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Asphaltene Stability In Crude Oil During Carbon Dioxide Injection And Its Impact On Oil Recovery: A Review, Data Analysis, And Experimental Study, Sherif M. Fakher Jan 2019

Asphaltene Stability In Crude Oil During Carbon Dioxide Injection And Its Impact On Oil Recovery: A Review, Data Analysis, And Experimental Study, Sherif M. Fakher

Masters Theses

"Crude oils are usually associated with many compounds, some of which are favorable and others, which are not. One of the most unfavorable components of crude oil that pose severe operational problems and decreases oil production significantly are asphaltenes. These compounds are solids that are homogenized in the crude oil at room temperature but tend to separate from solution when agitated. They can deposit in the reservoir pores, wellbore, and transportation pipelines thus causing severe operational problems and oil recovery reduction.

Even though researchers have been studying asphaltenes for more than 100 years, there is still an ambiguity concerning asphaltene …


Archaeological Investigation Using Geophysical Methods To Locate Historic Byram's Ford Road, Marshall Seth Foster Jan 2019

Archaeological Investigation Using Geophysical Methods To Locate Historic Byram's Ford Road, Marshall Seth Foster

Masters Theses

"Ground penetrating radar, a time domain electromagnetic metal detector and a frequency domain electromagnetic metal detector were used with the goal of locating a section of the Byram's Ford Road believed to be intersecting the historic Big Blue Battlefield in the Westport area of Kansas City, Missouri.

Ground penetrating data were acquired at three sites, Site A, Site B, and Site C. The time domain EM metal detector was used to acquire data at Site A, where subsequent ground truthing was conducted using the frequency domain EM metal detector and an excavation tool. Significant anomalies were visible on both the …


Routing Algorithm For The Ground Team In Transmission Line Inspection Using Unmanned Aerial Vehicle, Yu Li Jan 2019

Routing Algorithm For The Ground Team In Transmission Line Inspection Using Unmanned Aerial Vehicle, Yu Li

Masters Theses

"With the rapid development of robotics technology, robots are increasingly used to conduct various tasks by utility companies. An unmanned aerial vehicle (UAV) is an efficient robot that can be used to inspect high-voltage transmission lines. UAVs need to stay within a data transmission range from the ground station and periodically land to replace the battery in order to ensure that the power system can support its operation. A routing algorithm must be used in order to guide the motion and deployment of the ground station while using UAV in transmission line inspection. Most existing routing algorithms are dedicated to …


Evolved Parameterized Selection For Evolutionary Algorithms, Samuel Nathan Richter Jan 2019

Evolved Parameterized Selection For Evolutionary Algorithms, Samuel Nathan Richter

Masters Theses

"Selection functions enable Evolutionary Algorithms (EAs) to apply selection pressure to a population of individuals, by regulating the probability that an individual's genes survive, typically based on fitness. Various conventional fitness based selection functions exist, each providing a unique method of selecting individuals based on their fitness, fitness ranking within the population, and/or various other factors. However, the full space of selection algorithms is only limited by max algorithm size, and each possible selection algorithm is optimal for some EA configuration applied to a particular problem class. Therefore, improved performance is likely to be obtained by tuning an EA's selection …


Impact Of Framing And Base Size Of Computer Security Risk Information On User Behavior, Xinhui Zhan Jan 2019

Impact Of Framing And Base Size Of Computer Security Risk Information On User Behavior, Xinhui Zhan

Masters Theses

"This research examines the impact of framing and base size of computer security risk information on users' risk perceptions and behavior (i.e., download intention and download decision). It also examines individual differences (i.e., demographic factors, computer security awareness, Internet structural assurance, self-efficacy, and general risk-taking tendencies) associated with users' computer security risk perceptions. This research draws on Prospect Theory, which is a theory in behavioral economics that addresses risky decision-making, to generate hypotheses related to users' decision-making in the computer security context. A 2 x 3 mixed factorial experimental design (N = 178) was conducted to assess the effect of …


