Digital Commons Network^™

Strength Evaluation And Transportation Behavior Of Preformed Particle Gel Using Screens And Tubes, Rajesh Sarma Challa

Masters Theses

"This research included a series of experiments, using screen models to evaluate the strength of swollen gel particles. It also includes the study of PPG propagation and extrusion behavior through tubes of various internal diameters. The effect of the particle gel swelling ratio (depending on brine concentration), flow rate; and mesh size on the gel injection pressure and injectivity were studied. The results show that gel injection pressure depends primarily on the swelling ratio and the mesh size. However, the injection pressure does not increase significantly with injection rates, behavior consistent with the real-time injection pressure and injection rate change …

Excitation Of Whispering Gallery Modes In Glass Microspheres Using Optical Fiber Couplers, Sudha Sneha Devarakonda

Masters Theses

"This research is a study conducted on the excitation of whispering gallery modes (WGM) in small micron-scale glass spheres. Optical WGM may be represented by a light wave that propagates along the surface of the sphere and reaches back itself in phase at specific wavelengths. Due to this, very high intensities of light with narrow line widths circulate in the microspheres contributing to high Q factor. The evanescent field of an optical waveguide is used to resonantly stimulate the WGM.

The WGM excitation in fused silica spheres was demonstrated in the laboratory with 60% coupling efficiency. Tapered optical fibers were …

Mechanical Properties And Microstructure Study For Direct Metal Deposition Of 316l Stainless Steel, Tian Fu

Masters Theses

"Direct metal deposition or laser cladding is a process capable of producing fully dense and net shape metal products and this process could be used on coating metal components in various engineering applications. This process has fast heating and cooling rates which can improve the surface hardness and provide excellent adhesion through metallurgical bond between coating material and substrate. This paper evaluated the laser deposited 316L stainless steel coating on 4340 steel, which is widely used for aircraft landing gear applications. The microstructure, micro-hardness and quantitative EDS were explored to verify the coating properties. The desired homogeneous microstructure and high …

Calibration Of Resistance Factors For Axial Capacity Of Driven Pile Into Missouri Soil, Mulugeta Abay Kebede

Masters Theses

"Over the past two decades the load resistance factor design (LRFD) has been accepted by the American Association for Transportation and Highway Officials (AASHTO) for the design of bridges. This approach is now gaining widespread popularity in the United States for substructure bridge design, including the design of driven pile foundations, as the states calibrate the geotechnical resistance factors for local geological conditions and practices. This study presents the geotechnical resistance factors calibrated for axially driven pile using the first-order reliability method (FORM) for the target reliability index of 2.33 and 3.0 based on 64 end-of-drives (EOD) and 22 beginning-of …

Establishing Workload Limitations For Application In Human Systems Integration, Muhammet Servet Gulum

Masters Theses

"As the amount of technology involved in the typical workplace increases and standard operational procedures become increasingly sophisticated the danger of overloading an operator's mental resources is increasing. As much as these technological developments help operators with daily tasks, for example by providing information via monitors and wireless headsets; it also increased the mental workload due to the bombardment of information. Mental workload is commonly associated with information processing tasks, limits. With all the extra information inputs it is difficult to set limits where excessive information becomes dangerous. The workload optimization is critical as it directly affects system performance and …

Evaluation Of Alternative Methods For Surface Preparation And Deposition Of Cerium-Based Conversion Coatings On Aluminum Alloys, William J. Gammill

Masters Theses

"This thesis investigates alternative surface preparation and deposition methods for cerium-based conversion coatings (CeCC) on high strength aluminum alloys. Cerium-based conversion coatings are being investigated as a more environmentally friendly replacement for chromium-based conversion coatings. Currently, the alloys are immersed in strong alkaline and acidic solutions to prepare the aluminum surfaces for conversion coating, in which immersion may not be suitable for all situations. Alternatives to this method were investigated, including wipe application of solution, ultrasonic processing in deionized water, and abrasive blasting with alumina. AI 7075-T6 test panels were prepared using each of these methods and compared to a …

Sintering And Microstructural Effects On Mechanical Properties Of Zirconium Carbide-Tungsten Cermets, Melissa M. Giles Craft

