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Role of Quartz Grain Size and Saturation on Fault Strength and Frictional Healing
Get PDFRocks near the Earth\u27s surface (less than 5 kilometers deep) often break and grind against one another to create crushed rock materials known as fault gouge. These fault gouges are filled with fragmented particles and broken rocks, which vary in grain size over time and space due to repeated earthquakes. This variation in grain size distribution along fault gouge can affect the strength of the fault, how it slips during an earthquake and how it \u27heals\u27 or recovers strength between earthquakes. Further, fault gouges often contain water from underground sources, which can influence how they slip. Previous studies have examined the influence of grain size, along with other factors such as pressure, stress, and surface roughness; however, isolating the role of grain size in controlling frictional stability and healing remains insufficiently explored. This study focuses on how the size of grains in fault gouge and the presence of water affect the fault strength and the way faults regain strength after a period of no movement. We performed a series of friction experiments on quartz material with four different grain sizes and studied how they responded to stress slipping under dry and water-saturated conditions at the same pressure found in the shallow parts of Earth\u27s crust.
The results suggest that gouges with smaller grains show sudden slip, a pattern similar to small earthquakes, where stress builds up and is then quickly released, whereas those with larger grains show increasingly stable sliding like creep. We also found that water makes faults more unstable and increases the rate at which they regain strength after slipping. These findings help us understand how faults behave and how earthquakes initiate, which can improve hazard assessments and earthquake prediction
An Exploratory Study of the Vertical SNARC Effect in Mayan Numerals: Effects of Language Transparency and Reading Direction
Get PDFThe Mayan numerical system, used by the ancient Maya people, is very different from the Western Arabic numerical system. Instead of being based on 10, it\u27s based on 20, and it uses dots and bars instead of the numbers 0 through 9. This study explored how people learn and understand Mayan numbers.
Participants took a 2.5-hour online course to learn Mayan numerals and number words. They were tested to see how quickly and accurately they could recognize and compare Mayan numerals. The results showed that people can learn the Mayan number system and use it automatically.
The study also looked at how people perceive the size of Mayan numbers and the direction that they’re read. People in this study associated small numbers with the top and large numbers with the bottom.
Overall, this research shows that learning the Mayan number system can change how we think about numbers and that our perception of numerical size may be influenced by how we interact with numbers
Assessing Public Satisfaction and Transportation Choices During Winter Road Maintenance: A Case Study of Utah
Get PDFWinter road maintenance is essential to keeping people safe and mobile during snowstorms. In Utah, where winter weather is a regular part of life, the Utah Department of Transportation (UDOT) plays a vital role in keeping roads clear and functional. While much attention is given to how roads are plowed and managed, there has been less focus on how the public experiences these efforts—and how the decisions to travel during storms are shaped by personal circumstances and perceptions.
This research sets out to understand two things: how satisfied people are with winter road maintenance, and what influences their transportation decisions during snow events. A survey of 550 Utah residents was conducted after two major winter storms in 2024. Respondents were asked about their travel behavior, satisfaction with snow and ice clearance, and how they received information during the storm. Their responses were then matched with local weather data collected from sensors across the state.
The results showed that satisfaction with snow removal efforts varies depending on the type of road and who is responsible. People were generally most satisfied with snow clearance on highways and major roads maintained by UDOT. However, they were less satisfied with snow removal on sidewalks, bike lanes, and near buildings—especially in areas where property owners or local governments are responsible.
Travel choices were also influenced by a range of factors. People who owned cars or were not employed were more likely to travel during storms, often for errands or leisure. Those who lived in certain regions, such as mountainous areas or neighborhoods with fewer resources, were more cautious or avoided travel altogether.
