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2025

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Ai-Driven Electromagnetic Design And Performance Prediction Of Microstrip Antennas, Eduardo Javier Vazquez Dec 2025

Ai-Driven Electromagnetic Design And Performance Prediction Of Microstrip Antennas, Eduardo Javier Vazquez

Theses and Dissertations

This thesis investigates the application of Deep Learning to automate and accelerate microstrip antenna inverse design. The initial investigation was to predict microstrip antenna performance from its geometry parametric input, and found out that forward prediction with adopted geometric representation results in ill-posed scenario, high ambiguity and unstable mapping. The study later mostly focuses on the inverse prediction by machine learning from S11 parameter input to predict antenna patch geometry parameters instead.

A dataset of 5,000 ANSYS HFSS simulated antennas (later filtered to 4,136 valid samples) was generated using cubic spine -described geometry profiles. Multiple neural architectures were adopted for …


Seagrass Preference Among Pinfish In The Lower Laguna Madre, Nathaniel Garza Dec 2025

Seagrass Preference Among Pinfish In The Lower Laguna Madre, Nathaniel Garza

Theses and Dissertations

Pinfish (Lagodon rhomboides) is a common estuarine fish species found from Massachusetts to the Yucatan, Mexico. As juveniles, pinfish spend a significant portion of their life in coastal seagrasses which provide both shelter from predators and food. Along the Texas coast, there are three major species of seagrass- turtle grass (Thalassia testudinum), manatee grass (Syringodium filiforme) and shoal grass (Halodule wrightii) that differ in structural complexity. The goal of this study was to determine if pinfish associate more with one seagrass species than the others. A year-long field study was completed using twelve sample sites in the Lower Laguna Madre, …


Connections On Manifolds: A Modern Approach To Classical Differential Geometry, Jed Allen Wilshire Dec 2025

Connections On Manifolds: A Modern Approach To Classical Differential Geometry, Jed Allen Wilshire

Theses and Dissertations

The purpose of this thesis is to connect modern differential geometry concepts to the classical differential geometry study of surfaces, specifically spheres. This thesis will cover the topics of Riemannian manifolds, tangent spaces, vectors, vector fields, the connection of Levi-Civita, the Christoffel symbols, and Riemannian curvature. Each concept will be demonstrated on the well known unit sphere manifold.


Development And Testing Of A Prototype Erbium-Doped Lithium Tantalate Based Sensor For Infrastructure Crack Detection And Measurement, Alejandro Barrera Dec 2025

Development And Testing Of A Prototype Erbium-Doped Lithium Tantalate Based Sensor For Infrastructure Crack Detection And Measurement, Alejandro Barrera

Theses and Dissertations

Ensuring the safety and longevity of infrastructure is crucial to safeguarding communities and preserving economic stability. In this study, the development of a novel sensor for detecting and characterizing cracks in infrastructure, particularly suited for deployment on Unmanned Aerial Vehicles (UAVs), is presented. The device utilizes a laser (operating at 980 nm) for excitation of erbium-doped lithium tantalate nanoparticles that emit 1550 nm wavelength, which stimulates a photodiode for data collection. The data was utilized to collect, process, and reconstruct topological information. The synthesized lithium tantalate nanoparticle samples vary in erbium doping percentages of 0.5%, 3%, and 10%. Experimental evaluation …


Population Structure Of Red Drum (Sciaenops Ocellatus (Linnaeus, 1766)) In Two Systems In The Northwestern Gulf Of Mexico, Sandra Antonia Leal Dec 2025

Population Structure Of Red Drum (Sciaenops Ocellatus (Linnaeus, 1766)) In Two Systems In The Northwestern Gulf Of Mexico, Sandra Antonia Leal

Theses and Dissertations

Red drum (Sciaenops ocellatus) are an economically significant species of fish inhabiting the Gulf of Mexico. There are limited studies assessing S. ocellatus population structure focused on the southern coast of Texas. A total of 1,008 fish were collected over one year on a quarterly basis at South Bay (SB) and Holly Beach (HB) in the Lower Laguna Madre (LLM) of Texas to assess population structure. Juvenile S. ocellatus utilize the water systems of the LLM as a nursery ground and were more abundant at SB (n = 718) than HB (n = 290). The most abundant age classes were …


