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Articles 9841 - 9870 of 197941

Full-Text Articles in Engineering

Robust Adaptive Fractional-Order Pid Controller Design For High-Power Dc-Dc Dual Active Bridge Converter Enhanced Using Multi-Agent Deep Deterministic Policy Gradient Algorithm For Electric Vehicles, Seyyed Morteza Ghamari, Daryoush Habibi, Asma Aziz Jun 2025

Robust Adaptive Fractional-Order Pid Controller Design For High-Power Dc-Dc Dual Active Bridge Converter Enhanced Using Multi-Agent Deep Deterministic Policy Gradient Algorithm For Electric Vehicles, Seyyed Morteza Ghamari, Daryoush Habibi, Asma Aziz

Research outputs 2022 to 2026

The Dual Active Bridge converter (DABC), known for its bidirectional power transfer capability and high efficiency, plays a crucial role in various applications, particularly in electric vehicles (EVs), where it facilitates energy storage, battery charging, and grid integration. The Dual Active Bridge Converter (DABC), when paired with a high-performance CLLC filter, is well-regarded for its ability to transfer power bidirectionally with high efficiency, making it valuable across a range of energy applications. While these features make the DABC highly efficient, they also complicate controller design due to nonlinear behavior, fast switching, and sensitivity to component variations. We have used a …


Aggregator Zone Selection For Ev Smart Controls Based-On Ml Clustering Of Grid Strength, Distance, And Charging Homogeneity, Rosemary E. Alden, Sam H. Lowe Ii, Dan M. Ionel Jun 2025

Aggregator Zone Selection For Ev Smart Controls Based-On Ml Clustering Of Grid Strength, Distance, And Charging Homogeneity, Rosemary E. Alden, Sam H. Lowe Ii, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

Smart electric vehicle (EV) charging control methods from a central utility hub often require communication infrastructure over a large service area of electric power distribution systems with a large number of nodes. Industry standards such as Open Charge Point Protocol (OCPP) 2.1 have evolved to include topologies for local controllers to the individual chargers, i.e. EV aggregator zones. A machine learning (ML) application of k-means clustering is proposed to establish zones for coordination of EV charging based on grid strength and EV owner decision-making to charge per day. Very large-scale distribution networks including the IEEE 123 and 8500 benchmark feeders …


Cluster-Based Volt/Var Optimization On A Utility Distribution Feeder With Forecasted Ev Penetration, Steven B. Poore, Grant M. Fischer, Rosemary E. Alden, Evan S. Jones, Aron Patrick, Dan M. Ionel Jun 2025

Cluster-Based Volt/Var Optimization On A Utility Distribution Feeder With Forecasted Ev Penetration, Steven B. Poore, Grant M. Fischer, Rosemary E. Alden, Evan S. Jones, Aron Patrick, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

With significant increase in EV adoption expected in the near future and the associated impacts on power systems, the effect of volt/var optimization (VVO) as the next step to conservation voltage reduction (CVR), requires reevaluation. Implementation of a cluster-based VVO control strategy employs a novel approach with machine learning (ML) load forecasting to reduce device adjustments through k-means clustering of contiguous time steps with similar active power load in which a single adjustment would be sufficient. The cluster-based VVO method is tested on a complex real world utility distribution feeder with 2,018 nodes, 8.65MW peak load, 9 capacitor banks (CBs), …


Hybrid Fea And Meta-Modeling For De Optimization Of A Pm Stator-Excited Motor With A Reluctance Rotor, Oluwaseun A. Badewa, Dan M. Ionel Jun 2025

Hybrid Fea And Meta-Modeling For De Optimization Of A Pm Stator-Excited Motor With A Reluctance Rotor, Oluwaseun A. Badewa, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

This paper presents an innovative method for designing high-performance electric motors by integrating machine learning (ML) based meta-modeling with a differential evolution (DE) optimization algorithm. The approach utilizes finite element analysis (FEA) data to train the ML meta-model, allowing for efficient optimization of high-power-density machines, such as the reluctance rotor and permanent magnet (PM) stator combined excitation motor, which is characterized by nonlinearities. The meta-modeling process employs an Artificial Neural Network (ANN) with 3 hidden layers and uses the motor’s geometrical variables as inputs. The accuracy of the meta-model in capturing the nonlinear relationships between design parameters, core losses, and …


