Engineering Commons^™

A New Approach To Optimization Of Dynamic Reactive Power Sources Addressing Fidvr Issues, Weihong Huang

Masters Theses

Dynamic reactive power (var) sources, e.g. SVCs and STATCOMs, can effectively mitigate fault-induced delayed voltage recovery (FIDVR) issues or even voltage collapse. However, their optimal allocation in a power grid is a complicated nonlinear optimization problem since the post-fault voltage trajectories have to be solved to check constraints on voltage responses. Thus, solvers of both nonlinear optimization and power system differential and algebraic equations (DAEs) are required.

Currently, most of existing methods merely achieve dynamic optimization locally with great dependence on the initial operation point. Also, complicated algorithm and time consuming are obstacles for the practical implementation.

This thesis proposes …

A Sensor For Oxygen In A Potassium-Sodium Alloy, Michael George Pastis

Masters Theses

This project supports a research project to determine the configuration for heat exchanger welds in a space reactor. The reactor is a sodium-potassium (NaK) cooled reactor for use on future missions on the lunar surface or on Mars. Various types of welds in Type 316L stainless steel have been positioned in a furnace which is part of a NaK test loop. The specimens are bathed in circulating NaK at 600 degrees centigrade.

Since the oxygen concentration in the NaK is a major factor in corrosion of the weld specimens, it must be carefully monitored and controlled. However, few techniques are …

A Low-Power Approach For Front End Biological Signal Conditioning, Logan Smith Taylor

Masters Theses

In a lab-on-a-chip (LOC) application, the measurement of small analog signals such as local temperature variation often involves detection of very low-level signals in a noisy micro-scale environment. This is true for other biomedical monitoring systems as well. These systems observe various physiological parameters or electrochemical reactions that need to be tracked electrically. For temperature measurement pyroelectric transducers represent an efficient solution in terms of speed, sensitivity, and scale of integration, especially when prompt and accurate temperature monitoring is desired.

The ability to perform laboratory operations on a small scale using miniaturized LOC devices is a promising biosensing technique. The …

On The Development Of Conductive Textile Antennas, Dounia Baiya

Masters Theses

UWB systems are becoming increasingly utilized due to their use in a variety of applications. Meanwhile, many advances have been achieved in the realm of conductive textiles. These textiles can be used as a sensing system or implemented wearable antennas. Combining these two applications is attractive for a number of reasons. First, wearable antennas constructed entirely from fabric offer a cost- effective, flexible solution when compared to rigid antennas. Second UWB technology is also attractive for body area network applications due to the low power operation and the inherent low radiated power in its system design.

In our implementation accurately …

Zone Refining Of Raw Materials For Metal Halide Scintillator Crystal Growth, Thomas Williams Mcalexander

Masters Theses

In recent years, scintillators have been researched for homeland security applications where properties such as high light output and low energy resolution are required for efficient gamma ray spectroscopy. Several promising scintillators, including SrI₂ [Strontium Iodide], CsSrI₃ [Cesium Strontium Iodide]_, and KSr₂I₅ [Potassium Strontium Iodide] are activated with EuI₂ [Europium Iodide]. The quality of EuI₂ raw material is generally poor and inconsistent as-received from the manufacturer. Material purity is known to affect its scintillation performance, and so purification processes have been investigated to improve the performance of Eu-doped [Europium-doped] scintillators. In this …

Design And Model Of The Frame For Hagrid (Hybrid Array Of Gamma Ray Detectors), Santiago Munoz

Masters Theses

Transfer reactions in inverse kinematics have provided critical information in the study of exotic nuclei. However, transfer reactions with charged particles suffer from poor resolution. The measurement of gamma-rays offers several advantages: they provide not only good resolution in measurements but also other information about the nuclei like lifetimes of unstable states. The combination of these two methods would be the ideal situation to gather information about nuclear structure.

