Digital Commons Network^™

Imaging Reinforced Concrete: A Comparative Study Of Ground Penetration Radar And Rebarscope, Abhishek Kodi

Masters Theses

"Geophysical techniques have been playing a very vital role in subsurface imaging in the recent past. Technology has been making it both reliable and convenient to utilize non-destructive geophysics techniques like Ground Penetration Radar, Induction current based Rebarscope, Seismic methods, ERT, etc. The applications range from shallow subsurface investigation of Bridge decks to old tunnels, mapping of rabars in a pre-existing construction and analyzing the concrete strength.

The thesis constitutes of a comparative study and analysis of a Ground Penetration Radar system and a Rebarscope. Individual parameters obtained directly from the study and obtained indirectly from the study shall be …

Assessing Downstream Stormwater Impacts For Urban Watershed Planning, Johanna Meyer Pavlowsky

Masters Theses

"The urbanization of watersheds has caused debilitating effects to downstream aquatic ecosystems in catchments and streams. The implementation of green infrastructure (GI), such as permeable pavements and bioretention facilities, has been shown to alleviate these effects by both reducing runoff and mitigating pollutants; however, the implements are often not designed with a specific goal of water improvement. This study targets understanding a small, impaired urban watershed, and the benefits green infrastructure may have to provide environmental, social, and economic improvement to the watershed.

Portions of Rolla including much of the S&T campus drain into the impaired urban waterbody Frisco Lake, …

Application Of Embedded Frequency Selective Surfaces For Structural Health Monitoring, Dustin Franklin Pieper

Masters Theses

"This thesis proposes the use of Frequency Selective Surfaces (FSSs) as an embedded structural health monitoring (SHM) sensor. FSSs are periodic arrays of conductive elements that filter certain frequencies of incident electromagnetic radiation. The behavior of this filter is heavily dependent on the geometry of the FSS and local environment. Therefore, by monitoring how this filtering response changes when the geometric or environmental changes take place, information about those changes may be determined. In previous works, FSS-based sensing has shown promise for sensing normal strain (a stretching or compressing geometrical deformation). This concept is extended in this thesis by investigating …

Numerical Analysis Of Flexural Slip During Viscoelastic Buckle Folding, Davi Rodrigues Damasceno

Masters Theses

"Flexural slip is considered to be an important folding mechanism contributing in the development of different folds such as chevron, and kink-band buckle folds. Various filed studies have provided a general conceptual and qualitative understanding of flexural slip. However, quantitative evidence of the importance of the flexural slip mechanism during fold evolution is sparse, as the actual amount of surface parallel displacement, and timing, is difficult to measure accurately, due to the lack of suitable strain markers.

In this study 2D finite element analysis is used to overcome these disadvantages and to simulate flexural slip during viscoelastic buckle folding. Variations …

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

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 …

Data Analysis Of Surfactant-Induced Wettability Alteration In Carbonate Reservoirs, Hao Sun

Masters Theses

"Most carbonate formations prove to be oil-wet due to oil aging effect. Therefore it is essential to employ wettability alteration methods for a more effective enhanced oil recovery process. It is confirmed by researchers that surfactant treatment has positive effects on wettability alteration of carbonate rock, from strong oil-wet to intermediate wet or to even weak water-wet. A number of experiments have the same conclusion and yet, a systematic screening guide development with the support of sufficient data analysis is lacking.

This study involves screening guide development for surfactant-induced wettability alteration method. 199 experiments collected from published literatures are analyzed …

Automated Channel Emulator Based On Mems Switch And Improvement Of Signal Transition, Jingdong Sun

Masters Theses

"Channel Emulator, which is widely used in communication system development, is an instrument that emulates the real-world signal propagation environment between transmitter and. [sic] To overcome the disadvantages of traditional channel emulator, we propose a novel structure of the automated channel emulator in Section 1, which can be controlled by software and integrated into auto-testing system. MEMS switch, with good RF performance, is used to connect and isolate multiple channels.

In Section 2, we divide the whole channel emulator system into Channel, Support, and Controller Board, and provide detailed design procedures with critical parameters of each board. The well-designed high …

Effect Of Reservoirs Heterogeneity On Injection Pressure And Placement Of Preformed Particle Gel For Conformance Control, Ze Wang

Masters Theses

"Preformed particle gels (PPG) have been successfully applied as a plugging agent for plugging fractures and then divert displacing fluid into poorly swept zones. However, PPG propagation and plugging mechanisms through open fractures have not been studied thoroughly.