Three And Two Phase Rotating Field Inductive Couplers For Wireless Power Transfer With One Phase Per Layer Windings, Donovin D. Lewis, Lucas Gastineau, Omer Onar, Dan M. Ionel Jun 2025

Three And Two Phase Rotating Field Inductive Couplers For Wireless Power Transfer With One Phase Per Layer Windings, Donovin D. Lewis, Lucas Gastineau, Omer Onar, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

Multiphase inductive wireless charging coils have been proposed recently to improve coupler surface power density, reduce component stress and size, and provide near-constant power delivery to charge mobile electric systems. Several aspects for the fundamental characterization of multiphase coils are explored up to six phases including approximate mutual inductance with size and turn variation, induced voltage, and output power estimation. The relative component stress and size of passive components for resonant operation are compared between the multiphase variants. A combination of an experimentally validated 3D electromagnetic finite element analysis (FEA) and power electronic co-simulations are used to validate the estimated …


Cryogenic Thermal System For Coreless Axial Flux Pm Machine With Litz Wire Winding For Electric Aircraft Propulsion, Matin Vatani, Chaianan Sailabada, Philippe Masson, Juan C. Ordonez, Dan M. Ionel Jun 2025

Cryogenic Thermal System For Coreless Axial Flux Pm Machine With Litz Wire Winding For Electric Aircraft Propulsion, Matin Vatani, Chaianan Sailabada, Philippe Masson, Juan C. Ordonez, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

Electric machines for aviation demand ultra-efficient, compact designs with high specific power density, which can be achieved through advancements in both electromagnetic design and thermal management. This paper proposes and investigates an integrated thermal management approach for a coreless stator axial flux permanent magnet (AFPM) machine featuring a double-sided Halbach array PM rotor, two stators, and an aluminum nitride (AlN) cold plate positioned between the stators for direct cooling. The cold plate incorporates internal serpentine channels for liquid hydrogen circulation. The electromagnetic performance and efficiency of the machine at cryogenic temperatures are assessed using temperature-dependent data from the literature, indicating …


Mitigation Of Pm Eddy Current Losses Using Offset Windings In Coreless Afpm Machines, Matin Vatani, Diego A. Lopez Guerrero, John F. Eastham, Dan M. Ionel Jun 2025

Mitigation Of Pm Eddy Current Losses Using Offset Windings In Coreless Afpm Machines, Matin Vatani, Diego A. Lopez Guerrero, John F. Eastham, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

Permanent magnet eddy current losses can become substantial in coreless stator axial flux permanent magnet (AFPM) machines operating at high speeds and under high electric loading, potentially leading to elevated temperatures and an increased risk of demagnetization. This paper investigates the origins of these losses through a detailed harmonic analysis of the winding factor and introduces a mitigation strategy. The proposed method utilizes two-layer offset windings, effectively minimizing undesirable armature flux harmonics through harmonic interaction between the offset layers. Two cases are studied: one in which each stator layer is connected to a separate inverter and another in which both …


Emergency Bleeding Education Fixture, Nate Colley, Kennedy K. Austin Jun 2025

Emergency Bleeding Education Fixture, Nate Colley, Kennedy K. Austin

Biomedical Engineering: Graduate Reports and Projects

Despite the deadly nature and widespread occurrence of emergency bleeding events, there are currently no training devices or demonstrations which educate users on the urgency of these events and potential methods to address them. Additionally, current models often fail to replicate physiological conditions correctly. A fixture was created to demonstrate the urgency of hemorrhaging events and educate users on potential methods for treating hemorrhaging, namely tourniquets and pressure wraps. This fixture utilized gravity to replicate systolic blood pressure, a silicone model to replicate various adult leg sizes and correct tissue properties, and a tubing system with varying compliance to replicate …


Underground Lrt Station, Revital Mesika Jun 2025

Underground Lrt Station, Revital Mesika

Fire Protection Engineering: Culminating Experience Project Reports

This report presents a comprehensive fire safety and evacuation systems analysis for the underground light rail terminal station project. The station features two main levels— concourse and platform—and is strategically located adjacent to a sports stadium.

