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 …

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

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 …

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 …

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 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 …

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 …

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 …

Automated Analysis Of Fluorescent Microscopic Images To Identify Protein-Protein Interactions, Sankar Venkataraman

Masters Theses

The identification and confirmation of protein interactions significantly challenges the field of systems biology and related bio-computational efforts. The identification of protein-protein interactions along with their spatial and temporal localization is useful for assigning functional information to proteins. Fluorescence microscopy is an ideal method for assessing protein localization and interactions as a number of techniques and reagents have been described. Historically, data sets obtained from fluorescence microscopy have been analyzed manually, a process that is both time consuming and tedious. The development of an automated system that can measure the location and dynamics of interacting proteins inside a live cell …

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 …

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 …

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) …

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 …

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 …

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 …

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 …

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:

1. Does the …

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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 …

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. …

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 …

Linking Channel Stability And Bed Sediment Characteristics To Biological Integrity In Tennessee Ridge And Valley Streams, Kelley H. Williams

Masters Theses

Streambed sedimentation has plagued waterways since the beginning of civilization, whether as a natural flow process or human disturbances on the landscape in more recent times. Due to the continual degradation in the quantity and diversity of aquatic organisms within streams, the issue has finally surfaced as a significant concern. The need to develop better Total Maximum Daily Load (TMDL) assessment tools to link sediment impairment to biological integrity was the driving force behind this study.

Within the Ridge and Valley Ecoregion, 76 stream reaches were analyzed to investigate the impacts of stability issues and bed sediment characteristics on stream …

Kinetics Of Cellulose Dissolution In N-Methyl Morpholine-N-Oxide And Evaporative Processes Of Similar Solutions, John William Tierney

Masters Theses

The lyocell process is an environmentally friendly process for producing regenerated cellulose fibers, but is not entirely understood. The lyocell process uses the hygroscopic solvent N-methyl morpholine N-oxide (NMMO) to dissolve cellulose; the resulting solution is often termed a lyocell solution [1-4]. It is the objective of this study to better understand the process by which cellulose dissolves and the nature of lyocell solutions. By observing the disappearance of cellulose fibers into the solvent, rate data may be obtained from which kinetic parameters may be developed. Additionally an independent method for determining the concentration of cellulose in lyocell solutions was …

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

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 …

Bench Scale Evaluation Of Dense Ceramic Membranes For Production Of High Purity Hydrogen From Gasification, Binay Kumar Singh

Masters Theses

Gasification for production of hydrogen and other useful gases, has achieved increasing importance in recent years. The reactions involved in gasification are favored at high temperatures and they are also limited by thermodynamic equilibrium. The development of membranes which can separate these gases under gasifier exit gas condition will significantly improve process efficiency and economics and simultaneously provide for the recovery of valuable gases. The availability of a membrane with adequate hydrogen selectivity and good thermal and mechanical stability is the key for the successful application of membrane technology in hydrogen production and separation. This work introduces a special method …

Performance Study Of Hybrid Spread Spectrum Techniques, Yachna Sharma

Masters Theses

This thesis focuses on the performance analysis of hybrid direct sequence/slow frequency hopping (DS/SFH) and hybrid direct sequence/fast frequency hopping (DS/FFH) systems under multi-user interference and Rayleigh fading. First, we analyze the performance of direct sequence spread spectrum (DSSS), slow frequency hopping (SFH) and fast frequency hopping (FFH) systems for varying processing gains under interference environment assuming equal bandwidth constraint with Binary Phase Shift Keying (BPSK) modulation and synchronous system. After thorough literature survey, we show that hybrid DS/FFH systems outperform both SFH and hybrid DS/SFH systems under Rayleigh fading and multi-user interference. Also, both hybrid DS/SFH and hybrid DS/FFH …

Managing The Remaining Service Life Of The T-34c Aircraft, John Howard Rousseau

Masters Theses

The T-34C Airplane has been the primary trainer aircraft of the United States Navy for more than twenty-five years and is reaching the end of its service life. The Navy has delayed the procurement of the replacement T-6A Texan II aircraft for five years, yet does not expect the future training requirements to diminish. This delay in T-6A procurement along with recent observed increases in primary trainer aircraft usage have resulted in the need for the Navy to pay considerable attention to the remaining service life of the T-34C aircraft.

This thesis will discuss the methodology used to determine future …

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 …

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, E_r . 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 …

“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 …