Digital Commons Network^™

N-Slope: A One-Class Classification Ensemble For Nuclear Forensics, Justin Kehl

Master's Theses

One-class classification is a specialized form of classification from the field of machine learning. Traditional classification attempts to assign unknowns to known classes, but cannot handle novel unknowns that do not belong to any of the known classes. One-class classification seeks to identify these outliers, while still correctly assigning unknowns to classes appropriately. One-class classification is applied here to the field of nuclear forensics, which is the study and analysis of nuclear material for the purpose of nuclear incident investigations. Nuclear forensics data poses an interesting challenge because false positive identification can prove costly and data is often small, high-dimensional, …

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]. …

Extended-Use Ecg Monitor, Daniel Aaron Soski

Master's Theses

In this thesis, a prototype ECG monitor was developed that is integrated into an elastic shirt and takes a 3-lead ECG for over 5 days. The high-quality measurements can be used to identify markers indicative of various detrimental heart conditions. Measurements recorded by the device are encrypted and stored onto a micro-SD card. Current Holter monitors are expensive and have functional lives less than 48 hours; however, extended duration monitoring has been proven more useful in diagnosis. The device designed demonstrates that ECG measurements can be taken over longer durations without sacrificing quality, comfort, or device cost.

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 …

Prediction Of The Degradation Of Emerging Contaminants During Oxidative Treatment Via Analysis Of Reaction Rate Constants, Kellie Cochran

Master's Theses

Globally, water supplies are diminishing in quality while demand is continually increasing. The municipal water and wastewater sector has been paying increased attention to unregulated emerging organic contaminants. Advanced oxidation processes (AOPs), which produce hydroxyl radicles (•OH), have been developed and implemented to remove recalcitrant emerging contaminants left by conventional treatment processes. The current understanding of the removal efficacy of AOPs for emerging contaminants is limited. This study analyzes the ability of an AOP involving ozone and multi-walled carbon nanotubes (MWCNTs) in removing three specific emerging contaminants: caffeine, atrazine, and phenytoin, which were selected based on their persistence and ubiquity …

Determining Feasibility Of A Propulsionless Microsatellite Formation Flight Mission, Aaron Levis

Master's Theses

Benefits of developing missions with multiple formation flying spacecraft as an alternative to a traditional monolithic vehicle are becoming apparent. In some cases, these missions can lower cost and increase flexibility among other situational advantages. However, there are various limitations that are imposed by these missions that are centered on the concept of maintaining the necessary formation. One such limitation is that of the propulsion system required for each spacecraft. To mitigate the complexity and mass of the onboard propulsion, the pairing of electromagnetic actuators and differential drag to replace the functionality of a propulsive system is investigated. By using …

Mechanical Characterization Of Selectively Laser Melted 316l Stainless Steel Body Centered Cubic Unit Cells And Lattice Of Varying Node Radii And Strut Angle, Christopher James Hornbeak

Master's Theses

An experimental study of several variants of radius and strut angle of the body centered cubic unit cell was performed to determine the mechanical properties and failure mechanisms of the mesostructure. Quasi static compression tests were performed on an Instron® universal testing machine with a 50kN load cell at 0.2mm/min. The test samples were built using a SLM Solutions 125 selective laser melting machine with 316L stainless steel. Test specimens were based on 5mm cubic unit cells, with a strut diameter 10% of the unit cell size, with skins on top and bottom to provide a cantilever boundary constraint. Specimens …

The Analysis And Study Of Power System Designs For Same Polytechnic College In Tanzania, Kevin Lum Hua

Master's Theses

The Mbesese Initiative for Sustainable Development (MISD) is a group aiming to help eliminate extreme poverty in Africa by creating educational opportunity. One project that the group is currently doing is to build Same Polytechnic College (SPC) in Tanzania. As part of the project, this thesis aims to study and analyze the electrical power system and distribution for the college. Based on the projected load profile of the college and high potential for solar generation in Tanzania, several different power systems utilizing local utility AC electricity and/or photovoltaic (PV) DC electricity are explored and simulated for their feasibility and performance. …

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 …

Preparation Of Supramolecular Amphiphilic Cyclodextrin Bilayer Vesicles For Pharmaceutical Applications, Kate E. Frischkorn

Master's Theses

Recent pharmaceutical developments have investigated using supramolecular nanoparticles in order to increase the bioavailability and solubility of drugs delivered in various methods. Modification of the carbohydrate cyclodextrin increases the ability to encapsulate hydrophobic pharmaceutical molecules by forming a carrier with a hydrophobic core and hydrophilic exterior. Guest molecules are commonly added to these inclusion complexes in order to add stability and further increase targeting abilities of the carriers. One such guest molecule is adamantine combined with a poly(ethylene glycol) chain. Vesicles are formed by hydrating a thin film of amphiphilic cyclodextrin and guest molecules in buffer solution that mimics physiological …

