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Masters Theses

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Particle Mediated Enhanced Mass Transfer Of Diethylhexyl Phthalate: A Pilot Scale System Design, Melissa Buechlein Jan 2016

Particle Mediated Enhanced Mass Transfer Of Diethylhexyl Phthalate: A Pilot Scale System Design, Melissa Buechlein

Masters Theses

"Phthalates are a class of SVOCs that are widely used as plasticizers and recently epidemiological and toxicological research has found a link between phthalate exposure and increased occurrences of adverse health effects. SVOCs can potentially partition into household dust and airborne particles. Models and micro chamber studies have identified that airborne particles effectively increase SVOC deposition to or emissions from surfaces; SVOCs partition to aerosols in the bulk air, the aerosols then migrate to the surfaces due to eddy and Brownian motion, and then the SVOCs is released inside the SVOC concentration boundary layer adjacent to the surface. Concentration boundary …


Measurements And Simulation Of Conductor-Related Loss Of Pcb Transmission Lines, Oleg Kashurkin Jan 2016

Measurements And Simulation Of Conductor-Related Loss Of Pcb Transmission Lines, Oleg Kashurkin

Masters Theses

"With continuously increasing data rates Signal Integrity (SI) problems become more and more challenging. One of the main issues in high-speed data transfer is the frequency-dependent loss of transmission lines. This thesis is dedicated to conductor-related loss mechanisms in printed circuit board (PCB) transmission lines.

This thesis provides the experimental investigation of conductor properties used for fabrication of PCBs. Particularly, the resistivity and conductivity along with the temperature coefficients of eleven copper types is measured and reported. A four probe measurement technique is used. Results were verified by two independent measurements and show discrepancy of less than 0.5%.

Another major …


A Cost Benefit Analysis Of Sst Based Volt-Var Control, Guruprasad Ramani Jan 2016

A Cost Benefit Analysis Of Sst Based Volt-Var Control, Guruprasad Ramani

Masters Theses

"The overall objective of this thesis work is to improve system power quality with the help of solid state transformers (SSTs). Two methods to improve the system power quality are explored: a) achieving a unity power factor at all the load buses, and b) improving the system voltage profile to meet a desired voltage regulation requirement of 0.95


A Feasibility Study Of A Nuclear Power Plant With No Moving Parts, Jonathan Mark Schattke Jan 2016

A Feasibility Study Of A Nuclear Power Plant With No Moving Parts, Jonathan Mark Schattke

Masters Theses

"In a nuclear reactor design, every moving part in a system is considered a failure point. In this study, a proposal is made for designing a nuclear reactor that has no moving parts by coupling an accelerator driven core (removing control system moving parts) to a magnetohydrodynamic generator (removing power generation moving parts) using mercury coolant (removing pumping system moving parts). Further safety is realized by using a subcritical core, where the core is never able to sustain a chain reaction on its own, obviating many safety systems. The design is verified with a Monte Carlo simulation "--Abstract, page iii.


Thermal Characterization Of Phase Change Materials For Thermal Energy Storage, Rami Mohammad Reda Saeed Jan 2016

Thermal Characterization Of Phase Change Materials For Thermal Energy Storage, Rami Mohammad Reda Saeed

Masters Theses

"The study provides a valuable and useful database for Phase Change Materials (PCMs) for Thermal Energy Storage (TES) applications. Only a few existing studies have provided an overall investigation of thermophysical properties of PCMs in this detailed manner. Several organic PCMs, namely Myristic acid, Capric Acid, Lauryl Alcohol, Palmitic acid and Lauric acid, have been characterized after being carefully selected to cover wide range of TES applications. Insights and information gained from this work will be applied toward the design and modelling of many low temperature thermal energy storage applications. The study experimentally investigated uncertainty of thermal characterization of PCMs …


Design And Fabrication Of A System For The Additive Manufacturing Of Transparent Glass, Luke John Gilbert Jan 2016

Design And Fabrication Of A System For The Additive Manufacturing Of Transparent Glass, Luke John Gilbert

