Physical Sciences and Mathematics Commons^™

Pond-Hindsight: Applying Hindsight Optimization To Partially-Observable Markov Decision Processes, Alan Olsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Partially-observable Markov decision processes (POMDPs) are especially good at modeling real-world problems because they allow for sensor and effector uncertainty. Unfortunately, such uncertainty makes solving a POMDP computationally challenging. Traditional approaches, which are based on value iteration, can be slow because they find optimal actions for every possible situation. With the help of the Fast Forward (FF) planner, FF- Replan and FF-Hindsight have shown success in quickly solving fully-observable Markov decision processes (MDPs) by solving classical planning translations of the problem. This thesis extends the concept of problem determination to POMDPs by sampling action observations (similar to how FF-Replan samples …

Sedimentological Controls On Fracture Distribution And The Network Development Within Meseverde Group Lithofacies, Uinta Basin, Utah, Ryan Christopher Sonntag

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Mesaverde Group, within the Uinta Basin, Utah, is a source of current significant production and contains several trillion cubic feet of undiscovered natural gas resources. Due to the low permeability of the matrix rock, understanding the geometry and properties of natural fractures is critical to the development of effective ways of finding and producing natural gas. In order to evaluate and model the potential connectivity of hydraulically induced fractures to natural fractures at depth, we examine the nature of the natural fracture network using scanline sampling, imagery analyses, core analyses, and microstructural analyses. Regional fracture sets identified include: N-S …

Ligand And Metal Effects On The Co-Release Reactivity Of Metal Acireductone And Flavonolate Complexes, Katarzyna Grubel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The research reported herein involves synthetic metal complexes of relevance to dioxygenase enzymes (Ni(II)-containing acireductone dioxygenase (Ni(II)-ARD) and quercentinase (2,4-flavonol dioxygenase) that promote oxidative carbon-carbon bond cleavage and CO release. The experiments focus on the elucidation of structure-reactivity relationships and evaluation of the conditions under which CO is generated.

It had been proposed that hydrogen bond donors in the secondary environment of the active site metal center in Ni(II)-ARD influence the coordination of the acireductone substrate on the nickel center. To evaluate this proposal, we investigated the Ni(II) coordination chemistry of an acireductone-type enolate anion using a supporting chelate ligand …

Factors Affecting Greater Sage-Grouse (Centrocercus Urophasianus) Survival And Movement In South-Central Utah, Danny Caudill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Greater sage-grouse are the largest North American grouse species and are dependent on sagebrush for survival. Sage-grouse populations have declined throughout the west. Habitat fragmentation and degradation are likely the main causes of declining populations, and concern has lead to the petitioning for the sage-grouse to be listed under the Endangered Species Act. Survival of adult and juvenile sage-grouse is thought to be limiting population growth. However, survival of juvenile sage-grouse is poorly understood. I aimed to improve the knowledge gap regarding juvenile sage-grouse survival. With improved knowledge of juvenile survival, management actions can be employed to benefit sage-grouse populations. …

From Hillslopes To Canyons, Studies Of Erosion At Differing Time And Spatial Scales Within The Colorado River Drainage, Christopher Tressler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis includes two different studies in an attempt to investigate and better understand the key characteristics of landscape evolution. In the first study, the rate of surface particle creep was investigated through the use of Terrestrial lidar at an archaeological site in Grand Canyon National Park. The second study developed ways to quantify metrics of the Colorado River drainage and reports the role of bedrock strength in the irregular profile of the trunk Colorado River drainage.

