Digital Commons Network^™

Validation Of Weak Form Thermal Analysis Algorithms Supporting Thermal Signature Generation, Elton Lewis Freeman

Masters Theses

Extremization of a weak form for the continuum energy conservation principle differential equation naturally implements fluid convection and radiation as flux Robin boundary conditions associated with unsteady heat transfer. Combining a spatial semi-discretization via finite element trial space basis functions with time-accurate integration generates a totally node-based algebraic statement for computing. Closure for gray body radiation is a newly derived node-based radiosity formulation generating piecewise discontinuous solutions, while that for natural-forced-mixed convection heat transfer is extracted from the literature. Algorithm performance, mathematically predicted by asymptotic convergence theory, is subsequently validated with data obtained in 24 hour diurnal field experiments for …

Synthesis Of Palladium-Based Electrocatalysis—From Pure Metal To Bimetallic Nanoparticles, Haijun Gao

Masters Theses

This thesis focuses on synthesis and characterization of palladium-based nanoparticles. Background information of the research in this thesis is provided in Chapter 1. Preparation and characterization of pure palladium nanoparticles are presented in Chapter 2. A fast and convenient method to prepare ultra small Pd nanoparticles via Pluronic P123 reduction is discussed in detail. Impregnation method and poly method are also studied in this chapter. Chapter 3 reports the studies of these methods to prepare ultra small bimetallic (bimetallic means a mixture of two metals) palladium-based nanoparticles. Oleylamine-mediated method used Pd nanoparticles prepared via P123 reduction as precursor. Ultra small …

On The Spherical Symmetry Of Perfect-Fluid Stellar Models In General Relativity, Joshua M Brewer

Masters Theses

It is well known in Newtonian theory that static self-gravitating perfect fluids in a vacuum are necessarily spherically symmetric. The necessity of spherical symmetry of perfect-fluid static spacetimes with constant density in general relativity is shown.

Azimuthal Seismic First-Arrival Tomography As A Proxy For Hydraulically Conductive Subsurface Fracture Networks, Matthew Brooks Edmunds

Masters Theses

The Oak Ridge Field Research Center (ORFRC) was established by the Environmental Sciences Division (ESD) at the Oak Ridge National Laboratory (ORNL) in Oak Ridge, TN, in order to study the various biogeochemical processes involved in the remediation as well as natural attenuation of a large contaminant plume that is extant in the vicinity of the ORIFRC. A part of this work has been to characterize the movement of this groundwater/contaminant plume with the use of azimuthal seismic first-arrival tomography (ASFT).

Within the general area of the ORIFRC, a 0-2 m layer of generally isotropic anthropogenic fill and unconsolidated soil …

Contextualizing The Tipton-Haynes State Historic Site (40wg59): Understanding Landscape Change At An Upland South Farmstead., Daniel Whitaker Howard Brock

Masters Theses

This thesis focuses on a contextual archaeological approach to investigate the historic landscape of the Tipton-Haynes State Historic Site. Tipton-Haynes is a late eighteenth- through twentieth-century upland south farmstead located in Johnson City, TN. Home to two prominent Tennessee families and occupied until acquired by the state in the 1960s, the site has experienced many alterations to the landscape over time. The analysis presented views the landscape as material culture investigated through a multidisciplinary approach including historic research, architectural survey, geophysical survey, dendrochronology, and archaeology. To make sense of the complex nature of the Tipton-Haynes site, multiple methods were used …

Co2 Injection Into A Deep Saline Aquifer: Porosity Measurements, Numerical Modeling, And Costs Associated With Uncertainty Of Petrophysical Parameters, Michael John Gragg

Masters Theses

Anthropogenic levels of atmospheric greenhouse gases, particularly carbon dioxide (CO₂) have increased rapidly over the last several decades and coincide with rising temperatures globally. One possible solution is to capture CO₂ before it is released into the atmosphere by large point sources, such as fossil fuel power plants. Once captured, the CO₂ can be condensed and transported to a storage facility. Of the available options for storage of condensed CO₂, geologic sequestration in deep saline aquifers is considered the most viable option.

