Engineering Commons^™

Buck Converter With Voltage Foldback Protection, Fabian Aaron Enriquez, Pedro Rincon Rosales

Electrical Engineering

In this work, we implemented the idea of current foldback protection onto a buck converter. Current foldback protection essentially helps reduce the power dissipation which may be caused by a short circuit or overload scenario. To achieve the goal of this project, we used a combination of comparators, operational amplifiers and MOSFETs to create a current foldback sub controller. This controller would then serve as a feedback device between the output of the converter and the main controller to detect if a fault condition has occurred. Following the design, we performed simulation of the current foldback controller using PSpice and …

Tractor Hacking, Jin Huang, Kyle B. Kesler

Electrical Engineering

Tractor hacking arose from tractor owners' desire for full control over the tractors they purchase. Tractor manufacturers set strict security on the electrical components of their tractors, making it difficult for tractor owners to diagnose and monitor their tractors on their own. The UltraBlue Tractor Hacking project is a solution to this problem, allowing tractor owners to perform diagnostics and monitor the equipment they purchased without having to go through dealerships. From talking to farmers, we found that they valued a diagnostic tool that allows for clearing and resetting Diagnostic Trouble Codes (DTCs), viewing diagnostic data pertaining to a specific …

Portable Ventilator, Bradley C. Weeks, Jack W. Brewer, Sanders Sanabria

Electrical Engineering

The current COVID-19 pandemic has heavily impacted the healthcare system in the United States and elsewhere. The need for patients to have access to a hospital with a ventilator along with a shortage of ventilators for recovery and at-home care as a result of minimal hospital vacancy for patients has been greatly stressed. The presented problem is both an unmet demand and supply of portable and effective ventilators. Existing ventilators have many shortcomings that should be addressed: size, weight, cost, and complexity of current ventilators confines users to stay in a medical facility whilst being monitored by professionals. This both …

Automated Cornhole Score Keeping System, Dominic J. Mingione, Jason D. Chandler

Electrical Engineering

Due to the confusing scoring system and rules of the popular lawn game cornhole, many novice and avid players have difficulty accurately keeping score on a consistent basis. To alleviate this problem, the Automated Cornhole Score Keeping System implements technology that eliminates the need to keep score manually in a game of cornhole. Two cornhole boards, configured with the score keeping system, are able to accurately keep score for both teams throughout the entirety of the game. Each score keeping system communicates through BLE, giving players access to the score of their game from an external scoreboard. Both boards are …

Medical Signal Recognition System Based On Machine Learning, Deep Learning, And Internet Of Things, Arwa Hameed Mohammed Taqi

Theses and Dissertations

Internet of Things (IoT) technology is becoming increasingly common in the healthcare industry. The significant benefits of IoT are decreased operational costs, improved outcomes of the treatment through virtual infrastructures and accessibility of real-time information for making informed decisions, improved disease management, reduced errors, and enhanced patient experience. This enables hospitals to address the demands of the ever-growing population in this world. On the other hand, medical signal classification systems are systems that recognize normal from abnormal medical signals. These systems depend on two modes, training mode in which the system learns about the dominant features of the signals, and …

Artificial Intelligence In Real-Time Diagnostics And Prognostics Of Composite Materials And Its Uncertainties – A Review, Muthu Ram Prabhu Elenchezhian, Vamsee Vadlamudi, Rassel Raihan, Kenneth Reifsnider, Erick Reifsnider

UTARI Researcher Publications-Archive

In the era of the 4th industrial revolution of big data, Artificial Intelligence (AI) is widely used in each and every field of composite materials which includes design and analysis, material storage, manufacturing, non-destructive testing (NDT), Structural Health Monitoring (SHM) and Prognostics of its Remaining Useful Life (RUL), Material State (MS) and damage modes. While these AI models are rapidly developed and integrated into the Industrial Internet of Things (IIoT) to keep track of the health of a composite material from its birth to death, these integrations remain uncertain for prognostics without the certainty of its previous material state. This …

Economic And Environmental Benefits Of A Reduced Roadside Mowing Program For Kentucky Highways, Chris Van Dyke, Candice Wallace, Doug Kreis

Kentucky Transportation Center Research Report

A growing number of state departments of transportation (DOTs) are introducing conservation mowing programs that aim to reduce the frequency of roadside mowing while expanding the footprint of pollinator habitat. Wanting to get a better handle on the utility conservation mowing, the Kentucky Transportation Cabinet (KYTC) funded this study to explore the economic and environmental benefits that accrue from mowing less often. This report presents a synthesis of best conservation mowing practices based on a review of landscape management policies, programs, and procedures in use at 15 state DOTs. Most agencies divide the roadside into discrete management zones. While they …

