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Dc, Rf, And Thermal Characterization Of High Electric Field Induced Degradation Mechanisms In Gan-On-Si High Electron Mobility Transistors, Matthew Anthony Bloom

Master's Theses

Gallium Nitride (GaN) high electron mobility transistors (HEMTs) are becoming increasingly popular in power amplifier systems as an alternative to bulkier vacuum tube technologies. GaN offers advantages over other III-V semiconductor heterostructures such as a large bandgap energy, a low dielectric constant, and a high critical breakdown field. The aforementioned qualities make GaN a prime candidate for high-power and radiation-hardened applications using a smaller form-factor. Several different types of semiconductor substrates have been considered for their thermal properties and cost-effectiveness, and Silicon (Si) has been of increasing interest due to a balance between both factors.

In this thesis, the DC, …

Hydrologic Modeling Of The San Joaquin Valley Watershed For Purposes Of Nitrate Analysis, Stephen Carl Clayton

Master's Theses

The San Joaquin Valley is regarded as one of the most productive agricultural regions in the world. This extensive agriculture has, however, caused extensive pollution of both ground water and surface water. This thesis develops a hydrologic model of the surface and ground waters of the San Joaquin Valley. Such modeling is useful in the development and implementation of water quality regulations such as Total Maximum Daily Loads (TMDLs). A properly validated watershed simulation model can supplement data collection and can account for watershed characteristics including topography, soils, climate, land cover, anthropogenic activities, as well as simulate watershed responses including …

Rfid Technology Selection And Economic Justification For Healthcare Asset Tracking, Tyler Robert Peabody, Tali Freed

Master's Theses

Although Radio Frequency Identification (RFID) and Real-Time Location System (RTLS) technologies for inventory tracking have been growing in popularity, the healthcare industry has been reluctant to adopt these technologies. One of the primary reasons for this lack of enthusiasm has been the risk associated with electromagnetic interference between RFID/RTLS systems and medical equipment functionality. The other reason has been the substantial cost and complexity of implementing RFID/RTLS in healthcare organizations. In this study, we show that there are several ways to safely install RFID/RTLS systems to improve the inventory management processes of hospitals and clinics. We then analyze the inventory …

Consumer Evaluation Of Low Sodium Mozzarella Cheese And Development Of A Novel Method For Evaluating Emotions, Lauren Alyse Collinsworth

Master's Theses

Mozzarella cheese is currently the highest consumed cheese in the United States. The popularity of mozzarella cheese is typically attributed to the high consumption rates of pizza cheese and string cheese; both of which are low moisture part skim (LMPS) mozzarella cheese. A single serving of LMPS mozzarella cheese contains approximately 8% of the daily value (DV) for sodium, a mineral which is currently consumed in excess among most Americans. On average, one in three Americans has hypertension. This condition is strongly associated with excessive sodium intake, and it is a leading risk factor for cardiovascular disease and stroke in …

Cloth Filter For Disaster Relief Water Treatment, Shasta Le'ja Billings

Master's Theses

Relief organizations and governments strive to provide safe drinking water to natural disaster survivors as quickly as possible. However, drinking water is typically provided either as bottled water or via mobile water treatment equipment, both of which can be difficult or expensive to transport rapidly into disaster zones. An alternative is the waterbag point-of-use treatment device developed at Cal Poly that allows survivors to produce safe drinking water from contaminated local sources. The waterbag is a 10-L bladder designed for use with Procter & Gamble Purifier of Water (PŪR^®) sachets, which contain coagulant and chlorine compounds. Following treatment …

Bacterial Growth On Metal And Non-Metal Surfaces In A Static Bioreactor, Rolan Yuk Loong Liong

Master's Theses

Research was conducted to observe bacterial growth on the surface of metals in a static bioreactor. Metal and non-metal samples were subjected to bacterial exposure (1 day and 9 days). The metal samples were surface treated prior to bacterial exposure. The microstructures of the surface treated samples were analyzed by optical microscopy. After exposure, the microstructures of the samples were analyzed by scanning electron microscopy (SEM). The analysis suggested that microbial attachment on the surface was related to the underlying microstructure of steel. The preferential attachment of microbes could potentially be influenced by cathodic and anodic regions created by the …

Monitoring Mdpc-23 Odontoblast-Like Cell Proliferation Using Cell Count And Dna Content Methods, Marina Funtik D.M.D.

Master's Theses

There is growing interest in the development of an engineering process by which dentin stem/progenitor cells can predictably proliferate, differentiate and produce mineralization nodules in cell culture. The engineering of 3D scaffolds could then be used to aid in proliferation and differentiation of these progenitor cells to aid in regeneration of the pulp/dentin complex in vivo.

