Engineering Commons^™

Experimental Study And Modeling Of The Gm-I Dependence Of Long-Channel Mosfets, Michael Fong Cheng

Master's Theses

This thesis describes an experimental study and modeling of the current-transconductance dependence of the ALD1106, ALD1107, and CD4007 arrays. The study tests the hypothesis that the I-gm dependence of these 7.8 µm to 10 µm MOSFETs conforms to the Advanced Compact Model (ACM). Results from performed measurements, however, do not support this expectation. Despite the relatively large length, both ALD1106 and ALD1107 show sufficiently pronounced ‘short-channel’ effects to render the ACM inadequate. As a byproduct of this effort, we confirmed the modified ACM equation. With an m factor of approximately 0.6, it captures the I-gm dependence with sub-28% maximum error …

Perturbation Based Decomposition Of Semg Signals, Rachel Huettinger

Master's Theses

Surface electromyography records the motor unit action potential signals in the vicinity of the electrode to reveal information on muscle activation. Decomposition of sEMG signals for characterization of constituent motor unit action potentials in terms of amplitude and firing times is useful for clinical research as well as diagnosis of neurological disorders. Successful decomposition of sEMG signals would allow for pertinent motor unit action potential information to be acquired without discomfort to the subject or the need for a well-trained operator (compared with intramuscular EMG). To determine amplitudes and firing times for motor unit action potentials in an sEMG recording, …

Experimental Optical Pulse Picker For Lawrence Livermore National Lab, Alexander Thomas Wargo

Master's Theses

Proprietary.

Development Of A Myoelectric Detection Circuit Platform For Computer Interface Applications, Nickolas Andrew Butler

Master's Theses

Personal computers and portable electronics continue to rapidly advance and integrate into our lives as tools that facilitate efficient communication and interaction with the outside world. Now with a multitude of different devices available, personal computers are accessible to a wider audience than ever before. To continue to expand and reach new users, novel user interface technologies have been developed, such as touch input and gyroscopic motion, in which enhanced control fidelity can be achieved. For users with limited-to-no use of their hands, or for those who seek additional means to intuitively use and command a computer, novel sensory systems …

Sweep And Taper Analysis Of Surfboard Fins Using Computational Fluid Dynamics, Brandon James Baldovin

Master's Theses

The research presented here provides a basis for understanding the hydrodynamics of surfboard fin geometries. While there have been select studies on fins there has been little correlation to the shape of the fin and its corresponding hydrodynamic performance. This research analyzes how changing the planform shape of a surfboard fin effects its performance and flow field. This was done by isolating the taper and sweep distribution of a baseline geometry and varying each parameter individually whilst maintaining a constant span and surface area. The baseline surfboard fin was used as a template in Matlab to generate a set of …

Wastewater Treatment And Nitrogen Removal In Bench-Scale Photobioreactors Operated With Solids Recycling, Erik Hoffnagle

Master's Theses

This thesis examines the effect of solids recycling on nitrification, organic carbon removal, and algal-bacterial productivity in bench-scale photobioreactors (PBRs) simulating winter pond conditions in San Luis Obispo, California and a 6-acre raceway system in Delhi, California. Two sets of duplicate photobioreactors operated with or without solids recycling were fed primary clarifier effluent (1^oEff) for the first experiment, and facultative pond effluent (FAC) for the second experiment.

