Digital Commons Network^™

Evaluation Of Millimeter-Sized Preformed Particle Gel For Conformance Control Treatments Using Simple Models, Ali Abdulmohsen Al Brahim

Masters Theses

Millimeter-sized preformed particle gels (PPGs) have been successfully used to tackle the high-permeable zones, fractures and channels in mature oilfields for conformance control improvement. PPGs can significantly reduce the permeability of abnormal fractures and divert injected water to the low permeable zones where hydrocarbon was not swept by previous water flooding. Due to the irregularity of PPGs in shapes after swollen, their strength cannot be easily measured using the conventional methods. Therefore, the open hole screen plate models with various hole diameters and density were designed to establish a simple technique that can be used to measure the strength of …

Palynological Interpretations Of Deep Sea Drilling Projects Cores In The Gulf Of Mexico And Bahamian Platform, Adam Patrick Barron

Masters Theses

"One hundred drill core samples were from Deep Sea Drilling Project (DSDP) Sites 94, 98, and 540 were investigated for their palynological contents (pollen, spores, acritarchs, dinoflagellate cysts, and dispersed organic matter) to infer the paleoenvironmental and paleoceanographic history of the Gulf of Mexico and the Bahamian Platform during the middle Eocene to middle Miocene interval. At Sites 94 and 540, abundant dinoflagellate cysts (chiefly Operculodinium centrocarpum, Lingulodinium machaerophorum, Impagidinium sp., Nematosphaeropsis sp., and Spiniferites spp.) were used as paleoenvironmental indicators. Two alternating palynofacies assemblages were identified from dispersed organic matter analysis: terrestrially influenced assemblage A and marine dominated assemblage …

Neutronic Analysis Of Light Water Small Modular Reactor With Flexible Fuel Configurations, Brendan Dsouza

Masters Theses

"The study was focused on the analysis of light water Small Modular Reactor (SMR) with flexible fuel configurations. The core design, based on the Westinghouse UO₂ SMR with less than 5% enrichment was developed using the Monte Carlo N-Particle (MCNP) code. Neutronics analyses of a reference core with UO₂ fuel was performed to characterize parameters such as the radial neutron flux profile, the maximum to average flux ratio, the reactivity coefficient and critical boron concentration at beginning of life; which confirmed good performance in comparison to a standard UO₂ based pressurized water reactor.

Using this uranium oxide …

An Experimental Study Of Fabrication Temperature Effect On Aqueous Extrusion Freeform Fabrication, Jie Li

Masters Theses

"In order to understand the effect of fabrication temperature, a computer controlled 3-D gantry system was used to extrude aqueous alumina paste using Extrusion Freeform Fabrication. The system includes a temperature control subsystem that allows for fabrication of components below the paste's freezing temperature in the range of -10⁰C to -30⁰C and a hot plate with temperature in the range of 20⁰C to 80⁰C inside a room temperature chamber. Comparisons in terms of relative density, mechanical properties, part accuracy and minimum deposition angle were performed by Extrusion Freeform Fabrication at 40⁰C plate temperature inside a room temperature chamber and at …

Effect Of Polymer On Disproportionate Permeability Reduction To Gas And Water For Fractured Shales, Lingbo Liu

Masters Theses

"Large volumes of fracturing fluid are required in shale slickwater fracs, and a considerable amount of polymer friction reducer would remain in microfractures if the polymer has not been broken before gas production. It is of major interest to evaluate the effect of polymer on water/gas flow behavior in the microfractures of shale reservoirs. We fabricated six shale fracture models with different fracture widths and set up a core flooding apparatus to conduct brine/gas-injection experiments before and after polymer treatment. A method by which to calculate the residual resistance factor for gas (F_rr,gas) was defined. The experimental results …

Design And Implementation Of A 20 Ghz Ultra-Wide Bandwidth Channel Emulator For Differential High Speed Serial Data Links, Wei Qian

