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Implementation Of Physiologic Flow Conditions In A Blood Vessel Mimic Bioreactor System For The Evaluation Of Intravascular Devices, Marc Cody Dawson

Master's Theses

The prevalence and devastating nature of cardiovascular diseases has led to many advancements in the therapies used to treat the millions of patients that suffer as a result of these conditions. As coronary artery disease (CAD) is the most common of these cardiovascular conditions, it is a major focus of research among the medical industry. Although lifestyle changes and drug therapies can treat early CAD, more advanced cases often require more definitive interventions. In conjunction with angioplasty, stenting of an occluded vessel has shown significant success in preventing restenosis. However, as with nearly every therapeutic process in the medical field, …

Target Tracking Using Various Filters In Synthetic Aperture Radar Data And Imagery, Jessica L. Kiefer

Master's Theses

This thesis explores the use and accuracy of several discrete-time image filters for the purpose of target tracking in Synthetic Aperture Radar imagery. Both extended targets and point targets are used for tracking, showing the need for different types of filters for each target type.

Monte Carlo analysis is performed on the results of the extended target filter results to determine the absolute mean-squared error between the filter prediction of the target centroid and the actual location of the target centroid. Two different filters were chosen for the extended target: Kalman and H Infinity.

Both the Kalman and H Infinity …

City Of South Lake Tahoe Subdivision Ordinance: An Opportunity For Smart Growth, Sustainability, And Application Streamlining, Hilary Kay Hodges

Master's Theses

The City of South Lake Tahoe currently does not have an adopted subdivision ordinance. This has caused confusion about the approval process and regulatory requirements as well as delays in application processing. This Professional Project will explore the opportunity for the City to adopt a subdivision ordinance that would provide direction for subdivision design and approval and further the City’s smart growth and sustainability policies. However, there would need to be careful consideration for the potential increase in costs that are associated with additional fees or off-site improvement requirements. The Subdivision Ordinance would be written with the goals of achieving …

An Experiment On Integrated Thermal Management Using Metallic Foam, Derek M. Geiger

Master's Theses

This report details an approach to using metal foam heat exchangers inside an integrated thermal management system on a variable cycle engine. The propulsion system of interest is a variable cycle engine with an auxiliary, variable flow rate fan. The feasibility of utilizing an open-celled metallic foam heat exchanger in the ducting between the constant and variable-fans on this variable cycle engine to cool the avionics was explored using an experimental approach. Two heat exchangers, 6.3 inch width by 6.3 inch length by 0.5 inch thickness, were constructed from 20 and 40 pores per inch (PPI) metal foam and tested. …

Validation Of Linearized Flight Models Using Automated System-Identification, Keith Eric Rothman

Master's Theses

Optimization based flight control design tools depend on automatic linearization tools, such as Simulink®’s LINMOD, to extract linear models. In order to ensure the usefulness and correctness of the generated linear model, this linearization must be accurate. So a method of independently verifying the linearized model is needed. This thesis covers the automation of a system identification tool, CIFER®, for use as a verification tool integrated with CONDUIT®, an optimization based design tool. Several test cases are built up to demonstrate the accuracy of the verification tool with respect to analytical results and matches with LINMOD. Several common nonlinearities are …

Incremental Validation Of Formal Specifications, Paul S. Corwin

Master's Theses

This thesis presents a tool for the mechanical validation of formal software specifications. The tool is based on a novel approach to incremental validation. In this approach, small-scale aspects of a specification are validated, as part of the stepwise refinement of a formal model.

The incremental validation technique can be considered a form of "lightweight" model checking. This is in contrast to a "heavyweight" approach, wherein an entire large-scale model is validated en masse.

The validation tool is part of a formal modeling and specification language (FMSL), used in software engineering instruction. A lightweight, incremental approach to validation is beneficial …

Evaluation Of Herbicide Efficacy As Influenced By Adjuvant And Nozzle Type, Catherine L. (Grissom) Ansolabehere

Master's Theses

White clover (Trifolium repens) is a common and difficult weed to control in turfgrass as it is a highly visible and unsightly weed that disrupts the uniformity of the turfgrass surface. This weed is a serious problem in the turfgrass industry in California and there is a need for better methods of control. With more regulations on pesticides and less information about efficient application techniques, controlling white clover with available herbicides can be difficult.

