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Evaluation Of Engineering Plastic For Rollover Protective Structure Mounting, Robert Stephen Comer
Evaluation Of Engineering Plastic For Rollover Protective Structure Mounting, Robert Stephen Comer
Masters Theses
The agricultural industry has one of the highest fatality rates of any industry in the U. S. This death rate is largely due to deaths caused by roll over accidents while on agricultural vehicles. The addition of a Rollover Protective Structure (ROPS) has aided in lowering these high fatality rates on full-size tractors. Studies have shown that death rates have been reduced by as much as 98% with the addition of rollover protective structures. However, a large number of older tractors still do not utilize a ROPS. This is due to the difficulty of designing and creating a mounting structure. …
Comparison Of Microscopic Modalities For The 3d Model Reconstruction Of Nanodevices, Christopher Robert Kammerud
Comparison Of Microscopic Modalities For The 3d Model Reconstruction Of Nanodevices, Christopher Robert Kammerud
Masters Theses
As manufacturing capabilities push nanotechnology to smaller and smaller scales, novel inspection schemes must be developed to ensure product quality. The objective of our research was to implement, refine, and compare 3D reconstruction algorithms that could aid manufacturers in their ability to visualize and inspect nanodevices. Data was collected from three different microscopes: the atomic force microscope (AFM), the scanning electron microscope (SEM), and the laser scanning confocal microscope (LSCM). For each of these microscopes, a specific algorithm was implemented to generate 3D models from the raw microscope data. Scans from the AFM microscope give range information similar to laser …
A Statistical Based Model To Manage Perishable Goods Within A Cold Supply Chain, Amanda Rhiana Hicks
A Statistical Based Model To Manage Perishable Goods Within A Cold Supply Chain, Amanda Rhiana Hicks
Masters Theses
"Cold chain" management, the management of a temperature sensitive supply chain, has its own particular set of logistical challenges and issues when compared to a non-temperature sensitive supply chain. Current supply chain management techniques and tools that are utilized today in industry do not take this unique set of challenges into account. This thesis will focus on how using a model that has been built upon the theories of statistical process control techniques that does take the challenges into account, when monitoring and evaluating in-transit shipment of perishable goods throughout the cold supply chain, can assist in continuously improving the …
Experimental Aerodynamic Analysis Of A Wing-Flap System With Delta Vortex Generators, Charles Roy Mcconnell
Experimental Aerodynamic Analysis Of A Wing-Flap System With Delta Vortex Generators, Charles Roy Mcconnell
Masters Theses
The principle idea upon which the use of vortex generators (VGs) is based has been to control flow separation. The characteristic of VGs has been used to improve lift and alter the stall characteristics of aircraft and has been a relatively common practice for many years. Due to the seemingly limitless range of VG geometries and arrangements, which are largely dependant upon the desired aerodynamic performance, there has been a broad investigation into VG application.
The purpose of this experimental investigation has been to collect data to be used to establish the effects of various delta shaped vortex generators (delta-VGs) …
Temperature Control Of The Online Rheological Sensor, Larry Scott Spencer
Temperature Control Of The Online Rheological Sensor, Larry Scott Spencer
Masters Theses
Rheometers are devices that can be used to measure the rheological properties of polymers. Online rheometers test for rheological properties during a polymer process. Real-time rheological data would eliminate any time delays that accompany off-line rheometers and would provide the feedback information needed for tighter polymer process control. A real-time control system would eliminate the need for an offline rheometer to analyze polymer product properties, thus saving both time and money.
