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Masters Theses

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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. …


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 …


Shielding Effectiveness (Se) Measurement For Maxair Waveguide Panel, Lossy Material Evaluation By Laptop Application, Xiao Li Jan 2014

Shielding Effectiveness (Se) Measurement For Maxair Waveguide Panel, Lossy Material Evaluation By Laptop Application, Xiao Li

Masters Theses

"The first part of the thesis presents the EM shielding effectiveness (SE) measurement of new kind of waveguide panel, MaxAir, which based on metal coating technology. SE Measurement tell the SE performance of MaxAir compared to the traditional metal waveguide panel. In terms of good features such as lower price, less weight, MaxAir could replace traditional waveguide panel in some applications by its SE results. There are two SE measurement methods are performed for MaxAir panel, both of them based on reverberation chamber. Measured SE for several MaxAir panel samples in different cell dimension and coating configuration. By the Measured …


Experimental Investigation Of The Pebble Bed Structure By Using Gamma Ray Tomography, Fadha Shakir Ahmed Jan 2014

Experimental Investigation Of The Pebble Bed Structure By Using Gamma Ray Tomography, Fadha Shakir Ahmed

Masters Theses

"Pebble Bed Reactors offer a future for new nuclear energy plants. They are small, inherently safe, and can be competitive with fossil fuels. The fuel forms a randomly stacked pebble with non-uniform fuel densities. The thermal-mechanical behavior of pebble bed reactor core is depends strongly on the spatial variation of packing fraction in the bed and in particular on the number of contacts between pebbles, and between the pebbles and the blanket walls. To investigate these effects, experimental data to characterize bed structure are needed along with other numerical simulation and computational tools for validation.

In this study, a powerful …


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 …


The Effects Of Advanced Structural Materials To Mitigate Explosive And Impact Threats, Caleb Michael Baumgart Jan 2014

The Effects Of Advanced Structural Materials To Mitigate Explosive And Impact Threats, Caleb Michael Baumgart

Masters Theses

"In a world of ever newer and modified improvised explosive devices (IEDs) that are very common in certain parts of the world, it is always more important to improve the devices used for protection. This research endeavors to design and analyze a blast barrier using three different media types to mitigate the high pressures from an IED or a car bomb. The three media types used in this research are pumice, steel grit, and foam. Six barriers were built to test the three media types and account for the changes from a standard solid concrete barrier to a barrier with …


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 …


Data Analysis And Summary For Surfactant-Polymer Flooding Based On Oil Field Projects And Laboratory Data, Pratap D. Chauhan Jan 2014

Data Analysis And Summary For Surfactant-Polymer Flooding Based On Oil Field Projects And Laboratory Data, Pratap D. Chauhan

Masters Theses

"Enhanced oil recovery screening is considered as an important first step towards evaluating a potential EOR technique for a candidate reservoir. A vast amount of research is continuously been conducted in EOR. Therefore, it is imperative to update the screening criteria regularly.

This study involves updating the screening criteria for surfactant polymer flooding for field projects dataset and laboratory dataset. Many of the screening criteria for surfactant-polymer flooding in the literature were achieved on the basis of data collected from the EOR surveys published biennially in Oil & Gas Journals. However, these datasets contain problems like missing data and inconsistent …


Behavior In Air Leakage And Recirculation Under The Influence Of Booster Fans, Koziba Feledi Jan 2014

Behavior In Air Leakage And Recirculation Under The Influence Of Booster Fans, Koziba Feledi

Masters Theses

"A booster fan is an underground mechanical ventilation equipment installed in series with a main surface fan that is used to boost the air pressure provided by the surface main fan passing through it. As mining continues to expand and go deeper, the need for improved and efficient ventilation increases. This has led to the use of booster fans and other auxiliary ventilation devices in underground mines. Research defining how system leakage and recirculation are affected by booster fans; describing how system leakage and recirculation are affected by the location, placement, and amount of air pressure from the booster fans; …


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 …


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 …


Gel Treatment Field Application Survey For Water Shut Off In Production Wells, Jingyi Liao Jan 2014

Gel Treatment Field Application Survey For Water Shut Off In Production Wells, Jingyi Liao

Masters Theses

"Enhanced oil recovery (EOR) screening criteria are considered as a guideline for candidate evaluation and determination. Not many screening criteria for gel treatment had been published. Some published gel treatment application surveys for water shut off only include limited number of oil fields and locations.