In the present study, the goal was to characterize the MDPC-23 cell line and its behavior during proliferation. The cells in culture reach high numbers upon reaching confluence. When cells are growing in multilayers, as will occur in planned dentin regeneration experiments, it …

Material Characterization Of Ultra-High Performance Fiber Reinforced Concrete At Elevated Temperatures, Richard T. Way

Master's Theses

With the recent development of Ultra High Performance Fiber Reinforced Concrete (UHPFRC), there has been limited investigation into the mechanical and material properties of this composite at elevated temperatures. At elevated temperatures concrete is shown to undergo several material changes which affect the residual mechanical properties. Additionally, fast heating rates are known to cause a phenomenon called explosive spalling. This research investigates the effect of high temperature on the residual mechanical properties and chemical degradation of two types of UHPFRC. This was accomplished by casting and testing two different UHPFRC mixes and exposing them to elevated temperatures at two rates …

Material Characterization And The Effects Of Moisture And Drying On Injection Molded Torlon 5030, Michael R. Di Re

Master's Theses

The effects of water absorption and drying were studied on injection molded Torlon 5030, a high performance thermoplastic fabricated by Solvay Specialty Polymers. Torlon 5030 contains 30% by weight glass fibers in a polyamide-imide base resin. The objective behind this work was to test and better define relevant properties for industrial applications using this material. While the material design guide offers information on many mechanical properties including tensile, fatigue, and creep data; there is little to no publicly published data on the effects of water absorption and any subsequent drying of Torlon 5030. Blistering was also studied. With exposure to …

Microkinetic Modeling And Analysis Of Ethanol Partial Oxidation And Reforming Reaction Pathways On Platinum At Short Contact Times, Maura A. Koehle

Master's Theses

No abstract provided.

Exploring The Efficacy Of The Community Organization Health Model As A Tool For Evaluating Sport-For-Development Programs: A Qualitative Content Analysis Of Three Model Programs, Lauren Faye Denman

Master's Theses

The HIV/AIDS pandemic is currently one of the most pressing world-wide concerns regarding the health and well-being of our global population. Due to the lack of a cure, recent efforts have focused on prevention measures for the disease. HIV prevention, particularly with the youth population, has spawned creative programs, such as the use of sport as an educational tool to equip youth with the skills to avoid contracting HIV. Due to the potent effect sport-for-development efforts exhibit on both individual and cultural level change, it can be assumed that HIV prevention sport-for-development programs are worth maintaining. Within the use of …

Structural Health Monitoring For In-Service Highway Bridges Using Smart Sensors, Sushil Dahal

Master's Theses

With the rapid development of electrical circuits, Microelectromechanical system (MEMS) and network technology, wireless smart sensor networks (WSSN) have shown significant potential for replacing existing wired Structural health monitoring (SHM) systems due to their cost effectiveness and versatility. A few structural systems have been monitored using WSSN measuring acceleration, temperature, wind speed, humidity; however, a multi-scale sensing device which has the capability to measure the displacement has not been yet developed. In this research, a new high accuracy displacement sensing system has been developed combining a high resolution analog displacement sensor and MEMS-based wireless microprocessor platform. The developed multi-scale sensing …

Optimizing Propagation Of Ceanothus Americanus L., (New Jersey Tea), Corylus Cornuta Marsh. (Beaked Filbert), Lonicera Canadensis Bartr. (American Fly Honeysuckle), And Viburnum Acerifolium L. (Mapleleaf Viburnum) By Softwood Stem Cuttings, Julia A. Cartabiano

Master's Theses

No abstract provided.

Automated Point-Of-Care Image Processing Methodology For The Diagnosis Of Malaria, Michael B. Jorgensen

Master's Theses

Malaria has profoundly influenced human history for over four thousand years and despite numerous attempts at eradication, the prevention, diagnosis, and treatment of malaria have been largely ineffective. More than five hundred million people are affected by malaria every year resulting in over one million deaths. Drug resistance development by the parasite has diminished the effectiveness of numerous treatment options due, in part, to overtreatment of negative patients based on insufficient clinical algorithms and diagnostic methods. The goal of this research was to develop an image analysis algorithm to diagnose malaria with a high degree of sensitivity and specificity in …

Preparation Of Organofluorine Compounds: Exploring Mono-, Di-, And Tri-Fluorination, Diandra M. Rudzinski

Master's Theses

Organofluorine compounds exhibit biological activity and have advantageous properties for drug design. Natural occurring fluorinated molecules are rare, demanding new synthetic methods for their preparation. A novel route to access trifluoromethyl ketones from Weinreb amide precursors is discussed. This is the first documented method for the use of the Ruppert-Prakash reagent, (trifluoromethyl)trimethylsilane, for the production of trifluoromethyl ketones from amide starting materials. This method is tolerant of aryl and alkyl substrates exhibited by their moderate to excellent yields. A discussion of the unusual reactivity of these amides, their selectivity for mono-trifluoromethylation, and other mono-, and di-fluorination attempts are reported.

