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Full-Text Articles in Engineering

Microstructure Modification Of Cu0.2ag2.8sbsete2 Through, Sloan Lindsey Aug 2010

Microstructure Modification Of Cu0.2ag2.8sbsete2 Through, Sloan Lindsey

All Theses

Cu0.2Ag2.8SbSeTe2 is new potential thermoelectric compound that exhibits very low thermal conductivity and a region of glass-like thermal conductivity. The compound phase segregates into AgSbTe2 and Ag2Te phases with Se and Cu acting as isoelectronic dopants. Backscatter SEM imaging is used to study the resulting microstructure. Normally cast samples exhibit cracks forming near the interfaces of the two phases. In this work we show that the cracks are caused by a low temperature monoclinic to cubic phase transition that occurs in the Ag2Te phase. We demonstrate that through rapid quenching we can control the size and shape of the phase …


Structural Bioinformatics Based Method For Predicting The Initial Adsorbed Protein Orientation On A Surface, Aby Thyparambil Aug 2010

Structural Bioinformatics Based Method For Predicting The Initial Adsorbed Protein Orientation On A Surface, Aby Thyparambil

All Theses

In any molecular simulation of protein-surface interaction, the selection of the initial orientation with which the protein would interact with the surface must be first made and is found to be critical in the determination of the bioactive state of the adsorbed protein. While various molecular simulation methods have been developed to identify the preferred orientation, these methods are generally computationally expensive and time consuming, especially for large molecules thereby motivating the current study.
The computational implementation for identifying a preferred orientation was done in MATLAB¨ and directly addresses the current research problem by assuming the protein to be rigid …


The Use Of A-Flute, B-Flute, Ac-Flute, And Bc-Flute Corrugated Paperboard As A Cushioning Material, Alicia Campbell Aug 2010

The Use Of A-Flute, B-Flute, Ac-Flute, And Bc-Flute Corrugated Paperboard As A Cushioning Material, Alicia Campbell

All Theses

Corrugated paperboard, often referred to as cardboard by those outside the
industry, is most often associated with the typical shipping box. Research has proven that cushioning is another possible packaging application for corrugated paperboard.
Corrugate is easily accessed, obtained from a renewable resource, and easily recycled all of which appeal to the increased interest in the use of sustainable materials. Most research related to corrugate as a cushioning material has been performed using
single-wall, C-flute corrugated paperboard.
The purpose of this research was to create cushion curves for A-flute, B-flute,
AC-flute, and BC-flute corrugated paperboard using the stress energy method. …


Determination Of Higher Order Coefficients For A Crack Parallel To An Interface, Venkata Lakshman Kolluru Aug 2010

Determination Of Higher Order Coefficients For A Crack Parallel To An Interface, Venkata Lakshman Kolluru

All Theses

A general method based on the singular integral equations is developed to
computationally determine the higher order coefficients in mixed mode fracture
mechanics. These 'k' and 'T' coefficients are defined with respect to a polar coordinate
system centered at a crack tip, and give asymptotic expressions for stresses and
displacements according to the William's eigenfunction expansions,
(r, ) (2r) k f (n, ) k f (n, ) IIk
ij
II
n
Ik
ij
I
n
n 0
2
1
n
ij      



1
(0, ) (2 ) ( , ) ( , …


An Investigation Of The Response Of Incandescent Lamps And Compact Fluorescent Lamps To Voltage Fluctuation, Christopher May Aug 2010

An Investigation Of The Response Of Incandescent Lamps And Compact Fluorescent Lamps To Voltage Fluctuation, Christopher May

All Theses

This thesis presents the results of tests that were performed on incandescent lamps and compact fluorescents lamps (CFLs) in order to observe their sensitivity to voltage fluctuations that can occur on a power system. The lamps tested were designed for use in a 120V, 60Hz system. They are models that are commonly available in the United States.
In this research, the lamps in question were exposed to four separate tests. The first set of tests analyzed the response of each lamp to a series of long voltage fluctuations that were applied long enough to allow the light output from the …