Advanced Techniques For Improving Canonical Genetic Programming, Adam Tyler Harter Jan 2019

Advanced Techniques For Improving Canonical Genetic Programming, Adam Tyler Harter

Masters Theses

"Genetic Programming (GP) is a type of Evolutionary Algorithm (EA) commonly employed for automated program generation and model identification. Despite this, GP, as most forms of EA's, is plagued by long evaluation times, and is thus generally reserved for highly complex problems. Two major impacting factors for the runtime are the heterogeneous evaluation time for the individuals and the choice of algorithmic primitives. The first paper in this thesis utilizes Asynchronous Parallel Evolutionary Algorithms (APEA) for reducing the runtime by eliminating the need to wait for an entire generation to be evaluated before continuing the search. APEA is applied to …


Less Is More: Beating The Market With Recurrent Reinforcement Learning, Louis Kurt Bernhard Steinmeister Jan 2019

Less Is More: Beating The Market With Recurrent Reinforcement Learning, Louis Kurt Bernhard Steinmeister

Masters Theses

"Multiple recurrent reinforcement learners were implemented to make trading decisions based on real and freely available macro-economic data. The learning algorithm and different reinforcement functions (the Differential Sharpe Ratio, Differential Downside Deviation Ratio and Returns) were revised and the performances were compared while transaction costs were taken into account. (This is important for practical implementations even though many publications ignore this consideration.) It was assumed that the traders make long-short decisions in the S&P500 with complementary 3-month treasury bill investments. Leveraged positions in the S&P500 were disallowed. Notably, the Differential Sharpe Ratio and the Differential Downside Deviation Ratio are risk …


Propagation Of Uncertainty Through Coning, Sculling, And Scrolling Corrections For Inertial Navigation, James Daniel Alan Brouk Jan 2019

Propagation Of Uncertainty Through Coning, Sculling, And Scrolling Corrections For Inertial Navigation, James Daniel Alan Brouk

Masters Theses

"This thesis investigates the propagation of estimation errors through generalized coning, sculling, and scrolling algorithms used in modern day inertial navigation systems, in order to accurately quantify the uncertainty in the estimation of position, velocity, and attitude. The corrections for coning, sculling, and scrolling algorithms have an often unaccounted for effect on documented and empirically derived error statistics for measurements used to predict the uncertainty in a vehicle's position, velocity, and attitude estimates. Through the development of an error analysis for these generalized algorithms, mappings of the measurement and estimation errors through the correction termare generated. Using the developed mappings, …


Geophysical Imaging Beneath Lake Chesterfield, Missouri, James Daniell Hayes Jan 2019

Geophysical Imaging Beneath Lake Chesterfield, Missouri, James Daniell Hayes

Masters Theses

"Lake Chesterfield in Wildwood, Missouri, has been leaking since construction of the earth-fill dam was completed in 1986, despite numerous mitigation efforts. The mitigation efforts, including the injection of grouting and the emplacement of clay liners, has not solve the leakage problem.

In the current study, geophysical (subsurface imaging) data was acquired across the drained and dry lake bed and along the base of the earth-fill dam to 1) map variable depth to top of bedrock, 2) determine the variable quality of the bedrock to depths on the order of 80 ft., 3) identify any significant karst features beneath the …


Design And Implementation Of Applications Over Delay Tolerant Networks For Disaster And Battlefield Environment, Karthikeyan Sachidanandam Jan 2019

Design And Implementation Of Applications Over Delay Tolerant Networks For Disaster And Battlefield Environment, Karthikeyan Sachidanandam

Masters Theses

"In disaster/battlefield applications, there may not be any centralized network that provides a mechanism for different nodes to connect with each other to share important data. In such cases, we can take advantage of an opportunistic network involving a substantial number of mobile devices that can communicate with each other using Bluetooth and Google Nearby Connections API(it uses Bluetooth, Bluetooth Low Energy (BLE), and Wi-Fi hotspots) when they are close to each other. These devices referred to as nodes form a Delay Tolerant Network (DTN), also known as an opportunistic network. As suggested by its name, DTN can tolerate delays …