Masters Theses

"Zirconium carbide-tungsten cermets were prepared by in situ reaction sintering a mixture of zirconia and tungsten carbide. Tungsten is a refractory metal with a melting point of 3422⁰C; however, its mechanical strength decreases significantly with increasing temperature. One approach to improve the elevated temperature strength is to add ceramic particulates to the matrix. Zirconia and tungsten carbide were compacted and then reacted and sintered in a single step by heating to 2050⁰C. The resulting stoichiometric zirconium carbide-tungsten cermet had a relative density greater than 96%. Cermets with two different grain sizes were produced by altering the final sintering temperature. Sintering …

"In Situ" Printed Circuit Board Material Extraction Procedure With Conductor Surface Roughness Study, Amendra Koul

Masters Theses

"Analysis of printed circuit board (PCB) behavior in a wide frequency range from tens MHz to at least 40 GHz is very important for modern high-speed digital design and assuring for signal integrity (SI). this analysis includes preliminary evaluation of per-unit-length parameters of the PCB transmission line and transmission line characteristics, such as propagation and attenuation constants, and also extraction of these parameters from measurements on real test vehicles. This thesis describes an impedance calculator tool, which can substantially speed up PCB design, and the second topic considered in this work is characterization of dielectric parameters of substrates of printed …

Performance Evaluation Of A Novel Diesel Fuel Air Separation And Filtration System For An Indirect Injection Diesel Engine, Michael Ray Hess

Masters Theses

"The objective of this research was to evaluate an air/fuel separation system known as a Fuel Preporator. The device's efficacy was determined by studying the effect of air entrainment on engine performance and fuel consumption of a General Motors 6.5 L naturally aspirated indirect injection (IDI) diesel engine. A test bed was developed to accommodate the test engine and test methods were adapted from federal regulations for steady-state engine testing (40 CFR 89 Subpart E). Cases of 0%, 5%, 10%, and 20% volumetric air entrainment were investigated for engine operation with and without the Fuel Preporator. Key measured engine performance …

Innovative Concrete Bridging Systems For Pedestrian Bridges: Implementation And Monitoring, Kurt Edward Bloch

Masters Theses

"Two precast, prestressed pedestrian bridges were designed for rapid construction in Rolla, MO, utilizing high-strength concrete (HSC) and high-strength self-consolidating concrete (HS-SCC) with a target 28 day compressive strength of 68.9 MPa (10,000 psi) and release compressive strength of 24.1 MPa (3,500 psi). In addition, a glass fiber reinforced polymer (GFRP) bar reinforced deck panel system was utilized in one of the two deck panels on each bridge.

Material properties were tested for compression, elastic modulus, modulus of rupture, splitting tensile strength, creep, and shrinkage following ASTM standards. Instrumentation systems within the spandrel beams and precast deck panels were implemented …

Field Analysis Of Photovoltaic Ultracapacitor Energy Storage System, Jenna Vujic

Masters Theses

"In the field of innovative power sources, photovoltaics are playing an important role as a clean energy source. Because performance is dependent on instantaneous weather conditions, all stand-alone photovoltaic (PV) systems require an energy storage device. Batteries are not suitable for PV source applications due to depth of discharge restrictions, maintenance requirements and minimal power density availability. However, ultracapacitors (UCAPs) have a high power density, require little maintenance, and can be used in sequence with a dc-dc converter to maintain power output at an increased depth of discharge. This paper describes a PV-UCAP power system used to collect and compare …

Speech Intelligibility From Image Processing, Andrew Hines, Naomi Harte

Articles

Hearing loss research has traditionally been based on perceptual criteria, speech intelligibility and threshold levels. The development of computational models of the auditory-periphery has allowed experimentation via simulation to provide quantitative, repeatable results at a more granular level than would be practical with clinical research on human subjects.

Water Analysis For Emerging Environmental Contaminants, Xiaoliang Cheng

Masters Theses

"The presence of emerging environmental contaminants in water bodies used either as drinking water or for recreational purpose has received considerable attention in the recent years. The emerging environmental contaminants can be defined as a wide range of chemicals that have been determined in the environment which may present serious health risks for humans. The occurrence of these contaminants indicate that both household and industrial chemicals have been introduced to water resources, a wide variety of chemicals, such as disinfection byproducts, pharmaceutical and personal care products and so on, have been detected at cetiain levels in either water bodies or …

Automation Of Cad Model Based Assembly Simulations Using Motion Capture, Anup Madhav Vader