The Feasibility Of Using An Instrumented Vehicle Equipped With Inertial Navigation Guidence System To Collect Roadway Grade And Cross-Slope Data For Safety Analysis, Cyle Rhoades Aug 2010

The Feasibility Of Using An Instrumented Vehicle Equipped With Inertial Navigation Guidence System To Collect Roadway Grade And Cross-Slope Data For Safety Analysis, Cyle Rhoades

All Theses

In 2005, the Federal Highway Administration (FHWA) requested the development for the initial version of the Model Minimum Inventory of Roadway Elements (MIRE). MIRE is a roadway inventory and traffic data collection data program that has a strong focus on improving the decision process in safety programs. MIRE is not a mandatory state program, but is strongly recommended based on its potential advantages. Some of the data required for MIRE was previously collected as a result of the requirements set from the Highway Performance Monitoring System (HPMS).
This thesis concentrates on the feasibility of determining as-built grade and cross-slope data …


Process Development For The Fractionation And Isolation Of Corn Fiber Hemicellulose, Justin Montanti Aug 2010

Process Development For The Fractionation And Isolation Of Corn Fiber Hemicellulose, Justin Montanti

All Theses

Corn fiber is a co-product of the corn wet-milling process that holds potential to become a value-added product. A process was developed to fractionate and isolate the hemicellulose B component of corn fiber generated by corn wet milling. The process consisted of pretreatment by soaking in aqueous ammonia (SAA) of starch-free corn fiber followed by enzymatic cellulose hydrolysis, during which the hemicellulose B was solubilized by cleavage into xylo-oligosaccharides. The hemicellulose A and B fractions were separated by adjustment of pH, and the hemicellulose B recovered by precipitation with ethanol.
The pretreatment step resulted in a high retention of major …


Characterization Of Compression Molded Sodium Caseinate-Based Films, Kathryn Hartwig Aug 2010

Characterization Of Compression Molded Sodium Caseinate-Based Films, Kathryn Hartwig

All Theses

The objective of this research was to characterize compression molded sodium caseinate based films and investigate the effect of water and glycerol ratios on thermal transition and heal sealing properties. Studies were conducted on films from three variations of film-forming mixtures or 'resins', derived from US patent 4,076,846 containing sodium caseinate (NaCas), methylcellulose (MC), calcium chloride (CaCl2), glycerol (Gly), and distilled water. Moisture sorption isotherms were used to evaluate the water-protein and water-glycerol interactions in the resins. Sorption isotherms were characteristic of most biopolymer material and showed increasing moisture sorption with increasing amounts of glycerol. In compression molded films containing …


Anaerobic Bio-Oxidation Of Vinyl Chloride And Ethene, Anthony Reid Aug 2010

Anaerobic Bio-Oxidation Of Vinyl Chloride And Ethene, Anthony Reid

All Theses

Tetrachloroethene and trichloroethene are among the most prevalent groundwater contaminants found at hazardous waste sites throughout the United States. Since implementing some of the common treatment methods to remediate these hazardous waste sites would exceed hundreds of billions of dollars, there is considerable interest in reducing costs while achieving remediation regulations. Under anaerobic conditions, these compounds can undergo reduction reactions known as reductive dechlorination. This occurs when an electron donor provides the reducing equivalents needed to replace the chlorine atoms with hydrogen atoms. The daughter products from higher chlorinated ethenes are ethene and ethane which can be used to document …


Fabrication Of Fluorescent Nanoparticle-Polymer Composites For Photoactive-Based Materials, Brett Ellerbrock Aug 2010

Fabrication Of Fluorescent Nanoparticle-Polymer Composites For Photoactive-Based Materials, Brett Ellerbrock

All Theses

Nanocomposites of nanoparticles dispersed throughout a polymer matrix have been studied to great length to improve the overall polymer properties. These enhancements are observed in the thermal, physical, and/or optical characteristics. Being able to harness nanoparticles in such a way may help improve fiber technology into the 21st century.
This work was geared toward synthesizing rare earth doped lanthanum fluoride (LaF3) nanoparticles because good separation in the absorption and emission bands of the material and it fluoresces in the visible to near-infrared range. Terbium ions were added to a LaF3 crystal because of their distinct visible green …


