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Engineering Management And Industrial Engineering Industry And Educational Workforce Development Strategy, Robert J. Gies, