Digital Commons Network^™

Provenance And Depositional Environments Of Fluvial-Lacustrine Deposits In A Non-Marine Rift Basin, Lower-Triassic Jiucaiyuan And Shaofanggou Low-Order Cycles Bogda Shan, Nw China, Jaimeson Grigaitis Fredericks

Masters Theses

"The uppermost Carboniferous to Lower Triassic eolian-fluvial-lacustrine deposits of Turpan-Junggar Basin, NW China, record the non-marine sediment-filling processes in a continental rift basin in mid-latitude NE Pangea. This study focuses on the fluvial-lacustrine strata of the Lower Triassic Jiucaiyuan (JCY) and Shaofanggou (SFG) low-order cycles (LCs) in multiple half grabens at the southern and northern foothills of Bogda Shan. Outcrop, paleocurrent, and petrographic analyses indicate a southern provenance. Intermediate to felsic volcanic lithics and metamorphic lithics are interpreted as being derived from Tian Shan to the south while the sedimentary lithics originate from the local rift shoulders. The basaltic lithics …

The Pantograph Equation In Quantum Calculus, Thomas Griebel

Masters Theses

"In this thesis, the pantograph equation in quantum calculus is investigated. The pantograph equation is a famous delay differential equation that has been known since 1971. Till the present day, the continuous and the discrete cases of the pantograph equation are well studied. This thesis deals with different pantograph equations in quantum calculus. An explicit solution representation and the exponential behavior of solutions of a pantograph equation are proved. Furthermore, several pantograph equations regarding asymptotic stability are considered. In fact, conditions for the asymptotic stability of the zero solution are derived and subsequently illustrated by examples. Moreover, an explicit solution …

Cloth-Air Partitioning Of Oxybenzone, Jonathan T. Hill

Masters Theses

"Clothing has been proven to be a significant accumulator of chemicals from the air. Semi-volatile organic compounds (SVOCs) have a high affinity towards textiles, and measuring the equilibrium partition coefficient between cloth and air (K_cloth-air) for SVOCs is crucial in predicting human exposure to these compounds. This study aims to quantify K_cloth-air for oxybenzone to contribute to a larger human exposure experiment carried out at the Technical University of Denmark (DTU). K_cloth-air for oxybenzone was calculated using data collected from the exposure chamber at DTU and from performing extractions of oxybenzone in fabric samples from the …

Personalizing Education With Algorithmic Course Selection, Tyler Morrow

Masters Theses

"The work presented in this thesis utilizes context-aware recommendation to facilitate personalized education and assist students in selecting courses (or in non-traditional curricula, topics or modules) that meet curricular requirements, leverage their skills and background, and are relevant to their interests. The original research contribution of this thesis is an algorithm that can generate a schedule of courses with consideration of a student's profile, minimization of cost, and complete adherence to institution requirements. The research problem at hand - a constrained optimization problem with potentially conflicting objectives - is solved by first identifying a minimal sets of courses a student …

Novel Approaches For Efficient Stochastic Computing, Ramu Seva

Masters Theses

"This thesis is comprised of two papers, where the first paper presents a novel approach for parallel implementation of SC using FPGA (Field Programmable Gate Array). This paper makes use of the distributed memory elements of FPGAs (i.e., look-up-tables -LUTs) to achieve this. An attempt has been made to build the stochastic number generators (SNGs) by using the proposed LUT approach. The construction of these SNGs has been influenced by the Quasi-random number sequences, which provide the advantage of reducing the random fluctuations present in the pseudo-random number generators such as LFSR (Linear Feedback Shift Register) as well as the …

Decodable Network Coding In Wireless Network, Junwei Su

Masters Theses

"Network coding is a network layer technique to improve transmission efficiency. Coding packets is especially beneficial in a wireless environment where the demand for radio spectrum is high. However, to fully realize the benefits of network coding two challenging issues that must be addressed are: (1) Guaranteeing separation of coded packets at the destination, and (2) Mitigating the extra coding/decoding delay. If the destination has all the needed packets to decode a coded packet, then separation failure can be averted. If the scheduling algorithm considers the arrival time of coding pairs, then the extra delay can be mitigated. In this …

Evaluation Of Swelling And Re-Swelling Of Preformed Particle Gels (Ppg) When Exposed To Co₂, Sujay Suresh

