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Dynamic Modeling and Simulation of a Power Generation Steam Rankine Cycle for a Fluoride Salt-Cooled High-Temperature Reactor Nuclear Power Plant
No full textNuclear Fluoride Salt-Cooled High-Temperature Reactors (FHRs) have the potential to greatly improve nuclear technology in terms of safety and cost. By combining molten salt coolant technology from the Molten Salt Reactor (MSR) and TRISO fuel technology from the Very High Temperature Gas Reactor (VHTR), FHRs may operate at significantly lower pressures than Light Water Reactors (LWRs) and with a more robust fuel source that is excellent at containing fission products. However, as no FHR has been built, there are still many design questions to address. This thesis uses transient computer modeling and simulation to investigate how an FHR could potentially interface with a Rankine steam cycle to produce electricity, without freezing the molten salt. The simulation results show that implementing an intermediate loop raised the steam generator wall temperatures, on the salt side, from approximately 25°C below the salt freezing point to approximately 25°C above the salt freezing point. However, this margin drops to below zero at lower power levels (less than 50% reactor power). The model built in this research gives insights into various dynamics and applications of an FHR powered Rankine cycle, including the prevention of molten salt freezing, power ramp responses, and load-following
Itadakimasu: Recipes from Japanese American Internment Camps
No full textThis project presents a historical narrative told through the format of a cookbook, exploring the relationship between food, memory, and resilience during the Japanese American Internment of World War II. Using primary resources such as news publications from within the camps (Topaz Times,1943), historical interviews (Herzig, 1994), and secondary resources from an archival podcast (Campu, 2021) to highlight how food served as both a means of survival and an expression of identity under confinement.
The cookbook will combine recipes inspired by documented internment-era meals with stories and reflections gathered from interviews, archival materials, and community voices. Each section will contextualize the recipes within the lived experiences of Japanese Americans, illustrating how limited resources, creativity, and cultural values shaped daily life in the camps.
By blending design, storytelling, and historical preservation, this project aims to honor the legacy of those affected by internment and to promote cultural understanding through the universal language of food. The final deliverable will serve as both an educational artifact and a tribute to the perseverance of the Japanese American community
The Ethics of “Educational” Prison Tours
No full textResearch examining undergraduate student attitudes toward corrections suggests that criminal justice majors hold more punitive sentiments in comparison to their peers in other fields (Mackey & Courtright, 2000). While taking criminal justice courses can shift attitudes (Farnworth et al.,1998; Lane, 1997), how classes are taught can impact student sentiments. Experiential learning, for example, expands learning beyond the classroom (Stacer et al., 2017). Although disciplines have embraced this method, incorporations in criminal justice curricula sometimes manifest as tours of active correctional institutions (Smith et al., 2009) which can be extractive and dehumanizing for people who are incarcerated (C. Agans, personal communication, 2023; Dreisinger, 2016). Exploring alternatives, students in six criminal justice undergraduate courses during Fall 2023 and Spring 2024 were taken to Eastern State Penitentiary as part of a mixed methods project examining the impact of inactive prison tours on students’ perceptions of punitiveness, justice, and intersectionality. Students identified themes of injustice, racism, and frustration with the carceral system. Drawing from personal experiences with and reflections from active research on prison tours, we grapple with the ethics of engaging criminal justice students with the carceral system through inactive prison tours
A Comparative Evaluation of Feedback Strategies for Enhancing Student Software Test Suite Writing Outcomes
No full textBackground and Context
Software testing is a fundamental component of computer science education, forming the basis for students’ ability to ensure program correctness and reliability. Despite its importance, many students struggle to design test cases that effectively expose faults and achieve meaningful test coverage. Traditional instructional approaches often emphasize code coverage metrics such as line or branch coverage, but these metrics may not adequately capture the quality of student tests. Mutation analysis, which measures how well tests detect small, artificial faults (mutants) introduced into the program, offers a potentially richer measure of test effectiveness. However, little is known about how feedback based on mutation coverage affects student learning compared to more conventional coverage-based feedback. Objectives
This thesis investigates how different forms of automated feedback impact students’ underlying ability to construct effective test suites. Specifically, it examines whether exposure to mutation-based feedback or branch coverage feedback better improves students’ conceptual understanding and independent application of software testing principles. In other words, rather than asking which feedback produces stronger test suites during training, this study asks which feedback better helps students learn to become stronger testers. Method