Masters Theses

"High speed serial link is now the dominant signal propagation design in various communication, computing and embedded applications. Emulation of such channels is important in signal integrity design and product testing, where full channel simulation is restricted due to the need for protection of intellectual property and frequent channel reconfiguration. This thesis introduces robust lossy material and FIR filter design methods that can be used for channel emulation to provide a solution under these restrictions. Based on the channel characterizations normally obtained in the frequency domain by vector network analysis, different emulation strategies and optimization techniques are utilized to emulate …

Spatial And Temporal Modulation Of Heat Source Using Light Modulator For Advanced Thermography, Arvindvivek Ravichandran

Masters Theses

"Thermography is a Non-Destructive Testing (NDT) method that has found increasing use in industry and research. It has the advantages of being non-contact and be able to interrogate a large surface simultaneously. Active thermography using flash lamps as heat source has been demonstrated for identifying blind holes and delamination in composites. Despite these advancements, active thermographic approach fails to defects like cracks. Under uniform illumination heat flow is predominantly 1D and can easily circumvent a narrow feature. This can be overcome by using a focused light/laser source onto the surface to impose a 3D heat flux. The disadvantage is that …

Experimental And Computational Evaluation Of Water Management And Performance Of A Bio-Inspired Pem Fuel Cell In Comparison To A Conventional Flow Field, Venkatanaga Bhaskar Prakash Saripella

Masters Theses

"Fuel cells are being increasingly used in various stationary and transportation power applications due to their higher energy efficiency and lower pollution. Flow field design in Proton Exchange Membrane (PEM) fuel cells is a major area of research for performance improvement. Bio-inspired flow field designs have significant potential for increased performance by effective distribution of reactants with better water management capabilities. In this study, a bio-inspired flow field design, formulated using Murray's law and mimicking a typical leaf venation pattern, is experimentally and computationally investigated in comparison to a conventional single serpentine design. Experiments are conducted using a special transparent …

Optimal Techno-Economic Sizing Of Wind/Solar/Battery Hybrid Microgrid System Using The Forever Power Method, Sami Hamed Alalwani

Masters Theses

"Advancement in power electronics, energy storage, control, and renewable energy sources has led to the use of integrated renewable energy sources in islanded microgrids (MG). Also, the uses of integrated renewable energy sources have become more technically applicable, more economically feasible, and more environmentally friendly than conventional sources. As a result, electrification of rural villages using renewable energy technologies has started to become widely adopted around the world. Since generating power from renewable energy sources is highly intermittent and difficult to predict, the use of proper energy storage technology is important to eliminate mismatches between the load demand and generation. …

Evaluation Of Nickel-Titanium Oxide-Niobium Pentoxide Metal Ceramic Composite As Interconnect For Solid Oxide Fuel Cell, Abhijith Budur

Masters Theses

"With increasing importance for clean energy, fuel cells have gained great significance in recent decades. Solid oxide fuel cells are easy to transport due to presence of solid electrolyte and also have requisite electrical properties,but have been obstructed by their limitation to be used at only temperatures greater than 600⁰C and less than 800⁰C. To construct a stack of cells, materials that are good electrical conductors and having necessary mechanical strengths at that temperatures are being considered as interconnects between the cells. Evaluation of Nickel-Titanium dioxide-Niobium pentoxide (NTN) as interconnect and comparison to Stainless Steel 441 alloy has been made …

Day Of The Week Effect In Returns And Volatility Of The S&P 500 Sector Indices, Juan Liu

Masters Theses

"Previous studies have shown that returns associated with the stock market or foreign exchange's futures show variations across the day of the week. On such study, that employs a modified GARCH model for estimation, shows that returns associated with the S&P 500 stock index is highest on Wednesday and lowest returns on Monday. The same study shows that volatility is highest on Fridays and lowest on Wednesdays. In this study we investigate if this day-of-the-week effect on returns and volatility is present in the different sectors that constitute the S&P 500 index. The data set used provides daily returns from …

The Development Of Near Field Probing Systems For Emc Near Field Visualization And Emi Source Localization, Hui He

