Physical Sciences and Mathematics Commons^™

Characterizing Silicate Materials Via Raman Spectroscopy And Machine Learning: Implications For Novel Approaches To Studying Melt Dynamics, Blake O. Ladouceur

Doctoral Dissertations

Silicate melt characteristics impose dramatic influence over igneous processes that operate, or have operated on, differentiated bodies: such as the Earth and Mars. Current understanding of these melt properties, such as composition, primarily comes from investigations on their volcanic byproducts. Therefore, it is imperative to innovate on modalities capable of constraining melt information in environments where a reliance on laboratory methods is severed. Recent investigations have turned to Raman Spectroscopy and amorphous volcanics as a suitable pairing for exploring these ideas. Silicate glasses are a proxy for igneous melts; and Raman spectroscopy is a robust analytical technique capable of operating …

Acoustic Directivity: Advances In Acoustic Center Localization, Measurement Optimization, Directional Modeling, And Sound Power Spectral Estimation, Samuel David Bellows

Theses and Dissertations

Sound radiation from an acoustic source typically exhibits directional behavior, as is the case for the human voice, musical instruments, and loudspeakers, to name just a few. The necessity of directional data for many applications, such as sound source modeling, microphone placement, room acoustical design, and auralization, motivates directivity measurements. However, these measurements require careful understanding and implementation to produce the most meaningful results. Accordingly, this dissertation addresses several topics relevant to directivity theory, measurement, processing, and application. It first expands and amends previously published concepts of an acoustic source center and demonstrates the close relationship between the center and …

Identifying Advantages To Teaching Linear Regression In A Modeling And Simulation Introductory Statistics Curriculum, Kit Harris Clement

Dissertations and Theses

Statistical association is a key facet of statistical literacy: claims based on relationships between variables or ideas rooted in data are found everywhere in media and discourse. A key development in introductory statistics curricula is the use of simulation-based inference, which has shown positive outcomes for students, especially in regards to statistical literacy and conceptual understanding. In this dissertation project, I investigate students from the Change Agents for the Teaching and Learning of STatistics (CATALST) curriculum in activities I designed for learning statistical association and linear regression. First, I analyzed the informal line fitting strategies of CATALST students. Findings suggest …

Determining The Refractive Index Of Phytoplankton Via Direct Measurement Of Cellular Structures, Michael Kamowski

Master's Theses

The refractive index of phytoplankton has never been directly measured before despite its importance towards studying the optical characteristics of marine particles. Previous attempts to measure it have been done through indirect methods. While these methods have proven useful, they contain assumptions about the particles morphology and composition that cause for uncertainty with the measurements. Through the use of the 3D Cell Explorer, a high precision holotomographic microscope, the RI of phytoplankton can be directly measured for the first time. With volume measurements, the phytoplankton were found to not display a single bulk RI, instead the bulk RI was different …

Atmospheric Impacts From The 2010 Deepwater Horizon Oil Spill, Charles Philip Johnson

LSU Master's Theses

Although the ecological devastations induced by an oil spill are well studied, the hydrometeorological impacts from a long-term slick have gone unnoticed. The ocean-surface alterations stemming from the lasting oil footprint increase solar radiation absorption which in turn alters the surface pressure and moisture gradients and wind speeds thereby influencing precipitation surrounding the oil spill. Revealing the potential impacts from these could better aid in the safety of crews cleaning spills and provide a better understanding of how humans alter the landscape. This thesis examines the changes in local hydrometeorology brought on by the 2010 summer Deepwater Horizon (DWH) oil …

Modeling The Impacts Of Sea Level Rise In Coastal Virginia At Multiple Scales, George Murray Mcleod Iv

OES Theses and Dissertations

Relative sea level is increasing along the Mid-Atlantic coast of the United States and the rate of relative sea level rise (ΔRSL) for Coastal Virginia is approximately double the rate of global sea level rise (ΔSLRG)(1). The potential impacts posed to communities by ΔRSL are best understood by examining the spatial relationship between the upper limits of ocean-connected waters and the geographic positioning of critical natural and societal assets. This research examines this problem at three spatial scales to quantify the impacts of ΔRSL and storm flooding events on (i) structural and transportation infrastructure for the tide-influenced coastal zone of …

Studies Of The Ionosphere-Thermosphere Responses To Multi-Scale Energy Deposition Processes, Haonan Wu

All Dissertations

The Ionosphere-Thermosphere (I-T) system is greatly affected by the magnetospheric energy deposition from above and subjected to forcing from the lower atmosphere simultaneously. A central problem in studying the coupled I-T system is to analyze the multi-scale processes naturally embedded in both ways. Magnetospheric energy input such as auroral precipitation and electric field demonstrates multi-scale structures during magnetic storms, resulting in multi-scale I-T responses when deposited into the I-T system. To better quantify the multi-scale aurora and electric field, we developed a new data assimilation model based on a multi-resolution Gaussian process model to synthesize empirical models and observational data …

Modeling, Simulation And Control Of Microrobots For The Microfactory., Zhong Yang