This study offers valuable insights that can help transportation agencies like UDOT make better decisions. By understanding who is traveling, why they are traveling, and how satisfied they are with current snow removal efforts, public agencies can improve operations and better communicate with residents. In the end, making winter travel safer and more reliable means listening to the public—and tailoring solutions to meet their diverse needs
Unveiling Insights From Complexity: Advanced Computational Techniques for High-Dimensional Medical Data
Get PDFHealthcare generates vast amounts of data daily, from genetic profiles to hospital records, but much of it remains untapped due to its complexity. This dissertation develops new computational tools to unlock this data’s potential, aiming to improve patient care and medical research. Five projects tackle different challenges: Project 1 creates Deep MAGIC, a method to fill in missing genetic and image data accurately, vital for understanding diseases like cancer. Project 2 analyzes how the COVID-19 pandemic disrupted surgeries, finding a 27% drop and temporary complication rises in 2020, guiding future crisis planning. Projects 3 and 4 study kidney disease trials, confirming reliable shortcuts to test treatments faster and cheaper. Project 5 introduces SIREN, predicting health outcomes with limited data, useful for early disease detection. Together, these tools turn raw data into practical solutions, paving the way for personalized medicine and better healthcare decisions
The Experience of Latine Parents During COVID-19: Coping, Support, And Wellness
Get PDFDocumentation status affects not just individuals, but entire family units. This project shares the voices of Undocumented Individuals and their Loved Ones (UnLOs), specifically Latine parents navigating multiple, overlapping stressors. Data was collected during a particularly challenging time marked by the COVID-19 pandemic and threats to the Deferred Action for Childhood Arrivals (DACA) program. Participants shared how they cope with stress, who they rely on for social support, how they practice wellness, and the type of community programming they would like to see more of. This research was possible through the collaboration between the Latinx Immigrant Health Alliance (LIHA) and United We Dream (UWD). LIHA is a group of scholars that focus on researching immigrant mental health to inform policy, and UWD is the largest immigrant youth-led network in the country. This dissertation, comprised of two studies, used a subset of the data, specifically focusing on those that identified as Latine and parents. The first study focused on how Latine UnLO parents coped with stress and who they relied on for social support. Many reported using acceptance, active coping, and positive reframing. Results also found that denial, substance use, and venting were associated with an increase in psychological distress. The second study explored how Latine UnLO parents practiced wellness, and if the number of wellness practices were associated with changes in psychological distress. Some of the most common wellness practices endorsed included physical activity, nutrition, and meditation. Results showed that the number of wellness practices had no significant relationship to psychological distress. However, participants expressed wanting to see more wellness programming from United We Dream, specifically around physical activity and nutrition. This research aimed to tell a story that highlights the strength and resilience of Latine UnLO parents, who continue to care for themselves and others, despite the policies and systems that often make life harder. As immigration debates and anti-immigrant attitudes continue in 2025, these findings serve as a reminder of what Latine UnLO parents have already done to survive, and how organizations can show up and support this community
Passive Precision Alignment for Thin-Panel Deployable Space Systems
Get PDFOptical satellite performance improves with increased surface area, which enhances light capture and sensor input. Deployable mechanisms allow satellites to remain compact during launch and expand in orbit but the large relative motion during deployment makes it difficult to achieve precision alignment in the final deployed state. This study focuses on designing passive hinges in rigid-panel origami-based deployable satellites for optical applications. A novel kinematic coupling method is developed, incorporating magnets, compact Lamina Emergent Torsional (LET) joints, and principles from Maxwell couplings. This system autonomously achieves alignment without motorized actuation. The design process involved iterative testing of ten two-panel hinge prototypes to identify the most effective designs. These were integrated into a degree-four vertex pattern (“bird’s foot”) for further refinement and ultimately applied to a full origami flasher pattern with 26 panels. The coupling accommodates the flasher’s non-rigid foldable nature while ensuring precise alignment, essential for optical applications requiring rigid panels. Additionally, all prototype configurations maintained an 8mm thickness, optimizing the stowed-to-deployed ratio for space applications. This study highlights the feasibility of precise kinematic couplings for small origami-inspired satellites and provides a foundation for advancements in deployable optical systems
A Proposed Process to Define and Collect Project Information for Cost Estimation of CubeSat Platforms
Get PDFCost estimation is a key element in the planning and execution of CubeSat mission, as it helps ensure that resources are used efficiently and that mission objectives remain aligned with technical and operational constraints. A solid technical baseline - one that clearly describes the system’s characteristics - is essential for developing reliable cost estimates and for establishing a shared understanding of the project among stakeholders. This paper presents the cost estimation process used at the ITA Space Center for CubeSat platforms. The method follows a structured, eight-step approach adapted from NASA and ESA standards. The steps begin with receiving the stakeholder\u27s request and understanding the project’s purpose. Next, a Work Breakdown Structure (WBS) is defined or obtained. In the third step, technical project information is gathered or reviewed. The fourth step involves building the cost model based on the chosen methodology. Step five focuses on collecting supporting data, which is followed by the actual cost estimation in step six. The seventh step addresses the analysis of risks and uncertainties. Finally, in the eighth step, the cost estimate is revised after design reviews to incorporate updates and changes. The paper focuses specifically on Step 3, where the technical baseline is defined. This step involves collecting and verifying project data, identifying system characteristics, and tracking technical milestones. This part of the process is particularly important for improving the accuracy and consistency of cost projections, especially for research and educational missions. To build this baseline, parameters such as satellite mass, mission type and duration, orbital profile, propulsion needs, power requirements, data rate, and attitude control specifications are collected. The parameters are selected and refined through discussions with subject-matter experts to reflect the specific needs of the CubeSats developed at ITA. An important aspect of this process is the close collaboration between the estimation team and the technical leaders. This ensures that the information used for cost modeling is up to date and reflects the actual system configuration. Additionally, the process considers the interdependencies between subsystems and external constraints, such as launcher compatibility and payload objectives, to improve overall estimate quality. The approach is illustrated through its application to SPORT; a space weather CubeSat developed at the ITA Space Center. The case study shows how Step 3 contributes to a more reliable cost estimate by grounding it in realistic and well-documented technical assumptions. This paper aims to contribute to the improvement of cost estimation practices for CubeSats and other small satellite missions, offering a process that is structured yet flexible enough to be adapted to projects with similar technical and operational characteristics
Space Payload for Inertial De-spin Efficient Effects (SPIDEE) for Reusable On-Orbit Attachment
Get PDFThe Space Payload for Inertial De-spin Efficient Effects (SPIDEE) is an electroadhesion-based general purpose in-space attachment payload ideally suited for docking, augmentation, mobility, and in-space assembly missions that does not require pre-preparation of the attachment surface.