Archaeological sites along the Colorado River corridor in Grand Canyon National Park are eroding due to a variety of surficial processes. The nature …

Invertebrate Community Changes Along Coqui Invasion Fronts In Hawaii, Ryan T. Choi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Puerto Rican coqui frog, Eleutherodactylus coqui, was introduced to Hawaii in the late 1980s via the commercial horticulture trade. Previous research has shown that coquis can change invertebrate communities, but these studies were conducted at small scales using controlled, manipulative experiments. The objective of this research was to determine whether coqui invasions change invertebrate communities at the landscape scale across the island of Hawaii. At each invasion front, we measured environmental variability on either side of the front and removed sites that were too variable across the front to ensure that the impacts we measured were the result …

Understanding Teacher Users Of A Digital Library Service: A Clustering Approach, Beijie Xu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research examined teachers' online behaviors while using a digital library service—the Instructional Architect (IA)—through three consecutive studies. In the first two studies, a statistical model called latent class analysis (LCA) was applied to cluster different groups of IA teachers according to their diverse online behaviors. The third study further examined relationships between teachers' demographic characteristics and their usage patterns. Several user clusters emerged from the LCA results of Study I. These clusters were named isolated islanders, lukewarm teachers, goal-oriented brokers, window shoppers, key brokers, beneficiaries, classroom practitioners, and dedicated sticky users. …

Dynamics Of Equatorial Spread F Using Ground-Based Optical And Radar Measurements, Narayan P. Chapagain

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Earth's equatorial ionosphere most often shows the occurrence of large plasma density and velocity fluctuations with a broad range of scale sizes and amplitudes. These night time ionospheric irregularities in the F-region are commonly referred to as equatorial spread F (ESF) or plasma bubbles (EPBs). This dissertation focuses on analysis of ground-based optical and radar measurements to investigate the development and dynamics of ESF, which can significantly disrupt radio communication and GPS navigation systems. OI (630.0 nm) airglow image data were obtained by the Utah State University all-sky CCD camera, primarily during the equinox period, from three different longitudinal …

A Fully Automatic Segmentation Method For Breast Ultrasound Images, Juan Shan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Breast cancer is the second leading cause of death of women worldwide. Accurate lesion boundary detection is important for breast cancer diagnosis. Since many crucial features for discriminating benign and malignant lesions are based on the contour, shape, and texture of the lesion, an accurate segmentation method is essential for a successful diagnosis. Ultrasound is an effective screening tool and primarily useful for differentiating benign and malignant lesions. However, due to inherent speckle noise and low contrast of breast ultrasound imaging, automatic lesion segmentation is still a challenging task.

This research focuses on developing a novel, effective, and fully automatic …

Individualistic Response Of Piñon And Juniper Tree Species Distributions To Climate Change In North America's Arid Interior West, Jacob R. Gibson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Piñon and juniper tree species have species-specific climatic requirements, resulting in unique distributions and differential responses to climate change. Piñons and junipers co-dominate the arid woodlands of North America as groups with widespread hybridization. Two piñons, Pinus edulis; P. monophylla, and four junipers, Juniperus deppeana var. deppeana; J. monosperma; J. occidentalis; J. osteosperma, are endemic to the midlatitude interior west and form three groups of hybridizing sister species, P. edulis-P. monophylla; J. deppeana var. deppeana-J. monosperma; J. occidentalis-J. osteosperma. Recent droughts have caused widespread mortality among piñons, but have had less impact on …

Timing Of Seasonal Migration In Mule Deer: Effects Of Climate, Plant Phenology, Andlife-History Characteristics, Kevin L. Monteith, Vernon C. Bleich, Thomas R. Stephenson, Becky M. Pierce, Mary M. Conner, Robert W. Klaver, R. Terry Bowyer

Wildland Resources Faculty Publications

Phenological events of plants and animals are sensitive to climatic processes. Migration is a life-history event exhibited by most large herbivores living in seasonal environments, and is thought to occur in response to dynamics of forage and weather. Decisions regarding when to migrate, however, may be affected by differences in life-history characteristics of individuals. Long-term and intensive study of a population of mule deer (Odocoileus hemionus) in the Sierra Nevada, California, USA, allowed us to document patterns of migration during 11 years that encompassed a wide array of environmental conditions. We used two new techniques to properly account for interval-censored …

Surface Geometry And Heat Flux Effect On Thin Wire Nucleate Pool Boiling Of Subcooled Water In Microgravity, Troy Munro, Heng Ban, Jr Dennison

Presentations

No abstract provided.

