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A Comparison Of Gaussian Processes And Polynomial Chaos Emulators In The Context Of Haemodynamic Pulse–Wave Propagation Modelling, L. Mihaela Paun, Mitchel J. Colebank, Dirk Husmeier Oct 2024

A Comparison Of Gaussian Processes And Polynomial Chaos Emulators In The Context Of Haemodynamic Pulse–Wave Propagation Modelling, L. Mihaela Paun, Mitchel J. Colebank, Dirk Husmeier

Faculty Publications

Computational modelling of the cardiovascular system is a promising future direction for patient-specific healthcare. However, the computational cost of these simulators is a bottleneck for their practical use in clinic for real-time digital twins. Emulation can overcome this, yet an extensive investigation into cardiovascular emulators is warranted. In this study, we emulate two one-dimensional haemodynamics models of the pulmonary circulation and compare two common emulation strategies: Gaussian processes (GPs) and polynomial chaos expansions (PCEs). We start by reducing the parameter space of the models through global sensitivity analysis, and then compare both emulation strategies using a multivariate, time-series output …


Aspect-Ratio-Dependent Heat Transport By Baroclinic Acoustic Streaming, Jacques Abdul Massih, Remil Mushthaq, Guillaume Michel, Gregory P. Chini Oct 2024

Aspect-Ratio-Dependent Heat Transport By Baroclinic Acoustic Streaming, Jacques Abdul Massih, Remil Mushthaq, Guillaume Michel, Gregory P. Chini

Faculty Publications

Standing acoustic waves have been known to generate Eulerian time-mean ‘streaming’ flows at least since the seminal investigation of Lord Rayleigh in the 1880s. Nevertheless, a recent body of numerical and experimental evidence has shown that inhomogeneities in the ambient density distribution lead to much faster flows than arise in classical Rayleigh streaming. The emergence of these unusually strong flows creates new opportunities to enhance heat transfer in systems in which convective cooling cannot otherwise be easily achieved. To assess this possibility, a theoretical study of acoustic streaming in an ideal gas confined in a rectangular channel with top and …


Aspect-Ratio-Dependent Heat Transport By Baroclinic Acoustic Streaming, Jacques Abdul Massih, Remil Mushthaq, Guillaume Michel, Gregory P. Chini Oct 2024

Aspect-Ratio-Dependent Heat Transport By Baroclinic Acoustic Streaming, Jacques Abdul Massih, Remil Mushthaq, Guillaume Michel, Gregory P. Chini

Faculty Publications

Standing acoustic waves have been known to generate Eulerian time-mean ‘streaming’ flows at least since the seminal investigation of Lord Rayleigh in the 1880s. Nevertheless, a recent body of numerical and experimental evidence has shown that inhomogeneities in the ambient density distribution lead to much faster flows than arise in classical Rayleigh streaming. The emergence of these unusually strong flows creates new opportunities to enhance heat transfer in systems in which convective cooling cannot otherwise be easily achieved. To assess this possibility, a theoretical study of acoustic streaming in an ideal gas confined in a rectangular channel with top and …


Hydrogen Underground Storage For Grid Electricity Storage: An Optimization Study On Techno-Economic Analysis, Yunzhi Chen, Daniel Hill, Blake Billings, John Hedengren, Kody Powell Oct 2024

Hydrogen Underground Storage For Grid Electricity Storage: An Optimization Study On Techno-Economic Analysis, Yunzhi Chen, Daniel Hill, Blake Billings, John Hedengren, Kody Powell

Faculty Publications

This study performs a techno-economic analysis of hydrogen underground storage systems for grid electricity storage, evaluating their economic viability at the plant scale using dynamic optimization. It explores the feasibility of various system configurations and revenue models in the context of volatile electricity prices and the necessity for multiple revenue streams. The hypothesis tested is that large-scale hydrogen storage, despite its low round-trip efficiency, can be economically viable with the right mix of revenue streams. This study uses scenario-based analysis to assess the impacts of different system configurations, including engaging in time-shifting arbitrage, ancillary service markets and blending hydrogen with …