A Game-Theoretic Framework To Regulate Freeriding In Inter-Provider Spectrum Sharing, Mostafizur Rahman, Murat Yuksel, Thomas Quint

Electrical and Computer Engineering Faculty Publications

Primary-secondary spectrum sharing is limited in terms of design space, and may not be sufficient to meet the ever-increasing demand of connectivity and high signal quality. The next step to increase spectrum sharing efficiency is to design markets where sharing takes place among primary providers rather than leaving it to the limited case where the primary licensee is idle. Attaining contractual spectrum sharing among primary providers, a.k.a. co-primary or inter-provider sharing, involves additional costs for the users, e.g., roaming fee. Co-primary spectrum sharing without additional charge to the users poses two major challenges: a) regulatory approaches must be introduced to …

Impact Of Electric Vehicle Charging On The Performance Of Distribution Grid, Sina Ibne Ahmed, Hossein Salehfar, Daisy Flora Selvaraj

EERC Publications, Papers, & Presentations

This study has assessed the impacts of Level 1, Level 2, and DC fast charging of electric vehicles (EVs) on distribution feeder by varying the EV penetration level. Both graphical and real-time simulations have been conducted to evaluate the vehicle-charging effect on the distribution system. The outcome of the study demonstrates voltage deviation and distortion on the distribution grid.

Cultivating Creativity In Aerospace Systems Engineering To Manage Complexity, Kenneth Lucas Dodd

Master's Theses

In recent decades, complexity in aerospace programs has been increasing, leading to large budget and schedule overruns. Many of the risks of complex system development can be attributed to the inadequacy of linear methods when applied to nonlinear domains, i.e., oversimplification in a program amplifies the amount of risk produced when a system behaves unexpectedly. Effectively managing complexity involves responding to the various sources of complexity, whether it appears in the objective behavior of the system itself or in the subjective behavior of the people developing it. Thus, the engineering of complex systems requires nonlinear modeling methods of the system …

Natural Molybdenite-And Tyrosinase-Based Amperometric Catechol Biosensor Using Acridine Orange As A Glue, Anchor, And Stabilizer For The Adsorbed Tyrosinase, Yan Zhang, Yue Wang, Zhiqiang Zhang, Ahmed Sobhy, Susumu Sato, Masaya Uchida, Yasushi Hasebe

Mining Engineering Faculty Research & Creative Works

To develop a natural mineral-based electrochemical enzyme biosensor, natural molybdenite (MLN), tyrosinase (TYR), and acridine orange (AO) were coadsorbed onto a glassy carbon electrode (GCE). The developed TYR/AO/MLN-GCE-based amperometric TYR biosensor exhibited excellent performance for highly sensitive determination of catechol (linear range, 0.1-80 μM; sensitivity, 0.0315 μA/μM; LOD, 0.029 μM; response time, <4 >s) with good reproducibility and good operational and storage stabilities. The electrochemical impedance spectroscopy (EIS) and quartz crystal microbalance with dissipation (QCM-D) revealed interesting roles of AO: (1) an efficient glue for enhancing the amount of the adsorbed TYR on the MLN-GCE, (2) an anchor for efficient orientation …

Removal Of Sb Impurities In Copper Electrolyte And Evaluation Of As And Fe Species In An Electrorefining Plant, Ana I. González De Las Torres, Michael S. Moats, Guillermo Ríos, Ana Rodríguez Almansa, Daniel Sánchez-Rodas

Materials Science and Engineering Faculty Research & Creative Works

Antimony and arsenic concentrations and their oxidation states (Sb(III), Sb(V), As(III) and As(V)) in copper electrorefining electrolyte can affect copper cathode quality through the formation of floating slimes. A laboratory-scale pilot plant was operated to remove Sb from commercial electrolyte. The pilot plant consisted of a pre-treatment process with copper shavings followed by ion exchange. The results indicated that Sb(III) was removed from copper electrolyte completely, while Sb(V) was partially eliminated. The concentrations of As(III) and As(V) were not affected, and the poisoning of the ion exchange resin by Fe(III) was avoided by pre-reduction to Fe(II) by copper shavings. The …

Fabricating Tinicu Ternary Shape Memory Alloy By Directed Energy Deposition Via Elemental Metal Powders, Yitao Chen, Xinchang Zhang, Mohammad Masud Parvez, Joseph William Newkirk, Frank W. Liou

