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Full-Text Articles in Physical Sciences and Mathematics

Syneresis And Rheology Mechanisms Of A Latex-Heur Associative Thickener System, Travis Bruno Smith Dec 2015

Syneresis And Rheology Mechanisms Of A Latex-Heur Associative Thickener System, Travis Bruno Smith

Master's Theses

Rheology modifiers are used in paints and coatings to ease their application to a surface, prevent sagging once applied, and allow the leveling of brushstrokes, among other benefits. The early rheology modifiers were hydroxyethyl celluloses (HECs), a type of non-associative thickener that is relatively inexpensive and synthesized from cellulose, which is abundant. However, coatings that are modified with HECs tend to suffer from poor leveling and syneresis (phase separation). HECs have since been replaced with associative thickeners (ATs). These thickeners, when properly formulated, produce stable dispersions that have improved rheological properties, yet, unlike HECs, are sensitive to changes to the …


Automated Multi-Modal Search And Rescue Using Boosted Histogram Of Oriented Gradients, Matthew A. Lienemann Dec 2015

Automated Multi-Modal Search And Rescue Using Boosted Histogram Of Oriented Gradients, Matthew A. Lienemann

Master's Theses

Unmanned Aerial Vehicles (UAVs) provides a platform for many automated tasks and with an ever increasing advances in computing, these tasks can be more complex. The use of UAVs is expanded in this thesis with the goal of Search and Rescue (SAR), where a UAV can assist fast responders to search for a lost person and relay possible search areas back to SAR teams. To identify a person from an aerial perspective, low-level Histogram of Oriented Gradients (HOG) feature descriptors are used over a segmented region, provided from thermal data, to increase classification speed. This thesis also introduces a dataset …


Sparse Aperture Speckle Interferometry Telescope Active Optics Control System, Matthew Clause Dec 2015

Sparse Aperture Speckle Interferometry Telescope Active Optics Control System, Matthew Clause

Master's Theses

A conventional large aperture telescope required for binary star research is typically cost prohibitive. A prototype active optics system was created and fitted to a telescope frame using relatively low cost components. The active optics system was capable of tipping, tilting, and elevating the mirrors to align reflected star light. The low cost mirror position actuators have a resolution of 31 nm, repeatable to within 16 nm. This is accurate enough to perform speckle analysis for the visible light spectrum. The mirrors used in testing were not supported with a whiffletree and produced trefoil-like aberrations which made phasing two mirrors …


Production And Harvest Of Microalgae In Wastewater Raceways With Resource Recycling, Alexander Colin Roberts Dec 2015

Production And Harvest Of Microalgae In Wastewater Raceways With Resource Recycling, Alexander Colin Roberts

Master's Theses

Microalgae can be grown on municipal wastewater media to both treat the wastewater and produce feedstock for algae biofuel production. However the reliability of treatment must be demonstrated, as well as high areal algae productivity on recycled wastewater media and efficient sedimentation harvesting. This processes was studied at pilot scale in the present research.

A pilot facility was operated with nine CO2-supplemented raceway ponds, each with a 33-m2 surface area and a 0.3-m depth, continuously from March 6, 2013 through September 24, 2014. The ponds were operated as three sets of triplicates with two sets continuously fed …


Revision-Polyurethane-Graphene Nanocomposites For Corrosion-Resistant Coatings, Alexandra Rose Stevenson Sep 2015

Revision-Polyurethane-Graphene Nanocomposites For Corrosion-Resistant Coatings, Alexandra Rose Stevenson

Master's Theses

Corrosion is a prevalent concern throughout the world, causing significant monetary and safety concerns. Research has been dedicated to developing cost-effective solutions for corrosion that will also meet increasingly stringent environmental regulations. The recently discovered nanomaterial graphene has been proposed as a potential component in anticorrosion technology due to its strong air and water barrier properties. However, graphene is a relatively expensive, difficult to synthesize material. By incorporating it into nanocomposites, its properties can be exploited even at low concentrations. Previous work has been conducted involving the preparation of anticorrosive polystyrene-graphene nanocomposites; these materials were found to be effective long-term …


Composition Effects On Sheen And Spread Rate Of An Interior Flat, One Coat Latex Paint Formulation, Dana James Christensen Ii Aug 2015

Composition Effects On Sheen And Spread Rate Of An Interior Flat, One Coat Latex Paint Formulation, Dana James Christensen Ii

Master's Theses

Interior flat, white latex paint is a common coating applied to walls around the world. Development of a coating with one coat hide capability is a pinnacle achievement for paint formulators as it has the potential to save consumers both time and money. One coat paints already exist on the market, but they are limited in color, coverage, and often have many disclaimers. Work done was part of a project initiated by ChemoursTM Titanium Technologies.