The Provenance Of A Pali- And Thai-Language Manuscript At The Rollins College Library: A Buddhist Book Of Merit And Its Long Journey From Southeast Asia To America, Wenxian Zhang Oct 2024

The Provenance Of A Pali- And Thai-Language Manuscript At The Rollins College Library: A Buddhist Book Of Merit And Its Long Journey From Southeast Asia To America, Wenxian Zhang

Faculty Publications

Through researching the provenance of a Buddhist manuscript written in the Pali and Thai languages currently held at Rollins, this article seeks to answer the question of how a religious document created in Thailand ended up in a liberal arts college library in America. Regarded as an act of devotion by many Buddhist followers in Southeast Asia, the use of folding manuscripts (samut khoi) has been observed for centuries. The folding manuscripts served as handbooks and chanting manuals for Buddhist monks, who often recited in religious ceremonies while paying tributes to the deceased, with the hope of reincarnation in a …


Financial Impacts Of 2020 Labor Day Wildfires To Oregon Highways, Kevin Christiansen, Rubayet Bin Mostafiz, Ayat Al Assi, Robert V. Rohli, Carol J. Friedland Oct 2024

Financial Impacts Of 2020 Labor Day Wildfires To Oregon Highways, Kevin Christiansen, Rubayet Bin Mostafiz, Ayat Al Assi, Robert V. Rohli, Carol J. Friedland

Faculty Publications

Wildfire-caused damage to highways has a significant financial cost to the local, regional, and state jurisdictions where they occur. This study examines the financial ramifications of the harm caused to highways by megafires, using a case study of the highways impacted in the U.S. state of Oregon by the five megafires that occurred during the 2020 Labor Day wildfires. This study proposes a method to classify financial road damage from these wildfires based upon curated datasets collected from the Oregon Department of Transportation (ODOT). Hence, this study presents a dataset with labeled classes, which include physical, roadway, and traffic. Physical …


Innovation Challenges In The Air Force Sbir Program: From The Small Businesses’ Perspective, Hart J. Holt, Amy M. Cox, Scott Drylie, David S. Long, Alfred E. Thal Jr., R. David Fass Oct 2024

Innovation Challenges In The Air Force Sbir Program: From The Small Businesses’ Perspective, Hart J. Holt, Amy M. Cox, Scott Drylie, David S. Long, Alfred E. Thal Jr., R. David Fass

Faculty Publications

Every year the United States invests $3.2 billion in the Small Business Innovation Research (SBIR) program to promote innovation among the nation’s small businesses. Half of this investment is from the DoD. This research considers the challenges faced by small businesses innovating with the DoD, particularly those awarded SBIR contracts with the United States Air Force. The authors surveyed 286 unique small businesses that were previously awarded an Air Force SBIR contract. By asking the survey respondents open-ended questions and categorizing their responses, they pinpoint unaddressed challenges from the small business perspective. By categorizing survey responses through Qualitative Content Analysis, …


Production Box Cost Estimating Relationships For Dod Avionics, Carla J. Cisneros, Edward D. White, Brandon M. Lucas, Jonathan D. Ritschel, Robert D. Fass, Shawn M. Valentine Oct 2024

Production Box Cost Estimating Relationships For Dod Avionics, Carla J. Cisneros, Edward D. White, Brandon M. Lucas, Jonathan D. Ritschel, Robert D. Fass, Shawn M. Valentine

Faculty Publications

The authors use historical information obtained from the Cost Assessment Data Enterprise to estimate recurring production unit cost for DoD avionics via cost estimating relationships (CERs). The specific modeled responses include mean unit cost, median unit cost, and the 100th production unit cost (T100) utilizing learning curve theory. For T100, the authors adopt both a multiplicative and an additive error for CER comparison. Recommended CERs consist of the mean unit cost and the T100 utilizing a multiplicative error. Moreover, results reveal that weight has a significant effect on cost as well as a potential underaccounting of real price change or …


On Application Of A Surrogate Model To Numerical Evaluation Of Effective Elastic Properties Of Composites With 3d Rotationally Symmetric Particles, Pascal Alexander Happ, Igor Tsukrov, Romana Piat Oct 2024

