectures in mobile computing and their scalability issues. We also proposed new scalable flexible thick client proxy system FTCPS, an architecture suitable for ...


Comparison Of Methods Used For Aligning Protein Sequences, Sangeetha Madangopal Dec 2006

Comparison Of Methods Used For Aligning Protein Sequences, Sangeetha Madangopal

Computer Science Theses

Comparing protein sequences is an essential procedure that has many applications in the field of bioinformatics. The recent advances in computational capabilities and algorithm design, simplified the comparison procedure of protein sequences from several databases. Various algorithms have emerged using state of the art approaches to match protein sequences based on structural and functional properties of the amino acids. The matching involves structural alignment, and this alignment may be global; comprising of the whole length of the protein, or local; comprising of the sub-sequences of the proteins. Families of related proteins are found by clustering sequence alignments. The frequency distributions ...


Toward A Heuristic Model For Evaluating The Complexity Of Computer Security Visualization Interface, Hsiu-Chung Wang Dec 2006

Toward A Heuristic Model For Evaluating The Complexity Of Computer Security Visualization Interface, Hsiu-Chung Wang

Computer Science Theses

Computer security visualization has gained much attention in the research community in the past few years. However, the advancement in security visualization research has been hampered by the lack of standardization in visualization design, centralized datasets, and evaluation methods. We propose a new heuristic model for evaluating the complexity of computer security visualizations. This complexity evaluation method is designed to evaluate the efficiency of performing visual search in security visualizations in terms of measuring critical memory capacity load needed to perform such tasks. Our method is based on research in cognitive psychology along with characteristics found in a majority of ...