Engineering Commons^™

Developing Leading And Lagging Indicators To Enhance Equipment Reliability In A Lean System, Dhanush Agara Mallesh

Masters Theses

With increasing complexity in equipment, the failure rates are becoming a critical metric due to the unplanned maintenance in a production environment. Unplanned maintenance in manufacturing process is created issues with downtimes and decreasing the reliability of equipment. Failures in equipment have resulted in the loss of revenue to organizations encouraging maintenance practitioners to analyze ways to change unplanned to planned maintenance. Efficient failure prediction models are being developed to learn about the failures in advance. With this information, failures predicted can reduce the downtimes in the system and improve the throughput.

The goal of this thesis is to predict …

Analysis Of Nfirs Data For Sensitivity To Foreclosure And Other Select Features, Alexander Meadows Asbury

Masters Theses

Arson is a grave threat to life and property. In the United States, fire information is collected and disseminated through the National Fire Incident Reporting System (NFIRS). Fire records obtained from NFIRS contain a full range of available information. This information includes the initial incident details in addition to investigative information regarding the cause of ignition and factors contributing to ignition. Combating the arson problem is accomplished in large part by understanding the motives and opportunities of those who commit arson. A common motive for arson is financial gain through insurance fraud. By connecting NFIRS data with mortgage and foreclosure …

Modeling Of Dislocation Channel Formation And Evolution In Irradiated Metals, Peter James Doyle

Masters Theses

Defect-free dislocation channel formation has been reported to promote plastic instability during tensile testing via localized plastic flow, leading to a distinct loss of ductility and strain hardening in many low-temperature irradiated materials. In order to study the underlying mechanisms governing dislocation channel width and formation, the channel formation process is modeled via a simple stochastic dislocation-jog process dependent upon grain size, defect cluster density, and defect size. Dislocations traverse a field of defect clusters and jog stochastically upon defect interaction, forming channels of low defect-density. Based upon prior molecular dynamics (MD) simulations and in-situ experimental transmission electron microscopy (TEM) …

Automated Program Profiling And Analysis For Managing Heterogeneous Memory Systems, Adam Palmer Howard

Masters Theses

Many promising memory technologies, such as non-volatile, storage-class memories and high-bandwidth, on-chip RAMs, are beginning to emerge. Since each of these new technologies present tradeoffs distinct from conventional DRAMs, next-generation systems are likely to include multiple tiers of memory storage, each with their own type of devices. To efficiently utilize the available hardware, such systems will need to alter their data management strategies to consider the performance and capabilities provided by each tier.

This work explores a variety of cross-layer strategies for managing application data in heterogeneous memory systems. We propose different program profiling-based techniques to automatically partition program allocation …

Developing A Platform For Integrating Disability Issues Into City Municipality Decisions; Case Study: City Of Knoxville, Sravanthi Pamu

Masters Theses

The People with Disabilities (PWD) & Senior Citizen (SC) are isolated from the mainstream society, and they face several barriers in everyday life. There is no communication platform for them to express their concerns, in turn, participate in the city municipality policy decisions related to PWD- & SC-friendly city development. The purpose of this research is to integrate disability and senior citizen issues in the city of Knoxville to the city council decisions. The comprehensive literature search is done to identify the frequently mentioned disability and age-friendly city factors. An effective survey was designed to identify the issues in collaboration …

An Analog Cmos Particle Filter, Trevor Watson

Masters Theses

Particle filters are used in a variety of image processing and machine learning applications. Their main use in these applications is to gather information about a system of objects, by using partial or noisy observations collected from sensors. These observations are used to associate points of interest in the observations with objects and maintain this association through a series of observations.

