Physical Sciences and Mathematics Commons^™

A Tale Of Two Working Landscapes, Sage C. Sutcliffe

Graduate Student Theses, Dissertations, & Professional Papers

No abstract provided.

Influence Of Cross-Country Skiing & Off-Leash Dogs On Wildlife Habitat Use In Lubrecht Experimental Forest, Sophie Ann Morris

Graduate Student Theses, Dissertations, & Professional Papers

Outdoor recreation activities are seen as a type of anthropogenic stressor that can significantly impact wildlife. Despite winter recreational activities having a more negative effect on wildlife compared to summer or aquatic recreation, they are the least studied in terms of impact (Larson et al., 2016). Wildlife species can be influenced both temporally and spatially by the development of winter recreation trails and snow-based recreation (Braunisch et al., 2011; Olsen et al., 2018). This research combines natural and social science methods to assess how cross-country skiers affect wildlife activity patterns, guiding decisions about managing recreation. During two winter data collections, …

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 …

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 …

Paragenesis Of The Austin Chalk Formation In Southwest Texas, Mitchell C. Sherry

Graduate Student Theses, Dissertations, & Professional Papers

Presented in this study is a detailed investigation of the paragenesis and diagenetic processes of the Austin Chalk Formation in southwest Texas, utilizing a combination of core-based, petrographic, mineralogic, SEM, and geochemical based analyses. This study is conducted on a single whole rock core from an oil and gas producing well in Webb County, Texas. At this distal shelf location within the Maverick Basin, the Austin Chalk Formation consists of foraminiferal wackestones, siliceous wackestones, foraminiferal mudstones, bentonites, and foraminiferal packstone facies. These facies were deposited below wave base through pelagic, hemipelagic, and gravity driven processes. Petrographic and SEM analyses reveal …

Diagenesis And Quartz Grain Provenance Of The Turner Sandstone, Carson Lee Broaddus

Graduate Student Theses, Dissertations, & Professional Papers

Provenance analysis of sedimentary rocks is an essential tool for basin analysis and paleogeographic reconstructions. Numerous tools and analytical methods have been developed over the years to investigate the source of detrital constituents in sedimentary rocks. The Late Cretaceous (Turonian) Turner Sandstone in the eastern Powder River Basin (PRB), WY, and the time equivalent Frontier Formation in the western PRB are commonly described as the remnants of a marginal marine depositional system. However, contradictory evidence exists about the source of those deposits. Here, I present results from a comprehensive scanning electron microscope panchromatic cathodoluminescence (SEM-PCL) analysis of >1200 individual sand-sized …

A Soil-Plant-Atmosphere Continuum Model To Simulate Seedling Response To Water Stress, Michael Kurt Kendree Jr.

Graduate Student Theses, Dissertations, & Professional Papers

Most current ecohydrologic models simplify the hydraulics that are at play in plant-water relationships by assuming that the water content within the plant is static. In reality, plants have a relative water content that varies with time in response to environmental stresses. To some extent, variations in plant relative water content are regulated by changes in the osmotic potential of water within plant cells, which contributes to the resilience of plants during periods of water shortage. We present a model that simulates plant water transport and storage within the soil-plant-atmosphere continuum. The model incorporates the role of osmotic regulation in …

Better Understanding The Barred Owl, Adam Lee Potts

Graduate Student Theses, Dissertations, & Professional Papers

This thesis research presents an analysis of barred owl nest site selection in an understudied region of their expanded range. The barred owl has dramatically expanded its range westwards over the last 150 years, prompting multiple conflicting reinterpretations of their species account. Hypotheses of range expansion are reviewed to provide context for this study’s research. This study gathers empirical data on nest site selection in the mixed conifer forests of Montana’s Seeley-Swan and Mission Valleys. Eight barred owl nests were located following extensive territory surveys. Field measurements of tree height and diameter using USFS Forest Inventory and Analysis (FIA) plot …

A Social-Ecological Approach To Evaluating Short-Term Water Leasing For Streamflow Conservation In Montana, Usa, Logan A. Brauer