Compatibility trials were conducted during the summer of 2005 to determine the compatibility of the herbicides and adjuvants planned for use in subsequent greenhouse and field …

Development Of A Laboratory Protocol For The Micropropagation Of Monterey Pines (Pinus Radiata), Año Nuevo Stand, Karen E. Wells

Master's Theses

Monterey pine (Pinus radiata), a native tree to California and two Mexican islands, is important both ecologically and economically. Outside native stands, Monterey pines are grown for landscaping in California and on plantations around the world. Pitch canker, a disease caused by the fungus Gibberella circinata Nirenberg & O’Donnell (Fusarium circinatum Nirenberg and O'Donnell) is threatening the survival of Monterey pines. The disease currently affects Monterey pines in many parts of the world including the native stands. No effective chemical or biological control is available but some Monterey pines show resistance to the disease. The purpose of this project was …

Harmonic Analysis Of A Static Var Compensated Mixed Load System, James David Ruckdaschel

Master's Theses

As power electronic based controllers and loads become more prevalent in power systems, there is a growing concern about how the harmonics generated by these controllers and loads affect the power quality of the system. One widely used power electronic based load is the Variable Frequency Drive (VFDs) used to vary the speed of an induction motor; whereas a common example of a power electronic based controller used in power systems is the Static VAR Compensator (SVC) for improving a system’s power factor. In this thesis, the harmonic content and overall performance of a system including both a VFD and …

Development Of An In-Vitro Tissue Engineered Blood Vessel Mimic Using Human Large Vessel Cell Sources, Dimitri E. Delagrammaticas

Master's Theses

Tissue engineering is an emerging field that offers novel and unmatched potential medical therapies and treatments. While the vast aim of tissue engineering endeavors is to provide clinically implantable constructs, secondary applications have been developed to utilize tissue-engineered constructs for in-vitro evaluation of devices and therapies. Specifically, in-vitro blood vessel mimics (BVM) have been developed to create a bench-top blood vessel model using human cells that can be used to test and evaluate vascular disease treatments and intravascular devices. Previous BVM work has used fat derived human microvascular endothelial cells (EC) sodded on an ePTFE scaffold. To create a more …

Design And Control Considerations For A Skid-To-Turn Unmanned Aerial Vehicle, Tanner Austin Sims

Master's Theses

The use of Unmanned Aerial Vehicles (UAVs) are rapidly expanding and taking on new roles in the military. In the area of training and targeting vehicles, control systems are expanding the functionality of UAVs beyond their initially designed purpose. Aeromech Engineering’s NXT UAV is a high speed target drone that is intended to simulate a small aircraft threat. However, in the interest of increasing functionality, enabling NXT to accomplish wings level skidding turns provides the basis for a UAV that can simulate a threat from a missile. Research was conducted to investigate the aerodynamic and performance characteristics of a winged …

Comparison And Design Of Simplified General Perturbation Models (Sgp4) And Code For Nasa Johnson Space Center, Orbital Debris Program Office, Nicholas Z. Miura

Master's Theses

This graduate project compares legacy simplified general perturbation model (SGP4) code developed by NASA Johnson Space Center, Orbital Debris Program Office, to a recent public release of SGP4 code by David Vallado. The legacy code is a subroutine in a larger program named PREDICT, which is used to predict the location of orbital debris in GEO. Direct comparison of the codes showed that the new code yields better results for GEO objects, which are more accurate by orders of magnitude (error in meters rather than kilometers). The public release of SGP4 also provides effective results for LEO and MEO objects …

Shear Strength And Artificial Aging Characterization For Silicone Bonding Of Polyisobutylene (Pibs) Blends In Relation To Their Use As Lead Insulation Material, Shawn Grening

