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Pitch-Based Activated Carbon Fibers: The Effect Of Precursor Composition On Pore Structure, Halil Tekinalp Dec 2011

Pitch-Based Activated Carbon Fibers: The Effect Of Precursor Composition On Pore Structure, Halil Tekinalp

All Dissertations

Although researchers have previously investigated the effect of precursor differences on the final properties of activated carbon fibers (ACFs), those precursors were not well-characterized. In particular, detailed information about their molecular composition and anisotropy was not available.
In this study, seven oligomeric fractions, each of well-defined composition and molecular weight (mol wt) distribution, were isolated from a commercially produced isotropic petroleum pitch (i.e., Marathon M–50) and used for the production of ACFs. Four of these precursors of varying oligomeric composition were fully isotropic and three contained different levels of mesophase, so that the effects of molecular composition and molecular order …

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Fractal Jackson Networks, Mahmoud Rezaei Dec 2011

Fractal Jackson Networks, Mahmoud Rezaei

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In this dissertation, Gaussian random measures that arise as limits of Jackson networks. The support of the random measure is a fractal having Hausdorff dimension delta . The variance measure is the Hausdorff measure also of dimension delta.

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Electrical Detection Of Mechanical Resonance In Nanotubes And Semiconducting Nanowires, Doyl Dickel Dec 2011

Electrical Detection Of Mechanical Resonance In Nanotubes And Semiconducting Nanowires, Doyl Dickel

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In recent years, there has been substantial interest in the development of microelectro-mechanical systems (MEMS) and even nanoelectro-mechanical systems (NEMS) for use in a wide variety of applications both as experimental tools (refs) and in a continuing effort to decrease the size and cost and increase the efficiency of electrical components. In particular, cantilevered nanometer beams have been a recent focus due to a number of interesting properties, including enhanced field emission, high tensile strength, and piezoelectric properties. The ability to accurately determine the electrical and mechanical properties of these cantilevers is paramount in assessing their feasibility as MEMS and …

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Single Particle And Ensemble Spectroscopy Of Conjugated Polymer Nanoparticles And Their Development For Photodynamic Therapy, Jennifer Grimland Dec 2011

Single Particle And Ensemble Spectroscopy Of Conjugated Polymer Nanoparticles And Their Development For Photodynamic Therapy, Jennifer Grimland

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Energy transport in conjugated polymers is the combination of energy transfer and exciton diffusion. There is considerable ongoing research in this field, converging to develop better organic photovoltaics, polymer light emitting diodes (PLEDs) and organic solar cells, to name a few. One way these phenomena can be explored is by doing solution dependent studies on conjugated polymer nanoparticles. With experiments on CP dots in an aqueous solution and the addition of a water miscible organic solvent in varying concentrations, dynamics occurring in the folding process can be better understood, and also exciton and fluorescence quenching properties can be extracted as …

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Temporal Pier Scour Evolution Under Stepped Hydrographs, Mark Schillinger Dec 2011

Temporal Pier Scour Evolution Under Stepped Hydrographs, Mark Schillinger

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The present study was aimed at measuring the scour hole profile at bridge piers under clear water scour. Scour tests were performed under both steady state flow and under stepped hydrographs. Multiple smaller flood events were run to determine how flood history affects scour hole development. Various equilibrium scour depth equations and proposed temporal scour models were compared. The similarity of the scour hole profiles with time and flow history were evaluated.
Experiments were conducted in a 14.8 m long, 1.19 m wide, 1.22 m deep rectangular flume with a model bridge pier. A uniform sediment bed (d50= …

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A New Approach To Dynamic Modeling Of Continuum Robots, Nivedhitha Giri Dec 2011