HAGRiD, which stands for The Hybrid Array of Gamma Ray Detectors, is a LaBr3(Ce) [lanthanum bromide crystal with a cerium activator] scintillation array to measure gamma rays from transfer reactions and …

Adomian Decomposition Of The Flowfield In A Simulated Rocket Motor, Jeisson Juliany Parra

Masters Theses

The work presents an analytic, approximate solution to an internal flowfield for a solid rocket motor. The flowfield is modeled as a wall-normal injection or suction in a symmetric porous channel with laterally expanding or contracting walls. From the effective speeds that gases are ejected into the combustion chamber of typical rocket motors, the flowfield is modeled to be incompressible. Since the flame zone occurs in a very thin space above the propellant grain surface, it will be disregarded. Assuming linearly varying axial velocity and uniform expansion (or contraction), the Navier-Stokes equations will be reduced into a single nonlinear equation …

Validation Of A Modified Parallel Compressor Model For Prediction Of The Effects Of Inlet Swirl On Compressor Performance And Operability, Reggie Floyd

Masters Theses

Engine inlet distortion complications have plagued the turbine engine development community for decades, and engineers have developed countless methods to identify and combat the harmful effects of inlet distortion. One such type of distortion that has gained much attention in recent years is known as inlet swirl, which results in a significant flow angularity at the face of the engine. This flow angularity can affect the pressure rise and flow capacity of the fan or compressor, and subsequently affect compressor and engine performance.

Previous modeling and simulation efforts to predict the effect inlet swirl can have on fan and compressor …

Estimating Streambank Erosion Using Gps-Based Watershed-Scale Video Mapping And Usepa Bancs For The Development Of Sediment Tmdls, Kelsey Jo Hensley

Masters Theses

According to the United States Environmental Protection Agency (USEPA), sediment is one of the most common water pollutants in the nation’s rivers. Consequently, the identification of streambank locations with high erosion potential is important in reducing sediment input via management and monitoring practices. Furthermore, the estimation of erosion rates and sediment loads can assist in the development of Total Maximum Daily Loads (TMDLs). The objective of this study was to integrate two USEPA-recommended approaches with the Streambank Video Mapping System (SVMS) in order to predict site-specific Total Daily Sediment Loads (TDSLs) and calculate sediment TMDLs for streambank erosion over several …

Characterization Of Lithium-6 As A Commercial Helium-3 Alternative For Nuclear Safeguards And Security, Alexander Martin Okowita

Masters Theses

Helium-3 detectors are efficient, reliable neutron detectors, but their high demand has reduced their supply to a very miniscule level, making them very expensive. The goal of this project is to test and evaluate an alternative produced by industry. Current testing is being done with a Lithium Zinc Sulfide (⁶LiF:ZnS(Ag)) detector from Aspect used in their portal monitors.

There are three basic requirements for neutron detectors used in nuclear safeguards and security: 1) high absolute detection efficiency, 2) maintaining neutron detection efficiency when simultaneously exposed to a high gamma ray exposure rate, and 3) the ability to maintain …

Laboratory Investigation Of Type I And Type Ii Hardened Cement Emulsified Asphalt Mortar, Tyler E. Rutherford

Masters Theses

The research presented in this thesis investigated the mechanical and viscoelastic properties of a relatively new construction building material that has been given a lot of attention in the past decade. Cement emulsified asphalt mortar (CEAM) has unique properties that differ from concrete and asphalt binder alone as this hybrid material combines the high strength of portland cement composites and the flexibility of asphalt materials. Functioning as a damping material for ballastless high-speed rail track bed, CEAM has the potential to be utilized in other areas of construction.