This work investigated the influence of some factors (particle size, brine concentration, heterogeneity, and brine salinity) on gel injectivity, plugging performance for water flow through open fractures. Five-foot tubes were used to mimic open fractures. Three models were designed to conduct the work, including (1) single fracture with uniform fracture width, (2) single fracture with different widths, and (3) two parallel fractures …

3d Seismic Structural And Stratigraphic Interpretation Of The Tui-3d Field, Taranaki Basin, New Zealand, Gorkem Yagci

Masters Theses

"Identifying seismic structures and stratigraphy are important for exploration of hydrocarbons. The purpose of this study is to discover seismic structural and stratigraphic features and to utilize the results for interpreting depositional environments. A 3D seismic dataset from the Tui-3D Field, the Taranaki Basin, New Zealand with well data were used to visualize structures, to detect stratigraphic features, to identify main lithology, to understand depositional environment, and to describe seismic facies and reflection patterns of the target horizons. The major formations are in the Kapuni Group.

Seismic structural interpretation indicates thirty-two minor faults, which may play an important role in …

Study On The Applicability Of Relative Permeability Modifiers For Water Shutoff Using Numerical Simulation, Dheiaa Khafief Khashan Alfarge

Masters Theses

"Water production is a challenging problem to be controlled during hydrocarbon-reservoirs production life. Disproportionate Permeability Reduction (DPR) is often used as water shutoff treatment in production wells when other conventional solutions like mechanical isolations are difficult to perform. This study applied numerical simulation methods to diagnose the factors impacting DPR treatment success on macroscopic level and to see when, where and at which conditions DPR treatment can give best results.

This work indicated that the following points should be considered before DPR treatment is executed in any reservoir to get a successful treatment. Firstly, this research explored that DPR performance …

Design And Analysis Of An Axisymmetric Aerospike Supersonic Micro-Nozzle For A Refrigerant-Based Cold-Gas Propulsion System For Small Satellites, Abdalla Ali Bani

Masters Theses

"The cold-gas propulsion system being developed by M-SAT requires improvements to its original nozzle design. This study documents the research, design, and analysis of a supersonic plug nozzle concept that could be integrated to the refrigerant-based cold-gas propulsion system to possibly improve its performance. As documented in this thesis, CFD analysis showed that the outlined nozzle design method resulted in a feasible nozzle concept that has the ability to out-perform a conventional nozzle of the same area ratio. The flow-fields and thrust of the aerospike nozzle, for the full and truncated nozzles, were investigated. The purpose of this study is …

Voltage Control In A Distribution System Using Active Power Loads, Mounika Chava

Masters Theses

"High penetration of renewable energy resources such as rooftop solar photovoltaic (PV) systems is exacerbating violations of the voltage limits in power distribution networks. Existing solutions to these over-/under-voltage issues include tap-changing transformers and shunt capacitors. However, tap changers only allow voltage changes in discrete steps and shunt capacitors cannot handle over-voltage situations. To overcome these problems, this thesis proposes voltage control in a distribution system by adjusting active power loads. The proposed solution can be used for both under- and over-voltage cases at any levels of voltage adjustment. First, the active power that needs to be adjusted at selected …

De-Embedding Method For Electrical Response Extraction Of Through-Silicon Via (Tsv) In Silicon Interposer Technology And Signal Integrity Performance Comparison With Embedded Multi-Die Interconnect Bridge (Emib) Technology, Qian Wang

Masters Theses

"Traditional two-dimensional system-in-package (2D SiP) can no longer support the scaling of size, power, bandwidth, and cost at the same rate required by Moore's Law. Three-dimensional integrated circuits (3D-ICs), 2.5D silicon interposer technology in which through silicon vias are widely used, are implemented to meet these challenges. Embedded multi-die interconnect bridge (EMIB) technology are proposed as well.