In this paper I will investigate the performance of a particle filter implemented in 130nm analog CMOS hardware. The design goal of the particle filter is low-microwatt power consumption. Using analog hardware, rather than digital ASICs or CPUs I …

Impacts Of The Heterogeneity In Consumer Valuation Of Fuel Economy On Corporate Average Fuel Economy Standards Compliance, Nawei Liu

Masters Theses

This study investigated potential impacts of the heterogeneity in consumer valuation of fuel economy on the compliance with fuel economy standards with two analytical approaches. One approach is to provide theoretical analysis of the heterogeneity impacts on the market acceptance of high-efficiency vehicles. The other approach utilizes a consumer choice based simulation method to analyze the heterogeneity impacts on the compliance with the Corporate Average Fuel Economy (CAFE) Standards for the entire light duty vehicle fleet in the U.S. Our findings suggest two possible conditions which are defined based on relative acceptance of high-efficiency vehicles in the market, and they …

Positron Emission Particle Tracking Software Maturation Project, Eric Michael Moore

Masters Theses

Positron Emission Particle Tracking (PEPT) software at the University of Tennessee (MultiPEPT) has demonstrated promising performance in multiple measurement domains. In order to contribute to its further development, a full codebase audit and three focused performance assessments were undertaken. Several improvements were made to the codebase as a result of the audit. The assessments demonstrated a linear axial detector- MultiPEPT response, the effect of mesh size variation, and the effect of temporal overlap variation. A number of best practices are compiled for effective use of MultiPEPT.

Improvements To Nestle: Cross Section Interpolation And N-Group Extension, William Matthews Kirkland

Masters Theses

The NESTLE program is a few-group neutron diffusion reactor core simulator code utilizing the nodal expansion method (NEM). This thesis presents two improvements made to NESTLE regarding cross-section interpolation and multigroup capability.

To quickly and accurately obtain cross sections from lattice physics input data, a new cross section interpolation routine was developed utilizing multidimensional radial basis function interpolation, also known as thin plate spline interpolation. Testing showed that, for existing NESTLE lattice physics input, accuracy was retained but not improved and processing time was longer. However, the new interpolation routine was shown allow much greater exibility in the case matrix …

The Development Of Cesium Calcium Bromo-Iodide Scintillator For X-Ray And Gamma Ray Detection, Matthew Starr Loyd

Masters Theses

CsCaI₃:Eu [cesium calcium iodide doped with europium] is a promising scintillator material that can be grown from the melt, but undergoes a tetragonal to orthorhombic phase transition upon cooling at 255 °C [degrees Celsius], causing twinning and cloudiness. The purpose of this work is to suppress this solid to solid phase transition in the CsCaI₃:Eu scintillator, which has a light yield of ~40000 ph/Mev and energy resolution at 662keV of ~4%, by halide replacement to form the compound CsCaBr_xI_3-x:Eu [cesium calcium bromo-iodide doped with europium]. Crystals 8 cm³ [cubic centimeters] in …

Design Considerations For Paralleling Multiple Chips In Sic Power Modules, Fei Yang

Masters Theses

With the benefits of fast switching speed, low on-resistance and high thermal conductivity, silicon carbide (SiC) devices are being implemented in converter designs with high efficiency and high power density. Consequently, SiC power modules are needed. However, some of the preestablished package designs for silicon based power modules are not suitable to manifest the advantages of SiC devices. Therefore, this thesis aims at optimizing the package design to utilize the fast switching capability of SiC devices.

First, the power loop parasitic inductance induced by the package can lead to large voltage spikes with the fast switching SiC device. It can …

Design And Evaluation Of A Sub-1-Volt Read Flash Memory In A Standard 130 Nanometer Cmos Process, David Andrew Basford

Masters Theses

Nonvolatile memory design is a discipline that employs digital and analog circuit design techniques and requires knowledge of semiconductor physics and quantum mechanics. Methods for programming and erasing memory are discussed here, and simulation models are provided for Impact Hot Electron Injection (IHEI), Fowler-Nordheim (FN) tunneling, and direct tunneling. Extensive testing of analog memory cells was used to derive a set of equations that describe the oating-gate characteristics. Measurements of charge retention also revealed several leakage mechanisms, and methods for mitigating leakage are presented.

