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Full-Text Articles in Engineering

Set Up Time Reduction And Quality Improvement On The Shop Floor Using Different Lean And Quality Tools, Seetha Ram Bavuluri May 2012

Set Up Time Reduction And Quality Improvement On The Shop Floor Using Different Lean And Quality Tools, Seetha Ram Bavuluri

All Theses

The purpose of this thesis document is to describe a method developed for reducing setup time in machining processes and simultaneously improve the quality of production after setup. Bosch Rexroth at Fountain Inn is a semi-automated plant and is still in its initial stages of standardizing the setup process. Setup time at different machining centers includes: machining time, inspection time, loading and unloading times and deburring. The focus of the described method is in reducing setup times related to inspection time and loading and unloading times. To achieve success in these problems the following new tools were developed: first piece …


Connected Vehicle Supported Electric Vehicle Charging Operations And Related Infrastructure Issues, Jennifer Johnson May 2012

Connected Vehicle Supported Electric Vehicle Charging Operations And Related Infrastructure Issues, Jennifer Johnson

All Theses

Due to the tremendous political, economic and environmental pressures the transportation sector is facing, the United States finds itself devoting more energy to innovative solutions like electric vehicle (EV) technologies. The first objective of this study was to analyze how utilizing real-time information dissemination transferring capabilities to vehicles, as envisioned in the 'connected vehicle' system, could effectively facilitate the EV charging process at fast-charging stations. By simulating a traffic network of EVs in Matlab, it was found that the total time due to the battery charging process could be optimized for EVs that were able to use connected vehicle communications. …


A System-Generated Password And Mnemonic Approach To Optimize The Security And Usability Of Text-Based Passwords, Sanjaykumar Ranganayakulu May 2012

A System-Generated Password And Mnemonic Approach To Optimize The Security And Usability Of Text-Based Passwords, Sanjaykumar Ranganayakulu

All Theses

In this study a novel password generation policy called the system-generated password and mnemonic was designed and implemented. The intent of this policy was to optimize both the security and usability of text-based passwords. After implementing the policy we evaluated its usability and compared it with three other existing policies: user-generated password, system-generated password and user-generated mnemonic for a system-generated password. In order to have a fair comparison among the policies we maintained a constant level of security of 30±2 entropy as dictated by NIST level 2 standards.
The study involved 64 participants, equally divided into four groups, 16 in …


Network Service Delivery And Throughput Optimization Via Software Defined Networking, Aaron Rosen May 2012

Network Service Delivery And Throughput Optimization Via Software Defined Networking, Aaron Rosen

All Theses

In today's world, transmitting data across large bandwidth-delay product (BDP) networks requires special configuration on end users' machines in order to be done efficiently. This added level of complexity creates extra cost and is usually overlooked by users unknowledgeable to the issues. This is one example problem which can be ameliorated with the emerging software defined networking (SDN) paradigm. In an SDN, packet forwarding is controlled via software controllers. In an OpenFlow SDN, a controller can control the forwarding, rewriting, and dropping of packets based on their header attributes. The ability to handle packets in customizable ways in software has …


Statistical Analysis Of The Stress-Energy Methodology Applied To Cushion Curve Determination, Kendalyn Paulin May 2012

Statistical Analysis Of The Stress-Energy Methodology Applied To Cushion Curve Determination, Kendalyn Paulin

All Theses

The stress-energy method is a proposed enhancement to ASTM D1596 that reduces all drop height, thickness and static load combinations into a single equation that can be used to generate any reasonable cushion curve for a particular material. There remains a question as to how accurate the stress-energy method can predict acceleration values and whether it is statistically comparable to ASTM D1596. There are three phases to this research that attempt to determine the accuracy of the stress-energy method: gathering data using the stress-energy method and analyzing the goodness of fit of the stress-energy equation, predicting a cushion curve and …


Charging Kinetics Of Micropores In Supercapacitors, Daniel Oberklein May 2012

Charging Kinetics Of Micropores In Supercapacitors, Daniel Oberklein

All Theses

The charging kinetics of Electric Double Layer Capacitors (EDLC) were studied using a continuum model based on the Poisson-Nernst-Planck (PNP) Equations, with the additional modeling of the bulk fluid motion in the electrolyte using the Navier-Stokes Equations. The results demonstrate that the addition of bulk flow modeling yields a faster charging rate and higher charging current due to the additional convective component of the current resulting from the bulk fluid motion. A parametric study was conducted to determine the effect of various physical parameters of the EDLC system on the charging kinetics. Decreased fluid viscosity results in a faster charging …