The current work aims to summarize the worldwide gel treatment applications for water shut off in production wells by creating and analyzing a dataset from a variety of sources. This study started from collecting and cleaning the gel treatment application data. All the data were from SPE field publications from 1990 to 2012 and from …


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 …


Small-Signal Modeling Of Grid-Supporting Inverters In Droop Controlled Microgrids, Jacob Andreas Mueller Jan 2014

Small-Signal Modeling Of Grid-Supporting Inverters In Droop Controlled Microgrids, Jacob Andreas Mueller

Masters Theses

"An approach to modeling externally controlled inverters in droop controlled microgrids is presented. A generic three-phase grid-tied inverter and control system model is derived in synchronous reference frame. The structure of this inverter is intended to be similar in composition to other three-phase inverters whose models and dynamics are well understood. This model is used as a starting point in the development of a more comprehensive model, which is capable of representing the coupling between complex power, bus voltage, and frequency that occurs in a microgrid. This new model is a combination of the generic inverter and an autonomous, grid-forming …


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 …


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 …


Use On Multinomial Logistic Regression In Work Zone Crash Analysis For Missouri Work Zones, Paul Robin Jan 2014

Use On Multinomial Logistic Regression In Work Zone Crash Analysis For Missouri Work Zones, Paul Robin

Masters Theses

"This study focuses on the use of statistical data analysis procedures in identifying factors which affect the severity of crashes in work zones. Work zones are unsafe for the traffic passing through as well as the workers. Multinomial Logistic Regression has been used to analyse Missouri work zone crash data to identify significant factors which affect the severity of crashes. This particular type of regression analysis was used due to the mixed nature of data. Multinomial regression was used to compare crashes with severity Property Damage Only against crashes with Minor Injuries and Disabling Injuries/ Fatal. The factors considered were …


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 …


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 …


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 …


Performance Evaluation Of Coaxial Horizontal Axis Hydrokinetic Turbines System, Abdulaziz M. Abutunis Jan 2014

Performance Evaluation Of Coaxial Horizontal Axis Hydrokinetic Turbines System, Abdulaziz M. Abutunis

Masters Theses

"Hydrokinetic energy technologies are emerging as a viable solution for renewable power generation. Unlike conventional hydropower turbines, hydrokinetic turbines are environmentally friendly; they operate at zero-head, and do not need dams to preserve the water. Unfortunately, they have a low efficiency which makes their design a challenging task. This work was focused on the hydrodynamic performance of horizontal axis hydrokinetic turbines (HAHkTs) under different turbine arrangements and flow conditions.

It was undertaken in an effort to improve the efficiency of small HAHkTs that harness a river's kinetic energy. Four sets of experiments were performed in a water tunnel to investigate …


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, …


Inorganic Biodegradable Devices For Temporary Implants, Kassan Unda Jan 2014

Inorganic Biodegradable Devices For Temporary Implants, Kassan Unda

Masters Theses

"Implantable electronic devices have great potential to benefit many health care technologies. They comprise of two different categories. The first is permanent prosthetic devices like cardiac pacemakers or nerve stimulants. The other category includes temporary devices for interventional medical monitoring and control scenarios, which lose functionality and become unnecessary after their intended operational lifetime. This can cause serious electromagnetic and biomechanical safety concerns if not removed from the body by an additional surgical operation.

This thesis focuses on exploring the feasibility of implantable inorganic bioresorbable thin film resistive devices utilizing bioactive glass as the core structural material. This device will …


Interleaved Coupled-Inductor Boost Converter With Multiplier Cell And Passive Lossless Clamp, Stephen C. Moerer Jan 2014

Interleaved Coupled-Inductor Boost Converter With Multiplier Cell And Passive Lossless Clamp, Stephen C. Moerer

Masters Theses

"As photovoltaic panels become a more dominant technology used to produce electrical power, more efficient and efficacious solutions are needed to convert this electrical power to a useable form. Solar microconverters, which are used to convert a single panel's power, effectively overcome issues such as shading and panel-specific maximum power point tracking associated with traditional solar converters which use several panels in series. This thesis discusses a high gain DC-DC converter for incorporating single low-voltage solar panels to a distribution level voltage present in a DC microgrid. To do this, a converter was developed using coupled inductors and a capacitor-diode …


Machinability Improvement During High-Speed End-Milling Of Inconel 718 Alloy, Chukwujekwu Nnadi Jan 2014

Machinability Improvement During High-Speed End-Milling Of Inconel 718 Alloy, Chukwujekwu Nnadi