On Application Of A Surrogate Model To Numerical Evaluation Of Effective Elastic Properties Of Composites With 3d Rotationally Symmetric Particles, Pascal Alexander Happ, Igor Tsukrov, Romana Piat

Faculty Publications

Micromechanical modelling of particulate composites with non-ellipsoidal particle shapes presents significant challenges because analytical approaches based on the fundamental results of Eshelby cannot be used. On the other side, direct numerical evaluations by finite element analysis can involve high computational cost in the case when particle features have small radius of curvature, sharp edges and require extremely fine meshes. This paper proposes substituting the exact particle shape with a surrogate model producing approximately the same contribution to the effective elastic moduli. We illustrate our approach by considering rotationally symmetric 3D particle shapes with the external surface defined by the Laplace's …


A Quantitative Adverse Outcome Pathway For Embryonic Activation Of The Aryl Hydrocarbon Receptor Of Fishes By Polycyclic Aromatic Hydrocarbons Leading To Decreased Fecundity At Adulthood, Jon A. Doering, Justin Dubiel, Eric Stock, Cameron H. Collins, Ian Frick, Hunter M. Johnson, Christopher M. Lowrey-Dufour, Justin G.P. Miller, Zhe Xia, Gregg T. Tomy, Steve Wiseman Oct 2024

A Quantitative Adverse Outcome Pathway For Embryonic Activation Of The Aryl Hydrocarbon Receptor Of Fishes By Polycyclic Aromatic Hydrocarbons Leading To Decreased Fecundity At Adulthood, Jon A. Doering, Justin Dubiel, Eric Stock, Cameron H. Collins, Ian Frick, Hunter M. Johnson, Christopher M. Lowrey-Dufour, Justin G.P. Miller, Zhe Xia, Gregg T. Tomy, Steve Wiseman

Faculty Publications

Quantitative adverse outcome pathways (qAOPs) describe the response–response relationships that link the magnitude and/or duration of chemical interaction with a specific molecular target to the probability and/or severity of the resulting apical-level toxicity of regulatory relevance. The present study developed the first qAOP for latent toxicities showing that early life exposure adversely affects health at adulthood. Specifically, a qAOP for embryonic activation of the aryl hydrocarbon receptor 2 (AHR2) of fishes by polycyclic aromatic hydrocarbons (PAHs) leading to decreased fecundity of females at adulthood was developed by building on existing qAOPs for (1) activation of the AHR leading to early …


Prescribed Fire Regimes Influence Responses Of Fungal And Bacterial Communities On New Litter Substrates In A Brackish Tidal Marsh, Viet Q. Dao, Crystal N. Johnson, William J. Platt Oct 2024

Prescribed Fire Regimes Influence Responses Of Fungal And Bacterial Communities On New Litter Substrates In A Brackish Tidal Marsh, Viet Q. Dao, Crystal N. Johnson, William J. Platt

Faculty Publications

Processes modifying newly deposited litter substrates should affect fine fuels in fire-managed tidal marsh ecosystems. Differences in chemical composition and dynamics of litter should arise from fire histories that generate pyrodiverse plant communities, tropical cyclones that deposit wrack as litter, tidal inundation that introduces and alters sediments and microbes, and interactions among these different processes. The resulting diversity and dynamics of available litter compounds should affect microbial (fungal and bacterial) communities and their roles in litter substrate dynamics and ecosystem responses over time. We experimentally examined effects of differences in litter types produced by different fire regimes and litter loads …


Comparative Transcriptomic Analyses Reveal Differences In The Responses Of Diploid And Triploid Eastern Oysters To Environmental Stress, Rujuta V Vaidya, Sarah Bodenstein, Dildorakhon Rasulova, Jerome F La Peyre, Morgan W Kelly Oct 2024

Comparative Transcriptomic Analyses Reveal Differences In The Responses Of Diploid And Triploid Eastern Oysters To Environmental Stress, Rujuta V Vaidya, Sarah Bodenstein, Dildorakhon Rasulova, Jerome F La Peyre, Morgan W Kelly

