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Masters Theses

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Application Of Millimeter-Wave Differential Probe For Crack Detection On Riveted Structures, Kuang Ping Ying Jan 2017

Application Of Millimeter-Wave Differential Probe For Crack Detection On Riveted Structures, Kuang Ping Ying

Masters Theses

"This thesis proposes the use of a W-band wideband differential probe for crack detection on riveted structures, such as aircraft fuselage lap joints. Detection of crack at its early stage (surface-breaking) is particularly important to prevent the development of a fatigue crack. This probe utilizing millimeter-wave frequencies serves as a viable candidate on detecting surface-breaking cracks, as it can be employed in measurements in a non-contact fashion, while allowing for high spatial-resolution images and the abilities to penetrate through dielectric materials (paint), making it attractive for detecting small cracks. In previous works, a V-band differential probe has shown promise for …


Crustal Thickness And Vp/Vs Ratio Of Yellowstone, Eastern Snake River Plain, Wyoming Province, And The Northern Basin And Range Province Through Receiver Function Analysis, Avikant Dayma Jan 2017

Crustal Thickness And Vp/Vs Ratio Of Yellowstone, Eastern Snake River Plain, Wyoming Province, And The Northern Basin And Range Province Through Receiver Function Analysis, Avikant Dayma

Masters Theses

"For decades, numerous studies have been conducted and contradictory results were achieved about the origin and evolution of the Yellowstone supervolcano and the Eastern Snake River Plain. Whether the 640 km long time-progressive chain of rhyolitic calderas was formed due to mantle-plume or a result of lithospheric extension allowing the emergence of melt on the surface is still a debate. Using receiver function analyses, this study determines the crustal thickness and the Vp/Vs ratio below the Yellowstone Plateau, Wyoming Province (WP), Idaho Batholith (IB), Eastern Snake River Plain (ESRP), and the northern Basin and Range Province (BRP). The thickness is …


Cathodic Protection Measurement Through Inline Inspection Technology Uses And Observations, Briana Ley Ferguson Jan 2017

Cathodic Protection Measurement Through Inline Inspection Technology Uses And Observations, Briana Ley Ferguson

Masters Theses

"This research supports the evaluation of an impressed current cathodic protection (CP) system of a buried coated steel pipeline through alternative technology and methods, via an inline inspection device (ILI, CP ILI tool, or tool), in order to prevent and mitigate external corrosion. This thesis investigates the ability to measure the current density of a pipeline's CP system from inside of a pipeline rather than manually from outside, and then convert that CP ILI tool reading into a pipe-to-soil potential as required by regulations and standards. This was demonstrated through a mathematical model that utilizes applications of Ohm's Law, circuit …


Study Of Surface Complexation And Mineral Dissolution During Water-Rock Interaction In High Salinity Waterflooding At Elevated Temperatures, Sameer Salasakar Jan 2017

Study Of Surface Complexation And Mineral Dissolution During Water-Rock Interaction In High Salinity Waterflooding At Elevated Temperatures, Sameer Salasakar

Masters Theses

"High salinity waterflooding for carbonate reservoirs is efficient and cheap method used for improved oil recovery. Various mechanisms have been proposed including adsorption/desorption on rock surface, mineral dissolution and precipitation, multicomponent ion exchange, interfacial tension reduction, fine migration and double layer expansion. These all process alter the wettability which leads to improved oil recovery.

Objective of this study was to understand processes that occur during water-rock interaction when high salinity water is flooded into the reservoir. In this work, effect of temperature on water-rock interaction is studied along with effect of pH and specific surface areas of calcite at normal …


Long-Term Monitoring Of A Landslide In Stone County, Missouri Using High Precision Multi-Temporal Laser Scanning, Benjamin Michael Herries Jan 2017

Long-Term Monitoring Of A Landslide In Stone County, Missouri Using High Precision Multi-Temporal Laser Scanning, Benjamin Michael Herries

