Physical Sciences and Mathematics Commons^™

Farey Recursion And Hyperbolic Dehn Filling, Jose Ebenezer Martinez

Graduate Student Theses, Dissertations, & Professional Papers

In this work, we present a solution to William Thurston's edge gluing equations for Dehn fillings of hyperbolic 3-manifolds. This is done for triangulations that involve the layered solid torus. Our approach uses Farey recursive functions, and we present a Farey recursive function that provides a solution to the gluing equations for any hyperbolic Dehn filling admitting a triangulation by the layered solid torus. We provide examples that demonstrate our solution for multiple 3-manifolds, and study the roots of the corresponding Farey recursive polynomials. As an additional application of our solution, we provide a formula for the complex length of …

A Tale Of Two Working Landscapes, Sage C. Sutcliffe

Graduate Student Theses, Dissertations, & Professional Papers

No abstract provided.

Characterizing Mountainous Bedrock Groundwater Systems Across Gradients In Topography And Lithology In Western Montana, David L. Baude

Graduate Student Theses, Dissertations, & Professional Papers

Mountain aquifer groundwater systems remain one of the least understood hydrologic systems in upland hydrology. In this study, we aim to characterize bedrock groundwater system dynamics and bedrock-saprolite interactions across a variety of landscape positions and lithology. We investigate groundwater hydraulics, recharge temperature and elevation, residence times, and bedrock recharge rates across two mountainous headwater catchments in west central Montana. We used a suite of environmental tracers (³H, CFCs, SF₆, and ⁴He) and residence time distribution models to estimate groundwater mean residence times over a range of timescales from decades to millennia. Tracers were sampled …

Coalescence: A Carnivore Coexistence Curriculum That Braids Indigenous & Western Ecological Knowledge Into A Relevant And Experiential Learning Opportunity For Youth, Stephanie Anne Barron

Graduate Student Theses, Dissertations, & Professional Papers

As grizzly bears (Ursus arctos horriblis) begin to reoccupy more of their historic range, and as humans and large carnivore populations continue to increase, incidences of human carnivore conflict are on the rise. A decolonial curriculum designed in collaboration with the Confederated Salish and Kootenai Tribe’s wildlife biologists stands to increase awareness of Indigenous ecological knowledge and teach youth about the importance of coexistence with carnivores. Additionally, this project could greatly influence youth perceptions of grizzly bears and other large carnivores. This research project examines the development and implementation of a carnivore coexistence curriculum for youth that is guided by …

Hydrogeomorphic Response To Flooding In Northern Yellowstone National Park, Zachary P. Deluca

Graduate Student Theses, Dissertations, & Professional Papers

Understanding and predicting flood-induced geomorphic change, and the relative influences of fluvial forces and valley-bottom geometry on system response, are persistent quandaries in geomorphic process studies. We combine field surveys, remote sensing, and hydraulic modeling to assess the hydrogeomorphic effects of historic flooding in northern Yellowstone National Park (YNP) in a variety of channel configurations. We compare impulse, a metric that incorporates a flow duration threshold based on threshold channel theory, grain size, channel-bed slope, and flood depth and stream power estimates with hydrogeomorphic response. Measurements of pre- and post-flood active-channel width change in aerial photos captured geomorphic response associated …

Drought Conditioning Conifer Seedlings For Post-Fire Management And Climate Change Adaptation, Anna C. Ross

Graduate Student Theses, Dissertations, & Professional Papers

Increased frequency, severity, and duration of drought and increased wildfire severity are together impacting forests of the western U.S. To encourage forest ecosystem resilience to these changing disturbance regimes, there is a need for novel silvicultural techniques that develop seedlings capable of establishing in hotter and drier climates. We evaluated the morphological and physiological effects of a drought conditioning treatment applied in a greenhouse on second- year ponderosa pine (Pinus ponderosa), western white pine (Pinus monticola), and western larch (Larix occidentalis) seedlings. Treatments included a well-watered control (75% of container capacity) and a water-limited …

Meta-Analysis Of Scent Detection Canines And Potential Factors Influencing Their Success Rates, Molly Marie Jaskinia

Graduate Student Theses, Dissertations, & Professional Papers

Objective: This is a meta-analysis focused on the success rates of scent detection canines and potential factors that could influence their accuracy. A series of statistical analyses were conducted to determine if certain demographic factors, such as the dog’s gender, age, and breed, have an effect on a scent dog’s accuracy during a search. Or if more circumstantial factors, like the dog’s level of experience in scent work, the type of target scent, and their handler’s awareness of the target’s location, affect the outcome of the search.