Masters Theses

"The manufacturing industry often uses text and video as a supplement for worker training procedures. Unfortunately, text is often difficult to follow and video lends itself to occlusion issues. CAD based animations of assembly operations can overcome these shortcomings while offering greater potential for operations analysis and simulation flexibility. However, creating such CAD based training simulations manually is a time intensive task and many a times fail to reveal the practical assembly issues faced in the real world. Thus, it is highly beneficial to be able to automate these simulations using motion capture from a physical environment. This thesis research …

Development Of Novel Backscatter Communication Systems Using A Multi-Hop Framework And Distributed Beamforming, Vikram Reddy Surendra

Masters Theses

"The goal of this thesis it to develop a wireless networking framework for battery-free devices based on passive, backscatter communication. In contrast to traditional, active communication systems, where the radio signal has to be generated using large amount of energy from batteries, the passive systems reflect the RF signal. The information is encoded by modulating the reflected signal, which consumes significantly less energy than active transmission. The existing passive, backscatter systems have limited communication capabilities. For example, the Radio Frequency Identification (RFID) systems support short-distance, direct communication between active reader and passive tags. The communication range is limited due to …

Design And Critical Performance Evaluation Of Horizontal Axis Hydrokinetic Turbines, Suchi Subhra Mukherji

Masters Theses

"The current work discusses the hydrodynamic performance of horizontal axis hydrokinetic turbines (HAHkT) under different turbine geometries and flow conditions. Hydrokinetic turbines are a class of zero-head hydropower systems which utilize kinetic energy of flowing water to drive a generator. However, such turbines often suffer from low-efficiency. A detailed computational fluid dynamics study was performed using a low-order k-[omega] SST (Shear Stress Transport) turbulence model to examine the effect of each of tip-speed ratio, solidity, angle of attack and number of blades on the performance of small HAHkTs with a power capacity of 10 kW. The numerical models (both two-dimensional …

Relationships Between Life Satisfaction, Symptoms Of Adhd, And Associated Outcomes In Middle School Students, Lisa Paige Bateman

USF Tampa Graduate Theses and Dissertations

Given increased evidence related to the importance of fostering life satisfaction in the overall population (Diener & Diener, 1996), as well as recent suggestions regarding the importance of increasing positive academic and social outcomes for youth with ADHD (DuPaul, 2007), it is important to gain a clearer understanding of how life satisfaction may be related to ADHD symptoms. Although research has examined the relationship between life satisfaction and externalizing behavior (Suldo & Huebner, 2004a), research on the relationship between life satisfaction and ADHD is currently limited. This study examined if levels of ADHD symptoms predicted reports of life satisfaction in …

Magnetocaloric Effect In Thin Films And Heterostructures, Christopher Bauer

USF Tampa Graduate Theses and Dissertations

The goals of this work are the optimization of the magnetocaloric effect in Gadolinium thin film structures. We approach this issue from two directions, that of process optimization and of interface effects. Past results showed Gd₂O₃ in our Gadolinium thin films, and the presence of such oxide seemed to grow with the temperature at which the film was grown or annealed. Comparison of samples grown without chamber gettering to those that were gettered show differences in their structural and magnetic properties, and we conclude that gettering is an effective step in enhancing the quality of Gd thin …

Weder Bürger Noch Mensch: Gefangener Der Medien Und Des Rechtsstaats Gekoppelte Entmenschlichung Mit Radikalisierung Zwei Auffassungen Heinrich Bölls Die Verlorene Ehre Der Katharina Blum Oder: Wie Gewalt Entstehen Und Wohin Sie Führen Kann, Tyler Robert Russ

Dissertations and Theses

In his 1974 novella The lost Honor of Katharina Blum Heinrich Böll argues for the constitutional guarantee of presumption of innocence. He states that this principle is violated when defamatory media headlines make unwarranted accusations against a private citizen destroying their reputation as part of a targeted smear campaign. The novella characterizes such intentional campaigns as both criminalizing and dehumanizing. Böll argues that the government should influence the press to conform to the limits implied in the institution of freedom of press. He shows the helplessness of a private citizen under attack from a smear campaign …

Regional Integration In East Asia, Amaleia E. Kolovos

Dissertations and Theses

Regional integration is not a new phenomenon but has become an increasingly important topic of political research with the continued expansion of the European Union as well as an increased number of regional organizations around the globe. This paper will seek to use both Europe and East Asia as illustrations in order to better comprehend the driving forces behind integration as well as why some regions are further integrated than others. The purpose of this research is to achieve a better understanding of what causes regional integration in hopes of developing a more inclusive theory. More specifically, it aims to …