Masters Theses

"A terrestrial laser scanning survey was conducted over the course of 1.5 years to test and validate a new target tracking method which characterizes the surface and subsurface behavior of soft slope landslides. Reflective spherical Styrofoam targets were mounted onto steel rods and driven into multiple levels of a landslide located in Stone County, Missouri. These targets were scanned a total of seventeen times over the course of the survey and were used as a proxy to measure the displacement of specific areas of the landslide. The three-dimensional point cloud data was processed through a software suite specifically developed to …


Depth Determination Method For A Trailer-Truck Test-Bed, Aditya Thakur Jan 2017

Depth Determination Method For A Trailer-Truck Test-Bed, Aditya Thakur

Masters Theses

"A camera is considered as a good sensing device to obtain visual information from its surrounding environment. In a three dimensional space, a camera has a two dimensional plane. Projection of an object on this plane creates a two dimensional projection and loses information of the third dimension. A single projection is not enough to retrieve the lost third dimensional information about the object. Thus it makes it difficult to use a single camera as a sensing instrument. In this project, we have developed a method that determines the three dimensional information using a single camera. The method utilizes an …


Geomechanical Analysis Of The Wellbore Instability Problems In Nahr Umr Formation Southern Iraq, Haider Qasim Mohammed Jan 2017

Geomechanical Analysis Of The Wellbore Instability Problems In Nahr Umr Formation Southern Iraq, Haider Qasim Mohammed

Masters Theses

"Wellbore instability problems play a major rule of increasing nonproductive time (NPT) during drilling processes. In most cases, the cost of drilling a well can be reduced by designing a suitable operational window using geomechanical models. Several wellbore instability problems have been encountered during drilling Nahr Umr Formation in an oil field in southern Iraq. These problems include but are not limited to, mechanical stuck, caving, and tight holes. Data from twenty vertical wells are investigated to reveal the major factors that control the instability problems and to design an optimum mud window. A geomechanical model is developed to determine …


In-Situ Control Of Substrate Temperature In Additive Manufacturing To Homogenize Micro-Hardness Of Laser Clad Deposits Using Thermo-Electric Cooling, Raghu Ram Kolla Jan 2017

In-Situ Control Of Substrate Temperature In Additive Manufacturing To Homogenize Micro-Hardness Of Laser Clad Deposits Using Thermo-Electric Cooling, Raghu Ram Kolla

Masters Theses

”Nickel hard-surfacing alloys are replacing hard Chromium coatings due to their excellent wear and corrosion-resistant properties. In laser cladding of these alloys, however, these properties can vary across the height of the deposit due to an accumulation of excess heat generated in the deposit during the process. This may result in uneven wear of the clad parts which can be detrimental for practical purposes. The research objective is to develop an in-situ cooling system that works in line with the laser deposition system to extract the excess heat buildup and reduce the variation in the hardness of the Ni-based clad …


Automatic Discrimination Of Basal Cell Carcinoma From Sebaceous Hyperplasia Based On Image Processing Of Dermoscopy Images, Jonathan Liao Jan 2017

Automatic Discrimination Of Basal Cell Carcinoma From Sebaceous Hyperplasia Based On Image Processing Of Dermoscopy Images, Jonathan Liao

Masters Theses

“This project focuses on discriminating basal cell carcinoma from sebaceous hyperplasia using image processing techniques. Basal cell carcinoma is a kind of malignant skin cancer that needs to be treated; however, if diagnosed as sebaceous hyperplasia, a benign lesion which is a mimic of basal cell carcinoma, then it may not be treated properly. Through observation, white pouch-like areas within the lesion appear in sebaceous hyperplasia images; whereas in basal cell carcinoma images, white areas tend to be formed in a smashed irregular figure shape. Hence, utilizing image processing techniques to segment these white areas from the images and using …


An Investigation Of Borax For Sealing Inflow From Berea Sandstone, Tri-Tris Bao Nguyen Jan 2017

An Investigation Of Borax For Sealing Inflow From Berea Sandstone, Tri-Tris Bao Nguyen

