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Emi Design Of Flyover Qsfp (Fqsfp) Connector For 56+ Gbps Applications, System Level Modelling Of The Z-Directed Component (Zdc), Pranay Kumar Vuppunutala Jan 2019

Emi Design Of Flyover Qsfp (Fqsfp) Connector For 56+ Gbps Applications, System Level Modelling Of The Z-Directed Component (Zdc), Pranay Kumar Vuppunutala

Masters Theses

"This thesis comprises of two parts. Firstly, the Flyover Quad Small Form Pluggable (FQSFP) approach for 56+ Gbps applications is introduced to overcome the limitations from a large loss on typical QSFP ports with surface mount to Printed Circuit Board (PCB) traces. By replacing the PCB traces to the twinax cables, it is possible to achieve around 7 dB lower insertion loss at 40 GHz for the 12-inch path from the switch IC to connector than that of PCB trace with a low loss substrate. Also, to investigate electromagnetic interference (EMI) aspect of FQSFP approach, a simulation model of FQSFP …


Gel Composition And Brine Concentration Effect On Hydrogel Dehydration Subjected To Uniaxial Compression, Xinrui Zhao Jan 2019

Gel Composition And Brine Concentration Effect On Hydrogel Dehydration Subjected To Uniaxial Compression, Xinrui Zhao

Masters Theses

"Gel treatment is a process that injects the gel into a reservoir to control the conformance and improve the sweep efficiency of injection fluids. At a certain pressure gradient, the gel dehydrates in a reservoir due to mechanical forces. This work evaluates the effects of the gel composition and brine concentration on gel dehydration under uniaxial compression. A sodium acrylate-co-acrylamide based gel cross-linked with N, N'-Methylenebisacrylamide (MBAA) was used for the study. The compression test is performed with a rheometer with a plate-plate geometry. The gel dehydration under pressure was measured to see how gel dehydration would be impacted by …


Breaker Evaluation And Formation Damage Remediation Of Re-Crosslinkable Preformed Particle Gel (Rppg), Enze Zhou Jan 2019

Breaker Evaluation And Formation Damage Remediation Of Re-Crosslinkable Preformed Particle Gel (Rppg), Enze Zhou

Masters Theses

"Re-crosslinkable preformed particle gel (RPPG) is a newly developed preformed particle gel for improving sweep efficiency and oil recovery by blocking or reducing the conductivity of fractures and fracture-like channels or conduits. However, RPPG has the potential to plug the facilities or damage the formation if a treatment is not properly conducted.

This work presents the performance of selected oxidizing breakers on the degradation of RPPG. The influence of a few factors on the degradation process was investigated, including breaker type, breaker concentration, temperature, gel concentration, gel aging time, and gel size. Results indicate that breaker type, concentration, and temperature …


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 …


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 …


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 …


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, …


Performance Investigation Of Surface Modified Ceramic Microfiltration Membranes And The Effects Of Ionic Strength, Choji Bitrus Daches Jan 2019

Performance Investigation Of Surface Modified Ceramic Microfiltration Membranes And The Effects Of Ionic Strength, Choji Bitrus Daches

Masters Theses

"The performance of ceramic membranes surface coated with cysteic acid to improve efficiency and reduce fouling rate was studied under two transmembrane pressure (TMP) and constant crossflow velocity (CFV). The filtration process was done in crossflow mode to allow for extended operation of the membranes. the performance of the membranes were determined in terms of the measured fluxes and on content rejection. Cleaning-in-place (CIP) was done on the membranes to ensure flux recovery after each run. The results showed significant improvement on the performance of the membranes with respect to high permeate fluxes and high oil content rejection (> 99.5%). …


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 …


Practical Methods For Source Separation In Emc Measurements, Yuanzhuo Liu Jan 2019

Practical Methods For Source Separation In Emc Measurements, Yuanzhuo Liu

Masters Theses

"Electromagnetic emission is critical in the electronic industry with the rapid growth of the development of the electronic device. To identify the emission from the multipule sources, two methods are proposed in the near field scan and total radiated power measurement respectively.

The first method can be applied in the measurement of the field generated by multiple non-correlated sources. The contribution of each source is determined using a blind source separation (BSS) technique. The measurements are performed using one scanning probe and stationary reference probes, avoiding the need to measure the spatial correlations of the random field. The resolving result …


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 …


Review And Data Analysis Of Low Salinity Water Effect Through Induced Fine Migration, Dawei Xu Jan 2019

Review And Data Analysis Of Low Salinity Water Effect Through Induced Fine Migration, Dawei Xu

Masters Theses

"Low salinity water flooding (LSWF) is well proved to be an effective EOR technology both in laboratory and field tests, however, the conditions for LSWF to work and EOR mechanism is still debatable. Up till now, many mechanisms have been proposed to explain the incremental oil recovery in sandstone by LSWF, for instance, fine migration, ionic exchange, wettability alteration and pH increase.