Graduate Student Theses, Dissertations, & Professional Papers

Streams throughout Montana are increasingly caught between increasing temperatures, decreasing summer precipitation, and heavy water demand for irrigated agriculture. Amid rapidly growing urban populations and uncertain climatic futures, many watersheds in Montana may face water shortages that impact aquatic species and habitat in the upcoming years. Conservation efforts around the state are working to mitigate water stress in these streams especially during the late summer season, when streamflow is naturally lower, and/or in times of drought. One policy solution to address low flows is a concept known as temporary leasing or split season leasing programs (SSLP), whereby an entity (e.g., …

Identifying And Predicting Patterns Of Snowpack Ripening With Machine Learning Methods, Clement Cherblanc

Graduate Student Theses, Dissertations, & Professional Papers

The timing of water release from the snowpack plays key roles in ecosystem services, groundwater recharge, and water resource management. However, two internal barriers in a standing snowpack must be overcome before runoff can outflow from the base: 1) the cold content must be exhausted, and 2) the interconnected network of snow grains must be filled with liquid water to residual saturation. Expressing the liquid water as latent heat allows the two barriers to be grouped as an energy (J/m²) to define a snowpack’s Runoff Energy Hurdle (REH). The growth and loss of REH is driven by evolution of pore …

Analysis Of The Transformations Of Laguna Melincué Wetland, Argentina, Bianca Giunti

Graduate Student Theses, Dissertations, & Professional Papers

In Argentina, freshwater wetlands are threatened by land use changes, unsustainable irrigation practices, and climate change. Twenty-three wetlands cover 5,176,578 ha of the Argentinian territory and have been designated as wetlands of international importance by the Convention of Wetlands (Kandus et al., 2008; Ramsar Sites Information Service, 2022). These figures are significant given Argentina’s unique geographic location on a central migratory bird flyway and the profound biological diversity found in these wetlands (Jahn et al., 2013; Red Aves Internacionales, 2015). The Government of Argentina has recently moved to implement wetland protection and conservation policies. Nevertheless, policy and governance efforts to …

Snow Spheres And Ice Cubes, John Adam

Mathematics & Statistics Faculty Publications

This article, titled "Snow spheres and ice cubes," discusses the melting of snowballs and ice cubes. It explains that in standard calculus textbooks, it is shown that a snowball melting at a rate proportional to its surface area will have its radius decrease at a constant rate, assuming it remains spherical as it melts. The article then poses several questions related to this concept, including the proportion of a smaller snow sphere that remains when half of a larger one has melted, the value of p for which the smaller sphere first melts, and the volume reduction factor for cubes …

The Geometry Of Dynamic Time-Dependent Best-Worst Choice Pairs, Sasanka Adikari, Norou Diawara, Haim Bar

Mathematics & Statistics Faculty Publications

There has been increasing interest in best–worst discrete choice experiments (BWDCEs) in health economics, transportation research, and other fields over the last few years. BWDCEs have distinct advantages compared to other measurement approaches in discrete choice experiments (DCEs). A systematic study of best–worst (BW) choice pairs can be traced back to the 1990s. Recently, new ideas have been introduced to the subject. Calculating utility helps measure the attractiveness of BW choices. The goal of this paper is twofold. First, we extend the idea of the BW choice pair to include dynamic, time-dependent transition probability and capture utility at each time …

Preface, Mohamed Mahdi Tekitek, Manfred Krafczyk, Li-Shi Luo

Mathematics & Statistics Faculty Publications

[Introduction] Matter, conceptually classified into fluids and solids, can be completely described by the microscopic physics of its constituent atoms or molecules. However, for most engineering applications, a macroscopic or continuum description has usually been sufficient due to the large disparity between the spatial and temporal scales relevant to these applications and the scales of the underlying molecular dynamics. In this case, the microscopic physics merely determines material properties such as the viscosity of a fluid or the elastic constants of a solid. These material properties cannot be derived within the macroscopic framework, but the qualitative nature of the macroscopic …

Fire Severity Mediates Marten And Fisher Occurrence: Impacts Of The Dixie Fire On A Carnivore Community, Christopher James Collier