Porosity measurements were obtained for nearly 100 core samples of the Knox …

Testing A Novel Technique To Improve Aluminum-26 Accelerator Mass Spectrometry Measurements For Earth Science Applications, Meghan Sarah Janzen

Masters Theses

The measurement of cosmogenic ²⁶Al [aluminum-26] in geological samples by accelerator mass spectrometry (AMS) is typically conducted on Al₂O₃ [aluminum oxide] targets. However, Al₂O₃ is not an ideal source material because it does not form a prolific beam of Al^- [negative atomic aluminum ions] required for measuring low-levels of ²⁶Al. This thesis presents the performance of AlN [aluminum nitride], AlF₃ [aluminum fluoride] and mixed AlN + Al₂O₃ as novel alternative source materials for the analysis of ²⁶Al. A negative ion cesium sputtering source at the Holifield …

Synthesis, Characterization, And Functionalization Of 2-Vinyl-4,4-Dimethylazlactone Brushes To Create Bio-Inspired Materials, Camille Marie Kite

Masters Theses

Functional materials built from polymer scaffolds inspire many potential uses, including as biomaterial surfaces or sensors. In situ functionalization using well-defined polymer “brushes” made by tethering polymer chains to a surface by one of their ends is explored. Specifically, poly(2-vinyl-4,4-dimethylazlactone) (PVDMA) chains, which contain a reactive azlactone ring at each repeat unit, are tethered to a surface to create brushes and these films are functionalized using a variety of small molecules, primarily amines or peptides. Relationships between polymer brush thickness, size of the functionalizing molecule, solution concentration, reaction time, and extent of functionalization were determined through measurements of brush thickness …

Effects Of Prescribed Fire And Habitat On Golden-Winged Warbler (Vermivora Chrysoptera) Abundance And Nest Survival In The Cumberland Mountains Of Tennessee, Katie Lee Percy

Masters Theses

Golden-winged Warbler (Vermivora chrysoptera) populations in Appalachia have declined precipitously over the past 45 years. The primary objective of my study was to monitor the response of Golden-winged Warblers to prescribed fire treatments on reclaimed coal mines in the North Cumberland Wildlife Management Area, Tennessee. Presence-absence surveys were conducted on eight mountain-top study sites and nest searching/monitoring was conducted on two additional sites, 2009-2011. I expanded on previous research of Golden-winged Warbler territory and nest-site selection by determining differences within main effects between used and unused territory plots, as well as used and unused nest-sites. Of my two …

Evaluation Of Tagging Techniques Gamma-Decay Probabilities Using The Surrogate Method, Timothy Lee Reed

Masters Theses

A detailed analysis of the statistical and discrete [gamma]-decay tagging techniques was conducted using the absolute surrogate and surrogate ratio method (SRM) to obtain the 92Mo(n,[gamma]) cross section in an equivalent neutron energy range of 80 to 880 keV. Excited 93Mo and 95Mo nuclei were populated using (d,p) reactions on 92Mo and 94Mo targets, respectively. The absolute surrogate 92Mo(n,[gamma]) cross sections disagreed with evaluated neutron capture cross section data by as much as a factor of 4 using the statistical tagging approach, whereas the discrete [gamma]-decay tag absolute surrogate cross section disagreed with the evaluated neutron capture cross section by …

On Decision Making: Bayesian And Stochastic Optimization Approaches, Yang Shen

Masters Theses

Decision analysis provides a framework for searching an optimal solution under uncertainties and potential risks. This thesis focuses on two problems arising in transportation engineering and computer sciences, respectively.

First, it is considered a centralized controller which imposes actions on a number of interacting subsystems. Employing an appropriate Markov Decision Process framework, we establish that the Pareto optimal solution of each subsystem will be optimal for the entire system. Synthetic data have been taken into account for verifying this claim.