Multiphysics Prediction Model Of Microwave Curing For Thick Polymer Composites, Siva Dasari Jan 2019

Multiphysics Prediction Model Of Microwave Curing For Thick Polymer Composites, Siva Dasari

Masters Theses

"Microwave curing technologies have many advantages over the traditional thermal curing methods for the manufacturing of fiber reinforced polymers, especially the processing speed and energy efficiency. Energy can be instantaneously transferred through applied electromagnetic fields and heat is generated based on dipolar rotational interactions. Microwave curing processes have been used for glass fiber composites but there are significant challenges associated with microwave curing of carbon fiber composites. Efficient heating may be difficult due to high dielectric loss associated with carbon fibers. Laminate quality will be highly dependent on the uniformity of the electromagnetic field in the material. In this work, …


U-Pb Detrital Zircon Geochronology Of Paleozoic Clastics Of The Ozark Plateau: Implication For Sea-Level Fluctuations And Far-Field Tectonics, Chen Zhao Jan 2019

U-Pb Detrital Zircon Geochronology Of Paleozoic Clastics Of The Ozark Plateau: Implication For Sea-Level Fluctuations And Far-Field Tectonics, Chen Zhao

Masters Theses

"The Ozark Plateau of south-central Missouri is underlain by Ordovician to Pennsylvanian carbonate and clastic strata. Enigmatic, presumably Pennsylvanian 'filled sink' structures are common on the Ozark Plateau and remain a source of controversy. We present results for U-Pb ages of detrital zircons for 13 samples from the OP. We use U-Pb ages from other Paleozoic clastics and 'filled sinks' on the OP, to suggest: 1) FSS record a period of Middle Ordovician erosion and sedimentation and 2) document significant shifts in sediment provenance that reflect regional tectonic events affecting the North American Craton.

The KDE plots of normalized detrital …


The Correlation Between Sleep And Lifespan In Drosophila Melanogaster, Joshua Randall Lisse Jan 2019

The Correlation Between Sleep And Lifespan In Drosophila Melanogaster, Joshua Randall Lisse

Masters Theses

”Adequate sleep is associated with an individual’s health. Too little sleep is associated with many health problems, including cardiovascular disease, obesity, and a general increase in all-cause mortality. Yet the molecular changes that link poor sleep and changes in health are still not well understood. Individuals have a unique daily need for sleep, and deviations from the animal’s regular sleeping patterns can be indicative of, or result in, underlying changes in its health. Therefore, we hypothesize that changes in the sleep architecture in Drosophila melanogaster reflect changes in the fly’s health.

We determined sleep architecture in wild-type male flies over …


Estimating Electromagnetic Emissions From A Site Installation With Multiple Racks Of Server Equipment, Ze Sun Jan 2019

Estimating Electromagnetic Emissions From A Site Installation With Multiple Racks Of Server Equipment, Ze Sun

Masters Theses

“There are hundreds, sometimes even thousands, of servers working simultaneously inside a data center. Their radiation can be a problem and cause EMI issues. However, it is not feasible to perform full-wave simulation of these racks because of the large electric size of the model. In this thesis, an algorithm is proposed to predict the emission form rack array. The equivalent dipole source is extracted from EMI measurement data of a single rack and used as the radiation source in the multiple rack model. The coupling between racks cannot be ignored, but through the simulation, it is also found that …


Removal Of Antimony And Bismuth From Copper Electrorefining Electrolyte By Two Proprietary Solvent Extraction Extractants, Andrew Artzer Jan 2019

Removal Of Antimony And Bismuth From Copper Electrorefining Electrolyte By Two Proprietary Solvent Extraction Extractants, Andrew Artzer

Masters Theses

"Antimony and bismuth are two of the most problematic impurities in copper electrorefining (ER). Because of this, much research has been done investigating the ways to remove them. Processes that are currently being used industrially include anode additions, liberators, ion exchange (IX), and solvent extraction (SX). Of these, liberators and anode additions are the most common while SX is the least, mostly being used for arsenic removal. There are other methods that have been evaluated, but are not in commercial use. These include the use of various electrolyte additives, and adsorbents such as bentonite clay and heavy metal sulfates.