Fabrication of ash memory in a standard CMOS process presents significant design challenges. The absence of …

Development Of A Multi-Jointed Wing Surface Mover, Collin Arthur Strassburger

Masters Theses

The field of ornithopter research has reached a point where it has become commonplace for Computational Fluid Dynamics (CFD) solvers to have built-in capabilities for rigid solid body motion. This is suitable for micro air vehicles (MAVs) yet is often not exible enough to model wings with dynamic internal structure, such as the wings of birds and bats. There is currently no program available to perform the surface motion of a wing which has multiple independently moving joints. The code, detailed in this paper, provides the user with this type of capability. The bone lengths, joint angle properties, and thickening …

Using Naturalistic Data For Bicycle Safety Analysis: An Application Of Cyclephilly Data To Assess Wrong-Way Riding, Nirbesh Dhakal

Masters Theses

This study focuses on wrong-way riding and associated route-choice determinants of wrong-way riding. I present this application as a case study of the many types of analysis that are possible with emerging naturalistic datasets that are not limited to conventional methods (e.g., vehicle counters). I used a dataset generated from a smartphone application, CyclePhilly, that measures rider location second-by-second in Philadelphia. The dataset covers 12,202 trips by 300 unique CyclePhilly users collected from May 2014 through April 2016. The data also includes information on socio-economics of the rider, as well as cycling experience. I merged this dataset with complementary network …

Tiled Danna: Dynamic Adaptive Neural Network Array Scaled Across Multiple Chips, Patricia Jean Eckhart

Masters Theses

Tiled Dynamic Adaptive Neural Network Array(Tiled DANNA) is a recurrent spiking neural network structure composed of programmable biologically inspired neurons and synapses that scales across multiple FPGA chips. Fire events that occur on and within DANNA initiate spiking behaviors in the programmable elements allowing DANNA to hold memory through the synaptic charge propagation and neuronal charge accumulation. DANNA is a fully digital neuromorphic computing structure based on the NIDA architecture. To support initial prototyping and testing of the Tiled DANNA, multiple Xilinx Virtex 7 690Ts were leveraged. The primary goal of Tiled DANNA is to support scaling of DANNA neural …

Modeling And Design Of A Low-Level Rf Control System For The Accumulator Ring At Spallation Neutron Source, Michael G. Trout

Masters Theses

Since its commissioning in 2006, Spallation Neutron Source (SNS) at Oak Ridge National Laboratory has greatly contributed to the field of neutron science, but some critical systems are reaching end-of-life. This obsolescence must be addressed for the accelerator to continue providing world-class research capabilities. One such system needing redesign is the low-level RF (LLRF) control system for the proton accumulator ring. While this system has performed acceptably for over a decade, it is sparsely documented and robust operational models are unavailable. To ensure the new design meets or exceeds current performance metrics, we analyzed the existing LLRF control system and …

Fracture Behavior Of Single Mason Sand Particles Under Uniaxial Compression, Thuy Thanh Trieu

Masters Theses

Tensile strength of granular materials under one-dimensional (1D) compression is often examined because granular materials fracture in many applications where the soil mass experience high compression stresses. Through methods such as 1D compression, three-dimensional (3-D) imaging, and discrete element modeling, researchers had determined that the Weibull distribution is a good model to represent the tensile strengths of granular material and the fracturing strength of granular materials is dependent on mineralogy, morphology, grain-size, loading rate, gradation, coordination number, and moisture content. Uniaxial compression experiments were performed on Mason sand particles retained between US sieve #10 (2 mm) and #20 (0.84 mm) …

Dewetting Properties Of Ag-Ni Alloy Thin Films, Benjamin Scott Wolf

Masters Theses

In this study, pulsed laser induced dewetting of both patterned and continuous Nickel (Ni)-Silver(Ag) thin films was investigated extensively as a novel way to perform directed assembly of nano-particles. First, continuous Ni-Ag thin film dewetting was studied on both bulk and TEM (Transmission electron microscope) membrane substrates at a variety of compositions to better understand the dewetting dynamics of the Ni-Ag system. Then, patterned Ni-Ag thin film dewetting was studied on both bulk and TEM membrane substrates to understand how different patterns and thin film configurations effect nano-particle distribution and formation. All of this work was done in anticipation of …

