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Full-Text Articles in Engineering

In Vitro Analysis Of Auto-Loom Woven Test Patches For Hernia Repair, Bryant Mersereau Aug 2010

In Vitro Analysis Of Auto-Loom Woven Test Patches For Hernia Repair, Bryant Mersereau

All Theses

Hernias are defects in the layers of the abdominal wall that can cause discomfort or pain and lead to serious health problems if left untreated. A significant portion of the world's population is afflicted by hernia formation, and the cost of treating those affected is in the billions of dollars in the US alone. The current best practices for repairing hernias involve the surgical implantation of polymeric meshes over and around the defect site. The mesh, acting as a synthetic replacement for the damaged abdominal wall layers, provides a barrier to further visceral protrusions through the defect, a support framework …


Timing Side-Channel Attacks On Ssh, Harikrishnan Bhanu May 2010

Timing Side-Channel Attacks On Ssh, Harikrishnan Bhanu

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In most secure communication standards today, additional latency is kept to a minimum to preserve the Quality-of-Service. As a result, it is possible to mount side-channel attacks using timing analysis. In this thesis we discuss the viability of these attacks, and demonstrate them by inferring Hidden Markov Models of protocols. These Hidden Markov Models can be used to both detect protocol use and infer information about protocol state. We create experiments that use Markov models to generate traffic and show that we can accurately reconstruct models under many circumstances. We analyze what occurs when timing delays have enough jitter that …


Acceleration Of Spiking Neural Networks On Single-Gpu And Multi-Gpu Systems, Venkittaraman Vivek Pallipuram Krishnamani May 2010

Acceleration Of Spiking Neural Networks On Single-Gpu And Multi-Gpu Systems, Venkittaraman Vivek Pallipuram Krishnamani

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There has been a strong interest in modeling a mammalian brain in order to study the architectural and functional principles of the brain and offer tools to neuroscientists and medical researchers for related studies. Artificial Neural Networks (ANNs) are compute models that try to simulate the structure and/or the functional behavior of neurons and process information using the connectionist approach to computation. Hence, the ANNs are the viable options for such studies.
Of many classes of ANNs, Spiking Neuron Network models (SNNs) have been employed to simulate mammalian brain, capturing its functionality and inference capabilities. In this class of neuron …


The Effects Of Temperature And Humidity On Cushioning Properties Of Expanded Polylactic Acid Foam, Jason Szymanski May 2010

The Effects Of Temperature And Humidity On Cushioning Properties Of Expanded Polylactic Acid Foam, Jason Szymanski

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This research studied expanded polylactic acid cushioning foam and the effect the conditioning environment had on its shock absorbing properties. Polylactic acid, as a polymer, has been available since the 1960s. Only recently has the polymer been adapted to allow expanded foaming. This material's significance to industry lies in its sustainability. With global awareness at all-time highs, the push for sustainable materials is rising. The adaptation of PLA to EPLA is a result of that push. This research represents the first of its kind, by characterizing EPLA for cushioning and also to study the effects temperature and humidity on the …


Liquid-Liquid Equilibrium For Iodine-Hydroiodic Acid-Water Mixtures At Elevated Temperatures And Pressures For The Sulfur-Iodine Cycle, Sarah Mena May 2010

Liquid-Liquid Equilibrium For Iodine-Hydroiodic Acid-Water Mixtures At Elevated Temperatures And Pressures For The Sulfur-Iodine Cycle, Sarah Mena

All Theses

An alternative scenario to the overdependence on fossil fuels is the use of thermochemical cycles to split water into hydrogen and oxygen. The Sulfur-Iodine (SI) cycle, developed at General Atomics in the mid 1970s, is a leading candidate of international interest for the centralized production of hydrogen from nuclear and/or solar power. For a comprehensive assessment of the SI cycle, thermodynamic data for I2-HI-H2O mixtures at elevated temperatures and pressures have been identified as a basic research need.

