Digital Commons Network^™

Comparison Of The Effect Of Mineral Trioxide Aggregate And Bioceramics Root Repair Material On Odontoblast Differentiation In Vitro, Saleh Ashkanani

Master's Theses

No abstract provided.

Oral Colonization Of Malassezia Species, Anibal Cardenas

Master's Theses

No abstract provided.

The Effect Of Destoning And Enzymatic Pretreatments On The Biofuel Production From Olive Cake, Patrick Tai

Master's Theses

More than 16,000 tons of olive cake was produced in the United States in 2017. Olive cake is a by-product of olive oil extraction, which has limited animal feed potential, and poses an environmental threat when landfilled due to its high organic load and polyphenol content. This residue has potential for biofuel (bioethanol and biomethane) production because it is rich in polysaccharides such as pectin, hemicellulose, and cellulose. Yet, olive cake contains olive stones that can impede its conversion to biofuel. Therefore, two methods of destoning, centrifugation and screening by horizontal screw press, were first compared. Both methods removed an …

Cultural Orientations As Antecedents Of Career Anchors: An Exploratory Study, Kathrine Agger

Master's Theses

In this study the relationship between cultural dimensions and career anchors was examined. The objective was to uncover whether cultural orientations, measured through cultural dimensions, could be perceived as antecedents of career anchors. Responses from 283 people, distributed over 24 countries and five continents, were collected and a canonical correlation analysis was conducted. Results showed that the relationship between cultural orientations and career anchors could be explained through a smaller set of variables. Specifically, results indicated that the cultural dimensions of uncertainty avoidance and long-term orientation were related to the career anchors of job security/stability and, furthermore, that the cultural …

Hydraulic Sheet Resistance In Paper­-Based Porous Media, Stefan Myles Doser

Master's Theses

This work investigates the special case of in­-plane fluid flow of a Newtonian incompressible fluid across a thin paper-­based porous medium at very low Reynolds numbers (Re ≪ 1). Fluid transport with these characteristics is used in emerging devices such as microscale paper­based analytical devices (μPADs). The mathematical similarity between Darcy’s law and Ohm’s law is considered, and hydraulic equivalents of current, voltage and resistance are determined to propose hydraulic sheet resistance. Darcy flow is predicted under these conditions and tested by experiment at two flow rates of 5 μL/min and 10 μL/min. A device was designed and fabricated to …

An Interpretative Phenomenological Analysis Of 2013 Boston Marathoners' Experience Of Running A Subsequent Boston Marathon, Allison Grace

Master's Theses

While trauma experiences have been explored in several sport-related research studies, there is a lack of research on athletes’ experiences of a terror attack in sport. The present study qualitatively explored the meanings that 2013 Boston Marathoners ascribed to their experience of returning to the Boston Marathon to compete. Eight participants took part in semi-structured interviews. Interviews were analyzed via interpretative phenomenological analysis. Eight themes emerged and were organized temporally around pre-2013 Boston Marathon experience, 2013 Boston Marathon experience, and post-2013 Boston Marathon experience. Results suggest participants initially had difficulty processing their 2013 experience, but ultimately, several participants had a …

Our Homes, Our Stores: Aging In Place For Lgbtq Communities In The San Francisco Bay Area, Simon Dean Jarrar

Master's Theses

The objective of this research was to investigate the impact of gentrification on the social networks and communities of LGBTQ (lesbian, gay, bisexual, transgender, queer) elderly people living in the San Francisco Bay Area. The expectation was that, due to the rising cost of living, people in elderly LGBTQ communities would be relocating; this would result in the fragmentation of support networks and community spaces. I used a two-part interviewing process. In the first interview, I asked participants to tell me about themselves and their lives, as well as what they consider to be important aspects of their lives in …

The Interactive Effects Of Sex Of A Sender And Gender Role On Liking And Perceived Competence In Online Email Communication, Megan Opfer

Master's Theses

The purpose of the present study was to examine how evaluations of an email sender would be influenced by gender role and sex of the sender. It was hypothesized that male senders would be liked more and perceived as more competent than females and that agentic male and communal female senders would be liked more and perceived as more competent than communal male and agentic female senders, respectively. Senders would also be ranked in the following order from most positive scores to least: agentic males, communal females, agentic females, communal males. Using a 2 (sex of participants: male vs female) …

Evaluation Of The Fragility Of East Bay Municipal Utility District (Ebmud) Mokelumne Aqueduct, Sara Chalian

Master's Theses

The East Bay Municipal Utility District provides water to the eastern region of the San Francisco Bay Area. Water is delivered through the Mokelumne Aqueduct, which consists of three large diameter steel pipelines. Approximately 15 miles of the aqueducts cross the fragile Sacramento-San Joaquin Delta. A stability analysis has been conducted to evaluate how resilient the elevated aqueduct is in the Delta. Subsidence in the Delta considerably reduces the lateral support of piles. Based on previous studies, and available survey and LiDAR data, the amount of subsidence in the Delta has been predicted over time. In addition, site-specific seismic studies …

