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Theses/Dissertations

2012

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Full-Text Articles in Engineering

Quantification Of Neural Substrates Of Vergence System Via Fmri, Yelda Alkan Dec 2012

Quantification Of Neural Substrates Of Vergence System Via Fmri, Yelda Alkan

Dissertations

Vergence eye movement is one of the oculomotor systems which allow depth perception via disconjugate movement of the eyes. Neuroimaging methods such as functional magnetic resonance imaging (fMRI) measure neural activity changes activity in the brain while subjects perform experimental tasks. A rich body of primate investigations on vergence is already established in the neurophysiology literature; on the other hand, there are a limited number of fMRI studies on neural mechanisms behind the vergence system.

The results demonstrated that vergence system shares neural sources and also shows differentiation within the boundaries of frontal eye fields (FEF) and midbrain of the ...


Dynamic Response Of Highway Bridges Under A Moving Truck And Development Of A Rational Serviceability Requirement, Shabnam Darjani Dec 2012

Dynamic Response Of Highway Bridges Under A Moving Truck And Development Of A Rational Serviceability Requirement, Shabnam Darjani

Dissertations

Through the development and usage of high-strength materials, the design of more flexible bridges is unavoidable. It is assumed that limiting a bridge static deflection would control the excessive vibration caused by more flexible design. However, results of prior studies indicate that deflection limits do not necessarily address bridges vibrational issue.

This dissertation addresses the parameters affecting bridge vibration and provides simple equations to compute bridge dynamic acceleration, velocity and displacement in both transient and steady state parts of the vibration. These equations can then be used to control bridges excessive vibration; and provide human comfort and structural performance.

A ...


Quantification Of Human Motion On Roller Coaster Rides, Chirag Burman Dec 2012

Quantification Of Human Motion On Roller Coaster Rides, Chirag Burman

Theses

Case reports have been published of people experiencing symptoms of traumatic brain injury (TBI) and/or ailments of the vascular tissue around the head. These reports pointed towards G-forces, a scalar measure without a specified direction, which represent the measure of the acceleration of an object divided by acceleration caused by gravity (9.81 m/s2), as a cause of said injuries. Research has been conducted on quantifying the G-forces experienced while on roller coasters, as well as the change in heart rate. However these studies have not been able to show a link between roller-coasters and symptoms.

This ...


Safety Performance Comparison Between Light Rail Transit And Subway, Nehemie Jasmin Dec 2012

Safety Performance Comparison Between Light Rail Transit And Subway, Nehemie Jasmin

Theses

Along with the expansion and addition of guide way transit systems, such as light rail and subway, there came the need to compare the safety performance of each mode. The multimodal transportation systems with many different technologies, operating characteristics and diversified environments made it more difficult to compare their safety.

In order to evaluate the potential for intermodal comparison of safety performance measures, the thesis has focused on the subway and Light Rail Transit (LRT) modes at the national level. Starting with clear definitions of each safety category, the analysis utilizes mostly the National Transit Database (NTD) from recent years ...


Fuzzy Logic For Task Space Telemanipulation Of A Five Fingered Robotic Hand, Raaghavann Srinivasan Dec 2012

Fuzzy Logic For Task Space Telemanipulation Of A Five Fingered Robotic Hand, Raaghavann Srinivasan

Theses

This work presents a fuzzy logic based HandyMan (Hand gesture commands for grasping and manipulation) system to recognize the operator's hand gestures during task space telemanipulation. A combination of joint positions may be shared between at least two manipulation gestures. To avoid misinterpretation of gestures by the gesture recognition system, six new manipulation gestures were introduced. The gestures are produced by the user wearing a CyberGlove™.

This system replaces the previous HandyMan gesture recognition method. The output of the fuzzy system drives the state machines to implement the gestures with the robot hand.

The experimental results show that the ...