A Computational Approach To Ramanujan-Type Congruences For Products Of Level 13, Aiden Michael Lalonde Dec 2025

A Computational Approach To Ramanujan-Type Congruences For Products Of Level 13, Aiden Michael Lalonde

Theses and Dissertations

In this thesis, we find products that are modular forms of level 13 whose Fourier coefficients satisfy certain congruences. These products are constructed in terms of integer powers of Klein forms and the Dedekind eta function. The products that are modular forms for Γ1 (13) have vectors of exponents that are elements of a bounded polytope. A parameterization for this polytope allows us to find a complete set of products that are modular forms for Γ1 (13). The corresponding graded ring of modular forms containing these products is constructed from a finite set of generators. These generators satisfy a finite …


Postprocessing Gan-Generated Synthetic Time Series Using Dynamic Time Warping, Md Raisul Islam Roni Dec 2025

Postprocessing Gan-Generated Synthetic Time Series Using Dynamic Time Warping, Md Raisul Islam Roni

Electronic Theses and Dissertations

Generative Adversarial Networks (GANs) are a class of deep learning models capable of producing realistic synthetic data that preserve the statistical and temporal characteristics of real datasets. The DoppelGANger (DGAN) framework extends this approach to time series data by jointly modeling temporal dependencies and contextual metadata. However, synthetic sequences generated by GAN may show temporal misalignment, resulting in inconsistencies when compared with real data. This study presents a postprocessing framework based on Dynamic Time Warping (DTW) and its differentiable extension Soft-DTW to improve the temporal alignment of synthetic time series. The framework is evaluated using quantitative measures of alignment and …


Microgrid Approach With Data-Driven Monitoring To Enhance The Resilience Of Water Distribution Systems, Binod Ale Magar Dec 2025

Microgrid Approach With Data-Driven Monitoring To Enhance The Resilience Of Water Distribution Systems, Binod Ale Magar

Theses

Existing centralized water supply systems are critically threatened by the joint effects of climate and socioeconomic changes, extreme weather events, and physical degradation due to aging, and their changeability. The uncertain and changing drivers pose challenges for water supply systems in providing sustainable water services during disruptions. The energy field dealing related issues has endorsed the microgrid approach with a decentralized energy supply with dispersed local energy sources. The application of energy microgrids has demonstrated their resiliency for sustainable energy supply. For improved resiliency of a water distribution system, this study investigated the application of a microgrid approach and the …


Investigating Mariculture-Associated Ecosystem Services Across The Northern Gulf Of Alaska, Josianne Haag Dec 2025

Investigating Mariculture-Associated Ecosystem Services Across The Northern Gulf Of Alaska, Josianne Haag

Oceanography

The rapid expansion of mariculture in Alaska can drive physical and chemical alterations to the marine environment by introducing non-native organisms or artificially increasing the biomass of a native species. Currently, the main mariculture products grown in Alaska include the Pacific oyster (Crassostrea gigas), the Pacific blue mussel (Mytilus trosuslus), and three macroalgae species: ribbon kelp (Alaria marginata), sugar kelp (Saccharina latissima), and bull kelp (Nereocystis luetkeana). This dissertation examines how these species can impact their surrounding environment to better inform management practices for this growing industry. This research characterized the resource use of C. gigas and M. trossulus seasonally …


Information Without Rents: Mechanism Design Without Expected Utility, Ernesto Rivera Mora, Philipp Strack Dec 2025

Information Without Rents: Mechanism Design Without Expected Utility, Ernesto Rivera Mora, Philipp Strack

Cowles Foundation Discussion Papers

We study mechanism design for a sophisticated agent with non-expected utility (EU) preferences. We show that the revelation principle holds if and only if all types are EU maximizers: if at least one type is a non-EU maximizer, randomizing over dynamic mechanisms generates a strictly larger set of implementable allocations than using static mechanisms. Moreover, dynamic stochastic mechanisms can fully extract the private information of any type who doesn’t have uniformly quasi-concave preferences without providing that type any rent. Full-surplus extraction is possible in a broad variety of non-EU environments, but impossible for types with concave preferences.