Personality, Technology, And Learning, Andrew Guydish

Master's Theses

Computers continued encroachment on today’s society can be seen in a college lecture hall, where a growing number of students use laptops for their academic needs. Current academic laptop use research predominantly makes broad generalizations across users, indicating that laptop use in the classroom has negative influences on academic outcomes. However, this research neglects to take into account possible individual differences in the users. It is hypothesized that students' levels of conscientiousness and impulsivity would moderate the relationship between laptop use and academic performance, while a student’s multitasking experience would mediate this same relationship, forming a moderated mediation model. Using …

Observational Learning Of A Changing Goal Location In Rats, Ryan Troha

Master's Theses

Observational, or imitative, learning is a vital skill for survival. This type of social learning plays an important role in human development (e.g. Bandura), but is also relevant for other species.

We have developed an observational learning paradigm in which rats must learn the location of food in a T-shaped maze through observation. This is a working memory task with the correct goal changing on a daily basis. Therefore, the observer must attend to the demonstrator rat’s performance on a daily or continuous basis.

F344 rats can be trained to observe the location of food on a T-maze before being …

An Evaluation Of Ultrasonic Shot Peening And Abrasive Flow Machining As Surface Finishing Processes For Selective Laser Melted 316l, Rhys Gilmore

Master's Theses

Additive Manufacturing, and specifically powder bed fusion processes, have advanced rapidly in recent years. Selective Laser Melting in particular has been adopted in a variety of industries from biomedical to aerospace because of its capability to produce complex components with numerous alloys, including stainless steels, nickel superalloys, and titanium alloys. Post-processing is required to treat or solve metallurgical issues such as porosity, residual stresses, and surface roughness. Because of the geometric complexity of SLM produced parts, the reduction of surface roughness with conventional processing has proven especially challenging. In this Thesis, two processes, abrasive flow machining and ultrasonic shot peening, …

Analysis Of Potential Vermicompost Market In California, Jason Alan Thomas

Master's Theses

Vermicompost transforms agricultural waste into a high quality soil amendment, though market acceptance remains in its infancy. This study examines how growers’ willingness to pay for vermicompost is affected by grower’s crop, region, income per acre, knowledge level of vermicompost and compost, previous use of compost, and the willingness to pay for compost. The survey results pulled together 223 responses from California growers. It was discovered growers’ had less knowledge of vermicompost than compost but were willing to pay more for vermicompost. There was statistical difference amongst the responses. It was shown the market value per ton of vermicompost lies …

Design, Simulation, And Hardware Construction Of A 600 W Solid State Dc Circuit Breaker For The Dc House Project, Calin Matthew Bukur

Master's Theses

DC circuit breakers must be able to arrest overcurrent conditions to prevent electrical equipment and wiring from causing building fires or other hazards from occurring. With more DC renewable sourced structures such as Cal Poly’s DC House, an inexpensive and reliable protection system is necessary to ensure safe energy transfer to the loads. One method of protecting a system is preventing excessive amounts of current to be drawn by the load when the surrounding components are rated at a lesser value. DC circuit breakers act as a monitoring system and barely presents an effect on the voltage or power. With …

Logging And Analysis Of Internet Of Things (Iot) Device Network Traffic And Power Consumption, Ryan Joseph Frawley

Master's Theses

An increasing number of devices, from coffee makers to electric kettles, are becoming connected to the Internet. These are all a part of the Internet of Things, or IoT. Each device generates unique network traffic and power consumption patterns. Until now, there has not been a comprehensive set of data that captures these traffic and power patterns. This thesis documents how we collected 10 to 15 weeks of network traffic and power consumption data from 15 different IoT devices and provides an analysis of a subset of 6 devices. Devices including an Amazon Echo Dot, Google Home Mini, and Google …

Effect Of Aquaponic Vs. Hydroponic Nutrient Solution, Led Light Intensity And Photoperiod On Indoor Plant Growth Of Butterhead, Romaine And Kale (L. Sativa, B. Oleracea), Sean M. Foster

Master's Theses

Vertical farming has been proposed as a solution for providing food security for an increasing, urbanized human population. Light-emitting diode (LED) technology has become increasingly affordable and efficient, making it an ideal choice as artificial lighting for indoor farms. Still largely undiscovered parameters are the optimal plant varieties and types of production systems for plant growth, profit, and human nutrition. Aquaponics may be able to provide sustainable animal protein for vertical farms, increasing their ability to provide more substantial nutrition to consumers. This research aimed to better understand vertical farming as a food production system, and to determine if aquaponics …