Station Overview: The underground light rail terminal station is a two-level facility strategically positioned adjacent to a major sports stadium. The station operates as a critical transportation hub with distinct functional zones designed for efficient passenger flow and emergency evacuation:

Concourse Level (3.5 meters below ground): Functions as the primary passenger processing and circulation hub. This level serves as the main entry control point …


Genesis Station Fire Protection And Life Safety Analysis, Mark Anthony Bautista Jun 2025

Genesis Station Fire Protection And Life Safety Analysis, Mark Anthony Bautista

Fire Protection Engineering: Culminating Experience Project Reports

This fire protection and life safety analysis evaluates GENESIS Station, a nine-story Type I-B mixed-tenant building located in Daly City, California. The facility includes business, research laboratory, and assembly occupancies. A combination of prescriptive code compliance and performance-based analysis was applied to assess the building’s overall fire safety strategy.

The building utilizes a layered fire protection strategy that combines passive fire resistive construction with active systems. Fire rated construction separate tenant suites, limiting the spread of fire and smoke, defining hazardous materials control areas, and ensuring compliant separation of egress paths.

Active fire protection systems include a fully automatic sprinkler …


Srs Training Facility, Brandon Romero Jun 2025

Srs Training Facility, Brandon Romero

Fire Protection Engineering: Culminating Experience Project Reports

This report presents a comprehensive fire protection and life safety analysis of the Savannah River Site (SRS) Training Center. A detailed prescriptive code analysis confirmed the building's compliance with applicable standards regarding construction features, occupancy classification, and fire-rated assemblies. Fire resistance provisions are met, with key areas such as exits, stairwells, and the records storage room. The building’s layout, height, number of stories, and floor area also comply with the allowable limits established by the IBC. Fire protection systems include a proprietary fire alarm system with voice notification, extensive smoke and heat detection coverage, and a wet-pipe sprinkler system designed …


Cryogenic Fuel Delivery System, Carter Josef, Reilly Humphreys, Joseph O'Connor, Nick Spreen Jun 2025

Cryogenic Fuel Delivery System, Carter Josef, Reilly Humphreys, Joseph O'Connor, Nick Spreen

Mechanical Engineering

This project presents the design and validation of a cryogenic fuel delivery system aimed at enabling sustainable aviation through hydrogen fuel vaporization. Developed by a team of senior mechanical engineering students at Cal Poly and sponsored by Boeing, the system utilizes atmospheric air to vaporize liquid nitrogen, used as a stand-in for hydrogen, via forced convection heat exchangers, eliminating the need for engine-supplied heat and reducing parasitic loads. A feedback loop and turbine component are integrated to regulate pressure and recover energy, respectively. A benchtop prototype was built and tested to evaluate system performance, with results closely aligning with analytical …


Conversational Social Robot, Julianna M. Christopoulos, Mackenzie Goldman, Cece E. Hujanen, Jared Hunter Jun 2025

Conversational Social Robot, Julianna M. Christopoulos, Mackenzie Goldman, Cece E. Hujanen, Jared Hunter

Mechanical Engineering

Background: Social robots are used in various settings to reduce burden on human workers and expand opportunities for people in need of assistance.

Challenge: Design a humanoid robot head and torso capable of holding conversations and interacting with a user using a LLM and motion. Conversations are limited to discussing Cal Poly resources and opportunities with visitors to the Bently Research Center on campus.


Scitechatorium, Olivia Lafferty, Yvonne Brien Miller, Colton Swinth, Savannah Pinheiro, Gage Heinze Jun 2025

Scitechatorium, Olivia Lafferty, Yvonne Brien Miller, Colton Swinth, Savannah Pinheiro, Gage Heinze

Mechanical Engineering

Bellevue Santa-Fe Charter School (Bellevue) is a K6th grade public charter elementary school in Avila Beach, California. The primary focus at Bellevue is fostering unique learning experiences, empowering students through project-based learning, and engaging students in creative endeavors. Following these themes, the school has allocated space and funding for an on-campus science and technology museum known as the SciTechatorium. The museum is currently open during students’ lunch period, providing interactive displays on concepts in human biology, nature and wildlife, physics, and electronics. Bellevue’s K-6th grade science teacher, Christian Strauli, and Bellevue parent volunteers are primarily responsible for the museum’s upkeep …


Evoque Delivery System Fixture Optimization, Jack Ellis, Florence Duff, Noah Dunsmore, Timothy Hunter, Rafael Castillo Jun 2025

Evoque Delivery System Fixture Optimization, Jack Ellis, Florence Duff, Noah Dunsmore, Timothy Hunter, Rafael Castillo

Mechanical Engineering

No abstract provided.


