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2006

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Use Of Principal Component Analysis With Linear Predictive Features In Developing A Blind Snr Estimation System, Matthew James Marbach Dec 2006

Use Of Principal Component Analysis With Linear Predictive Features In Developing A Blind Snr Estimation System, Matthew James Marbach

Theses and Dissertations

Signal-to-noise ratio is an important concept in electrical communications, as it is a measurable ratio between a given transmitted signal and the inherent background noise of a transmission channel. Currently signal-to-noise ratio testing is primarily performed by using an intrusive method of comparing a corrupted signal to the original signal and giving it a score based on the comparison. However, this technique is inefficient and often impossible for practical use because it requires the original signal for comparison. A speech signal's characteristics and properties could be used to develop a non-intrusive method for determining SNR, or a method that does …


Data Fusion Of Complementary Information From Parietal And Occipital Event Related Potentials For Early Diagnosis Of Alzheimer's Disease, Nicholas Stepenosky Dec 2006

Data Fusion Of Complementary Information From Parietal And Occipital Event Related Potentials For Early Diagnosis Of Alzheimer's Disease, Nicholas Stepenosky

Theses and Dissertations

The number of the elderly population affected by Alzheimer's disease is rapidly rising. The need to find an accurate, inexpensive, and non-intrusive procedure that can be made available to community healthcare providers for the early diagnosis of Alzheimer's disease is becoming an increasingly urgent public health concern. Several recent studies have looked at analyzing electroencephalogram signals through the use of many signal processing techniques. While their methods show great promise, the final outcome of these studies has been largely inconclusive. The inherent difficulty of the problem may be the cause of this outcome, but most likely it is due to …


Random Feature Subspace Ensemble Based Approaches For The Analysis Of Data With Missing Features, Hussein Syed Mohammed Dec 2006

Random Feature Subspace Ensemble Based Approaches For The Analysis Of Data With Missing Features, Hussein Syed Mohammed

Theses and Dissertations

Missing data in real world applications is not an uncommon occurrence. It is not unusual for training, validation or field data to have missing features in some (or even all) of their instances, as bad sensors, failed pixels, malfunctioning equipment, unexpected noise causing signal saturation, data corruption, and so on, are all familiar scenarios in many practical applications.

In this thesis, the feasibility of an ensemble of classifiers trained on a feature subset space is investigated as an effective and practical solution for the missing feature problem. Two ensemble of classifiers approach motivated by the Random Subspace Method are proposed …


Boosted Ensemble Algorithm Strategically Trained For The Incremental Learning Of Unbalanced Data, Michael David Muhlbaier Dec 2006

Boosted Ensemble Algorithm Strategically Trained For The Incremental Learning Of Unbalanced Data, Michael David Muhlbaier

Theses and Dissertations

Many pattern classification problems require a solution that needs to be incrementally updated over a period of time. Incremental learning problems are often complicated by the appearance of new concept classes and unbalanced cardinality in training data. The purpose of this research is to develop an algorithm capable of incrementally learning from severely unbalanced data. This work introduces three novel ensemble based algorithms derived from the incremental learning algorithm, Learn++. Learn++.NC is designed specifically for incrementally learning New Classes through dynamically adjusting the combination weights of the classifiers' decisions. Learn++.UD handles Unbalanced Data through class-conditional voting …


An Architecture For Intelligent Health Assessment Enabled Ieee 1451 Compliant Smart Sensors, Donald Albert Nickles Dec 2006

An Architecture For Intelligent Health Assessment Enabled Ieee 1451 Compliant Smart Sensors, Donald Albert Nickles

Theses and Dissertations

As systems become increasingly complex and costly, potential failure mechanisms and indicators are numerous and difficult to identify, while the cost of loss is very expensive - human lives, replacement units, and impacts to national security. In order to ensure the safety and long-term reliability of vehicles, structures, and devices attention must be directed toward the assessment and management of system health. System health is the key component that links data, information, and knowledge to action. Integrated Systems Health Management (ISHM) doctrine calls for comprehensive real-time health assessment and management of systems where the distillation of raw data into information …