Masters Theses

"Despite glass' prevalence in the scientific and engineering community, very little research has been conducted attempting to additively manufacture (AM) glass. Even less research has been done on optically transparent glass. Glass’ material properties make it ineligible for most AM processes if the end result is to be transparent. Even small gas inclusions can cause large amounts of scattering. Additively manufacturing transparent glass brings the advantages found in other AM processes with the added benefit of having optical properties better than those found in polymers. Additively manufacturing glass also allows the optical properties of transparent parts to vary arbitrarily. This …


Multifunctional Wearable Epidermal Device For Physiological Signal Monitoring In Sleep Study, J V M S Avinash Kankipati Jan 2016

Multifunctional Wearable Epidermal Device For Physiological Signal Monitoring In Sleep Study, J V M S Avinash Kankipati

Masters Theses

"Sleep is the essential part of life. Thousands of people are suffering from different kinds sleep disorders. Clinical diagnosing and treating for such disorders are costly, painful and quite sluggish. To reach the demand many commercial products are into the market to encourage home based sleep studies using portable devices. These portable devices are limited in use, cannot be handled easily and quite costly. Advancements in technology miniaturized these portable devices to wearable devices to make them convenient and economical. Elastic, soft and thin silicon membrane with physical properties well matched with that of the epidermis provides conformal and robust …


Material Properties Characterization For Multilayer Pcb And Peec Macromodels For Above Plane Decoupling Capacitors, Xiang Fang Jan 2016

Material Properties Characterization For Multilayer Pcb And Peec Macromodels For Above Plane Decoupling Capacitors, Xiang Fang

Masters Theses

"Accurate frequency-dependent dielectric properties are important for accurate modelling of signal and power integrity problems. And decoupling capacitors perform an important function in the impedance reduction of power distribution systems. Hence, precise dielectric properties and micromodels for decoupling capacitors are the key parts for the signal and power integrity design.

In Section 1, the existing method for extracting dielectric properties from fabricated multilayer printed circuit boards based on the measured electrical property of fabricated transmission lines is introduced and validated using simulations. And the potential errors in the procedure are discussed. After that Djordjevic-Sarkar causal dielectric model for dielectric properties …


Shale Instability Of Deviated Wellbores In Southern Iraqi Fields, Ahmed Ali Shanshool Alsubaih Jan 2016

Shale Instability Of Deviated Wellbores In Southern Iraqi Fields, Ahmed Ali Shanshool Alsubaih

Masters Theses

"Wellbore instability problems are the cause for the majority of nonproductive time in the southern Iraqi fields' developments. The most severe problem in terms of effort and disbursement which is referred to a pipe sticking in Tanuma shale formation. Examining the drilling data revealed that this phenomenon was mostly related to the shear failure of the wellbore. Thus, a geomechanical analysis and drilling parameters/ practice optimization analysis were performed on a field in southern Iraq based on data from 45 deviated wells. The geomechanics analysis predicted the suitable drilling fluid density to prevent onset shear failure by using the Mogi-Coulomb …


Mechanistic Understanding Of Water-Rock Interactions During High-Salinity Water-Flooding Of Carbonate Reservoirs, Pu Han Jan 2016

Mechanistic Understanding Of Water-Rock Interactions During High-Salinity Water-Flooding Of Carbonate Reservoirs, Pu Han

Masters Theses

"Chemically tuned water-flooding provides a relatively cheap method of enhanced oil recovery from carbonate and sandstone reservoirs. Several possible recovery mechanisms such as mineral dissolution, multi-component ion exchange, double-layer expansion, adsorption/desorption from rock surface, reduction in interfacial tension, and fines migration that have been proposed are widely debated. The combination of these processes may result in wettability alteration that increases sweep efficiency of water-flooding. Here, wettability alteration due to water-rock interactions will be examined numerically.