In both experiments mean productivity was lower in solids recycled PBRs (3.67 and 2.3 g/m²-day), than in controls without solids recycling (4.15 and 3.9 g/m²-day). When fed …

Design Of A Low-Cost Data Acquisition System For Rotordynamic Data Collection, Gregory S. Pellegrino

Master's Theses

A data acquisition system (DAQ) was designed based on the use of a STM32 microcontroller. Its purpose is to provide a transparent and low-cost alternative to commercially available DAQs, providing educators a means to teach students about the process through which data are collected as well as the uses of collected data. The DAQ was designed to collect data from rotating machinery spinning at a speed up to 10,000 RPM and send this data to a computer through a USB 2.0 full-speed connection. Multitasking code was written for the DAQ to allow for data to be simultaneously collected and transferred …

Strawberry Detection Under Various Harvestation Stages, Yavisht Fitter

Master's Theses

This paper analyzes three techniques attempting to detect strawberries at various stages in its growth cycle. Histogram of Oriented Gradients (HOG), Local Binary Patterns (LBP) and Convolutional Neural Networks (CNN) were implemented on a limited custom-built dataset. The methodologies were compared in terms of accuracy and computational efficiency. Computational efficiency is defined in terms of image resolution as testing on a smaller dimensional image is much quicker than larger dimensions. The CNN based implementation obtained the best results with an 88% accuracy at the highest level of efficiency as well (600x800). LBP generated moderate results with a 74% detection accuracy …

A Higher-Order Method Implemented In An Unstructured Panel Code To Model Linearized Supersonic Flows, Jake Daniel Davis

Master's Theses

Since their conception in the 1960s, panel codes have remained a critical tool in the design and development of air vehicles. With continued advancement in computational technologies, today's codes are able to solve flow fields around arbitrary bodies more quickly and with higher fidelity than those that preceded them. Panel codes prove most useful during the conceptual design phase of an air vehicle, allowing engineers to iterate designs, and generate full solutions of the flow field around a vehicle in a matter of seconds to minutes instead of hours to days using traditional CFD methods. There have been relatively few …

Infection Control In Total Knee Replacement Prosthesis Using Nitric Oxide Releasing Biomaterials, Ashley Widing

Master's Theses

Replacing a weight-bearing joint is accompanied by long procedures, even longer recovery times, and intensive monitoring. This burden increases after infection; a complication requiring revision surgeries and therefore extensive additional recovery time. Infection can present itself at any time during the process, making it hard to predict. Currently, a two-part revision surgery is completed by removing all infected tissue and implanting an antibiotic spacer. The spacer fills the joint gap and is removed prior to the revision total knee replacement. A revision total knee replacement follows the same procedure as the initial surgery. Not only is this detrimental to patient …

Assessing Endothelial Dysfunction Estimating The Differences Between 3 Minute And 5 Minute Reactive Hyperemia, Tamiko K. Saldin

Master's Theses

The purpose of this study was to define a lower standard cuff occlusion time to induce reactive hyperemia in assessing endothelial dysfunction. In this study, strong evidence was found by a novel technique that used oscillometric methods, which supported that 3 minute reactive hyperemia was sufficient to elicit a significant difference in arterial compliance from baseline. Twenty healthy Cal Poly students were assessed, (n=12 female, n=8 male) aged 22 years old with a standard deviation of 2.04 years. Arterial compliance was estimated by measuring the peak-to-peak oscillations for baseline, 3 minute reactive hyperemia, and 5 minute reactive hyperemia tests, with …

Effect Of Aerogel On The Thermal Performance Of Corrugated Composite Sandwich Structures, Jacob Dillon Chess

Master's Theses

Current insulation solutions across multiple industries, especially the commercial sector, can be bulky and ineffective when considering their volume. Aerogels are excellent insulators, exhibiting low thermal conductivities and low densities with a porosity of around 95%. Such characteristics make aerogels effective in decreasing conductive heat transfer within a solid. These requirements are crucial for aerospace and spaceflight applications, where sensitive components exist among extreme temperature environments. When implemented into insulation applications, aerogel can perform better than existing technology while using less material, which limits the amount of volume allocated for insulation. The application of these materials into composites can result …

Midpoint And Endpoint Sustainability Assessment Of U.S. And China Manufacturing: A Comparative Mrio+Recipe Analysis, Mustafa Saber

Master's Theses

Manufacturing is among the most important industries for an economy, which creates value-added, fosters innovation, stimulates employment and economic growth. Therefore, manufacturing industries are crucial for a country’s sustainable development not only for economic reasons but also for social (.e.g. employment, tax, etc.) and environmental ones. Thus, manufacturing activities’ contribution to the economy is critically related with environmental and social impacts. Sustainable economic growth is essential and necessary for a country to provide all necessary goods and services to its growing population.