The focus of this study was liquid-liquid equilibrium (LLE) measurements for the above system. To carry out the measurements, a continuous-flow apparatus …


Sensitivity Constrained Pmu Placement Utilizing Multiple Methods, Zheng Zhao May 2010

Sensitivity Constrained Pmu Placement Utilizing Multiple Methods, Zheng Zhao

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Phasor Measurement Unit (PMU), which is based on the GPS technique, is able to provide power engineers with immediate and precise measurements. By utilizing PMUs, the reliability and stability in power system are expected to be improved. Conventionally, an optimal PMU placement is considered to use the least number of units to make the entire system completely observable. In this thesis, it is recommended to not only optimize the number of PMUs but also install the majority of PMUs on the most sensitive buses in a power system. Thus a bus sensitivity analysis based on Decoupled Power Flow method is …


Ie Tools In Construction - Small Tools Spreadsheet, Ronald Goodson May 2010

Ie Tools In Construction - Small Tools Spreadsheet, Ronald Goodson

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This document will explore the development and implementation of a spreadsheet tool that will provide for effective planning, procurement, and management of 'small tools' on a construction site - small tools are relatively inexpensive items that are usually handheld. The following five chapters cover the development of the spreadsheet. Both methodology and the calculation process are explored in detail and all facets of the spreadsheet are explained. A key component of the development process is that end users were involved in the entire development process to ensure the spreadsheet met their needs. In general, users input several criteria regarding work …


Analytical Seismic Fragility Curves For Skewed Multi-Span Steel Girder Bridges, Ian Sullivan May 2010

Analytical Seismic Fragility Curves For Skewed Multi-Span Steel Girder Bridges, Ian Sullivan

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Most of the past seismic fragility studies on typical highway bridges in the Central and Southeastern United States (CSUS) have focused on regular multi-span bridges with little to no skew. However, past earthquakes and studies have shown that skewed multi-span simply supported bridges may also be susceptible to earthquake damage, specifically causing coupled responses (longitudinal and transverse) that place more demand on individual components. With over 27 percent of simply supported steel girder highway bridges in the CSUS having a skew angle over 15 degrees, there is a specific need to further quantify the vulnerability of such bridges exposed to …


Plutonium - Humic Acid Stability Constant Determination And Subsequent Studies Examining Sorption In The Ternary Pu(Iv) - Humic Acid - Gibbsite System, Trevor Zimmerman May 2010

Plutonium - Humic Acid Stability Constant Determination And Subsequent Studies Examining Sorption In The Ternary Pu(Iv) - Humic Acid - Gibbsite System, Trevor Zimmerman

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Plutonium has been released to the environment through a variety of intentional and unintentional mechanisms, including atmospheric testing, disposition from weapons manufacturing processes, and subsurface disposal. Therefore, a thorough understanding of the chemical, physical, and biological processes affecting plutonium transport is imperative. It has been shown that humic acid (HA) (a refractory component of natural organic matter (NOM)) can effectively solubilize plutonium (Santschi et al., 2002). Increased solubility may result in enhanced subsurface transport, due to the higher concentration of Pu in the aqueous phase. In contrast, the formation of ternary surface complexes may hinder actinide transport. Solution pH is …


Responses Of Problematic Algae To Algaecide Exposures, West Bishop May 2010

Responses Of Problematic Algae To Algaecide Exposures, West Bishop

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Excessive growths of algae can cause significant disruption of critical water resource usages including: drinking, irrigation, recreation as well as be aesthetically displeasing. Water resource managers are often compelled to take action to mitigate these nuisance algal infestations. Algaecides can be efficient and effective management options to rapidly suppress algal blooms and restore water usages. However, laboratory and field data are required to accurately predict responses to an application as well as potential risks to non-target organisms. Laboratory experiments were used to measure the responses of problematic algae to algaecide exposures and evaluate the margin of safety to sensitive, non-target …


Biodegradable Polymer Blends And Composites From Proteins Produced By Animal Co-Product Industry, Bernice Nzioki May 2010

Biodegradable Polymer Blends And Composites From Proteins Produced By Animal Co-Product Industry, Bernice Nzioki

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ABSTRACT
Development of new green materials from by-products of animal rendering industries would provide a substantial economic return to animal rendering processors. Meat and bone meal (MBM), one of the products of the rendering industry, has potential for numerous bio-based applications. This research focuses on fabrication of plastics blends made of MBM (Meat and bone meal) and UHMWPE (ultra high molecular weight polyethylene). We investigated thermal, morphological, water absorption and mechanical properties of the plastics. The plastics were compression molded and their properties were examined.
DSC thermographs of the blends indicated that the thermal properties of UHMWPE did not change …


Electrokinetic Manipulation Of Particles And Cells In Microfluidic Devices, Christopher Church May 2010

Electrokinetic Manipulation Of Particles And Cells In Microfluidic Devices, Christopher Church