A Person Following Algorithm For Use With A Single Forward Facing Rgb-D Camera On A Mobile Robot, Sean Ficht May 2012

A Person Following Algorithm For Use With A Single Forward Facing Rgb-D Camera On A Mobile Robot, Sean Ficht

All Theses

This thesis examines the problem of person following. A person following algorithm can be separated into two distinct parts: the detection and tracking of a target and the actual following of a target. This thesis focuses mainly on the detection and tracking of a target person. For the purposes of this thesis a simple robot control architecture is used. The robot moves to follow the target in a straight line. No path planning is considered when executing robot movement.
This thesis aims to accomplish three tasks. First, the system should be able to track and follow a target when no …


Effects Of Different Microenvironmental Conditions On The Growth And Differentiation Of Dental Pulp Stem Cells, Matthew Cupelli May 2012

Effects Of Different Microenvironmental Conditions On The Growth And Differentiation Of Dental Pulp Stem Cells, Matthew Cupelli

All Theses

Human teeth are very complex structures that are susceptible to many different pathologies due to poor dental health. Currently, there are many restorative methods to reestablish some of the function that teeth have, but the materials used in these methods all have drawbacks and cannot fully mimic the native teeth. Tissue engineering research groups have begun to explore regenerating bone or dental tissue using mesenchymal stem cells derived from the bone marrow. However, our group focuses on regenerating dental tissues using multipotent stem cells from dental pulp.
Dental pulp stem cells (DPSCs) have shown similarities to bone marrow stem cells …


Development And Calibration Of Central Pressure Filling Rate Models For Hurricane Simulation, Fangqian Liu May 2012

Development And Calibration Of Central Pressure Filling Rate Models For Hurricane Simulation, Fangqian Liu

All Theses

This study presents the development of a new central pressure filling rate model to characterize the rate at which hurricanes or tropical storms decay after landfall. It has been shown that the post landfall decay rate of hurricanes is closely related to the time after landfall, the size of hurricane and proximity of the hurricane eye to the coastline. In addition, it has been observed that the decay rates of hurricanes are geographically dependent. Based on these observations, a set of simple empirical models expressed in
terms of exponential and linear equations are utilized to characterize the decay rate of …


Nanoparticles In Solution-Derived Chalcogenide Glass Films, Spencer Novak May 2012

Nanoparticles In Solution-Derived Chalcogenide Glass Films, Spencer Novak

All Theses

The results in this thesis are from our efforts to modify the optical properties of solution-derived chalcogenide glass films by the incorporation of nanomaterials. First, the composition Ge23Sb7S70 was selected as the appropriate glass matrix for testing because solution-derived films of this composition have been well-studied in our group. Additionally, this composition was found to be less sensitive to certain processing parameters than As2S3, another well-studied, candidate chalcogenide glass composition, making Ge23Sb7S70 more suitable for the addition of nanomaterials. Optimization of film process parameters was performed to obtain high-quality films appropriate for doping with nanomaterials. This consisted of determining the …


Qualified Affordance-Based Design, Jun Hu May 2012

Qualified Affordance-Based Design, Jun Hu

All Theses

Function-based approaches are taught by the engineering design community and implemented in practice. The most significant advantage of these approaches is that they can guide the designers to abstract the essential problems from the design requirements, build the function-based models, and consequently provide the direction of the solution. However, due to the lack of a consistent scientific definition on the meaning of the function, these approaches may be contradictory when representing human-centered aspects, features, and non-physical purposes. To address this issue, design researchers have pursued two general directions: (1) broadening the meaning of function and (2) introducing an alternative scientific …


A Case Study In Challenging And Validating Engineering Requirements With Value-Based Techniques, Seth Crouch May 2012

A Case Study In Challenging And Validating Engineering Requirements With Value-Based Techniques, Seth Crouch