Masters Theses

"Well inflow control is a major challenge for the oil and gas industry. Erle Haliburton revolutionized well inflow control with his patent for cementing oil wells in 1921. Soon after, cement became the accepted material to establish well integrity and has been ever since. Cement is used in all phases of the well life cycle, and it is expected to hold indefinitely once set. Yet based on the nature of cement and the placement techniques, flow pathways may develop from improper cementing jobs or from cement degradation over time. Well integrity is especially crucial for wellbore plugging and abandonment, since …


Multiple Security Domain Model Of A Vehicle In An Automated Vehicle System, Uday Ganesh Kanteti Jan 2017

Multiple Security Domain Model Of A Vehicle In An Automated Vehicle System, Uday Ganesh Kanteti

Masters Theses

"This thesis focuses on the security of automated vehicle platoons. Specifically, it examines the vulnerabilities that occur via disruptions of the information flows among the different types of sensors, the communications network and the control unit in each vehicle of a platoon. Multiple security domain nondeducibility is employed to determine whether the system can detect attacks. The information flows among the various domains provide insights into the vulnerabilities that exist in the system by showing if an attacker’s actions cannot be deduced. If nondeducibility is found to be true, then an attacker can create an undetectable attack. Defeating nondeducibility requires …


Multiple Security Domain Nondeducibility Air Traffic Surveillance Systems, Anusha Thudimilla Jan 2017

Multiple Security Domain Nondeducibility Air Traffic Surveillance Systems, Anusha Thudimilla

Masters Theses

"Traditional security models partition the security universe into two distinct and completely separate worlds: high and low level. However, this partition is absolute and complete. The partition of security domains into high and low is too simplistic for more complex cyber-physical systems (CPS). Absolute divisions are conceptually clean, but they do not reflect the real world. Security partitions often overlap, frequently provide for the high level to have complete access to the low level, and are more complex than an impervious wall. The traditional models that handle situations where the security domains are complex or the threat space is ill …


Evaluation Of Preformed Particle Gel As A Diverting Agent For Acidizing, Bo Wei Jan 2017

Evaluation Of Preformed Particle Gel As A Diverting Agent For Acidizing, Bo Wei

Masters Theses

"Preformed particle gels (PPGs) have been developed and successfully used to improve conformance in heterogeneous reservoirs. However, no research has been reported to show their potential diverting applications in acidizing because of their unknown performance in this process. This work targets on evaluating the potential of PPGs to be used as diverting agents and factors influencing the diverting performance.

The swelling properties of three types of PPGs (PPG #1, #2, and #3) were first studied in brine and acid, including the swelling kinetics and equilibrium, PPG strength, and deswelling performance. Effects of different brine concentration, acid concentration, and temperature were …


Overview Of Co₂ Leakage Problems And Sealants For Co₂ Leakage Remediation, Shudai Peng Jan 2017

Overview Of Co₂ Leakage Problems And Sealants For Co₂ Leakage Remediation, Shudai Peng

Masters Theses

"Excessive Carbon Dioxide (CO₂) emission has become a serious issue and caused lots of environmental problems. Carbon Capture and Storage (CCS) program has been developed to reduce the CO₂ content in the atmosphere. CO₂ storage has been targeted mainly on depleted oil or gas reservoirs and deep saline aquifers. However, leakage could occur through wellbores, cap rocks, formation faults, and fractures during and after CO₂ injection. To minimize the risk, different types of sealants have been investigated to prevent CO₂ leaks. The aim of this thesis is to provide a comprehensive review of the materials which could be used as …


Combined Flue Gas Cleanup Process For Simultaneous Removal Of SoX, NoX, And Co₂ -- A Techno-Economic Analysis, Amit Narendrasing Hajari Jan 2017

Combined Flue Gas Cleanup Process For Simultaneous Removal Of SoX, NoX, And Co₂ -- A Techno-Economic Analysis, Amit Narendrasing Hajari

Masters Theses

"Flue gas cleanup often requires the removal of SOx, NOx and CO2 in separate units before atmospheric emission. The step-wise treatment process currently in place incurs significant cost and energy penalty. A single-step adsorption process based on pressure swing adsorption (PSA) by which these impurities are removed is envisioned as an efficient means of flue gas cleanup that can be applied relatively easily. In this study, the technological and economic feasibility of a single-step separation process in which SOx, NOx and CO2 are simultaneously removed from flue gas streams are assessed. Capital …


