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Masters Theses

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A Remote Sensing Investigation Of Elevated Sub-Horizontal Topographic Surfaces In The Wichita Mountains, Oklahoma, Liang Xue Jan 2014

A Remote Sensing Investigation Of Elevated Sub-Horizontal Topographic Surfaces In The Wichita Mountains, Oklahoma, Liang Xue

Masters Theses

"Multiple elevated horizontal to sub-horizontal topographic surfaces are present in the Wichita Mountains, Oklahoma. Elevated topographic surfaces, developed primarily on granite bedrock with gentle slopes of 0.5 to 7⁰,were investigated using 1) Digital Elevation Models (DEMs) extracted from NAD 27 UTM coordinates, 2) Google Earth imagery, and 3) USGS topographic maps. In the western Wichita Mountains prominent topographic surfaces at elevations of 720 ± 5 m, 685 ± 5 m, and 660 ± 5 m are well preserved on at least four different mountains (e.g., Solder's Peak, King Mt.) and can be correlated with similar surfaces on at least seven …


Investigation Of Angiogenic Effects Of Bioactive Borate Glass Microfibers And Beads In A Rodent Model, Richard Jeffrey Watters Jan 2014

Investigation Of Angiogenic Effects Of Bioactive Borate Glass Microfibers And Beads In A Rodent Model, Richard Jeffrey Watters

Masters Theses

"The primary objective of this research project was to evaluate the effects of three different compositions of bioactive glass microfibers (45S5, 13-93B3, and 13-93B3Cu) and bioactive glass beads (13-93, 13-93B3, and 13-93B3Cu) on angiogenesis in subcutaneous tissue in the SKH1 'hairless' mouse. Microvascular responses to the bioactive glass implants were investigated via three experimental approaches: noninvasive vital imaging of microvasculature in dorsal skin windows; quantitative histomorphometry of microvascular densities; and quantitative PCR measurements of mRNA expression of pro-angiogenic cytokines VEGF and FGF-2. The live imaging of dorsal skin window preparations in the hairless SKH1 showed the formation of a halo-like …


Determination Of Minor And Trace Elements Concentration In Kidney Stones Using Elemental Analysis Techniques, Anjali Srivastava Jan 2014

Determination Of Minor And Trace Elements Concentration In Kidney Stones Using Elemental Analysis Techniques, Anjali Srivastava

Masters Theses

"The determination of accurate material composition of a kidney stone is crucial for understanding the formation of the kidney stone as well as for preventive therapeutic strategies. Radiations probing instrumental activation analysis techniques are excellent tools for identification of involved materials present in the kidney stone. The X-ray fluorescence (XRF) and neutron activation analysis (NAA) experiments were performed and different kidney stones were analyzed. The interactions of X-ray photons and neutrons with matter are complementary in nature, resulting in distinctly different materials detection. This is the first approach to utilize combined X-ray fluorescence and neutron activation analysis for a comprehensive …


Methamphetamine Absorption By Skin Oils: Accumulated Mass, Partition Coefficients And The Influence Of Fatty Acids, Kristia Parker Jan 2014

Methamphetamine Absorption By Skin Oils: Accumulated Mass, Partition Coefficients And The Influence Of Fatty Acids, Kristia Parker

Masters Theses

"Occupants of former methamphetamine laboratories, often residences, may experience increased exposure through the accumulation of the methamphetamine in skin oil. The objectives of this study were to determine equilibrium partition coefficients of vapor-phase methamphetamine with artificial skin oil (ASO), artificial skin oil without fatty acids and real skin oil. A 10 L flow through stainless-steel chamber and in-line filter holders were used to expose skin-oil coated filters to vapor-phase methamphetamine at concentrations ranging from 12 ppb to 159 ppb and samples were analyzed for exposure time periods from 2 hours to 60 days. For a low vapor-phase methamphetamine concentration range …


Pn Anisotropy Tomography Of The Colorado Plateau And Adjacent Areas, Shengyao Cheng Jan 2014

Pn Anisotropy Tomography Of The Colorado Plateau And Adjacent Areas, Shengyao Cheng