Cal Poly Humboldt theses and projects

The consumption of an astounding one million acres resulted from California’s largest single fire to date, the 2021 Dixie Fire. The social and economic losses associated with the fire were immediately apparent, but the effects on wildlife remained unknown. While previous research has suggested mixed or low severity fire may be beneficial to certain wildlife species, the responses to megafires are poorly understood for many carnivores. To better understand these responses to severe fire, I used a random sampling design stratified by burn severity to survey in and around the Dixie Fire footprint using baited camera stations. This allowed me …

Incorporating Equity Into Sea-Level Rise Planning: Perspectives From Practitioners Across California, Nayré Herrera

Cal Poly Humboldt theses and projects

Scholars along with national and state governments have increasingly made calls to incorporate an equity lens into climate adaptation processes and into sea-level rise planning specifically. However, the language used in these high-level policies remains vague. There remains a need to learn from practitioners on the ground about the challenges and opportunities for effectively incorporating an equity lens into sea-level rise adaptation and planning efforts. I conducted interviews with 17 individuals who are working within their agencies or organizations to advance equity across the California coast along with a review of 17 California coastal policy documents to gain insights into …

The "Upside-Down" River: Trends In Total Nitrogen, Total Phosphorus, And Microcystin Concentration In The Klamath Basin, 2010-2021, Kayla M. Fitzpatrick

Cal Poly Humboldt theses and projects

The Klamath River tends to experience impaired upstream water quality, which improves downstream. Although this consensus is accepted, an updated spatiotemporal analysis of certain water quality parameters has not been conducted since 2017. With four of the Klamath River’s dams slated for removal by the end of 2024, it is critical to have an updated assessment of current water quality conditions from which to compare conditions following dam removal. In this study, total nitrogen (TN), total phosphorus (TP), and microcystin data from 2010-2021 were analyzed to determine concentration trends from Link Dam to the Klamath River Estuary.

Concentrations of TN …

Ultradeep Atca Imaging Of 47 Tucanae Reveals A Central Compact Radio Source, Alessandro Paduano, Arash Bahramian, James C. A. Miller-Jones, Adela Kawka, Tim J. Galvin, Liliana E. Rivera Sandoval, Sebastian Kamann, Jay Strader, Laura Chomiuk, Craig O. Heinke

Physics & Astronomy Faculty Publications

We present the results of an ultradeep radio continuum survey, containing ∼480 hr of observations, of the Galactic globular cluster 47 Tucanae with the Australia Telescope Compact Array. This comprehensive coverage of the cluster allows us to reach rms noise levels of 1.19 μJy beam−1 at 5.5 GHz, 940 nJy beam−1 at 9 GHz, and 790 nJy beam−1 in a stacked 7.25 GHz image. This is the deepest radio image of a globular cluster and the deepest image ever made with the Australia Telescope Compact Array. We identify ATCA J002405.702-720452.361, a faint (6.3 ± 1.2 μJy at 5.5 …

Editorial: Artificial Intelligence, Machine Learning, And Data-Mining Techniques To Increase Cost-Effectiveness In Healthcare., P Wilner Jeanty, Marie-Rachelle Narcisse, Romain Crastes Dit Sourd

Ambulatory and Primary Care Articles

No abstract provided.

Optimizing Microbe-Infected Mosquito Release: A Stochastic Model For Malaria Prevention, Steeven Belvinos Affognon, Henri E.Z. Tonnang, Philip Ngare, Benard Kipchumba Kiplangat, Shirley Abelman, Jeremy K. Herren

All Peer-Reviewed Publications

Malaria remains a critical public health challenge in Africa, demanding innovative control strategies. This study introduces a novel approach using Microsporidia MB-infected mosquitoes and stochastic optimal control within a Lévy process framework to regulate mosquito release strategies. The primary goal is to optimize Microsporidia MB prevalence within mosquito populations to disrupt Plasmodium transmission to humans. By incorporating Lévy noise into the modeling process, we capture the inherent randomness of mosquito dynamics, improving intervention accuracy. The model, guided by the Hamilton–Jacobi–Bellman (HJB) equation, optimizes release protocols while accounting for key environmental factors like seasonality and temperature fluctuations. Results show that intervention …