A Bounded Actor-Critic Algorithm For Reinforcement Learning, Ryan Jacob Lawhead Jan 2017

A Bounded Actor-Critic Algorithm For Reinforcement Learning, Ryan Jacob Lawhead

Masters Theses

"This thesis presents a new actor-critic algorithm from the domain of reinforcement learning to solve Markov and semi-Markov decision processes (or problems) in the field of airline revenue management (ARM). The ARM problem is one of control optimization in which a decision-maker must accept or reject a customer based on a requested fare. This thesis focuses on the so-called single-leg version of the ARM problem, which can be cast as a semi-Markov decision process (SMDP). Large-scale Markov decision processes (MDPs) and SMDPs suffer from the curses of dimensionality and modeling, making it difficult to create the transition probability matrices (TPMs) …


Student Veterans And Their Transition To Becoming A College Student, Paul R. Higgerson Jan 2017

Student Veterans And Their Transition To Becoming A College Student, Paul R. Higgerson

Masters Theses

This study sought to understand how student veterans view their transition to becoming a college student. A small, but increasing, amount of studies have been conducted on this topic. A qualitative approach, specifically a narrative method, was utilized to better understand how student veterans made meaning of the life events they experienced during their transition. Six student veterans in at least their second semester at their current institution were interviewed one-on-one, and their narratives are included here. This study revealed that student veterans and adult learners share many characteristics and that by viewing the student veteran as a student in …


A Study Of Acoustic Reflections To Determine The Location, Size, Shape, And Orientation Of Reflecting Objects, Brandon M. Heller Jan 2017

A Study Of Acoustic Reflections To Determine The Location, Size, Shape, And Orientation Of Reflecting Objects, Brandon M. Heller

Masters Theses

This study was conducted to examine the properties of sound in relation to echolocation, specifically in relation to its use by humans. Through my thesis, objects of varying shape and size were subjected to a sound wave to determine details about the object from the reflected sound. The shapes' comparisons were conducted at varying distances, measuring the intensity of the returning sound wave at several frequencies. The results demonstrated a correlation between the intensity of the sound in regards to distances, area of the reflector, and the shape of the reflector.


Molecular Recognition Profiles Of Molecular Cocrystals, Ian C. Tinsley Jan 2017

Molecular Recognition Profiles Of Molecular Cocrystals, Ian C. Tinsley

Masters Theses

The manner in which molecules recognize each other holds critical importance to nearly every area of science. This significance stems from the key underpinning of molecular assembly to our most basic understanding of chemical processes. Whether these interactions relate to small-molecule catalytic transformations or complex physiological processes, the structural features responsible for molecular association play into the well-known adage that form follows function where material property arises from the collective structural features of the molecular components. Because the form of chemical systems is derived from a complex blend of covalent and non-bonded contacts, codifying each contributor has become essential for …


Psi Performance, Belief In Psi, And Competition In A Game-Show Format, Heather L. Warner-Angel Jan 2017

Psi Performance, Belief In Psi, And Competition In A Game-Show Format, Heather L. Warner-Angel

Masters Theses

The current study was designed to explore variables influencing psi performance including gender, belief in psi, and competition between men and women. Features of the experiment involved a methodology using a visual image of the receivers, simple spatial location as targets, and monetary incentive to increase competition in a game-show type of environment. One of the goals of this study was to explore the role of competition between groups of senders and receivers as a facilitator of telepathic communication. Results of a one sample t-test comparing overall hit rate for the sample with expected probability were not significant, t(98)= …


Classification Of Basal Cell Carcinoma Using Telangiectatic Vessels And Machine Learning, Hemanth Yadav Aradhyula Jan 2017

Classification Of Basal Cell Carcinoma Using Telangiectatic Vessels And Machine Learning, Hemanth Yadav Aradhyula