Faculty Publications

Triploid oysters are commonly used as the basis for production in the aquaculture of eastern oysters along the USA East and Gulf of Mexico coasts. While they are valued for their rapid growth, incidents of triploid mortality during summer months have been well documented in eastern oysters, especially at low salinity sites. We compared global transcriptomic responses of diploid and triploid oysters bred from the same three maternal source populations at two different hatcheries and outplanted to a high (annual mean salinity = 19.4 ± 6.7) and low (annual mean salinity = 9.3 ± 5.0) salinity site. Oysters were sampled …


Bipolar Membrane Capacitive Deionization For The Selective Capture Of Lithium Ions From Brines And Conversion To Lithium Hydroxide, Tanmay Kulkarni, Aliya Muhammad I. Al Dhamen, Xiaoliu Zhang, Chan Wen Chiu, Hanrui Zhang, Feifei Shi, Revati Kumar, Christopher G. Arges Oct 2024

Bipolar Membrane Capacitive Deionization For The Selective Capture Of Lithium Ions From Brines And Conversion To Lithium Hydroxide, Tanmay Kulkarni, Aliya Muhammad I. Al Dhamen, Xiaoliu Zhang, Chan Wen Chiu, Hanrui Zhang, Feifei Shi, Revati Kumar, Christopher G. Arges

Faculty Publications

Meeting the increasing demand for lithium in vehicle electrification and renewable energy storage requires innovations in lithium-ion (Li+) separations. Traditional solar evaporation methods for lithium recovery are slow and consume tremendous volumes of water and secondary chemicals (acids and bases). This study introduces a bipolar membrane capacitive deionization (BPM-CDI) unit for direct lithium extraction and LiOH production without the external addition of acids and bases. Utilizing de-lithiated lithium-iron-phosphate (LFP) coated carbon cloth electrodes, the BPM-CDI unit demonstrates selective Li+ capture over competing ions. Molecular dynamics simulations and H-cell experiments elucidate pH inversion mechanisms during Li+ release, …


Spatiotemporal Climatology Of Georgia Tropical Cyclones And Associated Rainfall, Reilly Corkran, Jill Trepanier, Vincent Brown Oct 2024

Spatiotemporal Climatology Of Georgia Tropical Cyclones And Associated Rainfall, Reilly Corkran, Jill Trepanier, Vincent Brown

Faculty Publications

Tropical cyclones (TCs), often characterized by high wind speeds and heavy rainfall, cause widespread devastation, affecting millions of people and leading to economic losses worldwide. TC-specific research in Georgia is scarce, likely due to the minimal geographical extent of its coast and the infrequency of direct landfalls. Research on Georgia TCs does not account for storms that make landfall in other southeastern states (e.g., Florida) and continue north, northeast, or northwest into Georgia. This study used the North Atlantic Basin hurricane database (HURDAT2) to quantify the spatiotemporal patterns of direct and indirect landfalling of Georgia tropical cyclones (>16 ms−1) …


Scene Classification Of Remote Sensing Image Based On Multi-Path Reconfigurable Neural Network, Wenyi Hu, Chunjie Lan, Tian Chen, Shan Liu, Lirong Yin, Lei Wang Oct 2024

Scene Classification Of Remote Sensing Image Based On Multi-Path Reconfigurable Neural Network, Wenyi Hu, Chunjie Lan, Tian Chen, Shan Liu, Lirong Yin, Lei Wang

Faculty Publications

Land image recognition and classification and land environment detection are important research fields in remote sensing applications. Because of the diversity and complexity of different tasks of land environment recognition and classification, it is difficult for researchers to use a single model to achieve the best performance in scene classification of multiple remote sensing land images. Therefore, to determine which model is the best for the current recognition classification tasks, it is often necessary to select and experiment with many different models. However, finding the optimal model is accompanied by an increase in trial-and-error costs and is a waste of …


Real-Time Synthesis Of A Nonuniformly Correlated, Partially Coherent Beam Using An Optical Coordinate Tansformation, Milo W. Hyde Iv Oct 2024