3d Printed Fixed Wing Aircraft Competition, Sidney E. Long, Mitchell Heise, Jack Bride, Daniel Salinas Jun 2025

3d Printed Fixed Wing Aircraft Competition, Sidney E. Long, Mitchell Heise, Jack Bride, Daniel Salinas

Mechanical Engineering

Cal State LA and Arlington University, Texas are hosting the same 3D printed, fixed wing aircraft competition for 2025. Cal Poly requires a competitive plane that can adhere to each rule and be piloted remotely to achieve the longest time in the air. The plane must utilize solely 3D printing technology for the wings, body, and all other structures. The only off-the-shelf components can be the motor and electronics, as well as mechanical devices such as hinges.


Combustion Liner Optimization, William Weeks, Daniel Reed, Isaac Trull Jun 2025

Combustion Liner Optimization, William Weeks, Daniel Reed, Isaac Trull

Mechanical Engineering

Solar Turbines provides gas power generation solutions, focusing on gas turbine engines and compressors. The Gas Turbine Products Engineering (GTPE) team at Solar Turbines needs a way to efficiently and cost-effectively maintain the combustion liner of the Taurus model gas turbine at or below the cold-side temperature target. The current system involves a manufacturing process with ergonomic concerns and uncertain cooling effectiveness.

To address this, our team proposed a new combustion liner system featuring impingement cooling. We provided Solar Turbines with heat transfer models of both the existing and proposed designs, demonstrating improved cooling performance. Additionally, a prototype of the …


License To Drill, Gabrielle Noemi Orlando, Alexcias Olga Meeks, Dayana Guadalupe Gonzalez, Mark Dahmen Jun 2025

License To Drill, Gabrielle Noemi Orlando, Alexcias Olga Meeks, Dayana Guadalupe Gonzalez, Mark Dahmen

Mechanical Engineering

The goal of this project is to provide the student machine shops with an updated License to Drill (LTD) certification training, formally known as the Red Tag. The current training has two key components: a preliminary Canvas course and an in-person training with a safety tour, safety quiz, and a hands-on project. Currently, the hands-on project is outdated and unengaging. Thus, the primary focus is to replace it with an inspiring and memorable project, which includes written and visual instructional content on how to make it. The Canvas will thus be updated, a new instructional video will be created, and …


Pendulum Wave Generator, Abigail Jocelyn Romero, Paul Staley, Wendy Dong, Kyle Schumacher Jun 2025

Pendulum Wave Generator, Abigail Jocelyn Romero, Paul Staley, Wendy Dong, Kyle Schumacher

Mechanical Engineering

The Cal Poly Mechanical Vibrations Laboratory (Vibes Lab) serves to educate and excite students about mechanical vibrations through hands-on experiments. While the lab contains several relatively complicated technical experiments, it lacks simple demonstrations with immediate visual interest to appeal to audiences with less technical backgrounds. Because of this, faculty desired a fun and interactive demonstration project that could be operated with no prior training. The project chosen for this is a Pendulum Wave Generator which is a set of multiple pendulums with differing lengths that combine to create complex and observable patterns over time. This project was completed by a …


Adaptive Riding Mount Block, Lucas R. Reynolds, Lukas M. Moreau, Patrick J. Michael, Jandre D. Lafradez Jun 2025

Adaptive Riding Mount Block, Lucas R. Reynolds, Lukas M. Moreau, Patrick J. Michael, Jandre D. Lafradez

Mechanical Engineering

Professor Sarah Stewart from the Animal Science Department at Cal Poly seeks to develop a solution to help people with disabilities mount horses. Users need a mounting block that can bring them closer to the horse’s back to ease mounting. The current system, consisting of two plastic two-step blocks, is inadequate—unstable, too small, and inaccessible for wheelchair users.