Master's Theses

In order to take advantage of the properties of poly(styrene-isobutylene-styrene) PIBS and PIB based blends as lead insulation materials, they must be able to sufficiently bond to the various materials that make up the cardiac device. The bonded PIBS must be able to withstand the mechanical stress and corrosive environment of the human body due to the long term use of these devices. Based on the component requirements of lead insulation, the first objective of this study was to perform an initial screening of multiple PIBS / stainless steel / silicone adhesive combinations. The specific polymers of interest were PIBS, …

A Strategy Oriented, Machine Learning Approach To Automatic Quality Assessment Of Wikipedia Articles, Gabriel De La Calzada

Master's Theses

This work discusses an approach to modeling and measuring information quality of Wikipedia articles. The approach is based on the idea that the quality of Wikipedia articles with distinctly different profiles needs to be measured using different information quality models. To implement this approach, a software framework written in the Java language was developed to collect and analyze information of Wikipedia articles.

We report on our initial study, which involved two categories of Wikipedia articles: ”stabilized” (those, whose content has not undergone major changes for a significant period of time) and ”controversial” (articles that have undergone vandalism, revert wars, or …

Pipelined Apache Http Server, Kevin Le

Master's Theses

Web servers often become overloaded with irregular surges in web traffic. Several techniques have been explored to cope with these overloads such as distributing load throughout different servers. This thesis presents Pipelined Apache HTTP Server, a modified version of the Apache Software Foundation’s HTTP Server that utilizes a pipelined execution of Apache’s request cycle. We discuss Apache’s original architecture, the modifications necessary for implementation of pipelined execution, and analyze its run time. Ultimately, we hoped to increase throughput of Apache but fall short because of unbalanced request phases and pipelining overhead.

Bottom-Up Ontology Creation With A Direct Instance Input Interface, Charles C.H. Wei

Master's Theses

In general an ontology is created by following a top-down, or so called genus-species approach, where the species are differentiated from the genus and from each other by means of differentiae [8]. The superconcept is the genus, every subconcept is a species, and the differentiae correspond to roles. To complete it a user organizes data into a proper structure, accompanied with the instances in that domain in order to complete the construction of an ontology. It is a concept learning procedure in a school, for example. Students first learn the general knowledge and apply it to their exercise and homework …

Bamboo: An Alternative Building Material For Urban Ethiopia, Bewketu Z. Kassa

Master's Theses

This project explores the potential of bamboo as an alternative building material for low cost housing units suitable for urban Ethiopia. The rational for the application of bamboo comes from its abundance throughout the country, and its proven physical properties that equate it to other building material like timber, steel and concrete. The proposed bamboo based design solution concentrates on simplification of construction methods, prefabrication of structural components and vertical densification of housing units, addressing the lack of skilled labor, cost of construction time and urban land respectively. An understanding of the design solution was established by constructing a full-scale …

Development Of An Imager System Optimized For Low-Power, Limited-Bandwidth Space Applications, Kalia R. Glassey

Master's Theses

A relatively new picosatellite standard, CubeSats have traditionally been used for simple educational missions. As CubeSats become more complex and utilize more complex sensors such as imagers, they gain enhanced credibility as satellite platforms.

Imaging systems on CubeSats have the potential to be used for a variety of uses, such as earth and weather monitoring, attitude determination, and remote sensing. However the size and power limitations of CubeSats pose an interesting challenge to the design of a capable, robust imaging system.

This thesis outlines the objectives and requirements of CP-3’s imaging system, and describes the development process and methods. Test …

The Effect Of The Fastener Of Different Configuration Composite Panels On Failure Analysis, Robert Austin

Master's Theses

This study presents the effect of the stacking sequence and fiber orientation on a composite sandwich panel subjected to static in-plane bolt loading. Six plates were constructed with laminates of unidirectional carbon fiber and cross ply weaves of fiberglass. The orientations that were examined included 0, +/- 45, and 90 degrees. Half of the plates had fiberglass lamina on the outside of the laminate while the other three plates had the carbon fiber on the outside. Experimental and analytical tests were performed to determine the best orientations and stacking sequence.