Next, we focus on a supercomputing problem utilizing a hierarchical Bayesian model. We estimate an optimal solution in order to …

Power Management For Cloud-Scale Data Centers, Yanwei Zhang

Masters Theses

Recent years have seen the rapid growth of large and geographically distributed data centers deployed by Internet service operators to support various services such as cloud computing. Consequently, high electricity bills, as well as negative environmental implications (e.g., CO2 emission and global warming) come along. In this thesis, we first propose a novel electricity bill capping algorithm that not only minimizes the electricity cost, but also enforces a cost budget on the monthly bill for cloud-scale data centers that impact the power markets. Our solution first explicitly models the impacts of the power demands induced by cloud-scale data centers on …

Optimizing Maize Planting Date, Plant Population, And Fertilizer Application Rates For Lesotho Subsistence Farmers, Matthew Ryan Bruns

Masters Theses

Due to perpetually low yields, smallholder farmers throughout Southern Africa plow increasingly large plots of land in an attempt to increase their household food security. However, extensive agriculture further depresses yields because expensive inputs are spread over a larger area, provides little soil cover, and results in high soil erosion rates. To address these challenges, farmers in the Kingdom of Lesotho are beginning to adopt conservation agriculture (CA) systems. Under CA and conventional tillage systems the optimum plant population, planting date, and fertilizer rates are unknown. The effects of field preparation, planting date, weed control strategies, plant populations, and nitrogen …

Public Land In A Changing Climate: Planning For An Uncertain Future, Kathleen Marie Hauser

Masters Theses

This thesis investigates the ways in which institutions and actors consider climate change, and how the inclusion of diverse perspectives and challenges in the planning process shapes climate change governance. In particular, I asked how the participants, place-specific contexts, and decision-making processes affect environmental decision-making in Alaska’s National Parks. I discuss the literature on geographical perspectives on climate change, environmental and climate change governance, how uncertainty and risk affect decision-making in the context of climate change, and the history of land use management in the United States. This project incorporates qualitative methods to research the Climate Change Scenario Planning project …

Utility Of 1,2,4-Triazoles As Catalysts For Orr In Fuel Cells, Chinmay Nagesh Dabke

Masters Theses

The Oxygen Reduction Reaction (ORR) taking place at the cathode of a fuel cell is catalyzed by Platinum due to its high activity and good stability in the acidic polymer electrolyte membrane fuel cell (PEMFC) environment. Due to its prohibitive cost and limited reserves, it is not practical to use Pt as the catalyst for mass commercialization. By taking inspiration from nature, we have devised a series of catalysts which will help in replacing Platinum at the cathode in commercial fuel cells. To gauge the activity of various ligands, metal salts and carbon surfaces, adsorbed experiments were carried out and …

Studies Of Regolithic Vestan Samples: Brecciated Eucrites And Howardites, Sheryl A. Singerling

Masters Theses

Brecciated eucrites and howardites represent samples of the regolith of asteroid 4 Vesta. As such, they are a valuable source of data for understanding the products of surface alteration. Two different processes are investigated here: impact mixing of comminuted rocks to produce regolith samples, and formation of glasses in the regolith.

Chapter 1 describes four newly discovered eucrite breccias: three presumably paired meteorites, all named NWA 6105, and NWA 6106. For each meteorite, major- and minor-element compositions of minerals were determined using the electron microprobe. Pyroxene Fe-Mn co-variations and bulk-rock oxygen isotope compositions confirm their classification as eucrites. Variations in …

Mussel Survivorship, Growth Rate And Shell Decay Rate In The New River Basin Of Tennessee: An Experimental Approach Using Corbicula Fluminea, Grant Andrew Mincy

Masters Theses

The New River Basin (NRB) of Tennessee is home to a number of rare endemic aquatic communities. One such community of particular importance to the area, experiencing a precipitous population decline due to the fouling and pollution of their freshwater systems, is that of freshwater mussels (Bogan 2006). This study in the NRB involves measuring the mortality rates of live Asian clams (Corbicula fluminea) assemblages and the shell decay rates of their death assemblages. This study also examines the decay rates of the native Villosa iris to gather information on molluscan health and the ability of their shells …

Latin Hypercube Sampling And Partial Rank Correlation Coefficient Analysis Applied To An Optimal Control Problem, Boloye Gomero

Masters Theses

Latin Hypercube Sampling/Partial Rank Correlation Coefficient (LHS/PRCC) sensitivity analysis is an efficient tool often employed in uncertainty analysis to explore the entire parameter space of a model. Despite the usefulness of LHS/PRCC sensitivity analysis in studying the sensitivity of a model to the parameter values used in the model, no study has been done that fully integrates Latin Hypercube sampling with optimal control analysis.