Masters Theses

"The Pn tomography method utilizes seismic waves that refract along the Moho interface to perform inversion in order to investigate velocity anomalies and seismic anisotropy in the uppermost mantle. Results from Pn tomography can provide important information about the composition, temperature, and tectonic processes beneath the study area. Over the past decades, numerous seismic and geologic studies have been conducted in the Colorado Plateau and its adjacent areas to reveal crustal and mantle structures and processes responsible for the diverse surface geological features and tectonic events that have occurred in this area. To investigate lateral variations in the uppermost mantle …


Privacy Preservation Using Spherical Chord, Doyal Tapan Mukherjee Jan 2014

Privacy Preservation Using Spherical Chord, Doyal Tapan Mukherjee

Masters Theses

"Structured overlay networks are primarily used in data storage and data lookup, but they are vulnerable against many kinds of attacks. Within the realm of security, overlay networks have demonstrated applicability in providing privacy, availability, integrity, along with scalability. The thesis first analyses the Chord and the SALSA protocols which are organized in structured overlays to provide data with a certain degree of privacy, and then defines a new protocol called Spherical Chord which provides data lookup with privacy, while also being scalable, and addresses critical existing weaknesses in Chord and SALSA protocols. Spherical Chord is a variant of the …


Effect And Interactions Of Commercial Additives And Chloride Ion In Copper Electrowinning, Wenyuan Cui Jan 2014

Effect And Interactions Of Commercial Additives And Chloride Ion In Copper Electrowinning, Wenyuan Cui

Masters Theses

"This thesis is to understand and compare the effects and interactions of modified polysaccharide (HydroStar), polyacrylamide (Cyquest N-900) and chloride ion on copper electrowinning. A study of the nucleation and growth was conducted in a synthetic electrolyte (40 g/L Cu, 160 g/L H₂SO₄, 20 mg/L Cl-) with the addition of HydroStar or Cyquest N-900 using potential step measurements. The current responses generated were compared to theoretical models of nucleation and growth mechanisms. The nucleation and growth mechanism changed as function of potential and the presence of organic additives. The nucleation and growth mechanisms were confirmed using scanning electron microscopy (SEM). …


Modeling Of Multi-Terminal Vsc-Based Hvdc Systems, Mohammed Mabrook Alharbi Jan 2014

Modeling Of Multi-Terminal Vsc-Based Hvdc Systems, Mohammed Mabrook Alharbi

Masters Theses

"Improving the efficiency and operation of power transmission is important due to the continual increase in demand for electric power. In addition, many remote areas throughout the world lack sufficient access to electricity. Unfortunately, utilities cannot satisfy the high demand of power by building new power stations because of economic and environmental reasons. However, utilities can increase generation and transmission line efficiencies by controlling the power flow through their systems. One new attractive technology that enables the control of power flow in the system is Voltage-Source-Converter High Voltage Direct Current (VSC-HVDC) transmission.

Multi-terminal-HVDC (M-HVDC) can be built using VSC technology. …


Data Mining And Statistical Analysis Of Completions In The Canadian Montney Formation, Mustafa Adil Al-Alwani Jan 2014

Data Mining And Statistical Analysis Of Completions In The Canadian Montney Formation, Mustafa Adil Al-Alwani

Masters Theses

"This thesis documents a data-mining study and statistical analysis of well completion methods and their impact on production for more than 3300 horizontal wells in the Canadian Montney resource play.

The statistical software JMP is used to analyze well and production data for both horizontal Montney gas and oil wells, examining production trends with changes in completion parameters, such as the type of completion, fluid volume pumped, proppant load, number of fracture stages and completion costs. The analysis also provides a general understanding of average treatment characteristics, and how completions have changed with time for the Montney play.

