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Integrated Actuator
Get PDFThis Final Design Review document outlines the senior project design that we, a team of four mechanical engineering students at California Polytechnic State University, are developing for Charlie Refvem, a lecturer in the mechanical engineering department. The final design has undergone significant modifications since the Critical Design Review, such as a redesigned vertical shaft, material changes, and the incorporation of belt tensioners. These redesigns are thoroughly discussed in the context of testing and assembly error resolution.
The document outlines the detailed steps for the production and testing of the design verification prototype. This includes the procurement and manufacturing of components, the assembly and operation of the mechanism, and the tests conducted to verify that our design meets our sponsor’s specifications. The document also discusses the challenges with the current design and suggests ways of improving the design for future iterations
Complex Dimensions Of 100 Different Sierpinski Carpet Modifications
Get PDFWe used Dr. M. L. Lapidus\u27s Fractal Zeta Functions to analyze the complex fractal dimensions of 100 different modifications of the Sierpinski Carpet fractal construction. We will showcase the theorems that made calculations easier, as well as Desmos tools that helped in classifying the different fractals and computing their complex dimensions. We will also showcase all 100 of the Sierpinski Carpet modifications and their complex dimensions
Mate Choice and Sexual Conflict in a Livebearing Fish
Get PDFEavesdropping occurs when a receiver extracts information from an interaction without directly engaging with the signaler. Eavesdropping has been shown to be an effective way of evaluating the quality of potential mates and their abilities in male-male competition, without having to directly interact with them, thereby reducing energy costs and mating harassment. Girardinus metallicus is a livebearing poeciliid fish endemic to Cuba whose mating system is dominated by mating harassment in the form of sneak copulations, persistent displaying, and male-male aggression. G. metallicus has a male specific polymorphism in both melanin coloration and behavior. Males with melanin coloration are known as black morphs. Black morph males show persistent displaying and higher aggression, whereas plain morph males, the most common morph, do not have pronounced melanin patches and mate solely by sneak copulation. Plain morph males exhibit lower levels of aggression than black morph males.
In Chapter 1, we created groups consisting of a female and two males differing in body size and exposed them to dichotomous choice tests of female preference before and after the females witnessed the males interacting with each other. We hypothesized that: 1) male morphological traits are sexually selected via female choice in G. metallicus because these traits indicate quality; 2) female G. metallicus eavesdrop on male aggression to make mate choice decisions because aggression may indicate the quality of the male and his propensity to harass females; and 3) male size classes differ in behavior and morphology (saturation, brightness, and gonopodium size), consistent with other poeciliid studies showing that body size influences phenotype and that these traits are intercorrelated. We predicted 1) females will associate more with more colorful males, males with shorter gonopodia, and the larger male, before eavesdropping on male-male interactions, after, or both; 2) females will spend more time associating with males that subsequently delivered more chases and bites to a competitor male; and 3) larger males would be more active, more persistent in mating attempts, be more aggressive, and have a larger gonopodium size, and greater saturation and brightness of their posterior, ventral, and dorsal body regions. We found that females prefer to associate with males whose body regions are highly saturated, before eavesdropping on the two males interacting, but females did not prefer saturation after eavesdropping. We also found that females had a preference for smaller gonopodia relative for a males’ body size after eavesdropping. We also found that as male size increases, gonopodium length is proportional to their standard length. This study is the first to show female preference for coloration traits within any morph of G. metallicus, suggesting that plain morph males are not as plain to females as their name suggests.