The work presented in this thesis is broken down into two studies, …

Investigating Instabilities With Hec-Ras Unsteady Flow Modeling For Regulated Rivers At Low Flow Stages, Jennifer Kay Sharkey

Masters Theses

Dams are used throughout the United States for generation of electricity and flood control. The Tennessee River Valley’s regulated river system extends through Tennessee and parts of Kentucky, Mississippi, Alabama, Georgia, North Carolina, South Carolina, and Virginia. Of the dams in this area, 49 are managed by the Tennessee Valley Authority (TVA). The TVA forecasts and monitors the activities related to these dams and others in the area on an around-the-clock basis to ensure maximum generation potential is attained and to prevent flooding of the surrounding cities. To best forecast hydrology for the regulated river system, the TVA chose to …

An Autonomous Online I-V Tracer For Pv Monitoring Applications, Cameron William Riley

Masters Theses

With the unprecedented growth of photovoltaic technologies and their implementation in recent times, more precise methods of determining modules health, degradation, and performance are needed. Current monitoring efforts are helpful in determining these attributes but do not provide all of the information necessary to truly understand the health properties of the PV module in question. The current-voltage curve, or I-V curve, provides a level of insight into a PV module’s health unparalleled by most monitoring efforts. However, the tools which measure the I-V curve exist in an undesirable form—PV must be disconnected from its load and connected to the tool …

Modeling Integral Fuel Burnable Absorbers Using The Method Of Characteristics, Erik Daniel Walker

Masters Theses

Modern core designs that utilize Westinghouse fuel technology employ the use of Integral Fuel Burnable Absorbers (IFBA) that consists of very thin coatings of boron absorber material on the fuel pellets. While IFBA has proven to be an effective burnable absorber, it does present a neutronics modeling challenge. The difficulty of modeling IFBA using the Method of Characteristics (MOC) transport method is well known, and arises from the fact that IFBA is a very small, but also very important, region in nuclear fuel. Experience in modeling IFBA at the pin cell and single assembly lattice level requires a decrease in …

Analytical And Computational Modeling Of Membrane Nanotubes, Sina Mirzaeifard

Masters Theses

This thesis investigates the interplay between cell membranes and the actin cytoskeleton in cellular structures known as membrane nanotubes. Membrane nanotubes are slender membrane structures that physically connect cells over long distances, and experiments suggest that they play a role in transferring material and information between cells. Disrupting the actin cytoskeleton disrupts membrane nanotubes. Although recent studies have revealed insight into the physical properties and functions of membrane-actin systems, further research is needed to understand their behavior in biological contexts. Membrane nanotubes provide a novel system with which to investigate interactions between the cell membrane and actin.

In this thesis, …

Optimizing Boat Hull And Deck Mold Storage Scheduling With Linear Programming, Tron Bjorn Dareing

Masters Theses

With a wide range of products, Sea Ray uses a vast amount of large boat molds for each of the different boat models. Storing and transporting these molds can be an issue with introducing high variability in the production process. One of the largest problems deals with the utilization of the employees’ time with the large amount of boat production. Having the boat molds being ready for production is a critical part of the manufacturing of quality boats. There is non-value added time spent on preparing the molds for the lamination process and storing them in various areas. This problem …

Fabrication And Characterization Of Cu-Co Alloy Nanoparticles Via Pulsed Laser Dewetting, Shaofang Fu

Masters Theses

The fabrication and characterization of Cu[Copper]-Co[Cobalt] alloy nanoparticles are addressed in this thesis. First, Cu-Co alloy thin films with total thickness of ~10 nm [nanometer] were deposited on both 100 nm SiO₂ [silicon dioxide] coated silicon wafers and quartz substrates using RF magnetron sputtering system. Three structures were studied in this work: (1) ~10 nm co-sputtered Cu-Co alloy thin film. (2) ~5 nm (at center) Cu thin film covered by ~5 nm (at center) Co thin film. (3) ~5 nm (at center) Co thin film covered by ~5 nm (at center) Cu thin film. In addition, ~10 nm pure …

Joint Reaction Force And Contributions Of Surrounding Muscles To Knee Joint Load During Stair Ascent In Total Knee Replacement Patients And Healthy Individuals, Robert Jacob Rasnick

Masters Theses

Total knee replacement (TKR) is commonly used to correct end stage knee osteoarthritis (OA) of the knee joint. Unfortunately, difficulty with stair climbing has been seen to exist, prolonging the challenges of TKR patents. Complete understanding of loading at the knee is of great interest in order to aid patient populations, implant manufacturers, rehabilitation, and future research. The outcome of a TKR is intended to reestablish normal motion and loading of the knee. Musculoskeletal modeling provides a means to accurately approximate joint loading and the corresponding muscle contributions during a movement.