The Online Rheological Sensor was used to estimate the shear and elongational viscosities of a polymer from measured variables during processing. The Online Rheological Sensor was mounted on a …
Biomimetic Membranes Realized With Arrays Of Carbon Nanofibers, Eric Hullander
Biomimetic Membranes Realized With Arrays Of Carbon Nanofibers, Eric Hullander
Masters Theses
A microfluidic device with imbedded nanoporous membranes, constructed using a novel nanostructured material, was designed, built, modeled, and tested. The membranes were shown to be modular, and by adsorbing monodisperse latex spheres to the fibrous membrane, the pore size could be controlled. A mathematical model of the device was developed based on several existing fluidic models for transport through fibrous materials, and an image processing algorithm was designed to extract the hydrodynamic properties of the device from a series of scanning electron micrographs based on the existing hydrodynamic models. A series of experiments were performed using fluorescent microscopy to quantify …
Enhancing System-On-Chip Verification Using Embedded Test Structures, Wei Jiang
Enhancing System-On-Chip Verification Using Embedded Test Structures, Wei Jiang
Masters Theses
In this project, we designed and implemented a System-on-Chip platform with embedded test structures. The baseline platform consists of a Leon2 CPU, AMBA on-chip bus, and an Advanced Encryption Standard decryption module. Reconfigurable test logic blocks were embedded to form the test structure that can be used in post-silicon debug and verification.
The System-on-Chip platform was designed at the register transistor level and implemented in an 180nm CMOS process. Test logic instrumentation was done with DAFCA, Inc. (Design Automation for Flexible Chip Architecture) pre-silicon tools. The design was then synthesized using the Synopsys Design Compiler and placed and routed using …
A Numerical Study Of Curved Labyrinth Seals For Steam Turbines, Sricharan Kishore Ayyalasomayajula
A Numerical Study Of Curved Labyrinth Seals For Steam Turbines, Sricharan Kishore Ayyalasomayajula
Masters Theses
A numerical experiment has been conducted to study and evaluate the structural behavior of newly designed labyrinth seals. Structural analysis was performed to understand, evaluate and compare new seals with a baseline straight seal that is typical of commonly used seals in steam turbines. New configurations of labyrinth seal knives were developed for use in steam turbines [17]. The main objective of this study is to develop a better understanding of selected various labyrinth seals that may be configured to minimize the steam leakage and reduce seal interactions with the shaft. Computational fluid dynamic modeling of the various configurations, from …
Flight Testing Quadeye The First Night Vision Helmet Mounted Cueing System For Fixed Wing Jet Aircraft, Timothy Ghannon Burton
Flight Testing Quadeye The First Night Vision Helmet Mounted Cueing System For Fixed Wing Jet Aircraft, Timothy Ghannon Burton
Masters Theses
In 2002 the United States Navy introduced helmet mounted cueing systems (HMCS) into tactical jet operations. As aircrews have become more reliant on their HMCS the requirement for a night vision capable cueing system has risen to the forefront of HMCS technology. One proposed solution to this requirement was Quadeye. Quadeye is a wide-angle (100deg field of view) four cathode-ray tube system with injected Joint Helmet Mounted Cueing video. The Navy flew 8 evaluation sorties from March to August 2005, in the F-18 A-F fighter aircraft. The goal of this limited scope effort was to answer four questions:
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Does the …
Viscosity Measurement Technique By Merging Liquid Drops Aboard The International Space Station, Daniel Aaron Lehman
Viscosity Measurement Technique By Merging Liquid Drops Aboard The International Space Station, Daniel Aaron Lehman
Masters Theses
The efforts reported in this thesis has been to analyze the data from two "Fluid Merging Viscosity Measurement" experiments in order to validate this as a viable method for measuring the viscosity of fluids with known surface tensions. This method involves simultaneously using a numerical analysis code and experimental data to produce matching curves of contact radius versus time and from that a determination of viscosity. Two experiments that were performed, used different liquids (glycerin and 125 Poise silicon oil) and different size ratios between the two drops ( 1 to 1 and O. 3 3 to 1 respectively). The …
Topology Optimization Of Carbon Nanotube Reinforced Polymer Damping Structures, Seshadri Mohan Varma Damu
Topology Optimization Of Carbon Nanotube Reinforced Polymer Damping Structures, Seshadri Mohan Varma Damu
Masters Theses
Topology optimization has been successfully used for improving vibration damping in constrained layer damping structures. Reinforcing carbon nanotubes in a polymer matrix greatly influence the mechanical properties of the polymer. Such nanotube-reinforced polymers (NRP) can be used to further enhance the damping properties of the constrained layer structures. In this work, topology optimization is performed on constrained damping layer structures using NRP in order to maximize the loss factor for the first resonance frequency of the base beam. In addition to the material fractions of the NRP and elastic material, the volume fraction of the nanotubes in the polymer is …
Optimization Of Dsss Receivers Using Hardware-In-The-Loop Simulations, Balbir Kaur Dhillon
Optimization Of Dsss Receivers Using Hardware-In-The-Loop Simulations, Balbir Kaur Dhillon
Masters Theses
Over the years, there has been significant interest in defining a hardware abstraction layer to facilitate code reuse in software defined radio (SDR) applications. Designers are looking for a way to enable application software to specify a waveform, configure the platform, and control digital signal processing (DSP) functions in a hardware platform in a way that insulates it from the details of realization.