A New Approach To Dynamic Modeling Of Continuum Robots, Nivedhitha Giri

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ABSTRACT
In this thesis, a new approach for developing practically realizable dynamic models for continuum robots is proposed. Based on the new dynamic models developed, a novel technique for analyzing the capabilities of continuum manipulators to be employed in various real world applications has also been proposed and developed.
A section of a continuum arm is modeled using lumped model elements (masses, springs and dampers). It is shown that this model, although an approximation to a continuum structure, can be used to conveniently analyze the dynamics of the arm with suitable tradeoff in accuracy of modeling. This relatively simple model …

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An Early Warning Monitoring System For Cnc Spindle Bearing Failure, Andrew Werner Dec 2011

An Early Warning Monitoring System For Cnc Spindle Bearing Failure, Andrew Werner

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Equipment employed in a manufacturing environment must be able to operate as long as possible having as little downtime as possible. Therefore, maintenance is crucial in order to allow for the equipment to perform its designated tasks without failure, especially on critical systems. In a CNC machine, if the spindle fails, the machine is useless. Having the ability to detect spindle degradation to the point where a replacement spindle installation can be planned, via condition monitoring, is invaluable to a manufacturer who utilizes these types of machines.
An early warning monitoring system for CNC spindle bearing failure has been developed …

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Short Remarks On The Political And Social Writings Of Reverend Anthony Walke Of Princess Anne County, Virginia & A Concise & Impartial Account Of The Causes Of Their Origins & Progress, Roberta Vogt Dec 2011

Short Remarks On The Political And Social Writings Of Reverend Anthony Walke Of Princess Anne County, Virginia & A Concise & Impartial Account Of The Causes Of Their Origins & Progress, Roberta Vogt

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The following thesis examines multiple social and political topics in the largely unstudied writings of Reverend Anthony Walke (c. 1755-1814) of Princess Anne County, Virginia. His papers reside at the Filson Historical Society in Louisville, Kentucky, as well as appearing in Virginia newspapers of the period. Walke's works comprise more than four hundred pages of primary source documents that relate to late eighteenth-century Virginia, and span the period of 1786 through 1805.
My research emphasizes his Revolutionary War pamphlet, Remarkable Occurrences during the unhappy American War, & a concise & impartial Account of the Causes of its Origin & Progress: …

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Relating Land Cover And Channel Morphology To Stream Flow Function In The Lower Pee Dee Watershed, South Carolina, Zachary Smoot Dec 2011

Relating Land Cover And Channel Morphology To Stream Flow Function In The Lower Pee Dee Watershed, South Carolina, Zachary Smoot

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The South Carolina Pee Dee Project (SCPDP) aims to develop a method for the determination of Minimum Allowable Flows (MAFs) in streams in the Pee Dee region. This study is a portion of the larger SCPDP, focusing primarily upon analyses of geomorphic and hydrologic processes, as well as landscape and habitat analyses. Specific objectives include: 1) To distinguish the effect of various land cover classes and scales of analyses on components of stream flow function; 2) To determine trends in hydraulic geometry (regional curves) for the SCPDP region; and 3) To determine what measures of stream flow function, stream geomorphology, …

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Robust Design And Monitoring Tools For Sustainable And Resilient Structural Design And Infrastructure Management, Sarah Dalton Dec 2011

Robust Design And Monitoring Tools For Sustainable And Resilient Structural Design And Infrastructure Management, Sarah Dalton

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Structural systems are subject to inherent uncertainties due to the variability in many hard-to-control `noise factors' that include but are not limited to external loads, material properties, and construction workmanship. Two design methodologies have been widely accepted in the practicing engineering realm to manage the variability associated with operational structures: Allowable Stress Design (ASD) and Load and Resistance Factor Design (LRFD). These traditional approaches explicitly recognize the presence of uncertainty; however, they do not take robustness against this uncertainty into consideration. Overlooking this robustness against uncertainty in the structural design process has two drawbacks. First, the design may not satisfy …

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Data-Intensive Computing For Bioinformatics Using Virtualization Technologies And Hpc Infrastructures, Pengfei Xuan Dec 2011

Data-Intensive Computing For Bioinformatics Using Virtualization Technologies And Hpc Infrastructures, Pengfei Xuan