Masters Theses

“Basal cell carcinoma (BCC) is one of the most common types of skin cancer in the United States. Early detection of BCC by noninvasive techniques can decrease delay in treatment and save cost. A recent study estimated that 5.4 million cases of non-melanocytic skin cancer (NMSC) occur each year in the US. BCC accounts for 50% of NMSC cases. Telangiectasia, which appears in most BCCs is an important feature for identification of BCC for an automatic diagnostic system. In this thesis, three methods for detection of telangiectasia present in dermoscopy lesion image (DI) were proposed. Detected telangiectasia in DI was …


Error Mapping Of Build Volume In Selective Laser Melting, Ninad Kulkarni Jan 2017

Error Mapping Of Build Volume In Selective Laser Melting, Ninad Kulkarni

Masters Theses

“Selective laser melting is one of the commonly used additive manufacturing processes employed for production of functional part. Therefore, quality aspects such as dimensional accuracy have become a point of great interest. Like all of the other additive manufacturing processes selective laser melting process suffers from the issue if having wide range of process parameters making the process control a complex task. Additionally, issues specific to the selective laser melting process such as position dependency of accuracy of the part, makes it difficult to predict the resulting dimensional inconsistencies in the part manufactured by this processes. This research is an …


Wrinkling Of Functionally Graded Sandwich Structures Subject To Biaxial And In-Plane Shear Loads, Harold Costa Jan 2017

Wrinkling Of Functionally Graded Sandwich Structures Subject To Biaxial And In-Plane Shear Loads, Harold Costa

Masters Theses

"Benefits of a functionally graded core increasing wrinkling stability of sandwich panels have been demonstrated in a recent paper [1] where a several-fold increase in the wrinkling stress was observed, without a significant weight penalty, using a stiffer core adjacent to the facings. In the present paper wrinkling is analyzed in case where the facings are subject to biaxial compression and/or in-plane shear loading and the core is arbitrary graded through-the-thickness. Two issues addressed are the effect of biaxial or in-plane shear loads on wrinkling stability of panels with both graded and ungraded core and the verification that functional grading …


Biodegradable Capacitive Pressure Sensor Toward Temporary Implants For Intervertebral Pressure Monitoring, Devdatt Chattopadhyay Jan 2017

Biodegradable Capacitive Pressure Sensor Toward Temporary Implants For Intervertebral Pressure Monitoring, Devdatt Chattopadhyay

Masters Theses

"The objective of this thesis is to demonstrate a new class of implantable biomedical device, based on biodegradable borate glass as the substrate material that can be potentially used to monitor the intervertebral pressure in the lumbar region of the human body. Two major types of implantable biomedical devices include the permanent prosthetic devices such as pacemakers and the temporary implants for short-term intervention and monitoring. Unless surgically removed after their intended operation, the temporary implants are left inside the body causing electromagnetic issues, latent complications and various biomechanical safety concerns. In order to address this issue, a new device …


Assessment Of Rockfall Rollout Risk Along Varying Slope Geometries Using The Rocfall And Crsp Software, Mariam S. Al E'Bayat Jan 2017

Assessment Of Rockfall Rollout Risk Along Varying Slope Geometries Using The Rocfall And Crsp Software, Mariam S. Al E'Bayat

Masters Theses

"Most routes in mountainous areas suffer from rock falling, rolling and bouncing risk. There are many computer programs concerned with simulating the rockfall problem, and whereas they have the same purpose, they however differ in the input data that's needed to simulate the problem, and they also differ in the way of processing and kind of output.

This study used Rocfall® and the Colorado Rockfall Simulation Program (CRSP®) to simulate sixty-three models of varying slope geometry, where only the slope geometry is changed with the same material properties for both the slope and the rocks.