Built around eTAPTM (electrical Thin Attachment Pad), SPIDEE supports missions to attach to, detumble, and provide space mobility to defunct satellites and/or rocket bodies. eTAP\u27s low power, reusability, and flexibility make it ideal as an all-purpose attachment and docking technology for the upcoming space challenge of reducing, reusing, and recycling in-orbit debris and/or assets. eTAP adheres to virtually all materials that are used in space, can conform to irregular surfaces, is low power, requires no substrate preparation, has enhanced performance in vacuum, is temperature agnostic, and leaves no residue.
Existing on-orbit attachment and/or docking methodologies tend to fall into two camps: either highly optimized for a single application (often requiring pre planned docking points), or large and complex enough to handle the wide variety of resident space objects (RSOs) that may be of interest. eTAP occupies a unique middle ground: it is a simple, flexible alternative that adheres to virtually any space material, providing unique and complementary advantages to alternatives based on optical sensing, magnetics, gecko technology, adhesives, and/or mechanical grappling.
Here we present data on dynamic testing representing satellite and rendezvous and proximity operations (RPO) docking interactions and modeling of forces and torques encountered during on-orbit operations and verification that eTAP can meet those requirements for a wide variety of target spacecraft masses and dimensions.
SPIDEE interfaces enable ease of integration to a wide variety of small satellite vehicles, from 3U CubeSats to ESPA-class servicing craft. Such a vehicle that can attach itself to others becomes a reusable small satellite platform—limited only by its available propellant—with the capability to cost-effectively address orbital debris remediation, as well as extend the life of operational satellites. In addition, the inclusion of other functionality as part of the payload, e.g. space domain awareness sensors, allows for mission augmentation on satellites never intended for it.
Additional mission applications enabled by eTAP include on-demand in-space assembly, refueling, and robotic end-effector augmentation
Spacecraft-Initiated Scheduling of Ground Stations: On-Orbit Results From TechEdSat-11
Get PDFThe commonplace practice of manually scheduling communications is challenged by complex and often unpredictable data needs of modern spacecraft. Automation has clear benefits to improve timeliness and efficiency of space communications. In this work we describe and experimentally demonstrate a suite of software which automates the process of scheduling contacts for satellite communications. Service is scheduled based on a spacecraft’s needs and contacts execute automatically without a human in the loop. Requests for service originate onboard the spacecraft, traverse a low-rate control channel to reach a terrestrial server, and are fulfilled by ground station assets. This work describes an experiment campaign conducted on the TechEdSat-11 technology demonstration CubeSat over five months starting in 2024. Our results from on-orbit testing demonstrate the feasibility of scheduling and executing communications service on a commercial ground station network without human intervention
Design of a Multi-Orbit SmallSat Constellation With Edge Computing for Space Weather Monitoring and Operational Forecasting
Get PDFSpace weather events in the 100–600 km thermosphere-ionosphere and magnetosphere impact satellites, Global Navigation Satellite System (GNSS), aviation, and power grids[1]. Current monitoring can be updated with sufficient spatial and temporal resolution and global coverage to meet World Meteorological Organization (WMO) standards, especially where solar activity accelerates orbital decay and radiation risks. This poster proposes addressing this with a hybrid constellation of 24 SmallSats employing advanced edge computing and multi-orbit observation, targeting operational readiness by 2032