Materials and Methods: A dataset was created from 37 different articles consisting of …

Applications Of Transfer Learning From Malicious To Vulnerable Binaries, Sean Patrick Mcnulty

Graduate Student Theses, Dissertations, & Professional Papers

Malware detection and vulnerability detection are important cybersecurity tasks. Previous research has successfully applied a variety of machine learning methods to both. However, despite their potential synergies, previous research has yet to unite these two tasks. Given the recent success of transfer learning in many domains, such as language modeling and image recognition, this thesis investigated the use of transfer learning to improve vulnerability detection. Specifically, we pre-trained a series of models to detect malicious binaries and used the weights from those models to kickstart the detection of vulnerable binaries. In our study, we also investigated five different data representations …

Evaluating The Sensitivity Of Crustal Deformation To Bedrock Hydrology In A Mountain Watershed, Brett J. Oliver

Graduate Student Theses, Dissertations, & Professional Papers

We evaluate the sensitivity of Earth's elastic deformation to groundwater hydraulic diffusivity using coupled groundwater and elastic deformation models. Seasonal changes in terrestrial water storage cause deformation to the Earth’s crust and deeper interior that is within the observational capacity of GPS instruments. We couple finite difference groundwater simulations with geodetic forward models of crustal displacement to investigate the ability of geodetic deformation to constrain bedrock hydrologic properties. We use MODFLOW-2005 to simulate seasonal changes in groundwater flow and storage, and then use the LoadDef elastic deformation model to forward model surface displacement caused by the change in terrestrial water …

The Birds And The Trees: Quantifying The Drivers Of Whitebark Pine Decline And Clark's Nutcracker Habitat Use In Glacier National Park, Vladimir Kovalenko

Graduate Student Theses, Dissertations, & Professional Papers

Whitebark pine (Pinus albicaulis), recently listed as threatened under the Endangered Species Act, is in steep decline in Glacier National Park, Montana, USA due to the non-native pathogen Cronartium ribicola, causal agent of the fatal disease white pine blister rust. A sample of the park’s population suggests that approximately 70 percent of whitebark pines have died, while 65 percent of the remaining trees are infected. Using landscape and climate variables, we show how geographic location, elevation, aspect, solar radiation, relative humidity, and snowpack interact with tree diameter to affect mortality, disease incidence, cone production, and regeneration. We also examine how …

Synthetic Aperture Radar Observations At Salar De Pajonales, Chile, Michael A. A. Mcinenly

Graduate Student Theses, Dissertations, & Professional Papers

Remotely sensed microwave radars provide the spatial and temporal coverage needed to improve our understanding of the relationship between moisture content and salt pan mineralogy and, ultimately, climate variability. Moisture content in the surface and near-surface crusts found in salt pan environments, such as salt pan, has a significant impact on the backscatter values recorded by synthetic aperture radar (SAR) systems. This is because moisture affects the dielectric constant and surface roughness of the saline surface, which in turn influences the amount of electromagnetic energy reflected back to the SAR sensor. Changes in backscatter values are attributed to seasonal and …

Assessing The Impact Of Parallel Burnout Fires On Flank Rate Of Spread, Erik Borke

Graduate Student Theses, Dissertations, & Professional Papers

The effects of flank-parallel suppression fires on the local rate of spread (ROS) of freely burning headfires through fully cured homogeneous grass fuels are assessed. Data sets include: one thermal image stack of a prescribed burn recorded by drone, and a suite of simulation experiments carried out in Wildland Urban Interface Fire Dynamics Simulator (WFDS). A new approach to computing ROS, curvature proxy driven normals to convex polylines, was developed to carry out this analysis. ROS time series depicting flank acceleration of the prescribed burn and simulation experiments, observable under coarse and fine directional classification schemes respectively, are the primary …

Evaluating The Relative Influence Of Soil Water Potential, Soil Moisture, And Vapor Pressure Deficit On Semi-Arid Vegetation Dynamics, Kayla R. Jamerson

