Digital Commons Network^™

Spread Spectrum Buck Converter, Summer Elise Rutherford, Kyle Brandon Halloran, Brian Taylor Arbiv

Electrical Engineering

Electromagnetic interference (EMI) is an issue prevalent to DC-DC converters. When a system doesn’t effectively filter out external noise or signals, these signals can cause disturbances to the system at large. The switching technology of DC-DC converters (PWM in particular), lends the system susceptible to EMI because there is a prevalent peaks at the switching frequency, meaning any external signals will not be effectively attenuated at this frequency. This can cause significant issues at the input bus of the DC-DC converters because this bus is likely the input of a multitude of devices; the EMI susceptibility caused by switching technology …

Industry Automation And Controls Lab, Nadir Ilyas Khan, Michael Campos, Samantha Bituen

Electrical Engineering

This work details our efforts to build a new industrial automation lab for the Cal Poly San Luis Obispo Electrical Engineering department from the ground up. Thanks to a donation of Modicon M580 programmable logic controllers (PLCs) from Schneider Electric, we built a lab hardware layout to support a learning environment for students. The Electrical Engineering department currently doesn’t offer any courses for students to learn about automation in topics more closely following the topics learned in their curriculum. It will be beneficial for the school and the students to have graduates in the major with some knowledge of controls …

Pv Hybrid Inverter And Bess, Jacob Sussex, William Dresser, Owen Mckenzie, Jonathan Wharton, Derek Seaman

Electrical Engineering

The storage of energy from renewable sources such as photovoltaic based systems is a growing market, with 36 MWh of storage installed in Q1 of 2018. A report from EnergySage earlier this year states that in 2017, 74% of residential solar owners were also interested in energy storage systems. Mainstream systems like Tesla’s Powerwall are competing with other lithium-ion based storage systems from a wide number of providers on the market today. Short term and long term data collection on a system like this could be useful in designing future systems which perform better than the current market offerings. This …

Automatic Gain Control Integrated Circuit, Kyman Huang, Garth Leung, Lauren Williams

Electrical Engineering

This paper aims to describe the design process of an automatic gain controller (AGC) integrated circuit. An AGC is intended to provide variable gain in order to produce a consistent, distortionless output with a wide range of input magnitudes. This implementation was created as a standalone, small IC for audio systems. The chip requires only 7 pins, allowing for a small 8-pin package. LTSpice was used for the circuit design process and initial simulation. Cadence Virtuoso was used for the circuit layout and further simulations. Xilinx Vivado was used for digital circuit design and initial simulations. This project set out …

Alzheimer’S Disease Detection Using Convolutional Neural Netowork & Wavelets, Ean Hendrickson, Gabriel Amancio, Chloe Eusbio, Kaioli Bessert

Electrical Engineering

It is estimated that 5.7 million people in the United States have Alzheimer’s dementia, including about 1 in 10 people above the age of 65. Alzheimer’s disease detection can help doctors to diagnose patients earlier and help them with preventative, proactive treatment. In this project, we attempt to use two different methods to analyze MRI brain images for Alzheimer’s disease detection, one with convolutional neural network and deep learning algorithm, and the other one with discrete wavelet transform. Computer simulation results are presented in the report.

How Grants Improve Public Health In Sanger, California, Emily A. Rudger, Tabitha J. Tolsma, Jamie L. Mosler

City and Regional Planning

This report analyzes public health needs in Sanger, California. Gathering research from the community and generating a background using Healthy People 2020, the project outlines potential grants the community could benefit from, now and in the future. The grant chosen focuses on parks, as physical activity is an important factor and need for the community.

Placemaking & Augmented Reality: A Theoretical Exploration, Erick Sebastian Gomez

City and Regional Planning

Augmented reality is a technology that has the potential to greatly impact current approaches placemaking. Place is an abstract term that refers to the ability of a physical space to have a deeper, more subjective level of meaning for an individual or group of people. Traditional placemaking strategies can impact physical space but their adaptability is often limited by cultural changes or local needs. Augmented reality is a reactive technology through which people are able to manipulate their environments to more closely reflect personal values and communicate ideas. This paper explores current trends and potential applications of augmented reality in …

Foreign Language Teaching Methodologies: A Review And Analysis In Mandarin Chinese And Spanish University Classes, Maiya Shoemaker

World Languages and Cultures

This research paper serves as a capstone project for a graduate of a university’s World Languages and Cultures Department. After four years of studying Spanish and Mandarin Chinese, the language skills learned in these classes are used to return to beginning-level language classes and analyze a selection of their employed teaching methodologies. More specifically, the study provides brief summaries of teaching methodologies, observations from four class sessions, and findings suggesting whether Spanish and Chinese may be taught in similar ways. The observations from the constant sources of linguistic input in the classroom are also accompanied by interviews in the form …

Lasers, Noah B. Caro

Physics

No abstract provided.