In this thesis, we couple the optimal control numerical procedure to the LHS/PRCC procedure and perform a simultaneous examination of the effects of all the LHS parameter on the objective functional value. To test the effectiveness …

Characterization Of Wetting Front Geometry And Fluid Migration In The Vadose Zone Using Surface Time-Lapse Seismic First-Arrival Tomography, Rachel Elizabeth Storniolo

Masters Theses

Characterizing and quantifying vadose zone parameters and processes are critical for assessing environmental, agricultural, and engineering problems. The shallow subsurface is essential to the geologic and hydrologic cycles because it supports agriculture and ecosystems, influences water resources, and acts as a repository for contaminants. Fluid migration in the vadose zone is dependent on a number of soil characteristics (e.g. soil type and saturation). Quantifying parameters is often the primary goal of hydrological fluid-flow investigations; however, the values calculated can be misrepresentative of the subsurface due to anisotropic features. Hydraulic conductivity (K), the most common quantitative parameter used to describe fluid …

Investigating The Evolution Of Two Southern Appalachian Terrane Boundaries And A Plutonic Complex: Tectonic Implications Of Structural, Geochemical, And Geochronologic Studies In The Central Georgia Inner Piedmont, Christopher William Howard

Masters Theses

Detailed geologic mapping in the central Georgia Inner Piedmont has revealed a plutonic complex in the Cat Square terrane (CST) between the Brindle Creek and Towaliga faults ~80 km SE of Atlanta. The complex has an area ~235 km² and is composed of two distinct mappable granitoids. The High Falls Granite (HFG) is a Siluro-Devonian (424-380 Ma) porphyritic granite with characteristic blocky microcline megacrysts. The Indian Springs Granite (ISG, 313-299 Ma) has an equigranular, fine- to medium-grained texture. Some foliation in the HFG is concordant with regional trends, but a relict magmatic or secondary tectonic foliation was also observed …

Real-Time Mobile Stereo Vision, Bryan Hale Bodkin

Masters Theses

Computer stereo vision is used extract depth information from two aligned cameras and there are a number of hardware and software solutions to solve the stereo correspondence problem. However few solutions are available for inexpensive mobile platforms where power and hardware are major limitations. This Thesis will proposes a method that competes with an existing OpenCV stereo correspondence method in speed and quality, and is able to run on generic multi core CPU’s.

Design And Synthesis Of Boronic Acid-Based Sensors For Microarray Analysis And Fret-Detection To Study Carbohydrates, Yilin Wang

Masters Theses

Carbohydrates play significant roles in various biological and pathological processes such as cancer metastasis and inflammation. They participate in various signaling pathways and are able to bind to a litany of biological receptors such as proteins and viruses. Biologists have known for decades that the structure of glycans changes with the onset of cancer and inflammation. Due to these important activities, carbohydrate sensing has long been a focus of research. One example of such a carbohydrate sensor is boronic acid-based sensors. Boronic acid-based sensors are of particular interest due to their selectivity for 1,2- or 1,3-diols. A variety of techniques …

Communicating Sustainable Design Through Visual Dynamics, Phillip Walter Zawarus

Masters Theses

My thesis is the exploration of dynamic methods to eff ectively visualize and communicate sustainable designpractices. Every site consists of temporal conditions (climate, vegetation growth, hydrology, comfort, aesthetics)that require dynamic representation of it’s progressive state. By understanding both the quantitative and qualitivemeasures of a site’s content, designers can begin to create guidelines and adaptive responses to the changingconditions. Th is can be achieved by fi rst understanding the intergrated relationship of those conditions, as oneelement has a direct or indirect impact on another. Th e design, in turn, cannot be a static implimentation butrather an evolutionary application.