In this study, we only focus on low salinity water flooding effect through induced fine migration mechanism. The objective of this study is to conduct a comprehensive analysis using statistical analysis methods and explaining the mechanism of fine …


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 …


Performance Evaluation Of Bmi Resin System For Thin-Ply Composites, Manoj Kumar Reddy Rangapuram Jan 2019

Performance Evaluation Of Bmi Resin System For Thin-Ply Composites, Manoj Kumar Reddy Rangapuram

Masters Theses

"Composites materials are increasingly being used in aerospace applications over the past few years. The unique properties like high strength to weight ratio, thermal stability, fatigue and corrosion resistance set them apart from the conventional materials. Composite materials are well suited for the applications where weight is the primary concern in the design. Composites structures are vulnerable to mechanical as well as thermal loadings. Transverse micro-cracking and delamination are the most common type of failures in composite materials. The thickness of the ply being used play a key role dictating the properties of the resultant composite structure. As the ply …


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 …


Aerosol-Jet Printing And Flash Sintering Of Conformal Conductors On Non-Planar Surfaces, I-Meng Chen Jan 2019

Aerosol-Jet Printing And Flash Sintering Of Conformal Conductors On Non-Planar Surfaces, I-Meng Chen

Masters Theses

”The printed electronics have been broadly applied in our daily lives, many new manufacturing methodologies are studied and investigated. The research here presented the full manufacturing process of printed conductors of aerosol printing and flash sintering techniques on substrates such as planar and non-planar surfaces.

The aerosol printing (AJP) was introduced because of its simplicity in experimental setup and flexibility of printing. It produces less ink waste and consumes less manufacturing cost. Furthermore, it has the direct-write ability to print in any customized patterns or shapes on non-planar surfaces. In this study, the Cu NPs was selected as the functioning …


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 …


Influence Of Pumping Parameters On The Freeze-Thaw And Scaling Resistance Of Highly Workable Concrete, Alexandra Nicole Wehar Jan 2019

Influence Of Pumping Parameters On The Freeze-Thaw And Scaling Resistance Of Highly Workable Concrete, Alexandra Nicole Wehar

Masters Theses

“Over the past 60 years, pumping concrete has gained popularity due to the economic and technical benefits that typically accompanies it. However, boom configuration and flow rate can adversely affect freeze-thaw and scaling resistance of concrete due to the effects of pressure on the air-void system. Therefore, the objective of this research is to assess the influence of different pumping parameters on the durability of hardened self-consolidating concrete. Self-consolidating, flowable, and conventional concrete mixtures were tested during large scale pumping experiments positioning the pump boom in an “A” and a flat shape as well as using different pumping speeds. In …


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, …


Mightier Than The Sword: Benjamin Franklin’S Satirical Rebuke Of British Policy, Bethany L. Fontenot-Miller Jan 2019

Mightier Than The Sword: Benjamin Franklin’S Satirical Rebuke Of British Policy, Bethany L. Fontenot-Miller

Masters Theses

The genius of Benjamin Franklin resides not in his unique personality or worldly manner but in his distinct ability to eloquently express his ideas in written form. One of his most notable and peculiar scripted expressions emanated from his desire to assert American authority in peace negotiations with Great Britain in the final stages of the American Revolution. Franklin’s “Supplement” to the Boston Independent Chronicle, printed in 1782 at his press at Passy, satirized British political and economic procedure in an effort to illuminate British hypocrisy and defend American interests in the peace process. Though the “Supplement” has only recently …


Analyzing The Effects Of Attitude Errors When Quantifying The On-Orbit Performance Of A Cubesat Micropropulsion System, Andrew Orion Watson Jan 2019

Analyzing The Effects Of Attitude Errors When Quantifying The On-Orbit Performance Of A Cubesat Micropropulsion System, Andrew Orion Watson

Masters Theses

"CubeSats and small satellites have become popular methods of performing space research. Accordingly, interest has also grown in designing micropropulsion systems to increase the lifespan of these satellites. This work describes the framework for analyzing the effects of imperfect attitude determination and control when quantifying the on-orbit performance of a micropropulsion system. The Gauss variation of parameters equations were implemented to model the orbital mechanics, with perturbing models for the zonal harmonics, atmospheric drag, and solar radiation pressure included. Two common sources for imperfections in a spacecraft's attitude were considered. The first was to consider the effect of the spacecraft …


Light Touch Based Virtual Cane For Balance Assistance During Standing, Sindhu Reddy Alluri Jan 2019

Light Touch Based Virtual Cane For Balance Assistance During Standing, Sindhu Reddy Alluri

Masters Theses

"Can additional information about one's body kinematics provided through hands improve human balance? Light-Touch (LT) through hands helps improve balance in a wide range of populations, both healthy and impaired. The force is too small to provide any meaningful mechanical assistance -- rather, it is suggested that the additional sensory information through hands helps the body improve balance.