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With the recent advancement in micro-fabrication technology, lab-on-a-chip devices have been developed in order to perform biological analysis through cell manipulation. Microchannels used in these lab-on-a-chip devices have been demonstrated to accurately perform many different cell manipulation techniques such as focusing, separation, trapping, and lysis. Although there are many methods available for these techniques, electrokinetics has been rapidly gaining popularity due to the simplicity of application and removal of the need for in channel micro-structures. This thesis studies the use of electrokinetic flow and accompanying phenomena in various structured microchannels to perform focusing, separation, trapping, and lysis of cells. Three …


Modeling Of A Porous Metal Foam Cryogenic Counter Flow Heat Exchanger, Craig Fortier May 2010

Modeling Of A Porous Metal Foam Cryogenic Counter Flow Heat Exchanger, Craig Fortier

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This thesis involves the modeling of cryogenic fluids through a porous metal foam counter flow heat exchanger. Although much research has been completed involving light weight high porosity metal foams in recent years, research performed on the subject of mid range porosities in metal foams and their use in heat exchangers has been relatively untouched. Even less literature is available pertaining to the effects of cryogenic fluids in porous metal foams.
Much about heat exchanger performance and pressure drop depends on the structure and relative density of the metal foams. This has been elaborated in several sources, but only for …


'Transfer Effect Study Of A Virtual Borescope In Training Aircraft Maintenance Technicians', Melissa Dorlette Paul May 2010

'Transfer Effect Study Of A Virtual Borescope In Training Aircraft Maintenance Technicians', Melissa Dorlette Paul

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The Federal Aviation Administration (FAA) has acknowledged training as an important tactic to improve the trustworthiness of inspection. This study was conducted to test the transfer of the skills learned with a simulator into the real world. For this purpose, data from seventeen students in the AMT program of Greenville Technical College was analyzed. Objective data was taken to assess the group's performance on the simulator after each session of training. The comparison between two groups was made using objective data, collected while the subjects went through a test on a real engine and using the real borescope, and subjective …


Women As Sustainability Leaders In Engineering: Evidence From Industry And Academia, Jennilee Harrison May 2010

Women As Sustainability Leaders In Engineering: Evidence From Industry And Academia, Jennilee Harrison

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Women are underrepresented in engineering education and practice, which limits the quality of the engineering workforce. One way to increase the participation of women in engineering is to emphasize subjects that appeal to them and emphasize skills at which they are especially adept. A subject that may fit this description is sustainability. The purpose of this research is to compare the percentage of women in selected sustainable engineering leadership positions to the percentage of women in general engineering leadership positions, to examine whether the subject of sustainability may help increase participation of women in engineering. Gender data was collected for …


Re-Engineering A Trash/Recycling Collection Vehicle Based On Challenging Customer Requirements, Edward Smith May 2010

Re-Engineering A Trash/Recycling Collection Vehicle Based On Challenging Customer Requirements, Edward Smith

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Engineering design starts with the definition of design requirements. These requirements define the design problem and must be satisfied for a solution to be acceptable. While many design methodologies exist for defining design requirements, none presently provides a systematic approach for designers to challenge requirements. Yet, Pahl and Beitz, Hazelrigg, and Suh all argue that a designer should continually question the need for each requirement and refine them as the product evolves. Thus, there exists a need to develop a comprehensive method that enables a designer to verify, review/question, and revise requirements throughout the design process. This research uses the …


System Modeling And Power Management Strategy For A Series Hydraulic Hybrid Vehicle, Sisay Molla May 2010

System Modeling And Power Management Strategy For A Series Hydraulic Hybrid Vehicle, Sisay Molla

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A hydraulic hybrid vehicle draws propulsion power from an internal combustion engine as its prime mover and a gas-charged hydro-pneumatic accumulator as its energy buffer. The accumulator serves the purposes of storing regenerated braking energy and supplementing engine power as determined by an on-board power management strategy. In the configuration known as a series hydraulic hybrid powertrain, the engine is mechanically decoupled from the vehicle's wheels thereby offering excellent opportunities for maximizing energy efficiency and reducing pollutant emissions.
This thesis dealt with the development of a causally interconnected, non-linear, dynamic model of a series hydraulic hybrid powertrain featuring independently controllable …


Fpga Based Timing Module And Optical Communication Card Design For Spallation Neutron Source, Biswa Singh May 2010

Fpga Based Timing Module And Optical Communication Card Design For Spallation Neutron Source, Biswa Singh

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The Timing Module and Optical Communication Card (OCC) are used for acquisition of neutron event data by the instrument systems at the Spallation Neutron Source (SNS) neutron scattering facility. The instrument systems produce a very large flux of neutrons of varying energies over a short time period through the spallation process. The Timing Module and OCC require high-bandwidth communication to ensure high-speed data movement to the memory in the data collection system without loss of neutron data. The existing implementations use a standard PCI-X bus interface to transfer the data between the cards and the host computer. The data processing …