To investigate these questions, a controlled experiment was conducted with students in undergraduate software engineering courses. Participants were randomly assigned to one of two treatment groups: one receiving automated feedback based on branch coverage, and the other receiving feedback based on mutation coverage. The study employed a pre/post-test design to measure learning gains independent of feedback exposure. In the beginning, all students completed a set of baseline (pre-test) problems in which they wrote test suites without receiving any feedback. During the intervention phase, each group practiced test writing while receiving their respective feedback type. Afterward, students completed a new set of problems (post-test) again without feedback, allowing direct measurement of how much their testing ability improved as a result of the practice sessions. Data from all three phases (pre-test, post-test, practice) was analyzed to assess changes in the correctness and completeness of the test suites, as well as additional statistical characteristics such as the quantity and redundancy of the test cases. Findings
The results showed that students who received mutation coverage feedback demonstrated a greater improvement in test-writing ability between the pre- and post-tests compared to those who received branch coverage feedback. Specifically, the mutation feedback group achieved a higher increase in fault detection and completeness, as well as a larger gain in mutation coverage from pre- to post-tests. During the practice phase, students receiving mutation feedback also wrote more tests on average than those receiving branch feedback, reflecting a more exploratory and fault-oriented testing approach. These outcomes suggest that exposure to mutation-based feedback encourages deeper reasoning about program behavior and more persistent refinement of test suites, leading to stronger transfer of testing skills beyond the feedback environment. Implications
Although results remain preliminary, this work contributes to the growing body of research on assessment and feedback in computing education by examining how different adequacy metrics can shape students’ testing practices. The findings are expected to inform instructional design decisions regarding the integration of advanced testing metrics, such as mutation analysis, into computer science curricula. Ultimately, this research aims to provide actionable insights for educators seeking to improve how software testing concepts are taught and assessed in undergraduate computer science programs
Cooking Made Clear: Accessible Cookbook Design for Older Audiences
No full textThis project explores accessibility-focused print and digital design features for older audiences within the cookbook and graphic communication industries. While cookbooks are widely produced, they rarely consider the physical, visual, and ergonomic experiences of aging users. Inspired by my grandmother’s 1980s church cookbook, I researched accessible design practices and communicated my findings through an infographic and a poster, highlighting features such as minimum 12–14 point body text, warm color palettes, high-contrast layouts, clear hierarchy, increased line spacing, simplified ingredient lists, columns, and lay-flat binding. I applied these learned features to several redesigned spreads from the original cookbook. This project demonstrates that thoughtful design, considering typography, layout, and usability, can make cookbooks more accessible, functional, and inclusive for aging audiences
Hand-Tracking and Extended Reality Interfa
No full textThis project explores the use of Extended Reality (XR) technologies to enhance human- robot interaction in industrial contexts. Building upon prior research in affective and cognitive state recognition during human-cobot collaboration, this study investigates how natural hand and head gestures, captured through Meta Quest passthrough mode, can be used to communicate human intent to a Universal Robotics e-Series collaborative robot. The XR system provides users with an immersive, real-world visual interface while tracking motion and position in real time. The captured gestures are interpreted through a custom software pipeline that integrates machine learning models and rule-based logic to trigger adaptive robot behaviors. This hands-free, intuitive control mechanism has the potential to lower barriers to cobot use, improve safety, and support both skilled and unskilled workers in manufacturing tasks. The project will prototype and evaluate an XR-based interface for gesture recognition, assess its usability and responsiveness in collaborative tasks, and explore its potential for integration with affective data gathered from complementary sensors. Ultimately, this work aims to contribute to the development of human-centric, adaptive robot systems that respond not only to physical commands but also to the human’s cognitive and emotional context
Modeling an Energy Management System for Residential Hybrid AC/DC Power Networks
No full textIn pursuit of supporting the global efforts in reducing carbon footprint and reliance on fossil fuels, this project seeks to continue the development of a hybrid AC/DC house prototype at Cal Poly State University. To enhance the power flow to DC loads, a dedicated 48 V DC bus will be constructed to replace the impractical multiple DC buses in the previous system. This iteration will also add a key feature that enables users to monitor real-time AC and DC powers. Another new functionality will involve the provision of a mix of latching and non-latching relays to switch between sources, thus ensuring that both AC and DC loads receive power. This new feature will further enable users to conveniently observe the system status and select which sources are utilized from a touchscreen. Other proposed improvements entail the integration of a control system with a Raspberry Pi and Arduino Nano and a touchscreen human-machine interface to control main components in the system. When fully completed, the hybrid AC/DC house will not only serve as a living laboratory to educate students and the community on residential electrical systems but will also serve as a demonstration site of a future Net-Zero Energy Home