Two …


Evaluation Of Naturally Occurring And Anthropogenic Contamination In Missouri Streams, Christina Jane Sehrt Jan 2019

Evaluation Of Naturally Occurring And Anthropogenic Contamination In Missouri Streams, Christina Jane Sehrt

Masters Theses

"The goal of this study is to observe the values and variability of water quality parameters and benthic macroinvertebrates in watersheds with very little anthropogenic impact and to compare these values with those acquired in watersheds with more anthropogenic impact. The following five HUC 12-digit watersheds had very little anthropogenic impact and were considered "pristine": Rogers Creek, Mill Creek, Middle West Fork-Black River, Bee Fork, and Ottery Creek. Five largely urban sub-basins were also considered; these basins are: Grand Glaize Creek, Glaize Creek, Sugar Creek, Hominy Creek, and Grindstone Creek. For each watershed, both water quality parameters and benthic macroinvertebrates …


Coupling Path Visualization Based On Reciprocity Theorem, Yang Zhong Jan 2019

Coupling Path Visualization Based On Reciprocity Theorem, Yang Zhong

Masters Theses

"A new method to visualize coupling path is proposed to help solve EMI problems. Based on the reciprocity theorem and the concept of reaction, coupling coefficient (CC) is defined to characterize coupling power density. For two-port networks, surface integral of CC can represent coupled voltage on the open-circuited port or coupled power on the loaded port. For dipole-moment based systems, surface integral of CC can represent coupled field components. The calculated CC should be a complex scalar at each point. By properly adjusting the excitation phases, the imaginary part of surface integral of CC will be zero and thus can …


Passively-Coded Embedded Microwave Sensors For Materials Characterization And Structural Health Monitoring (Shm), Katelyn Rose Brinker Jan 2019

Passively-Coded Embedded Microwave Sensors For Materials Characterization And Structural Health Monitoring (Shm), Katelyn Rose Brinker

Masters Theses

"Monitoring and maintaining civil, space, and aerospace infrastructure is an ongoing critical problem facing our nation. As new complex materials and structures, such as multilayer composites and inflatable habitats, become ubiquitous, performing inspection of their structural integrity becomes even more challenging. Thus, novel nondestructive testing (NDT) methods are needed. Chipless RFID is a relatively new technology that has the potential to address these needs. Chipless RFID tags have the advantage of being wireless and passive, meaning that they do not require a power source or an electronic chip. They can also be used in a variety of sensing applications including …


Characterization Of Chromosomal Translocations In A Group Of Killifish Species By Using Genome-Wide High-Density Snp Mapping Approach, Naznin Sultana Remex Jan 2019

Characterization Of Chromosomal Translocations In A Group Of Killifish Species By Using Genome-Wide High-Density Snp Mapping Approach, Naznin Sultana Remex

Masters Theses

"The role of chromosomal rearrangements in reproductive isolation and introgression between species is poorly understood. In heterozygous form, rearrangements may directly interrupt meiotic progression leading to partial sterility/subfertility (underdominance) or may suppress local meiotic segregation (recombination suppression). Such unbalanced meiotic segregation may also result in reproductive isolation and play roles as a driving force of speciation. The objective of this study was to gain insight into the pattern of chromosomal rearrangements in two closely related killifish species in the genus Fundulus (F. notatus, and F. olivaceus) by constructing genetic linkage maps using high-resolution single nucleotide polymorphism (SNP) …


The Effects Of Ambient Benevolent Sexism And Its Implications In The Workplace, Amanda E. Mosier Jan 2019

The Effects Of Ambient Benevolent Sexism And Its Implications In The Workplace, Amanda E. Mosier