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 …

Adaptation Of Vt-Dbr Lasers For Lidar, Luke Horowitz

Master's Theses

Vernier Tuned Distributed Bragg Reflector (VT-DBR) lasers have had great success in the field of Swept-Source Optical Coherence Tomography (SS-OCT) due to their continuous and nearly 40 nm wavelength tuning range in a single longitudinal mode. Fast sweeps allow for real time imaging with micrometer resolution at a distance of a few centimeters. While this laser has proven quite useful as a medical imaging tool via OCT, it has yet to similarly prove itself for general light detection and ranging (LIDAR) applications due to range limitations that arise from a finite laser coherence length. The goal of this thesis is …

Real-Time Object Removal In Augmented Reality, Tyler Dahl

Master's Theses

Diminished reality, as a sub-topic of augmented reality where digital information is overlaid on an environment, is the perceived removal of an object from an environment. Previous approaches to diminished reality used digital replacement techniques, inpainting, and multi-view homographies. However, few used a virtual representation of the real environment, limiting their domains to planar environments.

This thesis provides a framework to achieve real-time diminished reality on an augmented reality headset. Using state-of-the-art hardware, we combine a virtual representation of the real environment with inpainting to remove existing objects from complex environments.

Our work is found to be competitive with previous …

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 …

The Modified-Multiphase Boost Converter: Combined Inductors And Capacitors Topology, Zachary L. Eldredge

Master's Theses

In this work, a modified boost converter design has been implemented in a multiphase configuration with a condensed topology. The modified aspect of the design has already been proven to drastically reduce input current ripple by about 40% in a single-phase implementation. By placing two modified boost converters in parallel with interleaving main switches (multiphase), the input inductors and modified capacitors of the modified topology can be reduced to just one of each, lowering the number of components, size, and cost. Additionally, multiphase DC/DC converters lower input/output voltage and current ripples while delivering more power compared to single-phase converters. By …

Orbital Optimization Of Interplanetary Trajectories With Environmental Perturbations, Eric S. Woods

Master's Theses

For a detailed analysis of orbital optimization, it is desired to incorporate a spacecraft environment model in order to have maximum confidence that the analysis will produce an accurate trajectory. Such a model requires the addition of orbital perturbations, or small forces acting on the spacecraft throughout its trajectory that can eventually accumulate in large distances over time. The optimization method that this thesis is concerned with is STOpS (Spacecraft Trajectory Optimization Suite), a Matlab optimizer created by Timothy J. Fitzgerald that utilizes an Island Model Paradigm with five different optimization algorithms. STOpS was originally built to model trajectories with …

A Modified Multiphase Boost Converter With Reduced Input Current Ripple: Split Inductance And Capacitance Configuration, Zoe M. Hay

Master's Theses

This thesis presents the simulation, design, and hardware implementation of a modified multiphase boost converter. Converter design must consider noise imposed on input and output nodes which connect to and influence the operation of other devices. Excessive noise introduces EMI which can damage sensitive circuits or impede their operation. High ripple current degrades battery lifetime and reduces operating efficiency in connected systems such as PV arrays. Converters with high ripple current also experience greater peak conduction loss and require larger components. A two-phase implementation of a modified boost converter demonstrates the input current filtering benefits of the modified topology with …

Design And Verification Of A Labview Automated Antenna Radiation Pattern Measurement System, Dylan C. Bloom

Master's Theses

In 2014, Toyon Research Corporation donated a 6’x6’x8’ anechoic chamber to the Cal Poly EE department to advance student education in the areas of antennas and wireless communications. An anechoic chamber is a room designed to suppress electromagnetic radiation reflections so that accurate measurement of radio frequency (RF) systems such as wireless radios and antennas can take place. Despite the fact that Cal Poly already has a larger anechoic chamber, primarily used for antenna characterization, it is the purpose of this project to design, code, and equip the new chamber so that it performs at least as good, or better …

Bird Abundance At Bird Feeders In Response To Temperature, Wind Speed And Precipitation During The Winter Season, Siddhant Kahal

Master's Theses

The goal of this project is to explore how 23 different bird species respond to 3 climatic attributes. These attributes are lower than average temperatures, wind speed and precipitation level. Information about the bird species and all of the data associated with them is provided by Project FeederWatch (PFW). This is a citizen based survey study that provides key information about bird species abundance through the use of backyard and community feeders. The study volunteers from across the United States and Canada monitor these bird feeders and note important information about the species such as the number of individuals seen. …

Evaluation Of Electrochemical And Laser Polishing Of Selectively Lasermelted 316l Stainless Steel, Julian R. Lohser

Master's Theses

Selective laser melting has shown incredible growth as a metallic additive manufacturing process in recent years. While it does provide many solutions and new ways to approach challenges, it does not come without issues of its own, namely, surface roughness. In the as-printed state, the surface roughness of selectively laser melted parts is unacceptable for use in engineering applications. Additionally, selective laser melting is used to produce complex geometries with hard to reach features, preventing conventional mechanical polishing from being successful. Therefore, it is necessary to evaluate non-mechanical polishing processes as treatments for surface roughness. In this study, electrochemical and …

The Gods Have Taken Thought For Them: Syncretic Animal Symbolism In Medieval European Magic, Solange Nicole Kiehlbauch

