100039 research outputs found
Sort by
MOSAIC - A Modular Orbital Satellite for Advanced Innovation and Curriculum
No full textThis paper presents MOSAIC (Modular Orbital Satellite for Advanced Innovation and Curriculum), an open-source, modular satellite platform designed to advance space technology education and to accelerate satellite mission design. MOSAIC is a demonstrator satellite, or “mocksat” that leverages commercial off-the-shelf (COTS) components and a modular hardware ecosystem to make satellite technology accessible, affordable, and adaptable for educational institutions and research teams. This work details the technical architecture of MOSAIC, its potential educational benefits, cost analysis, and open-source philosophy, demonstrating its goals to democratize access to satellite engineering and foster the next generation of space professionals
Preliminary Scale Analysis of Formation Flying for Direct-to-Device Communication Using Ultra-Small Satellites
Get PDFDirect-to-Device (D2D) communication in satellite constellations is attracting attention for enabling direct links to mobile terminals without large ground antennas. This approach could extend mobile coverage and support future Cyber-Physical System (CPS) use cases, such as connected vehicles and IoT sensing.
To overcome data rate limitations caused by the small antenna size on individual satellites, we propose a formation-flying system that constructs a large-aperture phased array antenna [1]. Our analysis shows that a swarm of tens of thousands of pico- or femto-class satellites can meet the required link budget, enabling broadband D2D communication with practical
Enhanced SmallSat Agility via CMG-Controlled Bus
Get PDFAs the small satellite industry continues to grow, mission teams continue to look for opportunities to maximize data collection and thus revenue per spacecraft. Many satellites in this class rely on well-understood traditional reaction wheel technology to provide precise pointing and re-orientation capabilities. Control Moment Gyroscopes (CMGs) offer a quantum leap in re-orientation performance as compared to reaction wheels (RW) but are typically utilized on much larger and more complex spacecraft outside the classification of small satellites. While Blue Canyon Technologies’ (BCT) RW-based spacecraft continue to provide high performing on-orbit pointing performance, BCT spacecraft actuated with a cluster of CMGs and coupled with existing optimal attitude trajectory software will provide a significant improvement in spacecraft agility with capability to maneuver between more ground targets per orbit. BCT offers two variants of CMG, the CMG-8 and CMG-12, that can be outfitted inside a new variant of BCT spacecraft, controlled by BCT GN&C systems, or sold stand-alone to provide this improvement in small satellite agility
Climate-Adapted Forests in Arizona and New Mexico: An Overview of Forest Composition and Review of Common Garden Studies
No full textThis website is an overview of forest composition and review of common garden studies in Arizona and New Mexico. Includes Common Garden Studies Research, Forest Types, and Literature Review
Understanding Hydroclimate in the Contiguous United States: Roles of Temperature vs Precipitation and Subtropical Pacific Warming
Get PDFThis study investigates the physical drivers and mechanisms of hydroclimate variability across the Contiguous United States (U.S.), using a combination of observable data, reanalysis data, land modeling, and coupled climate model experiments. One of the major findings is that the historic 2021 drought event across the Western U.S. was primarily driven by a severe lack of precipitation rather than increased temperatures. The study further finds that anthropogenic forcing has substantially increased the risk of this extreme drought by approximately 26 times relative to a world without the influence.
Additionally, the study reveals that the Pacific Meridional Mode (PMM) characterized by sea surface temperature (SST) anomalies in the subtropical Pacific plays a key role in shaping the historically observed Dry-West, Wet-East summertime precipitation pattern over the Contiguous United States (CONUS). A robust zonal dipole pattern was identified by the association between the PMM index and precipitation, with negative correlations over the Western U.S. and positive correlations from the Coupled Model Intercomparison Project Phase 6 (CMIP6), indicating that the PMM may serve as a useful predictor of summertime precipitation variability in the U.S.
Chapter 4 explores how global climate model simulations from the Community Earth System Model (CESM) version 1.0 respond to changes in Pacific SSTs, including those tied to the PMM. Results show that SST anomalies confined to the PMM region successfully reproduce the canonical PMM structure and trigger large-scale atmospheric circulation. However, the CESM simulations also exhibit a shift in PMM-related moisture transport from the subtropical Pacific into the Western U.S. and precipitation, relative to the observations. These findings highlight the importance of improving climate models to more accurately represent tropical rainfall and atmospheric dynamics, which are essential to advancing drought predictions and water resource planning
Soil Health on Utah\u27s Farms and Ranches
Get PDFThe term soil health has gained popularity in agriculture due to prolonged droughts, rising food costs, and the growing public concern for sustainable and organic practices. Soil health practices can offer solutions to all of these pressures. This thesis provides Utah\u27s farmers and ranchers with quantifiable data on implementing soil health practices in Utah\u27s unique climate. It presents the first two years of on-farm trial results on yield and quality after implementing various soil health practices on five categories of crops: corn, mixed hay, alfalfa, produce, and dryland grain. Over a two-year period, none of the soil health practices resulted in a statistically significant yield reduction across any site, indicating that these approaches can be implemented without short-term yield penalties and lays the groundwork for longer-term evaluation of their benefits.