Diffuse Axonal Injury Effect On Myelinating Cells And Axons, Jennifer Alison Zalk Dec 2012

Diffuse Axonal Injury Effect On Myelinating Cells And Axons, Jennifer Alison Zalk

Theses

There is no supporting evidence whether myelin degeneration in diffuse axonal injury (DAI) of the white matter is due to death of myelinating oligodendrocytes or secondary axotomy. Cortical neurons are not able to remain healthy in culture to have their axons myelinated. Dorsal root ganglion (DRG) neurons have been shown to be myelinated by cortical oligodendrocytes in culture. An in vitro stretch injury model was used to analyze the DRG axon pathology during and after injury. DRG myelinating Schwann cells are analyzed to demonstrate what is expected from injury to oligodendrocytes. DRG axons demonstrated a high tolerance to stretch ...


13c-Metabolic Flux Analysis Of Soybean Somatic Embryos For Identification Of Metabolic Control Points In Developing Seed, Quyen Xuan Truong Dec 2012

13c-Metabolic Flux Analysis Of Soybean Somatic Embryos For Identification Of Metabolic Control Points In Developing Seed, Quyen Xuan Truong

Graduate Theses and Dissertations

Of the world's major agronomic food crops soybeans rank highest in protein content (~40% Dwt) while also containing significant quantities of oil (~20% Dwt). Based on these unique characteristics soy has become a mainstay in world agriculture, providing a protein source for livestock and human nutrition (68% of global vegetable protein meal consumption in 2011) as well as a primary source of vegetable oil (28% of global vegetable oil consumption in 2011; http://www.soystats.com/2012). The value of soy is therefore found both in its oil and protein content and increasing the content of both is therefore ...


Addressing The Feasibility Of Usi-Based Threads Scheduler On Polymorphic Computing System, Zhang Zhang Dec 2012

Addressing The Feasibility Of Usi-Based Threads Scheduler On Polymorphic Computing System, Zhang Zhang

Graduate Theses and Dissertations

The consistent advances in IC technology result in ever increasing number of transistors. There is more and more interest attracted on the issue of using these transistors in computing more efficiently. The CMP (Chip Multi &ndash processors) is predicted to be one of the most promising solutions for this problem in future. The heterogeneous CMP is supposed to provide more computing efficiency compared to the homogeneous CMP architecture; but it requires complex processing art for manufacturing, which makes it less competitive in the old era. Nowadays, the complicate SOC(System On Chip) manufacturing techniques are pacing fast. This is leading us inexorably to heterogeneous CMP with diverse computing style resources like general purpose CPU, GPU, FPGA, and ASIC cores. In the heterogeneous CMP architecture, the generous purpose CPU provides coverage for all computing ...


Novel Algorithms For Fair Bandwidth Sharing On Counter Rotating Rings, Mete Yilmaz Dec 2012

Novel Algorithms For Fair Bandwidth Sharing On Counter Rotating Rings, Mete Yilmaz

Dissertations

Rings are often preferred technology for networks as ring networks can virtually create fully connected mesh networks efficiently and they are also easy to manage. However, providing fair service to all the stations on the ring is not always easy to achieve.

In order to capitalize on the advantages of ring networks, new buffer insertion techniques, such as Spatial Reuse Protocol (SRP), were introduced in early 2000s. As a result, a new standard known as IEEE 802.17 Resilient Packet Ring was defined in 2004 by the IEEE Resilient Packet Ring (RPR) Working Group. Since then two addenda have been ...


Fabrication And Evaluation Of A Collagen-Based Fiber-Gel Three-Dimensional Construct For Peripheral Nerve Repair, Mevan Lakmal Siriwardane Dec 2012

Fabrication And Evaluation Of A Collagen-Based Fiber-Gel Three-Dimensional Construct For Peripheral Nerve Repair, Mevan Lakmal Siriwardane

Dissertations

Nerve regeneration following a peripheral nerve injury often relies on growth cone- mediated guidance and the presence of Schwann cells to support the regenerating axons and remyelinate portions of denervated nerve pathways. The emphasis of this work is to develop a synthetic nervous tissue construct that contains similar basal lamina or extracellular matrix to peripheral nerve in order to achieve a level of effectiveness in nerve repair and future peripheral nerve regeneration applications. To this end, three- dimensional nervous tissue constructs consisting of type I collagen are fabricated into a composite biomaterial scaffold to promote contact-guided growth of neuronal and ...