In Section 1, a novel de-embedding method is proposed for TSV characterization by using a set of simple yet efficient test patterns. Full wave models and corresponding equivalent circuits are provided to explain the electrical performance of the test patterns clearly. Furthermore, broadband …

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 …

Deterministic Simulation Of Thermal Neutron Radiography And Tomography, Rajarshi Pal Chowdhury

Masters Theses

"In recent years, thermal neutron radiography and tomography have gained much attention as one of the nondestructive testing methods. However, the application of thermal neutron radiography and tomography hindered by their technical complexity, radiation shielding, and time-consuming data collection processes. Monte Carlo simulations have been developed in the past to improve the neutron imaging facility's ability. In this present work, a new deterministic simulation approach has been proposed and demonstrated to simulate neutron radiographs numerically using a ray tracing algorithm. This approach has made the simulation of neutron radiographs much faster than by previously used stochastic methods (i.e Monte Carlo …

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 …

Avon Alkaline Igneous Province, Missouri: Characterization Of Subcontinental Mantle Source And Evolution Via Chemical Analysis Of Olivine, Zachary William Freeman

Masters Theses

"This article presents the crystallization age of, and composition of olivine phenocrysts within an alnoite of, the Avon Alkaline Igneous Province (AAIP) of Ste. Genevieve County, Missouri. The AAIP is an ultramafic igneous province consisting of approx. 80 known intrusives of diverse lithology and texture. ⁴⁰Ar/³⁹ Ar geochronology indicates an emplacement age of 386 +/- 1 Ma, which establishes the AAIP as the only known Devonian-age ultramafic igneous body in the Midwestern U.S. Study of the AAIP provides a unique opportunity to characterize the Devonian-age subcontinental mantle and the processes that generated the suite of ultramafic rocks present …

The Evaluation Of Sequential Optimization And Reliability Analysis, Guannan Liu

Masters Theses

"Sequential Optimization and Reliability Assessment (SORA) has been used for more than one decade for reliability-based design (RBD), but comprehensive theoretical studies on its performance have not been conducted. Further investigations on its performance are still needed. The objective of this thesis is to evaluate the performance of SORA for various testing problems. The performance of SORA evaluated in this thesis includes (1) accuracy, (2) efficiency, and (3) convergence behavior or robustness with numerical testing problems. SORA is evaluated with comparison with other major RBD methodologies. The testing problems are in different scales (numbers of design variables, random variables, and …

Pricing Of Geometric Asian Options In General Affine Stochastic Volatility Models, Johannes Ruppert

Masters Theses

"In this thesis, we look at the general affine pricing model introduced in [11]. This model allows to price geometric Asian options, which are of big interest due to their lower volatility in comparison to, for example, European options. Because of their structure and in order to be able to price these options, we look at the basic theory of Lévy processes and stochastic calculus. Furthermore, we provide the detailed description of the parameters of the pricing formulas for some popular specific single-factor stochastic volatility models with jumps and generalize the approach of [11] to multi-factor models"--Abstract, page iii.

Paleogeogra Detrital Zircon Geochronology Of Upper Cambrian To Lower Mississippian Siliciclastic Strata Of The Ozark Dome And Vicinity, Bing Li

Masters Theses

"Siliciclastic strata exposed in the Ozark Dome provide Late Cambrian to Late Cretaceous snapshots of an evolving paleogeology and regional to far-field tectonic events. U-Pb ages of detrital zircons from the arkosic base of the Upper Cambrian Lamotte Formation reflect first cycle derivation from the adjacent ca. 1.31-1.48 Ga Granite-Rhyolite province, with subsidiary input from ca. 1.6-1.7 Ga Mazatzal basement. Feldspathic arenites near the top of the Lamotte Sandstone also contain significant quantities of detrital zircon grains of these ages, with additional peaks centered at ca. 2.7 and ca. 1.1 Ga, signaling the onset of extra-regional detrital input most likely …

A Linear Matrix Inequality-Based Approach For The Computation Of Actuator Bandwidth Limits In Adaptive Control, Daniel Robert Wagner

Masters Theses

"Linear matrix inequalities and convex optimization techniques have become popular tools to solve nontrivial problems in the field of adaptive control. Specifically, the stability of adaptive control laws in the presence of actuator dynamics remains as an important open control problem. In this thesis, we present a linear matrix inequalities-based hedging approach and evaluate it for model reference adaptive control of an uncertain dynamical system in the presence of actuator dynamics. The ideal reference dynamics are modified such that the hedging approach allows the correct adaptation without being hindered by the presence of actuator dynamics. The hedging approach is first …