Streams Guidelines: Standards For Technical Reporting In Environmental And Host-Associated Microbiome Studies, Julia M. Kelliher, Chloe Mirzayi, Sarah R. Bordenstein, Aaron Oliver, Christina A. Kellogg, Eneida L. Hatcher, Maureen Berg, Petr Baldrian, Mashael Aljumaah, Cassandra Maria Luz Miller, Christopher Mungall, Vlastimil Novak, Alexis Palucki, Ethan Smith, Nazifa Tabassum, Gregory Bonito, J. Rodney Brister, Patrick S. Chain, Mingfei Chen, Samuel Degregori, Xuefeng Peng, Et. Al. Dec 2025

Streams Guidelines: Standards For Technical Reporting In Environmental And Host-Associated Microbiome Studies, Julia M. Kelliher, Chloe Mirzayi, Sarah R. Bordenstein, Aaron Oliver, Christina A. Kellogg, Eneida L. Hatcher, Maureen Berg, Petr Baldrian, Mashael Aljumaah, Cassandra Maria Luz Miller, Christopher Mungall, Vlastimil Novak, Alexis Palucki, Ethan Smith, Nazifa Tabassum, Gregory Bonito, J. Rodney Brister, Patrick S. Chain, Mingfei Chen, Samuel Degregori, Xuefeng Peng, Et. Al.

Faculty Publications

The interdisciplinary nature of microbiome research, coupled with the generation of complex multi-omics data, makes knowledge sharing challenging. The Strengthening the Organization and Reporting of Microbiome Studies (STORMS) guidelines provide a checklist for the reporting of study information, experimental design and analytical methods within a scientific manuscript on human microbiome research. Here, in this Consensus Statement, we present the standards for technical reporting in environmental and host-associated microbiome studies (STREAMS) guidelines. The guidelines expand on STORMS and include 67 items to support the reporting and review of environmental (for example, terrestrial, aquatic, atmospheric and engineered), synthetic and non-human host-associated microbiome …


Definition Of The 3d Position And Motion Status Of The Moving Heart Based On 2d Projections, Lawrence D. Orijuela Dec 2025

Definition Of The 3d Position And Motion Status Of The Moving Heart Based On 2d Projections, Lawrence D. Orijuela

Electronic Theses, Projects, and Dissertations

This thesis presents a novel application of deep learning to the estimation of pulmonary vein coordinates using X-ray image pairs from a FORBILD Thorax phantom derived motion dataset. A Siamese neural network was developed to predict the 3D coordinates of one pulmonary vein at a time, specifically the Right Superior Pulmonary Vein (RSPV), Left Superior Pulmonary Vein (LSPV), Left Inferior Pulmonary Vein (LIPV), or Right Inferior Pulmonary Vein (RIPV), based on two-dimensional projection images.

The input data consisted of over 1.6 million grayscale X-ray image pairs across 1331 virtual patients, each annotated with ground truth 3D coordinates. To manage memory …


East Antarctic Ice Sheet History At The Outback Nunataks Using Geographic Information Systems And Cosmogenic Dating, Jacob P. Baker Dec 2025

East Antarctic Ice Sheet History At The Outback Nunataks Using Geographic Information Systems And Cosmogenic Dating, Jacob P. Baker

Electronic Theses, Projects, and Dissertations

This study investigates the history of ice sheet surface elevation at the Outback Nunataks in East Antarctica using exposure age dating and geomorphic mapping. We identified glacial landforms at Roberts Butte, Miller Butte, and Frontier Mountain, in the Outback Nunatak range, using 2023 Landsat Image Mosaic of Antarctica (LIMA) and 2022 Reference Elevation Model of Antarctica (REMA). We collected bedrock and glacial erratic samples for cosmogenic nuclide analysis from Roberts Butte and Miller Butte during the 2023-24 United States Antarctic Program field season. Analysis of glacial erratics reflect inherited cosmogenic nuclide concentrations, resulting in apparent exposure ages between 359 and …