Leaching Of Metals And Metalloids From Highway Marking Glass Beads And The Potential Environmental Impact, Nimrat K. Sandhu Dec 2012

Leaching Of Metals And Metalloids From Highway Marking Glass Beads And The Potential Environmental Impact, Nimrat K. Sandhu

Dissertations

Glass beads are embedded in pavement markings to obtain retroreflectivity which plays a crucial role in the lighting-up effect needed for safe driving. Elevated metal and metalloid concentrations of As, Sb, and Pb have recently been observed in imported glass beads. The main objective of this research was to assess the environmental impact associated with applying these imported glass beads in highway markings. To achieve this objective, total metal concentrations were measured using two techniques: hydrofluoric acid digestion followed by inductively coupled plasma mass spectroscopy (HF/ICP-MS), and field portable x-ray fluorescence (FP-XRF) spectroscopy. A number of leaching studies were ...


Driver Injury Severity At U.S. Highway-Rail Crossings, Wei Hao Dec 2012

Driver Injury Severity At U.S. Highway-Rail Crossings, Wei Hao

Dissertations

There are approximately 240,000 highway-rail grade crossings in the United States and highway-rail grade crossing areas have been considered in this study as these are locations where crashes frequently occur. Existing studies on crash models at highway- rail grade crossings can be classified into two categories: accident frequency prediction models and driver injury severity models. Accident frequency prediction at highway-rail grade crossings have been investigated by previous studies using varied statistical models. Few studies, however, have focused on driver injury severity studies. Three drawbacks will be addressed in this research including limitations in traditional highway- rail grade crossings studies ...


Separation Of Various Organic-Organic And Aqueous-Organic Solutions Via Pervaporation, John Tang Dec 2012

Separation Of Various Organic-Organic And Aqueous-Organic Solutions Via Pervaporation, John Tang

Dissertations

Pervaporation, an energy saving separation process, can be useful in pharmaceutical processing. However, the organic solvents involved in pharmaceutical product synthesis are chemically demanding; very few polymers are able to withstand them. An ideal membrane would be polymeric having a high thermal, chemical and mechanical stability. Such a membrane is made of a copolymer of polydimethyldioxole and tetrafluoroethylene known as PDD-TFE of the CMS-3 variety with a very high free volume. This novel membrane is used to separate a variety of organic-organic and aqueous-organic mixtures. An earlier study based on water-ethanol-isopropanol has shown evidence that the membrane selectivity may be ...


Particle Engineering Via Surface Modification During Micronization For Pharmaceutical Applications, Xi Han Dec 2012

Particle Engineering Via Surface Modification During Micronization For Pharmaceutical Applications, Xi Han

Dissertations

Improving the dissolution rate of Biopharmaceutics Classification System (BCS) class II drugs is an important research area. Micronization which can increase the specific surface area is a promising method to improve the dissolution rate. Micronization alone, however, can lead to downstream processing problems related to poor flow and dispersion properties. The importance of the flowability of pharmaceutical powders is well-documented in the literature. It is, therefore, important to develop a method that can simultaneously overcome these processing issues and allow for micronizing the API. In this work, dry particle coating technique is investigated in the context of micronizing API powders ...


Mathematical Modeling Of Heavy Metals Diffusion And Removal From Cylindrical Cement Forms Coated With Bio-Film, Mojdeh Tabatabaie Dec 2012

Mathematical Modeling Of Heavy Metals Diffusion And Removal From Cylindrical Cement Forms Coated With Bio-Film, Mojdeh Tabatabaie

Dissertations

A mathematical model is developed to predict bioleachi ng of heavy metals from long cylindrical shape cementitious samples. In this model, the metal concentration difference within the solid and its surface is considered as the main driving force for transport of metals to the surface of a sample at a given temperature and pressure. Fick’s first and second law are applied to explain the motion of contaminants in a long and uniform cylindrical solid. In addition, the model considers Michaelis-Menten type kinetics, a special case of the widely accepted Langmuir-Hinshelwood reaction mechanism, at the surface of the encapsulating cylinder ...


