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Water Quality Characterization, Stormwater Analyses, And Statistical Modeling Of Stream Water Quality In The Little Pigeon River Watershed Of The Great Smoky Mountains National Park, James Chadwick Roby

Masters Theses

Scheduled road construction prompted intensive water quality monitoring of the adjacent stream, the Little Pigeon River. Three phases of monitoring was planned to fully assess any impacts construction may have: pre, during, and post construction monitoring. One year of pre-construction monitoring has been completed. Three monitoring sites were installed. Site 1 was below, Site 2 in the middle, and Site 3 above all road construction. Each site had a YSI sonde that measured 15-minute pH, turbidity, conductivity, temperature, and stage. Storm samples were also captured through use of an Isco auto-sampler. Additionally, bi-weekly grab samples were taken at each site. …

Motion Control For A Tracking Fluoroscope System, Gabriel Rinaldo Preliasco

Masters Theses

The tracking fluoroscope system (TFS), patent pending serial No.: 60/606,480; is a vehicle carrying a fluoroscope to take x-rays movies of person’s joints. Fluoroscope, composed by a radiation source and image intensifier, is moved by a total of four servomotors following a subject’s joint. At the same time, vehicle has to follow the subject using two driving-steering servomotor wheels. This thesis is the result of internal research developed at the Mechanical Aerospace Biomedical Engineering Department at the University of Tennessee.

The thesis objective is to determine the best control system for TFS subject tracking function in linear translational mode. Kinematic …

A Performance Analysis Of The Cmaq Model And Its Sensitivity To Ozone Precursors In East Tennessee, Karthikeyan Ramaswamy

Masters Theses

This paper presents the results of sensitivity analyses and its effect on ozone concentrations in East Tennessee. The objective of this research was to conduct a sensitivity analysis on ozone precursor emissions. In this research, the Models- 3/Community Multiscale Air Quality (CMAQ) and Sparse Matrix Operator Kernel Emissions (SMOKE) models were utilized to predict base case ozone concentrations based on 1999 National Emission Inventory (NEI) in East Tennessee from August 27th to September 9th, 1999. The modeling domain consisted of a three tiered nested domain with grid resolutions of 36 km, 12 km and 4km. The 4 km domain covered …

Developing An Information System To Integrate A Manufacturing Firm And Its Supplier Base, Abhishek Padiyar

Masters Theses

A manufacturing firm is encouraging their suppliers to achieve the goal of zero-defects. However, due to the high expectations set by the manufacturing firm, the suppliers are finding it quite challenging to be able to immediately react to the quality requirements of the manufacturing firm. The manufacturing firm wants to ensure that the suppliers take the necessary actions to eliminate the reoccurrence of specific non-conformities. This thesis illustrates the application of an information system that integrates the manufacturing firm with their supplier base. The information system is developed based on the framework of Failure Modes and Effects Analysis (FMEA). It …

Fracture Toughness: Evaluation Of Testing Procedure To Simplify Jic Calculations, Brandon Paul Pehrson

Masters Theses

The purpose of this study is to examine the current fracture toughness test procedure and to determine if there is an easier, less complicated method to get the J_Ic value from a test record for fracture toughness specimens. The current method for constructing J_Ic is complicated and involves a detailed computer program or spreadsheet. The objective in this study is to simplify the analysis for the determination of J_Q.

This study has shown that the load and displacement record for a fracture toughness specimen can be used to directly estimate a J_Q value, a provisional …

Modeling And Analysis Of Active Front-End Induction Motor Drive For Reactive Power Compensation, Pankaj Prabhakar Pandit

Masters Theses

In this thesis, an active front end induction motor drive for reactive power compensation is analyzed. The classical vector control approach for high performance control of an induction motor drive is a well established industry standard today. The same idea of decoupled control is extended to the line-side PWM converter for achieving better dynamic performance.