To evaluate the wettability alteration, separation between breakthrough curves of the non-reactive component and the cations based on the chromatographic separation will be used due …


Hybrid Manufacturing Processes For Fusion Welding And Friction Stir Welding Of Aerospace Grade Aluminum Alloys, Megan Alexandra Gegesky Jan 2016

Hybrid Manufacturing Processes For Fusion Welding And Friction Stir Welding Of Aerospace Grade Aluminum Alloys, Megan Alexandra Gegesky

Masters Theses

"Friction stir welding and processing can provide for joints in aerospace grade aluminum alloys that have preferable material properties as compared to fusion welding techniques. Aerospace grade aluminum alloys such as AA2024-T3 and AA7075-T6 are considered non-weldable by traditional fusion welding techniques. Improved mechanical properties over previously used techniques are usually preferable for aerospace applications. Therefore, by combining traditional fusion welding and friction stir processing techniques, it could be plausible to create more difficult geometries in manufactured parts instead of using traditional techniques. While this combination of fusion welding and friction stir processing is not a new technology, its introduction …


A Study On Non-Metallic Inclusions In Foundry Steel Process, Marc Leonard Harris Jan 2016

A Study On Non-Metallic Inclusions In Foundry Steel Process, Marc Leonard Harris

Masters Theses

"The effects of sample area and automated SEM/EDS feature analysis parameters (step size, magnification and threshold) on nonmetallic inclusion characterization results has been investigated and optimized. A post-processing program was developed to automatically determine average inclusion chemistry, total element concentrations within inclusions, and for generating joint ternary diagrams with size visualization for representing nonmetallic inclusion populations. Using these tools the evolution of nonmetallic inclusions was examined for 4320 steel at a participating industrial steel foundry. The steel was sampled throughout electric arc furnace melting through ladle refining to the final casting where an in-mold sampling procedure was developed to procure …


Radiation Noise Source Modeling And Near-Field Coupling Estimation In Rf Interference, Liang Li Jan 2016

Radiation Noise Source Modeling And Near-Field Coupling Estimation In Rf Interference, Liang Li

Masters Theses

"With increasing complexities and shrinking size of modern electronic devices, the near-field RF interference issues are becoming challenging for RF-digital mixed circuit design. Predicting the coupling from digital module to RF antennas and mitigating RF interference is important to the system performance. The ultimate goal of this study is to address the desensitization issues existing in modern electronic devices that have mixed high speed digital-RF circuits, such as cellphone and wearable devices.

In order to estimate the near-field noise coupling from digital module to RF antennas, the noise source is anticipated to be replaced by its equivalent radiation model which …


Seismic Anisotropy And Mantle Dynamics Beneath The Southeastern United States Inferred From Shear-Wave Splitting Analysis, Yunhua Liu Jan 2016

Seismic Anisotropy And Mantle Dynamics Beneath The Southeastern United States Inferred From Shear-Wave Splitting Analysis, Yunhua Liu

Masters Theses

"Systematic spatial variations of mantle azimuthal anisotropy are revealed by over 3000 pairs of high-quality shear-wave splitting parameters (fast polarization orientations and splitting times) recorded at ~400 USArray and other network stations in the SE United States (75⁰-90⁰ W, and 24⁰-40⁰ N). The fast polarization orientations observed in the continental interior are subparallel to the absolute plate motion (APM) direction of the North American plate with apparent larger-than-normal splitting times, indicating a significant asthenospheric contribution. Fast orientations parallel to the edge of the North American craton are revealed along the southern and eastern margins of the continent. A portion of …


Study Jitter Amplification Of A Passive Channel And Investigation Of S₂₁ Magnitude Extraction Methodologies Using A Pattern Generator And Oscilloscope, Xinyun Guo Jan 2016

Study Jitter Amplification Of A Passive Channel And Investigation Of S₂₁ Magnitude Extraction Methodologies Using A Pattern Generator And Oscilloscope, Xinyun Guo