Groundwater Arsenic Contamination In The Oro Grande Wash, Dalila Boice Dec 2025

Groundwater Arsenic Contamination In The Oro Grande Wash, Dalila Boice

Electronic Theses, Projects, and Dissertations

This study investigates the distribution of naturally occurring arsenic in groundwater within the Oro Grande Wash in San Bernardino County, California. Depth-discrete groundwater quality data were collected over multiple years using nested and Westbay monitoring wells. Water quality results showed higher levels of arsenic in the deeper aquifers, ranging between 600 feet and 1,000 feet below ground surface. Arsenic levels in these regions reached as high as 66 µg/L. At roughly 800 feet and below, water quality data from the wells reveal that arsenic concentrations exceeded the 10 µg/L maximum contaminant level (MCL) in 87% of cases. These data provide …


Teacher Perceptions Of The Effectiveness Of Voluntary Pre-Kindergarten Attendance, Kimberly Taylor Dec 2025

Teacher Perceptions Of The Effectiveness Of Voluntary Pre-Kindergarten Attendance, Kimberly Taylor

Electronic Theses and Dissertations

The purpose of this study was to identify the perceptions of educators with respect to student enrollment in voluntary pre-kindergarten classes provided through the Tennessee Department of Education in public schools. The data collection strategy used to gain teacher perspectives was through conducting one-on-one interviews with 15 educators in three Tennessee school districts. To qualify for the study, teachers must have been teaching in kindergarten classrooms that receive students who had previously been enrolled in the school’s pre-kindergarten program. Data collection and analysis were based on the Grounded Theory approach which uses data that is systematically gained and analyzed to …


A Leslie System For A Demographic Simulation: From An Actuarial Point Of View, David Kings Dec 2025

A Leslie System For A Demographic Simulation: From An Actuarial Point Of View, David Kings

Electronic Theses and Dissertations

This thesis develops a discrete stochastic linear systems interpretation of age–stage demographic evolution grounded in Leslie operators and realized in a discrete-event simulation implemented with salabim. The central claim is that one annual cycle of the simulation constitutes a cone-preserving, stochastic affine transformation on a high- dimensional population state vector indexed by age, sex, marital status, household type, employment, and education, and that the composition of yearly operators yields a random matrix product whose top Lyapunov exponent is the stochastic counterpart of the Perron–Frobenius growth rate (Caswell, 2001; Tuljapurkar, 1997)[1, 2]. The actuarial bridge is constructed by mapping simulated survival …


Isolation, Chemical Characterization, And In-Vitro Cytotoxic Evaluation Of Novel Polar Flavonoids From Chromolaena Leivensis, Matthew Tohatsu Tetteh Dec 2025

Isolation, Chemical Characterization, And In-Vitro Cytotoxic Evaluation Of Novel Polar Flavonoids From Chromolaena Leivensis, Matthew Tohatsu Tetteh

Electronic Theses and Dissertations

This study focuses on isolation, chemical characterization, and in-vitro cytotoxic evaluation of novel polar flavonoids from chromolaena leivensis. A 95% ethanolic extract of c. leivensis shipped by Prof. Ruben Torrenegra from University of Applied and Environmental Sciences, Bogota, Colombia, was dissolved in 1:1 methanol/chloroform mixture and its purity analyzed by TLC. The sample was eluted with toluene/methanol in an increasing order of polarity on silica gel, resulting in 49 fractions labelled CLA1 to CLA49. Among these fractions, CLA10 (1) and CLA19 (2) obtained yellow and white crystals. They were analyzed by GCMS, IR, and …