Masters Theses

"The objectives of this research are to visualize the frequency dependent electromagnetic field distribution for electromagnetic compatibility (EMC) applications and the radiating source reconstruction on complex shaped electronic systems. This is achieved by combining near field probing with a system for automatically recording the probe position and orientation. Due to the complexity of the shape of the electronic systems of interest, and for utilizing the expertise of the user, the probe will be moved manually not robotically. Concurrently, the local near field will be recorded, associated with the location and displayed at near real time on the captured 3D geometry …

Comparative Study Of Three Types Of Inverters Based On The Output Total Harmonic Distortion, Paterrson Thomas

Masters Theses

"In this thesis, three cases of power electronic inverters are taken into consideration to analyze their performance in terms of total harmonic distortion in their output voltage and output current. Firstly, a single H-bridge inverter is simulated. Staircase switching technique is used to generate the gating pulses for the switches. Only one switch is made to toggle for every half cycle. The fundamental harmonic component of the desired output voltage is considered to be 120 V. Secondly, the same topology is used with a Bipolar PWM gating technique. The switching frequency of the carrier wave is 33*60 Hz. Thirdly, a …

Formation And Evolution Of Spinel In Aluminum Killed Calcium Treated Linepipe Steels, Obinna Adaba

Masters Theses

"Magnesium aluminate (Spinel) inclusions have been observed to cause hook crack in line pipe steels. These inclusions are typically formed during liquid steel processing at the ladle metallurgy furnace (LMF) and subsequently modified by calcium to form less harmful liquid inclusions. Unfortunately, spinel inclusions are still sometimes observed in samples taken from the tundish and coil after calcium treatment.

The formation and evolution of spinel inclusions during liquid steel processing at two industrial mini mills was investigated by analysis of lollipop samples taken at different stages of the steelmaking process. The effect of reoxidation on the formation of spinels after …

Analysis And Comparison Of Two High-Gain Interleaved Coupled-Inductor Boost Converters, Venkat Sai Prasad Gouribhatla

Masters Theses

"The main objective of this thesis is to compare and analyze two different high-gain dc-dc power electronic converters based on coupled inductors and capacitor-diode multiplier cells. The idea of these converters is to integrate the solar energy with a 400V DC microgrid. DC microgrids are more efficient, less expensive, and more reliable compared to AC microgrids. They also favor the integration of renewable energy sources. With the growing need for the utilization of more renewable sources of energy, photovoltaic panels have become one of the trending technologies which convert the energy from the sun to a useable electrical power. But …

Chemical Quantification With Ubiquitous Optoelectronic Devices, Altamash Mukhtar Fakki

Masters Theses

"Optical sensing in medical diagnosis and chemical analysis using optoelectronic devices is a growing technology since it offers many advantages including real time analysis, remote sensing capability and low cost approach. This thesis demonstrates that an optical sensing platform utilizing optical mouse, the ubiquitous optoelectronic computer peripheral, can be used in quantitative oxygen and pH analysis.

Work in the first paper includes the use of optical mice for fluorescence intensity imaging of commercial oxygen patch. This involves gray color intensity analysis of filtered images to determine the gaseous oxygen level.

In the second paper, the optical mice is used to …

Developing A Novel Methodolgy And Testbed For Fatigue Analysis Of Metal Specimens, Sai Aravind Palepu

Masters Theses

"A prototype of fatigue testing machine was built to determine the fatigue strength of materials. Proposed testing prototype was displacement controlled magnetic type bend fatigue testing machine. Designed prototype was tuned to operate at or near resonance of the specimen in order to amplify excitation displacement. Low maintenance i.e. zero wear of the parts was achieved, there were no moving components in the prototype machine. Crucial components used to build were: DC power supply, solenoid, Arduino UNO, supports and laser displacement sensor. DC source used to pass current through solenoid producing magnetic field; mosfet and Arduino generated square waves of …

The Bitcoin Blockchain As Financial Market Infrastructure: A Consideration Of Operational Risk, Angela Walch

Faculty Articles

“Blockchain” is the word on the street these days, with every significant financial institution experimenting with this new technology. Many say that this remarkable innovation could radically transform our financial system, eliminating the costs and inefficiencies that plague our existing financial infrastructures. Venture capital investments are pouring into blockchain startups, which are scrambling to disrupt the “quadrillion” dollar markets represented by existing financial market infrastructures. A debate rages over whether public, “permissionless” blockchains (like Bitcoin’s) or private, “permissioned” blockchains are more desirable.