Real-Time Synthesis Of A Nonuniformly Correlated, Partially Coherent Beam Using An Optical Coordinate Tansformation, Milo W. Hyde Iv

Faculty Publications

We design, build, and validate an optical system for generating light beams with complex spatial coherence properties in real time. Beams of this type self-focus and are resistant to turbulence degradation, making them potentially useful in applications such as optical communications. We begin with a general theoretical analysis of our proposed design. Our approach starts by generating a Schell-model (uniformly correlated or shift-invariant) source by spatially filtering incoherent light. We then pass this light through an optical coordinate transformer, which converts the Schell-model source into a nonuniformly correlated field. After the general analysis, we discuss system engineering, including trade-offs among …


Scaling The Polymerization Of Polyaldehydes Through Continuous Flow Synthesis, Jared M. Schwartz, Paul A. Kohl, Anthony Engler Oct 2024

Scaling The Polymerization Of Polyaldehydes Through Continuous Flow Synthesis, Jared M. Schwartz, Paul A. Kohl, Anthony Engler

Faculty Publications

A plug flow reactor was constructed to scale the synthesis of metastable, phthalaldehyde-based polymers to achieve production rates of 1–2 kg per day. The flow-induced mixing and in-line polymerization quench and precipitation sequences resulted in improved polymer purity and long-term stability compared to the same materials made from a conventional batch process. Cryogenic rheology was used to probe the complex fluid dynamics encountered during the polymerization of PPA homopolymers. It is envisioned that this continuous flow manufacturing approach could be extended to other low ceiling temperature or aldehyde monomer systems to help implement and support a plastic circular economy. Graphical …


Technician Assignment In Multi-Shift Maintenance Schedules In An Offshore Wind Farm, Md Imran Hasan Tusar, Bhaba R. Sarker Oct 2024

Technician Assignment In Multi-Shift Maintenance Schedules In An Offshore Wind Farm, Md Imran Hasan Tusar, Bhaba R. Sarker

Faculty Publications

Offshore wind farms are becoming more and more important to sustainable energy strategies, yet their maintenance presents unique logistical challenges. The focus of this research is the Technician Assignment Problem (TAP) which involves a complicated and fluctuating scheduling problem. The key objective is to determine the most effective assignment of technicians to maintenance tasks to maximize operational efficiency and ensure reliable service. This study introduces a mathematical optimization model that processes numerous variables—technician availability, skill sets, and temporal constraints—to minimize unmet maintenance needs and ensure equitable workload distribution. The model is based on assumptions derived from actual operational conditions and …


Machine Learning For Automated Classification Of Lung Collagen In A Urethane-Induced Lung Injury Mouse Model, Khalid Hamad Alnafisah, Amit Ranjan, Sushant P. Sahu, Jianhua Chen, Sarah Mohammad Alhejji, Alexandra Noël, Manas Ranjan Gartia, Supratik Mukhopadhyay Oct 2024

Machine Learning For Automated Classification Of Lung Collagen In A Urethane-Induced Lung Injury Mouse Model, Khalid Hamad Alnafisah, Amit Ranjan, Sushant P. Sahu, Jianhua Chen, Sarah Mohammad Alhejji, Alexandra Noël, Manas Ranjan Gartia, Supratik Mukhopadhyay

Faculty Publications

Dysregulation of lung tissue collagen level plays a vital role in understanding how lung diseases progress. However, traditional scoring methods rely on manual histopathological examination introducing subjectivity and inconsistency into the assessment process. These methods are further hampered by inter-observer variability, lack of quantification, and their time-consuming nature. To mitigate these drawbacks, we propose a machine learning-driven framework for automated scoring of lung collagen content. Our study begins with the collection of a lung slide image dataset from adult female mice using second harmonic generation (SHG) microscopy. In our proposed approach, first, we manually extracted features based on the 46 …


Sustainability Of Asphalt Mixtures Containing 50% Rap And Recycling Agents, Ibrahim Elnaml, Louay N. Mohammad, Gaylon Baumgardner, Samuel Cooper, Samuel Cooper Oct 2024