Graduate Student Theses, Dissertations, & Professional Papers

Knowledge of vegetation’s response to soil water availability and atmospheric demand is critical to understanding the impact of climate change on semi-arid ecosystems. However, limited field-based research has been conducted to assess the relative importance of these drivers and previous research has simplified the assessment of soil water availability by relying on soil volumetric water content (VWC) as a primary control on plant growth, which, as opposed to soil water potential (Ψsoil), does not account for the effects of soil texture on plant available water. To address these gaps, we compared remotely sensed indicators of vegetation response to field based …

Climatological, Hydrological, And Economic Analysis Of Agriculture In Montana And The Western U.S.A., Zachary H. Lauffenburger

Graduate Student Theses, Dissertations, & Professional Papers

Many studies have addressed the impact of climate on agriculture; however, fewer studies addressed how farmers adapt to climate change, to what extent implementation of adaptation strategies mitigates economic losses or alters the hydrologic system. Analyses of how historical climate affected not only farmer decision making, but also the economic and hydrological consequences of farmers’ adaptations to climate variations, and projections of the spatiotemporal climatic regimes at finer regional scales are critical for aiding in actionable climate change adaptations. This dissertation helps fill knowledge gaps on the impacts of climate change in rural regions of the agricultural western U.S.A. and …

Investigating Elastic Deformation Induced By Surface Loads On Planetary Bodies, Ashlesha Khatiwada, Hilary Martens, Donald F. Argus

Graduate Student Theses, Dissertations, & Professional Papers

Planetary bodies, including the Earth, deform when there is a redistribution of surface load. In this thesis, I conduct three independent projects related to surface loading, two of which investigate methods related to the modeling of surface loading and one which seeks to catalog the displacement responses of other planetary bodies to a surface load.

The first project aims to compare four methods for modeling the elastic loading response of the Earth: a homogeneous, non-gravitating, half-space method; a homogeneous, gravitating, spherical method; a homogeneous, non-gravitating spherical method; and a radially stratified gravitating spherical method. Many studies have focused on computing …

Beaver Dam Analogs (Bdas) Alter Carbon Pools, Fluxes, And Concentrations Of Intermountain Headwater Streams, Hilary Schultz

Graduate Student Theses, Dissertations, & Professional Papers

Beaver dam analogs (BDAs) have emerged as a climate adaptation and restoration strategy for water resource management in the drought-prone Western U.S., yet the focus has been on their influence on water quantity, overlooking effects on broader ecological components. By increasing water residence time and facilitating sediment retention, BDAs have the potential to influence carbon pools, fluxes, and concentrations. To examine the influence of BDAs on instream and riparian organic C and trace gases, we studied three intermountain headwater streams restored with BDAs two years after restoration during the summer of 2021. We found that there were subtle differences in …

Displacement, Place Attachment, And Other Characteristics Of Anglers On The Yellowstone River, Zachary L. Jones

Graduate Student Theses, Dissertations, & Professional Papers

Yellowstone River has seen increasing recreational use as Montana has grown and out of state visitation has increased, leading to some locals voicing concerns of crowding. River recreation, as with many outdoor recreational activities, has participants that may be considered to be sensitive to crowded conditions and place a high value on solitude. Considering these perceptions, there is reason to believe that these participants may change their river use patterns if or when the perceived level of crowding exceeds their tolerance thresholds. Further, monitoring efforts conducted at river access sites often do not fully capture users that are already displaced …

Evaluating The Use Of Environmental Tracers To Reduce Conceptual Model Uncertainty Of Hydrogeologic Models, Andrew Nordberg, Jon Graham, W. Payton Gardner

Graduate Student Theses, Dissertations, & Professional Papers

Environmental tracer concentrations for CFC12, SF6, and tritium are used in groundwater simulations to assess the ability of these tracers to reduce conceptual model uncertainty due to uncertainty of a site’s geologic and recharge characterization. The resulting groundwater simulations are characterized by site-specific hydrologic and geologic data, and with coordination from a field team with years of knowledge about the site. First-order (conceptual) uncertainty is directly addressed by using a stochastic modeling approach for spatial variability of the proposed subsurface configurations. Simulations of environmental tracer concentrations and water levels are used to assess six alternate conceptual models that are based …

1-D Crustal Seismic Velocity Models For West-Central And Western Montana, Courtenay Duzet