This thesis presents a tool-based methodolgy for developing and optimizing a Direct Sequence Spread Spectrum (DSSS) transceiver deployed in custom hardware like Field Programmble Gate Arrays (FPGAs). The system model consists of a tranmitter which employs a …
Effect Of Hydrogenon On Mechanical Behavior Of A Zircaloy-4 Alloy, Elena Garlea
Effect Of Hydrogenon On Mechanical Behavior Of A Zircaloy-4 Alloy, Elena Garlea
Masters Theses
Hydride formation is one of the main degradation mechanisms of zirconium alloys in hydrogen-rich environments. When sufficient hydrogen is present, zirconiumhydride precipitates can be formed. Cracking of the brittle hydrides near a crack tip can initiate the growth of a crack leading to the premature failure of the material. Hydride formation is believed to be enhanced by the presence of residual or applied stresses. Therefore, the increase in the stress field ahead of a crack tip may promote precipitation of additional hydrides. In order to verify these phenomena, the effect of internal stresses on the zirconium-hydride-precipitate formation, and in turn, …
“Design And Verification Of A Reusable Self-Reconfigurable Gate Array Architecture, Gabriel Cozmin Chereches
“Design And Verification Of A Reusable Self-Reconfigurable Gate Array Architecture, Gabriel Cozmin Chereches
Masters Theses
This thesis presents the design and verification of a Self-Reconfigurable Gate Array architecture (SRGA-UT) created for reuse, and available with a step-by-step tutorial and comprehensive documentation. The original SRGA [1], created at the University of Southern California, is an innovative architecture for a reconfigurable device that allows single cycle context switching and single cycle random access to a unified on-chip configuration/data memory. The key architecture that enables the above two features is the use of a mesh of trees based interconnect with logic cells and memory blocks at the leaf nodes and identical switches at the parent nodes.
The SRGA-UT …
A Dynamic Ampacity Model For The Testing Of Advanced Conductors, Matthew Benjamin Sooter
A Dynamic Ampacity Model For The Testing Of Advanced Conductors, Matthew Benjamin Sooter
Masters Theses
Advanced Conductors are an intriguing new technology that promises to help the utility industry increase the transmission capacity available in the United States. Manufacturers of advanced conductors promise double the current carrying capacity of normal Aluminum Clad Steel Reinforced conductor through a combination of increased thermal limits and decreased thermal elongation.