Individual animals consistently vary in the average level of behavior exhibited across a range of contexts, which is also known as personality. Behavioral syndromes are correlations among personalities grouping them together. Personality traits have implications for mate choice, fitness, and predator avoidance. In Chapter 2, we addressed behavioral traits and personality in females and whether they influence how males respond to different degrees of boldness, activity, and aggression. We assessed female latency time to emerge from a refuge chamber, activity level, and aggressiveness to another female, on three successive days. We then quantified the degree of mating harassment each female experienced, when tested with a male. We hypothesized the following: 1) female G. metallicus exhibit personality across behavioral contexts (risk, activity, and resource competition), consistent with findings in other poeciliids including male G. metallicus; 2) the rank orders of boldness, activity, and aggression are positively correlated, consistent with other poeciliid studies that found evidence for behavioral syndromes; and 3) female personality traits mitigate male harassment because females that exhibit those personality traits are better at avoiding/retaliating against male harassment. We predicted that: 1) behavioral traits (latency time to emerge, boxes entered, and chases, bites, and fin flares delivered to a female competitor) measured within each context would be repeatable; 2) female rank orders of boldness, activity, and aggression personalities would be positively correlated with each other; 3) that larger females would experience less harassment; and 4) when females directly interact with a male, females that are bolder, more active, and more aggressive (bites and chases delivered to the male) are better able to mitigate male harassment. We found support for the hypothesis that some behavioral traits are repeatable in females; however, we found no evidence for behavioral syndromes. We found evidence to suggest that females that are less bold and less aggressive received less mating harassment from males, possibly because those females are of lower quality and not as attractive to males. Our most novel finding in this study was that activity and aggression were both consistent behavioral traits in females, and therefore constitute personalities; however, these personalities did not have a correlation grouping them together into a behavioral syndrome. Maybe there is a tradeoff: good females are bold and aggressive and get more food, but receive more mating harassment, whereas bad females are submissive and get less food, but avoid mating harassment
An IMC Plan for the Blue Dolphin Company, a Local Nonprofit
Get PDFAlan Godley\u27s journey into marine preservation began as a dock boy, a role that brought him face-to-face with the environmental impact of boat cleaning practices. Witnessing the washing of harsh chemicals into the ocean and waterways fueled his environmental consciousness. Years later, he founded the Blue Dolphin Company in 1989, an “organization focused on furthering the awareness of whales and dolphins, and all marine life … [supporting] the rehabilitation and release of marine mammals and other wildlife”. Over the three decades, Mr. Godley has operated this nonprofit and small business, leveraging educational initiatives to inform people of all ages about relevant restoration projects. The funding for these efforts is sourced through website sales, vending opportunities, and direct donations. However, as technology and social media advanced, the Blue Dolphin Company encountered challenges in adapting to contemporary business practices, leading to struggles in maintaining its presence in the evolving marketplace. In the late 1990s, Blue Dolphin lost its brick-and-mortar establishment. Since then, sales have primarily emanated from an aging website that has not kept pace with modern design and functionality standards. This challenge prompted a reevaluation of business strategies and a recognition of the potential benefits that embracing contemporary practices could bring. My introduction to the Blue Dolphin Company occurred at the San Luis Obispo swap meet, where Mr. Godley showcased T-shirts featuring endangered animals and bumper stickers adorned with humorous political commentary. The palpable passion he exuded for his work profoundly resonated with me, and from a public relations standpoint, it became evident that there was 3 untapped potential for the business to thrive in the contemporary world with a strategic and modernized approach. This encounter marked the initiation of efforts to revitalize and elevate the Blue Dolphin Company\u27s presence in the digital age
An Empirical Evaluation of Neural Process Meta-Learners for Financial Forecasting
Get PDFChallenges of financial forecasting, such as a dearth of independent samples and non- stationary underlying process, limit the relevance of conventional machine learning towards financial forecasting. Meta-learning approaches alleviate some of these is- sues by allowing the model to generalize across unrelated or loosely related tasks with few observations per task. The neural process family achieves this by con- ditioning forecasts based on a supplied context set at test time. Despite promise, meta-learning approaches remain underutilized in finance. To our knowledge, ours is the first application of neural processes to realized volatility (RV) forecasting and financial forecasting in general.