Multiresolution Wavelet Analysis Of Event-Related Eeg Potentials Using Ensemble Of Classifier Data Fusion Techniques For Early Diagnosis Of Alzheimer's Disease, Apostolos Topalis Dec 2006

Multiresolution Wavelet Analysis Of Event-Related Eeg Potentials Using Ensemble Of Classifier Data Fusion Techniques For Early Diagnosis Of Alzheimer's Disease, Apostolos Topalis

Theses and Dissertations

The recent advances and knowledge in medicine and nutrition have greatly improved our average life expectancy. An unfortunate consequence of this longer life span, however, is a dramatic increase in the number of individuals suffering from dementia, and more specifically, from Alzheimer's disease (AD). Furthermore, AD remains under-diagnosed and under-treated until its more severe stages due to lack of standard diagnostic tools available to community clinics. A search for biomarkers that will allow early diagnosis of the disease is therefore necessary to develop effective medical treatments. Such a biomarker should be non-invasive, simple to obtain, safe, inexpensive, accurate, and most …


A "Divide-And-Conquer" Strategy For Nde Signal Inversion In Gas Transmission Pipelines, Justin Gary Bram Dec 2006

A "Divide-And-Conquer" Strategy For Nde Signal Inversion In Gas Transmission Pipelines, Justin Gary Bram

Theses and Dissertations

Signal inversion in nondestructive evaluation (NDE) applications is a critical step before remediation decisions are made. The accuracy and confidence of the signal inversion results therefore play a key role in evaluating the effectiveness of the NDE procedure. Conventional NDE signal inversion algorithms that employ artificial neural networks treat all geometric regions of the NDE signal equally. Consequently, when the inversion algorithm is presented with input data that is significantly different from the training data, the performance of the network deteriorates significantly. This thesis presents a superior alternative for NDE signal inversion. Different geometric regions of the NDE signature are …


Structuring Emperical Methods For Reuse And Efficiency In Product Development Processes, Marshall Edwin Bare Dec 2006

Structuring Emperical Methods For Reuse And Efficiency In Product Development Processes, Marshall Edwin Bare

Theses and Dissertations

Product development requires that engineers have the ability to predict product performance. When product performance involves complex physics and natural phenomena, mathematical models are often insufficient to provide accurate predictions. Engineering companies compensate for this deficiency by testing prototypes to obtain empirical data that can be used in place of predictive models. The purpose of this work is to provide techniques and methods for efficient use of empirical methods in product development processes. Empirical methods involve the design and creation of prototype hardware and the testing of that hardware in controlled environments. Empirical methods represent a complete product development sub-cycle …


Assessing Perceived Marriage Education Needs And Interests Of Latino Individuals In Utah County, Utah, Iliana Snyder Dec 2006

Assessing Perceived Marriage Education Needs And Interests Of Latino Individuals In Utah County, Utah, Iliana Snyder

Theses and Dissertations

This study utilized focus groups to assess the perceived needs and interests for marriage education among single and married Latino individuals residing in Utah County, Utah as well as the identification of common themes and differences for this population. Male and female groups at various points in the marital developmental life stage were studied including high school students (15-18 years of age), single never married young adults (19-30 years of age), committed (engaged or cohabiting) adults, married persons recently transitioning to parenting, and married people with children. The sample consisted of 10 groups, 5 female and 5 male. In addition, …


The Piezoresistive Effect In Microflexures, Gary K. Johns Dec 2006

The Piezoresistive Effect In Microflexures, Gary K. Johns

Theses and Dissertations

The objective of this research is to present a new model for predicting the piezoresistive effect in microflexures experiencing bending stresses. A linear model describing piezoresistivity exists for members in pure tension and compression. Extensions of this model to more complex loading conditions do not match experimental results. An accurate model of piezoresistivity in complex loading conditions would expand the design possibilities of piezoresistive devices. A new model to predict piezoresistive effects in tension, compression, and more complex loading conditions is proposed. The focus of this research is to verify a unidirectional form of this proposed model for microflexures in …