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 …

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 …

Design Methodology For Behavioral Surface Roughness Modeling And High-Speed Test Board Design, Xinyao Guo

Masters Theses

"A behavioral model is introduced, which can predict low-loss and low surface roughness transmission line time- and frequency- domain performances. High data rates push for better performance of PCB transmission lines. However, the roughness of copper foil has a considerable impact on the signal integrity performance of transmission lines at high data rates and long propagation distance. Existing models for low-loss transmission line surface roughness are inadequate. A new behavioral model to represent the surface roughness has been developed. The model is applied in the design process by adding a dispersive term to the bulk dielectric permittivity to represent the …

Late Ordovician Tectonism In The North American Midcontinent: Constraints From U-Pb Detrital Zircon Geochronology, Daniel Nathan Meehan I

Masters Theses

"Numerous sandstone filled depressions hosted in upper Cambrian to Middle Ordovociain dolostones in south-central Missouri have historically been identified as Pennsylvanian paleokarst structures. U-Pb detrital zircon geochronology is at odds the time of formation and sedimentological evidence challenges their classification. "Filled sink" deposits yield primary zircon age populations of 2.8-2.6 Ga (~50% of all analyzed grains), 1.2-1.1 Ga (~25%), 1.8-1.6 Ga (~15%) and 1.5-1.3 Ga (~10%). These zircon populations most likely originated from the Superior Craton and Midcontinent Rift and/or Grenville orogen, respectively. The Warrensburg and Moberly channel-fill sandstones of central Missouri were identified as good candidates for Pennsylvanian aged …

An Investigation Of The Nexus Between Poverty And The Informal Sector In Developing Economies: A Case Study Of Nigeria, Omotara Adeeko

Masters Theses

This paper examines the relationship between poverty and the informal sector in Nigeria. In order to achieve this objective both primary and secondary sources of data mostly spanning from 1980 to 2014 are utilized. The methodology follows three stages. First, the Granger causality test is performed to determine the direction of causality. Using that information, a baseline model, along with several variants, is built on the next stage. Lastly, a robustness check is completed to ensure that the results do not exhibit severe spuriousness problems.

Granger causality tests indicate that the informal sector causes poverty. Overall, nine models including some …

An Intersectional Analysis Of Male Student-Athletes' Meaning-Making About Masculinity, Michelle Lisack

Masters Theses

Men's athletics is often viewed as an environment where hegemonic masculinity is perpetuated, though some believe this environment provides a safe space for men to break away from hegemonic masculinity. This study was designed to gain an understanding of how male student-athletes experience masculinity and how the context of athletics influences meaning-making about masculinity. Using a phenomenological approach, the researcher interviewed five male student-athletes and observed the practice sessions of two different teams. The participants were student-athletes of junior or senior status from the following sports: tennis, soccer, swimming, baseball, and basketball. Results showed that male student-athletes found it challenging …

Genesis B From Ms Junius 11 And Paradise Lost: Possible Connections, Alicia D. Arnold

Masters Theses

This thesis looks at the ongoing debate concerning John Milton's potential use of Genesis B from MS Junius II when creating Paradise Lost. Much of the thesis looks at the probability of John Milton's ability to access or know Genesis B. Included is an annotated translation of "Satan in Hell" from Genesis B. The last chapter looks at the given translation and Paradise Lost to see if there are similarities in dialect, theme, and word-choices, or if Paradise Lost has Old English markers. The conclusion is that the debate must continue as there is currently not enough evidence to prove …

Stress As A Moderator Of Visual Perception: Do Elevated Stress Levels Interfere With Visual Cognition?, Ashley Ebersole

Masters Theses

Stress is an unavoidable aspect of human life, and despite a large body of research on stress, the relationship between chronic or traumatic stress and cognition is not yet fully explained. One component lacking research is visual attention, an area of visual cognition which is an essential part of our ability to interact with the world around us. This is especially true in the context of trauma and stress related disorders, and having a better understanding of how traumatic stress impacts attention and perception can inform psychotherapy for these issues. The current study aims to conceptualize how stressors impact the …