Surface Geometry And Heat Flux Effect On Thin Wire Nucleate Pool Boiling Of Subcooled Water In Mictrogravity, Troy Munro, Heng Ban

Presentations

No abstract provided.

Building An Interdisciplinary Research Program In Water Conservation: Approach, Preliminary Findings, And Next Steps, David E. Rosenberg, Joanna Endter-Wada, Arthur Caplan, Diana T. Glenn

Diana T. Glenn

Effective urban water conservation programs must harness a synergy of new technologies, public policies, social cost pricing, information dissemination, citizen engagement, and coordinated actions across decision making scales. Together, these factors affect the volume of water an individual user ultimately saves and the overall success of a conservation program or programs. Over the past 18 months, we have started building an interdisciplinary research program in urban water conservation to quantify and assess the effects of these interconnected factors to motivate citizen engagement. We have interviewed water utility managers and conservation coordinators across the state of Utah, held focus groups with …

Collaborative Strategic Board Games As A Site For Distributed Computational Thinking, Matthew Berland, Victor R. Lee

Instructional Technology and Learning Sciences Faculty Publications

This paper examines the idea that contemporary strategic board games represent an informal, interactional context in which complex computational thinking takes place. When games are collaborative – that is, a game requires that players work in joint pursuit of a shared goal – the computational thinking is easily observed as distributed across several participants. This raises the possibility that a focus on such board games are profitable for those who wish to understand computational thinking and learning in situ. This paper introduces a coding scheme, applies it to the recorded discourse of three groups of game players, and provides qualitative …

Electron Induced Luminescence Of Insulating Polymeric Materials, Doug Ball

Senior Theses and Projects

The study of luminescence and electron transport in disordered insulating materials provides detailed information about the material structure and interaction of incident electrons within a material. Electron induced luminescence of insulating polymeric materials has been observed in tests by the USU Materials Physics group. Conduction electrons can transition between extended states in the valence and conduction band and a distribution of localized trapped states within the band gap. Electron transport and luminescence is governed by the distribution of states and transition rates between them. This study investigates the exponentially decaying signatures of both luminescence and sample current of M55J under …

A Time-Of-Flight Mass Spectrometer For Upper Atmospheric Measurements, Addison E. Everett, E. A. Syrstad

Graduate Student Posters

The mesosphere-lower thermosphere (MLT) is perhaps the least understood region of the earth’s atmosphere due to the difficulty of obtaining in-situ measurements. Access to the MLT is limited to high-speed sounding rockets for brief periods of at most a few minutes. Because of its wide mass range and high scan rate, Time-of-flight mass spectrometry (TOF-MS) has potential to resolve thin layers of diverse species in the MLT. However, because ambient pressures can reach into the millitorr range, TOF-MS has rarely been applied in the MLT due to its dependence on high voltages and microchannel plate (MCP) detectors. A novel dual …

Early Observations Of The Middle Atmosphere Above Usu With The World’S Most Sensitive Lidar, Lance W. Petersen, Marcus J. Bingham, Vincent B. Wickwar, Joshua P. Herron

Posters

Extensive measurements have been made of the upper atmosphere by satellites and the lower atmosphere is measured twice daily by weather balloons. In contrast, the middle atmosphere is a difficult area to measure and therefore has been much less extensively studied. We are currently upgrading an old lidar system to a new system that will be 70 times more sensitive, making this the most sensitive lidar of its kind in the world. The upgrade consists of combining the outputs of 18 and 24 watt Nd:YAG lasers; implementing an optical chain to detect backscattered light using an existing large, four-mirror telescope; …

Quantum Gravity In Relativistic Phase Space, Jeffrey Hazboun

Presentations

No abstract provided.