All Theses

Requirements are an essential element to engineering design as they are used to focus idea generation during conceptual design, provide criteria for decision making during concept selection, and verify the chosen concept fulfills product needs. Because they are essential to the entire design process, great emphasis needs to be put on ensuring that they are correct. This research focuses on a value-based methodology useful for challenging and validating established requirements. A case study was conducted using this process on a project involving the design of a vehicle seat. This case study shows that this approach provides more persuasive evidence to …


Remote Detection Of Ephemeral Wetlands In Mid- Atlantic Coastal Plain Ecoregions: Lidar And High-Throughput Computing, Paul Leonard May 2012

Remote Detection Of Ephemeral Wetlands In Mid- Atlantic Coastal Plain Ecoregions: Lidar And High-Throughput Computing, Paul Leonard

All Theses

Ephemeral wetlands are ecologically important freshwater ecosystems that occur frequently throughout the Atlantic coastal plain ecoregions of North America. Despite the growing consensus of their importance and imperilment, these systems historically have not been a national conservation priority. They are often cryptic on the landscape and methods to detect ephemeral wetlands remotely have been ineffective at the landscape scales necessary for conservation planning and resource management. Therefore, this study fills information gaps by employing high-resolution light detection and ranging (LiDAR) data to create local relief models that elucidate small localized changes in concavity. Relief models were then processed with local …


Assessment Of A Safe Driving Program For Novice Drivers And Smart Jersey Barrier Design To Minimize Animal-To-Vehicle Collisions, Lance Clark May 2012

Assessment Of A Safe Driving Program For Novice Drivers And Smart Jersey Barrier Design To Minimize Animal-To-Vehicle Collisions, Lance Clark

All Theses

Each year, the total number of vehicles, motorists, highway infrastructures, and distance traveled by drivers increases on a global basis. This rise in personal and commercial ground vehicle usage brings with it the advantages of the modern age, but it is not without societal cost. Vehicular incidents result in tens of thousands of deaths each year in the United States alone. For this reason, research has been performed to advance driver safety while simultaneously providing wildlife with means to avoid animal-to-vehicle collisions (AVC). In this thesis, two solutions are proposed: a driver education program with classroom experiences, in-vehicle resources, and …


Dynamic Endothelialization Of Aortic Heart Valve Scaffolds, Richard Pascal Jan 2012

Dynamic Endothelialization Of Aortic Heart Valve Scaffolds, Richard Pascal

All Theses

Cardiovascular disease is the number one killer worldwide affecting both the heart and blood vessels. Valvular heart disease can arise from calcification, and structural deterioration resulting in a stenotic or regurgitant valve incapable of proper function. With approximately 275,000 valve replacements performed annually worldwide, the need for replacement heart valves is well established. Currently, treatment of valvular heart disease is limited to two options (mechanical and bioprosthetic). Both replacement valves have their own drawbacks, which have driven research in the bioengineering field to focus on the development of a tissue engineered heart valve (TEHV) capable of growth and self-repair.
A …


A Computational Investigation For Potential Improvements, Angela Grujicic Dec 2011

A Computational Investigation For Potential Improvements, Angela Grujicic

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Mild traumatic brain injury (mTBI), colloquially known as a concussion, is the most common injury in modern wars. This domination of mTBI is hypothesized to be due to a combination of unconventional explosives and better protection and care of the patients, increasing survivability. While the majority of the body is covered in armor, the head is left relatively unprotected. The current Advanced Combat Helmet (ACH) has been designed to protect the warfighter against ballistic impacts and impacts against a hard surface, with little to no regard to blast loading. Polyureas, a class of microsegregated, elastomeric copolymers, has been shown to …


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 …


Evaluation Of Bioaugmentation Strategies To Treat High Concentrations Of Chloroform And Carbon Tetrachloride, Han Wang Dec 2011

Evaluation Of Bioaugmentation Strategies To Treat High Concentrations Of Chloroform And Carbon Tetrachloride, Han Wang

All Theses

Halogenated methanes, including carbon tetrachloride (CT) and chloroform (CF), are significant groundwater contaminants. Options for bioremediation of high concentrations are limited. Previous studies have shown that an enrichment culture (designated DHM-1) that grows on corn syrup has the potential for use in bioaugmentation. DHM-1 cometabolically biotransforms high concentrations of CT and CF to nontoxic end products (mainly CO, CO2, and organic acids) in the presence of vitamin B12 (approximately 3% of chlorinated methanes on a molar basis). Sulfide is also required by this culture to function properly. However, insufficient data are available on its performance under field conditions. Also, it …