Spousal Crossover Effects Of Job Demands On Health, Rachel Jane Daniels

Dissertations and Theses

The primary goal of this dissertation was to examine the crossover effects of an individual's job demands on the perceived health of the spouse. Using a sample of grocery store employees and their partners, crossover relationships were examined for 90 dyads using Structural Equation Modeling. Although the models had good fit, the proposed direct crossover relationships of job demands on health were not supported. Job demands of one partner did not significantly predict health outcomes in the other partner; although follow-up analyses found significant crossover of women's job satisfaction on men's mental health scores. An additional crossover relationship was supported …

Local Food And Land-Use In Washington County, Oregon, Joshua James Cousins

Dissertations and Theses

Local food networks are often defined as presenting a variety of alternative food production, consumption, and distribution practices to the conventional food system such as community-supported-agriculture, farmers markets, and community gardens. Local food initiatives are commonly proposed as a model for the future of sustainable agriculture, and in the region of Portland, Oregon the abundance of such alternative venues results from the area's natural surroundings and smart planning. The region is host to 39 farmers markets and Portland is often hailed as one of the country's most sustainable cities. This study examines the role of local food networks in preserving …

Design Of Regular Reversible Quantum Circuits, Dipal Shah

Dissertations and Theses

The computing power in terms of speed and capacity of today's digital computers has improved tremendously in the last decade. This improvement came mainly due to a revolution in manufacturing technology by developing the ability to manufacture smaller devices and by integrating more devices on a single die. Further development of the current technology will be restricted by physical limits since it won't be possible to shrink devices beyond a certain size. Eventually, classical electrical circuits will encounter the barrier of quantum mechanics. The laws of quantum mechanics can be used for building computing systems that work on the principles …

Women And Resistance In The African Diaspora, With Special Focus On The Caribbean (Trinidad And Tobago) And U.S.A., Clare Johnson Washington

Dissertations and Theses

American history has celebrated the involvement of black women in the "underground railroad," but little is said about women's everyday resistance to the institutional constraints and abuses of slavery. Many Americans have probably heard of and know about Harriet Tubman and Sojourner Truth -- two very prominent black female resistance leaders and abolitionists -- but this thesis addresses the lives of some of the less-celebrated and lesser-known (more obscure) women; part of the focus is on the common tasks, relationships, burdens, and leadership roles of these very brave enslaved women.

Resistance history in the Caribbean and Americas in its various …

Quasi Steady Capillary Corner Flow, John Alex Baker

Dissertations and Theses

It is possible to drain slender containers filled with wetting liquids via capillary flows along the interior corners of the container. Usually the well established equations governing such flows demand numerical techniques. In the case of container draining unique boundary conditions resulting from local section geometry allow for a quasi-steady assumption and in turn permit analytical solutions. The quasi-steady assumption may also be employed for certain problems in which the corner flows cause passive capillary migration of the fluid within the container. The analytic solutions are useful because of the ease in which geometric effects may be observed. Container draining …

Exclude Evidence You Exclude Justice’? A Critical Evaluation Of Israel’S Exclusionary Rule After Issacharov, Binyamin Blum

Faculty Scholarship

No abstract provided.

A World Of Possibilities: Multimodalities, Collaboration And Equity In The Composition Classroom, Anicca Cox

Cal Poly Humboldt theses and projects

In this unbound project titled, A World of Possibilities: Multimodalities, Collaboration and Equality in the Composition Classroom I have shown some of the advantages of using multimodal writing instruction. Multimodal writing instruction uses a variety of methods that move beyond written text by incorporating visual, aural, cinematic or textual features together. This project focused on presenting multimodal approaches in the context of multiliteracies in order to achieve social justice and inclusion. The project is centered on collaborative methods and examines specific multimodalities to present possible techniques for incorporating these methods in a composition classroom. The goal of the project is …

Sentencing Reform In California, Aaron J. Rappaport

Faculty Scholarship

No abstract provided.

Above All Else Stop Digging: Local Government Law As A (Partial) Cause Of (And Solution To) The Current Housing Crisis, Darien Shanske

Faculty Scholarship

No abstract provided.

Engquist And The Erosion Of The Equal Protection Clause: An Attempt To Stop The Creep Of Irrational Dicta, Darien Shanske

Faculty Scholarship

No abstract provided.