Simulating Microbial Electrolysis For Renewable Hydrogen Production Integrated With Separation In Biorefinery, Christian James Wilson

Masters Theses

Biomass conversion to hydrocarbon fuels requires significant amounts of hydrogen. Fossil resources typically supply hydrogen via steam reforming. A new technology called microbial electrolysis cells (MECs) has emerged which can generate hydrogen from organic sources and biomass. The thermochemical route to fuels via pyrolysis generates bio-oil aqueous phase (BOAP) which can be used to make hydrogen. A process engineering and economic analysis of this technology was conducted for application in biorefineries of the future. Steam methane reforming, bio-oil separation and microbial electrolysis unit operations were simulated in Aspen Plus to derive the mass and energy balance for conversion of biomass. …

Design Of A Robotic Instrument Manipulator For Endoscopic Deployment, Ryan Ponten

Masters Theses

This thesis describes the initial design process for an application of continuum robotics to endoscopic surgical procedures, specifically dissection of the colon. We first introduce the long-term vision for a benchtop dual-instrument endoscopic system with intuitive haptic controllers and then narrow our focus to the design and testing of the instrument manipulator itself, which must be actuated through the long, winding channel of a standard colonoscope.

Based on design requirements for a target procedure, we analyze simulations of two types of continuum robots using recently established kinematic and mechanic modeling approaches: the concentric-tube robot (CTR) and the concentric agonist-antagonist robot …

In Service Performance Evaluation Of Erosion Prevention Sediment Control Devices, Ali Riza Hangul

Masters Theses

The Erosion Prevention and Sediment Control (EPSC) market continuously expands with the addition of new products based on research and development. While some products may require special equipment for installation, others are installation ready. There have not been any investigations conducted on installation complications and cost to gain feedback from construction field personnel with regard to which practices are performing better and/or are preferred. The objective of this thesis is to further evaluate the current practices from performance and cost perspectives, in order to improve the plans development efficiency for the Tennessee Department of Transportation’ Roadway Design, Environmental, and Operations …

High-Current Integrated Battery Chargers For Mobile Applications, Gabriel Alejo Gabian

Masters Theses

Battery charging circuits for mobile applications, such as smart phones and tablets, require both small area and low losses. In addition, to reduce the charging time, high current is needed through the converter. In this work, exploration of the Buck, the 3-Level Buck and the Hybrid Buck converter is performed over the input voltage, the total FET area and the load current. An analytical loss model for each topology is constructed and constrated by experimental results. In addition, packaging and bond wire impact on on-chip losses is analyzed by 3D modeling. Finally, a comparison between the topologies is presented determining …

Design Of An Integrated Silicon Carbide Nonlinear-Carrier Pwm Controller For Boost Converter Applications, Richard Kyle Harris

Masters Theses

Power electronics consisting of a switch mode power supply with feedback control have a great number of applications, including many that require extreme environment capability, such as the aerospace and automotive industries.

Silicon carbide (SiC) is a common material in which power devices are created for use in switch mode power supplies, such as boost converters, giving those power supplies extremely high temperature capabilities. To truly realize the temperature capabilities of SiC in power supplies, an integrated SiC converter has been designed that is also high-temperature capable.

Herein, the properties of SiC integrate circuit (IC) processes are discussed and nonlinear-carrier …

Enhancing License Plate Matching Algorithm: A New Evaluation Measurement And Threshold Determination, Brandon Cole Whetsel

Masters Theses

The process of license plate matching has continued to improve over the last decade, moving from manually intensive to automated. The text-mining technique of edit distance has been crucial to this improvement. Edit distance is not without limitations, such as determining a threshold, intuitiveness of the measurement, and character length issues.

