Clutch Analysis and Design for the Wildcat Pulling Team Quarter Scale Tractor Drivetrain

The University of Kentucky (UK) Wildcat Pulling Team competes in the annual ASABE International Quarter Scale Tractor Student Design Competition. In 2022 the team placed 3rd overall in the competition, missing 1st place by 23 points. The loss in points was due to the clutch subassembly having issues related to maneuverability, manufacturability, and serviceability. The goal of this project was to redesign the 2022 tractor’s drivetrain for the new 2023 competition tractor. Background research was conducted on three types of clutches: manual, electric, and centrifugal. The electric clutch and centrifugal clutch with manual override were tested to determine their viability for the application. The electric clutch does not allow for easy maneuverability due to its high starting acceleration by instantaneous connection of the magnets. Changing the duty cycle and ramp duration could decrease the starting acceleration; however, the rider still experienced significant starting whiplash, and there were concerns with durability. The centrifugal clutch automatically engages at 2700 rpm threshold and is inactive below that threshold. A hydraulic throwout bearing was used to manually override the engagement threshold on the centrifugal clutch to engage at lower speeds. This configuration showed positive results, as no significant power loss was observed, and the configuration worked as anticipated without any wear on any of the parts. Test results indicated that the centrifugal clutch configuration was the better choice for this application. The final design is a belt-driven system with two cantilevered shafts connected on the backplate with a removable cover, improving access for serviceability

Solar and stellar flares and their connection

This thesis focuses on bridging the gap between solar and stellar physics through the study of flares. Solar flares are the most powerful explosions in the solar system and many stellar flares have been observed to be orders of magnitudes larger. However, is not yet known if these phenomena are formed through the same physical process. In this thesis we explore their common origins through a detailed case study of a solar flare and a robust statistical analysis of stellar flares with bespoke observations. Using data from the Swedish Solar Telescope, a detailed study of a solar flare associated with a filament eruption and jet was compared with advanced 3D MHD simulations. This amalgamation of observation and theory allows for a complete picture of the event including the pre-flare magnetic structure and the resulting kinematics of the jet post eruption. Overall, this study aims to characterise the physical environment capturing many evolutionary properties of the event providing a unique perspective on eruptive phenomena on the Sun. With regards to stellar flares, observational data from both K2 and TESS are used to conduct a statistical analysis on flares from both low mass and solar-type stars. As a result of this, no relationship between the rotational phase of stellar flares and starspots is present. This was unexpected as there is a well-established relationship between solar flares and sunspots. This result yields potential implications for how the magnetic field in fully convective low mass stars is generated. Possibly, this result implies the surface of these stars is more complex than the Sun. Furthermore, groups of rapidly fast rotating low mass and solar-type stars were discovered to exhibit very little flaring activity. This is unusual, as rotation is linked to a star’s dynamo mechanism and so faster rotating stars are expected to show higher levels of activity. This research has raised new questions surrounding the underpinning mechanisms driving stellar flares. In an effort to address this the solar 3D MHD simulation is scaled up to replicate flare energies seen in the observed stellar flares. This comparative analysis allows for the exploration of the flare mechanism and potential magnetic structure on these stars, which will be a subject of future research, in order to explain such high energy flares

Probing the origin of stellar flares on M dwarfs using TESS data sectors 1–3

Detailed studies of the Sun have shown that sunspots and solar flares are closely correlated. Photometric data from Kepler/K2 has allowed similar studies to be carried out on other stars. Here, we utilize Transiting Exoplanet Survey Satellite (TESS) photometric 2-min cadence of 167 low-mass stars from Sectors 1 to 3 to investigate the relationship between star-spots and stellar flares. From our sample, 90 per cent show clear rotational modulation likely due to the presence of a large, dominant star-spot and we use this to determine a rotational period for each star. Additionally, each low-mass star shows one or more flares in its light curve and using Gaia Data Release 2 parallaxes and SkyMapper magnitudes we can estimate the energy of the flares in the TESS band-pass. Overall, we have 1834 flares from the 167 low-mass stars with energies from 6.0 × 1029 to 2.4 × 1035 erg. We find none of the stars in our sample show any preference for rotational phase, suggesting the lack of a correlation between the large, dominant star-spot, and flare number. We discuss this finding in greater detail and present further scenarios to account for the origin of flares on these low-mass stars

Philanthropic Sourcing, Diligence, and Decision Making: An Equity-Oriented Approach