For the numerical analysis, plates with fibers oriented at +/- …

Simultaneous Nitrification And Denitrification Of Wastewater Using A Silicone Membrane Aerated Bioreactor, Kirk Hjelte Waltz

Master's Theses

The purpose of this thesis is to investigate the use of a single reactor to biologically treat wastewater by simultaneously oxidizing ammonia, and reducing nitrate and nitrite. The Environmental Protection Agency (EPA) places strict discharge restrictions on these compounds due to their inherent toxicity to humans, wildlife, and ecosystems. The use of a simultaneous system can assist the conventional wastewater treatment technology that requires separate systems, by creating a system that needs less time and smaller size to reach effluent requirements. To conduct this research, a bench-scale membrane aerated biofilm reactor was built using silicone tubing for aeration. Batch and …

Shielding Effectiveness Of Superalloy, Aluminum, And Mumetal Shielding Tapes, Cindy Suit Cheung

Master's Theses

Using MIL-HDBK-419A, MATLAB and Nomographs, Shielding Effectiveness for the Magnetic Field, Electric Field, and Plane Wave were calculated over a frequency range from 10 Hz to 1 GHz. The three shielding tapes used included superalloy, aluminum, and mumetal. Calculations for Shielding Effectiveness involve the computation of Absorption Loss, Reflection Loss, and Re-Reflection Correction Factor. From the outcome of the calculations, it was suitable to conclude that all three metals fulfill the 40 dB Shielding Effectiveness requirements for SGEMP fields for frequencies greater or equal to 1 MHz. Accordingly, all three shielding tapes provide at least 40 dB of shielding to …

Potential Migration Of Ε-Caprolactam To Water And Wine As Affected By Transportation And Storage, Joseph C. Ianneo

Master's Theses

Abstract: Under normal sealing and storage conditions, Nylon-6, poly-caprolactam-based plastic laminates may release impurities to packaged foods and liquids and the application of heat for cooking often increases the rate of migration. Epsilon-caprolactam is one of the main contaminates found to migrate from a Nylon-6 poly-caprolactam plastic film. The objectives of this study were to determine the effects of solvent, transportation and storage time on the migration of ε-caprolactam from a Nylon-6-based lidding material into water or a white wine substitute (12% ethanol). Polypropylene plastic cups were filled, sealed, packaged, stacked and exposed to a simulated 3-day cross-country shipment. Cups …

Stt Event Stream Feature To Assist Software Testing Of Impantable Devices In St. Jude Medical, Yong J. Park

Master's Theses

During development and testing of the pacemaker and defibrillator device functionality, engineers in the cardiac rhythm management industry use a patient simulator to ensure device functionality properly before device is tested with an animal or a human. The patient simulator is also used in the formal device product testing. In St. Jude Medical, a patient simulator called Simulation Test Tool (STT) has been developed and used by engineers in the company. While the Heart Simulator (HS) feature based on physiological heart model in the STT has been served as a main cardiac rhythm simulation feature, there has been an increasing …

Building An Operational Data Store For A Direct Marketing Application System, Chad Smith

Master's Theses

An operational data store (ODS) can be generally described as an architectural construct that is both similar and different in design and purpose to a data warehouse. It is similar in that it is subject-oriented and integrated from the various systems and sources that feed it. However, it is unique in that the data is volatile and updated on a relatively regular basis, it holds little to no archival data, and the data is kept at a detailed level with little summarization. The purpose of this thesis is to provide an overview of an ODS and the data that it …

Performance Of A Catch Basin Filter And Leachate From Biocidal Media For Stormwater Treatment, Ryan Scott Maclure