Cooking Hand Multi-Tool, Amanda D. Meares, Amy H. Wilson, Ethan G. Littlejohn, Duania A. Evans

Biomedical Engineering

The purpose of this project was to devise a solution for Jorge Segura, a US Marine who was wounded in Afghanistan and had to have his non-dominant arm amputated above the elbow. His current prosthetic attachments are not suited to cooking tasks, so he needed a way to cook more effectively with either prosthetic attachments or accessibility devices. The main tasks that he needed help with was holding down food on cutting boards and stabilizing pots, pans, and bowls especially when stirring. After background research, exploring commercially available devices, and talking with our challenger, our solution was to design three …

Additive Manufacturing Powder Removal: Viper 2.0, Andrew D. Epperson, Sean Mccracken, Melissa O'Neil, Alex Ward

Mechanical Engineering

This report presents the final design review of this senior project team. The project is being sponsored by Lawrence Livermore National Laboratory, a federal design agency. Lawrence Livermore National Laboratory is interested in improving their metal additive manufacturing process. The goal of this senior project is to improve the efficiency and safety of a method currently being used to remove metal powders for additively manufactured components. A senior project team in 2017-2018 created the Vibration Induced Powder Evacuator and Reclaimer (VIPER), a device that uses a vibration motor to shake a printed part until it is clean from excess powder. …

Cal Poly Satellite Positioning Systems: "Thrust Or Bust!", Josh W. Neiman, Milena A. Milich, Gerardo Ramirez, Joshua A. Tran

Mechanical Engineering

Satellites need a way to make precise corrections to their orbit and positioning. The purpose of this project is to design a gimbal mechanism for Astranis that orients an ion thruster along a requested vector. The gimbal must produce any vector within a 2.5° cone in a thirty-minute window. Current systems are expensive and not well suited to this application. The design must be operable in a space environment and optimize mass, size, and reliability. Our design toggles between four discrete positions to achieve an average thrust vector. The gimbal accomplishes this using four solenoids that tilt a plate about …

C6 Wheels, Samuel L. Pizot, Luke Martin, Josh Warner, Jonah Levis

Mechanical Engineering

This document details the C6 Wheels project being undertaken for senior design. The objective is to design and manufacture carbon fiber reinforced polymer wheels for the Cal Poly Formula Society of Automotive Engineers (FSAE) team. The wheel shells will be used on FSAE’s competition vehicles. FSAE requested the wheels to improve the handling characteristics of their vehicles by reducing the unsprung and rotational mass. They have attempted carbon fiber wheels previously but have not yet run any on their vehicles. FSAE specifically proposed the design of carbon fiber shells with an aluminum center as opposed to full carbon fiber wheels …

Nano Fab Lab 63, Brian K. Deemer, Josh Clemons, Nick Brodine, Delaney Fitzsimmons

Mechanical Engineering

Lawrence Livermore National Laboratories (LLNL) has several steps in the production process for ceramic nanofiber tubes that they would like to improve - electrospinning, cutting, rolling, sealing and heat treating. We undertook the challenge to deliver LLNL with a semi-automated process that efficiently integrates the steps of cutting, rolling, and sealing to save time and improve control over end dimensions. In this document, we discuss the technical background of the manufacturing steps currently followed to create nanofiber tubes, identify which steps are incorporated in our prototype and explain how they will interface with one another, define the design requirements, present …

Chrysalis Creek 2019 Bank Of America Merrill Lynch Low Income Housing, Ivy Zhao

City and Regional Planning

Chrysalis Creek provides 40 affordable housing units for very low- and low-income families in Templeton, California. A chrysalis refers to the third stage of growth, where a caterpillar metamorphose into a butterfly. The project name represents the transformative stage in life for families grow in strength, independence, and stability. Chrysalis Creek is the place where families will thrive and be well supported with resources for success.

Chrysalis Creek is a collaborative effort between architecture, planning and business administration students from Cal Poly. The Cal Poly team is working with Peoples’ Self-Help Housing as the development partner. Peoples’ Self-Help Housing is …

Enhancing Dublin's Emergency Road Network For Hazard Preparedness In The Event Of Natural Disaster, Ritu Muralidharan

City and Regional Planning

The purpose of this study is to assess and analyze the City of Dublin’s current emergency road network and provide recommendations to improve emergency evacuation in the event of natural disasters in the City of Dublin, California.