Multiplatform Analysis Seismic Evaluation Of A Non-Seismically Detailed Nonlinear Rc Structure Retrofitted With Magneto-Rheological Dampers, Eric R. Lovejoy

Master's Theses

In prior research, the MR damper's dynamic characteristics are typically modeled in the MATLAB/Simulink environment. Creating a structural model with nonlinear material properties, however, may be challenging in the MATLAB/Simulink environment without approximating the material behavior and neglecting effects such as P-∆ or panel zone behavior. More behaviorally accurate models of these structures can be produced using nonlinear finite element analysis tools such as Abaqus, OpenSees or ZuesNL. These analysis tools, however, are not traditionally used to model the complex nonlinear and controllable behavior of MR dampers, nor their associated control algorithms. One solution is to facilitate communication between these …

The Effect Of Statins On Resting Blood Pressure And The Peak Blood Pressure Response To A Graded Exercise Stress Test, Marianne L. Mentch

Master's Theses

No abstract provided.

The Role Of Dax-1 In Regulating Pluripotency In Mouse Embryonic Stem Cells, Anthony Torres

Master's Theses

The orphan receptor Dax-1 is highly expressed in pluripotent embryonic stem (ES) cells and shows a correlative reduction in expression as these cells differentiate. While it is known that Dax-1 is expressed in pluripotent mouse ES cells, the precise function of Dax-1 in these cells is not as well understood. Recent studies employing RNA interference (RNAi) to specifically reduce the expression of the Dax-1 gene in mouse ES cells found that upon the knock down of Dax-1, ES cells differentiated. These findings indicate that Dax-1 functions in a novel role in the maintenance of a relatively undifferentiated state in ES …

Measurement Invariance Of Assessment Center Ratings: Consistency Of Dimensional Constructs Across Exercises, Jin Lee

Master's Theses

The criterion-related validity of assessment centers (ACs) has been consistently supported. However, there has been an ongoing debate about AC construct validity in regard to low dimension variance and overriding exercise variance. Many studies that showed weak dimension effects in ACs have been based on the multitrait-multimethod (MTMM) framework which posits cross-situational variance as error and all capability dimensions can be equally represented from different exercises. The goal of this study is to introduce a measurement invariance (MI) framework for evaluating the construct validity of AC dimensions. Specifically, MI analysis was used to test whether the construct meaning of AC …

A Case Study Of Sex Trafficking In Romania, Iulia Badea Caramello

Master's Theses

Romania is undergoing a severe crisis. The country is confronted with a transnational issue of dramatic proportions. Romania has become what experts in the sex trafficking field call “a global center for human trafficking” (Batstone, Romania a Global Center for Human Trafficking, 2011, February 17th). It is a source, transit, and destination country for women, children, and even men subjected to sex trafficking. Romania is one of the biggest exporters of human flesh to Western European and Middle Eastern societies.

This research paper will analyze the historical context of modern-day slavery in Romania as well as the economic background and …

Investigation Of Astm E 238 Bearing Pin Properties For Various Aerospace Alloys, Trevor J. Lee

Master's Theses

Aircraft are often designed with numbers determined by testing in a lab, rather than by repeatedly building prototypes. These lab tests conform to testing specifications so that the numbers can be compared between manufacturers, suppliers, and lab technicians. One such specification is ASTM specification E238 – 84(08), and it is used to determine important properties of a bearing pin joint like hinges, bolt holes, and rivet joints. The properties determined from this fastener-through-plate method are bearing strength, bearing yield strength, and bearing stiffness.

Adhering to the methods outlined in ASTM E238, a study was performed, looking at the effects that …

The Role Of Self-Esteem, Perceived Social Support, And Coping Strategy In The Escalation Of Depressive Symptomatology During The First Year Of College, Catherine Lee

Master's Theses

The first year of college is a significant life transition that can be a particularly stressful experience, which may lead to the development or exacerbation of depressive symptoms. Due to the considerable negative outcomes that are associated with depressive symptoms across the lifespan, it is important to understand the mechanisms and pathways through which such symptoms arise. This prospective study examines how self-esteem, perceived social support, and coping strategies are associated with the development of depressive symptoms during the transition to college. The findings of this longitudinal study indicate that self-esteem may affect both perceived social support and disengagement coping …

Titan I Propulsion System Modeling And Possible Performance Improvements, Oreste Giusti

Master's Theses

This thesis features the Titan I propulsion systems and offers data-supported suggestions for improvements to increase performance. The original propulsion systems were modeled both graphically in CAD and via equations. Due to the limited availability of published information, it was necessary to create a more detailed, secondary set of models. Various engineering equations--pertinent to rocket engine design--were implemented in order to generate the desired extra detail. This study describes how these new models were then imported into the ESI CFD Suite. Various parameters are applied to these imported models as inputs that include, for example, bi-propellant combinations, pressure, temperatures, and …