Surface Characterization And Electrochemical Behavior Of Colloidal Particles, Cinta Pepin Aug 2010

Surface Characterization And Electrochemical Behavior Of Colloidal Particles, Cinta Pepin

All Theses

There is an ongoing interest in research focused on developing polymeric organic-light-emitting-devices (OLED) to replace inorganic devices. Compared to inorganic devices, OLEDs could present better properties such as higher efficiency, lower cost and simpler device fabrication. In an attempt to get a device with high efficiency, the hole transporting group and the electron transporting group were combined into a polymer to make an individual 'particle device'. The idea was to create a polymer particle containing both charge transporting moieties via emulsion polymerization. In this presentation, different techniques will be described that were used to determine the stability and the surface …


Ultracapacitor Heavy Hybrid Vehicle: Model Predictive Control Using Future Information To Improve Fuel Consumption, Seneca Schepmann Aug 2010

Ultracapacitor Heavy Hybrid Vehicle: Model Predictive Control Using Future Information To Improve Fuel Consumption, Seneca Schepmann

All Theses

This research is concerned with the improvement in the fuel economy of heavy transport vehicles through the use of high power ultracapacitors in a mild hybrid electric vehicle platform. Previous work has shown the potential for up to 15% improvement on a hybrid SUV platform, but preliminary simulations have shown the potential improvement for larger vehicles is much higher.
Based on vehicle modeling information from the high fidelity, forward-looking modeling and simulation program Powertrain Systems Analysis Toolkit (PSAT), a mild parallel heavy ultracapacitor hybrid electric vehicle model is developed and validated to known vehicle performance measures. The vehicle is hybridized …


State Estimation For Diffusion Systems Using A Karhunen-Loeve-Galerkin Reduced-Order Model, Justin Mattimore Aug 2010

State Estimation For Diffusion Systems Using A Karhunen-Loeve-Galerkin Reduced-Order Model, Justin Mattimore

All Theses

This thesis focuses on generating a continuous estimate of state using a small number of sensors for a process modeled by the diffusion partial differential equation(PDE). In biological systems the diffusion of oxygen in tissue is well described by the diffusion equation, also known by biologists as Fick's first law. Mass transport of many other materials in biological systems are modeled by the diffusion PDE such as CO2, cell signaling factors, glucose and other biomolecules.
Estimating the state of a PDE is more formidable than that of a system described by ordinary differential equations (ODEs). While the state variables of …


Investigating Pre-Breakdown Currents In Polymer Tantalum Capacitors, Githin Alapatt Aug 2010

Investigating Pre-Breakdown Currents In Polymer Tantalum Capacitors, Githin Alapatt

All Theses

Poly(3,4-ethylenedioxythiophene) (PEDOT), a conducting polymer, has been used since
the 1990s for the cathode of tantalum capacitors, which have a tantalum anode, and a layer of
tantalum pentoxide as the dielectric. Such capacitors are referred to as Polymer Ta capacitors.
The first method, an in situ polymerization technique, used to deposit the polymer resulted in
capacitors with a significant leakage current and breakdown voltages near 50 V. The second
method, a pre-polymerization (pre-poly) technique, resulted in capacitors that have a much lower
leakage current and a higher breakdown voltage than the in situ capacitors.
In this thesis, an accurate measurement …


Parametric Instabilities For Vibratory Energy Harvesting Under Harmonic, Time-Varying Frequency, And Random Excitations, Christopher Stabler Aug 2010

Parametric Instabilities For Vibratory Energy Harvesting Under Harmonic, Time-Varying Frequency, And Random Excitations, Christopher Stabler