Masters Theses

"The purpose of this study was to examine women's reactions to witnessing benevolent sexism (i.e., ambient benevolent sexism). Female participants (n = 59) witnessed another woman being treated with hostile sexism (HS), benevolent sexism (BS), or no sexism and their reactions were examined in respect to a) working memory capacity, b) task-specific self-efficacy, c) mental intrusions of incompetence, and d) negative affect. The study also examined how participants' personal endorsement of BS impacted the relationship between sexism condition and the outcome variables. Results indicate that there were no direct effects of sexism condition on the outcome variables, though there was …


Reprocessing And Comparison Of The 2 Hz And 10 Hz Vertical Component Seismic Data Of The Blackfoot 3c-2d Survey, Mete Sarikaya Jan 2019

Reprocessing And Comparison Of The 2 Hz And 10 Hz Vertical Component Seismic Data Of The Blackfoot 3c-2d Survey, Mete Sarikaya

Masters Theses

"The Blackfoot seismic 3C-2D data were obtained from the Consortium for Research in Elastic Wave Exploration Seismology (CREWES) Project in 1995. The seismic data acquisition was performed in the Blackfoot Field, which is around 15 km southeast of Strathmore, Alberta. The 4 Hz and 10 Hz vertical component data are reprocessed to increase the quality and resolution of the seismic images. The Glauconitic sand reservoir at approximately 1.1 s, and a strong reflection about at 1.5 s are the focuses of the study.

The processing procedure includes different parameters and methods to obtain the best seismic sections of 2 Hz …


Predictive Modeling Of Webpage Aesthetics, Ang Chen Jan 2019

Predictive Modeling Of Webpage Aesthetics, Ang Chen

Masters Theses

"Aesthetics plays a key role in web design. However, most websites have been developed based on designers' inspirations or preferences. While perceptions of aesthetics are intuitive abilities of humankind, the underlying principles for assessing aesthetics are not well understood. In recent years, machine learning methods have shown promising results in image aesthetic assessment. In this research, we used machine learning methods to study and explore the underlying principles of webpage aesthetics"--Abstract, page iii.


Temporal Changes Of Nutrients Within The Lower Grand River Watershed And Selected Sites, Weston Scott Duley Jan 2019

Temporal Changes Of Nutrients Within The Lower Grand River Watershed And Selected Sites, Weston Scott Duley

Masters Theses

"This report presents the results of a study carried out in collaboration with the U.S. Geological Survey (USGS) and the Missouri Department of Natural Resources (MDNR) to estimate total nitrogen (TN) and total phosphorus (TP) at five USGS monitoring sites within Lower Grand River Watershed (LGRW) and two monitoring sites on the Missouri River. The objective of this study was to quantify temporal changes in TN and TP concentrations and compare those to best management practices (BMPs).

In this study, the approach to the analysis of long-term surface water-quality data by using Weighted Regressions on Time, Discharge and Seasons models …


Characterization Of The Surface Condition In Aa6061 Resulting From Deep Rolling As A Function Of Common Industrial Parameters, Andrew Kenneth Layer Jan 2019

Characterization Of The Surface Condition In Aa6061 Resulting From Deep Rolling As A Function Of Common Industrial Parameters, Andrew Kenneth Layer

Masters Theses

"Roller burnishing is widely used in industry to improve the surface finish and fatigue life of components. As weight reduction continues to grow in the automotive and transportation industries, deep rolling can help maintain product performance by mitigating the increase in component stresses resulting from lower weight systems. Deep rolling parameters such as tool, applied angle, feed rate, spindle speeds, and relative tool direction all affect cycle time, product performance, and appearance. The effects of common industrial parameters on the resultant surface roughness and residual stress profiles were studied in this investigation. The samples were manufactured on a CNC lathe …


Changes In Fresh Properties Of Flowable Concrete Induced By Pumping And Composition Of The Lubrication Layer, Alexis Salinas Jan 2019

Changes In Fresh Properties Of Flowable Concrete Induced By Pumping And Composition Of The Lubrication Layer, Alexis Salinas