The system model is obtained using d-q rotating frame theory. The i_qe component of line currents is used to control the reactive power. The i_decomponent is used to control the dc-link voltage and also to supply active power required by the motor. …

Synthesis And Analysis Of Anionic Hydrogel Scaffolds For Endothelial Cell Tissue Engineering, Abitha Sundararajan

Masters Theses

Acidic hydrogels are cross-linked polymer networks that contain neutral and negatively charged monomers. The degree of negative charge on these soft materials plays a critical role in their biomedical applications. In particular, their use as a scaffold for cardiovascular applications depends on their charged and swollen states. The amount of negative charge, however, is a complicated function of the fabrication conditions, monomeric dissociation constants, ionic strengths and pH of the surround bath solution. This study, therefore, considered four representative acidic hydrogels and their physical properties and interactions with endothelial cells. The acidic monomers methacrylic acid (MAAc) and sulfoethylmethacrylate (SEMA) were …

An Evaluation Of Alternative Permissive Periods On Non-Coordinated Phase Performance In Coordinated Traffic Signal Systems, Manoel Mendonca De Castro-Neto

Masters Theses

Currently, there are some concerns regarding coordinated-actuated traffic signal operations. First of all, there is no consistent nomenclature to describe coordination modes. Different traffic signal controller manufacturers use different terminologies and their terms are not necessarily meaningful or intuitive. Actually, one can find inconsistency in the terminology used even by a specific manufacturer just by trying to understand (or decipher) the manual. Secondly, and this might be just a consequence of the first concern, it seems that many traffic engineers and technicians are not aware of the particularities and differences among the coordination modes.

The main purpose of this study …

Joint Unmanned Combat Air System Matching Mission Requirements, Performance Capabilities, And Critical Aviation Systems, Kevin M. Claffy

Masters Theses

The Joint Unmanned Combat Air Systems (J-UCAS) acquisition program is a joint Air Force and Navy effort led by the Defense Advanced Research Projects Agency (DARPA) to demonstrate a networked system of unmanned combat air vehicles (UCAV) to effectively and affordably prosecute 21st century combat missions. The potential of these weapon systems to perform dangerous combat missions at a relatively low-cost and low-risk has garnered significant interest from both Congress and the Department of Defense (DoD) and raised expectations that the J-UCAS will replace some of the DoD’s aging tactical aircraft fleet. This paper will address the requirement for the …

Modeling And Simulation Of A Trailer With Band Track Over Wheels, Hemmant Gopal

Masters Theses

No abstract provided.

Ridge Regression Approach To Color Constancy, Vivek Agarwal

Masters Theses

This thesis presents the work on color constancy and its application in the field of computer vision. Color constancy is a phenomena of representing (visualizing) the reflectance properties of the scene independent of the illumination spectrum. The motivation behind this work is two folds:
The primary motivation is to seek ‘consistency and stability’ in color reproduction and algorithm performance respectively because color is used as one of the important features in many computer vision applications; therefore consistency of the color features is essential for high application success. Second motivation is to reduce ‘computational complexity’ without sacrificing the primary motivation.
This …

Cure-Induced Stress Control In Thermosetting Polymer Composites, Richard W. Burgess

Masters Theses

During the cure of polymer matrix composites, induced stresses develop due to shrinkage of the matrix material. Consequences of this can lead to shifting of the reinforcement, adversely affecting final properties of the material, or the induced stresses can alter the final geometry of the part. With the use of a new closed loop feedback program developed, residual stresses built up during cure were minimized. Experiments were performed using the EPON 828 resin with two types of reinforcement, carbon and glass fiber. The residual stress built up during the optimized cure cycle was compared with that produced during the lPanufacturer …

Modeling Of Unreinforced Construction Joints In Plain Concrete Using Gt Strudl, James Christopher Carroll

Masters Theses

The purpose of this study was to develop a method to predict the behavior of unreinforced concrete construction joints using the computer program GT STRUDL. Two three-dimensional finite element models of a navigation lock wall were constructed. The wall was subjected to eccentric prestress forces, which brought about concern for lift-off within the lock wall.

Eleven loading combinations were evaluated, which were created from seven independent loading conditions. Stresses for each loading combination were compared to nominal strength values as detennined by ACI 318-02, Chapter 22, for plain concrete. Results show the stresses to be acceptable throughout the wall and …

Analytical And Experimental Modal Analysis Of A Micro Cantilever Beam, Aaron Lee Echols

Masters Theses

Micro cantilever beams are used extensively in experimental nanomechanics. They were initially used as an integral component in atomic force microscopes (AFM) to map surfaces or objects with micro, nano, or even atomic precision. Recently, micro cantilever sensors are being studied for possible use in determining bio/chemical agents under a variety of military and homeland security conditions. The key here is to identify the absorbed agent in terms of cantilever deflections, whether static or dynamic. Micro cantilevers are also being studied for possible use in micro/nano engines. In this case, micro particles impact micro cantilevers as a result of Brownian …

An Analysis Of Target Location Error Generated By The Litening Pod As Integrated On The Av-8b Harrier Ii, Shaun C. Spang

Masters Theses

The modern battlefield continues to rapidly change requiring a quick, reactive, and precise strike capability by air forces. The Litening Pod (Tpod), as integrated on the AV-8B Harrier, can now be easily used by the pilot as a target coordinate generation source for global positioning system (GPS) guided weapons. This thesis has attempted to mathematically determine the target coordinate generation accuracy of the Tpod. The total mathematical target location error (TLE) was then compared to actual flight test data.