Among the …


Crime Pattern Detection Using Online Social Media, Raja Ashok Bolla Jan 2014

Crime Pattern Detection Using Online Social Media, Raja Ashok Bolla

Masters Theses

"In this research, we show online social networks can be used to study crime detection problems. Crime is defined as an act harmful not only to the individual involved, but also to the community as a whole. It is also a forbidden act that is punishable by law. Crimes are social nuisances that place heavy financial burdens on society. Here we look at use of data mining followed by sentiment analysis on online social networks, to help detect the crime patterns. Twitter is an online social networking and microblogging service that enables users to post brief text updates, also referred …


Effects Of Grain Properties And Compaction On Single-Tool Normal Indentation Of Granular Materials, Dennis Chieze Duru Jan 2014

Effects Of Grain Properties And Compaction On Single-Tool Normal Indentation Of Granular Materials, Dennis Chieze Duru

Masters Theses

"The behavior of three granular materials; filter sand, crushed garnet, and shale cutting, were investigated in an effort to evaluate the effect of grain size and shape, and material compaction under single tool load-indentation test. Force-penetration data was collected continuously through the end of each test and specific energy and specific penetration was calculated from the data.

Grain size and compaction affected the force penetration behavior. The higher the grain size, the more the fluctuation in the force of penetration. In addition, compaction reduces the force fluctuation in the fine aggregate grains, but increases the magnitude of the force fluctuations …


Microwave Assisted Reconstruction Of Optical Interferograms For Distributed Fiber Optics Sensing & Characterization Of Pcb Dielectric Properties Using Two Striplines On The Same Board, Lei Hua Jan 2014

Microwave Assisted Reconstruction Of Optical Interferograms For Distributed Fiber Optics Sensing & Characterization Of Pcb Dielectric Properties Using Two Striplines On The Same Board, Lei Hua

Masters Theses

"A new concept, the microwave-assisted reconstruction of an optical interferogram for distributed sensing, was developed to resolve both the position and reflectivity of each sensor along an optical fiber. This approach involves sending a microwave-modulated optical signal through cascaded fiber optic interferometers. The optical spectrum of each sensor can be reconstructed by sweeping the optical wavelength and detecting the modulation signal. A series of cascaded fiber optic extrinsic Fabry-Perot interferometric sensors was used to prove the concept. The microwave-reconstructed interferogram matched well with those recorded individually from a traditional optical spectrometer. The application of distributed strain measurement was also investigated. …


Characterization Of 304l Stainless Steel By Means Of Minimum Input Energy On The Selective Laser Melting Platform, Ben Brown Jan 2014

Characterization Of 304l Stainless Steel By Means Of Minimum Input Energy On The Selective Laser Melting Platform, Ben Brown

Masters Theses

"Developing parameter sets for new materials on the Selective Laser Melting (SLM) platform has traditionally been done through the use of single line processing windows and a basic design of experiments (DOE) which would include varying machine parameters to maximize density. This study expands the traditional method by determining the main effects statistically for density, allowing for a more in depth analysis wherein the experimental results are statistically correlated to the variable machine parameters used. With this analysis, parameter optimization with respect to achieving near full density, while also considering build rates, can be performed. New parameters for 304L stainless …


Energy Efficient Scheduling And Allocation Of Tasks In Sensor Cloud, Rashmi Dalvi Jan 2014

Energy Efficient Scheduling And Allocation Of Tasks In Sensor Cloud, Rashmi Dalvi

Masters Theses

"Wireless Sensor Network (WSN) is a class of ad hoc networks that has capability of self-organizing, in-network data processing, and unattended environment monitoring. Sensor-cloud is a cloud of heterogeneous WSNs. It is attractive as it can change the computation paradigm of wireless sensor networks. In Sensor-Cloud, to gain profit from underutilized WSNs, multiple WSN owners collaborate to provide a cloud service. Sensor Cloud users can simply rent the sensing services which eliminates the cost of ownership, enabling the usage of large scale sensor networks become affordable. The nature of Sensor-Cloud enables resource sharing and allows virtual sensors to be scaled …


Development And Characterization Of Spiral Additions In A Ceramic Matrix, Andrea Lynn Els Jan 2014

Development And Characterization Of Spiral Additions In A Ceramic Matrix, Andrea Lynn Els

Masters Theses

"A novel spiral architecture was formed using titanium diboride and silicon carbide ceramics as either the spiral or matrix phase. Particulate composites with the same compositions were fabricated to compare to the materials in this study. Spiral additions were formed using powder loaded polymers followed by a single and/or multi-filament co-extrusion. For 25 vol% SiC spiral additions to TiB2, boron nitride was added to the SiC spiral to alter the bonding at the interface and reduce thermal residual stresses. All samples were hot-pressed to near full density at 1980 ⁰C. Hot pressed multi-filament co-extrusion of 2.4 mm / …