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The bioinformatics applications often involve many computational components and massive data sets, which are very difficult to be deployed on a single computing machine. In this thesis, we designed a data-intensive computing platform for bioinformatics applications using virtualization technologies and high performance computing (HPC) infrastructures with the concept of multi-tier architecture, which can seamlessly integrate the web user interface (presentation tier), scientific workflow (logic tier) and computing infrastructure (data/computing tier). We demonstrated our platform on two bioinformatics projects. First, we redesigned and deployed the cotton marker database (CMD) (http://www.cottonmarker.org), a centralized web portal in the cotton research community, using the …

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Effect Of Selected Phase Change Materials Concentration And Manufacturing Process On The Properties Of Plaster Mixture Systems, Rong Cui Dec 2011

Effect Of Selected Phase Change Materials Concentration And Manufacturing Process On The Properties Of Plaster Mixture Systems, Rong Cui

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Phase change materials (PCM) are generally used in building construction materials for their ability to absorb and release large amounts of energy when their phase change happens at their specific melting temperature. This results in a significant increase in thermal mass of the building, a reduction in temperature fluctuations and therefore a reduction in heating and cooling loads. However, in order to properly select a PCM and optimize its integration in a specific building, the properties of building construction materials enhanced with PCM must be known. This research focuses on studying the effects of the concentration of a micro-encapsulated PCM …

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Fabrication And Characterization Of Multi-Functional Non-Spherical Particles Via Mechanical Deformation, Venkata Shilpa Varahagiri Dec 2011

Fabrication And Characterization Of Multi-Functional Non-Spherical Particles Via Mechanical Deformation, Venkata Shilpa Varahagiri

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Nanoparticles bridge the gap between bulk materials and molecules. They possess exciting but contrasting mechanical, chemical, magnetic and optical properties when compared to their bulk counterparts due to their shape and size. When the size of noble metal nanoparticles is reduced to less than the wavelength of light, the particles intensely absorb and scatter light at wavelengths that depend on the particle size, shape, and local dielectric environment due to Localized Surface Plasmon Resonance (LSPR) modes. Recently, plasmonic particles have been used in a wide variety of sensor and optical device applications including immunoassays and surface enhanced Raman spectroscopy substrates. …

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Influence Of Pavement Type On Near Surface Air Temperature, David Duncan Dec 2011

Influence Of Pavement Type On Near Surface Air Temperature, David Duncan

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Effects from an Urban Heat Island (UHI) can be detrimental to the world as a whole. This study examines a collection of permeable and conventional pavements in South Carolina to determine how they relate to near surface air temperatures, which is an indicator of the UHI impact of an area. Three locations were used, each with a different selection of pavement type. Permeable and conventional forms of both asphalt and concrete were tested, as were some open graded friction course samples. Air temperatures were measured and recorded from the pavement surface up to an elevation of 60-in.
Multiple days of …

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A Comparison Of The Performance Of Neural Q-Learning And Soar-Rl On A Derivative Of The Block Design (Bd)/Block Design Multiple Choice (Bdmc) Subtests On The Wisc-Iv Intelligence Test, Charreau Bell Dec 2011

A Comparison Of The Performance Of Neural Q-Learning And Soar-Rl On A Derivative Of The Block Design (Bd)/Block Design Multiple Choice (Bdmc) Subtests On The Wisc-Iv Intelligence Test, Charreau Bell

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Teaching an autonomous agent to perform tasks that are simple to humans can be complex, especially when the task requires successive steps, has a low likelihood of successful completion with a brute force approach, and when the solution space is too large or too complex to be explicitly encoded. Reinforcement learning algorithms are particularly suited to such situations, and are based on rewards that help the agent to find the optimal action to execute given a certain state. The task investigated in this thesis is a modified form of the Block Design (BD) and Block Design Multiple Choice (BDMC) subtests, …

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Rigging And Texturing Considerations For The Short Film Spider Fight, Casey Johnson Dec 2011