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 …


Statistical Methods For Kinetic Modeling Of Fischer Tropsch Synthesis On A Supported Iron Catalyst, Brian L. Critchfield Dec 2006

Statistical Methods For Kinetic Modeling Of Fischer Tropsch Synthesis On A Supported Iron Catalyst, Brian L. Critchfield

Theses and Dissertations

Fischer-Tropsch Synthesis (FTS) is a promising technology for the production of ultra-clean fuels and chemical feedstocks from biomass, coal, or natural gas. Iron catalysts are ideal for conversion of coal and biomass. However, precipitated iron catalysts used in slurry-bubble column reactors suffer from high attrition resulting in difficulty separating catalysts from product and increased slurry viscosity. Thus, development of an active and selective-supported iron catalyst to manage attrition is needed. This thesis focuses on the development of a supported iron catalyst and kinetic models of FTS on the catalyst using advanced statistical methods for experimental design and analysis. A high …


Branch Detonation Of A Pulse Detonation Engine With Flash Vaporized Jp-8, John David Slack Dec 2006

Branch Detonation Of A Pulse Detonation Engine With Flash Vaporized Jp-8, John David Slack

Theses and Dissertations

Pulse Detonation Engines (PDE) operating on liquid hydrocarbon fuels are limited to operating frequencies of 35 Hz due to long ignition times from a low energy ignition sources. This study shows ignition time of JP-8 can be nearly eliminated by igniting a thrust tube using a secondary detonation. A counter flow heat exchanger attached to a thrust tube utilized waste heat from the detonation process to heat JP-8 to supercritical conditions. The fuel flash vaporized when injected into the air stream of the engine. A detonation was produced by a spark in a 5 cm diameter, 1.37 m long tube. …


Social Withdrawal And Its Behavioral Correlates Among Chinese Preschoolers, Peixia Wu Dec 2006

Social Withdrawal And Its Behavioral Correlates Among Chinese Preschoolers, Peixia Wu

Theses and Dissertations

Researchers have recognized that social withdrawal in early childhood is a complex and multifaceted construct which includes three main observed subtypes: reticence, solitary-passive withdrawal, and solitary-active withdrawal. Each is differentially associated with children's behavioral outcomes in Western societies (e.g., United States, Canada). Furthermore, potential gender differences may exist regarding the distinct associations between non-social behavior and indices of maladjustment across boys and girls due to differential societal and cultural gender-role expectations. Previous studies suggest that subtypes of observed social withdrawal can be identified in Chinese preschoolers. It is important to examine the behavioral correlates of observed withdrawn subtypes in the …


Observation And Tracking Of Tropical Cyclones Using Resolution Enhanced Scatterometry, Richard Ryan Halterman Dec 2006

Observation And Tracking Of Tropical Cyclones Using Resolution Enhanced Scatterometry, Richard Ryan Halterman

Theses and Dissertations

The QuikSCAT scatterometer provides global daily coverage of oceanic near-surface vector winds. Recently, algorithms have been developed to enhance the spatial resolution of QuikSCAT winds from 25~km to 2.5~km posting. These ultra-high resolution winds are used, in comparison with standard L2B data product winds, to observe and track tropical cyclones. Resolution enhanced winds are found to provide additional storm structure such as inner core size and structure and the presence of multiple eyewalls compared with standard resolution winds. The 2.5~km winds are also able to observe storms nearer to the shore than 25~km winds. An analysis of circulation center locatability …


Impact Of Foliar Fungicides On Yield And Net Returns In Soybeans, Benjamin L. Spinks Dec 2006

Impact Of Foliar Fungicides On Yield And Net Returns In Soybeans, Benjamin L. Spinks

