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Bolin Symes Prosthetic
Get PDFThis project’s purpose is to design a comfortable prosthetic for an individual with a Syme’s amputation, which is a below-knee amputation that removes the foot from the leg at the ankle joint. The goal is to minimize the discomfort that is associated with the current prosthetic leg options for the client, Mr. Bolin, who has the Syme’s amputation. This project also seeks to improve mobility, quality of life, and activity levels of the client. The stakeholder for this project is Mr. Bolin. The final prototype performed successfully when worn by the client and passed comfort testing. Furthermore, COMSOL modeling of the device confirmed that it is strong enough to withstand maximum loading conditions with ease
An Exploratory Framework For Benchmarking Vehicle Miles Traveled (VMT) Estimates Associated With University Campuses
Get PDFAlthough vehicle miles traveled (VMT) has become the standard for assessing transportation related impacts in California, some have concerns that many VMT estimates are not properly grounded or informed by real world data, potentially resulting in flawed estimates and impact assessments. This is especially true of special generators, like college and university campuses, which have complex travel patterns distinct from that of the general public. This thesis attempts to resolve a significant disparity observed between two credible VMT estimates for Cal Poly’s campus wide VMT. As part of a campus master planning effort, a VMT estimate was produced in 2019 for an environmental impact report (EIR), using a travel demand model (TDM) based approach. This result was quite divergent from a prior 2018 estimate which used contemporaneous survey data (a data source often used to ground and calibrate/validate TDM results), leaving an approximate difference of 200 million VMT to be accounted for. In an attempt to address this disparity, this investigation considered three distinct analyses, including a quantitative assessment of variability of the 2018 travel survey estimate (via a bootstrap), an accounting of missing VMT not captured by the 2018 estimate, and a final comparison of the reliability and credibility of the 2018 and 2019 estimates based on both qualitative (scope and methodological issue of the estimates) and quantitative (benchmarking reported metrics) factors. Based on this investigation’s findings, although the disparity can be partially explained, a significant deficit of over 100 million VMT remained, suggesting the 2019 estimate may have overstated campus VMT and its impacts. It also suggests that campuses have significant VMT generating functions beyond the frequently studied commuter and residential travel behaviors. The lessons learned from this thesis provide a roadmap to improving future VMT estimates for college and university campuses as well as how regulators may approach setting appropriate analysis requirements and impact thresholds for these unique land uses
Empirical Support for Theoretical Conjectures
Get PDFThe PI is engaged in ongoing work on experiments designed to gather evidence for or against conjectures in one or both of two active areas in theoretical computer science: Markov chain Monte Carlo (MCMC) mixing times, and greedy approximation algorithms for combinatorial optimization problems. Research in the area of MCMC mixing seeks to prove theoretical upper and lower bounds on the mixing times—or convergence times—of random walk-based algorithms for sampling from various distributions. The PI has published three papers,,, in 2023, on this research, which were entirely theoretical. Two of these papers2,3—comprising the PI’s dissertation—left open a significant gap between upper and lower theoretical bounds, with some intuition in both cases that the lower bound is more likely correct. The PI is currently working with two MS students, who have implemented code to run a Markov chain for sampling binary trees. The PI has also worked previously with undergraduate students at the University of California, Irvine (UCI), implementing a Markov chain for sampling independent sets in trees. Further work extending this research may give evidence for or against theoretical conjectures regarding the mixing time of this chain. A separate theoretical line of research with opportunities for experiments lies within the broad area of approximation algorithms. We focus on the nearest-neighbor chain technique, which uses a stack-based data structure to speed up greedy algorithms. The PI co-authored a 2019 paper on new applications of the nearest-neighbo
Machine Learning Approach to Multi-scale Modeling of Granular Materials
No full textMachine Learning Approach to Multi-scale Modeling of Granular Materials aims to address the computational cost of multi-scale models by using machine learning to develop surrogate models for the behavior of granular materials. The discrete nature of these materials leads to complex bulk behavior dependent on the local physics of particles in crucial areas. The current literature has taken phenomenological or multi-scale approaches to capture these complexities. In phenomenological approaches, we assume the existence of explicit stress-strain equations, allowing for efficient simulations at the cost of uncertainty from the ’simple’ equations. For multi-scale approaches, simulations of individual grains are coupled with bulk-scale simulations, leading to more certainty at the cost of computation time. We will train a neural network on computational stress-strain data of granular materials to construct an accurate replacement of discrete-scale simulations
Significance of NonInvasive Endothelial Dysfunction and Other Cardiovascular Measurements in Various Communities
Get PDFThis pilot study aims to raise awareness of endothelial dysfunction in underrepresented communities, where cardiovascular disease is prevalent. By delivering educational presentations and materials, the study seeks to increase participants\u27 understanding and interest in endothelial dysfunction, potentially leading to proactive health behaviors. The results will inform future initiatives to enhance public knowledge and reduce the burden of cardiovascular disease in these communities.