Decay Estimates For Nonlinear Wave Equations With Variable Coefficients, Michael Jacob Roberts

Masters Theses

We studied the long time behavior of solutions of nonlinear wave equations with variable coefficients and an absorption nonlinearity. Such an equation appears in models for traveling waves in a non-homogeneous gas with damping that changes with position. We established decay estimates of the energy of solutions. We found three different regimes of decay of solutions depending on the exponent of the absorption term. We show the existence of two critical exponents. For the exponents above the larger critical exponent, the decay of solutions of the nonlinear equation coincides with that of the corresponding linear problem. For exponents below the …

Structural Control Of Fluvial Network Morphology On Titan, Sarah Alice Drummond

Masters Theses

Titan fluvial networks have been classed based on identification of network pattern morphology. Drainage network patterns have specific geologic implications, as the pattern is affected by regional slope, structures, and bedrock resistance. Qualitative identification of network patterns has resulted in a lack of consistent classifications for networks. In this work, a global map of fluvial features on Titan is presented with features delineated based on their appearance in Cassini Titan Radar Mapper synthetic aperture radar (SAR) data. The networks imaged by the Huygens Descent Imager/Spectral Radiometer (DISR) are also included in this work. Networks were classified using a quantitative terrestrial …

Contractible Theta Complexes Of Graphs, Chelsea Marian Mcamis

Masters Theses

We examine properties of graphs that result in the graph having a contractible theta complex. We classify such properties for tree graphs and graphs with one loop and we introduce examples of graphs with such properties for tree graphs and graphs with one or two loops. For more general graphs, we show that having a contractible theta complex is not an elusive property, and that any skeleton of a graph with at least three loops can be made to have a contractible theta complex by strategically adding vertices to its skeleton.

Higher-Order Corrections In Effective Theory Of Deformed Nuclei, Jialin Zhang

Masters Theses

The low-energy excitation bands of open-shell heavy nuclei have been accounted for by collective motion of the constituting nucleons. Macroscopically, heavy nuclei can be looked upon as deformed rotors undergoing surface vibration and rotation. Traditionally, deformed nuclei are described within the Bohr-Mottelson geometric model or the interacting boson model. An effective theory that exploits spontaneous symmetry breaking has recently been developed for axially deformed nuclei. It describes the rotational and vibrational degrees of freedom in terms of Nambu-Goldstone bosons and quadrupole phonons respectively, with a power counting based on their different energy scales. A systematic way to construct the rotationally …

Identifying The Spatial Distribution Of Three Plethodontid Salamanders In Great Smoky Mountains National Park Using Two Habitat Modeling Methods, Matthew Stephen Kookogey

Masters Theses

The main objective was to create habitat models of three plethodontid salamander species (Desmognathus conanti, D. ocoee, and Plethodon jordani) in GSMNP. To investigate the relationships between salamanders and their habitats, I used three models—logistic regression with use-availability sampling, logistic regression with case-control sampling, and Mahalanobis distance (D²)—for each species to gain a robust view of the relationships. The secondary objective was to compare the different modeling methods within and across the three species. Elevation was the dominant variable for all three species.

D² for D. conanti predicted low elevations, close proximity …

Spatial Discrepancies Between Nhdplus And Lidar-Derived Stream Networks, Nicole Marie Samu

Masters Theses

Many organizations demand that current water resource issues necessitate improved stream network mapping for more accurate and reliable watershed analysis and modeling results, which can ultimately enable better management and policy decisions. Stream network data from the National Hydrography Dataset Plus (NHDPlus) and derived from Light Detection and Ranging (LIDAR) are each widely accepted to be of superior quality compared to many other conventional datasets. Each dataset indicates potential to improve a wide range of water resource applications; NHDPlus for its high spatial accuracy and functionality, and LIDAR-derived networks for their high resolutions. NHDPlus is publicly available and widely used; …

Alexander And Conway Polynomials Of Torus Knots, Katherine Ellen Louise Agle

Masters Theses

We disprove the conjecture that if K is amphicheiral and K is concordant to K', then C_K'(z)C_K'(iz)C_K\(z²) is a perfect square inside the ring of power series with integer coefficients. The Alexander polynomial of (p,q)-torus knots are found to be of the form A_T(p,q)(t)= (f(t^q))/(f(t)) where f(t)=1+t+t²+...+t^p-1. Also, for (pⁿ,q)-torus knots, the Alexander polynomial factors into the form A_T(pⁿ ,q)=f(t)f(t^p)f(t^p2 )...f(t^pn-2 )f(t^pn-1 ). A new conversion from the Alexander polynomial to the …