Sustainability Of Asphalt Mixtures Containing 50% Rap And Recycling Agents, Ibrahim Elnaml, Louay N. Mohammad, Gaylon Baumgardner, Samuel Cooper, Samuel Cooper

Faculty Publications

The substitution of virgin asphalt binder with reclaimed asphalt pavement (RAP) has environmental and economic merits, however, cracking susceptibility arises due to the aged asphalt binder within RAP. The objectives of this study are to (1) enhance the cracking resistance of asphalt mixtures containing 50% RAP utilizing recycling agents (RAs) derived from six petroleum-based and bio-based materials, (2) conduct an environmental impact assessment (represented by global warming potential “GWP”) for high-RAP mixtures including RAs, and (3) estimate the cost effectiveness of including high-RAP content in asphalt mixtures. Based on the RAP asphalt binder performance grade (PG), base asphalt binder PG, …


Innovation Challenges In The Air Force Sbir Program: From The Small Businesses' Perspective, Hart J. Holt, Amy M. Cox, Scott Drylie, David S. Long, Alfred E. Thal Jr., Robert D. Fass Oct 2024

Innovation Challenges In The Air Force Sbir Program: From The Small Businesses' Perspective, Hart J. Holt, Amy M. Cox, Scott Drylie, David S. Long, Alfred E. Thal Jr., Robert D. Fass

Faculty Publications

Every year the United States invests $3.2 billion in the Small Business Innovation Research (SBIR) program to promote innovation among the nation’s small businesses. Half of this investment is from the DoD. This research considers the challenges faced by small businesses innovating with the DoD, particularly those awarded SBIR contracts with the United States Air Force. The authors surveyed 286 unique small businesses that were previously awarded an Air Force SBIR contract. By asking the survey respondents open-ended questions and categorizing their responses, they pinpoint unaddressed challenges from the small business perspective. By categorizing survey responses through Qualitative Content Analysis, …


High-Latitude Observations Of Dissipation-Range Turbulence By The Ulysses Spacecraft During The Solar Minimum Of 1993–96: The Spectral Break And Anisotropy, Abigale S. Watson, Charles W. Smith, Anastasia V. Marchuk, Matthew R. Argall, Colin J. Joyce, Philip A. Isenberg, Bernard J. Vasquez, Nathan A. Schwadron, Neil Murphy Oct 2024

High-Latitude Observations Of Dissipation-Range Turbulence By The Ulysses Spacecraft During The Solar Minimum Of 1993–96: The Spectral Break And Anisotropy, Abigale S. Watson, Charles W. Smith, Anastasia V. Marchuk, Matthew R. Argall, Colin J. Joyce, Philip A. Isenberg, Bernard J. Vasquez, Nathan A. Schwadron, Neil Murphy

Faculty Publications

We examine Ulysses magnetic field observations from 1993 to 1996 as the spacecraft made its first fast-latitude scan from the southern to the northern hemisphere. Most of the observations we use are representative of high-latitude solar minimum conditions. We examine magnetic field power spectra characteristics of interplanetary turbulence at high frequencies, where the spectrum breaks from an inertial range into the ion dissipation range. The onset and spectral index of the dissipation spectrum are consistent with low-latitude observations at 1 au. Both ranges have a ratio of power in perpendicular magnetic field components to parallel components near 3. The power …


In Situ Assembly Enabling Adhesive-Free Bonding Of Large Area Electronic Sensors To Concrete For Structural Health Monitoring, Emmanuel Ogunniyi, Han Liu, Austin Downey, Simon Laflamme, Caroline Bennett, William Collins, Hongki Jo, Paul Ziehl Oct 2024

In Situ Assembly Enabling Adhesive-Free Bonding Of Large Area Electronic Sensors To Concrete For Structural Health Monitoring, Emmanuel Ogunniyi, Han Liu, Austin Downey, Simon Laflamme, Caroline Bennett, William Collins, Hongki Jo, Paul Ziehl

