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Technologies For Wearable Seizure Detection: A Systematic Review, Rhema Losli Jun 2024

Technologies For Wearable Seizure Detection: A Systematic Review, Rhema Losli

University Honors Theses

Knowing when a seizure occurred is helpful because this information can be used to evaluate the effectiveness of seizure interventions and possibly alert caregivers to emergency situations. The current practice for recording seizures outside of a hospital and without sensors is through keeping a self-reported seizure diary. This practice may be unreliable if the diary is not updated or the person having the seizure does not realize it is happening. Wearable seizure detectors aim to solve this problem by reliably recording when a seizure happened and either sending out an alert or storing the data for later analysis. In this …


Preservation Of Biomass In Underground Capsules Using An Open-Source Wireless Water Activity Sensor System: Capstone Review, Joshua Varughese Jun 2024

Preservation Of Biomass In Underground Capsules Using An Open-Source Wireless Water Activity Sensor System: Capstone Review, Joshua Varughese

University Honors Theses

This paper highlights the progression of a two-term senior capstone project in the ECE department at Portland State University. Sponsored by Dr. David Burnett from PSU's WEST Lab, the project aims to produce an affordable wireless monitoring system for water activity. The example scenario focuses on carbon sequestration where wood biomass is buried underground in enclosed capsules. For optimal sequestration, microorganisms capable of decaying the wood and releasing carbon back into the environment must be eliminated. Water activity, a key metric for measuring microbial activity, must be below 0.61 to prevent microbial survival. The system this project was designed for …


A Tessellation Of Engineers, Grace Jenkins Welsh Dec 2023

A Tessellation Of Engineers, Grace Jenkins Welsh

University Honors Theses

A capstone project is the culmination of what a student has learned while pursuing an undergraduate degree. A project of this magnitude requires a lot of time and dedication from every member of the team. This essay looks back at the experience of an electrical engineering student participating in the design of an auxiliary power and protection of a planned substation. The author describes the team's work, how they performed as a team, and their involvement with the professional sponsor and advisor. The author examines the experience with the goal of informing and encouraging prospective engineering students who may be …


Hybrid Photovoltaic + Battery Energy System Grid-Tied Converter Capstone Review Thesis, Archer Taylor Jun 2023

Hybrid Photovoltaic + Battery Energy System Grid-Tied Converter Capstone Review Thesis, Archer Taylor

University Honors Theses

Hybrid power converters present an opportunity to more efficiently harness energy from renewable sources. This paper reviews an undergraduate senior capstone project with the goal of designing and verifying the benefits of a hybrid converter, combining a photovoltaic array, battery energy system and a DC-AC inverter. The author recounts their experience throughout the 6 month period, detailing the research and design process followed by the prototype testing. Additionally, they reflect on the struggles of the capstone team and how to apply the learnings in the future.


Expanding Temperature Sensing For The Orion Bms 2, Samuel J. Parker Oct 2021

Expanding Temperature Sensing For The Orion Bms 2, Samuel J. Parker

University Honors Theses

Formula SAE (FSAE) is an annual collegiate design competition that takes place across the globe. Portland State University’s team, Viking Motorsports, was committed to designing an Electric Vehicle (EV) for the 2021 FSAE competition. The team designed a completely custom lithium-ion cell battery that is managed by an Orion BMS 2 battery management system. The FSAE rulebook requires a robust temperature monitoring system for any EV power supply. The Orion BMS 2 can only directly collect data from eight temperature sensors, which is not enough to meet FSAE regulation. However, the BMS can be configured to monitor many more sensors …


The Effect Of A Ferrite-Core Relay Vs. An Air-Core Relay On The Output Power Characteristics Of A Three-Coil Wireless Power Transfer System, Jakob L. White Aug 2021

The Effect Of A Ferrite-Core Relay Vs. An Air-Core Relay On The Output Power Characteristics Of A Three-Coil Wireless Power Transfer System, Jakob L. White

University Honors Theses

The purpose of this thesis is to determine the effect of using a ferrite-core relay on the output power characteristics of a three-coil, parallel-tuned, domino-resonator wireless power transfer (WPT) system in comparison to the effect of using an air-core relay in such a system. First, a general mathematical model is presented to describe both the ferrite-core-relay system and the air-core-relay system and to calculate their output power characteristics for seven different resistive loads at each of five different distance configurations between the coils. Next, experimental results are analyzed and compared to the mathematical results to confirm model accuracy. Finally, the …