Amidst this flurry of innovation and investment, this paper inquires into the suitability of the Bitcoin blockchain to …

Quasi-Subjectivity And Ethics In Non-Modernity, Justin T. Simpson

UNF Graduate Theses and Dissertations

The inspiration behind this philosophical endeavor is an ethical one: interested in what it means to flourish as a human being – how to live well and authentically. Similar to medicine and how the ability to prescribe the appropriate treatment depends on first making a diagnosis, the focus of this work will to be understand the human condition and the ways in which subjectivity, one’s sense of self, is constituted. Given the general dissatisfaction with the modern metaphysical picture of the world, which analyzes the world in terms of the mutually exclusive and completely separate categories of nature/objects and society/subjects, …

Analyzing The Effect Of Individual Factors And Organizational Context On Faculty Participation In Online Teaching, Deborah F. Miller

UNF Graduate Theses and Dissertations

This quantitative study analyzed the influence of individual factors and institutional context on faculty participation in online teaching at public higher education institutions in the United States. Through an ex post facto design, cause and effect relationships were explored using statistical analysis of a large national data set. Variables in the data set directly related to the areas of interest in this study included interest in teaching, student-centered pedagogy, autonomy and control, instructional support, and institutional climate. Factors related to interest in teaching and institutional reward were statistically significant (p

Campus Planners' Preferences For Residence Hall Project Delivery Methods, Paul E. Riel

UNF Graduate Theses and Dissertations

This research determined the preferred project delivery method utilized by campus planners when building student housing on a university campus. Four key performance indicators were also evaluated to determine if they influenced the campus planner to select a particular project delivery method. The four key performance indicators were: owner input, cost, safety, and on-time completion. Campus planners identified though the Society for Campus and University Planners (SCUP), were invited to participate in this survey research method. Five research questions were explored in this study. They were:

1. What is the preferred project delivery method (PDM) when building a residence hall …

Soldiers And Civil Rights: The Impact Of World War Ii On Jacksonville's African American Community, 1954-1960, Bryan Higham

UNF Graduate Theses and Dissertations

This research explores the role of returning African American veterans in the Civil Rights Movement in Jacksonville from 1945-1960. Black World War II veterans not only faced the typical challenges of returning to civilian life, but took up the fight for equality as well. While this work acknowledges existing arguments about black veterans in the Civil Rights Movement, it emphasizes and analyzes the importance of their military benefits and experience. The mechanizing revolution that occurred in the United States military in this era had a lasting impact on the soldiers fighting as well as communities back home, Jacksonville included. This …

Time Series Similarity Search In Distributed Key-Value Data Stores Using R-Trees, Aleksey Charapko

UNF Graduate Theses and Dissertations

Time series data are sequences of data points collected at certain time intervals. The advance in mobile and sensor technologies has led to rapid growth in the available amount of time series data. The ability to search large time series data sets can be extremely useful in many applications. In healthcare, a system monitoring vital signals can perform a search against the past data and identify possible health threatening conditions. In engineering, a system can analyze performances of complicated equipment and identify possible failure situations or needs of maintenance based on historical data.

Existing search methods for time series data …

Hadoop Based Data Intensive Computation On Iaas Cloud Platforms, Sruthi Vijayakumar

UNF Graduate Theses and Dissertations

Cloud computing is a relatively new form of computing which uses virtualized resources. It is dynamically scalable and is often provided as pay for use service over the Internet or Intranet or both. With increasing demand for data storage in the cloud, the study of data-intensive applications is becoming a primary focus. Data intensive applications are those which involve high CPU usage, processing large volumes of data typically in size of hundreds of gigabytes, terabytes or petabytes. The research in this thesis is focused on the Amazon’s Elastic Cloud Compute (EC2) and Amazon Elastic Map Reduce (EMR) using HiBench Hadoop …