Materials Science and Engineering Faculty Research & Creative Works

In this paper, a TiNiCu shape memory alloy single-wall structure was fabricated by the directed energy deposition technique with a mixture of elemental Ti, Ni, and Cu powders following the atomic percentage of Ti50Ni45Cu5 to fully utilize the material flexibility of the additive manufacturing process to develop ternary shape memory alloys. The chemical composition, phase, and material properties at multiple locations along the build direction were studied, using scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, Vickers hardness test-ing, tensile testing, and differential scanning calorimetry. The location-dependent compositions of martensitic TiNi and austenitic TiNi phases, mechanical properties, and functional properties …

Towards Enabling Unmanned Aerial Vehicles As A Service For Heterogeneous Applications, Farid Nait-Abdesselam, Ahmad Alsharoa, Mohamed Y. Selim, Daji Qiao, Ahmed E. Kamal

Electrical and Computer Engineering Faculty Research & Creative Works

The increasing use of unmanned aerial vehicles (UAVs) in various commercial applications, such as precision agriculture and aerial remote sensing, is fast contributing to a significant growth in the UAV market. Also, it is crucial to provide continuous coverage after failures of wireless network components or additional bandwidth in high traffic situations. By introducing the concept of UAVs as a service (UaaS), we propose a novel framework, dubbed D3S, consisting of four phases: Demand, decision, deployment, and service. The main objective of this framework is to provide a realistic and streamlined approach to support the implementation of the UaaS paradigm. …

Reliable Mode Tracking In Gradient-Based Optimization Frameworks With Flutter Constraints, Taylor Mcdonnell, Andrew Ning

Faculty Publications

In order to construct mode-specific flutter constraints for use in gradient-based multidisciplinary design optimization frameworks, mode tracking must be used to associate the current iteration’s modes with the modes corresponding to each constraint function. Existing mode tracking methods, however, do not provide a method by which to ensure the accuracy of mode associations, making them unsuitable for use in situations where obtaining correct mode associations is critical. To remedy this issue, a new mode tracking method is presented which incorporates backtracking logic in order to maintain an arbitrarily high degree of confidence in mode correlations during gradient-based optimization and/or during …

Mechanical Properties, Translucency, And Low Temperature Degradation (Ltd) Of Yttria (3–6 Mol%) Stabilized Zirconia, R. Sharon Uwanyuze, Sulekha Ramesh, Mark K. King, Nathaniel Lawson, Manoj K. Mahapatra

Materials Science and Engineering Faculty Research & Creative Works

The mechanical properties (hardness and biaxial flexural strength), optical properties (translucency and gloss), and low temperature degradation (LTD) of 3–6 mol% yttria stabilized zirconia have been investigated. The specimens were prepared by conventional solid-state sintering at 1400 °C. The mechanical and optical properties were evaluated for sintered and polished specimens. X-ray diffractometer (XRD) and scanning electron microscope (SEM) were used, respectively, for structural and microstructural investigation. LTD was determined by XRD analysis of the samples aged in a hydrothermal autoclave at 134 °C for 5–108 h. The mechanical and optical properties are found to be microstructure sensitive. The LTD, due …

A Wirelessly Controlled Scalable 3d-Printed Microsystem For Drug Delivery, Farzad Forouzandeh, Nuzhet N. Ahamed, Xiaoxia Zhu, Parveen Bazard, Krittika Goyal, Joseph P. Walton, Robert D. Frisina, David A. Borkholder

Chemical and Biochemical Engineering Faculty Research & Creative Works

Here we present a 3D-printed, wirelessly controlled microsystem for drug delivery, comprising a refillable micro reservoir and a phase-change peristaltic micropump. The micropump structure was inkjet-printed on the back of a printed circuit board around a catheter microtubing. The enclosure of the microsystem was fabricated using stereolithography 3D printing, with an embedded micro reservoir structure and integrated micropump. In one configuration, the microsystem was optimized for murine inner ear drug delivery with an overall size of 19 x 13 x 3 mm3. Benchtop results confirmed the performance of the device for reliable drug delivery. The suitability of the device for …

Roles Of Key Ion Channels And Transport Proteins In Age-Related Hearing Loss, Parveen Bazard, Robert D. Frisina, Alejandro A. Acosta, Sneha Dasgupta, Mark A. Bauer, Xiaoxia Zhu, Bo Ding

