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Investigating the Effects of Vitamin D Supplementation on Juvenile Dogs: A Preliminary Study
Full text linkMentor: Dr. Scott Jerome; This study evaluated the effects of vitamin D3 supplementation in juvenile dogs over 90 days. Despite prior evidence supporting supplementation, no significant differences in serum 25(OH)D levels were found across baseline, supplementation, and washout phases. Vitamin D content in commercial dog food and supplements was also analyzed to inform dietary guidelines
Microbial Response to Permafrost Thaw and Coalescence
Full text linkMentor: Dr. Mario Muscarella; Permafrost thaw is a major concern for the Arctic and sub-Arctic regions because it can emit large amounts of stored carbon into the atmosphere as carbon dioxide or methane. These greenhouse gasses (GHG) are controlled by microbial activities. Permafrost thaw will let the frozen and active layer soils mix, allowing the microbial communities to form new mixtures of organisms and organic compounds. With increasing temperatures, this could be vital to understand how microbes impact gas flux and their soil ecosystem
Measuring Erosion Rates of Rocks to Quantify Their Carbon Capture in Alaska
Full text linkMentor: Dr. Florian Hofmann; Igneous rocks are capable of capturing CO2 from the atmosphere and permanently storing it. Data on this process in Alaska is sparse. This study aims to quantify the erosion rate of igneous rocks in Alaska and assess the impact on long-term carbon storage
Electric power regulation for a novel riverine hydrokinetic energy conversion system
Full text linkThesis (M.S.) University of Alaska Fairbanks, 2025Transportation of diesel fuel used to produce electricity for Alaska remote communities is highly expensive. Thus, people living in those remote areas pay a high rate for electric energy compared to the national average cost. The availability of renewable energy resources may help to minimize these high expenses. As many rural Alaskans live near rivers, hydrokinetic energy could be used as a renewable source of electric power. This renewable resource, if successfully harvested, has immense potential to help power Alaska remote communities and significantly reduce electric energy costs. This project aims to investigate the implementation of an energy conversion system to harvest riverine power by utilization of a novel hydrokinetic energy harvesting system through field testing and modelling. An electrical power generator, specifically a permanent magnet synchronous generator (PMSG), was selected to be used for mechanical-to-electrical energy conversion within a low-speed range. Unregulated electric power produced by the generator was rectified and filtered to produce smooth DC power. A maximum power point tracking (MPPT) current controller was implemented in the Simulink® environment to demonstrate how to extract the maximum power available at the generator output under different water velocities and load conditions.Alaska Center for Energy and Power, University of Alaska Fairbanks College of Engineering and Mines, Advanced Research Projects Agency-Energy (ARPA-E), U.S. Department of Energy Award Number DE-AR0001444Chapter 1: Introduction -- 1.1 Research objectives -- 1.2 Hydrokinetic energy -- 1.3 Generator selection process -- 1.4 Power conversion and regulation -- 1.5 Harmonics -- 1.6 Thesis organization. Chapter 2: Literature review -- 2.1 Generators -- 2.2 Power conversion -- 2.3 Maximum power point tracking control -- 2.3.1 Tip speed ratio control -- 2.3.2 Power signal feedback control -- 2.3.3 Hill-climb search control -- 2.3.4 Optimal torque control -- 2.3.5 Comparison of maximum power point tracking controllers -- 2.4 Microgrids -- 2.5 Summary of literature review. Chapter 3: Field tested system -- 3.1 Tanana River Test Site (TRTS) selection and field test location -- 3.2 TRTS on-water testing infrastructure and research barge setup -- 3.3 Floating generator housing and hydrokinetic turbine design -- 3.4 Gearbox -- 3.4.1 Precision planetary gearbook -- 3.4.2 Features and parameters of gearbox -- 3.5 Permanent magnet synchronous generator (PMSG) and specifications -- 3.5.1 Permanent magnet synchronous generator (PMSG) -- 3.5.2 Torque-speed curve of permanent magnet synchronous machine (PMSM) -- 3.5.3 Specifications of permanent magnet synchronous generator -- 3.5.4 Generator housing configuration -- 3.6 Panel board configuration and electronic components -- 3.7 DC load bank testing for HECS -- 3.8 Acoustic doppler current profiler (ADCP) -- 3.9 Fish monitoring and impact assessment on turbine performance -- 3.10 Debris interaction test and evaluation of turbine durability -- 3.11 Evaluation of shore-based deployment system performance -- 3.12 Performance analysis of a solid shaft connection in place of a flexible torsional cable -- 3.13 System's data collection. Chapter 4: Model development and simulation -- 4.1 System block diagram -- 4.2 Hydrokinetic turbine (HKT) model -- 4.2.1 Tip speed ratio versus power coefficient -- 4.2.2 Schematic diagram of hydrokinetic turbine (HKT) model -- 4.3 Gearbox -- 4.4 Permanent magnet synchronous generator (PMSG) -- 4.5 Three-phase rectifier (AC-DC) -- 4.6 Filter capacitor design calculations -- 4.7 Boost converter -- 4.7.1 Boost converter inductor design calculations -- 4.7.2 Boost converter capacitor design calculations -- 4.8 Calculation of