Theses and Dissertations

Field studies were conducted in 2003, 2004, and 2005 in the Mississippi delta at 12 locations across common production practices to evaluate the impact of 12 single applications of fungicides at the R3 and R5 growth stage on soybean yield, seed quality, and net returns. Averaged across locations, azoxystrobin alone and mixed with other fungicides increased yields 161 to 343 kg/ha compared to the nontreated control. Fungicide applications made at R3-R4 were more efficacious and resulted in larger yield increases than applications made at R5-R6. Plots treated at the R3-R4 growth stage with 0.11kg ai/ha azoxystrobin alone or in combination …


Clustering Multiple Contextually Related Heterogeneous Datasets, Mahmood Hossain Dec 2006

Clustering Multiple Contextually Related Heterogeneous Datasets, Mahmood Hossain

Theses and Dissertations

Traditional clustering is typically based on a single feature set. In some domains, several feature sets may be available to represent the same objects, but it may not be easy to compute a useful and effective integrated feature set. We hypothesize that clustering individual datasets and then combining them using a suitable ensemble algorithm will yield better quality clusters compared to the individual clustering or clustering based on an integrated feature set. We present two classes of algorithms to address the problem of combining the results of clustering obtained from multiple related datasets where the datasets represent identical or overlapping …


Effects Of Vasoactive Agents On The Mechanical Properties Of Aortic Heart Valve Leaflets, Rebecca Lynn Pounders Mathis Dec 2006

Effects Of Vasoactive Agents On The Mechanical Properties Of Aortic Heart Valve Leaflets, Rebecca Lynn Pounders Mathis

Theses and Dissertations

Heart valve disease is currently one of the leading forms of heart disease. Current literature has shown that endothelin I, angiotension II and 5-HT are vasoactive agents which cause concentration dependent contractions in aortic valve leaflet tissue. This study tested the mechanical properties of leaflets cut in the radial direction after they were exposed to the agents at varied concentrations or for 0.5, 6 or 24 hours. The elastic modulus, ultimate tensile strength and the yield strength were calculated. In the time trials the elastic modulus and the ultimate tensile strength both showed a significant increase at 24-hours. However, there …


Functional Role Of Recombinant Cysteine Protease On Spodoptera Frugiperda Peritrophic Matrix, Srinidi Mohan Dec 2006

Functional Role Of Recombinant Cysteine Protease On Spodoptera Frugiperda Peritrophic Matrix, Srinidi Mohan

Theses and Dissertations

Fall armyworm larvae (FAW), which are serious pests in the southern United States, show retarded growth when they feed on insect-resistant maize inbreds Mp704 and Mp708. These maize genotypes are not only resistant to FAW, but to a number of other lepidopteran pests. In these genotypes, a unique, extracellular, 33-KDa cysteine protease (Mir1-CP) rapidly accumulates in the whorl in response to insect feeding. Initial morphological studies on larvae feeding on resistant maize plants over-expressing the cysteine protease showed severe damage in insect?s first line of defense, the peritrophic matrix (PM). But it is not known whether the cysteine protease has …


Selecting Keyword Search Terms In Computer Forensics Examinations Using Domain Analysis And Modeling, Alfred Christopher Bogen Dec 2006

Selecting Keyword Search Terms In Computer Forensics Examinations Using Domain Analysis And Modeling, Alfred Christopher Bogen

Theses and Dissertations

The motivation for computer forensics research includes the increase in crimes that involve the use of computers, the increasing capacity of digital storage media, a shortage of trained computer forensics technicians, and a lack of computer forensics standard practices. The hypothesis of this dissertation is that domain modeling of the computer forensics case environment can serve as a methodology for selecting keyword search terms and planning forensics examinations. This methodology can increase the quality of forensics examinations without significantly increasing the combined effort of planning and executing keyword searches. The contributions of this dissertation include: ? A computer forensics examination …


Reduction Of Volatile Organic Compounds Emitted During Kiln Drying Of Southern Yellow Pine Lumber, Joseph Martin Dahlen Dec 2006

Reduction Of Volatile Organic Compounds Emitted During Kiln Drying Of Southern Yellow Pine Lumber, Joseph Martin Dahlen