High-School-Age Youth Serving As “Emotion Coaches” For Young Children In The Early Grades: A Feasibility Study Of A Cross-Age Approach To Social And Emotional Learning, Amanda Moreno, Maria Kontoudakis, Whitney Davis-Mcintosh, Anita Evans, Olivia Bobbitt Dec 2025

High-School-Age Youth Serving As “Emotion Coaches” For Young Children In The Early Grades: A Feasibility Study Of A Cross-Age Approach To Social And Emotional Learning, Amanda Moreno, Maria Kontoudakis, Whitney Davis-Mcintosh, Anita Evans, Olivia Bobbitt

Journal of Youth Development

While the benefits of cross-age programming within youth have been understood for decades, such programs are rarely employed with curricula specific to social and emotional learning (SEL) or with a wide age range between the two groups of youth. This article describes the findings of a pilot implementation and feasibility study of the Emotion Coaches program, which sought to explore whether the conceptual and pragmatic challenges involved in bringing early childhood students (i.e., preschool to second grade) together with adolescent teachers delivering an SEL curriculum could be overcome. Findings from the pilot evaluation suggested that middle-school-age students are likely too …


From Principles To Protection: Leadership In Uniting Integrity And Ethics For Research Security, Seán Lacey, Tom Farrelly, Tara Doherty, Suzanne Mcmurphy, Áine De Róiste Dec 2025

From Principles To Protection: Leadership In Uniting Integrity And Ethics For Research Security, Seán Lacey, Tom Farrelly, Tara Doherty, Suzanne Mcmurphy, Áine De Róiste

Publications

In today's global research landscape, ensuring integrity and security is critical. The CORRIE - Collaborative Open Resources on Research Integrity and Ethics - project brought together an international, multidisciplinary, cross-jurisdictional team to develop practical principles and resources for research integrity and ethics. Using a values-driven, collaborative leadership model, the team co-created tools grounded in authenticity and accountability, establishing an actionable framework. These resources should effectively address research security, fostering a resilient, effective research culture. Through a user-informed methodology and inclusive collaboration, the project team translated principles into tangible tools reinforcing ethical conduct in daily practice. This approach ensures robust protections …


Sme Cyber Resilience State Of The Sector 2025, Hazel Murray, Gillian O'Carroll, Aoibheann Brangan, Jason Holland, Stephanie Chevanne Wallace, Miriam Curtain, Glenda Deveney Dec 2025

Sme Cyber Resilience State Of The Sector 2025, Hazel Murray, Gillian O'Carroll, Aoibheann Brangan, Jason Holland, Stephanie Chevanne Wallace, Miriam Curtain, Glenda Deveney

Department of Computer Science Publications

Ireland's small and medium enterprises (SMEs) face a critical cyber resilience gap. SMEs account for 99.8% of all enterprises in Ireland and employ over 2.29 million people, representing 67.9% of total employment (based on the latest CSO 2022 figures). This cyber resilience assessment reveals that the majority of SMEs remain underprepared for modern cyber threats.


Labor Transportation Simulation And Optimization - A Case Study, Tala Taha Dec 2025

Labor Transportation Simulation And Optimization - A Case Study, Tala Taha

Theses

Transportation systems play a critical role in supporting economic activity, workforce mobility, and service delivery in urban and industrial environments. In many organizations, fixed-time transportation systems are essential for ensuring that employees are transferred from accommodation facilities to work locations within strict operational time windows. The case study company in this research operates a large-scale labour transport service between multiple accommodation camps and client sites in Dubai. Historically, buses were dispatched in an ad hoc manner, relying on supervisors’ experience rather than a systematic planning approach. This often led to low seat utilisation, unnecessarily long routes, higher fuel costs, and …


Predicting Inmate Overcrowding To Improve Facility Management, Mayed Ali Alameri Dec 2025

Predicting Inmate Overcrowding To Improve Facility Management, Mayed Ali Alameri

Theses

Overcrowding is a major challenge to correction systems because the conventional forecasting techniques are inaccurate and inadequate in most cases. This paper will solve this by constructing and testing a machine learning-based model to predict facility-level overcrowding. With the use of the XGBoost Regressor model on a dataset comprising of U.S. correctional facilities, the research identified key structural drivers but showed that the static facility attributes alone have limited predictive power (r-square approx 0.18) The discussion shows that overcrowding is non-linear, and a complicated problem not confined to the facility characteristics but to the larger, non-measurable regional influences, of which …