Numerical Modeling And Analysis Of Tidal Variance And Marsh Productivity In The Guana Tolomato Matanzas National Estuarine Research Reserve, Florida, Amanda S. Tritinger

UNF Graduate Theses and Dissertations

Long term sustainability in salt marsh and mangroves is dependent on dominant species, such as Spartina alterniflora, to capture organic and inorganic sediment. The research analyzes that sustainability. This work demonstrates the prediction of hydrodynamics and biomass density of salt marsh to provide useful information for the planning and mitigation of sea-level rise impacts on marsh sustainability in the Guana Tolomato Matanzas National Estuarine Research Reserve (GTMNERR), Florida. An advanced circulation code was applied to simulate hydrodynamics (i.e., shallow water equations) in the GTMNERR. The model used a set of parameters and conditions based on the GTMNERR domain to predict …

Bottom Friction Assessment For Hydrodynamic Currents In The Lower St. Johns River, Henok Kefelegn Demissie

UNF Graduate Theses and Dissertations

A preexisting version of the 2D finite-element hydrodynamic model (code) ADCIRC was modified to enable assimilation of velocity data for calculation of longwave hydrodynamics of the lower St. Johns River. The data assimilation also enables model calibration and parameter estimation of directionally variant Manning’s n value using an anisotropic formulation of bottom roughness. This modified version of the ADCIRC code differs from the original ADCIRC model, as it introduces a module to provide evaluation of directional Manning’s roughness coefficient using observed velocity data for ebb and flood flow durations. The vector-based directional Manning’s n value is found by comparing the …

A Targeted Denial Of Service Attack On Data Caching Networks, Jeffrey B. Gouge

UNF Graduate Theses and Dissertations

With the rise of data exchange over the Internet, information-centric networks have become a popular research topic in computing. One major research topic on Information Centric Networks (ICN) is the use of data caching to increase network performance. However, research in the security concerns of data caching networks is lacking. One example of a data caching network can be seen using a Mobile Ad Hoc Network (MANET).

Recently, a study has shown that it is possible to infer military activity through cache behavior which is used as a basis for a formulated denial of service attack (DoS) that can be …

Sorting By Block Moves, Jici Huang

UNF Graduate Theses and Dissertations

The research in this thesis is focused on the problem of Block Sorting, which has applications in Computational Biology and in Optical Character Recognition (OCR). A block in a permutation is a maximal sequence of consecutive elements that are also consecutive in the identity permutation. BLOCK SORTING is the process of transforming an arbitrary permutation to the identity permutation through a sequence of block moves. Given an arbitrary permutation π and an integer m, the Block Sorting Problem, or the problem of deciding whether the transformation can be accomplished in at most m block moves has been shown to be …

Characterization Of A Biosynthetic Pathway Yielding Anticancer Natural Products From A Marine Bacterium, Elle D. James

UNF Graduate Theses and Dissertations

Natural products are bioactive secondary metabolites produced by living organisms and are prevalently utilized as pharmaceutical drugs. Marine adapted organisms are a promising source of new natural products possessing unique chemical structures and biological activities. By studying the biosynthetic pathways employed by living organisms to produce natural products, insights into new strategies to generate molecules to combat disease and overcome drug resistance may be gained. This thesis study aimed to uncover the biosynthetic pathway employed by a marine actinomycete, Nocardiopsis sp. CMB-M0232, to catalyze the assembly of the nocardioazines. These molecules are a group of 2,5-diketopiperazine natural products that feature …

Tapping Into The Social Capital Of African American Alumni Of Urban High Schools, Adrian Derrick Johnson

UNF Graduate Theses and Dissertations

The purpose of this study was to identify and understand how African American alumni of urban high schools perceived that they could best contribute to their former schools. Despite numerous improvement efforts for several decades, the academic performance of urban high school students has failed to keep pace with that of their suburban counterparts. This research was framed around the premise that the rich legacies and diverse cultural experiences of African American alumni of urban high schools could mitigate the outside factors that negatively impact student performance at urban schools. These funds of knowledge, as Moll and Amanti (2005) described …