An Integral Equation Analysis Of A Two-Aperture Coaxial Waveguide, John Luke May 2010

An Integral Equation Analysis Of A Two-Aperture Coaxial Waveguide, John Luke

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Two different, two-aperture coaxial waveguide configurations are modeled. Integral equations are formulated and then solved by means of the Method of Moments. The results of the analyses are used to formulate a microwave network representation for each structure. Commercial electromagnetic modeling software, along with data acquired through the building and testing of one of the structures, is used to prove the validity of the solution technique developed within the text.


Kinetic And Finite Element Modeling For Firing Brick, Daniel Mckinney May 2010

Kinetic And Finite Element Modeling For Firing Brick, Daniel Mckinney

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Kinetic modeling and simulation were used to optimize the firing cycle for brick. This was done to develop a tool for the brick industry to reduce fuel consumption and emissions during firing. A kinetic model was built using shrinkage data from dilatometer measurements and mass loss data from thermogravimetry measurements in order to predict the density as a function of temperature and time. The density of brick was related to the absorption coefficient (C/B), an ASTM standard which is related to the durability of the brick. The kinetic model was used to optimize the firing curve using a rate controlled …


Comprehensive Analysis Of A Student-Centered Active-Learning Integrated Statics And Dynamics Course For Mechanical Engineers, Marisa Orr May 2010

Comprehensive Analysis Of A Student-Centered Active-Learning Integrated Statics And Dynamics Course For Mechanical Engineers, Marisa Orr

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The Student-Centered Active Learning in Undergraduate Programs (SCALE-UP) approach to instructional design was adapted with the goal of delivering more effective statics, dynamics and multivariate calculus instruction and integrated course curricula. Inquiry-based learning exercises were designed, incorporating material from statics and dynamics into multivariable calculus, and vice-versa, as well as integrating statics and dynamics into one course. Analysis included an exploration of student study habits, multiple measures of course effectiveness, and an examination of curricular effects. Challenges of implementation are also discussed.
Study habits of students in an integrated Statics and Dynamics course were assessed through a voluntary survey in …


A Proposed Method To Identify Requirements Significant To Mass Reduction, James Mclellan May 2010

A Proposed Method To Identify Requirements Significant To Mass Reduction, James Mclellan

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Reducing the mass of engineering products holds the potential for significant benefits by reducing material costs, environmental impact, transportation costs, and in the case of vehicles, reducing fuel consumption. While there are many approaches for reducing mass, analyzing requirements has the greatest potential since requirements definition is the earliest phase of product development, where the most design freedom exists. This thesis proposes a requirement analysis method that identifies requirements that impact significant amounts of mass. The research hypothesis is: Engineering requirements can be represented and processed in a systematic manner and linked to physical components and systems, thus enabling mass …


Maximizing Throughput Using Dynamic Resource Allocation And Discrete Event Simulation, Gregory Gunn May 2010

Maximizing Throughput Using Dynamic Resource Allocation And Discrete Event Simulation, Gregory Gunn

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This research studies a serial two stage production system with two flexible servers which can be dynamically assigned to either station. This is modeled using discrete event simulation and more specifically the Arena software package by Rockwell. The goal is to determine dynamic allocation policies based upon the inventory level at each station to maximize the throughput of finished goods out of the system. This model adds to previous work by including actual switching time. The effect of the pre-emptive resume assumption is gauged, and the effectiveness of the OptQuest optimization package is also tested. Studies are conducted to determine …


A Comparison Of Small Scale Laboratory Experiments With The Environmetnal Protection Agency Reccomended Dense Gas Dispersion Models: An Assessment Of The Validity Of Salt Bath Modeling Of Atmospheric Flows, Katie Betz May 2010

A Comparison Of Small Scale Laboratory Experiments With The Environmetnal Protection Agency Reccomended Dense Gas Dispersion Models: An Assessment Of The Validity Of Salt Bath Modeling Of Atmospheric Flows, Katie Betz

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Accurate dense gas dispersion modeling is important in a number of fields from modeling smoke movement in a room to the spreading of dense toxic gas releases such as resulted from the Chlorine spill in Graniteville, SC in 2005. To this end, a series of small scale laboratory experiments using instantaneous releases of a cylindrical, finite volume of dense salt water were performed. In the experiments, the horizontal spread of the dense liquid over a flat surface(i.e. gravity current front position over time) was measured.
The results of these small scale experiments were compared to two dense gas dispersion models …