This paper proposes an alternative evaluation method for determining plate matches. The method utilizes conditional probability rules to calculate the likelihood that two plates are a match. The alternative method is not a replacement for the traditional edit distance calculation, but rather an additional tool for practitioners. Depending on …

Two Multi-Objective Stochastic Models For Project Team Formation Under Uncertainty In Time Requirements, Fahimeh Rahmanniyay

Masters Theses

Team formation is one of the key stages in project management. The cost associated with the individuals who form a team and the quality of the tasks completed by the team are two of the main concerns in team formation problems. In this study, two mathematical models to optimize simultaneously cost and quality in a team formation problem are developed. Because team formation problem arises in uncertain environment, different scenarios are defined for the time requirement of the project. Two-stage stochastic programming and multi-stage stochastic programming are applied to solve the first and the second model respectively. The presented models …

Scalable High-Speed Communications For Neuromorphic Systems, Aaron Reed Young

Masters Theses

Field-programmable gate arrays (FPGA), application-specific integrated circuits (ASIC), and other chip/multi-chip level implementations can be used to implement Dynamic Adaptive Neural Network Arrays (DANNA). In some applications, DANNA interfaces with a traditional computing system to provide neural network configuration information, provide network input, process network outputs, and monitor the state of the network. The present host-to-DANNA network communication setup uses a Cypress USB 3.0 peripheral controller (FX3) to enable host-to-array communication over USB 3.0. This communications setup has to run commands in batches and does not have enough bandwidth to meet the maximum throughput requirements of the DANNA device, resulting …

Battery Energy Storage Emulation For Power System Applications, Jessica Danielle Boles

Masters Theses

The concept of energy storage for power systems has received increasingly more attention in recent decades, and the growing penetration of renewable energy sources has only escalated demand for it. Energy storage systems are excellent for balancing generation and load, for suppressing power fluctuations, and for providing other ancillary services to the grid. The Hardware Testbed (HTB) is a novel converter-based grid emulator created for studying the needs associated with high renewable penetration, but the system currently lacks a battery storage emulator. Thus, this work documents the development of a battery energy storage system (BESS) emulator for the HTB.

The …

Effects Of Distance, Antenna, And Channel On An Ultra Wide Band Location System, And Quantifying Them To Increase Accuracy, Nicholas Alexander Cavopol

Masters Theses

Localization has been evolving rapidly over the last 20 years, especially in the wireless world. From the advent of GPS, as well as the personal smart phone, localization has become accessible to most of the developed world. From the ability to find ones’ smartphone using a computer, to being able to locate ones’ keys using radio frequencies, there are many ways that localization has entered our lives in the last few years, however most of these either do not have high accuracy, or are only accurate in an outside environment. For indoor tracking, new technologies have been developed to help …

Impact Of Transportation Infrastructure On Stream Water Quality: Contribution From Stormwater Runoff, Andrew James Steinman

Masters Theses

Stormwater runoff is a vital concern to the health of natural waterbodies and ecosystems within urban watersheds. While there is already ample research dedicated to understanding water quality from urban roadways, few of those studies have focused on measuring the dynamics of how stream water quality during storm conditions changes due to increased pollutant load from major urban roadways. With the goal to develop effective water resource management strategies for an impaired tributary watershed, water quality was monitored at four locations within a subwatershed to determine what impact pavement runoff of a major interstate has on the impaired receiving stream. …

Leading Safety Indicators In The Construction Industry: The Case Of Tennessee, Noor Suheil Akroush

Masters Theses

The construction industry has historically suffered from high frequency and severity of accidents, making safety a major concern for all associated stakeholders. To improve safety performance, leading safety indicators have emerged as a more effective alternative to the traditional lagging indicators measured after the occurrence of an incident or accident. These are ex ante assessment of construction behaviors and processes to proactively predict safety breaches.

Prior research has defined and assessed leading safety indicators, but has not yet sufficiently understood their actual current application either at the local and/or regional levels. To this end, this research aims to study, define, …