A Modified Initiation And Cut Profile Study Of The 10500 Grain Per Foot Linear Shaped Charge, Matthew Ortel Jan 2014

A Modified Initiation And Cut Profile Study Of The 10500 Grain Per Foot Linear Shaped Charge, Matthew Ortel

Masters Theses

"A 10,500 grain per foot (gr/ft.) linear shaped charge (LSC) was developed to cut targets that were too thick for smaller LSC. The manufacturer observed shallower penetration from the 10,500 gr/ft. LSC than was expected. This prompted investigations to uncover the cause of the perceived reduced performance.

A study performed at the Missouri University of Science and Technology changed the initiation method of the 10,500 gr/ft. charge to increase the cut performance of the charge. A modified two point, single end initiation method was devised and tested. This initiation method was termed "dual initiation" and focused on creating a planar …


Adsorption And Desorption Capacity Of Methamphetamine In Gypsum Drywall, Hongwan Li Jan 2014

Adsorption And Desorption Capacity Of Methamphetamine In Gypsum Drywall, Hongwan Li

Masters Theses

"Drywall (gypsum boards) commonly used in buildings can adsorb indoor air pollutants and release them later exposing occupants over long periods of time. Methamphetamine is a drug of abuse that contaminates building materials in many homes, including painted drywall. The objective of this study is to quantify the meth-gypsum equilibrium partition coefficient, Keq. This partition coefficient is defined as the mass of meth adsorbed per volume of gypsum per mass-concentration of gas-phase meth and has these units: (µg meth/m3 gypsum)/(µg meth/m3 air). The steady state equilibrium partition coefficient ranges from 1.1 to 3.0x105 for one …


Shear-Wave Splitting And Mantle Deformation Beneath The Western Tibetan Plateau, Melissa Ann Ray Jan 2014

Shear-Wave Splitting And Mantle Deformation Beneath The Western Tibetan Plateau, Melissa Ann Ray

Masters Theses

"The Tibetan Plateau has been an enigma to the scientific community since scientists first began to focus their attention on the area. Numerous studies over the decades were conducted to address how the plateau formed, mostly in the central and eastern portions of the Tibetan Plateau. Many questions still remain regarding the western Tibetan Plateau, and this study will add constraints to the mechanisms which regulated the formation of the plateau.

Data was acquired from over 13,000 measurements from 172 stations covering the western region of the plateau encompassing the Qiangtang Terrane, the Lhasa Terrane, and the Himalayan Orogenic Zone. …


Shear Behavior Of High Strength Self-Consolidating Concrete In Nu Bridge Girders, Alexander Michael Griffin Jan 2014

Shear Behavior Of High Strength Self-Consolidating Concrete In Nu Bridge Girders, Alexander Michael Griffin

Masters Theses

"As the nation's infrastructure continues to age, advanced concrete technologies have been developed to both reduce a structure's costs and increase its life expectancy. Since the early 1990's, self-consolidating concrete (SCC) has been one of these technologies. Many, however, have been reluctant to implement SCC in highway girders due to the mixture constituents. One of these concerns is the reduced content and size of the coarse aggregate. These differences in the concrete potentially hinder SCC's mechanical properties and shear resistance. Additionally, for high strength concretes (HSC) with weaker aggregates, shear cracks tend to propagate through the coarse aggregate, reducing the …


An Iterative Algorithm For Variational Data Assimilation Problems, Xin Shen Jan 2014

An Iterative Algorithm For Variational Data Assimilation Problems, Xin Shen

Masters Theses

"Data assimilation is a very powerful and efficient tool to use collected raw data for improving model prediction in numerical weather forecasting, hydrology, and many other areas of geosciences. In this thesis, an iterative algorithm [23] of variational data assimilation with finite element method is utilized to study different models. One motivation for this fundamental mathematical study is to provide a potential tool for simulation of CO2 sequestration by extending it to more realistic and sophisticated models in the future. The basic idea of variational data assimilation is to utilize the framework of optimal control problems. We apply the …