The required solution must meet several key specifications: it should accommodate at least three people standing side by side, be sturdy enough to support their combined weight, and remain stable on rugged terrain like gravel or sand without tilting or sinking. Additionally, …


Lidss Raft Battery Pack Integration, Jack Maxwell, Vincent Stevens, Matthew Hoodmaker, Colin Flanders Jun 2025

Lidss Raft Battery Pack Integration, Jack Maxwell, Vincent Stevens, Matthew Hoodmaker, Colin Flanders

Mechanical Engineering

Lawrence Livermore National Laboratory is a critical member of the United States Department of Defense. Their Independent Diagnostics Scoring System (LIDSS) uses rafts that operate in the ocean to collect missile test data. Several times a year, the United States will test their Inter-Continental Ballistic Missiles by launching them into the ocean near the Marshall Islands. This is where the LIDSS rafts collect their test data. Our project was centered around re-designing the battery pack used by the rafts. The current battery pack design experiences water ingress problems and is difficult to access. Our re-designed battery pack is waterproof to …


Ray Collection: Forging A New Fashion Genre, Olivia R. Cooper Jun 2025

Ray Collection: Forging A New Fashion Genre, Olivia R. Cooper

Graphic Communication

This senior project addresses a gap in the fashion industry by creating a new genre through a unique collection and comprehensive branding. The "RAY" collection draws inspiration from the designer's artistic roots and is a deeply personal homage to influential female artists like Frida Kahlo, Louise Bourgeois, and Leonora Carrington, whose works have inspired the designer's creative journey. Each piece in the collection draws direct inspiration from these artists, reflecting the creator's vision and self-expression, a key element of the streetwear genre incorporated into the designs.

The project also heavily emphasizes fashion branding, encompassing a logo, brand identity, social and …


Prepare Lora Physical Layer For Testing In Low Earth Orbit On A Cubesat, Sammy Brunton Jun 2025

Prepare Lora Physical Layer For Testing In Low Earth Orbit On A Cubesat, Sammy Brunton

Electrical Engineering

This project is a collaboration with OWL Integrations, a company that specializes in adaptable, low-cost communication systems. OWL has developed a board specifically designed for space applications called the Space Quacker Advanced Development (SQuAD), which is an adaptation of their existing board called the Quaker Advanced Development (QUAD).

This project focuses on testing the existing SQuAD board design to make sure that it is flight-ready for deployment on Cal Poly CubeSat’s satellite, SAL-E. To achieve this, the project must ensure compatibility with Low Earth Orbit (LEO) conditions by testing the integrated high-power long-range (LoRa) receiver and enhanced hardware to meet …


2024 – 2025 Cal Poly Wind Power Ac-Dc Rectification Subsystem For Collegiate Wind Competition 2025, Ryan Rayos, Annabella Piercey, Alex Liu Jun 2025

2024 – 2025 Cal Poly Wind Power Ac-Dc Rectification Subsystem For Collegiate Wind Competition 2025, Ryan Rayos, Annabella Piercey, Alex Liu

Electrical Engineering

This project focuses on the design and development of a bidirectional AC-DC rectification subsystem for a wind energy conversion system (WECS), tailored for the 2025 Collegiate Wind Competition. The subsystem is defined by its core inputs and outputs where it receives AC power from the wind turbine generator and delivers stable DC power to auxiliary electronics and variable loads. Conversely, the system can also accept DC power, such as from wall power, and output AC power to drive the permanent magnet synchronous machine (PMSM) as a motor, overcoming cogging torque and initiating turbine blade rotation. This bidirectional functionality is enabled …


Expeditionary Ocean Power Generator, Ethan Gossard, Julian Steele, Alex Gray, Hunter Herring-Alderete Jun 2025

Expeditionary Ocean Power Generator, Ethan Gossard, Julian Steele, Alex Gray, Hunter Herring-Alderete

Electrical Engineering

Point Absorber Wave Energy Converters are currently being explored as a new form of energy harvesting. The Naval Facilities' Expeditionary Ocean Warfare Center (NAVFAC EXWC) has commissioned an interdisciplinary project for students at California Polytechnic State University, San Luis Obispo, to design a prototype Expeditionary Ocean Power Generator (ExOPG) for charging batteries in the ocean.