This thesis will outline a control developed for the Power Line Conductor Accelerated Test Facility at Oak Ridge National Laboratory. This custom facility is designed for the testing and rapid aging of advanced overhead conductors as part of a U.S. Department of Energy initiative to assist the development and …
An Experimental Evaluation Of The Constant Β Relating The Contact Stiffness To The Contact Area In Nanoindentation, Jeremy Harper Strader
An Experimental Evaluation Of The Constant Β Relating The Contact Stiffness To The Contact Area In Nanoindentation, Jeremy Harper Strader
Masters Theses
Measurements of mechanical properties by nanoindentation with triangular pyramidal indenters like the Berkovich rely heavily upon the relationship between the contact stiffness, S, the contact area, A, and the reduced elastic modulus, Er . This relationship is often written in the form: S = 2βEr(A/π)1/2, where βis a constant that depends on the geometry of the indenter. Although the most common values for βused in experimental measurements are 1.000 and 1.034, various theoretical analyses have yielded values as small as 1.00 or as large as 1.2, depending on the assumptions made to model the deformation. Here the most appropriate …
Propeller Development Process: Conflict And Cooperation Between The Department Of Defense And Civil Aviation, Nathan Grant Neblett
Propeller Development Process: Conflict And Cooperation Between The Department Of Defense And Civil Aviation, Nathan Grant Neblett
Masters Theses
The purpose of this thesis was to compare and contrast the acquisition of the Electronic Propeller Control System through both the Department of Defense and Civil Aviation processes controlled by the Federal Aviation Administration (FAA). The author was a planner and participant in the Department of Defense (DoD) process. Information about the Civil Aviation process was obtained via email and telephone communication with participants, some of whom aided both processes.
Strong similarities existed in system design and prototype manufacture for both processes. A large portion of developmental flight test was similar, if not identical. In particular, both the DoD and …
Bio-Derived Fuels For Hybrid Rocket Motors, Joshua David Scholes
Bio-Derived Fuels For Hybrid Rocket Motors, Joshua David Scholes
Masters Theses
Two bio-derived fuels have been successfully tested in a laboratory scale hybrid rocket combustion chamber located at the University of Tennessee, Knoxville. Pure lard soaked in an open cell sponge matrix and beeswax were both tested using gaseous oxygen as the oxidizer. Given similar testing conditions, these fuels exhibit higher regression rates than the common hybrid rocket propellant HTPB (hydroxyl-terminated polybutadiene), thus overcoming one of the main shortcomings of hybrid rocket fuels. These fuels also have similar or higher regression rates than paraffin-based fuels recently tested by a Stanford University/NASA Ames team. Measured thrusts ranged from 20-140 Newtons, and calculated …
An Experimental Study Of Axisymmetric Cavity Oscillations In Low Speed Incompressible Flow, Jeremy David Brice Smith
An Experimental Study Of Axisymmetric Cavity Oscillations In Low Speed Incompressible Flow, Jeremy David Brice Smith
Masters Theses
This study is the latest increment of an ongoing research effort at the University of Tennessee Space Institute with the goal of accomplishing a greater understanding of cavity instabilities and or making use of the instabilities to amplify their effects on the flows. An experimental procedure was designed to examine the unsteady pressure pulses that occur when an incompressible fluid (water) flows through an axisymmetric cavity. The length to depth ratios (L/D) examined ranged from about 0.69 to about 6.2, and the average flow Reynolds numbers ranged from 0 to 1.2 million.
Results show that large amplitude oscillations are generated …
Comparative Properties Of Polymers Guiding The Development Of An Abdominal Aorta Model, Benjamin Michael Lamie
Comparative Properties Of Polymers Guiding The Development Of An Abdominal Aorta Model, Benjamin Michael Lamie
Masters Theses
Hemodynamics, the study of the forces involved in the circulation of blood, is an area that researchers have approached in various manners for many years. The study of how blood flows through arteries and veins as well as the effect of the composition of the blood has been defined and thoroughly characterized in past studies. Although in-depth studies have been performed on the flow characteristics of blood, most often the observations are made as the fluid flows through tubes composed of some rigid material. It is well known that the arteries and veins have a layered histology that show varying …
A Study Of Material Properties And Relevant Microstructure Parameters That May Influence The V50 Ballistic Limit Velocity Of Composite Ceramics, Adolphus Mcdonald
A Study Of Material Properties And Relevant Microstructure Parameters That May Influence The V50 Ballistic Limit Velocity Of Composite Ceramics, Adolphus Mcdonald
Masters Theses
The purpose of this research is to evaluate, compare, and correlate the microstructure and mechanical properties of a selected group of ceramic armor samples to the V50 ballistic limit velocity. This study is to identify any relation between the desired material properties and the relevant microstructure parameters that significantly influence the ballistic limit velocity. The ceramic materials, silicon carbide and boron carbide, were produced and provided by five foreign companies. These companies were under contract by the United States Army, Research, Development, and Engineering Command to provide ceramic armor for comparative testing and material evaluation.