We propose a hybrid temporal convolutional network attentive neural process (ANP- TCN) for the purpose of financial forecasting. The ANP-TCN combines a conven- tional and performant financial time series embedding model (TCN) with an ANP objective. We found ANP-TCN variant models outperformed the base TCN for equity index realized volatility forecasting. In addition, when stack-ensembled with a tree- based model to forecast a trading signal, the ANP-TCN outperformed the baseline buy-and-hold strategy and base TCN model in out-of-sample performance. Across four liquid US equity indices (incl. S&P 500) tested over ∼15 years, the best long-short models (reported by median trajectory) resulted in the following out-of-sample (∼3 years) performance ranges: directional accuracy of 58.65% to 62.26%, compound an- nual growth rate (CAGR) of 0.2176 to 0.4534, and annualized Sharpe ratio of 2.1564 to 3.3375. All project code can be found at: https://github.com/kpa28-git/thesis-code
2nd Annual Girls Build Summer Academy: Apprentice I Service Project
Get PDFAt Cal Poly construction management department’s second annual Girls Build Summer Academy for high school-aged girls, first year academy participants completed a service learning project to enhance the well-being of the turtles and tortoises at a turtle and tortoise sanctuary. In this week-long day camp, which exposed girls to various career paths within the architecture, engineering, and construction industry, girls learned all industry aspects from volunteers, construction management alumni, and camp leaders, and were provided the opportunity to safely learn and apply building construction techniques. Throughout the week, they learned about tools, materials, and safety, and applied those skills to complete both individual and team service learning projects. First year participants worked together to construct a tiered planter with a trellis for the Turtle and Tortoise Sanctuary of Arroyo Grande. This project fostered teamwork, adaptability, and problem solving. This paper describes the project’s goal and the lasting impact on the girls and the lives of the turtles and tortoises. The girls left with new skills and more excitement that they could have a future in the construction industry, with some wanting to explore a career in trades once they finished high school as a result of their camp experience
Documenting Tetranychus Urticae and Lygus Hesperus Resistance Status in California Strawberries
Get PDFThe resistance status of Tetranychus urticae Koch and Lygus hesperus Knight sourced from California strawberry fields was evaluated in laboratory bioassay experiments. Adult female T. urticae sourced from a miticide naïve population were exposed to a range of miticide active ingredient concentrations mixed with acetone in contact bioassay experiments. LC50 concentrations for the active ingredients fenpyroximate, abamectin, bifenazate, and spiromesifen as well as LC90 concentrations for the active ingredients fenpyroximate, abamectin, and bifenazate were derived from this susceptible population. A total of ten field populations of T. urticae, five from the Santa Maria growing region and five from the Ventura/Oxnard growing region, were exposed to these concentrations and mortality response was compared with the susceptible population to determine the resistance status of T. urticae on a per-field basis.
Resistance detection occurred less often in the LC50 concentration groups compared to their respective LC90 concentrations. Resistance to the LC50 concentration of spiromesifen could not be detected in any field population. Resistance to the LC90 concentrations of fenpyroximate and abamectin was detected in three field populations from Santa Maria and four populations from Ventura/Oxnard. Resistance to the LC90 concentration of bifenazate was detected in three populations from Ventura/Oxnard and in no populations from Santa Maria.
Lygus hesperus were exposed to formulated products registered in California strawberries after being separated into three groups based on life stage. Instars one through three were considered small, instars four and five were considered large, and winged individuals were considered adults. The small and large groups were exposed to the maximum field labeled rate of Rimon® (a.i. = novaluron). Adults were exposed to the maximum field labeled rate of Actara®, Brigade®, and Sivanto®, the active ingredients of which are thiamethoxam, bifenthrin, and flupyradifurone respectively. A total of 14 field populations were screened for resistance, six collected from the Santa Maria growing region in 2021, and eight collected in 2022, five of which came from the Santa Maria region, and three from the Salinas/Watsonville region. Resistance was detected by comparing the mortality response of an insecticide naïve population of L. hesperus and field collected populations in residual laboratory bioassay experiments. Resistance to Rimon® in the small group was effectively detected in all populations in 2021 and 2022. Resistance to Rimon® in the large group was detected in four populations in 2021 and five populations in 2022. Resistance to Actara® and Brigade® was effectively detected in all populations in 2021 and 2022. Resistance to Sivanto® was effectively detected in four populations in 2021 and two of three populations in 2022. A full submersion assay was utilized for the second half of Sivanto® trials in 2022 since mortality response of the susceptible population was low in the residual group. Five of five populations tested with the modified assay were considered effectively resistant
Design and Validation of a Wearable SmartSole for Continuous Detection of Abnormal Gait