Rigging And Texturing Considerations For The Short Film Spider Fight, Casey Johnson

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This paper delves into two separate production areas of the short film, Spider Fight: the approach used to solve the problem of rigging eyelids for 3d characters, and the pipelines that were implemented for texturing 3d assets. Typically, problems exist in the rigging of eyelids for 3d characters. Productions rely on a series of blend shapes, or a combination of joints and blend shapes, to produce satisfactory eyelid movement. Spider Fight, however, used a series of curves and joints to control the movement of the eyelids, which allowed a high degree of control over eyelid movement, and also fast editing …

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A Comparison And Evaluation Of Three Different Pose Estimation Algorithms In Detecting Low Texture Manufactured Objects, Robert Kriener Dec 2011

A Comparison And Evaluation Of Three Different Pose Estimation Algorithms In Detecting Low Texture Manufactured Objects, Robert Kriener

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This thesis examines the problem of pose estimation, which is the problem of determining the pose of an object in some coordinate system. Pose refers to the object's position and orientation in the coordinate system. In particular, this thesis examines pose estimation techniques using either monocular or binocular vision systems.
Generally, when trying to find the pose of an object the objective is to generate a set of matching features, which may be points or lines, between a model of the object and the current image of the object. These matches can then be used to determine the pose of …

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Parallel Implementation Of The Singular Value Decomposition Using Opencl, Bhushan Rayrikar Dec 2011

Parallel Implementation Of The Singular Value Decomposition Using Opencl, Bhushan Rayrikar

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General-Purpose Graphics Processing Units (GPGPUs) have massively parallel computational capabilities. Low cost and ease of programming make them a popular choice over other parallel architectures such as large clusters and accelerators such as Field-Programmable Gate Arrays (FPGAs). Mature programming frameworks for GPGPUs, such as CUDA from Nvidia and OpenCL from the Khronos Group, reduce the learning curve and development time for programming GPGPU architectures. OpenCL, a relatively new industry standard for parallel computing makes it possible to write a single program for heterogeneous platforms that is portable across multiple platforms including GPGPUs and multi-core processors with minimal coding modifications.
GPGPU …

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Investigation Of A Novel Method For Polonium-210 Determination In Groundwater, Tara Matheny Dec 2011

Investigation Of A Novel Method For Polonium-210 Determination In Groundwater, Tara Matheny

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A novel method was investigated for the quantification of 210Po in water as an alternative to the standard method of spontaneous plating onto Ag disks followed by quantification with an alpha spectrometer. The novel method concentrated a 0.5L sample by MnO2 co-precipitation followed by dissolution of the precipitate into a solution. Polonium-210 was separated from the solution and quantified in a column containing a 50:50 by volume mixture of Pb resin (Eichrom Technologies, Inc.) mixed with granulated CaF2:Eu scintillator. The column containing 210Po is quantified on a liquid scintillation counter without the introduction of liquid cocktail. The minimum detectable concentration …

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Influence Of Warm Mix Additives Upon High Rap Asphalt Mixes, William Rogers Dec 2011

Influence Of Warm Mix Additives Upon High Rap Asphalt Mixes, William Rogers

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This study was conducted to determine the effect of warm mix (WMA) modifiers on asphalt mixes containing high percentages of reclaimed asphalt pavement (RAP). Mixes were created using three aggregate sources, four RAP percentages (0%, 20%, 35%, and 50%), and three warm mix modifiers (HMA, zeolite, and Sasobit®). Base binders from the same source (PG 64 -22, 58 -28, 52 -28) and one rejuvenator were used for each mix to ensure the final blended binder grade was at least PG 64 -10.
Specimens were created at HMA or suggested WMA temperatures and tested for rut depth, indirect tensile strength (ITS), …

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Performance Analysis And Fitness Of Gpgpu And Multicore Architectures For Scientific Applications, Mohammad Bhuiyan Dec 2011