Graduate Student Theses, Dissertations, & Professional Papers

In seismically active areas with infrequent, large-magnitude earthquakes, high-quality seismic data are critical for determining high-resolution, accurate seismic velocity models. Here, we present a new local-scale seismic velocity model for the crust in west-central Montana as well as a new regional-scale seismic velocity model for the crust and upper mantle across broader western Montana. The new models are constrained by phase arrivals from several passive seismic networks, including the University of Montana Seismic Network (UMSN), the Montana Regional Seismic Network (MRSN), the Advanced National Seismic System (ANSS), temporary deployments by the United States Geological Survey (USGS), and the USArray Transportable …

Sensitivity Of Lidar Derived Fuel Cells To Fire Modeling At Laboratory Scale, Anthony Albert Marcozzi

Graduate Student Theses, Dissertations, & Professional Papers

Computational models of wildfires are an important tool for fire managers and scientists. However, fuel inputs to wildfire models can be difficult to represent with sufficient detail to be both computationally efficient and representative of observations. Recent advances in fuel mapping with airborne and terrestrial laser scanning (LIDAR) techniques present new opportunities to capture variation in fuels within a tree canopy and on a landscape. In this paper, we develop a technique for building 3D representations of vegetation from point clouds created by Terrestrial Laser Scans (TLS). Our voxel based approach can be extended to represent heterogeneous crown fuels as …

Relationships Between Water, Sediment, Basal Resources, And Aquatic Insects In A Mine-Contaminated River On A Longitudinal And Habitat Patch Scale, Chelsea A. Wisotzkey

Graduate Student Theses, Dissertations, & Professional Papers

It is well established that aqueous exposure and dietary exposure both lead to the accumulation of metals and metalloids in aquatic organisms living in a contaminated environment, but the relative contribution of each remains unclear. To examine how a contamination gradient affects patterns of metal(loid)s among periphyton, BPOM (benthic particulate organic matter), water, and sediment, we collected samples from multiple sites across a 210km stretch of the mine-contaminated Upper Clark Fork River, Montana. To investigate metal(loid) accumulation patterns among basal resources and aquatic insects, we collected samples of periphyton, BPOM, and larval insects from discrete habitat types at a single …

Catch My Drift? Perceptions And Experiences Of Pesticide Contamination Of Organic Crops In Montana, Sarah Rodgers

Graduate Student Theses, Dissertations, & Professional Papers

Pesticide drift and inadvertent contamination pose particular risks to organic production. Some organic producers have lost their crops, certification, and/or organic markets because of contamination events. Through this thesis research, I explain the perceptions and experiences that certified organic farmers in Montana have about drift and inadvertent pesticide contamination. I conducted semi-structured interviews with eleven certified organic farmers from various regions of Montana. Along with one-on-one interviews with organic farmers, interviews with industry and regulatory officials were conducted to better understand the policies and procedures that control what happens when drift occurs at the state level. Industry and regulatory official …

Lidar-Landsat Covariance For Predicting Canopy Fuels, Margaret D. Epstein

Graduate Student Theses, Dissertations, & Professional Papers

Managing wildfires in the western United States is becoming increasingly complex. Visualizing and quantifying canopy structures allows fire managers to both plan for fire and track recovery. Light detecting and ranging, or LiDAR can measure forests in three dimensions, but has limited spatial and temporal coverage. LiDAR-Landsat covariance uses machine learning to fill in the spatial and temporal gaps of LiDAR coverage with supplemental Landsat imagery. However, in order to capture real forest dynamics, a model needs to be stable enough to detect long term trends, sensitive to episodic disturbance, and general enough to work on multiple landcovers. The purpose …

Combined Effects Of Temperature And Heavy Metals On The Performance Of The Giant Salmonfly., James Frakes, Amanda Andreas, Benjamin P. Colman, Aurthur Woods

Graduate Student Theses, Dissertations, & Professional Papers

In many freshwater ecosystems, communities of aquatic insects are facing the combined stresses of warmer waters due to climate change and increased exposure to heavy metal toxicants. Although each stressor may threaten aquatic insects independently, they also likely interact in important ways to affect insect physiology and performance. Here we investigate this potential interaction using two populations of aquatic nymphs of the giant salmonfly, Pteronarcys californica, collected from adjacent rivers in Montana: naïve individuals from Rock Creek, a relatively pristine stream, and individuals from the Upper Clark Fork River, which has a history of heavy metal pollution and higher …