Chemical and Biochemical Engineering Faculty Research & Creative Works

The auditory system is a fascinating sensory organ that overall, converts sound signals to electrical signals of the nervous system. Initially, sound energy is converted to mechanical energy via amplification processes in the middle ear, followed by transduction of mechanical movements of the oval window into electrochemical signals in the cochlear hair cells, and finally, neural signals travel to the central auditory system, via the auditory division of the 8th cranial nerve. The majority of people above 60 years have some form of age-related hearing loss, also known as presbycusis. However, the biological mechanisms of presbycusis are complex and not …

Single Step 2-Port Device De-Embedding Algorithm For Fixture-Dut-Fixture Network Assembly, Simone Scafati, Enza Pellegrino, Francesco De Paulis, Carlo Olivieri, James L. Drewniak, Antonio Orlandi

Electrical and Computer Engineering Faculty Research & Creative Works

The de-embedding of measurement fixtures is relevant for an accurate experimental characterization of radio frequency and digital electronic devices. The standard technique consists in removing the effects of the measurement fixtures by the calculation of the transfer scattering parameters (T-parameters) from the available measured (or simulated) global scattering parameters (S-parameters). The standard de-embedding is achieved by a multiple steps process, involving the S-to-T and subsequent T-to-S parameter conversion. In a typical measurement setup, two fixtures are usually placed before and after the device under test (DUT) allowing the connection of the device to the calibrated vector network analyzer coaxial ports. …

Virus And Bacteria Inactivation Using Ultraviolet Light-Emitting Diodes, Vincent Martino, Kyra Oschsner, Paige Elyse Peters, Daniel Zitomer, Brooke K. Mayer

Civil and Environmental Engineering Faculty Research and Publications

The control of infectious diseases is a critical challenge in developing and developed nations alike. Humans can be exposed to pathogenic microorganisms such as viruses and bacteria through numerous routes of transmission, including waterborne transmission. Accordingly, effective water disinfection processes are paramount for public health protection. In this study, the inactivation efficacy of P22 virus and Escherichia coli bacteria was tested using ultraviolet light-emitting diodes (UV LEDs), which provided effective disinfection of both waterborne microorganisms. Using a peak wavelength emission of 255, 265, or 285 nm, the batch-test, UV LED collimated beam system demonstrated high inactivation potential for both microorganisms …

Ai Alzheimer's Early Detection Via Mri Processing, Luke Frey, Siddharth Sharma, Arti Jain

Electrical Engineering

Alzheimer’s Disease (AD) is an irreversible, progressive brain disorder that impairs memory, thinking, and language. Known as the most common form of dementia, AD is the 6th leading cause of death in the United States. It is estimated that currently, nearly 6 million Americans suffer from AD and moreover, the prevalence of AD is projected to grow to 13.8 million being diagnosed by 2050. Considering these projections, hospitals are expected to be diagnosing nearly half a million patients a year. This high volume will lead to technological growth within the diagnosis process along with more effective treatments.

As of now, …

Survey And Design Of Microwave Low-Noise Amplifiers, Omri Yaari, Pavin Virdee

Electrical Engineering

This project is a contest entry in the Wide In-band Receiver area of the 2020 International Microwave Symposium, 5G Low Noise Amplifier Competition [1]. The project includes RF transistor selection, single, two-stage, and cascode models, and RF parameter optimization to maximize the IMS Competition figure of merit along with a supplemental figure of merit [2]. 5G technologies (used in cellphones, IoT, etc.), first introduced in 2018, are on the rise in current society. Fifth generation hardware requires extended capabilities in comparison to 4G (5-20MHz bandwidth EU: 0.6-2.6GHz), including the newly allocated sub 6GHz frequency bands (EU: 3.4-3.8GHz) and wider bandwidth …

Solar Pv Emulator, Tristan Studer, Cody Kremer

Electrical Engineering

The implementation of a solar PV emulator. Creating a controllable testing environment which sufficiently recreates realistic conditions a photovoltaic cell would experience in real world use. The project aims to accurately show the efficiency and reliability of a solar PV cell, opposed to an ideal model which creates unrealistic expectations. The PV emulator implements conditions such as: irradiance, soiling and temperate changes. It gives feedback on a displayed IV curve and/or PV curve so the user may graphically analyze the output their PV cell produces given various conditions. It allows the user selectable conditions the solar cell may experience this …