Detecting And Tracking Tractor-Trailers Using View-Based Templates, Vinay Gidla May 2010

Detecting And Tracking Tractor-Trailers Using View-Based Templates, Vinay Gidla

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Vehicle tracking and classification is an important application of computer vision. There exist mainly two types of tracking techniques: Appearance-based tracking and Feature-based tracking.
Appearance-based techniques generally require a model or template of the target to be tracked. However the model needs to be robust to the multitude of deformations possible in the course of the target's movement. This research explores the use of a collection of view based templates, instead of a single template, to accurately trace the contours of the tractor-trailers in moving traffic.

The tracking begins with creation of a template sequence by manually processing a segment …


Long-Term Performance Of Pavement Markings On Primary And Secondary Roads, Joshua Johnson May 2010

Long-Term Performance Of Pavement Markings On Primary And Secondary Roads, Joshua Johnson

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This research analyzes waterbased and thermoplastic pavement markings on primary and secondary roads in South Carolina. The primary objective of this research was to develop retroreflectivity degradation models for these two pavement marking materials, as well as determine the expected useful life of the markings. Predicting retroreflectivity and marking life is important so that state DOTs may efficiently replace markings in order to reduce safety hazards as well as maintenance costs.
Data collection for this research lasted 21 months, where retroreflectivity of pavement markings was measured on over 100 primary and secondary roads in South Carolina. Variables such as marking …


Liquefaction Analysis Of Three Pleistocene Sand Deposits That Did Not Liquefy During The 1886 Charleston, South Carolina Earthquake Based On Shear Wave Velocity And Penetration Resistance, Aaron Geiger May 2010

Liquefaction Analysis Of Three Pleistocene Sand Deposits That Did Not Liquefy During The 1886 Charleston, South Carolina Earthquake Based On Shear Wave Velocity And Penetration Resistance, Aaron Geiger

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The results of geotechnical investigations at three sites located in the South Carolina Coastal Plain are presented in this thesis. The three sites are called the Hobcaw Barony Borrow Pit site located near Georgetown, SC; the Rest Area Ponds site near Walterboro, SC; and the Lowcountry Sand & Gravel site, also near Walterboro. Near-surface sand deposits at these sites ranged in geologic age from 200,000 to greater than 1,000,000 years. These three sites lie well outside the region of most liquefaction effects observed following the 1886 Charleston earthquake. Investigations conducted at the sites include seismic cone penetration tests with pore …


Modeling Phosphate Adsorption For South Carolina Soils, Jesse Cannon May 2010

Modeling Phosphate Adsorption For South Carolina Soils, Jesse Cannon

All Theses

Eroded sediment and the pollutants it transports are problems in water bodies in South Carolina (SC) and the United States as a whole. Current regulations and engineering practice attempt to remedy this problem by trapping sediment according to settling velocity, and thus, particle size. However, relatively little is known about most eroded soils. In most cases, little experimental data are available to describe a soil's ability to adsorb a pollutant of interest. More-effective design tools are necessary if design engineers and regulators are to be successful in reducing the amount of sediment and sediment-bound pollutants in water bodies. This study …


Traffic Analysis Of Anonymity Systems, Ryan Craven May 2010

Traffic Analysis Of Anonymity Systems, Ryan Craven

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This research applies statistical methods in pattern recognition to test the privacy capabilities of a very popular anonymity tool used on the Internet known as Tor.
Using a recently developed algorithm known as Causal State Splitting and Reconstruction (CSSR), we can create hidden Markov models of network processes proxied through Tor. In contrast to other techniques, our CSSR extensions create a minimum entropy model without any prior knowledge of the underlying state structure. The inter-packet time delays of the network process, preserved by Tor, can be symbolized into ranges and used to construct the models.
After the construction of training …


Performance Of Expanded Polymer Cushion Materials At Less Than One Inch In Thickness, Glen Potter May 2010

Performance Of Expanded Polymer Cushion Materials At Less Than One Inch In Thickness, Glen Potter

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The purpose of this work is to determine whether peak acceleration values can be predicted from existing cushion curves for polymeric materials with thicknesses less than one inch. The secondary purpose is to determine whether the stress energy method of cushion testing can be applied to polymeric foams with thicknesses less than one inch. Cushion curves were created from materials greater than one inch in thickness and from materials less than one inch in thickness. The curves were compared using three methods; linear regression, comparison of cushion curves by ASTM allowable difference between curves and comparison of predicted acceleration values …