The Use Of Statistics And Its Analysis In Resolving Transportation Related Problems, Venkat Sravan Kothapalli Jan 2014

The Use Of Statistics And Its Analysis In Resolving Transportation Related Problems, Venkat Sravan Kothapalli

Masters Theses

"Statistical methods are traditionally used to summarize or describe a collection of data. This can be termed as descriptive statistics. This research focuses on application of certain statistical approaches, tools to solve transportation related problems. This research focuses on usage of statistical analysis in determine some of the significant factors and assumptions which should be taken into consideration while developing safety and maintenance related measures by transportation agencies. This research mainly focuses on; testing null hypothesis and frequency analysis. The research therefore is presented in two different case studies: 1) Statistical analysis of the work zone crash historical raw data …


Hedge Fund Replication Using A Strategy Specific Modeling Approach, Sujit Subhash Jan 2014

Hedge Fund Replication Using A Strategy Specific Modeling Approach, Sujit Subhash

Masters Theses

"Institutional investors and wealthy individuals have in the past allocated a significant portion of their portfolios to hedge funds with the expectation of unconditional and uncorrelated returns to the market. However, the financial crisis of 2008 has heightened investor sensitivity to the high fees, illiquidity, and lockup periods typically associated with hedge funds. Hedge fund indexes showing excellent returns and low volatility contain funds that are closed to new investments, while the performance of investable funds have been shown to be inferior to their non-investable counterparts. The lack of transparency and extreme variation in the performance of hedge funds make …


On Temporal And Frequency Responses Of Smartphone Accelerometers For Explosives Detection, Srinivas Chakravarthi Thandu Jan 2014

On Temporal And Frequency Responses Of Smartphone Accelerometers For Explosives Detection, Srinivas Chakravarthi Thandu

Masters Theses

"The increasing frequency of explosive disasters throughout the world in recent years have created a clear need for the systems to monitor for them continuously for better detection and to improve the post disaster rescue operations. Dedicated sensors deployed in the public places and their associated networks to monitor such explosive events are still inadequate and must be complemented for making the detection more pervasive and effective. Modern smart phones are a rich source of sensing because of the fact that they are equipped with wide range of sensors making these devices an appealing platform for pervasive computing applications. The …


Influence Of Erosional Unloading On The State Of Stress For Low Amplitude Single-Layer Buckle Folds - Implications For Tensile Fracture Occurrence, Mengke Li Jan 2014

Influence Of Erosional Unloading On The State Of Stress For Low Amplitude Single-Layer Buckle Folds - Implications For Tensile Fracture Occurrence, Mengke Li

Masters Theses

"The existence of fractures associated to buckle folds is related to the strain distribution of the fold. The erosional unloading process can amplify the remnant strain in the folded layer. Two-dimensional plane strain Finite Element Analysis (FEA) is used to investigate the influence of the erosional unloading step on both the evolution of the state of stress and the associated failure patterns in low amplitude buckle folds. Sensitivity analyses on different input parameters, including viscosity, shortening ratio, and overburden pressure, are performed. Based on the simulation results, tensile stress can be initiated both in the crest and in the limb …


Polyurethane Foam Infill For Fiber Reinforced Polymer (Frp) Bridge Deck Panels: An Evaluation Of Core Alternatives Using Small Scale Experimental Testing, Matthew Scott Hopkins Jan 2014

Polyurethane Foam Infill For Fiber Reinforced Polymer (Frp) Bridge Deck Panels: An Evaluation Of Core Alternatives Using Small Scale Experimental Testing, Matthew Scott Hopkins

Masters Theses

"Fiber reinforced polymer (FRP) decking is a concept that has been explored in recent decades as one solution to the performance issues of conventional concrete bridge decking. Many sandwich panel designs made of glass reinforced polyester or vinyl ester resin have been well developed, and manufactured using filament winding, hand lay-up, and extrusion methods. The major benefits of these panels was their light weight, corrosion resistance, fatigue performance, and potential for rapid field assembly. However, high initial costs coupled with small state budgets have kept them from main stream adoption. A viable alternative, is a foam/reinforced foam core sandwich panel …