Theses and Dissertations

The objective of the research is to reduce the volatile organic compounds (VOCs) emitted during kiln drying of southern yellow pine (SYP) lumber. Three treatment methods were explored to determine their effect on VOC emissions. The three methods were configured at the air exhaust of a pilot-scale dry kiln. 1) A steel reactor containing copper tubing heated to 100°, 200°, and 240° Celsius was evaluated. Temperature did not statistically affect VOC emissions (p-value = 0.1674). The average reduction of VOCs at 240° C was seven percent. 2) The use of hydrogen peroxide and ultra-violet (UV) light did not reduce VOCs …


Influence Of Food-Grade Ingredients On Offlavor Compounds In Catfish Fillets, Sovann Kin Dec 2006

Influence Of Food-Grade Ingredients On Offlavor Compounds In Catfish Fillets, Sovann Kin

Theses and Dissertations

The purpose of this study was to screen the effect of some food-grade ingredients on the off-odors caused by geosmin and 2-methylisoborneol (MIB) compounds in catfish fillets by sensory evaluation. The study revealed that geosmin and MIB odor intensity were reduced to different degrees when fillets were dipped in lime flavor (94% and 67%, respectively), 0.5% acetic acid (AA) (70% and 16%, respectively), hardwood liquid smoke (98% and 86%, respectively), or hickory liquid smoke (98% and 100% respectively) in cooked products. A 0.5% AA proved to be effective in decreasing odor intensity of geosmin (70%) in cooked products, whereas lime …


Attitudes And Perceptions Of Mississippi Career And Technology School Administrators Toward Technology Integration And Their Knowledge And Use Of The National Educational Technology Standards For School Administators (Nets-A), Janice Holman Sears Dec 2006

Attitudes And Perceptions Of Mississippi Career And Technology School Administrators Toward Technology Integration And Their Knowledge And Use Of The National Educational Technology Standards For School Administators (Nets-A), Janice Holman Sears

Theses and Dissertations

The purpose of this study was to examine Mississippi?s Career and Technology School Administrators? attitudes and perceptions toward technology integration and to determine their knowledge and use of the NETS∙A. The study contributed to the literature on technology integration and the NETS∙A in the secondary classroom. The research design for this study was descriptive and correlational. A pilot study was conducted prior to the commencement of the research study in which no problems were identified. Out of a population of 144 Mississippi Career and Technology School Administrators, 102 participated in the study. A survey instrument consisting of three parts was …


Innovative Scintillating Optical Fibers For Detecting/Monitoring Gamma Radiation, Ashwini Jayaprakash Dec 2006

Innovative Scintillating Optical Fibers For Detecting/Monitoring Gamma Radiation, Ashwini Jayaprakash

Theses and Dissertations

A scintillating optical fiber sensor of this work consists of a scintillating optical fiber, connected to a photomultiplier tube (PMT) via a conventional silica optical fiber. When a gamma ray impinges on the scintillating optical fiber, photons are generated inside the fiber. The photons are trapped inside the fiber and guided through the PMT. The PMT output signal is acquired by a computer. Two types of scintillating optical fibers sensors were developed for gamma ray detection. The first one is a silica optical fiber doped with an inorganic scintillating agent. The second one is a liquid core waveguide optical fiber …


Development Of Power Flow With Distributed Generators And Reconfiguration For Restoration Of Unbalanced Distribution Systems, Sarika Khushalani Dec 2006

Development Of Power Flow With Distributed Generators And Reconfiguration For Restoration Of Unbalanced Distribution Systems, Sarika Khushalani

Theses and Dissertations

With the increasing interest in distribution automation, distribution power flow is important for applications like VAR planning, switching, state estimation and especially optimization. Typically, a distribution system originates at a substation and continues to a lower voltage for delivery to the customers. There are several tools for transmission system analysis. These tools include Newton Raphson, Gauss Seidel and fast decoupled techniques. These techniques however sometimes fail to converge when applied to distribution systems due to their higher resistance/reactance (R/X) ratio of the lines, making them ill conditioned. Distribution systems typically have a radial topological structure where the loads are not …