Planning for emergency preparedness, especially in the aftermath of the wildfires in Paradise and Montecito, California, is more relevant than ever. Learning from these disasters highlight the importance of preparedness, as well as the consideration of roadway capacity and conditions to evacuate during emergencies. This study analyzes the volume, capacity, density, and travel time to determine the capability of a mass evacuation in …

A Proposal For An Adu Incentive Program For The City Of Mill Valley, Emi D. Sugiyama

City and Regional Planning

The development of Accessory Dwelling Units (ADUs) is an important option for responding to increases in housing demand, increasing the diversity in housing options, broadening the range of space available, addressing varied financial needs, and increasing density.

Atmospheric Water Harvesting: An Experimental Study Of Viability And The Influence Of Surface Geometry, Orientation, And Drainage, Carson T. Hand

Master's Theses

Fresh water collection techniques have gained significant attention due to global dwindling of fresh water resources and recent scares such as the 2011-2017 California drought. This project explores the economic viability of actively harvesting water from fog, and techniques to maximize water collection. Vapor compression and thermoelectric cooling based dehumidifier prototypes are tested in a series of experiments to assess water collection capability in foggy environments, and what parameters can increase that capability. This testing shows an approximate maximum collection rate of 1.25 L/kWh for the vapor compression prototype, and 0.32 L/kWh for the thermoelectric cooling prototype; compared to 315 …

Evaluation Of Tensile Properties For Selective Laser Melted 316l Stainless Steel And The Influence Of Inherent Process Features, Paul Swartz

Master's Theses

Optimal print parameters for additively manufacturing 316L stainless steel using selective laser melting (SLM) at Cal Poly had previously been identified. In order to further support the viability of the current settings, tensile material characteristics were needed. Furthermore, reliable performance of the as-printed material had to be demonstrated. Any influence on the static performance of parts in the as-printed condition inherent to the SLM manufacturing process itself needed to be identified. Tensile testing was conducted to determine the properties of material in the as-printed condition. So as to have confidence in the experimental results, other investigations were also conducted to …

Multiple Input, Single Output Dc-Dc Conversion Stage For Dc House, Jason Baltierrez

Master's Theses

n this thesis project, a proposed architecture for the multiple input, single output conversion stage for the DC House was designed, simulated, and tested. This architecture allows for multiple different input sources to be used to create a single higher power output source. The design uses a DC-DC boost converter with a parallelable output which has been demonstrated to allow increased total output power as a function of the number of input sources available. The parallelable output has been shown to distribute load amongst the input sources relatively closely to optimize the system. This approach is also desirable since it …

Leaf Functional Traits As Predictors Of Drought Tolerance In Urban Trees, Sophia Huang

Master's Theses

The services that urban trees provide to human society and the natural environment are widely recognized, but urban trees are in jeopardy due to climate change and urban stressors. With drought as a major threat in many areas, it is important for the future of urban forestry to select species composition based upon performance under water stress. Certain leaf functional traits can help horticulturalists more accurately predict water usage of urban trees. Comprehension through rigorous experimentation is lacking, partly due to the thousands of mostly exotic species. Previous studies suggest that species whose leaves have a denser arrangement of smaller …

Design And Analysis Of An Instrumenting Profiler For Webassembly, Chandler Gifford

Master's Theses

This thesis presents the design, implementation, and analysis of WasmProf, an instrumenting profiler for WebAssembly programs. WebAssembly is a compiled language designed for use on the web that, at the time of this writing, is still being actively developed. At present, performance analysis for WebAssembly programs mostly consists of browsers’ built-in sampling profilers. These profilers work well in many cases but only give a statistical estimation of the distribution of function calls and are, therefore, not well-suited for more fine-grained analysis. The WasmProf instrumenting profiler fills this analysis gap. WasmProf is capable of tracking the number of calls made and …

The Development Of Diving Capabilities In Weddell Seal (Leptonychotes Weddellii) Pups Throughout Early Ontogeny, Emma Weitzner

Master's Theses

Weddell seals (Leptonychotes weddellii) are among the deepest diving pinnipeds (i.e., seals, sea lions, and walrus) and one of the best studied marine mammals in the world; as such, these seals are considered a model species for the study of diving physiology and behavior. Adult Weddell seal dive physiology is rather comprehensively understood, yet previous research has excluded an examination of pups’ initial independent diving attempts, beginning instead with the diving capabilities of near-weaning individuals at four to five weeks of age. This is beyond the point many pups have attempted their first independent dives; pups begin to …

Multi-Vector Tracking Of Wifi And Zigbee Devices, Calvin Andrew Laverty

Master's Theses

Location privacy preservation has shifted to the forefront of discussions about next generation wireless networks. While pseudonym-changing schemes have been proposed to preserve an individual's privacy, simulation has shown that new association attack models render these schemes useless. The major contribution of this thesis is the implementation of a tracking network with commodity hardware on the California Polytechnic State University campus which leverages the combination of de-anonymization strategies on captured wireless network data to show the effectiveness of a pseudonym-changing scheme for wireless identification across WiFi and Zigbee protocols.