Lasso: Listing All Subset Sums Obediently For Evaluating Unbounded Subset Sums, Christopher N. Burgoyne, Travis J. Wheeler

Graduate Student Theses, Dissertations, & Professional Papers

In this study we present a novel algorithm, LASSO, for solving the unbounded and bounded subset sum problem. The LASSO algorithm was designed to solve the unbounded SSP quickly and to return all subsets summing to a target sum. As speed was the highest priority, we benchmarked the run time performance of LASSO against implementations of some common approaches to the bounded SSP, as well as the only comparable implementation for solving the unbounded SSP that we could find. In solving the bounded SSP, our algorithm had a significantly faster run time than the competing algorithms when the target sum …

A Machine Learning Algorithm Improves Surface Freeze-Thaw Classification, Fredrick Bunt

Graduate Student Theses, Dissertations, & Professional Papers

The frozen or thawed state of the land surface is an important factor affecting a wide range of natural processes such as surface water movement, the carbon cycle, and ecosystem development. It is also important for human endeavors such as permafrost engineering and agricultural planning. This makes having an accurate record important. The Freeze-Thaw (FT) Earth System Data Record (FT-ESDR) is a global, daily product that strives to be a reliable record of the FT ground state. In its current form, the FT-ESDR uses annual regression analysis of reanalysis surface air temperatures (SAT) and brightness temperatures (Tb) at each grid …

Re-Modeling The Interior: Spatial Methods And Policy Revisions To Improve Inventory And Designation Of Blm’S Areas Of Critical Environmental Concern, Amy H. Katz

Graduate Student Theses, Dissertations, & Professional Papers

The Bureau of Land Management (BLM) manages a vast amount of public land in the western United States, most of which they currently manage for multiple uses. Specific conservation and management of these lands could mitigate climate change impacts and contribute to the global initiative to conserve 30 percent of lands and waters by 2030. Particularly, the agency can achieve this through more effective administration of Areas of Critical Environmental Concern (ACEC), a designation that is prioritized under the Federal Land Policy and Management Act (FLPMA). To do so requires updated regulations that set clear parameters around inventory and designation, …

Development Of Nanodisc Affinity Capillary Electrophoresis To Study The Interaction Of Giα Protein With Cell Membranes, Bethany R. Emeigh

Graduate Student Theses, Dissertations, & Professional Papers

Guanine nucleotide-binding proteins, or G-proteins, are crucial to cell signaling by acting as molecular switches through interactions with membrane-bound receptors. G-proteins have become of greater interest due to the possibility of novel drug targets. The G-protein alpha subunit, Gα, binds GTP before localizing to the membrane to interact with other G-protein subunits and G-protein-coupled receptors (GPCRs). Gi lacks a hydrophobic region to promote localization to the membrane, but a co-translational lipidation of the N-terminal residue stabilizes this interaction.

Protein interactions with biological membranes are challenging to study due to the complex structure of membranes and the often-limited quantities of the …

Trading Financial Instruments Like A Video Game: Searching For Profit Using Deep Reinforcement Learning., Sebastian Coombs

Graduate Student Theses, Dissertations, & Professional Papers

Buying and selling Stocks, Foreign Currencies (FOREX), Commodities, and Cryptocurrencies have been a source of wealth generation, and more often, wealth loss for many brave enough to enter the financial markets. In this paper, the author builds on the work of Williams, J. 2022 and develops an agent-based method to solve this wealth generation problem with the use of neural networks. The author points out some assumptions made by Williams, J. 2022 that were sound in theory, but made the implementation of the algorithm presented in their paper diverge from the theory. The author proposes a fundamentally different algorithmic method, …

Development Of Regional Landslide Susceptibility Models: A First Step Towards Model Transferability, Gina M. Belair

Graduate Student Theses, Dissertations, & Professional Papers

Landslides are a globally pervasive problem with the potential to cause significant fatalities and economic losses. Although landslides are widespread, many at-risk regions may not have the high-quality data or resources used in most landslide susceptibility analyses. This study aims to develop regional susceptibility relationships that are versatile and use publicly available data and open-sourced software. Logistic Regression and Frequency Ratio susceptibility relationships were developed in 23 regions in Washington, Utah, North Carolina, and Kentucky, with a region referring to a unique area and data combination. Regions were diverse in their geology, morphology, climate, and nature and quality of their …