"Green" On-Chip Inductors In Three-Dimensional Integrated Circuits, Umamaheswara Rao Tida Jan 2014

"Green" On-Chip Inductors In Three-Dimensional Integrated Circuits, Umamaheswara Rao Tida

Masters Theses

"This thesis focuses on the technique for the improvement of quality factor and inductance of the TSV inductors and then on the utilization of TSV inductors in various on-chip applications such as DC-DC converter and resonant clocking. Through-silicon-vias (TSVs) are the enabling technique for three-dimensional integrated circuits (3D ICs). However, their large area significantly reduces the benefits that can be obtained by 3D ICs. On the other hand, a major limiting factor for the implementation of many on-chip circuits such as DC-DC converters and resonant clocking is the large area overhead induced by spiral inductors. Several works have been proposed …


Ecology Of A Declining Great Plains Fish, Fundulus Sciadicus, In The Missouri Ozarks, Gregory Travis Thompson Jan 2014

Ecology Of A Declining Great Plains Fish, Fundulus Sciadicus, In The Missouri Ozarks, Gregory Travis Thompson

Masters Theses

"Anthropogenic habitat disturbances are of growing concern due to their impacts on native biota, especially in freshwater ecosystems. Damming, channelization, urbanization, wetland draining, and non-native fish introductions all play large roles in habitat homogeneity, fragmentation, and species competition. This has negative effects on native fish and invertebrate species. In the Midwestern United States, the plains topminnow (Fundulus sciadicus) has been declining across its range, to the point of becoming a species of special concern in Missouri. This is possibly due to a combination of the above anthropogenic habitat disturbances. To better understand the ecology of the plains topminnow …


Top-K With Diversity-M Data Retrieval In Wireless Sensor Networks, Kiran Kumar Puram Jan 2014

Top-K With Diversity-M Data Retrieval In Wireless Sensor Networks, Kiran Kumar Puram

Masters Theses

"Wireless Sensor Network is a network of a few to several thousand sensors deployed over an area to sense data and report that data back to the base station. There are many applications of wireless sensor networks including environment monitoring, wildlife tracking, troop tracking etc. The deployed sensors have many constraints like limited battery, limited memory and very little processing capacity. These constraints show direct effect on the network life time.

In many applications of Wireless Sensor Networks, such as monitoring chemical leak, the user is not interested in all the data points from the entire region, but may want …


Performance Comparison Of Transverse And Longitudinal Fractured Horizontal Wells Over Varied Reservoir Permeability, Fen Yang Jan 2014

Performance Comparison Of Transverse And Longitudinal Fractured Horizontal Wells Over Varied Reservoir Permeability, Fen Yang

Masters Theses

"Since the first application in the mid-1980's, multiple fractured horizontal wells have proven to be an effective means of extracting hydrocarbons. These wells require careful consideration of wellbore orientation relative to the horizontal principle stress. Wellbore orientation can lead to transverse fractures which are perpendicular to the wellbore, or longitudinal fractures parallel the wellbore. Questions arise regarding whether one fracture orientation is consistently preferred over the other, or if certain conditions affect the choice.

Historical work has examined the impact of horizontal wellbore azimuth in the Barnett and Marcellus Shale where public data was reviewed and statistical well analysis was …


Fabrication Of Glass Fiber-Reinforced Transparent Composites Using Vacuum Assisted Resin Transfer Molding Process, Gregory A. Taylor Jan 2014

Fabrication Of Glass Fiber-Reinforced Transparent Composites Using Vacuum Assisted Resin Transfer Molding Process, Gregory A. Taylor

Masters Theses

"The most commonly used transparent material is glass. Traditionally, glass is not desired for applications involving a low weight material while preserving high strength such as aerospace and military applications where armor must also be transparent. Some applications may include aircraft canopies and other vehicle windows. Development of a reliable transparent composite would fill a need for many of these applications where a transparent structure must both be strong and lightweight. A transparent polymer reinforced with a glass fiber fabric is a viable solution. To ensure transparency, both fiber and matrix must match in refractive index.

In the present work, …