Radar Based Navigation In Unknown Terrain, Kyle J. Kauffman Dec 2012

Radar Based Navigation In Unknown Terrain, Kyle J. Kauffman

Theses and Dissertations

There is a great need to develop non-GPS based methods for positioning and navigation in situations where GPS is not available. This research focuses on the development of an Ultra-Wideband Orthogonal Frequency Division Multiplexed (UWB-OFDM) radar as a navigation sensor in GPS-denied environments. A side-looking vehicle-fixed UWB-OFDM radar is mounted to a ground or aerial vehicle continuously collecting data. A set of signal processing algorithms and methods are developed which use the raw radar data to aide in calculating the vehicle position and velocity via a simultaneous localization and mapping (SLAM) approach. The radar processing algorithms detect strong, persistent, and ...


A Nonparametric Approach To Segmentation Of Ladar Images, Eric A. Buschelman Dec 2012

A Nonparametric Approach To Segmentation Of Ladar Images, Eric A. Buschelman

Theses and Dissertations

The advent of advanced laser radar (ladar) systems that record full-waveform signal data has inspired numerous inquisitions which aspire to extract additional, previously unavailable, information about the illuminated scene from the collected data. The quality of the information, however, is often related to the limitations of the ladar camera used to collect the data. This research project uses full-waveform analysis of ladar signals, and basic principles of optics, to propose a new formulation for an accepted signal model. A new waveform model taking into account backscatter reflectance is the key to overcoming specific deficiencies of the ladar camera at hand ...


Exploitation Of Rf-Dna For Device Classification And Verification Using Grlvqi Processing, Donald R. Reising Dec 2012

Exploitation Of Rf-Dna For Device Classification And Verification Using Grlvqi Processing, Donald R. Reising

Theses and Dissertations

This dissertation introduces a GRLVQI classifier into an RF-DNA fingerprinting process and demonstrates applicability for device classification and ID verification. Unlike MDA/ML processing, GRLVQI provides a measure of feature relevance that enables Dimensional Reduction Analysis (DRA) to enhance the experimental-to-operational transition potential of RF-DNA fingerprinting. Using 2D Gabor Transform RF-DNA fingerprints extracted from experimentally collected OFDM-based 802.16 WiMAX and 802.11 WiFi device emissions, average GRLVQI classification accuracy of %C greater than or equal to 90% is achieved using full and reduced dimensional feature sets at SNR greater than or equal to 10.0 dB and SNR greater ...


Condition-Dependent Risk Assessment Of Large-Scale Grid-Tied Photovoltaic Power Systems, Sherwin Li Dec 2012

Condition-Dependent Risk Assessment Of Large-Scale Grid-Tied Photovoltaic Power Systems, Sherwin Li

Master's Theses

This thesis reviews the methods for evaluating the reliability of large PV systems and techniques for quantifying the impacts of PV interconnection on distribution system reliability. In addition, a comparative study is performed to evaluate the seasonal condition-dependent risk performance of central-inverter and string-inverter grid-tied PV power systems. Major contributions include: 1) risk analysis of seasonal impacts for string and centralized PV systems. Seasonal sensitivities of PV system risks to system structures, temperature variation, solar insolation, and capacitor equivalent series resistance are analyzed; and 2) the incorporation of the effect of operational conditions and the aging failure model into the ...


Modeling And Characterization Of Power Distribution Networks With Installed Distributed Generation And Connected Phevs, Santhosh Basineni Dec 2012

Modeling And Characterization Of Power Distribution Networks With Installed Distributed Generation And Connected Phevs, Santhosh Basineni

Electrical Engineering Theses

This thesis is focused on the modeling and characterization of power distribution networks with installed distributed generation and connected plug-in hybrid electric vehicles (PHEV). A PHEV charging/discharging (bidirectional) model has been developed in MATLAB®-Simulink. Installed photovoltaic systems with varying irradiance rates are modeled and characterized. Moreover, installed wind generators with varying wind speeds are modeled and characterized. Furthermore, the charging and discharging characteristics of connected PHEV are determined. The system characteristics are determined and investigated against the PHEV battery state of charge (SOC).