Both programs were fast and …


Evaluation Of Preformed Particle Gels Penetration And Propagation Behavior For A Conformance Control Treatment In Partially Open Conduits, Ahmed Mohamed Aldalfag Jan 2017

Evaluation Of Preformed Particle Gels Penetration And Propagation Behavior For A Conformance Control Treatment In Partially Open Conduits, Ahmed Mohamed Aldalfag

Masters Theses

"Preformed particle gels (PPGs) serve as a conformance control agent and have been used widely to control excess water production through conduits, fractures or fracture-like features. This research ranks the parameters that impact PPG resistance to water flow in partially opened conduits. Experiments were conducted to examine the effect of brine concentration, PPG injection pressure, back pressure, reducing water salinity and matrix permeability on PPG resistance to water flow through conduits, PPG penetration to the matrix. PPGs were swelled in different concentration brines and were injected into the conduits at a few designed injection pressures. PPG swollen in high brine …


Determination Of Significant Parameters That Drive Fracture Optimization In The Glauconite Formation, Southern Chile, Ghassan Saleh Mahdi Alqatrani Jan 2017

Determination Of Significant Parameters That Drive Fracture Optimization In The Glauconite Formation, Southern Chile, Ghassan Saleh Mahdi Alqatrani

Masters Theses

"The Glauconite Formation in the Magallanes Basin of Southern Chile is a clay- and silica-rich formation with low permeability. As with many of the unconventional resources, the Glauconite Formation requires a hydraulic fracturing operation to enhance the productivity of the wells in this area.

Data and pertinent information of fracturing, completion, and reservoir quality parameters along with post-fracture production data were collected to initiate a database of nearly 70 wells, to be used to develop a better understanding of the fracturing behavior, optimize the well stimulation, and overcome the major barriers in the hydraulic fracturing of the Glauconite Formation. The …


Deformation Processes At The Leading Edge Of The Sevier Fold And Thrust Belt, Southwest Utah, William Joseph Michael Chandonia Jan 2017

Deformation Processes At The Leading Edge Of The Sevier Fold And Thrust Belt, Southwest Utah, William Joseph Michael Chandonia

Masters Theses

"Deformation processes leading to formation and abandonment of 'triangle zones' along the leading edge of the Sevier fold and thrust belt are investigated near Kanarraville, Utah through construction of a detailed geologic map and cross-section along Spring Creek. Here the eastern limb of the Kanarra fold, a Sevier structure, is well exposed along the Hurricane Cliffs due to uplift and erosion of the footwall of the Hurricane Fault. The east-verging Kanarra fold changes from upright to overturned within Spring Creek. Within the fold limb, parasitic folds, minor thrust faults, and duplex structures result in local tectonic overthickening of units and …


Structural And U-Pb Detrital Zircon Geochronologic Constraints On The Origin Of The Condrey Mountain Schist, California - Oregon, Joseph Reid Coons Jan 2017

Structural And U-Pb Detrital Zircon Geochronologic Constraints On The Origin Of The Condrey Mountain Schist, California - Oregon, Joseph Reid Coons

Masters Theses

"The Condrey Mountain Schist (CMS) of the Klamath Mountains (northern California and southern Oregon) represent low grade oceanic and terrigenous sediments thrust beneath higher grade ophiolitic rocks of the Rattlesnake Creek Terrane (RCT). This study presents new U-Pb detrital zircon dates from the CMS, and from the possibly correlative basin rocks of the Galice Formation and accretionary rocks of the South Fork Mountain Schist. The Galice Formation yields a maximum depositional age of ca. 152 Ma with prominent date distributions of ca. 150-200 Ma (39% of analyzed grains), 200-600 Ma (1%), 600 - 1000 Ma (2%), and 1000-3200 Ma (58%). …


Design And Analysis Of A Passive Heat Removal System For A Small Modular Reactor Using Star Ccm+, Raymond Michael Fanning Jan 2017

Design And Analysis Of A Passive Heat Removal System For A Small Modular Reactor Using Star Ccm+, Raymond Michael Fanning

Masters Theses

"Next generation nuclear power plants, specifically small modular reactor designs, are the best alternative to fossil fuels for power generation due to their power density and low carbon emissions and constant awareness of safety concerns. A promising safety feature of new designs is the removal of heat by passive systems in accident scenarios. The passive systems require no moving parts and no intervention by personnel. These systems must be accurately simulated for better understanding of the heat transport phenomena: natural convection cooling. Due to the fact that most work developing these passive heat removal systems are proprietary information, a passive …