Masters Theses

"Recently the clock channel jitter amplification has been observed in several publications. Currently in many high-speed I/O systems, to avoid the cost and the complex clock recovery circuit design, people use traces forwarding clock signal from transmitting IC to receiving IC. When these clock traces are long enough, the amount of attenuation will induce not only inter-symbol-interference (ISI) but also modulate with the input jitter. Eventually it will lead some type of jitter been amplified after the channel. Similarly, the high speed communication channel (data channel) will also face this issue. Since there are no studies on the jitter amplification …


Evaluating Completion Performance For Gas Wells In The Upper And The Lower Montney Formation, Canada, Omar Qasim Mohammed Jan 2016

Evaluating Completion Performance For Gas Wells In The Upper And The Lower Montney Formation, Canada, Omar Qasim Mohammed

Masters Theses

"Identifying the key drivers for success of multiple fractured horizontal wells is not straightforward, especially in unconventional reservoirs like the Montney. Al-Alwani et al. (2015) provided a statistical analysis of Montney completions based on publicly available data. They showed that for the entire well population, cumulative gas recovery per stage, declines as the number of completed stages increase. However, their statistical analysis did not differentiate between completions in the Upper/Middle/Lower Montney, and did not include perforation cluster data.

This work documents the statistical analysis of 296 cased-hole horizontal gas well completions reported in the Upper and the Lower Montney. The …


Exhumation Of The Nacimiento Block: A Thermochronologic Analysis, Lisa Marie Arnold Lori Jan 2016

Exhumation Of The Nacimiento Block: A Thermochronologic Analysis, Lisa Marie Arnold Lori

Masters Theses

"Through the analysis of both U-Pb and (U-Th)/He ages from detrital zircon grains we can constrain thermal histories by establishing ages which correspond to crystallization and exhumation events, respectively. This combined geo-/thermochronologic approach is used here to constrain the history of the polyphase Nacimiento fault. This fault traverses central and southern California and has accumulated at least 150 km of slip since Late Cretaceous time. Major displacements along the structure occurred between 75 and 56 Ma, with Neogene to Holocene strike-slip remobilization linked to the San Andreas fault system. Detrital zircon U-Pb geochronology from Franciscan subduction assemblages west of the …


Managing Risks Of Market Price Uncertainty For A Microgrid Operation, Sriram Raghavan Jan 2016

Managing Risks Of Market Price Uncertainty For A Microgrid Operation, Sriram Raghavan

Masters Theses

"After deregulation of electricity in the United States, the day-ahead and real-time markets allow load serving entities and generation companies to bid and purchase/sell energy under the supervision of the independent system operator (ISO). The electricity market prices are inherently uncertain, and can be highly volatile. The main objective of this thesis is to hedge against the risk from the uncertainty of the market prices when purchasing/selling energy from/to the market. The energy manager can also schedule distributed generators (DGs) and storage of the microgrid to meet the demand, in addition to energy transactions from the market. The risk measure …


Carbon Transfer From Magnesia-Graphite Ladle Refractories To Ultra-Low Carbon Steel, Andrew Arthur Russo Jan 2016

Carbon Transfer From Magnesia-Graphite Ladle Refractories To Ultra-Low Carbon Steel, Andrew Arthur Russo

Masters Theses

"Ultra-low carbon steels are utilized in processes which require maximum ductility. Increases in interstitial carbon lower the ductility of steel; therefore, it is important to examine possible sources of carbon. The refractory ladle lining is one such source. Ladle refractories often contain graphite for its desirable thermal shock and slag corrosion resistance. This graphite is a possible source of carbon increase in ultra-low carbon steels. The goal of this research is to understand and evaluate the mechanisms by which carbon transfers to ultra-low carbon steel from magnesia-graphite ladle refractory.