Masters Theses

"Long term water/gas flooding induces high permeability channels in reservoirs. Reservoir heterogeneity becomes the most prominent challenge faced in mature oil fields. Gel treatment has been a proven solution to counter the problem of reservoir heterogeneity, to provide in-depth treatment and improve the sweep efficiency for reservoirs. Preformed particle gels (PPGs) were developed as an alternative to in-situ gels as they preferentially penetrate and shutoff high permeability zones, leaving the low permeability zones undamaged. These gels have been predominantly used in water flooding projects, but have not been employed in carbon dioxide (CO₂) flooding projects. CO₂ Resistant …

Dc-Dc Converter Based Photovoltaic Simulator With A Double Current Mode Controller, Weichao Zhang

Masters Theses

"This thesis presents the performance of a DC-DC converter based with current mode controller photovoltaic (PV) simulator which emulates the output characteristics of a real PV module. A portable PV simulator prototype of 85 W is examined in terms of its steady state IV curve matching capacity and the convergence time corresponding to step change in current source load, voltage source load, and insolation levels. The current-voltage (IV) characteristics of the PV module are implemented as a look-up-table (LUT) which determines the reference output current from measured output voltage. A Thevenin Equivalent Method approach to PV arrays analysis is also …

Multi Stage Recovery From Large Scale Failure In Interdependent Networks, Maria Angelin John Bosco

Masters Theses

"Node and link failures that usually cause limited damage in a single network, may cascade into large scale disasters in the case of interdependent networks, due to the dependencies that exist between them. Recovery from such failures may require multiple stages or steps for complete restoration of connection or flow between them. When critical services are disrupted, the order in which the broken elements are repaired affects the earliest possible recovery time of vital services. In a flow network, one order of restoration may restore more flow at an earlier stage than another. The paper aims to model an efficient …

Comparison Of Voltage Regulation Between Sst And Conventional Transformers In High Penetration Pv Power Systems, Gautham Ashokkumar

Masters Theses

"Solid state transformers (SST) are power electronic transformers combined with high-frequency conventional transformers and control circuitry capable of delivering high performance and flexible power control capabilities. This thesis focuses on analyzing the performance of SSTs in a distribution system with photovoltaic (PV) injection. In order to validate the performance of SSTs, average value models are used on the IEEE 34 bus distribution feeder network scaled to 12.47 kV. SST voltage profiles on the load side are analyzed and the unity power factor capabilities are demonstrated. This is followed by the study of voltage profiles on the primary side of the …

Development Of A Variogram Approach To Spatial Outlier Detection Using A Supplemental Digital Elevation Model Dataset, Zane Daniel Helwig

Masters Theses

"When developing a ground water model, the quality of the dataset should first be evaluated. Spatial outliers can lead to predictions which are not representative of actual conditions. In order to isolate misrepresentative points, a method is presented which examines the experimental variogram of a ground water elevation dataset. To define a threshold variance between pairs of ground water elevation measures, ground elevation values from a digital elevation model (DEM) are used to determine a maximum reasonable variance expected to occur on the experimental variogram. To determine appropriate DEM parameters, a separate study was also done which observed characteristic behavior …

Imaging In Karst Terrain Using The Electrical Resistivity And Multichannel Analyses Of Surface Wave Methods, Ragab W. Jaafar

Masters Theses

"Electrical resistivity tomography and multi-channel analyses of surface waves data were acquired at a study area in Phelps County in the south-central part of Missouri. The objectives of the investigation were fourfold: 1) to image the subsurface in the study area to a depth of 70 feet; 2) to compare the ERT images generated using both the dipole-dipole and Wenner-Schlumberger arrays; and 3) to assess how variations in the MASW array configuration affected MASW data quality; and 4) to compare the ERT-estimated depth to top-of-rock and the MASW-generated depth to top-of-rock.