Effects Of Micro-Gravity On Thin-Wire Subcooled Nucleate Boiling Dynamics, Troy Munro, Andrew Fassmann

Posters

Nucleate boiling is a highly effective means of transferring heat, and as space exploration begins to reach farther from Earth, efficient heat management systems in microgravity are becoming increasingly important. In the summer of 2010, members of the USU Get Away Special (GAS) team flew aboard NASA’s Weightless Wonder in order to study the effect of various system parameters on nucleate boiling heat transfer behavior in microgravity. This one dimensional study of boiling used a new geometry never tried before and concluded that heat transfer rates during boiling in microgravity do not significantly differ from those observed on Earth. These …

Development Of Optimal Bubble-Seeding Microheaters To Study Nucleate Boiling Heat Transfer In Microgravity, Ryan Martineau, Iggy Matheson, Landon Hillyard

Posters

Heat management is a critical issue facing engineers of spaceflight systems. Nucleate boiling has high heat transfer rates, but further study is needed to apply this method effectively to a heat transfer system in a microgravity environment. The USU Get Away Special (GAS) team is conducting a series of experiments aboard NASA's "Weightless Wonder" aircraft to further understanding of nucleate boiling activity in microgravity. Two specific focuses of the current experiment are determining optimal surface geometries of microheater arrays designed to induce nucleate boiling and constructing a lighting and video system to spatially and temporally resolve the anticipated jets of …

Telescopes, Robots And Computers: Using Technology To See The Cosmos, Shane L. Larson

Public Talks

No abstract provided.

Boil, Boil, Toil, And Trouble - Connecting With The Community Through Microgravity Boiling Experiments, Troy Munro, Andrew Fassmann, Heng Ban, John R. Dennison

All Physics Faculty Publications

No abstract provided.

Surface Geometry And Heat Flux Effect On Thin Wire Nucleate Pool Boiling Of Subcooled Water In Microgravity, Troy Munro, Andrew Fassman, Heng Ban, Jr Dennision

Conference Proceedings

In the summer of 2010, undergraduates from the USU Get Away Special team flew a nucleate pool boiling experiment on NASA’s Weightless Wonder to study nucleate boiling heat transfer in microgravity. The motivation of this research was to understand the effects of surface geometry and heat flux applied to a thin wire heater for the design and development of efficient thermal management systems for space applications. The specific objectives were to observe and characterize behaviors of boiling onset, steady state heat transfer, and bubble dynamics with respect to nucleate boiling of subcooled water.. Using three thin platinum wire geometries and …

Surface Geometry And Heat Flux Effect On Thin Wire Nucleate Pool Boiling Of Subcooled Water In Microgravity, Troy Munro, Andrew Fassman

Presentations

The motivation of this nucleate boiling research is to understand the effects of surface geometry and heat flux as applied to a thin wire heater. This will further the understanding of the fundamental behaviors of boiling onset, steady state heat transfer, and bubble dynamics with respect to nucleate boiling with the goal of creating efficient thermal management systems for future space applications. Using three different thin platinum wire geometries and five different power levels, subcooled water was boiled over a period of approximately 30 seconds for 15 parabolic arcs to simulate microgravity. To represent the trends in bubbles behavior across …

Einstein's Life: Advanced Science And Life In The Modern Age, Shane L. Larson

Public Talks

No abstract provided.

In Situ Checks Of Sonic Anemometer Temperature Calibration, David Cook, Michael Negale

Physics Student Research

The temperature calibration of the Gill Instruments WindMaster Pro sonic anemometer used in the ARM SGP ECOR systems is actually a curve, but is approximated with a linear fit for field use. The original calibrations were performed in a temperature-controlled chamber. The linear fit slope is only applied to the calculation of sensible heat flux and not to the reported temperature. The linear fit results in an underestimate of sensible heat flux during cold ambient temperatures and an overestimate during hot ambient temperatures. In situ calibrations performed using five years of ARM SGP data reveal how poorly the temperature is …

The Design And Construction Of A Microgravity Boiling Experiment, Troy Munro

Presentations

No abstract provided.

Effects Of Heat Flux On Nucleate Boiling In Microgravity, Andrew Fassman

Presentations

No abstract provided.

Lettau Affect Colloquium: Or Seeing Natural Philosophy With Len, Leonard F. Hall

All Physics Faculty Publications

No abstract provided.