The purpose of the present study was to examine …

A Lean Information Management Model For Efficient Operations Of An Educational Entity At The University Of Tennessee, Harshitha Muppaneni

Masters Theses

A software based Management Information System (MIS) is designed and implemented in the Department of Industrial and Systems Engineering at University of Tennessee to handle different types of data requests that are currently processed through multiple steps. This thesis addresses the current resource intensive data management model in educational institutions and proposes a decentralized and customized solution. The proposed software based data management system provides information to authorized sources in the requested format with minimal or no time consumption. The quantification of the new systems’ impact is done by comparing it with current data management process using Graph Theoretic Approach …

Preliminary Design And Evaluation Of A Tethered Balloon System With A Constant Volume Torus Envelope For Low Altitude Operations In Light Winds, Khoy Noel Callwood

Masters Theses

This document proposes the use of a tethered aerostat system with a constant volume, torus-shaped envelope as a platform for atmospheric monitoring at low altitudes. Manufacturers can make balloons into a variety of shapes, but the most common are spherical and ellipsoidal. Tethered balloons and constant volume balloons have been in use for years but not in combination. This document serves to guide the reader through the preliminary development and evaluation of a tethered balloon system with a constant volume torus envelope. This design study concluded that a balloon system using a tethered, constant volume torus envelope is viable but …

Low Temperature Thermally Activated Cvd Of Silicon On Molybdenum For Oxidation Protection, Brian C. Jolly

Masters Theses

The United States Global Threat Reeducation Initiative (GTRI) is promoting the production of molybdenum-99 without the use of uranium-235. One possible route, called neutron capture technology, is through the activation of molybdenum-98 via irradiation. GE-Hitachi has identified a location within their boiling water reactors for molybdenum-98 irradiation, but the elevated temperatures present risk oxidizing the molybdenum. This work explored using a silicon coating to protect the molybdenum from oxidation. With silane gas as the precursor, chemical vapor deposition was employed to produce the silicon coating. Characterization was performed and showed a discrete silicon layer was deposited with little to no …

Statistical Analysis Of Disturbances In Power Transmission Systems, Liu Liu

Masters Theses

Disturbance analysis is essential to the study of the power transmission systems. Traditionally, disturbances are described as megawatt (MW) events, but the access to data is inefficient due to the slow installation and authorization process of the monitoring device. In this paper, we propose a novel approach to disturbance analysis conducted at the distribution level by exploiting the frequency recordings from Frequency Disturbance Recorders (FDRs) of the Frequency Monitoring Network (FNET/GridEye), based on the relationship between frequency change and the power loss of disturbances - linearly associated by the Frequency Response. We first analyze the real disturbance records of North …

Benefits Of Obtaining An Advanced Degree In Engineering Management, Inna Majdalani

Masters Theses

In this study, an attempt to evaluate factual benefits of an advanced degree in the field of Engineering Management has been made. The study concentrated on estimation of economic and non-monetary benefits, reported by various groups of Engineering Management alumni of The University of Tennessee. The comparison between age, gender and career variation groups was completed, and the possible reasons for these findings were discussed. Also, additional data pertaining to program cost coverage, demographics, composition of alumni pool, and appreciation of the Engineering Management program in their post-graduation careers was collected and analyzed. The study suggests that, even though there …

Digital-To-Analog Converter Interface For Computer Assisted Biologically Inspired Systems, Nicholas Conley Poore

Masters Theses

In today's integrated circuit technology, system interfaces play an important role of enabling fast, reliable data communications. A key feature of this work is the exploration and development of ultra-low power data converters. Data converters are present in some form in almost all mixed-signal systems; in particular, digital-to-analog converters present the opportunity for digitally controlled analog signal sources. Such signal sources are used in a variety of applications such as neuromorphic systems and analog signal processing. Multi-dimensional systems, such as biologically inspired neuromorphic systems, require vectors of analog signals. To use a microprocessor to control these analog systems, we must …