Integration Of 3d Structural Modelling And Well Logging Analysis In The Evaluation Of October Oil Field, Gulf Of Suez, Egypt, Lamiaa Yahia, Mostafa Toni, Farouk I. Metwalli, M. H. Mansour, Amir Ismail

Trends in advanced sciences and technology

An extensive study of the NUBIA and MAT reservoirs, incorporating numerous data sources, enhances the accuracy of production forecasts for hydrocarbon exploration and development. This study aims to integrate seismic and well data for re-assessment and to delineate the geological and petrophysical characteristics of the October oil field which is one of the most productive in the central Gulf of Suez, but it has recently witnessed a drop in output in some regions, and some wells have begun to depletion. While facies modeling enabled the spatial distribution of lithologic facies inside the constructed 3D structural model, which reflected two types …

Modeling Earthquake Catalog (1985-2022) In Northern Egypt Using Space-Time Epidemic-Type Aftershock Sequences (Etas), Mariam Ramadan, Amir Ismail, Amin E. Khalil, Hesham Abdelhafiez, Nouran S. Salama

Trends in advanced sciences and technology

Earthquakes have the largest damaging effects among natural disasters on a global scale. Efforts for reducing their effects have taken place for a long time. The prediction of earthquakes was the main target, however the studies conducted were not successful. As a replacement, seismic hazard assessments were adopted to predict the levels of ground motion for the possible future large earthquakes. This approach is probabilistic in nature that rely on the quality of earthquake catalog. The probabilistic model adopted is built on the assumption that the events in the earthquake catalog are random Poisson distribution, assuming that events are independent …

Structural And Functional Studies Of The Human Members Of The Macrophage Migration Inhibitory Factor Family, Andrew Parkins

University of the Pacific Theses and Dissertations

Macrophage migration inhibitory factor (MIF) and D-dopachrome tautomerase (D-DT) are the two human members of the MIF superfamily, which are implicated in an array of autoimmune disorders, inflammatory diseases, and cancer via their pleiotropic functionality. Despite only sharing 34% sequence identity, MIF and D-DT have high structural homology and overlapping functional traits, including activation of the type II cell surface receptor CD74 and keto-enol tautomerase activity. The MIF and/or D-DT-induced activation of CD74 leads to signaling cascades pivotal for cell growth, proliferation, and inhibition of apoptosis. Such characteristics make MIF and D-DT attractive molecular targets for drug discovery.

Currently, all …

Fretting Corrosion Wear Of Titanium-Based Alloy (Ti-6al-4v) In 0.9 Wt.% Nacl Solution, Chen-En Lu, Wen-Ken Li, Hung-Hua Sheu, Jeou-Long Lee, Hung-Bin Lee

Journal of Marine Science and Technology–Taiwan

In this study, a high precision fretting tribo-corrosion tester used to analyze the wear and corrosion behavior of Ti alloys in a fretting motion condition. The tester, operated in a ball-on-plate mode, was employed in the fretting corrosion study of metallic bio-materials (Ti and Ti-6Al-4V) under different loads (0 and 10 N), electrolytes (0.9 wt% NaCl and SBF) and fixed displacement frequency (1 Hz). Using profilometer, optical microscope in the experimental analysis and three-body mechanism in the theoretical analysis, the fretting corrosion performances of these bio-medical metals, such as velocity accommodation characteristics, friction, wear, and scratch profile were examined in …

A New-Type Deep Learning Model Based On Shapley Regulation For Containerized Freight Index Prediction, Yen-Chang Shih, Ming-Shue Lin, Taih-Cherng Lirn, Jih-Gau Juang

Journal of Marine Science and Technology–Taiwan

In this study, we have crafted an innovative methodology that represents a groundbreaking synthesis of deep learning techniques with cooperative game theory. In this study, we use the accuracy of data prediction by different LSTM models as a measurement index and assign different LSTM models corresponding weights through the Shapley value calculation method to construct a more accurate predictive analysis model. We use this improved Shapley regulation model to calibrate a long short-term memory (LSTM) neural network by using historical freight data to predict the China Container Freight Index (CCFI), the leading export container freight index commonly used in China. …