Ballistic testing was carried …
Approaches For Autonomous Vehicles In Civil Airspace: Giving Sight To The Blind, Nicholas Scott Hardman
Approaches For Autonomous Vehicles In Civil Airspace: Giving Sight To The Blind, Nicholas Scott Hardman
Masters Theses
The growing prevalence of unmanned aerial vehicles (UAVs) brings great potential for public benefit, but in order to fly in civil airspace UAVs must avoid traffic without the benefit of an onboard human. Developing this capability presents many system integration challenges.
This report examines the integration of automated detect, see, and avoid (DSA) systems on aircraft. For context, the need for UAV operations is reviewed. The report then examines how DSA fits into the entire framework for aviation safety. The research, test results, and conclusions that follow provide the necessary information to decide:
• how to test and evaluate new …
The Development Of Qualification Standards For Cast Super Duplex Stainless Steel (2507 Wrought Equivalent), Vasudevan Hariharan
The Development Of Qualification Standards For Cast Super Duplex Stainless Steel (2507 Wrought Equivalent), Vasudevan Hariharan
Masters Theses
The objective of the program is to determine the suitability of ASTM A923 “Standard Test methods for Detecting Detrimental Intermetallic Phase in Wrought Duplex Austenitic-Ferritic Stainless Steels” for 25 Cr Cast Super Duplex Stainless Steels (ASTM A890-5A).
Different tests were carried out on the materials procured from various steel foundries as stated in the ASTM A923. The foundries were designated as Foundry A, B, C and D. All the materials were foundry solution annealed. Materials from Foundry D were solution heat treated at The University of Tennessee also and then they were subjected to heat treatment schedule which was derived …
Design Of A Novel Reluctance Motor For Industrial Applications, Weston Clute Johnson
Design Of A Novel Reluctance Motor For Industrial Applications, Weston Clute Johnson
Masters Theses
A novel reluctance motor topology, termed the Johnson-Currie Reluctance Motor (JCRM), has been developed and described in this thesis. The JCRM topology and analysis is based upon the traditional switched reluctance motor (SRM) topology although there are significant modifications.
The flux path of the JCRM topology is such that it passes through the rotor and stator in three-dimensions. This topology with three dimensional flux paths allows for the removal of discrete stator windings giving rise to vastly superior maintance to the traditional SRM and arguably to most electric motors. In addition, the usage of three-dimensions for flux paths gives rise …
Synthesis, Microstructure, And Mechanical Behavior Of Fe-Cu Composites, Jin-Woo Jeon
Synthesis, Microstructure, And Mechanical Behavior Of Fe-Cu Composites, Jin-Woo Jeon
Masters Theses
The synthesis, microstructure, and mechanical properties of ball-milled nanocrystalline (nc) Fe powder and immiscible Fe-Cu alloy composites are investigated in this thesis. Experimental approaches are described for the characterization of the grain size and hardness of nc Fe powders and the internal stress state of bulk Fe-Cu alloy composites are presented.