Study Of Lunar Constellations For Situational Awareness And Surveillance, Devon Sanders Dec 2006

Study Of Lunar Constellations For Situational Awareness And Surveillance, Devon Sanders

Theses and Dissertations

Lunar constellations providing the capabilities of situational awareness and surveillance for future mission operators are analyzed in this study. The use of specialty orbits, such as sun-synchronous and frozen orbits, are analyzed to determine the applicability of these unique orbits. Additionally, altitude and inclination trades are performed to determine the degree to which mission objectives are achieved through ranges of these orbital parameters. Using the analyzed orbits, constellations of varying patterns are developed and surface coverage figures of merit are used to evaluate them. The research concludes with calculation of the yearly cross-track and in-track stationkeeping costs of a representative …


Hybrid Electric Vehicle Modeling In Generic Modeling Environment, Shravana Kumar Musunuri Dec 2006

Hybrid Electric Vehicle Modeling In Generic Modeling Environment, Shravana Kumar Musunuri

Theses and Dissertations

The Hybrid Electric Vehicle (HEV) is a complex electromechanical system with complex interactions among various components. Due to the large number of design variables involved, the design flexibility in the HEV makes performance studies difficult. As the system complexity and sophistication increases, it becomes much more difficult to predict these interactions and design the system accordingly. Also, different variations in the design and manufacture of various components and systems involve a large amount of work and cost to keep updated of all these variations. While the above issues ask for a flexible design environment suitable for vehicle design, most of …


Instructional Choices Of Mississippi Foreign Language Teachers, Elizabeth Anne Harrison Dec 2006

Instructional Choices Of Mississippi Foreign Language Teachers, Elizabeth Anne Harrison

Theses and Dissertations

The purpose of this study was to survey Mississippi foreign language teachers in regards to demographic information pertaining to their educational and professional experiences and how often they employ certain activities taken from the Mississippi Foreign Language Curriculum Framework (2000). The data were then examined to see if a relationship existed between specific teacher demographic data and how they implemented the state-mandated curriculum. A researcher-designed survey instrument was developed. In order to establish the validity and reliability of the instrument two samples were taken: Mississippi foreign language teachers and teachers subscribing to the on-line listserv FLTEACH. A total sample of …


Micro-Chp Modeling And Simulation Using Thermodynamic Cycles, Alan Mark Moran Dec 2006

Micro-Chp Modeling And Simulation Using Thermodynamic Cycles, Alan Mark Moran

Theses and Dissertations

This thesis discusses the thermoeconomic modeling and simulation of micro-CHP systems powered by various prime movers. Micro Cooling, Heating, and Power (micro-CHP) is becoming an increasingly important energy option as the demand for electrical power as well as heating and cooling for buildings increases worldwide. Micro-CHP has the potential to increase the total energy efficiency for cooling, heating, and powering residences, offices, and other relatively small buildings by using waste thermal energy from electricity production to deliver heating and cooling. Calculation methodologies are presented for the different components of micro CHP systems using thermodynamic cycles and mass and energy balances. …


Grout Impregnation Of Pre-Placed Recycled Concrete Pavement (Rcp) For Rapid Repair Of Deteriorated Portland Cement Concrete Airfield Pavements, Travis A. Mann Dec 2006

Grout Impregnation Of Pre-Placed Recycled Concrete Pavement (Rcp) For Rapid Repair Of Deteriorated Portland Cement Concrete Airfield Pavements, Travis A. Mann

Theses and Dissertations

The U.S. military must have the ability to rapidly deploy troops and equipment anywhere in the world as part of a contingency operation. Recent military operations have highlighted the critical need for rapid repair procedures and materials for military use on sub-standard, in-theater airfields. The U.S. Army Corps of Engineers, Engineer Research and Development Center is currently addressing these problems through a program titled ?Joint Rapid Airfield Construction?. This study involves the development of a method using rapid setting grouts and recycled concrete pavement (RCP) to repair portland cement concrete (PCC) pavements. A laboratory study was conducted to evaluate material …