Hybrid Rocket Design Study Utilizing Nozzle Cooling And Aft-End Vortex Oxidizer Injection, John Nicholas Quigley

Masters Theses

The current study focused on two innovations intended to reduce the cost and enhance the performance of hybrid rockets. The majority of the emphasis was placed on the design, fabrication and testing of a 3-D printed, water cooled nozzle. This work was done as proof of concept to show that complex, high temperature components could be manufactured using these new techniques, thereby substantially bringing down fabrication costs and allowing configurations that are not feasible using traditional machining. A water-cooled calorimeter nozzle was made and used in thrust stand tests to verify analytic and numerical heating models used in the design …

A Stochastic Model For Self-Scheduling Problem, Lili Zhang

Masters Theses

The unit commitment (UC) problem is a typical application of optimization techniques in the power generation and operation. Given a planning horizon, the UC problem is to find an optimal schedule of generating units, including on/off status and production level of each generating unit at each time period, in order to minimize operational costs, subject to a series of technical constraints. Because technical constraints depend on the characteristics of energy systems, the formulations of the UC problem vary with energy systems. The self-scheduling problem is a variant of the UC problem for the power generating companies to maximize their profits …

An Evaluation Of Void Formation In Ex-Service And Creep Tested Hp Alloy Tubing Used For Hydrocarbon Reforming, Zane William Fox Palmer

Masters Theses

HP alloy tubing is commonly used in petroleum reforming facilities for its high temperature strength and resistance to corrosion. Unfortunately, the tubes can experience failure during service caused by the formation of voids in the tube wall brought on by creep stress generated by the pressure differential and thermal gradient between the inside and outside diameters of the tube. The purpose of this project was to analyze the formation of voids in eight ring sections, each from a different ex-service tube, from a total of three different manufacturers (identified as M1, M2, and M3). Further analysis of the ex-service tubes …

Chemical Flux During Event Stormwater Flows In The Great Smoky Mountains National Park: Comparison Of Two Streams Varying By Drainage Area And Elevation, Matthew Williams Aplin

Masters Theses

Streams in the Great Smoky Mountains National Park in North Carolina and Tennessee have been impacted by acid deposition from anthropogenic sources for decades. Recent declines in acid deposition throughout the eastern U.S. appear to be initiating improvements in stream water quality. However, watershed recovery could take decades due to regional differences in the hydrologic and biogeochemical processes that influence chemical fate and transport. These processes have been extensively studied at longer time scales (i.e. seasonally, annually), by long-term annual ion budgets, and study designs based on grab samples. Less known are the acidification effects on streams through rapid ion …

Design And Fabrication Of A Low-Cost Turbine Engine Component Testbed (Tect), Joshua A. Hartman

Masters Theses

With gas turbine engine testing becoming very expensive because of the increasing complexity involved with the engine, engine subsystems, and test support systems, a low-cost Turbine Engine Component Testbed (TECT) is proposed. This engine build is given the designation J1-H-02. In the present study, a small augmented gas turbine engine (GTE) is constructed. The TECT engine is built with modularity as a key design consideration to allow for flame-tube patterns and augmentor sections to be changed quickly for combustion experiments that have gained impetus due to combustion anomalies/instabilities inherent with future military engine augmentors. This testbed allows for an effective …

Thick Target Yield Of Th-229 Via Low Energy Proton Bombardment Of Th-232, Justin Reed Griswold

Masters Theses

Actinium-225 is one of the more effective radioisotopes used in alpha radioimmunotherapy. Due to its ten-day half-life, it is more efficient to create its precursor, ²²⁹Th [Thorium-229] (t_1/2[half-life] = 7932 ± 55 years). In this work, ²²⁹Th was produced via 40 MeV [Mega electron Volts] proton bombardment of a thick ²³²Th [Thorium-232] target. The irradiation took place at the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Lab (ORNL). The target, consisting of 23 stacked natural thorium foils (137 mg/cm² [milligrams per square centimeter] each), was irradiated with 50 nA [nanoamps] of …