And, this is highly linke with the creation of new jobs and in this context, manufacturing jobs have …

Generating Exploration Mission-3 Trajectories To A 9:2 Nrho Using Machine Learning, Esteban Guzman

Master's Theses

The purpose of this thesis is to design a machine learning algorithm platform that provides expanded knowledge of mission availability through a launch season by improving trajectory resolution and introducing launch mission forecasting. The specific scenario addressed in this paper is one in which data is provided for four deterministic translational maneuvers through a mission to a Near Rectilinear Halo Orbit (NRHO) with a 9:2 synodic frequency. Current launch availability knowledge under NASA’s Orion Orbit Performance Team is established by altering optimization variables associated to given reference launch epochs. This current method can be an abstract task and relies on …

Assessing Risk In Iot Devices, David Levitsky

Master's Theses

The explosive growth of the Internet of Things ecosystem has thrust these devices into the center of our lives. Unfortunately, the desire to create these devices has been stronger than the one to secure them. Recent attacks have shown us ignoring security in Internet of Things devices can cause severe harm in both a digital and physical sense. This thesis outlines a framework for developers and managers to assess the risk of IoT devices using a weighted scoring system across five different categories. Our case studies suggest that devices with higher security considerations have a better security posture and lower …

Micro-Nozzle Simulation And Test For An Electrothermal Plasma Thruster, Tyler J. Croteau

Master's Theses

With an increased demand in Cube Satellite (CubeSat) development for low cost science and exploration missions, a push for the development of micro-propulsion technology has emerged, which seeks to increase CubeSat capabilities for novel mission concepts. One type of micro-propulsion system currently under development, known as Pocket Rocket, is an electrothermal plasma micro-thruster.

Pocket Rocket uses a capacitively coupled plasma, generated by radio-frequency, in order to provide neutral gas heating via ion-neutral collisions within a gas discharge tube. When compared to a cold-gas thruster of similar size, this gas heating mechanism allows Pocket Rocket to increase the exit thermal velocity …

Investigating The Effect Of An Upstream Spheroid On Tandem Hydrofoils, Joel Tynan Guerra

Master's Theses

This thesis documents a series of three dimensional unsteady Reynolds Averaged Navier-Stokes CFD simulations used to investigate the influence of an upstream prolate spheroid body on tandem pitching hydrofoils. The model is validated by performing separate CFD simulations on the body and pitching hydrofoils and comparing results to existing experimental data. The simulations were run for a range of Strouhal numbers (0.2-0.5) and phase differences (0-π). Results were compared to identical simulations without an upstream body to determine how the body affects thrust generation and the unsteady flow field.

The combined time-averaged thrust increases with Strouhal number, and is highest …

Nanosatellite Launch Data-Logger (Sync), Christopher Martin Gerdom

Master's Theses

CubeSat designers are increasingly looking to incorporate delicate structures and optics into their payloads. These delicate payloads, however, may not survive the required absolute-worst-case launch vibration testing needed for flight certification. To help address this problem, and to better match testing conditions to real-world launch environments, this thesis introduces Sync, a compact 1/4U CubeSat payload designed to collect data on the vibrations and thermal environments CubeSats experience inside a deployer on the way to orbit. This data can be used to better understand the launch environment for different vehicles, and help develop new, more realistic testing guidelines that could enable …

A Computational Analysis Of The Gradient Concentration Profile Of Deet And The Mosquito Behavioral Response, Brandon Carver