Time-Domain Symmetrical Components for Detection and Analysis of Unbalanced Faults in Three-Phase Systems
No full textUnbalanced faults in three-phase power systems degrade performance, increase losses, and threaten equipment reliability. Traditional frequency-domain approaches using phasor analysis and symmetrical components offer valuable steady-state insights but respond too slowly for transient or rapidly changing conditions. This thesis investigates time-domain symmetrical components (ISCs) as a faster, physically interpretable method for detecting and analyzing unbalanced faults directly from instantaneous voltages and currents. Two ISC computation techniques were developed and compared: a polar-form method, applying one-third and two-thirds cycle time delays, and a rectangular-form method, which achieves equivalent phase shifts using only a quarter-cycle delay. Simulations in Microsoft Excel verified both methods, with the rectangular approach demonstrating superior accuracy and reduced latency. Experimental validation was performed using a mechanically coupled three-phase synchronous motor-generator system under controlled fault and imbalance scenarios. Results confirmed that time-domain decomposition reliably identifies fault types and sequence behavior consistent with theoretical expectations. These findings indicate that instantaneous symmetrical components can enable sub-cycle fault detection, supporting faster, more reliable protective relaying for modern, dynamically evolving power systems
Abiotic Stress Impacts on Macrophomina Root Rot and Nano-Encapsulated Citrus Oils to Control Fruit and Foliar Pathogens of Strawberry
No full textDisease remains one of the major constraints to the productivity and economic success of the California strawberry industry. The most important soilborne pathogen is Macrophomina phaseolina, causing Macrophomina root rot (MRR). The most economically significant airborne pathogens include Botrytis cinerea, causing Botrytis fruit rot (BFR), and Podosphaera aphanis, causing powdery mildew (PM).
Disease severity of MRR is highly dependent on environmental factors. Therefore, understanding which abiotic stressors contribute most to disease development is crucial for effective management. A two-year field experiment at Cal Poly, SLO (2024 and 2025) evaluated the effects of drought stress, two elevated chloride stresses, and high ECW stress on MRR development in two cultivars, Fronteras and Sweet Ann, that were artificially inoculated with M. phaseolina. Across both years, there was no significant treatment ´ cultivar interaction on final plant mortality (P = 0.557 and P = 0.391 for 2024 and 2025, respectively). In 2024 and 2025, treatment had a significant effect on final mortality (P = 0.008 and P = 0.024, respectively). Final mortality, averaged across both cultivars, was significantly higher in the drought stress treatment in 2024 (60.9%) and the high ECW treatment in 2025 (47.3%), when compared to the standard treatment (37.2 and 19.9% in 2024 and 2025, respectively). Cultivar also had a significant effect on final plant mortality in both years (P \u3c 0.0001 and P \u3c 0.0001, respectively). ‘Sweet Ann’ consistently had higher final plant mortalities when compared to ‘Fronteras’ across both years. These results highlight the importance of utilizing cultural management tools, including maintaining optimal soil moisture using soil tensiometers, avoiding the use of poor-quality irrigation water when possible, and planting disease resistant cultivars, to minimize disease severity.
Citrus essential oils have potential as biological controls that could limit crop losses due to foliar pathogens, reduce the use of synthetic fungicides, and slow resistance to major fungicide classes. However, low solubility and high volatility present barriers to practicality. Nano-encapsulation of essential oils offers a solution by improving dispersibility and retention of volatile bioactive compounds. Using commercially available citrus oil products that were nano-encapsulated (NE), preliminary trials were conducted to evaluate their efficacy against B. cinerea and P. aphanis across in vitro, in planta, greenhouse, and field settings at Cal Poly SLO. Treatments were pure citrus oils with the addition of an emulsifier, NE citrus oils containing 10% active ingredient (ai), and commonly used organic and conventional fungicides. Efficacy results were inconsistent across experiments. For the BFR experiments, NE citrus oils applied at 3 and 4% ai (v/v) significantly inhibited B. cinerea in detached fruit assays, when compared to the non-treated control (3%: P = 0.045; 4%: P \u3c 0.0001). However, no significant inhibition was observed in vitro or in the postharvest evaluations of the field experiment, which may be due to product degradation over time. In the detached leaflet assay for PM, treatment had a significant effect on disease incidence (P = 0.0178) and observed phytotoxicity (P \u3c 0.0001), but not disease severity (P = 0.0552). These results reveal limitations to the practicality of using NE citrus oils in commercial settings, including concerns of phytotoxicity and reduced product stability over time. Future work will evaluate the efficacy of NE citrus oils produced from Cal Poly harvested citrus against BFR and PM