Master's Theses

The feasibility of installing biocidal beads into a catch basin filter insert for simultaneous stormwater disinfection and contaminant removal was tested. The catch basin filter insert (DrainPac®) was tested for its sediment, oil and grease, and coliform bacteria removal efficiency in conjunction with bench-scale testing of biocidal polymer beads. DrainPac® catch basin filters are composed of a metal frame, polypropylene filter fabric, and a high-density polymer support basket, and are installed below storm drains. A 12 x 41 in. DrainPac® filter (United Stormwater, Inc.) insert was set in a flume that simulated a large-scale catchment basin. Pond water was gravity …

Phytoremediation Of Weathered Petroleum In Groundwater By Arroyo Willows In Nutrient Amended On-Site Mesocosms, Sarah E. Bragg-Flavan

Master's Theses

PHYTOREMEDIATION OF WEATHERED PETROLEUM IN GROUNDWATER BY ARROYO WILLOWS IN NUTRIENT AMENDED ON-SITE MESOCOSMS

SARAH BRAGG-FLAVAN

A large-scale mesocosm study was conducted to determine if vegetation with willow trees enhances biodegradation and to evaluate the mechanisms of natural biodegradation of weathered petroleum compounds under field conditions. The mesocosms were designed to model conditions at a former oil field where mid-range petroleum distillates were used as a diluent for pumping crude oil contaminated the soil and groundwater at the site with petroleum compounds. Ten mesocosms were constructed at the field site using un-impacted soil and diluent-impacted groundwater from the site. Five …

Impacts Of Delayed Drawdown On Water Quality And Aquatic Biota In Seasonal Wetlands Of The Grassland Ecological Area, Los Banos, California, Kyle Nathan Poole

Master's Theses

The 178,000-acre Grassland Ecological Area in California’s San Joaquin Valley is managed to provide overwintering habitat to waterfowl on the Pacific Flyway. The major management activity is the fall flooding and spring drawdown of wetlands, timed to optimize the availability of forage vegetation and invertebrates for ducks and shorebirds. Wetland drainage contains salt, boron, and trace elements that are, in part, derived from imported surface water but also concentrate during storage in the wetland impoundments. The spring drawdown drainage contributes to occasional water quality violations in the San Joaquin River (SJR) during dry years. Compliance with water quality objectives may …

Optimization Of Gan Laser Diodes Using 1d And 2d Optical Simulations, Sean Richard Keali'i Jobe

Master's Theses

This paper studies the optical properties of a GaN Laser Diode (LD). Through simulation, the GaN LD is optimized for the best optical confinement factor. It is found that there are optimal thicknesses of each layer in the diode that yield the highest optical confinement factor. There is a strong relationship between the optical confinement factor and lasing threshold—a higher optical confinement factor results in a lower lasing threshold. Increasing optical confinement improves lasing efficiency. Blue LDs are important to the future of lighting sources as they represent the final color in the RGB spectrum that does not have a …

Arteriogenic Revascularization Does Not Induce Vascular Function Impairment, Matthew David Yocum

Master's Theses

Functional hyperemia and arteriolar vasodilation are impaired with chronic ischemia. We sought to examine the impact of chronic ischemia on collateral artery function. For this we used two hindlimb ischemia models to dissect the impact of different repair processes on collateral function. Ligation of the femoral artery increases shear stress in the muscular branch and results in outward remodeling and arteriogenesis. In contrast, resection of the femoral artery proximal to the muscular branch induces blood flow divergence and neutral remodeling along with expectedly greater hypoxia and inflammation. On day 14 after each surgery the diameter of the muscular branch was …

Temperature Influence And Heat Management Requirements Of Microalgae Cultivation In Photobioreactors, Thomas Hagen Mehlitz

Master's Theses

Microalgae are considered one of the most promising feedstocks for biofuel production for the future. The most efficient way to produce vast amounts of algal biomass is the use of closed tubular photobioreactors (PBR). The heat requirement for a given system is a major concern since the best algae growth rates are obtained between 25-30 °C, depending on the specific strain. A procedure to determine temperature influence on algal growth rates was developed for a lab-scale PBR system using the species Chlorella. A maximum growth rate of 1.44 doublings per day at 29 °C (optimal temperature) was determined. In addition, …