Applicability Of Reducing Valve Timing Overlap For Diesel Engines Under High Exhaust Back Pressure, Chien-Cheng Chen, Yuan-Liang Jeng, Shun-Chang Yen

Journal of Marine Science and Technology–Taiwan

The exhaust back pressure of diesel engines becomes increasing higher nowadays. As an example, the De-NOx system and DE-SOx system necessitated by the increasingly stringent emission standards, would result in increased exhaust back pressure for those diesel engines adopting such systems. Some ships adopt underwater exhaust system to save space on the working deck and to reduce noise and air pollution, while the hydrostatic pressure under water level has made the exhaust back pressure of diesel engines getting much higher. Under high exhaust back pressure, to keep discharging exhaust unhindered and operating smoothly for diesel engine, it often results in …

Elimination Of Noise In A Ship Cabin Using Multi-Layered Acoustic Boards: An Apso And Sa Approach, Min-Chie Chiu, Ho-Chih Cheng

Journal of Marine Science and Technology–Taiwan

A high level of noise, combined with pure tones, is often encountered in ship's cabins, leading to severe psychological and physiological issues for the crew. To address this problem, an indoor noise abatement solution becomes necessary that utilizes efficient acoustic boards integrated with resonators, positioned along the inner walls of the cabin. However, the thickness of the acoustic boards must be strictly limited due to maintenance and operational considerations. This limitation results in insufficient sound absorption capabilities and a restricted range of tuned frequencies, as the resonating frequency of a standard Helmholtz resonator is closely tied to its cavity. A …

Numerical Study On The Aerodynamic Performance Of Four Flettner Rotors By Varying Distance And Spin Ratio, Janghoon Seo, Dong-Woo Park

Journal of Marine Science and Technology–Taiwan

The Flettner rotor is a wind-assisted propulsion system applied in eco-friendly ship to reduce greenhouse gas emissions. As the requirements of international regulations on greenhouse gas emissions become increasingly strict, multiple Flettner rotors are being applied, necessitating the evaluation of their performance with varying design parameters. The present study focuses on the aerodynamic performances of four Flettner rotors with variable design parameters of distance and spin ratio. Distances and spin ratios, including relative spin ratios, are considered. The drag and lift coefficients and lift-to-drag ratio of Flettner rotors are determined using Computational Fluid Dynamics (CFD), and the associated flow fields …

Underwater Image Enhancement Algorithm For Dual Color Spaces, Xingsheng Shen, Yalin Song, Shichang Li, Xiaoshu Hu

Journal of Marine Science and Technology–Taiwan

Targeting issues related to low contrast, blurring, and loss of detail prevalent in underwater image enhancement algorithms, we propose a dual-color space multiscale residual network (DMR-SCNet) based on SCNet. First, we introduce the HSV color space feature extraction module, which aims to optimize the color representation and saturation of underwater images. Subsequently, we propose the RGB color space denoising module, which focuses on repairing the content and structure of underwater images to enhance their clarity and visual quality. Finally, by designing the residual attention (RAB) module, we aim to further refine the detailed representation and feature extraction of underwater images. …

A Novel Identity Authentication Mechanism For Unmanned Maritime Vessels Communication Based On Mitre Att&Ck Framework, Junxian He, Shih-Hao Chang

Journal of Marine Science and Technology–Taiwan

With the development of the smart shipping industry, unmanned vessel technology is rapidly evolving, accompanied by a demand for robust Internet of Things (IoT) communication security practices. Key communication technologies for the operation of unmanned vessels include external vessel communication. One crucial aspect is the verification of the identities of the parties involved in these communication systems, as this ensures secure and trusted interactions between unmanned vessels and port management authorities. Identity authentication plays a vital role in ensuring the secure communication of unmanned vessels.This paper aims to analyze potential risks related to identity authentication technology in unmanned vessel communication …