Master's Theses

DEET is a common active ingredient in most spatial repellents. DEET is also a volatile organic compound. DEET prevents mosquitoes from detecting and coming into contact with an human individual. Gas sensing technologies such as metal oxide semiconductor sensors can detect VOCs. The World Health Organization provides the majority of efficacy testing methods. This research adapts methods from the WHO and use of MOS sensors to further understand how and why DEET affects mosquitos. A custom developed system is used to measure DEET dissipation and observe mosquito behavioral response to the DEET. DEET dissipations and mosquito behavior is measured within …

Amplifying The Prediction Of Team Performance Through Swarm Intelligence And Machine Learning, Erick Michael Harris

Master's Theses

Modern companies are increasingly relying on groups of individuals to reach organizational goals and objectives, however many organizations struggle to cultivate optimal teams that can maximize performance. Fortunately, existing research has established that group personality composition (GPC), across five dimensions of personality, is a promising indicator of team effectiveness. Additionally, recent advances in technology have enabled groups of humans to form real-time, closed-loop systems that are modeled after natural swarms, like flocks of birds and colonies of bees. These Artificial Swarm Intelligences (ASI) have been shown to amplify performance in a wide range of tasks, from forecasting financial markets to …

A Stormwater Management Model For California Polytechnic State University Campus, Hsuan-Wen Chu

Master's Theses

Developments that have been taking place on Cal Poly campus over the years have altered the natural hydrology of the area. Stormwater management practices could help reduce the impacts of these developments. Computer models can help to design effective and economical stormwater management solutions at a watershed scale. As such, the objective of this study was to develop a stormwater management model for Cal Poly campus. The model was developed based on the utility data obtained from the university and other watershed data available from open sources. Field surveys were conducted to address some anomalies in the utility data, and …

Global Renewable And Nonrenewable Energy Use Impact Assessment Of U.S. Manufacturing: An Integrated Cradle-To-Gate Lca And Dea Approach, Bahadir Ezici

Master's Theses

In this thesis, U.S. manufacturing industries` global supply chain-linked energy use and economic output are investigated considering a total of 16 renewable and nonrenewable energy carriers. A multiregion input output (MRIO) framework is employed to conduct the global supply chain-linked energy use impact assessment. The study period was between 1995 and 2014 based on data availability. Thus, 20 MRIO models were developed. Each MRIO model consists of the 40 largest economies of the world and the rest of the world (ROW) as the 41st country. Each country’s economy was structured into 35 manufacturing and service industries based on the Worth …

Using Offline Activities To Enhance Online Cybersecurity Education, Sarah Padlipsky

Master's Theses

Since the beginning of the 21st century, the United States has experienced the impact of a technological revolution. One effect of this technological revolution is the creation of entirely new careers related to the field of technology, including cybersecurity. Continued growth in the cybersecurity industry means a greater number of jobs will be created, adding to the existing number of jobs that are challenging an under-educated and under-trained workforce. The goal of this thesis is to increase the effectiveness of cybersecurity education. This thesis studies whether an online course in cybersecurity can be enhanced by offline, in-person activities that mirror …

Comparative Analysis Of Electrodynamic Toroidal Radiation Shielding Configurations, Max Rosenberg

Master's Theses

Beyond the protective confines of Earth's atmosphere and magnetosphere, spacecraft are subject to constant bombardment by high-energy charged particles originating from our Sun in the form of Solar Particle Events (SPEs), and from outside the solar system in the form of Galactic Cosmic Rays (GCRs). The harm these particles do can be reduced or mitigated outright through radiation shielding. Because protons and other charged particles comprise most of these radiation particles, strong magnetic fields could be generated around spacecraft to deflect incoming charged radiation particles. This thesis investigates the performance of specific configurations of toroidal superconducting solenoids to generate magnetic …

Fluid Agitation Studies For Drug Product Containers Using Computational Fluid Dynamics, Matthew Hiroki Ichinose

Master's Theses

At Amgen, the Automated Vision Inspection (AVI) systems capture the movement of unwanted particles in Amgen's drug product containers. For quality inspection, the AVI system must detect these undesired particles using a high speed spin-stop agitation process. To better understand the fluid movements to swirl the particles away from the walls, Computational Fluid Dynamics (CFD) is used to analyze the nature of the two phase flow of air and a liquid solution.