Masters Theses

“This thesis presents the results of the experimental investigation of the effects of machining parameters (spindle speed and feedrate) and cooling strategies [Minimum Quantity Lubrication (MQL), Cryogenic Liquid Nitrogen (LN2), and combined (MQL+LN2)] on cutting force components, cutting temperature, tool wear and surface roughness during high-speed slot end-milling of Inconel 718 alloy. In addition, a comparative evaluation of the three cooling strategies was conducted for cutting force components, surface roughness and residual stresses. All end-milling experiments were conducted on a Cincinnati Milacron Vertical Machining center (VMC), using a 0.5 inch (12.7 mm) diameter, 0.03 inch (0.762 …


The Importance Of Being Ancillary: The Cold War Context Of Fort Greely, Alaska, Catherine Hardee Jan 2014

The Importance Of Being Ancillary: The Cold War Context Of Fort Greely, Alaska, Catherine Hardee

Masters Theses

This thesis discusses the history of a remote Army base in Alaska, Fort Greely, from its beginnings as a World War II stopover for Lend-Lease aircraft to its rebirth as a Cold War installation, as well as its role in testing and training for cold weather missions and Cold War scientific endeavors. It also examines the role played by Fort Greely in the Cold War, and its historical significance in that era.


The Effect Of Using Different Rock Failure Criteria In Wellbore Stability Analysis, Reza Rahimi Jan 2014

The Effect Of Using Different Rock Failure Criteria In Wellbore Stability Analysis, Reza Rahimi

Masters Theses

"Determination of the appropriate drilling fluid density by rock failure analysis is an essential step to control wellbore instability. To determine wellbore failure stresses, the rock strength has to be known, an appropriate constitutive model has to be selected, and finally an accurate rock failure criterion must be chosen. Linear-poro elastic modeling of the mechanical wellbore failure is the most common approach to investigate wellbore instability. Numerous failure criteria have been used for the rock failure analysis but there is not any commonly accepted agreement of which failure criteria to use. Rock failure criteria differ in two main characteristics. First, …


Mechanistic Identification Of Specific Force Coefficients In Endmilling Inconel 718 Under Four Cooling Strategies, Mahmood Shaman Ameen Jan 2014

Mechanistic Identification Of Specific Force Coefficients In Endmilling Inconel 718 Under Four Cooling Strategies, Mahmood Shaman Ameen

Masters Theses

“This thesis presents the results of experimental investigations of the mechanistic identification of specific force coefficients for uncoated bull-nose and uncoated wavy-edge/bull-nose helical endmilling of Inconel 718 under emulsion, minimum quantity lubrication (MQL), cryogenic (LN2), and combined (MQL + LN2) cooling. Several slot milling tests were conducted on Inconel 718 workpiece block with depth of cut 1.25 mm. The cutting parameters were varied as: spindle speed, n = 250 and 750 rev/min, feedrate, f = 25–75 mm/min by using uncoated carbide bull-nose helical endmill. Also 24 peripheral milling tests were conducted on Inconel 718 workpiece block …


Software-Based Instrumentation For Analysis Of Electrostatic Discharge Effects, Antonio James Sabatini Jan 2014

Software-Based Instrumentation For Analysis Of Electrostatic Discharge Effects, Antonio James Sabatini

Masters Theses

”Failures caused by electrostatic discharge (ESD) compromise the reliability of embedded systems. Peripherals such as the universal serial bus (USB) are particularly vulnerable, as isolating them to avoid electromagnetic interference would defy their purpose - facilitating communication with and/or by the embedded system. Better understanding the propagation of failures that result from ESD can facilitate defensive development of hardware and software for embedded systems, but is hampered by the lack of non-invasive and lightweight instrumentation techniques.

The original contribution of this thesis is the design and development of software-based instrumentation for monitoring the reaction of the USB peripheral of an …


Statistical Analysis Of Sleep Patterns In Drosophila Melanogaster, Luyang Wang Jan 2014

Statistical Analysis Of Sleep Patterns In Drosophila Melanogaster, Luyang Wang

Masters Theses

“Sleep is one of the most preserved and restorative behaviors of animals and is important in human health. Lack of sleep may cause numerous diseases. So the study of sleep rhythms is very essential and complicated. In order to simplify the process of studying sleep, the fruit fly Drosophila melanogaster, is utilized as a model organism for several reasons. Some of the molecular mechanisms that contribute to the circadian clock in the fruit fly were also found to generate similar cycles in mammals. In order to study sleep patterns in the fruit fly, experiments were designed and performed to …