To investigate the potential for improving human balance through biofeedback through hands, we developed a Virtual Cane (VC) for balance assistance during standing. The VC mimics the physical cane's function of providing information about one's body in space. Balance experiments on 10 …


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 …


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 …


A Genome Wide Survey Of The Insertion Sequences In Halanaerobium Hydrogeniformans, A Haloalkaliphilic Anaerobic Bacterium, Kody Austin Bassett Jan 2019

A Genome Wide Survey Of The Insertion Sequences In Halanaerobium Hydrogeniformans, A Haloalkaliphilic Anaerobic Bacterium, Kody Austin Bassett

Masters Theses

"Insertion sequences (IS) are the smallest prokaryotic transposable elements. These mobile genes are highly diverse in size and structure, making them difficult to study. The transposition activity of insertion sequences has a significant role in evolution by enabling genomic plasticity via genome rearrangements. Insertion sequences are largely uncharacterized and thus methods to improve the ability to accurately identify, annotate, and infer genomic impact of insertion sequences is limited. A sequential set of methods using readily available genomic and bioinformatic tools was developed to accurately identify insertion sequences. This method was used to perform an entire genome survey of Halanaerobium hydrogeniformans …


High-Speed Pcb Trace Design Using A Behavioral Surface Roughness Model And High-Speed Test Coupon Design With Non-Functional Pads, Han Gao Jan 2019

High-Speed Pcb Trace Design Using A Behavioral Surface Roughness Model And High-Speed Test Coupon Design With Non-Functional Pads, Han Gao

Masters Theses

"In high-speed digital systems as data rates increase to tens of gigabits per second, the loss from the conductor surface roughness cannot be ignored. Djordjeic and Huray roughness model is widely used to count for the conductor roughness loss. However the practical application of the existed models are not straight forward since the frequency-dependent dielectric loss is usually unknown, leading to high discrepancies at high frequencies (above 10 GHz). To solve this problem, a behavioral model was developed by adding a dispersive term to the dielectric. The dispersive term in the model captures dispersion behavior observed in the measurement accurately. …


Diffusion Kinetics In Promising Adsorbents For Gas Capture Processes, Teresa Gelles Jan 2019

Diffusion Kinetics In Promising Adsorbents For Gas Capture Processes, Teresa Gelles

Masters Theses

"This reports the results of experimental studies aimed at characterizing the transport properties of promising adsorbents for various gas capture processes by the "zero length column" (ZLC) technique. ZLC was used to measure the intracrystalline diffusivities of single and binary components of ethane and ethylene in powder and pellet samples of paraffin-selective adsorbents Ni(bdc)(ted)0.5 (Ni-BT) and ZIF-7 for the purpose of olefin/paraffin separation. Results show that binary gaseous systems result in intracrystalline diffusion time constants slightly lower than those in single component gaseous streams due to coadsorption effects. It was also found that ethylene diffusion was affected by surface …


Amplitude-Preserved Processing Of The Blackfoot 10 Hz Seismic Data, Bader Mohammed A Algarni Jan 2019

Amplitude-Preserved Processing Of The Blackfoot 10 Hz Seismic Data, Bader Mohammed A Algarni

Masters Theses

"The broadband 3C-2D seismic survey was acquired in the Blackfoot Field in southern Alberta. The single-component 10 Hz geophone data were reprocessed to increase vertical resolution and provide a better seismic image of the incised valley channel fill deposits in the Glauconitic Formation. The amplitude-preserved seismic processing of the data was followed by the Kirchhoff prestack time migration. The processing parameters and algorithms used were based on parameter optimization approach. Elevation statics and surface consistent residual statics were utilized to remove near surface delays in the data. Seismic noise, such as ground roll and air blast, were attenuated effectively by …


Effects Of Uncertainty Refinement On Satellite Collision Probability, Bruce Thomas Morrison Jan 2019

Effects Of Uncertainty Refinement On Satellite Collision Probability, Bruce Thomas Morrison

Masters Theses

"Due to the drastic increase in orbital debris about the Earth, the likelihood for new and current mission satellites to collide with other objects grows. When a mission satellite is placed in a highly populated orbit in the vicinity of other satellites or debris, it is necessary to consider the probability of collision to assess any possible conjunctions. The computation of the collision probability is heavily dependent on the relative position and velocity of the objects during conjunction, as well as the combined covariance. There are two main types of analytic collision probability computations; the first assumes that the objects …