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This effort investigates and evaluates the prospect of using parametric instabilities for vibratory energy harvesting. To that end, we consider a parametrically-excited piezoelectric cantilever beam and study its performance as an energy harvester under i) fixed-frequency harmonic excitations, ii) time-varying frequency excitations, and iii) band-limited Gaussian noise. In the case of fixed-frequency excitations, we use the Method of Multiple Scales to obtain approximate analytical expressions for the steady-state response amplitude and instantaneous output power in the vicinity of the first principle parametric resonance. We show that the electromechanical coupling and load resistance play an important role in determining the output …


Electromechanical Modeling And Analysis Of A Self-Excited Micro-Power Generator, Amin Bibo Aug 2010

Electromechanical Modeling And Analysis Of A Self-Excited Micro-Power Generator, Amin Bibo

All Theses

Micro-power generators (MPGs) are compact, scalable, and low-maintenance energy harvesting devices that capture and transform wasted ambient energy into electricity.
Such devices, which are currently being researched as a possible replacement for batteries, can act as a power source to maintain and allow autonomous operations of
remote low-power consumption sensors. This thesis introduces a novel MPG which transforms wind energy into electricity via wind-induced self-excited oscillations
of piezoelectric cantilever beams. The operation concept of the device is simple: similar to music-playing harmonica that create tones via oscillations of reeds when
subjected to air blow, the proposed device uses flow-induced self-excited …


Infrared Thermography And Ultrasonic Inspection Of Adhesive Bonded Structures, Overview And Validity, Suhas Vedula Aug 2010

Infrared Thermography And Ultrasonic Inspection Of Adhesive Bonded Structures, Overview And Validity, Suhas Vedula

All Theses

The work focuses on establishing a relationship between two different techniques of Nondestructive testing, namely Infrared Thermography and Ultrasonic Inspection. The integration of the two testing techniques is done with an expectation to achieve accurate characterization and determination of internal defects in adhesive bonded structures.
Experiments are done on sandwich samples with defects using various ultrasonic testing methods like pulse-echo and immersion techniques. The results thus obtained are documented and location of the defects is marked. The same samples are then tested using Infrared thermography to visualize the defects.
The results obtained by both the methods are compared to check …


Fuzzy Logic Approach To Stability Control, Jeffery Anderson Aug 2010

Fuzzy Logic Approach To Stability Control, Jeffery Anderson

All Theses

Traditional Electronic Stability Control (ESC) for automobiles is usually accomplished through the use of estimated vehicle dynamics from simplified models. Starting with the conventional two degree-of-freedom vehicle model, one can estimate the vehicle states from the driver steering input. From this estimate, vehicle sideslip angle can be found and this is generally used with a threshold value to initiate a control action. The input/output relationship of the model depends heavily on the accuracy of the parameters used and various means to correct model inaccuracies. Specifically, these models depend on the tire cornering stiffness which is prone to change with age …


Hemocompatibility And Endothelialization Of Elastin And Collagen Scaffolds: The Role Of Plasma Proteins, Shear Stress And Integrins, Nithya Swaminathan Aug 2010

Hemocompatibility And Endothelialization Of Elastin And Collagen Scaffolds: The Role Of Plasma Proteins, Shear Stress And Integrins, Nithya Swaminathan

All Theses

Cardiovascular diseases are the leading cause of death worldwide as reported by the World Health Organization. Biomaterials have been extensively used in blood-contacting applications as heart valves, stents, grafts and catheters. However failure due to thrombosis hinders the long term patency and potential of these devices. Purified elastin scaffolds derived from porcine arteries as potential vascular graft materials are being investigated in our laboratory. In this study, we investigated the influence of factors such as shear stress and the presence of plasma proteins on the platelet response, and endothelial cell retention on purified elastin scaffolds to evaluate their hemocompatibility.