Detection Method Of Subclinical Atherosclerosis Of The Carotid Artery With A Hemodynamics Modeling Approach, Marisa Peressini

Master's Theses

Subclinical atherosclerosis is an important area of research to evaluate stroke risk and predict localization of plaque. The current methods for detecting atherosclerosis risk are insufficient because it is based on The Framingham Risk Score and carotid intima media thickness, therefore an engineering detection model based on quantifiable data is needed. Laminar and turbulent flow, dictated by Reynolds number and relative roughness, was modeled through the carotid artery bifurcation to compare shear stress and shear rate. Computer-aided design and fluid flow software were used to model hemodynamics through the carotid artery. Data from the model was derived from governing equations …

Characterization And Removal Efficiency Comparison Of Bioretention Soil Media Mixtures, Nathan T. Hanson

Master's Theses

Bioretention cells have become a commonly used green infrastructure technique to help infiltrate and remove contaminants from stormwater runoff. Bioretention cells are constructed from a layered or heterogeneous soil mixture designed to optimize their ability to infiltrate influent stormwater and remove contaminants carried by the water as it filters through the soil media. The soil mixture, composition, and planting vary depending the local regulatory agencies. As urbanization occurs across the United States, more natural land is converted from pervious surfaces, such as grasslands and forests, to impervious surfaces such as asphalt and concrete, to help reduce the impact of the …

Nutrient Removal In Microalgae Raceway Ponds And Nitrification Modeling, Esmeralda Diego

Master's Theses

This thesis explores the treatment of municipal wastewater using pilot-scale raceway ponds and looks specifically at the capability of the raceways in removing BOD and nitrogen. Nine 33 square-meter algal raceway ponds were used to conduct research at the San Luis Obispo Water Resources Recovery Facility. Main objectives of this study were to increase the removal of total ammonia nitrogen (NH₃-N plus NH₄⁺-N) from municipal wastewater through increased assimilation and nitrification. Raceway ponds with CO₂ addition were operated in series with an intermediate settling step and a total hydraulic retention time (HRT) of 4 …

Effect Of Bioaugmentation Product Biowish® Aqua™ On Nitrogen Removal In Wastewater, Patrick Cassidy Kalvass

Master's Theses

Biological nutrient removal (BNR) from wastewater, and specifically nitrogen removal, is a growing concern to wastewater dischargers such as municipalities. Excess nutrients in effluent can create problems such as eutrophication, toxicity to aquatic life, and dissolved oxygen depletion in receiving waters. BNR systems have been installed in many locations with success, but their operation presents operational and financial demands greater than conventional biological treatment. Nitrogen removal is typically performed in sequential autotrophic nitrification and denitrification, which increases needed energy input, operational complexity, and therefore cost. Simultaneous nitrification-denitrification (SNdN) achieved in a single system has also been successfully implemented, however operational …

Strategic Selection Of Training Data For Domain-Specific Speech Recognition, Daniel Girerd

Master's Theses

Speech recognition is now a key topic in computer science with the proliferation of voice-activated assistants, and voice-enabled devices. Many companies over a speech recognition service for developers to use to enable smart devices and services. These speech-to-text systems, however, have significant room for improvement, especially in domain specific speech. IBM's Watson speech-to-text service attempts to support domain specific uses by allowing users to upload their own training data for making custom models that augment Watson's general model. This requires deciding a strategy for picking the training model. This thesis experiments with different training choices for custom language models that …

Jupyterlab_Voyager: A Data Visualization Enhancement In Jupyterlab, Ji Zhang

Master's Theses

With the emergence of big data, scientific data analysis and visualization (DAV) tools are critical components of the data science software ecosystem; the usability of these tools is becoming extremely important to facilitate next-generation scientific discoveries. JupyterLab has been considered as one of the best polyglot, web-based, open-source data science tools. As the next phase of extensible interface for the classic iPython Notebooks, this tool supports interactive data science and scientific computing across multiple programming languages with great performances. Despite these advantages, previous heuristics evaluation studies have shown that JupyterLab has some significant flaws in the data visualization side. The …

Enhanced Detection Of Corrosion And Coating Aging Mechanisms Using Core-Shell Quantum Dots, Raymond Thai

Master's Theses

Understanding aging mechanisms in coatings during their servicable life is complicated, due to the inherent stochastic nature of exposure profiles, service environments, and rare weather events. Thus, the development of improved test methods for service life prediction and accelerated weathering relies on the availability of infallible degradation and exposure data, delivered as a function of cumulative time in service. In a related application, non-destructive evaluative methods rely on the premise of being able to probe or monitor in situ mechanisms within a coating system without interfering with actual aging mechanisms. Ultimately, quantumdots can be utilized as in situ sensors for …