These are times that demand courageous giving to provide essential fuel for social change efforts in areas ranging from public health and the environment to inequality, racial equity, and much more. The ever-rising scale and urgency of the challenges facing our communities and our planet are a clarion call for funders to take giant leaps forward.Sourcing and diligence processes are at the heart of funders' ability to meet the moment. By "sourcing," we mean finding and elevating nonprofits and initiatives to fund, while "diligence" refers to the vetting process donors conduct before making a contribution. Together, sourcing and diligence are the means to an important end: providing information for making decisions on giving. But that's not all—sourcing and diligence processes can also help donors meet and build trust with those who are leading the hard and ongoing work of social change. In addition, they can energize donors about what is possible, helping them see how their support contributes to an arc of impact that is larger than any one individual's reach.In this article, we offer practical sourcing and diligence guidance for donors who want to increase their contributions to social change efforts—whether they are just getting started or have been at this work for decades. This information will help donors make their grantmaking more inclusive and equitable, and, importantly, it will help donors get started, "learn while doing," and improve over time

Exploring the Impact of Youth Engagement in Social Media: Shifting the Boundaries of Harm and Criminality in the Digital World?

This paper employs a qualitative approach to understanding the impact of youth engagement in social media. The expansion of social media has occurred alongside this. By applying a zemiological lens to the analysis of this study, from the early stages of data collection it was evident that ongoing changes to UK legislation around vulnerability caused, and perpetuated by, the online space remained a grey area for concern. Specifically in terms of who holds responsibility for safeguarding young people when engaging with a growing variety of information sources through social media. A particular interest area within this, for the researcher, is the harm posed to young people in the offline world, when engaging with image-based networks, filtered imagery and diet culture through social media platforms; an area that stands at the heart of various ongoing UK parliamentary debates, at the time of writing this paper, urging for vast legislative shifts. The discoursal change of the Online Safety Bill to the Online Harms Bill, in its drafting stages, by the UK Government creates a clear pathway for this paper to pursue a zemiological analyses of current strategies to protect and criminalise the distortion of reality by the online world, under ‘influencer culture’. This paper concludes that despite an expansive period of evidence collection by the UK Government, to understand the lived experience of vulnerable social media users, more time and effort is needed to make such legislative amendments an impactful, and collaborative process

Normalisation of Online Hate: Trolling, Diet Culture and Filtered Lifestyles

Lauren Doyle provides an oversight into a paper she presented to the BSC Hate Crime Network in May 2023 exploring the normalisation of online hate, diet culture and filtered imagery. Key words: Harm, social media, hate, diet culture, regulatio

Spectroscopic studies of arcade flares with EIS and EVE

This thesis investigates Doppler velocities in the flares SOL2014-03-29T17:48 and SOL2011-02-16T07:35 through methods of spectral analysis in EUV spectral data from Hinode/EIS and SDO/EVE. This was to understand plasma flows and compare measurements made with both instruments. Chapter 1 gives detailed background information introducing the Sun and solar atmosphere providing the beginnings to understand the mechanisms behind solar flares. Various spectral lines are also discussed including different properties of the line and appearances in both EIS and EVE data. In Chapter 2 Hinode/EIS data is introduced discussing the raw data itself, how EIS makes its observations along with spectroscopic analysis carried out. Intensity and Doppler velocity maps are also provided for several emission lines during both flares. Chapter 3 then discusses EVE data including all of the analysis techniques applied to the raw data and the steps taken to obtain Doppler velocities. Results were then given as velocity-time plots of various emission lines showing the changing Doppler velocity as the flare progresses. Chapter 4 then brings all of this together and describes the methods used to transform the EIS data into a comparable form to EVE. Direct comparisons of data from both instruments is then made and presented

In A Pickle: A Marketing Analysis of Images and Textual Descriptions on Food Packages and How They Influence College Students\u27 Grocery Purchases

The reason for confusion in grocery stores is the fact that many of the same types of food products are being marketed with different labels. Many packaging labels contain keywords such as “organic,” “farm fresh,” and “all natural.” Some products incorporate the use of images such as a picturesque farm or a “happy” cow. Using data collected from the surveys of 349 college students, this study examines student choices of food products based on organic and non-organic and brand and generic foods. Variables also examined include sex, health, and living arrangements. The results of this study can help provide an understanding about the mindset of the average college student while shopping at the grocery store. Based on the results there is evidence that students are significantly more likely to choose food products that are non-organic and generic. Based on the five variables used, sex and concern for nutritional value were the most significant in predicting a student’s purchase of brand and organic food products, while body mass index, frequency of looking at nutritional facts labels, and living arrangement were not significant