The Mechanical Engineering team is responsible for assembling the prototype chassis, which converts the vertical bobbing motion of a buoy into kinetic rotational energy that can be used to rotate a generator shaft. They are additionally tasked with isolating the electrical components from the harsh …


The Potential Scalability Of High-Pressure Sliding Technique For Developing Ultrafine Grained Material With Enhanced Mechanical Properties Of Aa7075, Eman Zayed, Nahed El-Mahallawy, Mostafa Shazly Jun 2025

The Potential Scalability Of High-Pressure Sliding Technique For Developing Ultrafine Grained Material With Enhanced Mechanical Properties Of Aa7075, Eman Zayed, Nahed El-Mahallawy, Mostafa Shazly

Mechanical Engineering

No abstract provided.


Quantifying Harmful Trunk Postures: Inertial Sensor Analysis Of Trunk Angle To Support Low Back Pain Prevention, Elsa E. Bates Jun 2025

Quantifying Harmful Trunk Postures: Inertial Sensor Analysis Of Trunk Angle To Support Low Back Pain Prevention, Elsa E. Bates

Master's Theses

Low back pain is a highly prevalent condition worldwide, impacting up to 80% of individuals at least once in their lifetime. A critical gap in current prevention strategies is the lack of tools to accurately measure trunk posture and movement in real-world environments. Accurate identification of biomechanical risk requires information about movement intensity, duration, and frequency, yet traditional assessment methods rely on self-reporting or visual observation, which are time-consuming and prone to error. To address this gap, a wearable monitoring method, consisting of two Inertial Measurement Units, was designed to quantify risk exposure to the spine by measuring angular position …


Key Determinants In Electric Vehicle Charging Station Locations, Sania Pirouzi Jun 2025

Key Determinants In Electric Vehicle Charging Station Locations, Sania Pirouzi

Theses (2016-Present)

The growing adoption of electric vehicles (EVs) requires metropolitan areas to strategically plan the placement of charging infrastructure to support accessibility, efficiency, and sustainability. This study investigates key determinants for the optimal siting of EV charging stations, using Houston, Texas, as a case study. Through a comprehensive literature review and expert consultation, eight critical criteria were identified: land use type, population density, median income level of residents in the area, vehicle ownership rate in the area, young and middle-aged residents share in the area, flood risk, traffic density and proximity to major roads, and educational attainment of the residents in …


Ac-Induced Corrosion Of Cathodically Protected Pipelines: Experimental Study And Probabilistic Modeling, Yuhan Su, Emadoddin Majdabadi Farahani, Qindan Huang, Qixin Zhou Jun 2025

Ac-Induced Corrosion Of Cathodically Protected Pipelines: Experimental Study And Probabilistic Modeling, Yuhan Su, Emadoddin Majdabadi Farahani, Qindan Huang, Qixin Zhou

Civil and Environmental Engineering Faculty Research and Publications

This study investigated the effects of alternating current (AC) interference on pipeline steel under cathodic protection (CP). In a simulated solution, real-time electrochemical measurements and corrosion rate analysis were conducted on two steel types (C1018 and X60) under various levels of AC interference with CP. Due to the complexity of AC-induced corrosion, relying on the shift in DC potential alone cannot accurately demonstrate the corrosion behavior in the presence of AC interference. In fact, such an approach may mislead the predictions of corrosion performance. It is observed that AC interference reduced the effectiveness of CP and increased the corrosion rate …


Hyflex Engagement Tracking, Jane Courtney Jun 2025

Hyflex Engagement Tracking, Jane Courtney

Case studies: Digital Education

While authentic assessment methods can be easily implemented in modules that lend themselves to problem-based learning, quality assessment is harder to achieve in more technically rigorous subjects. For these modules, there has been an over-reliance to date on traditional exams. The move online due to COVID-19 made summative assessment of these technical subjects very difficult and also had many academics reporting reduced engagement in the online environment. However, in the technically rigorous Power Systems Analysis module, this challenge was approached as an opportunity to modernise and test online assessment possibilities. This was done through three mechanisms: Numbas*, Rubrics+ and Engagement …