Faculty Publications

Cracks developed in concrete infrastructure are one of the primary mechanisms that degrade their structural integrity, which may result in structural failures. Previous research on soft elastomeric capacitors (SEC) has shown their viability for structural health monitoring of structural materials, including concrete, steel, and fiberglass composites. The SEC, or its derivative version with a corrugated geometry termed corrugated SEC or cSEC, is a parallel plate capacitor. Prior work demonstrated that it was possible to directly paint the electrode interfacing with the structural material onto the structure and adhere the rest of the pre-fabricated sensor onto the wet interface, thereby eliminating …


On Application Of A Surrogate Model To Numerical Evaluation Of Effective Elastic Properties Of Composites With 3d Rotationally Symmetric Particles, Pascal Alexander Happ, Igor Tsukrov, Romana Piat Oct 2024

On Application Of A Surrogate Model To Numerical Evaluation Of Effective Elastic Properties Of Composites With 3d Rotationally Symmetric Particles, Pascal Alexander Happ, Igor Tsukrov, Romana Piat

Faculty Publications

Micromechanical modelling of particulate composites with non-ellipsoidal particle shapes presents significant challenges because analytical approaches based on the fundamental results of Eshelby cannot be used. On the other side, direct numerical evaluations by finite element analysis can involve high computational cost in the case when particle features have small radius of curvature, sharp edges and require extremely fine meshes. This paper proposes substituting the exact particle shape with a surrogate model producing approximately the same contribution to the effective elastic moduli. We illustrate our approach by considering rotationally symmetric 3D particle shapes with the external surface defined by the Laplace's …


Conducting Structure-From-Motion (Sfm) Modeling Of Freshwater Environments Using Unpiloted Aerial Systems (Uas): Challenges And Lessons Learned, Benjamin T. Fraser, Christine L. Bunyon, Russell G. Congalton Oct 2024

Conducting Structure-From-Motion (Sfm) Modeling Of Freshwater Environments Using Unpiloted Aerial Systems (Uas): Challenges And Lessons Learned, Benjamin T. Fraser, Christine L. Bunyon, Russell G. Congalton

Faculty Publications

The pairing of Unpiloted Aerial Systems (UAS) and Structure from Motion (SfM) has provided new capabilities for modeling freshwater environments. Applications of UAS-SfM range from water quality monitoring to the mapping of aquatic vegetation. The models produced provide users with the ability to analyze features at ultra-high-resolutions and across scales not easily achieved through in situ sampling. Despite the demonstrated benefits of UAS-SfM in freshwater and other natural resource disciplines, there remain fundamental technical challenges in the modeling of environments with homogenous surfaces (e.g., water). In this research, the effectiveness of several image collection and processing approaches for the modelling …


Lignin Cationization For The Removal Of Phosphates And Nitrates From Effluents Of Wastewater Treatment Plants, Fannyuy V. Kewir, Carlos E. Astete, Divine B. Nde, Jessica R. Eberhard, W. David Constant, Cristina M. Sabliov Sep 2024

Lignin Cationization For The Removal Of Phosphates And Nitrates From Effluents Of Wastewater Treatment Plants, Fannyuy V. Kewir, Carlos E. Astete, Divine B. Nde, Jessica R. Eberhard, W. David Constant, Cristina M. Sabliov

Faculty Publications

The removal of phosphates and nitrates from wastewater treatment plant (WWTP) effluents is important for preventing pollution of receiving waters. In this study, we chemically modified alkaline lignin (aLN) with quaternary ammonium groups to obtain biodegradable cationic lignin (cLN). We characterized the cLN and tested its efficacy for removing phosphates and nitrates in a lab setting and on field-collected WWTP samples. Adsorption isotherm and kinetic studies were performed in aqueous media, and the effects of several variables (contact time, pH, initial concentration, and adsorbent dose) were investigated. The Langmuir isotherm described phosphate and nitrate adsorption well, with R2 values of …


Flexible Operation Of Nuclear Hybrid Energy Systems For Load Following And Water Desalination, An Ho, Blake W. Billings, John Hedengren, Kody M. Powell Sep 2024