The grain size measurements of ball-milled Fe powders obtained from the XRD line broadening analysis (15 nm) and TEM observation (18 nm) showed good agreement between two results. From the nanoindentation tests, the hardness values of the ball-milled Fe powders were increased from 3.5 to 10.5 GPa as the …
Physical Layer Simulation Study For The Co-Existence Of Wlan Standards, Chad Joseph Kiger
Physical Layer Simulation Study For The Co-Existence Of Wlan Standards, Chad Joseph Kiger
Masters Theses
Interference is a prime factor that limits the performance of devices within the 2.4 GHz ISM Band. Due to the ISM Band being unlicensed and free to all users, there is an abundance of devices within this frequency range. The three most prominent of such devices used for data communication consist of Bluetooth, Wifi, and Zigbee. In order to understand whether these three protocols can co-exist with each other, a physical layer system model will be developed for each protocol. These systems models will be combined and their interaction with each other examined to determine the effects of the interference …
Universal Geometric Camera Calibration With Statistical Model Selection, Chistopher Paul Broaddus
Universal Geometric Camera Calibration With Statistical Model Selection, Chistopher Paul Broaddus
Masters Theses
We propose a new universal camera calibration approach that uses statistical information criteria for automatic camera model selection. It requires the camera to observe a planar pattern from different positions, and then closed-form estimates for the intrinsic and extrinsic parameters are computed followed by nonlinear optimization. In lieu of modeling radial distortion, the lens projection of the camera is modeled, and in addition we include decentering distortion. This approach is particularly advantageous for wide angle (fisheye) camera calibration because it often reduces the complexity of the model compared to modeling radial distortion. We then apply statistical information criteria to automatically …
Characterizing Turbulence Structure Along Woody Vegetated Banks In Incised Channels: Implications For Stream Restoration, Frank James Dworak
Characterizing Turbulence Structure Along Woody Vegetated Banks In Incised Channels: Implications For Stream Restoration, Frank James Dworak
Masters Theses
The impacts of urbanization have modified natural watersheds and stream hydraulic, hydrologic, and geomorphic processes that have lead to geomorphic and ecological disturbances in natural stream systems. These alterations have resulted in channel incision and the loss of channel-scale hydraulic characteristics responsible for initiating and maintaining pool-riffle bedforms, which are capable of supporting diverse biological stream ecosystems. Through the use of FLOW-3D, a 3-dimensional computational fluid dynamics model, three scenarios of an urban, incised, and channelized stream were simulated to characterize the turbulent, hydraulic structure during bankfull discharge. The simulations were conducted with trees inhibiting bankfull flow (representing the channel’s …
Hardware Design And Implementation Of Role-Based Cryptography, Scott Edward Fields
Hardware Design And Implementation Of Role-Based Cryptography, Scott Edward Fields
Masters Theses
Traditional public key cryptographic methods provide access control to sensitive data by allowing the message sender to grant a single recipient permission to read the encrypted message. The Need2Know® system (N2K) improves upon these methods by providing role-based access control. N2K defines data access permissions similar to those of a multi-user file system, but N2K strictly enforces access through cryptographic standards. Since custom hardware can efficiently implement many cryptographic algorithms and can provide additional security, N2K stands to benefit greatly from a hardware implementation. To this end, the main N2K algorithm, the Key Protection Module (KPM), is being specified in …
A Comparison Of The Sensor Brick Concept As A Modular System Architecture To The Realtime Control System As The Operational Architecture, James Robert Wilson
A Comparison Of The Sensor Brick Concept As A Modular System Architecture To The Realtime Control System As The Operational Architecture, James Robert Wilson
Masters Theses
This thesis describes the application of modular design into an intelligent mobile robotic system. The Sensor Brick System, a mobile robotic system infused with artificial intelligence, is derived through the concept and application of modular design. Modular design drives the system’s characterization by defining, identifying and selecting the essential composite of sub-systems that form the system architecture. The principles of modular design designate grouping the technologies into modules that facilitate maintenance of the system components and allow the rapid integration of future technological developments. Developing the operational control of the system requires an examination and comprehension of the theories of …