Electronic Theses and Dissertations

Future assembly technologies will involve higher levels of automation in order to satisfy increased microscale or nanoscale precision requirements. Traditionally, assembly using a top-down robotic approach has been well-studied and applied to the microelectronics and MEMS industries, but less so in nanotechnology. With the boom of nanotechnology since the 1990s, newly designed products with new materials, coatings, and nanoparticles are gradually entering everyone’s lives, while the industry has grown into a billion-dollar volume worldwide. Traditionally, nanotechnology products are assembled using bottom-up methods, such as self-assembly, rather than top-down robotic assembly. This is due to considerations of volume handling of large …

Addressing Soil Carbon Sequestration Response From Multispecies Dairy Forage Systems And Modeling Rangeland Beef Cow Dry Matter Intake Using Precision Enteric Emissions Measurements, Lillian J. Mcfadden

Electronic Theses and Dissertations

Regenerative agriculture is a pressing matter for the dairy industry to address cropland sustainability and carbon sequestration. One regenerative management practice that has been identified to help with row crop sustainability for key metrics like soil organic carbon (SOC) is complex covers. When producers use complex covers one of the main challenges is that it takes time to detect a change in SOC. However, simulation models are a tool that can be used to help determine if a regenerative practice is a strategy that gives the best results (i.e., increased SOC) while aligning with long-term production goals. Therefore, our objectives …

Understanding The Impacts Of Freshwater Fluxes On The Biogeochemistry Of The Coastal Arctic: A Case Study Of Prudhoe Bay, Francesca Lingo

Dissertations and Theses

The Arctic region, undergoing significant environmental changes due to rapid warming, faces alterations in air temperatures, melting permafrost, declining sea ice, and changes in riverine inputs. These shifts have profound implications for Arctic coastal ecology and biogeochemical cycles. This study, focusing on Alaska's North Slope, explores the influence of freshwater fluxes on water optical properties, vital for accurate satellite remote sensing interpretations. Our approach combined field measurements, existing data, and satellite remote sensing retrievals to identify biogeochemical gradients and their seasonal and interannual variations. A novel finding was the unique CDOM composition in Prudhoe Bay, characterized by a lower molecular …

Modeling Vascular Diffusion Of Oxygen In Breast Cancer, Tina Giorgadze

Senior Projects Spring 2023

Oxygen is a vital nutrient necessary for tumor cells to survive and proliferate. Oxygen is diffused from our blood vessels into the tissue, where it is consumed by our cells. This process can be modeled by partial differential equations with sinks and sources. This project focuses on adding an oxygen diffusion module to an existing 3D agent-based model of breast cancer developed in Dr. Norton’s lab. The mathematical diffusion module added to an existing agent-based model (ABM) includes deriving the 1-dimensional and multi-dimensional diffusion equations, implementing 2D and 3D oxygen diffusion models into the ABM, and numerically evaluating those equations …

Modeling The Effects Of Projected Climate Warming On Stream Temperatures In The Stillaguamish River Basin, Emily E. Smoot

WWU Graduate School Collection

The Stillaguamish River is a snow-and-rain mixed basin and the fifth largest river in the Puget Sound basin. Elevations in the 1700 km² Stillaguamish River basin reach roughly 2000 m and historically a snowpack is sustained above 1000 m. Snowmelt in the basin is important for sustaining spring and summer streamflow and buffering stream temperatures. Stream temperature increases are of significant concern because of the threatened Chinook salmon (Oncorhynchus tshawytscha) population.

I reexamined projected stream temperatures in the Stillaguamish River by forcing the coupled Distributed Hydrology Soil Vegetation Model and River Basin Model with dynamically downscaled meteorological …

Direct Parameter Fitting Of Action Potentials In Skeletal Muscle Cells Which Include Longitudinal Segments, Tyme Suda

Browse all Theses and Dissertations

Excitation of skeletal muscle cells triggers a large voltage spike known as an action potential (AP), leading to muscle contraction. Modeling of an AP is typically done using the method developed by scientists Hodgkin and Huxley (HH). In the HH method, voltage and time gated Na+ and K+ ionic currents are simulated, along with a positive “Leak” ionic current and capacitive current. Due to the complexity and the computational time required for simulation, direct fitting of HH parameters to experimental APs has rarely been attempted. A previous thesis at Wright State performed direct fitting for the case of a single …

Modeling Current And Future Saltmarsh Distribution In Arcata Marsh, Madeline Kay Mcnerthney

Cal Poly Humboldt theses and projects

Saltmarsh habitat is vulnerable to Sea Level Rise (SLR) and requires long-term management plans for communities to continue to benefit from their ecosystem services. This study analyzed the variation of above-ground vegetation biomass throughout I Street Marsh, using multiple variables, including classified vegetative community types, elevation and remote sensing indexes comprised of both visual (Red, Green, Blue) and non-visual (Red Edge, Near Infrared) bands. Plant community types were classified using a cluster analysis, and distinguished three communities, based on dominant species: Salicornia, Spartina, and a mixed type (diverse floristic makeup, with no dominant species). Above-ground biomass was significantly higher in …

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 …