The goal of the project presented in this article was to create an interior flat, white latex paint that yields a spread rate of greater …


Hydrologic Response To Conifer Removal From An Encroached Mountain Meadow, Gregory F. Van Oosbree Jun 2015

Hydrologic Response To Conifer Removal From An Encroached Mountain Meadow, Gregory F. Van Oosbree

Master's Theses

Meadows in the Sierra Nevada Mountains are an important ecological resource that have degraded in quality and distribution due to several environmental and anthropogenic stressors. The encroachment of conifers beyond forest meadow ecotones is largely responsible for the decline of meadow habitat throughout the past century. Currently, there is little research that quantifies the hydrologic response to removal of conifers encroaching meadows in terms of implicating successful meadow restoration. This study has implemented a before after control intervention (BACI) study design to determine the hydrologic response associated with the removal of conifers from a historic meadow encroached by conifers. The …


Temporal Changes To Fire Risk In Disparate Wildland Urban Interface Communities, Nicola C. Leyshon Jun 2015

Temporal Changes To Fire Risk In Disparate Wildland Urban Interface Communities, Nicola C. Leyshon

Master's Theses

Since 1990, thirteen fires over 100,000 acres in size have burned in California seven of which were recorded to be some of the most destructive wildfires of all time (California Department of Forestry & Fire Protection 2013). To aid the development of policy that reduces the destruction caused by wildfires, it is important to evaluate how risk changes through time in communities that are expanding into fire-prone areas. The objective of this study is to discover how the likelihood of structural loss is changing in WUI as newer; more fire resilient structures replace older structures on the edges of the …


Geospatial Data Modeling To Support Energy Pipeline Integrity Management, Austin Wylie Jun 2015

Geospatial Data Modeling To Support Energy Pipeline Integrity Management, Austin Wylie

Master's Theses

Several hundred thousand miles of energy pipelines span the whole of North America -- responsible for carrying the natural gas and liquid petroleum that power the continent's homes and economies. These pipelines, so crucial to everyday goings-on, are closely monitored by various operating companies to ensure they perform safely and smoothly.

Happenings like earthquakes, erosion, and extreme weather, however -- and human factors like vehicle traffic and construction -- all pose threats to pipeline integrity. As such, there is a tremendous need to measure and indicate useful, actionable data for each region of interest, and operators often use computer-based decision …


Gpuhelib And Distributedhelib: Distributed Computing Variants Of Helib, A Homomorphic Encryption Library, Ethan Andrew Frame Jun 2015

Gpuhelib And Distributedhelib: Distributed Computing Variants Of Helib, A Homomorphic Encryption Library, Ethan Andrew Frame

Master's Theses

Homomorphic Encryption, an encryption scheme only developed in the last five years, allows for arbitrary operations to be performed on encrypted data. Using this scheme, a user can encrypt data, and send it to an online service. The online service can then perform an operation on the data and generate an encrypted result. This encrypted result is then sent back to the user, who decrypts it. This decryption produces the same data as if the operation performed by the online service had been performed on the unencrypted data. This is revolutionary because it allows for users to rely on online …


Using The Papathoma Tsunami Vulnerability Assessment Model To Forcast Probable Impacts, And Planning Implications, Of A 500-Year Tsunami In Cayucos, California, Andrew Robert Marshall Jun 2015

Using The Papathoma Tsunami Vulnerability Assessment Model To Forcast Probable Impacts, And Planning Implications, Of A 500-Year Tsunami In Cayucos, California, Andrew Robert Marshall

Master's Theses

This report focuses on using the Papathoma Tsunami Vulnerability Assessment Model (PTVA) to demonstrate the vulnerability of Cayucos to a 500-year tsunami, and using the results to inform specific planning recommendations. By modeling inundation with GIS and analyzing building attributes via the PTVA model, this study has gone beyond any previous vulnerability assessments of Cayucos. Findings include: delineation of the most vulnerable areas, estimates of numbers of lost civic buildings, commercial buildings and houses, as well as estimates of people displaced from tsunami damaged homes. The report goes on to discuss what mitigation measures are in place and what further …


Sudden Cardiac Arrest Prediction Through Heart Rate Variability Analysis, Luke Joseph Plewa Jun 2015