Get PDFResidual gait abnormalities are common following lower limb injury and/or stroke and can have several negative impacts on an individual’s life. Without continuous treatment and follow up, individuals can be prone to chronic pain as abnormal gait may lead to non-physiological loading of the musculoskeletal system. The current industry gold standard for diagnosing abnormal gait requires specialty equipment that is generally only available at designated gait facilities. Due to the inaccessibility and high cost associated with these facilities, a wearable SmartSole device to continuously detect abnormal gait was proposed. A previous iteration of the SmartSole was unable to properly detect abnormal gait and also experienced fracturing throughout the 3D printed body. In this present study, sensor placement and material selection were reconsidered to address these limitations. The objective of this study was to determine if a redesigned SmartSole could identify events of abnormal gait through validation and verification testing against the industry standard force plates. In total, 14 participants were selected for gait studies, 7 with pronounced gait abnormalities (e.g. limps), and 7 with physiological gait. Parameters of interest included stance time, gait cycle time, and the ratio of the force magnitudes recorded during heel strike and toe off. Results indicated that the SmartSole was effective at determining overall event timings within the gait cycle, as both stance and cycle time had strong, positive correlations (left stance: r = 0.761, right stance: r = 0.560, left cycle: r = 0.688) with the force plates, with the exception of right foot cycle time. The sole was not effective at measuring actual values of events during gait as there were weak correlations with the force plates. Furthermore, when comparing parameters of interest between the injured and non-injured sides for test participants with gait abnormalities, neither the SmartSole nor the force plates were able to detect significant differences. The inability of the sole to accurately collect force magnitudes or to detect abnormal gait leads to the conclusion that additional sensors may need to be implemented. Future iterations may consider placement of additional sensors to allow for a “fuller picture” and the inclusion of other types of sensors for improved, continuous tracking of gait abnormalities
Active and Visual Methods for Teaching Nonrectangular Reinforced Concrete Beams
Get PDFNonrectangular cross sections are a common occurrence in reinforced concrete design typically taking the form of flanged beam sections, circular columns, and square or rectangular columns subject to biaxial bending. Instructors typically introduce the theory behind nonrectangular beams using two-dimensional sketches of flanged sections. Students can struggle to visualize the examples when presented in two dimensions; deciphering the multiple resultant compressive forces and their corresponding moment arms are particularly difficult. This paper presents an overview of nonrectangular beam theory and select active learning methods along with three specific examples used by the authors to teach nonrectangular beams in an undergraduate reinforced concrete design course. The first method is a simple problem-based learning example to dissuade students from “plug and chug” calculations using improper equations; the second method illustrates three cases for a traditional flanged T-beam section using physical three-dimensional models; and the third method uses virtual three-dimensional models to derive the depth of the equivalent stress block and corresponding nominal flexural strength for various cross sections. Each description provides the reader with the best practices to implement the respective technique. Lastly, the authors provide some lessons learned from their past implementations. The overall goal is to provide educators with examples to simplify the presentation of nonrectangular beams theory
Assessing The Resilience Of Mycorrhizal Networks Following Central Tree Removal
Get PDFMycorrhizal networks (MNs), or the networks of fungal mycelia that connect plants to each other, are vital in contributing to the well-being of ecosystems. They not only assist in the transport of nutrients across an ecosystem, but also help protect an ecosystem from disease and adverse conditions. However, more research into these networks is needed and modelling these networks as graphs can help us achieve this. By applying centrality analysis and performing k-core partitioning on these networks, we are able to identify the trees that are most important and central to a MN and observe the effects of removing these trees. We also perform random partitioning on these networks and compare the results to the k-core partitioning results. We found that these networks are fairly resilient to the removal of a single keystone individual, but this can disrupt the interconnectedness of a MN in a dry (xeric) moisture regime. We also found that these networks are less resilient to k-core partitioning. In a network of trees divided up by age cohorts, the maximal k-core subgraph contained a mix of trees that mostly belonged to older cohorts and were linked to one specific fungal genet. This could influence conservation efforts for not only a few older trees, but also some younger trees and potentially specific fungal genets. When removing the maximal k-core subgraphs for networks in dry (xeric) and moist (mesic) moisture regimes, the network became disconnected for the xeric graph and still somewhat connected for the mesic graph. So, mycorrhizal networks could possibly be more resilient to this k-core partitioning in an area where the soil is moist rather than dry