Elastin …


Automation Of Non-Destructive Testing Techiniques Used For Finding Defects, Bhanu Singh Aug 2010

Automation Of Non-Destructive Testing Techiniques Used For Finding Defects, Bhanu Singh

All Theses

This master thesis focuses on the automation and fusion of non-destructive testing methods. The research includes the fusion of non-destructive testing methods done with infrared micro-bolometer and ultrasonic transducers. A control system which utilized mechanical, electrical, electronic systems and computer aided technologies was developed. Conveyor belt system, PLC (programmable logic controller), XYZ mechanism and different sensors were utilized to automate the process of capturing images and a communication link was set up between thermal camera and system that controls the ultrasonic testing apparatus, to integrate the two techniques. The test results from the thermal camera were utilized in ultrasonic testing. …


Sensor Based Nitrogen Management For Cotton Production In Coastal Plain Soils, Wesley Porter Aug 2010

Sensor Based Nitrogen Management For Cotton Production In Coastal Plain Soils, Wesley Porter

All Theses

The main objective of this four year study was to develop, refine, and employ sensor-based algorithims to determine the mid season nitrogen requirements for production of irrigated and dryland cotton (Gossypium hirsutum L.) in Coastal Plains soils. The secondary objective of the project was to develop and test equipment for variable rate application of nitrogen to commerical cotton fields utilizing the developed algorithim. Two different production fields at Clemson's Edisto Research and Education Center near Blackville, SC were used. One field, equiped with an overhead irrigation system, was used during the 2007 and 2010 production seasons to develop the algorithm …


Modeling And Optimization Of A Plug-In Hybrid Electric Vehicle, Venkat Vijay Kishore Turlapati Aug 2010

Modeling And Optimization Of A Plug-In Hybrid Electric Vehicle, Venkat Vijay Kishore Turlapati

All Theses

Today, the world is faced with a situation where new technologies have to be developed to decrease the dependence on natural non-renewable resources. Each day, as the demand for non-renewable resources increases, it puts great pressure on the scientific fraternity to develop new technologies that are aimed at reducing this dependence.
Today's road traffic plays a major part in the energy consumption worldwide. Hence it is imperative that we develop environmentally friendly solutions to this problem that arises in the transportation sector. Hybrid vehicle is one of the alternatives that can be seen as a viable solution to this energy …


Induction Assisted Thermography For Inspection Of Micro Defects On Sheet Metals, Sree Pamidi Aug 2010

Induction Assisted Thermography For Inspection Of Micro Defects On Sheet Metals, Sree Pamidi

All Theses

The work focuses on Induction assisted Thermography as a non-contact and non-destructive method of Inspecting micro defects on sheet metals used for making automotive body panels. Induction heating as a source of excitation to elevate the temperatures of sheet metals for uniform heating and detect ability of the defect is the main objective of the study.
Experiments are done on sheet metal samples with defects using excitation techniques like Pulse and Electromagnetic Induction. The thermal images obtained from the infrared camera are used to quantitatively analyze the detect ability of defects on sheet metals. The limitations of using Pulse technique …


Detecting Piecewise Linear Networks Using Reversible Jump Markov Chain Monte Carlo, Akshay Apte Aug 2010

Detecting Piecewise Linear Networks Using Reversible Jump Markov Chain Monte Carlo, Akshay Apte

All Theses

This work proposes a piecewise linear network model to approximate structures observed in an image. An energy function is used to capture the characteristics of the structure. The energy function consists of two parts: the prior energy term and the data energy term. The prior energy term is calculated using prior information about the structures of interest. The data energy term is calculated using observations made from the image. The energy function is minimized using Reversible Jump Markov Chain Monte Carlo (RJMCMC) to get the approximate centerline of the structure. The algorithm was tested on a database of $150$ images …


Design Method Development For The Design Of Traction Systems, Avinash Kolla Aug 2010

Design Method Development For The Design Of Traction Systems, Avinash Kolla

All Theses

The objective of this research is to develop a design method for rapid exploration of traction concepts primarily for off-road vehicles. Different approaches available to achieve this objective are discussed and compared, such as computational, analytical, and physical methods. Computational approaches are based on simulations performed using Finite Element Method (FEM), Discrete Element Method (DEM), and combined Finite Element-Discrete Element (FE-DE) methods. Analytical approaches are based on closed form mathematical models developed by previous researchers based on the theory of plasticity. Physical approaches include fabrication and testing of prototypes at different levels of abstraction. This thesis compares these different approaches …