The subsurface in the study area was imaged to …

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

Masters Theses

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

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

Masters Theses

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

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

Effect Of Fracture Heterogeneity On Proppant Transport And Settling Mechanism, Dhurgham Abdulameer Kadhim

Masters Theses

"Proppant transport modeling through fractures with slickwater fluid systems assumes uniform and homogeneous fracture widths by implying constant fluid behavior at wall boundaries. Hydraulic fracturing mineback operations have demonstrated that induced fractures are heterogeneous and varying in width. This work investigates the impact of fracture width heterogeneity, roughness, and leak-off on ceramic proppant transport and settling, using proppant distribution concepts of Equilibrium Dune Level (EDL) and equilibrium Dune Length (EDX). Experimental work was conducted to investigate the impact of fracture width heterogeneity by varying fracture width along two plexiglass sheets. To mimic actual hydraulic fractures, the injection side was designed …

Nuclei Segmentation Using Level Set Method And Data Fusion For The Cin Classification, Ravali Edulapuram

Masters Theses

"This paper deals with the automation of the detection of the cervical cancer through histology images. This process is divided into two parts, corresponding to segmentation and data fusion. The segmentation and classification of the cervical epithelium images is done using hybrid image processing techniques. The digitized histology images provided have a pre-cervical cancer condition called cervical intraepithelial neoplasia (CIN) by expert pathologists. Previously, image analysis studies focused on nuclei-level features to classify the epithelium into the CIN grades. The current study focuses on nuclei segmentation based on the level set segmentation and fuzzy c-means clustering methods. Morphological post-processing operations …

Entropy-Based Performance Analysis Of Jet Engines; Methodology And Application To A Generic Single-Spool Turbojet, Mohammad Abbas

Masters Theses

"Recently developed methodology that provides the direct assessment of traditional thrust-based performance of aerospace vehicles in terms of entropy generation (i.e., exergy destruction) is modified for stand-alone jet engines. This methodology is applied to a specific single-spool turbojet engine configuration. A generic compressor performance map along with modeled engine component performance characterizations are utilized in order to provide comprehensive traditional engine performance results (engine thrust, mass capture, and RPM), for on and off-design engine operation. Details of exergy losses in engine components, across the entire engine, and in the engine wake are provided and the engine performance losses associated with …

2-D And 3-D Mapping Of Soil And Rock Structure In Karst Terrain Of Southwestern Missouri Using The Non-Invasive Electrical Resistivity Tomography Method (Ert), Diya Ali Ahmad Alfuqara

Masters Theses

"Electrical resistivity tomography data were acquired in an extensively karstic area of southwestern Missouri. The interpretation of the electrical resistivity tomography data was constrained by multichannel analysis of surface wave data and limited boring control. The objective of the study was to determine if variations in the moisture content of the soil and shallow rock are related to ground surface topography. Analysis of the acquired electrical resistivity tomography data showed that resistivity values of soil and shallow rock beneath and in proximity to identified natural and man-made surface run-off pathways are typically low compared to the resistivity values of soil …

The Viability Of Advantg Deterministic Method For Synthetic Radiography Generation, Andrew Albert Bingham

Masters Theses

"Time sensitive and high resolution image simulations are needed for synthetic radiography generation. The standard stochastic approach requires lengthy run times with poor statistics at higher resolutions. The investigation of the viability of a deterministic approach to synthetic radiography image generation was explored. The aim was to analyze a computational time decrease over the stochastic method. ADVANTG was compared to MCNP in multiple scenarios including a Benchtop CT prototype, to simulate high resolution radiography images. By using ADVANTG deterministic code to simulate radiography images the computational time was found to decrease over 10 times compared to the MCNP stochastic approach"--Abstract, …

Cfd Validation And Scaling Of Condensation Heat Transfer, Varun Kalra

Masters Theses

"A CFD study was performed using STAR-CCM+ to validate the software for its competence in the prediction and scaling of condensation heat transfer in the presence of air acting as a non-condensable gas. Three vertical concentric tube heat exchanger geometries with different diameters were studied in the CFD analysis. It was seen that the steam bulk temperatures predicted by STAR-CCM+ closely matched the experimental data. However, the temperatures of outer wall of the steel condenser tubes showed a deviation of 2% to 11% from the experimental values. The error in adiabatic water wall temperatures were found to range from 18% …

Spectrum Analyzer Based Phase Measurement For Emi Scanning Applications, Shubhankar Marathe

Masters Theses

"Often Electromagnetic Interference (EMI) scanning applications require phase and magnitude information for the creation of equivalent radiation models and for far-field predictions. Magnitude information can be obtained using a spectrum analyzer (SA), which is relatively inexpensive compared to phase resolving instruments such as oscilloscopes (scope) and vector network analyzers (VNA). The study focusses on the development of a near-field scanning method using a SA to measure the phase of the device under test (DUT) signals.