adjusted load resistance -- 4.8.1 System diagram for adjusted load resistance analysis -- 4.8.2 Analysis of equivalent and adjusted load resistances in system simulation -- 4.9 Development of MPPT current controller -- 4.9.1 Investigation of hydrokinetic turbine characteristics for MPPT implementation -- 4.9.2 Parameters setup for MPPT current controller -- 4.10 System simulation with MPPT current controller. Chapter 5: Results and analysis -- 5.1 Field test measurements -- 5.1.1 Mechanical measurements -- 5.1.2 Electrical data measurements -- 5.2 System simulation with constant water velocity -- 5.2.1 Electrical frequency -- 5.2.2 Pulse width modulation (PWM) signal -- 5.2.3 Input and output current, voltage and power of boost converter -- 5.2.4 System simulation results -- 5.3 System simulation with variable water velocity -- 5.3.1 Water velocity setup -- 5.3.2 Variation in frequency -- 5.3.3 Variation in pulse with modulation (PWM) -- 5.3.4 Variations in current, voltage, and power. Chapter 6: Conclusions and future work -- 6.1 Conclusions -- 6.2 Future work -- 6.2.1 Future development scope in the field test -- 6.2.2 Future development scope in simulation model -- 6.3 Final thoughts
Blackwater wolf
Full text linkThesis (M.F.A.) University of Alaska Fairbanks, 2025Rural Kentucky’s cultural and geographical landscapes in the early 1990s serve as the foundation for Blackwater Wolf, a novel that examines the intersections of place, identity, and love. The story follows two young women as they navigate a same-sex relationship in a conservative community, where societal pressures and personal doubts ultimately strain their connection. Separated by circumstance and time, they reunite seventeen years later when the mysterious disappearance of a local child brings them back together. The child’s claim that a monster inhabits the shadow of Black Mountain becomes both a literal mystery and a metaphorical lens through which the protagonists—and the reader—explore memory, trauma, reconciliation, and the boundaries of monstrosity. By blurring the line between reality and the uncanny, Blackwater Wolf seeks to interrogate the ways deeply rooted cultural myths shape personal identity while challenging readers to reconsider what it means to belong, to heal, and to transform in the face of fear and uncertainty
Data Submission Package for Manuscript 'Progress on the world's primate hotspots and coldspots: Modeling ensemble Super SDMs in cloud-computers based on digital citizen-science Big Data and 200+ predictors for more sustainable conservation planning'
No full textDescribing where distribution hotspots and coldspots are located with certainty is crucial for any science-based species management and governance. Thus, here we created the world’s first Super Species Distribution Models (SDMs) including all primate species and the best-available predictor set. These Super SDMs are conducted using modern Machine Learning ensembles like Maxent, TreeNet, RandomForest, CART, CART Boosting and Bagging, and MARS with the utilization of cloud supercomputers (as an add-on option for more powerful models). For the global cold/ hotspot models, we obtained global distribution data from www.GBIF.org (approx. 420,000 raw occurrence records) and utilized the world’s largest environmental predictor set of 201 layers. For this analysis, all occurrences have been merged into one multi-species (400+ species) pixel-based analysis. We quantified the global primate hotspots for Central and Northern South America, West Africa, East Africa, Southeast Asia, Central Asia, and Southern Africa. The global primate coldspots are Antarctica, the Arctic, most temperate regions, and Oceania past the Wallace line. We additionally described all these modeled hotspots/coldspots and discussed reasons for a quantified understanding of where the world’s primates occur (or not). This shows us where the focus for most future research and conservation management efforts should be, using state-of-the-art digital data indication tools with reason. Those areas should be considered of the highest conservation priority, ideally following ‘no killing zones’ and sustainable land stewardship approaches if primates are to have a chance of survival.Ye
Alaska Misdemeanor Assault Arrest Rates: 1985-2022
Full text linkThis fact sheet presents Alaska misdemeanor assault arrest rates per 100,000 Alaska residents from 1985-2022
Dendrochronology and the Mile 11 Landslide in Wrangell, Alaska
Full text linkMentor: Dr. Margaret Darrow; My goal was to find out if trees caught in the landslide had any clues of slope movement before the landslide occurred. To do this, I sanded tree cookies, performed a LiDAR change detection analysis, and consulted with experts to better understand the Mile 11 landslide
Does microclimate variation in tundra ecosystem drive microbial community assembly?
Full text linkMentor: Dr. Mario Muscarella; In this project, I will analyze soil samples from a polygonal tundra landscape to study microbial communities and their metabolic activities, focusing on how microclimate variation drives the composition taxa present and their metabolic activity
Diverse Habitats Support Resilience in Rubus idaeus Pollination and Fruit Production
Full text linkMentor: Dr. Katie Spellman; I studied the pollination biology of Rubus idaeus as it relates to climate change, agriculture, and subsistence practices in interior Alaska