Flexible Operation Of Nuclear Hybrid Energy Systems For Load Following And Water Desalination, An Ho, Blake W. Billings, John Hedengren, Kody M. Powell

Faculty Publications

Nuclear hybrid energy systems (NHES) have the potential to provide dependable and emission-free electricity to the grid while also increasing the flexibility and reliability of the electrical grid. Molten salt reactor (MSR) technology can provide consistent, carbon-free electricity while also increasing efficiency, security, and sustainability and reducing nuclear waste. This study investigates the integration of Molten Salt Reactors (MSR) and conventional Pressurized Water Reactors (PWR) with desalination technologies: Direct Contact Membrane Distillation (DCMD), Multi-Stage Flash Distillation (MSFD), and Reverse Osmosis (RO). Dynamic first-principles models were developed and tested using real grid data from the New York Independent System Operator. The …


High-Fidelity Machine Learning Techniques For Driver Drowsiness Detection, Yasser Ismail, Ebenezer Essel, Abeer Abdelhamid, Mahmoud Darwich, Fahmi Khalifa, Fred Lacy Sep 2024

High-Fidelity Machine Learning Techniques For Driver Drowsiness Detection, Yasser Ismail, Ebenezer Essel, Abeer Abdelhamid, Mahmoud Darwich, Fahmi Khalifa, Fred Lacy

Faculty Publications

It is devastating that daily, there is an ample number of car crashes that cause damage to automobiles, onboard passengers get injured, and others tend to lose their lives. Road crashes are fast rising across the globe and have drawn many road safety commissions and concerned individuals to discuss ways to reduce this menacing situation drastically. With the introduction of artificial intelligence and technological advancement, the government and state commissions have beckoned on the various universities and research institutions to develop methods to curb the rise of automobile crashes. Some causes of these crashes include drunk driving and drowsiness, the …


Finite Element Modeling And Analysis Of Rc Shear Walls With Cutting-Out Openings, Islam M. Saad, Mohamed Emara, Ayman El-Zohairy, Sherif El-Beshlawy Sep 2024

Finite Element Modeling And Analysis Of Rc Shear Walls With Cutting-Out Openings, Islam M. Saad, Mohamed Emara, Ayman El-Zohairy, Sherif El-Beshlawy

Faculty Publications

In recent decades, reinforced concrete (RC) shear walls have been one of the best structural solutions to resist lateral load in high-rise buildings. Shear wall openings are essential for preparations and architectural requirements, which weaken the wall, reducing bearing capacity, energy absorption, and stiffness while also causing stress concentrations. This paper presents a comprehensive finite element (FE) investigation of the behavior and performance of RC shear walls with openings and subjected to lateral loads. The study aims to evaluate the influence of various parameters, such as opening location, size, wall aspect ratio, axial load, and concrete strength, which affect the …


The Evaluation Of Machine Learning Techniques For Isotope Identification Contextualized By Training And Testing Spectral Similarity, Aaron P. Fjelsted, Tyler J. Morrow, Clayton D. Scott, Yilun Zhu, Darren E. Holland, Azaree T. Lintereur, Douglas E. Wolfe Sep 2024

The Evaluation Of Machine Learning Techniques For Isotope Identification Contextualized By Training And Testing Spectral Similarity, Aaron P. Fjelsted, Tyler J. Morrow, Clayton D. Scott, Yilun Zhu, Darren E. Holland, Azaree T. Lintereur, Douglas E. Wolfe

Faculty Publications

Precise gamma-ray spectral analysis is crucial in high-stakes applications, such as nuclear security. Research efforts toward implementing machine learning (ML) approaches for accurate analysis are limited by the resemblance of the training data to the testing scenarios. The underlying spectral shape of synthetic data may not perfectly reflect measured configurations, and measurement campaigns may be limited by resource constraints. Consequently, ML algorithms for isotope identification must maintain accurate classification performance under domain shifts between the training and testing data. To this end, four different classifiers (Ridge, Random Forest, Extreme Gradient Boosting, and Multilayer Perceptron) were trained on the same dataset …