The first part deals with the development of the method in software simulation tools and testing it under standard test conditions. The second part deals …

A Review Of Random Matrix Theory With An Application To Biological Data, Jesse Aaron Marks

Masters Theses

"Random matrix theory (RMT) is an area of study that has applications in a wide variety of scientific disciplines. The foundation of RMT is based on the analysis of the eigenvalue behavior of matrices. The eigenvalues of a random matrix (a matrix with stochastic entries) will behave differently than the eigenvalues from a matrix with non-random properties. Studying this bifurcation of the eigenvalue behavior provides the means to which system-specific signals can be distinguished from randomness. In particular, RMT provides an algorithmic approach to objectively remove noise from matrices with embedded signals.

Major advances in data acquisition capabilities have changed …

Mold Flux Crystallization And Mold Thermal Behavior, Elizabeth Irene Peterson

Masters Theses

"Mold flux plays a small but critical role in the continuous casting of steel. The carbon-coated powder is added at the top of the water-cooled copper mold, over time it melts and infiltrates the gap between the copper mold and the solidifying steel strand. Mold powders serve five primary functions: (1) chemical insulation, (2) thermal insulation, (3)lubrication between the steel strand and mold, (4) absorption of inclusions, and (5)promotion of even heat flux. All five functions are critical to slab casting, but surface defect prevention is primarily controlled through even heat flux. Glassy fluxes have high heat transfer and result …

Shortest-Distance And Minimum-Cost Self-Charging Path Problems: Formulations And Application, Marc Monroe Teeter

Masters Theses

"In this study, self-charging paths for an electric bus are analyzed. Wireless-power-transfer technologies, when integrated on a road network, enable dynamic charging of electric vehicles. Roads implemented with a wireless-power-transfer technology are referred to as electric-roads in this study. Electric vehicles traversing on electric-roads, therefore, can be dynamically charged. This can further eliminate the need for static charging, i.e., the electric vehicle will not need to stop for charging.

This thesis analyzes the design of transit routes for an electric-bus so that the electric-bus is charged by only electric-roads. Specifically, the focus is on designing a path, which passes through …

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

Masters Theses

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

Mining Asteroids For Volatile Resources: An Experimental Demonstration Of Extraction And Recovery, Egboche Christopher Unobe

Masters Theses

"Gaseous compounds trapped within carbonaceous asteroids may prove to be important targets for prospective space miners in the near-term. Volatile release is from hydrated, hydroxylated and carbonated phases present, making such bodies attractive as feedstock for the production of H₂O, CO₂ and simple organic compounds. A source of these species in orbit provides an opportunity to locally produce space-craft propellant and other life-support gases through the application of In-situ Resource Utilization (ISRU).

For this study, an experimental vacuum system was modified and used to test the technical validity of radiatively heating asteroid simulants to extract contained gaseous …

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

Masters Theses

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

Developing Restoration Schemes For A Road Transportation Network In The Event Of A Disaster, Ebin Antony

Masters Theses

"Transportation systems such as rail, road, and waterways are key component of critical infrastructure systems, providing connectivity between other components to enable the production and distribution of goods and services. During large scale disasters such as earth quakes and floods, this connectivity is disrupted, restricting or completely halting the flow of goods and services. To ensure that the connectivity between the different modes of transportation are restored in an aftermath of these disruptions, the interdependence between them and the importance of individual elements to the overall connectivity have to be studied and formulated to develop a system-level restoration plan. This …

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

Masters Theses

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

Quantifying Ceramic Proppant Transport In Complex Fracture Networks, Vivekvardhan Reddy Kesireddy

Masters Theses

"Water fracs have become an essential part of unconventional reservoirs to create deeper fracture networks. Proppant transport in water fracs is challenging in terms of fluids ability to carry the proppant deeper into these fracture networks. This experimental study investigates the impact of the flow rates, fracture widths and complexity controlling the ability of proppant to flow into complex fracture networks. This research attempts to nullify the knowledge gap in understanding width heterogeneity in primary and secondary fractures. This study speaks for settling pattern and proppant transport through a slot flow model with a unique approach to understand stage wise …