Use Of International Hydrographic Organization Tidal Data For Improved Tidal Prediction, Songwei Qi Dec 2012

Use Of International Hydrographic Organization Tidal Data For Improved Tidal Prediction, Songwei Qi

Dissertations and Theses

Tides are the rise and fall of water level caused by gravitational forces exerted by the sun, moon and earth. Understanding sea level variation and its impact currents is very important especially in coastal regions. With knowledge of the tide-generating force and boundary conditions, hydrodynamic models can be used to predict or model tides in coastal regions. However, these models are not sufficiently accurate, and in-situ tide gauge data may be used to improve them in coastal regions. The International Hydrographic Organization (IHO) tidal data bank consists of over 4000 tide gauge stations scattered all around the globe, most of ...


Modeling The Effects Of The Local Environment On A Received Gnss Signal, Marshall E. Haker Dec 2012

Modeling The Effects Of The Local Environment On A Received Gnss Signal, Marshall E. Haker

Theses and Dissertations

There is an ongoing need in the GNSS community for the development of high-fidelity simulators which generate data that replicates what can truly be expected from a challenging environment such as an urban canyon or an indoor environment. The algorithm developed for use in the research in this dissertation, the Signal Decomposition and Parameterization Algorithm (SDPA), is presented in order to respond to this need. This algorithm is designed to decompose a signal received using a GNSS recording and playback system and output parameters that can be used to reconstruct the effects on the signal of the environment local to ...


Game Theory Approach To Transportation Network Vulnerability Measurement, Qixing Wang Dec 2012

Game Theory Approach To Transportation Network Vulnerability Measurement, Qixing Wang

Master's Theses

The vulnerability of a transportation network is strongly correlated with the ability of the network to withstand shocks and disruptions. A robust network with strategic redundancy allows for the redistribution or reassignment of traffic without unduly compromising system performance. As such, high-volume edges with limited alternative paths represent system vulnerabilities – a feature of transportation networks that has been exploited in the past to identify critical components. In this thesis, a mixed-strategy, two opponents, non-zero sum, combinatorial game theoretical framework are presented for measuring network vulnerability. Two solution approaches (Shortest Path Algorithm with Entropy function (SPE) & User Equilibrium Assignment with Interest ...


Effect Of Liquid-Solid Contact On Thermal Cracking Of Heavy Hydrocarbons In A Mechanically Fluidized Reactor, Mitesh C. Chaudhari Dec 2012

Effect Of Liquid-Solid Contact On Thermal Cracking Of Heavy Hydrocarbons In A Mechanically Fluidized Reactor, Mitesh C. Chaudhari

Electronic Thesis and Dissertation Repository

The aim of the thesis was to study the effect of liquid-solid contact on the thermal cracking of heavy hydrocarbons carried out in Fluid Cokers. The research has been carried out using a Mechanically Fluidized Reactor (MFR) in which the operating conditions of the Fluid CokingTM reactions can be simulated and monitored. The first part of the research, aimed at investigating the effect of agitation on liquid-solid contact, which was carried out by changing the rotation speed of the agitator of the MFR for both non-reactive as well as for reactive systems. In both situations, it was observed that ...


Automatic Assessment Of Cardiac Left Ventricular Function Via Magnetic Resonance Images, Mariam Afshin Dec 2012

Automatic Assessment Of Cardiac Left Ventricular Function Via Magnetic Resonance Images, Mariam Afshin

Electronic Thesis and Dissertation Repository

Automating global and segmental (regional) assessments of cardiac Left Ventricle (LV) function in Magnetic Resonance Images (MRI) has recently sparked an impressive research effort, which has resulted a number of techniques delivering promising performances. However, despite such an effort, the problem is still acknowledged to be challenging, with substantial room for improvements in regard to accuracy. Furthermore, most of the existing techniques are labour intensive, requiring delineations of the endo- and/or epi-cardial boundaries in all frames of a cardiac sequence.