Performance Analysis And Fitness Of Gpgpu And Multicore Architectures For Scientific Applications, Mohammad Bhuiyan

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Recent trends in computing architecture development have focused on exploiting task- and data-level parallelism from applications. Major hardware vendors are experimenting with novel parallel architectures, such as the Many Integrated Core (MIC) from Intel that integrates 50 or more x86 processors on a single chip, the Accelerated Processing Unit from AMD that integrates a multicore x86 processor with a graphical processing unit (GPU), and many other initiatives from other hardware vendors that are underway.
Therefore, various types of architectures are available to developers for accelerating an application. A performance model that predicts the suitability of the architecture for accelerating an …

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Electrolyte Incorporation Into Composite Electrodes For Proton-Exchange Membrane Fuel Cells And Lithium-Ion Batteries, Jung Oh Dec 2011

Electrolyte Incorporation Into Composite Electrodes For Proton-Exchange Membrane Fuel Cells And Lithium-Ion Batteries, Jung Oh

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This dissertation describes research on the preparation and characterization of composite electrodes for use in proton-exchange membrane (PEM) fuel cells and lithium ion batteries. The general focus of the research was on high-surface-area carbon supports for platinum catalysts in fuel cells, and integration of electrolytes, particularly fluoropolymer electrolytes, into composite electrodes both batteries and fuel cells. Results are described for work in the following three specific topical areas.
1. Carbon nanofibers for use as platinum (Pt) catalyst supports in fuel cells were prepared by carbonization of electrospun acrylic fibers. The resulting carbon nanofibers were found to contain mainly micropores. Following …

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Effect Of Relative Humidity And Temperature Control On In-Cabin Thermal Comfort State, Ali Alahmer Dec 2011

Effect Of Relative Humidity And Temperature Control On In-Cabin Thermal Comfort State, Ali Alahmer

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This dissertation discusses the effect of manipulating the relative humidity RH levels inside vehicular cabins on the thermal comfort and human occupants' thermal sensation. Three different techniques are used to investigate this effect. Firstly, thermodynamic and psychometric analyses are used to incorporate the effect of changing RH along with the dry bulb temperature on the human comfort window. Specifically, the study computes the effect of changing the relative humidity on the amount of heat rejected from the passenger compartment and the effect on occupants comfort zone. A practical system implementation is also discussed in terms of an evaporative cooler design. …

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Fabrication Of Grooved Hollow Fiber Membrane For Nerve Regeneration: Process Modeling And Performance Evaluation, Jun Yin Dec 2011

Fabrication Of Grooved Hollow Fiber Membrane For Nerve Regeneration: Process Modeling And Performance Evaluation, Jun Yin

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Nerve injury is a general but intractable disease in traumatic injuries, leading to a significant reduction of functions in the nervous system. Extensive efforts are made on nerve injury rehabilitation. Since the appropriate connections between neurons and their targets are necessary, guiding axonal outgrowth is an essential step for neuron outgrowth in nervous system development, functioning, and regeneration. Besides the direct surgical nerve connection, an artificial means of guiding nerve regeneration called nerve conduits is widely applied in nerve injury rehabilitation. The main function of nerve conduits is to bridge the nerve gap, to help regenerating axons across damaged regions …

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Time-Interval Analysis For Radiation Monitoring, Peng Luo Dec 2011

Time-Interval Analysis For Radiation Monitoring, Peng Luo

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On-line radiation monitoring is essential to the U.S. Department of Energy (DOE) Environmental Management Science Program for assessing the impact of contaminated media at DOE sites. The goal of on-line radiation monitoring is to quickly detect small or abrupt changes in activity levels in the presence of a significant ambient background. The focus of this research is on developing effective statistical algorithms to meet the goal of on-line monitoring based on time-interval (time-difference between two consecutive radiation pulses) data. Compared to the more commonly used count data which are registered in a fixed count time, time-interval data possess the potential …

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The Toxicity Of Carbon Nanotubes To Daphnia Magna, Aaron Edgington Dec 2011