Sudden Cardiac Arrest Prediction Through Heart Rate Variability Analysis, Luke Joseph Plewa

Master's Theses

The increase in popularity for wearable technologies (see: Apple Watch and Microsoft Band) has opened the door for an Internet of Things solution to healthcare. One of the most prevalent healthcare problems today is the poor survival rate of out-of hospital sudden cardiac arrests (9.5% on 360,000 cases in the USA in 2013). It has been proven that heart rate derived features can give an early indicator of sudden cardiac arrest, and that providing an early warning has the potential to save many lives. Many of these new wearable devices are capable of providing this warning through their heart rate …


Moxel Dags: Connecting Material Information To High Resolution Sparse Voxel Dags, Brent Robert Williams Jun 2015

Moxel Dags: Connecting Material Information To High Resolution Sparse Voxel Dags, Brent Robert Williams

Master's Theses

As time goes on, the demand for higher resolution and more visually rich images only increases. Unfortunately, creating these more realistic computer graphics is pushing our computational resources to their limits.

In realistic rendering, one of the common ways 3D objects are represented is as volumetric elements called voxels. Traditionally, voxel data structures are known for their high memory requirements. One of the standard ways these requirements are minimized is by storing the voxels in a sparse voxel octree (SVO). Very recently, a method called High Resolution Sparse Voxel DAGs was presented that can store binary voxel data orders of …


Effect Of Surfactant Architecture On Conformational Transitions Of Conjugated Polyelectrolytes, Greg A. Braggin Jun 2015

Effect Of Surfactant Architecture On Conformational Transitions Of Conjugated Polyelectrolytes, Greg A. Braggin

Master's Theses

Water soluble conjugated polyelectrolytes (CPEs), which fall under the category of conductive polymers, possess numerous advantages over other conductive materials for the fabrication of electronic devices. Namely, the processing of water soluble conjugated polyelectrolytes into thin film electronic devices is much less costly as compared to the processing of inorganic materials. Moreover, the handling of conjugated polyelectrolytes can be performed in a much more environmentally friendly manner than in the processing of other conjugated polymers because conjugated polyelectrolytes are water soluble, whereas other polymers will only dissolve in toxic organic solvents. The processing of electronic devices containing inorganic constituents such …


Detecting Change In Central California Coast Coho Salmon Habitat In Scotts Creek, California, From 1997–2013, Ashley Brubaker Hillard Jun 2015

Detecting Change In Central California Coast Coho Salmon Habitat In Scotts Creek, California, From 1997–2013, Ashley Brubaker Hillard

Master's Theses

Scotts Creek, in Santa Cruz County, Calif., supports the southernmost extant population of Coho Salmon (Oncorhynchus kisutch) in North America. In 1997, the California Department of Fish and Game (now Fish and Wildlife) conducted an extensive habitat typing survey of mainstem Scotts Creek, describing all habitat units from the top of the estuary to the limit of anadromy approximately 12 km upstream. I repeated this survey in 2013 to (1) assess changes in the quantity and quality of instream habitat, (2) compare the current condition to goals and standards established in the federal Central California Coast (CCC) Coho …


Calculating Staircase Slope From A Single Image, Nicholas Joseph Clarke Jun 2015

Calculating Staircase Slope From A Single Image, Nicholas Joseph Clarke

Master's Theses

Realistic modeling of a 3D environment has grown in popularity due to the increasing realm of practical applications. Whether for practical navigation purposes, entertainment value, or architectural standardization, the ability to determine the dimensions of a room is becoming more and more important. One of the trickier, but critical, features within any multistory environment is the staircase. Staircases are difficult to model because of their uneven surface and various depth aspects. Coupling this need is a variety of ways to reach this goal. Unfortunately, many such methods rely upon specialized sensory equipment, multiple calibrated cameras, or other such impractical setups. …


Detecting Learning Styles In Video Games, Benjamin Cooley Mar 2015

Detecting Learning Styles In Video Games, Benjamin Cooley

Master's Theses

Video games are increasingly becoming more intelligent, able to adapt themselves to the individual gamer. Learning styles are a set of models used to categorize people into different types of learners to explain why some people learn better through different methods. Since learning and exploration are such fundamental parts of the video game experience, it is interesting to consider the possibility of applying these learning style models to video games, allowing the video game to adapt to its player, providing a better experience. To consider such adaptation, the game must first be able to detect that learning style from how …