Effectiveness Of Peer Mentoring In First-Year Program Classrooms, Katherine Casey

Master's Theses

First-year programs (FYPs) for college students offer extended orientation to campus resources and provide first-time freshmen with essential skills for academic success, and many believe that the effectiveness of FYPs increases with the presence of peer mentors. The present study measured the added effectiveness of peer mentoring in FYP classrooms with knowledge of campus resources as a dependent measure. Ninety one first-year students in nine sections of FYP classes participated in this quasi-experimental study. Seven of the classes had peer mentors (n = 70), and the two control classes (n = 21) did not have peer mentors in the classroom. …

The Effect Of Sensor Mass, Sensor Location, And Delamination Location Of Different Composite Structures Under Dynamic Loading, Albert Darien Liu

Master's Theses

This study investigated the effect of sensor mass, sensor location, and delamination location of different composite structures under dynamic loading. The study pertains to research of the use of accelerometers and dynamic response as a cost-effective and reliable method of structural health monitoring in composite structures. The composite structures in this research included carbon fiber plates, carbon fiber-foam sandwich panels, and carbon-fiber honeycomb sandwich panels. The composite structures were manufactured with the use of a Tetrahedron MTP-8 heat press. All work was conducted in the Cal Poly Aerospace Structures/Composites Laboratory. Initial delaminations were placed at several locations along the specimen, …

The Lifestyle And Prevalence Of Vegetarianism In Seventh-Day Adventist Hispanics, Maribel Hidalgo

Master's Theses

Problem. Hispanics are disproportionately affected by chronic diseases and are a growing and significant population. There is minimal research regarding the lifestyle of the Seventh-day Adventists (SDA) among the Hispanic community. The purpose of this cross-sectional descriptive study was to ascertain the lifestyle, health status, eating and physical activity habits of the SDA Hispanics from part of the Midwest. -- Method. An anonymous survey was distributed in person to a convenience sample of 150 participants 18 years or older in the SDA Hispanic churches of Berrien Springs, Grand Rapids, Chicago, and Indianapolis. The survey was divided into five sections: demographics, …

Perceptions Of Psychology Among Seminary And Biology Students At Andrews University, Sandro Moraes

Master's Theses

Problem. Both pastors and biologists frequently interact with individuals. These contacts often involve conversations that deal with an individual’s feelings, behaviors, and the relationship between mind and body. Thus, how seminarians and biologists perceive psychology will greatly affect such interactions. Therefore it is important to know how both professionals perceive psychology. This is not all that different from the research biologists perform as they learn about the brain. Because of the interrelatedness between these two professions, what are the perceptions of psychology among seminary and biology students at Andrews University? -- Method. The data gathered from the responses of biology …

Exercise Motivators And Exercise Causality Among Andrews University Students: A Correlational Study, Anna T. Piskozub

Master's Theses

Purpose of the Study. A healthy, fit body and well-developed mind have been known to be very effective in helping students succeed academically, socially, behaviorally, and emotionally. Understanding what motivators influence students in exercise participation, and how such motivators may influence choice in undertaking physical activities can be valuable information when planning college physical fitness courses and wellness activities. Further, it may reverse the trend of the findings that Andrews University students’ fitness declines while being in college as measured by 10 years of Microfit aggregated data. The purpose of this study was to identify the most important exercise motivators …

Evaluating Hypotheses That Explain Non-Continuous Responses To Syllable Periods ("Skipping") During Phonotaxis By Female Acheta Domesticus, Tori Joy Steely

Master's Theses

One way to classify female cricket phonotactic response is as "non-skipping" or "skipping." "Skipping" is defined as crickets that respond to a non-continuous range of calling songs. This investigation evaluates the temporal aspects of typical phonotactic protocols and attempts to determine if "skipping" is due to a filtering mechanism or if "skipping" is an artifact of testing protocol. Rather than a notch filter or testing parameters inhibiting a phonotactic response to a syllable period within the range of a band pass filter, I hypothesize that "skipping" occurs as a result of the probabilistic nature of phonotaxis.

The Role Of At Epistemic Community In Haitian Education Reform Post Earthquake 2010, Joy Okeefe

Master's Theses

This is a study of the role of an epistemic community involved in the policymaking of education reform in Haiti after the devastating earthquake of 2010. It uses Peter M. Haas' (1992) framework as a theoretical lens. According to Haas, epistemic communities are conceptualized as "a network of professionals with recognized expertise and competence in a particular domain and an authoritative claim to policy relevant knowledge within a domain or issue area" (3). The epistemic communities involved in the policymaking of the current education reforms specifically related to privatization in Haiti are identified and analyzed through the content analysis of …