Solar Photovoltaic Iv Curve Tracer, Jonathan W. Skelly

Electrical Engineering

The Solar Photovoltaic Current-Voltage (IV) Curve Tracer, sponsored by Cal Poly Professor Dale Dolan, characterizes solar array current vs. voltage curves for any given temperature and irradiance. The curve tracer is battery powered, and functions autonomously across loading conditions from short circuit to open load on any sub-450-watt solar array. The curve tracer supports separate data logging modes for both single cells and single modules to maximize data accuracy for each. For testing full strings of solar panels, up to 10 IV curves may be stored in persistent EEPROM memory. Stored data may be recalled later for output to a …

Optimization Of Single Axis Tracker Settings In The Cal Poly Goldtree Solar Farm, Charles A. Studdard, Liliana Reyes

Electrical Engineering

Solar farms use direct sunlight when operating; additionally, solar modules produce the most energy aligned perpendicular to the sun. Single axis solar tracking systems allow the rotation tilted photovoltaic panels to rotate during the day, maintaining the panels at the utmost efficiency angle. Achieving maximum power generation and reducing shade on the panels, make it crucial to have constant optimum positioning. Larger farms contain multiple rows and columns leading the panels to cast shadows on one another. Backtracking happens when you eliminate or reduce shadow casted on panels from adjacent modules. Panels positioned equidistantly and on even terrain allows backtracking …

Led-Based Solar Simulator, Jonathan E. Honrada

Electrical Engineering

Solar simulators are great laboratory tools that help users conduct tests with solar cells indoors. Conventional solar simulators typically use xenon arc bulbs as a light source, which can have considerable disadvantages. Recent projects have sought to design and implement LED-based solar simulators, as they are more power-efficient, inexpensive, and durable.

Based on these advantages, the goal of this project is to create an LED-based solar simulator that can replicate the characteristics of solar light, but also be tunable with controls. This broadens the testing capabilities of the device, allowing users to conduct tests with more narrow spectrums of light …

2021 Department Of Energy Collegiate Wind Competition Electrical System, Grayson Capers, Shane Alayvilla, Justin Rodrigues

Electrical Engineering

In this work, the implementation of the electrical system for Cal Poly’s 2021 Department of Energy Collegiate Wind Competition turbine is described. The mission of this project was to complete the turbine testing tasks to the best of the team’s ability. This system includes an off the shelf slotless permanent magnet synchronous generator and rectifier to produce a DC voltage. To maximize the power output at below-rated wind speeds, current sensors, voltage sensors, and a dynamic load with variable resistance were designed and tested. To curtail the power and rotor speed in high wind events, the turbine was equipped with …

Hybrid Ac/Dc House, Vinh Q. Tran, Casey Winans, Erin O'Rourke

Electrical Engineering

The Hybrid AC/DC house is a proof of concept implementing a DC bus in residential power systems. The implementation of the DC bus is motivated by efficiency through a direct path for DC sources and loads. The avoidance of DC-to-AC and AC-to-DC conversions used in typical residential systems especially those with DC sources such as solar panels could experience higher efficiencies through only DC-to-DC conversions between the sources and the loads.

Understanding Diffusion And Electrochemical Reduction Of Li+ Ions In Liquid Lithium Metal Batteries, Witness Martin, Yang Tian, Jie Xiao

Chemistry & Biochemistry Faculty Publications and Presentations

Lithium metal has drawn significant interest as an anode material for next generation lithium (Li) batteries. However, due to its propensity to form dendrites in commonly used electrolytes during repeated cycling, it has not yet been commercialized in secondary batteries. The formation of a Li protrusion is determined by the relative speed of Li+ ions being reduced and how fast they can be replenished in the vincinity of electrode. However, it is very difficult to quantify such kinetic parameters of Li+ ion in different electrolytes, not mentioning the identification of the desired electrolyte recipe to mitigate Li dendrite formation. Herein, …

Data Mining Of Unstructured Textual Information In Transportation Safety Domain: Exploring Methods, Opportunities And Limitations, Keneth Morgan Kwayu

Dissertations

The unprecedented increase in volume and influx of structured and unstructured data has overwhelmed conventional data management system capabilities in organizing, analyzing, and procuring useful information in a timely fashion. Structured data sources have a pre-defined pattern that makes data preprocessing and information retrieval tasks relatively easy for the current technologies that have been designed to handle structured and repeatable data. Unlike structured data, unstructured data usually exists in an unorganized format that offers no or little insight unless indexed and stored in an organized fashion. The inherent format of unstructured data exacerbates difficulties in data preprocessing and information extraction. …