Master's Theses

This thesis investigates syncretic animal symbolism within medieval European occult systems. The major question that this work seeks to answer is: what does the ubiquity and importance of magical animals and animal magic reveal about overarching medieval perceptions of the world? In response, I utilize the emerging subfield of Animal History as a theoretical framework to draw attention to an understudied yet highly relevant aspect of occult theory and practice. This work argues that medieval Europeans lived in a fundamentally “enchanted” world compared to our modern age, where the permeable boundaries between physical and spiritual planes imbued nature and its …

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 …

Polycommit: Building Better Habits Through Gamification, Elliot Fiske

Master's Theses

Computer-assisted learning is older than Turing machines, and constantly evolves as technology improves. While some teachers are resistant to using technology in the classroom, “e-learning” techniques are becoming more common in almost every school, from K-12 to universities. As technology becomes more widespread, it becomes crucial to examine the various methodologies of computer-assisted learning and find the techniques that are most effective.

This paper explores the effectiveness of one such methodology, spaced repetition. This technique applies to homework assignments available to students online. We include an exploration of several existing apps that use this technique, and introduce our own novel …

Hydrologic Response To Conifer Removal And Upslope Harvest In An Encroached Montane Meadow, Noël C. Fie

Master's Theses

Meadows are crucial components to larger river watersheds because of their unique hydrologic and ecological functions. Due to climate change, over grazing, and fire suppression, conifer encroachment into meadows has accelerated. In some western regions, nearly half of all meadow habitat has been loss due to conifer encroachment. Restoration of these hydrologic systems requires tree removal. Many studies exist that address the issue of conifer encroachment in montane meadows, however, few studies focus on the role that conifer removal plays on the encroaching meadow. Furthermore, few studies exist that document the hydrologic change from conifer removal and further restoration steps, …

Using Gaze Tracking To Tackle Duplicate Questions On Community Based Question Answering Websites: A Case Study Of Ifixit, Pankti Gandhi

Master's Theses

The number of unanswered questions on Community based Question Answering (CQA) websites has increased significantly due to the rising number of duplicate questions. This is a serious problem, one that could lead to the decline of such beneficial websites.

This thesis presents novel avenues that use gaze tracking technology and behavioral testing to tackle this problem. Based on prior studies on web search behaviors, we assumed that adding contextual information (snippets) to proposed related questions displayed on the `Ask a Question' page of the CQA website iFixit would improve the asker experience and reduce their tendency to post a new …

Utilizing Permanent On-Board Water Storage For Efficient Deep Space Radiation Shielding, Nathan Ryan Gehrke

Master's Theses

As space technologies continue to develop rapidly, there is a common desire to launch astronauts beyond the ISS to return to the Moon and put human footsteps on Mars. One of the largest hurdles that still needs to be addressed is the protection of astronauts from the radiation environment seen in deep space. The most effective way to defend against radiation is increasing the thickness of the shield, however this is limited by strict mass requirements. In order to increase the thickness of the shield, it is beneficial to make mission critical items double as shielding material.

The human rated …

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 …

Exploring The Concept Of A Deep Space Solar-Powered Small Spacecraft, Kian Guillaume Crowley

Master's Theses

New Horizons, Voyager 1 & 2, and Pioneer 10 & 11 are the only spacecraft to ever venture past Pluto and provide information about space at those large distances. These spacecraft were very expensive and primarily designed to study planets during gravitational assist maneuvers. They were not designed to explore space past Pluto and their study of this environment is at best a secondary mission. These spacecraft rely on radioisotope thermoelectric generators (RTGs) to provide power, an expensive yet necessary approach to generating sufficient power. With Cubesats graduating to interplanetary capabilities, such as the Mars-bound MarCO spacecraft, matching the modest …

Improving Introductory Computer Science Education With Draco, Mike Dongyub Ryu

Master's Theses

Today, many introductory computer science courses rely heavily on a specific programming language to convey fundamental programming concepts. For beginning students, the cognitive capacity required to operate with the syntactic forms of this language may overwhelm their ability to formulate a solution to a program.

We recognize that the introductory computer science courses can be more effective if they convey fundamental concepts without requiring the students to focus on the syntax of a programming language. To achieve this, we propose a new teaching method based on the Design Recipe and Code Outlining (DRaCO) processes. Our new pedagogy capitalizes on the …

Pink And Dude Chefs: Effectiveness Of An After-School Nutrition Knowledge And Culinary Skills Program For Middle School Students To Increase Fruit And Vegetable Consumption, Alyssa S. Vaziri

Master's Theses

The rate of overweight and obesity among adolescents aged 12-19 years has more than tripled since 1980, and disproportionately impacts low-income and marginalized populations. Reduction in adolescent obesity rates may result in decreased health risks, decrease healthcare costs, and increased quality of life. Effective intervention methods for adolescent participants have incorporated nutrition knowledge and culinary skill building into afterschool programs. This study examines whether building knowledge, skills, and confidence through a culinary intervention can improve adolescent participants’ choices of healthful foods through increased fruit and vegetable intake.

Pink and Dude Chefs (PDC) is an afterschool nutrition education and culinary skills …