On the one hand, global assessments of LV function focus on estimation of the Ejection Fraction (EF), which quantifies ...


Near-Wake Flow Dynamics Of A Horizontal Axis Wind Turbine, Pooyan Hashemi Tari Dec 2012

Near-Wake Flow Dynamics Of A Horizontal Axis Wind Turbine, Pooyan Hashemi Tari

Electronic Thesis and Dissertation Repository

Experiments have been conducted in a large wind tunnel set-up in order to study the flow structures within the near-wake region of a horizontal axis wind turbine. Particle Image Velocimetry (PIV) has been employed to quantify the mean and turbulent components of the flow field. The measurements have been performed in multiple adjacent horizontal planes in order to cover the area behind the rotor in a large radial interval, at several locations downstream of the rotor. The measurements were phase-locked in order to facilitate the re-construction of the three-dimensional flow field. Acquiring uniform particle distribution in the measurement planes as ...


Properties And Applications Of Sensory Outcome Measures In Carpal Tunnel Syndrome, Derek Km Cheung Dec 2012

Properties And Applications Of Sensory Outcome Measures In Carpal Tunnel Syndrome, Derek Km Cheung

Electronic Thesis and Dissertation Repository

This thesis aimed to determine the psychometric properties and applications of sensory threshold tools and outcome measures in patients with Carpal Tunnel Syndrome (CTS). The first chapter is a psychometric study that defines clinically important difference (CID), construct validity and responsiveness of touch and vibration threshold tools and in the Symptoms Severity Scale (SSS). The study found the CID for the PSSD and for the SSS was 0.15g/mm2 and 0.50 respectively. The study also found that the Vibrometer was more representative of hand function and responsive compared PSSD. The second objective of this thesis was to ...


Weather-Based Damage Prediction Models For Electric Distribution Networks, David W. Wanik Dec 2012

Weather-Based Damage Prediction Models For Electric Distribution Networks, David W. Wanik

Master's Theses

From thunderstorms to hurricanes, electric distribution networks are subject to a wide range of warm weather storm events. Tropical Storm Irene (2011) and Hurricane Sandy (2012) are two events in recent memory that disrupted over half of The Connecticut Light and Power Company’s (CL&P) service territory, which left some customers without power for up to eleven days. This research study investigates a damage prediction framework for both thunderstorms and hurricanes that combines two generalized linear models to probabilistically determine the occurrence and extent of damages, known as trouble spots, to the overhead power distribution network. The models are ...


A Depolymerization Based Model Of Neuron Growth Cone Shape And Motility, Neerajha Nagarajan Dec 2012

A Depolymerization Based Model Of Neuron Growth Cone Shape And Motility, Neerajha Nagarajan

Master's Theses

Cell migration is a ubiquitous process underlying critical biological mechanisms like wound healing, cancer metastasis and even neuron growth cone motility. It is a critical process for the living organisms as it ensures proper functioning of the system, for example, crawling fibroblasts endure closure of wounds during wound healing. Here we focus our interest on neuron growth cones, a sensory and motile organelle present at the tip of extending neurites, like the axons, in neurons. These are responsible for neuron pathfinding onto specific targets and synapses, in responses to various guidance cues. Interestingly, the motility of the growth cones is ...


Analysis Of The Enzymatic Decomposition Of Barley Starch To Simple Carbohydrates, Mark Mathiew Williams Dec 2012

Analysis Of The Enzymatic Decomposition Of Barley Starch To Simple Carbohydrates, Mark Mathiew Williams

Master's Theses

The decomposition of barley starch plays a fundamental role in the final quality of fermented beverages in the brewing industry. The process of mashing involves steeping milled barley in water to stimulate the enzymatic decomposition of starch into simple carbohydrates. The temperature of the water significantly impacts the activity of the enzymes and in turn the resulting concentrations of sugar products. A kinetic model accurately predicting the types and quantities of sugars formed as a function of mash temperature would serve as a tool to tailor sugar profiles and optimize mashing procedures for a desired product.

Sixty minutes mashes were ...