Several 2-D and 3-D models were developed using Fluent to create simulations of Amgen's drug product containers for a 1 mL syringe, 2.25 mL syringe, and a 5 …

Logging, Visualization, And Analysis Of Network And Power Data Of Iot Devices, Neal Huynh Nguyen

Master's Theses

There are approximately 23.14 billion IoT(Internet of Things) devices currently in use worldwide. This number is projected to grow to over 75 billion by 2025. Despite their ubiquity little is known about the security and privacy implications of IoT devices. Several large-scale attacks against IoT devices have already been recorded.

To help address this knowledge gap, we have collected a year’s worth of network traffic and power data from 16 common IoT devices. From this data, we show that we can identify different smart speakers, like the Echo Dot, from analyzing one minute of power data on a shared power …

A Computational Fluid Dynamics (Cfd) Analysis Of The Aerodynamic Effects Of The Seams On A Two-Dimensional Representation Of A Soccer Ball, Allen R. Rohr

Master's Theses

Most major sports today use a dedicated ball or projectile with specific shape, size, and surface geometry, except for soccer. Over the history of the sport, the surface geometry and design stayed relatively unchanged, sewn together using 32 pentagonal and hexagonal panels. However, recent innovations in panel designs differ substantially from the traditional 32 panel ball. The effects these new designs have on the aerodynamic characteristics of the ball have remained largely unknown, even with the influx of experimental research completed in the past decade. Experimental studies have been broad in scope, analyzing an entire ball in wind tunnels or …

Hip And Knee Biomechanics For Transtibial Amputees In Gait, Cycling, And Elliptical Training, Greg Orekhov

Master's Theses

Transtibial amputees are at increased risk of contralateral hip and knee joint osteoarthritis, likely due to abnormal biomechanics. Biomechanical challenges exist for transtibial amputees in gait and cycling; particularly, asymmetry in ground/pedal reaction forces and joint kinetics is well documented and state-of-the-art passive and powered prostheses do not fully restore natural biomechanics. Elliptical training has not been studied as a potential exercise for rehabilitation, nor have any studies been published that compare joint kinematics and kinetics and ground/pedal reaction forces for the same group of transtibial amputees in gait, cycling, and elliptical training. The hypothesis was that hip and knee …

Population Curation In Swarms: Predicting Top Performers, Ryan W. Heller

Master's Theses

In recent years, new Artificial Intelligence technologies have mimicked examples of collective intelligence occurring in the natural world including flocks of birds, schools of fish, and swarms of bees. One company in particular, Unanimous AI, built a platform (UNU Swarm) that enables a group of humans to make decisions as a single mind by forming a real-time closed-loop feedback system for individuals. This platform has proven the ability to amplify the predictive ability of groups of humans in realms including sports, medicine, politics, finance, and entertainment. Previous research has demonstrated it is possible to further enhance knowledge accumulation within a …

Ridership Ramp-Up For Fixed-Guideway Transit Projects: An Evaluation Of Initial Ridership Variation, Jill Elizabeth Shinn

Master's Theses

Performance-based planning and programming has increased in popularity for transit project funding in recent years. This methodology focuses on quantitative performance measures to inform decision making. For transit projects, projections or observed ridership is the most commonly used performance measure to evaluate project benefits. Conventional wisdom within the transit industry suggests that measuring the performance of a transit project immediately after project opening may not capture all the project’s benefits, since it takes time for a project to realize its short-term ridership potential, a process commonly referred to as ridership ramp-up. While this idea is both intuitive and appealing, especially …