Assessing The Photoprotective Effects Of Fluorescent Sphingomyelin Against Uvb Induced Dna Damage In Human Keratinocytes, Rebecca Marie Kandell

Master's Theses

Non Melanoma Skin Cancer (NMSC) affects 3.3 million Americans each year and results from Ultra Violet Radiation (UVR) damage to DNA in the form of pyrimidine dimers and photoproducts [1]–[5]. Cells directly detect the damage and initiate apoptosis, cell cycle arrest, or DNA repair by modulating p53 and p21 levels [6]–[9]. Current methods of photoprotection include sunscreen, but controversy over safety of some active ingredients necessitates research into more natural alternatives [10]–[12]. In particular, 24 hour incubation with bovine milk sphingomyelin (BSM) has demonstrated photoprotective potential by reducing p21 and p53 levels in keratinocytes (KRTs) after UV radiation [13], [14]. …

Tessellated Voxelization For Global Illumination Using Voxel Cone Tracing, Sam Thomas Freed

Master's Theses

Modeling believable lighting is a crucial component of computer graphics applications, including games and modeling programs. Physically accurate lighting is complex and is not currently feasible to compute in real-time situations. Therefore, much research is focused on investigating efficient ways to approximate light behavior within these real-time constraints.

In this thesis, we implement a general purpose algorithm for real-time applications to approximate indirect lighting. Based on voxel cone tracing, we use a filtered representation of a scene to efficiently sample ambient light at each point in the scene. We present an approach to scene voxelization using hardware tessellation and compare …

Study Of The Effect Of Biowish Aqua On Simultaneous Nitrification And Denitrification In A Membrane Aerated Bioreactor, Joelle Arakaki

Master's Theses

This research entails the investigation of the effects of a bioaugmentation product from BiOWiSH^® called Aqua, referred to as “Aqua” for the remainder of this paper, on the nitrogen removal rate in a membrane aerated bioreactor (MABR). This research was conducted using a MABR design that consisted of a silicone membrane and continuous flow airline with compressed air. The membrane system was designed to supply oxygen, creating an aerated layer at the membrane-biofilm interface and an anoxic layer at the biofilm-water interface. Laboratory experiments were conducted to compare the nitrogen removal rates of natural bacteria alone to natural bacteria …

Effects Of Raceway Pond Water And Nutrient Recycling On Microalgae Production And Harvesting, Christian A. Bowen

Master's Theses

To be environmentally sustainable, algae biofuel production requires extensive recycling of water and nutrients during algae cultivation. Such recycling can be in the form of reuse of external wastewaters, such as from municipal sewers, but, to achieve significant biofuels production, internal recycling at the algae farms is also needed. A potential difficulty with internal recycling is the accumulation of auto-inhibitory compounds in recycled algae pond water. An additional concern is that nutrients in the residuals from algae biofuel manufacturing will be only partly bioavailable. Both these factors can limit the extent of internal recycling. Ultimately, combining external and internal recycling …

Effects Of Using Clay Nanoparticles As A Soil Amendment To Remove Nitrate From Stormwater, Megan P. Abutin

Master's Theses

Development of urban areas continues to increase, disrupting the natural ecosystem and the pathways for water to drain into downstream water bodies. As the amount of impervious area increases, pollutants can accumulate on the surface and enter the water cycle by stormwater. In most cities, the stormwater flows into a storm drain that is discharged into a water body. Low Impact Development technology has been developed to treat stormwater prior to discharge downstream. A bioretention cell is used to treat stormwater pollutants such as nitrate, phosphorus, total suspended solids, and metals. Past research has indicated that the removal efficiency of …

Finite-Difference Modeling Of The Batch Process Smoldering Combustion Of Wastewater, Laura H. Kawashiri

Master's Theses

A MATLAB model was developed for the smoldering combustion of wastewater in the context of a decentralized residential wastewater treatment appliance. Data from a batch process sewage smoldering experiment was simulated using implicit finite-difference approximations, assuming one-dimensional transient conductive heat transfer. The time-dependent temperature profiles within the column represented the main parameters of interest and were used to verify recoverable heat energy estimations. Given that the modeling method used for this thesis represents a unique approach, the assumptions and limitations of this model are thoroughly described in the context of reproducing results for other smoldering setups. A lack of convergence …

Acceleration Of Jaccard's Index Algorithm For Training To Tag Damage On Post-Earthquake Images, Kyle John Mulligan

Master's Theses

There are currently different efforts to use Supervised Neural Networks (NN) to automatically label damages on images of above ground infrastructure (buildings made of concrete) taken after an earthquake. The goal of the supervised NN is to classify raw input data according to the patterns learned from an input training set. This input training data set is usually supplied by experts in the field, and in the case of this project, structural engineers carefully and mostly manually label these images for different types of damage. The level of expertise of the professionals labeling the training set varies widely, and some …