In the future, there will also be a 3 vs 5-minute hyperemia study. Thirty participants without a history of cardiovascular disease will undergo testing using the Cordex SmartCuff™ device. If the three-minute hold proves to accurately measure endothelial dysfunction compared to the standard five-minute, it could reduce patient discomfort and improve the feasibility of clinical implementation, potentially refining cardiovascular risk assessments
Seismic Resilience of Timber Homes
Get PDFThe vast majority of residential buildings in California are wood-frame structures. A home is typically a very large investment for families, and damage to the home can be detrimental to a family’s economic success. Thus, reducing the economic impacts of an earthquake on residential timber housing is crucial. A full scale, two-story section of a residential timber house is in construction in the Parson’s Geotechnical and Earthquake Engineering Laboratory on the Cal Poly campus in San Luis Obispo, California. Once built it will be put through earthquake simulation tests on a shake table with various magnitudes of seismic activity. Next, an innovative self-centering dissipative system will be designed and implemented into the structure to evaluate the effectiveness of solutions such as these in reducing costly damages. Through experimental testing, we hope to inform future building codes and shift focus from life safety to performance-based analysis
Leveraging Tradespace-Exploration for A Senior Project Team Formation Application
Get PDFThis project revolves around the development of an app in MATLAB that leverages the VASSAR rule-based system and a genetic algorithm to form groups of teams for the Mechanical Engineering Senior Design project class. We leveraged the iterative design process to eventually attain a functional app with a reasonable runtime that works provided correctly formatted rulesheets describing student project preference and member preference
History & Evolution Of Plastic Mulching Technology: An Ethnography Of California Strawberry Plasticulture
Get PDFThis ethnography draws on key informant interviews and participant observation to produce a case study about plastic mulching as an important industry standard in specialty crop production. It documents the historic adoption and present role of plastic mulching technology in California strawberry production and addresses the characteristics of commercial standard management that inhibit the adoption of alternative mulching practices. It complements extensive research on strawberry pathology and fumigation, breeding innovations, fertilizer and pesticide treatments, and maximization of yields to incorporate participants’ lived experiences and knowledge of mulch origins, the technology adoption process, mulch benefits and drawbacks, the state of agricultural plastic waste (APW) management, and opinions on the future of the strawberry industry. A holistic assessment of plasticulture and the associated reliance on plastic mulch illuminates the ecological impacts of 20th-century agricultural commercialization. The reliance on technical synthetic inputs to expand control over soil systems has contributed to substantial anthropological pollution challenges and complicates the adoption of more benign alternative mulch types and management systems
Solubility Characterization of Organic Molecules for Aqueous Organic Redox Flow Batteries
Get PDFThe major obstacle to renewable energy sources is a lack of long-term energy storage capabilities. Energy produced during the day dissipates, leaving insufficient electricity for at night. The goal of the project is to design an Aqueous Organic Redox Flow Battery (AORFB) to act as long-term energy storage. Work has been done using machine learning to identify suitable compounds for the batteries. In this work there was no indication as to the aqueous solubility of the molecules; this controls the device’s energy storage capabilities. We used a machine learning model to determine the aqueous solubility of slightly more than 3000 compounds. An initial training dataset was made using NMR measurements to determine the aqueous solubility of ten* selected compounds. The trained dataset was used as validation data for the machine learning model described earlier and molecular dynamics simulations
Increasing Drift Capacity of Non-Ductile Concrete Shear Walls Through Confinement with Fiber-Reinforced Polymer Application
Get PDFThe seismic response and laboratory testing of pre-1980s reinforced concrete (RC) shear walls commonly exhibit undesirable concrete crushing and rebar buckling in the wall end-zones leading to a flexural compressive failure. The lack of ductility of these walls is attributed to low reinforcement ratios and absence of special boundary elements (SBE) as required by modern design code. Thus, the authors are proposing a fiber reinforced polymer (FRP) retrofit method to provide confinement to the end-zones of pre-1980s walls equivalent to that of an SBE.
Current industry applications of FRP have largely been for shear strengthening of RC beams, columns, and slabs. In contrast, the large-scale experimental study described in this paper aims to determine the effectiveness of FRP sheets
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and splay anchors as confinement of pre-1980s wall end-zones to increase the compressive strain capacity, delaying both concrete crushing and rebar buckling that precipitate the flexural compression failure. This is anticipated to increase wall drift capacity and potentially change the failure mechanism to one that is more ductile. Results from this study would demonstrate the feasibility of this FRP wall retrofit method to industry practitioners, especially attractive due to the relatively low-cost nature and minimally invasive implementation.
The Cal Poly research team previously conducted a pre-1980s wall test (Ostrom, 2018; de Sevilla & Luong, 2020) and modelling in PERFORM-3D (Doan & Williams, 2020). The wall specimen design discussed herein, R2-FRP, was proportioned from walls tested by Lu et al. (2017) to achieve a flexural compression failure, with predictions per ASCE 41-23 and Priestley’s (2007) Lumped Plasticity model confirming this target response