The Toxicity Of Carbon Nanotubes To Daphnia Magna, Aaron Edgington

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A particle is classified as nano in size if it has at least one dimension less than 100 nm which gives them chemical and physical characteristics that are different from the bulk material. Over the last twenty years nanotechnology has exploded as an industry. It has been estimated that there are 1000 consumer products on the market today that contain nanomaterials and 2 million jobs worldwide will be devoted directly to nanotechnology research, development, and product manufacturing by 2015. Carbon nanotubes (CNTs) can be visualized as sheets of graphene rolled into a cylinder. Carbon nanotubes small diameter (nanometer scale) and …

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Thermal Inactivation Of Stress Adapted Pathogens In Compost, Randhir Singh Dec 2011

Thermal Inactivation Of Stress Adapted Pathogens In Compost, Randhir Singh

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In the United States, 1.3 billion tons of animal wastes are produced annually. Disposal of this huge amount of waste on agricultural land without proper treatment is a public health safety issue as animal waste is a potential source of several human pathogens. Therefore, composting of animal wastes is an economical solution to this problem. The high temperature reached during this process also brings about inactivation of pathogens in the waste. However, survival of pathogens has still been reported from different composting studies, indicating the complex nature of this process. The objectives of this study were to: 1) study thermal …

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The Design & Implementation Of An Abstract Semantic Graph For Statement-Level Dynamic Analysis Of C++ Applications, Edward Duffy Dec 2011

The Design & Implementation Of An Abstract Semantic Graph For Statement-Level Dynamic Analysis Of C++ Applications, Edward Duffy

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In this thesis, we describe our system, Hylian, for statement-level analysis,
both static and dynamic, of a C++ application. We begin by extending the
GNU gcc parser to generate parse trees in XML format for each of the
compilation units in a C++ application. We then provide verification that the
generated parse trees are structurally equivalent to the code in the
original C++
application. We use the generated parse trees, together with an augmented
version of the gcc test suite, to recover a grammar for the C++ dialect that
we parse. We use the recovered grammar to generate a schema …

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A Web-Integrated Environment For Component-Based Software Reasoning, Charles Cook Dec 2011

A Web-Integrated Environment For Component-Based Software Reasoning, Charles Cook

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This thesis presents the Web IDE, a web-integrated environment for component-based software reasoning. The Web IDE is specifically tailored to emphasize the relationships among various components in component-based software engineering (CBSE) and to facilitate reasoning. It allows students to use RESOLVE, a component-based, integrated specification and programming language, to build components and systems, providing real-time feedback that can be used to reason about the correctness of their component implementations. Real-time interaction and relationship focused component presentation reinforces CBSE and reasoning principles in a way not possible with traditional programming exercises and file management systems.
The Web IDE has gone through …

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Prevention Of Iron- And Copper-Mediated Oxidative Dna Damage By Neurotransmmitters And Related Compounds: Evidence For Metal Binding As An Antioxidant Mechanism, Carla Garcia Dec 2011

Prevention Of Iron- And Copper-Mediated Oxidative Dna Damage By Neurotransmmitters And Related Compounds: Evidence For Metal Binding As An Antioxidant Mechanism, Carla Garcia

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An array of health concerns have been attributed to oxidative DNA damage from the hydroxyl radical (*OH), and the presence of the most biologically available metals iron and copper perpetuate the production of this radical through the Fenton and Fenton-like reactions, respectively. The concentrations at which flavonol and polyphenol antioxidants prevent 50% of DNA damage (IC50) were measured using gel electrophoresis assays upon Fe(II)/H2O2- and Cu(I)/H2O2-mediated DNA damage (Chapter 2). Results show that catechol- and gallol-containing antioxidants differ greatly in preventing DNA damage by Cu(I)/H2O2, compared to Fe(II)/H2O2, behavior that was explained using electron paramagnetic resonance spectroscopy. Semiquinone and other …

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