Optimizing Waste Management And Recycling Patterns Using Data Analytics, Mohammad Omar Almarri Dec 2025

Optimizing Waste Management And Recycling Patterns Using Data Analytics, Mohammad Omar Almarri

Theses

The increasing pace of urbanisation and consumption has increased the burden of waste generation in the world and it is a huge burden on the current waste management systems. The United Arab Emirates (UAE) is a region that is intensifying this challenge through the accelerated urbanization, high sustainability targets, and the necessity of effective recycling policies. The thesis that is being examined explores the ways in which the data analytics can be utilized to streamline waste management and recycling trends, emphasizing the enhancement of the collection process, forecasting the trends in the waste generation as well as facilitating the use …


Investigating The Role Of Motivation On The Effectiveness Of Computerized Cognitive Training Among At-Risk Youth, Emely N. Lugo Dec 2025

Investigating The Role Of Motivation On The Effectiveness Of Computerized Cognitive Training Among At-Risk Youth, Emely N. Lugo

Electronic Theses, Projects, and Dissertations

Student motivation plays a central role in academic success, influencing persistence, engagement, and performance across grade levels. Within situated expectancy-value theory (SEVT), motivation is shaped by students’ beliefs about their ability to succeed (expectancy), the importance or usefulness they assign to a task (value), the perceived effort or trade-offs involved (cost), and the situational context in which learning occurs. Although the link between motivation and academic performance is well known, there is limited research on how motivational factors, like those proposed by SEVT, influence the extent of cognitive gains from school-based cognitive interventions designed to improve abilities related to academic …


Interactions Between Black, Brown, Blue And Green Carbon From Terrestrial To Marine Ecosystems: A Critical Review, Allison White, Richard Kline, Md. Saydur Rahman Dec 2025

Interactions Between Black, Brown, Blue And Green Carbon From Terrestrial To Marine Ecosystems: A Critical Review, Allison White, Richard Kline, Md. Saydur Rahman

School of Earth, Environmental, & Marine Sciences Faculty Publications

Black and brown carbon are byproducts of the incomplete combustion of biomass or fossil fuels. These light-absorbing aerosols influence climate by altering the radiative balance through the absorption and scattering of sunlight, exacerbating global climate change. Their subsequent deposition on terrestrial and marine environments affects surface albedo, snow and ice melt, and biogeochemical processes, leading to further environmental consequences. In contrast, green and blue carbon refer to carbon stored in terrestrial vegetation and marine ecosystems, respectively. These ecosystems play a crucial role in mitigating climate change by sequestering atmospheric carbon; however, they are increasingly threatened by climatic disturbances, anthropogenic activities, …


Leptinotarsa Texana Schaeffer And Gargaphia Arizonica Drake & Carvalho As Potential Biocontrol Agents For The Noxious Weed Solanum Elaeagnifolium Cav, Samikshya Subedi, Stephanie L. Kasper, Alexis Racelis, Greg Lefoe, Rupesh R. Kariyat Dec 2025

Leptinotarsa Texana Schaeffer And Gargaphia Arizonica Drake & Carvalho As Potential Biocontrol Agents For The Noxious Weed Solanum Elaeagnifolium Cav, Samikshya Subedi, Stephanie L. Kasper, Alexis Racelis, Greg Lefoe, Rupesh R. Kariyat

School of Earth, Environmental, & Marine Sciences Faculty Publications

Silverleaf nightshade (Solanum elaeagnifolium Cav.; SLN) is a perennial forb native to the southern United States, Mexico and South America that has become a serious agricultural weed across the world. Biological control has emerged as a significant alternative for the management of (SLN) due to the challenges and high costs associated with chemical and mechanical controls. In this study, we used a combination of field and laboratory studies to (1) explore the fundamental and realized host ranges of two North American insects, Leptinotarsa texana Schaeffer and Gargaphia arizonica Drake & Carvalho and (2) assess their suitability as potential biological …