The Effects Of Physical Factors On The Adsorption Of Synthetic Organic Compounds By Activated Carbons And Activated Carbon Fibers, Hatice Kose Aug 2010

The Effects Of Physical Factors On The Adsorption Of Synthetic Organic Compounds By Activated Carbons And Activated Carbon Fibers, Hatice Kose

All Theses

Activated carbons (ACs) and activated carbon fibers (ACFs) have been extensively used for the removal of synthetic organic compounds (SOCs) that have been found to be toxic, carcinogenic, mutagenic or teratogenic. Adsorption of these compounds on ACs and ACFs are controlled by both physical factors and chemical interactions, which depend on the characteristics of the adsorbent (surface area, pore size distribution (PSD), and surface chemistry), the nature of the adsorbate (molecular weight and size, functional groups, polarity, solubility), and the condition of the background solution (pH, temperature, presence of competitive solutes, ionic strength). Since there are several mechanisms that can …


Remote Usability Testing - A New Approach Facilitated By Virtual Worlds, Kapil Chalil Madathil Aug 2010

Remote Usability Testing - A New Approach Facilitated By Virtual Worlds, Kapil Chalil Madathil

All Theses

Synchronous remote usability testing, involves a facilitator conducting a usability test in real time, interacting with a participant who is remote. This study proposes a new methodology for conducting these studies using a three-dimensional virtual world, Wonderland, and compares it with two other commonly used synchronous usability test methods: the traditional lab approach and WebEx, a web-based conferencing and screen sharing approach.
The study involved 48 participants in total, 36 test subjects and 12 test facilitators. These 36 were equally divided among the three environments with the 12 test facilitators being paired with one participant in each of the environments. …


Influence Of Iso-Structural Substitutions On Properties Of Ge(As,Sb)(S,Se) Glasses, Guillaume Guery Aug 2010

Influence Of Iso-Structural Substitutions On Properties Of Ge(As,Sb)(S,Se) Glasses, Guillaume Guery

All Theses

Chalcogenide glasses possess exceptional infrared transparency, large non-linear refractive indexes and low phonon energies, making them good candidates for infrared optical applications. Previous studies in the Ge-Sb-S glass system have shown an increase in the nonlinear refractive index with an iso-structural substitution of two- coordinated selenium (Se) for sulphur (S) and variation of other physical properties with substitution of other iso-structural species such as three-coordinated arsenic (As) for antimony (Sb). The role of such iso-structural exchange on properties important to the thermo-, visco- and mechanical attributes of glasses in the Ge-As/Sb-S/Se system has not been thoroughly evaluated and form the …


Evaluating Transit Systems In A University Environment The Clemson University Case Study, Katerina Bartman Aug 2010

Evaluating Transit Systems In A University Environment The Clemson University Case Study, Katerina Bartman

All Theses

With the economy in a slow recovery, enrollment in higher education is
increasing. This means that universities across the country must accommodate these new students, their vehicles, and local transportation needs. Campus setting and ambiance is a treasured quality on a university campus resulting in the approval of additional surface lots and parking garages being difficult or restricted. To combat the increased number of single occupancy vehicles, universities are developing and encouraging the use of multimodal transportation by providing pedestrian, bicycle, and public transportation facilities along with providing users with the information necessary to make the optimal modal choice (Boyles, …


Alkali Silica Reaction Under The Influence Of Chloride Based Deicers, Purvi Desai Aug 2010

Alkali Silica Reaction Under The Influence Of Chloride Based Deicers, Purvi Desai

All Theses

Highways form the backbone of transportation in United States. As a result, issues related to distress in pavements and use of chemicals on pavement forms one of the major focus areas of highway agencies. One of the forms of distress in concrete pavements is Alkali silica reaction (ASR). External source of alkalis in the form of deicing chemicals play a key role in accelerating ASR. Sodium chloride or Rock salt is one of the oldest forms of deicers. Several research studies have been done on ASR under the influence of sodium chloride and calcium chloride. Limited information is available on …