Simulating Epidemics And Interventions On High Resolution Social Networks, Christopher E. Siu

Master's Theses

Mathematical models of disease spreading are a key factor of ensuring that we are prepared to deal with the next epidemic. They allow us to predict how an infection will spread throughout a population, thereby allowing us to make intelligent choices when attempting to contain the disease. Whether due to a lack of empirical data, a lack of computational power, a lack of biological understanding, or some combination thereof, traditional models must make sweeping assumptions about the behavior of a population during an epidemic.

In this thesis, we implement granular epidemic simulations using a rich social network constructed from real-world …

Surveying Underwater Shipwrecks With Probabilistic Roadmaps, Amy Jeannette Lewis

Master's Theses

Almost two thirds of the Earth's surface is covered in ocean, and yet, only about 5% of it is mapped. There are an unknown amount of sunken ships, planes, and other artifacts hidden below the sea. Extensive search via boat and a sonar tow fish following a standard lawnmower pattern is used to identify sites of interest. Then, if a site has been determined to potentially be historically significant, the most common next step is a survey by either a human dive team or remotely operated vehicle. These are time consuming, error prone, and potentially dangerous options, but autonomous underwater …

Colloid Thruster To Teach Advance Electric Propulsion Techniques To Post-Secondary Students, Alexander M. Powaser

Master's Theses

Colloid thrusters, and electrospray thrusters as a whole, have been around since the 1960s. When they were first developed, the high efficiency and fine thrust control was overshadowed by the high power requirement for such a low thrust that the system provides. This caused the technology to be put on hold for aerospace applications. Now, as small satellites are becoming more prevalent, there has been a resurgence in interest in electrospray thruster technology. The recent advancements in tech- nology allow electrospray thrusters to use significantly less power and occupy less volume than their predecessors. As electrospray technology continues to advance, …

An Analysis Of Changes In Stream Temperature Due To Forest Harvest Practices Using Dhsvm-Rbm, Julia B. Ridgeway

Master's Theses

Forest harvesting has been shown to cause various changes in water quantity and water quality parameters, highlighting the need for comprehensive forest practice rules. Studies show a myriad of impacts to ecosystems as a result of watershed level changes, such as forest harvesting. Being able to better understand the impact that forest harvesting can have on stream temperature is especially critical in locations where federally threatened or endangered fish species are located. The overall goal of this research project is to assess responses in stream temperature to various riparian and forest harvest treatments in a maritime, mountainous environment. The results …

Degradation Of Emerging Contaminants By Advanced Oxidation Using Multi-Walled Carbon Nanotubes And Continuous Ozone Injection, Emily N. Miller

Master's Theses

With a growing population and continuous accumulation of pollutants, water resources worldwide are quickly being depleted. Drastic improvements need to be made in both water conservation and treatment. Advanced oxidation processes (AOPs) have been developed to go above and beyond the capabilities of traditional wastewater treatment facilities to eliminate emerging contaminants from our water systems. AOPs increase the generation of hydroxyl radicals (•OH) in oxidation reactions, which are less selective and more reactive than other oxidants, such as ozone, so they are more effective at degrading persistent compounds. This study explored an AOP that utilizes ozonated multi-walled carbon nanotubes (MWCNTs) …

Characterization Of Resistance Change In Stretchable Silver Ink Screen Printed On Tpu-Laminated Fabrics Under Cyclic Tensile Loading, Corey R. Sutton

Master's Theses

A stretchable silver ink was screen printed to TPU sheets, then tensile coupons of the TPU, both bare and laminated to cotton, Denim and spandex fabric, were subjected to 1000 cycles of 20% uniaxial strain. In-situ resistance measurements of printed traces were processed to generate datasets of maximum and minimum resistance per cycle. A mechanistic fit model was used to predict the resistance behavior of the ink across TPU/fabric levels. The results show that traces strained on TPU laminated to spandex (polyester) fibers had an average rate of increase in resistance significantly lower than that of traces strained on bare …