Integrating Semi-Supervised Learning And Ensemble Deep Learning For Low-Resource Deep Knowledge Tracing, Uchechukwu Melody Okechukwu Dec 2025

Integrating Semi-Supervised Learning And Ensemble Deep Learning For Low-Resource Deep Knowledge Tracing, Uchechukwu Melody Okechukwu

All Theses

As learning platforms scale, two obstacles prevent Deep Knowledge Tracing (DKT) from thriving in practice: the scarcity of labeled interactions and the opacity of predictions. We introduced a semi-supervised, ensemble DKT pipeline that trains diverse architectures, including Knowledge Proficiency Tracing (KPT), Exercise-Correlated KPT (EKPT), and Dynamic Key-Value Memory Networks (DKVMN) on a mixture of limited labeled and abundant unlabeled learner interactions, then aggregates predictions via majority voting to stabilize learning and reduce variance. Evaluated on benchmark datasets such as ASSISTments, the combined approach yields consistent gains in AUC, accuracy, and precision over strong supervised baselines while revealing influential interactions, surfacing …


Modeling And Control Of Spring-Mass Systems With Switched Dynamics Using Reservoir Computing, Osemudiamen Andrew Ihimekpen Dec 2025

Modeling And Control Of Spring-Mass Systems With Switched Dynamics Using Reservoir Computing, Osemudiamen Andrew Ihimekpen

All Theses

Hybrid spring-mass systems with dynamic state switching present significant challenges for modeling and control due to their complex nonlinear dynamics and discrete state transitions. In this research, a novel reservoir computing framework based on echo-state networks (ESNs) was proposed to model and control spring-mass systems with two distinct states: F1 (without air friction) and F2 (with air friction). The system switched between states based on velocity thresholds, creating a complex, hybrid dynamic that required sophisticated modeling approaches. The proposed method enabled efficient learning of spatiotemporal patterns in hybrid dynamics, offering accurate system identification and robust control capabilities.

The framework was …


Spatial–Temporal Evolution Of The Box Springs Plutonic Complex, Riverside, Ca, Mateo Ospino Díaz Dec 2025

Spatial–Temporal Evolution Of The Box Springs Plutonic Complex, Riverside, Ca, Mateo Ospino Díaz

Loma Linda University Electronic Theses, Dissertations & Projects

The mechanisms of pluton emplacement into continental crust have long been debated in igneous geology, with early models emphasizing forceful processes such as ballooning, later contrasted by alternative emplacement mechanisms including diapirism, incremental assembly, stoping and, emplacement by sheets and dikes. These contrasting perspectives highlight the complexity of the construction of mid-crustal intrusions and the need for case studies that integrate multiple datasets. The Box Springs Plutonic Complex (BSPC) in the northern Peninsular Ranges Batholith (PRB) preserves structural, textural, and compositional features that record its emplacement and internal construction. Although its lithology, structure, and geochemistry have been described, an integrated …


Climatology, Seasonality, And Extremes Of Fires In Alaska's Boreal And Tundra Regions Using The Initial Spread Index, Jacob Coffey Dec 2025

Climatology, Seasonality, And Extremes Of Fires In Alaska's Boreal And Tundra Regions Using The Initial Spread Index, Jacob Coffey

Atmospheric Sciences

The Alaskan fire season is an increasingly consequential aspect of the state’s summer climate, with recent years frequently exceeding one million acres burned. Among the key factors influencing fire behavior, wind and moisture play a critical role in driving fire spread. The Initial Spread Index (ISI), a component of the Canadian Forest Fire Danger Rating System, quantifies the expected rate of fire spread following ignition. ISI is currently used operationally in Alaska. Despite its significance, ISI remains under-studied in terms of its historical behavior, trends, and environmental sensitivity. This study evaluates the climatology, variability, and trends of ISI across Alaska …