Laboratory dip tests were performed in a vacuum induction furnace under …


Characterization Of Insertion Sequence Is605 In Halanaerobium Hydrogeniformans, Michael C. Sadler Jan 2016

Characterization Of Insertion Sequence Is605 In Halanaerobium Hydrogeniformans, Michael C. Sadler

Masters Theses

"Insertion sequences are the smallest prokaryotic transposable elements. These genes play a significant evolutionary role by promoting genome plasticity. Insertion sequences are highly diverse elements that have largely been uncharacterized. As such, the ability to accurately identify, annotate, and infer genomic impact of insertion sequences is lacking. The study of new insertion sequences contributes knowledge to their annotation and evolution. Halanaerobium hydrogeniformans is a unique organism with an abnormally high number of insertion sequences. A family of insertion sequences, IS200/605, showed several interesting distinctions from other elements in the genome, including severe open reading frame degradation, and was characterized in …


Understanding User Experience In Gaming, Sri Chaitanya Sanaboina Jan 2016

Understanding User Experience In Gaming, Sri Chaitanya Sanaboina

Masters Theses

"This research examines the effect of virtual reality gaming versus desktop based gaming on spatial presence, social presence, and intention to play. It draws on cognitive theory of presence, social presence theory, and theory of reasoned action to generate the research hypotheses and explain the observed phenomenon. A within-subject experimental design (N=53) was used to evaluate the effects of virtual reality versus desktop based gaming. The results suggest that both spatial presence and social presence were significantly enhanced in the virtual reality gaming environment while intention to play was significantly greater in the desktop based gaming environment"--Abstract, page iii.


Characterization Of Fracture Initiation In Non-Cylindrical Buckle Folds Using 3d Finite Element Analysis, Eli Jacob Steinbeck Jan 2016

Characterization Of Fracture Initiation In Non-Cylindrical Buckle Folds Using 3d Finite Element Analysis, Eli Jacob Steinbeck

Masters Theses

"The spatial distribution of fracture sets associated with buckle folds has been well documented in field studies. There are difficulties, however, in placing accurate constraints on the timing of the initiation of individual fracture sets during the deformation history of the fold under in-situ conditions. This study investigates specific conditions that give rise to the initiation of various fracture sets in the hinge and limb of a pericline, based on an analysis of the effective stress evolution during the processes of buckling and erosional unloading. A 3D finite element modeling approach is used to simulate the effective stress evolution in …


Engine Sound Simulation And Generation In Driving Simulator, Shuang Wu Jan 2016

Engine Sound Simulation And Generation In Driving Simulator, Shuang Wu

Masters Theses

"Simulating a driving environment that provides engine sound as auditory feedback to the driver is a challenging task due to the complexity of engine sound, a wide range of operating speeds, and repeated sound clicking during playback. This thesis describes a method of engine sound simulation and generation for a driving simulator. By analyzing sample sounds, spectral modeling synthesis was used to decompose the sound samples into deterministic and stochastic components. Then, the modeled deterministic and stochastic signals were employed to resynthesize the sounds. To represent engine sounds not available in the recorded database, sound interpolation was applied to two …


Fluid Flow Through Deformation Band, Huining Zhang Jan 2016

Fluid Flow Through Deformation Band, Huining Zhang

Masters Theses

"Cataclastic deformation bands, which are common in porous sandstone, have the potential to restrict fluid flow. Geological studies have shown that permeability of deformation band shear zones can be one to five orders of magnitude less than for the sandstone host rock. However, recent studies based on simplified analytical estimates have shown that fluid flow in jointed deformation bands may not be retarded since joints play an important role in conducting fluids. In this study, 2 dimensional finite element analysis (FEA) is used to simulate the total discharge flow rate through jointed deformations. Variations of single planar and conjugate jointed …


Bridging The Gap Between Supply Chain And Consumer Experience, Cui Zou Jan 2016

Bridging The Gap Between Supply Chain And Consumer Experience, Cui Zou

Masters Theses

Many researchers agree that supply chain management is at the root of addressing customer values and increasing customer satisfaction. However, in reality the route to accomplishing these goals is not so clearly defined. The studies herein attempt to shed some insight on a special perspective to bridge the gap between supply chain and customer experience. The ideas behind these studies explore the notion that customer experience can be impacted by a vast spectrum of factors from suppliers to even the specific mobile commerce (m-commerce) tools they use.