In addition, this thesis also presents a guide for growers for interseeding cover crops into corn based on regional research. Interseeding is most effective when done between the V4–V6 corn growth stages. To increase the interseeded cover crop biomass, wider corn row spacing could be used because it improves light availability for cover crop growth, but it also may reduce corn yield. Reducing corn planting density can improve conditions for interseeded cover crops without impacting corn yield. Drilling cover crops with high-clearance or modified equipment often resulted in the best cover crop establishment and fall biomass. Proper timing and type of irrigation significantly affects cover crop success. Extra water may be needed post-harvest to promote fall cover crop growth and maximize benefits. Multiple studies from Utah, Idaho, and other states show that interseeded cover crops have no significant negative impact on corn grain or silage yield, provided nutrient requirements are met. While cover crops carry upfront costs, they can become profitable especially when grazed by livestock
Population Analysis of Cyanobacteria in Rotating Algal Biofilm Reactors
Get PDFAlgal biofilms have numerous applications in wastewater treatment and bioproduct production. The Sustainable Waste-to-Bioproducts Engineering Center at Utah State University is working to develop rotating algal biofilm reactors (RABRs) to remove excess nitrogen and phosphorus from wastewater effluent while producing biomass for downstream production.
Genetic analysis of algal biofilms on various RABRs was performed to gain improved understanding of the biofilm populations. This analysis focuses on a pilot-scale RABR and how it compares to several other RABRs. Additionally, old methods of genetic analysis filtered out important cyanobacterial populations. A new method was developed to identify the cyanobacteria within the biofilms.
Analysis indicated higher diversity in the pilot RABR and trickling filter biofilms. Furthermore, I showed that the pilot RABR had consistent diversity over time. Several key biofilm organisms were identified including Synechococcus, Chlorella, and multiple varieties of Proteobacteria. I also developed an analysis using a software package called DADA2 that was better at detecting cyanobacteria within the algal biofilms, however the analysis did have lower taxonomic specificity
The Effect of Voter Education on Behaviors in Ranked Choice Voting
Get PDFThe appeal of ranked choice voting has led to its recent meteoric rise throughout America, leading to adoption in a number of cities and a handful of states, but some critics and political scientists worry about its higher difficulty potentially leading to more errors and undesirable behavior. Utilizing an experiment, I find that a short voter education video is all that is required to reduce rates of errors and ideologically inconsistent behavior, while finding null results for undervoting, possibly due to its low occurrence in the sample.
As ranked choice voting’s adoption is considered in each election cycle for jurisdictions ranging from small towns in Utah to statewide adoptions nationwide, this research clarifies the nature of some of the potential drawbacks of the reform. This may alleviate some concern for jurisdictions who are considering ranked choice voting if those jurisdictions are willing to commit resources to voter education
Unwritten Rules: Black Utahns’ Experience With De Facto Segregation in Utah, 1940-1965
Get PDFThis thesis examines life in Utah during the Jim Crow era, utilizing oral history interviews with African Americans who lived in the state between 1940 and 1965. The interviewees selected for this project describe their personal experiences with housing, employment, public spaces, medical assistance, and education discrimination
Distal Impact of Learning Trajectories on Motivational Factors in Second Language Acquisition of Adult English Learners
Get PDFLearning a foreign language is a long-term process sustained by learners’ motivation, self-efficacy, and self-regulation. While prior research has established that past performance influences these motivational factors, overlooking the impact of past performance on current motivational constructs. This dissertation explores how past learning performance impact current motivational factors. Using a person-centered approach, three subgroups were identified as latent learning profiles within the sample population based on their performance features: the high-performing early peak profile, the stable profile, and the rising profile. Regression models were conducted to evaluate the extent to which latent learning profiles predicted motivational variables. The results showed that the learning trajectory group membership had significant effects on motivational variables scales, and the subscales of self-efficacy, intrinsic motivation, self-regulation, and cognitive strategies. These results were compared to results of regressions using individual test scores and the aggregate mean of test scores as independent variables to evaluate which method best captured the association between past learning performance and current motivational states. Results revealed that performance trajectories provided a more comprehensive understanding of learners’ motivational dynamics. These findings hold implications for designing interventions that enhance learner motivation, self-efficacy, and self-regulation strategies by addressing the interplay between performance trends and motivational factors over time