Laminar Flame Speed Estimation From Experimental Data Using A Quasi-Dimensional Turbulent Flame Entrainment Combustion Simulation For Spark Ignition Engines, Akash Desai Dec 2011

Laminar Flame Speed Estimation From Experimental Data Using A Quasi-Dimensional Turbulent Flame Entrainment Combustion Simulation For Spark Ignition Engines, Akash Desai

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The goal of this research is to develop a thermodynamic simulation of spark-ignition engine combustion that uses a predictive burn-rate model. Previously done thermodynamic engine simulations in MATLAB are based on a specified burn rate model. Also, the effect of turbulence parameters on the rate of mass burn up is not considered. A predictive burn rate model is necessary to study the effect of different fuels on spark ignition engine combustion. The effect of laminar flame speed and turbulent intensity on combustion is difficult to assess experimental due to the difficulty in the measurement of these two variables. Thus, the …


Product And Process Based Assembly Time Estimation In Engineering Design, Michael Miller Dec 2011

Product And Process Based Assembly Time Estimation In Engineering Design, Michael Miller

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This thesis presents the research and development of two assembly time estimation techniques for the automotive industry. Both of these techniques are capable of being implemented early in the product life-cycle of a vehicle and require information available in this phase. Currently, assembly time estimation is performed after production has begun and is a tedious manual process requiring hours of motion-time method studies for each assembly activity. The techniques proposed in this thesis can both be performed prior to the start of production and are capable of being performed automatically after the initial mapping.
The first assembly time estimation technique …


Development And Application Of A Three-Dimensional Probabilistic Wind-Borne Debris Trajectory Model, James Grayson Dec 2011

Development And Application Of A Three-Dimensional Probabilistic Wind-Borne Debris Trajectory Model, James Grayson

All Theses

This research presents a probabilistic debris trajectory model adapted from current 6-degree-of-freedom (6-DoF) deterministic models, in which the aleatoric (inherent) uncertainty is explicitly considered in the proposed probabilistic model. While the inherent randomness in the debris flight trajectory is irreducible due to the wind turbulence, variation in wind direction, gustiness of the wind event and so forth, the proposed probabilistic model seeks to address these uncertainties through Monte Carlo simulations with the appropriate statistical distributions applied to the governing equations of motion of the debris. Verification of the probabilistic debris trajectory model is performed through an analytical and visual comparison …


Empirical Study: Failure Of Glass-To-Metal Seals During Shock Loading, William Horton Dec 2011

Empirical Study: Failure Of Glass-To-Metal Seals During Shock Loading, William Horton

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The goal of this thesis was to determine the empirical failure mechanisms and sequence of cartridge actuated devices (CADs) experiencing failure of the glass-to-metal (G/M) seal. Impact loading was conducted with a drop weight machine at room temperature and 300¡F, and then empirically analyzed with high speed video. Resulting peak overload force, shear stress, and impulse were all calculated. The room temperature samples were found to absorb twice the impulse upon failure as the elevated temperature G/M seals. Closed-form and three-dimensional finite element analysis was used to determine the stress state and deformation upon loading. Furthermore, high speed data was …


The Integration Of Building Information Modeling (Bim) Into Civil Engineering Curricula, Jason Cooksey Dec 2011

The Integration Of Building Information Modeling (Bim) Into Civil Engineering Curricula, Jason Cooksey

All Theses

Building Information Modeling (BIM) is an emerging technology used in the Architecture/Engineering/Construction (AEC) industry. The proliferation of BIM usage across the industry has been swift and prolific. Academia has lagged behind the adoption rate of the industry by not producing enough students with BIM exposure. Thus, the question is whether civil engineering curricula should provide an understanding of BIM technology to students entering the design and construction profession. The immediate objective of this research is to determine if it is important to provide exposure of BIM to undergraduate or graduate students in the civil engineering curricula and if so to …


Determining Transverse Design Forces For A Next-D Bridge Using 3d Finite Element Modeling, Robert Funcik Dec 2011

Determining Transverse Design Forces For A Next-D Bridge Using 3d Finite Element Modeling, Robert Funcik