The analytical approach to calculating the accuracy of Tpod generated target coordinates has shown to be too conservative. This is due …

The Evaluation Of The Low Probability Of Intercept Altimeter (Lpia) And Its Impact On Ea-6b Operations, Daniel Philip Covelli

Masters Theses

The purpose of this study was to evaluate the performance of the Low Probability of Intercept Altimeter (LPIA) Radar Altimeter (RADALT), which was selected to replace the AN/APN-194 RADALT, as installed in the EA-6B Prowler and conclude how the new system will impact the tactical operation of the EA-6B aircraft if allowed to proceed to and pass the operational phase of testing in its current status.

The LPIA was selected to replace the APN-194 as part of the overall EA-6B aircraft Block III test program in order to comply with the Chief of Naval Operations’ (CNO’s) mandate to install the …

The Inverse Application Of Conformal Mapping Techniques To Describe Groundwater Flow-Regimes Through A Window In The Upper Claiborne Confining Layer, Patrick Lasater Mcmahon

Masters Theses

The purpose of this study was to establish an inverse algorithm to solve the analytic element groundwater modeling equations, developed by Anderson (2001), for state parameters based on head data from an appropriate field site. The analytical element model (AEM) equations developed by Anderson (2001) are a complex variable technique to describe flow regimes through a gap in a confining layer that otherwise separates two confined aquifers. Anderson’s equations are based on the assumptions that hydraulic conductivity is constant in the respective confined aquifers. It also assumes a hydraulic conductivity of zero for the confining layers in the system.

A …

Fundamental Studies Of Stabilization Of Polyacrylonitrile Precursor, Stephen Alan White

Masters Theses

The purpose of this study was to examine the stabilization of polyacrylonitrile precursor. Currently, the stabilization of polyacrylonitrile is the limiting step in the production of carbon fibers because of its cost and time requirements. By furthering the understanding of the stabilization process, it may be possible to reduce the cost and time required, allowing the widespread use of carbon fiber in several industries to be achieved.

In this study, the effects of temperature, time, environment, and pressure on the stabilization of polyacrylonitrile were examined. Once fiber samples were heat treated, four experimental techniques were used to examine the samples. …

Time-Varying Autoregressive Modeling Of Nonstationary Signals, Xiaolin Luo

Masters Theses

Nonstationary signal modeling is a research topic of practical interest. In this thesis, we adopt a time-varying (TV) autoregressive (AR) model using the basis function (BF) parameter estimation method for nonstationary process identification and instantaneous frequency (IF) estimation. The current TVAR model in direct form (DF) with the blockwise least-squares and recursive weighted-least-squares BF methods perform equivalently well in signal modeling, but the large estimation error may cause temporary instabilities of the estimated model.

To achieve convenient model stability monitoring and pole tracking, the TVAR model in cascade form (CF) was proposed through the parameterization in terms of TV poles …

An Investigation Of The Current Distribution In An Hts Triaxial Power Cable And Its Operational Impacts On A Power System, Marcus Aaron Young Ii

Masters Theses

An investigation of the current distribution in a 3-phase triaxial superconducting cable was conducted to study the phase imbalance under steady-state operation and to assist in the construction of a transient model to study operational impacts in a power grid.

The triaxial cable consisted of three superconducting concentric phases inside a copper shield, with each phase composed of multiple layers of BSCCO tape wound helically in opposite directions. Current distribution within the cable was determined by using an electric circuit (EC) model containing the self and mutual inductances resulting from both axial and tangential magnetic fields. An AC loss term …

Traffic Signal Phase Truncation In The Event Of Traffic Flow Restriction, Scott Glenn Beaird

Masters Theses

This thesis presents a proposed improvement to traffic signal controller logic. The concept consists of truncating a phase on which there is demand but zero or minimal flow due to a restriction of traffic. The logic presented in this thesis recognizes such a flow restriction and, consequently, terminates the phase in favor of a conflicting call for service. The theory of the concept is addressed and methods of implementation are explored.

An experimental analysis was conducted in order to qualify the benefit of the phase truncation concept. This analysis was conducted using the VISSIM simulation software in conjunction with a …