To gain insight into the supplier dimension of the supply chain, a survey …


Exploring Reservoir Connectivity With Production Data: Two New Methods And A New Technique, Ghazwan Faisal Jasim Al-Khmaysawee Jan 2016

Exploring Reservoir Connectivity With Production Data: Two New Methods And A New Technique, Ghazwan Faisal Jasim Al-Khmaysawee

Masters Theses

"This study presents two new, simple methods to explore reservoir connectivity, which has a significant impact on field development strategy. Identifying reservoir connectivity during primary depletion plays an important role in achieving the most cost-effective and highest production possible. It is also very important in future secondary and tertiary oil recovery, particularly when costs dictate a limited number of wells such as those in deepwater environments.

The presented methods are reciprocal-productivity index versus total field material-balance time trend lines and reciprocal-productivity index versus time trend lines. Those two methods are quick, simple, inexpensive, and only need rate and pressure data …


Analysis Of Va Sacramento Medical Center Capacity Using Discrete Event Simulation, Tatiana Alejandra Cardona Jan 2016

Analysis Of Va Sacramento Medical Center Capacity Using Discrete Event Simulation, Tatiana Alejandra Cardona

Masters Theses

"The development of simulation models continues to provide effective solutions to a wide range of problems in healthcare systems. In the research presented within this thesis is the development of a representative and validated discrete event simulation model for the purpose of evaluating additional capacity. The study consists of a detailed exploratory analysis, verification and validation tests of the simulation results, and a thorough design of experiments. The exploratory analysis consisted of developing simulation models that provide similar characteristics found in the data. The design of experiments consisted of generating scenarios of various bed additions in the hospital units of …


Accurate Imepdance Measurement Of O Clip And Near Field Coupling Estimation Using Equivalent Dipole Moment Model, Qiaolei Huang Jan 2016

Accurate Imepdance Measurement Of O Clip And Near Field Coupling Estimation Using Equivalent Dipole Moment Model, Qiaolei Huang

Masters Theses

"As cellphones and electronic devices moves towards higher date rates yet smaller form factor, designer face more electromagnetic interference (EMI) and radio frequency interference (RFI) problems. In order to better guide the early design; designers want to know the exact electrical performance of small components, coupling estimation between components.

In Section 1, a de-embedding method is proposed to measure the impedance of an innovative O-shape spring contact, for frequency up to 30 GHz. The measurements are performed under the same condition when it's actually used in cellphones. De-embedding method will be applied to remove the fixture effects of the measurement …


Bioresponsive Polymer Coating On Nanoparticles, Tunyaboon Laemthong Jan 2016

Bioresponsive Polymer Coating On Nanoparticles, Tunyaboon Laemthong

Masters Theses

"Nanotechnology incorporated with molecular biology became a promising way to treat cancer. The size of nanoparticles enables them to overcome the side effects noticed in cancer treatment like chemotherapy and surgery. Various types and shapes of nanoparticles have been synthesized and used in drug delivery to tumor sites. However, one of problems of using these nanoparticles is the aggregation after injecting them into human body due to flow rate of bloodstream. The coagulation and aggregation will result in clogging blood vessel and lower therapeutic efficacy.

In this thesis, a solution to the aggregation problem was proposed, which is coating biopolymer …


Using Eye-Tracking To Understand User Behavior In Deception Detection System Interaction, Prashanth Kumar Lakkapragada Jan 2016

Using Eye-Tracking To Understand User Behavior In Deception Detection System Interaction, Prashanth Kumar Lakkapragada

Masters Theses

"This research presents the analysis of data collected using eye-tracking devices on user interaction with a deception detection system. The differences between two groups of subjects, namely Innocent and Guilty, were compared, where Innocent subjects did not carry any explosive and hence, had nothing to hide in declaring objects that they were carrying whereas Guilty subjects had to lie to deceive the system. The results indicate that there is no significant difference in pupil dilation between the Innocent and Guilty subjects. However, the amount of fixations on the empty spaces of slides containing an explosive image can be used to …