All Theses

This thesis looks into the use of 3D Finite Element Modeling to determine the transverse design forces for short-span bridges built using the Northeast Extreme Tee with integral deck (NEXT-D) beam. Models were built using either solid elements or shell elements to represent the bridge deck, and the results were compared. The stiffness of the shear keys were taken into account during the modeling process. Results were compared to the AASHTO strip width method for design bridge decks, and the results showed that the strip width method would not be adequate for the design of NEXT-D bridges, so specific live …


Modeling Impacts Of Foothills Parkway Construction On Stream Water Quality Using Real-Time Remote Monitoring, Clark Chewning Dec 2011

Modeling Impacts Of Foothills Parkway Construction On Stream Water Quality Using Real-Time Remote Monitoring, Clark Chewning

All Theses

ABSTRACT
The need to monitor surface water quality has been increasingly recognized in recent years in environmental and natural resource management. The advent of real-time remote monitoring technologies has accelerated and enhanced this process. Field observations of water quality data are able to be conducted and analyzed in ways that were previously unavailable.
The objectives of this research were to deploy and test a real-time remote monitoring system for three small watersheds (Hembree, Dunn, and Rudd Hollows) in the Great Smoky Mountains. The watersheds ranged in size from 12 to 19 ha. Real-time remote monitoring stations were established in three …


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 …


Role Of Surface Coatings In Lithium-Ion Batteries, Archana Kayyar Dec 2011

Role Of Surface Coatings In Lithium-Ion Batteries, Archana Kayyar

All Theses

Rechargeable batteries that can charge and discharge at high rates have applications in hybrid and plug-in hybrid vehicles and they provide energy storages for wind energy. Various methods like reducing particle size, aliovalent doping and carbon coating have been researched in order to attain higher charge and discharge rates in rechargeable Li-ion batteries. In this work, the electrode materials were coated with amorphous films in an attempt to improve the rate capability of the batteries.
A study by Kang and Ceder suggested that a Li4P2O7-like 'fast-ion conducting surface phase' could form on the surface …


A Methodology For Estimating And Comparing The Lifecycles Of High-Build And Conventional Waterborne Pavement Markings On Primary And Secondary Roads In South Carolina, Joseph Robertson Dec 2011

A Methodology For Estimating And Comparing The Lifecycles Of High-Build And Conventional Waterborne Pavement Markings On Primary And Secondary Roads In South Carolina, Joseph Robertson

All Theses

Highway pavement markings constitute a vital component of roadway transportation systems and provide crucial visual cues for the basic driver task of following the road. In 2008, the South Carolina Department of Transportation (SCDOT) initiated a multi-year study to evaluate pavement markings on non-interstate primary and secondary roads in South Carolina. This thesis discusses development of a methodology for estimating and comparing the lifecycles of high-build and conventional waterborne pavement markings based on retroreflectivity levels. The methodology was developed using nearly 3 years of field data from 66 sites throughout South Carolina. This thesis provides an overview of data collection …


Fault-Tree Model For Bridge Collapse Risk Analysis, Caitlyn Davis-Mcdaniel Dec 2011

Fault-Tree Model For Bridge Collapse Risk Analysis, Caitlyn Davis-Mcdaniel

All Theses

Bridges are vital components of the United States surface transportation infrastructure and, moreover, support the growth of our nation's economy. However, over the past few decades the design capacity and service condition of many bridges in the U.S. has been challenged. Numerous incidents of bridge collapse call for an urgent need to develop a systematic method of assessing the failure risks and identifying the initiating events that can lead to a bridge collapse. This thesis presents a process of bridge failure risk analysis through fault-tree modeling and identification of specific countermeasures, to minimize failure risk, related to structural health monitoring …


The Development Of A Far Red To Near Infrared Fluorescent Probe For Use In Optical Imaging, Margaret Fiedler Dec 2011

The Development Of A Far Red To Near Infrared Fluorescent Probe For Use In Optical Imaging, Margaret Fiedler

All Theses

New techniques for biological optical imaging are of great interest for the detection and visualization of processes and disease in both clinical and research areas. One major advancement has been the use of far red and near infrared (NIR) light, as it has the ability to penetrate tissues deeper than other parts of the spectrum which are readily scatter and absorbed by the surroundings. In order to improve the signal to noise ratio and resolution of optical images, contrast agents are used. Fluorescent markers can be modified to attach to specific molecular targets, creating small molecular probes. These targets can …