Masters Theses

"Pumping is an easy method to move concrete while keeping stability. It is worldwide accepted as one of the principal methods for concrete placement, as it accelerates construction. Typically, concrete acceptance in terms of fresh quantitative empirical properties (i.e. slump/slump flow and air content) are performed prior to the pumping process. However, empirical measurements have the drawback that they only measure 1 point. Rheology is better tool to evaluate the behavior of concrete. Pumping is a process that induces considerable shearing in the concrete that can impact its rheological properties. Therefore, the magnitude of these changes in fresh properties depends …


Projectile Impact Effects On A 50 Psi Plug Type Coal Mine Seal, Bruce Albert Von Niederhäusern Jan 2019

Projectile Impact Effects On A 50 Psi Plug Type Coal Mine Seal, Bruce Albert Von Niederhäusern

Masters Theses

"The current lack of projectile damage criteria for mine seals is assessed to determine if criteria should be developed. Impact experiments were performed on a full-scale 50 psi mine seal to determine failure modes, dynamic stress state, and assess risk to existing operational mine seals. Test projectiles were selected from common underground coal mine items propelled by means of a black powder projectile generator. Projectile velocities attained in testing ranged from approximately 100 to 650 ft/s (30 to 200 m/s). Dynamic strain was measured on the non-impact face to derive the state of stress and estimate failure criteria. Penetration models …


The Impact Of Artificial Intelligence On Higher Education, Yizhi Ma Jan 2019

The Impact Of Artificial Intelligence On Higher Education, Yizhi Ma

Masters Theses

"A perfect storm is hitting higher education. Decreased funding from traditional funding sources, such as State Governments, and transformative changes caused by artificial intelligence (AI) will revolutionize higher education. Higher education needs to change and evolve quickly and continuously to prepare students for the upheavals in the job market caused by AI, machine learning, and automation.

As AI continues to make inroads into our world and our lives, its impact and effects can no longer be ignored. What kinds of organizational changes in higher education are necessary? How can higher education continue to prepare students for the AI evolution and …


Development Of Castrip Dual Phase Steel, Brenton Allen Hrebec Jan 2019

Development Of Castrip Dual Phase Steel, Brenton Allen Hrebec

Masters Theses

“Thermomechanical processing necessary to produce DP 980 steel using CASTRIP hot band was investigated. The resultant steel has an ultimate tensile strength of 1038 MPa, yield strength of 744 MPa, and total elongation of 8.6%. These mechanical properties were achieved by batch annealing the hot band at 649°C for 48 hours and cold rolling to a 20% reduction. The steel was continuously annealed to simulate a galvanization cycle with an intercritical temperature of 810°C. The possibility of improving the texture of the steel by warm rolling under dynamic strain aging conditions was investigated. Dynamic strain aging in the CASTRIP hot …


Controlled Switching In Kalman Filtering And Iterative Learning Controls, He Li Jan 2019

Controlled Switching In Kalman Filtering And Iterative Learning Controls, He Li

Masters Theses

“Switching is not an uncommon phenomenon in practical systems and processes, for examples, power switches opening and closing, transmissions lifting from low gear to high gear, and air planes crossing different layers in air. Switching can be a disaster to a system since frequent switching between two asymptotically stable subsystems may result in unstable dynamics. On the contrary, switching can be a benefit to a system since controlled switching is sometimes imposed by the designers to achieve desired performance. This encourages the study of system dynamics and performance when undesired switching occurs or controlled switching is imposed. In this research, …


Inclusion Engineering In Femnal Steels, Rairu Vaz Penna Jan 2019

Inclusion Engineering In Femnal Steels, Rairu Vaz Penna

Masters Theses

"Low density high Mn and Al steels, or FeMnAl steels, show great promise for military vehicles and automotive applications in which high strength and toughness is a requirement. However, these steels are subject to processing challenges including development of oxide and nitride inclusions during melting and casting as well as a large as-cast grain size and heavy interdendritic segregation. This can lead to non-uniform heat treatment response and cracking during subsequent hot rolling. Adding up to 10%Al lowers the density of these steels by as much as 15%, unfortunately, this also results in large amounts of hard and faceted AlN …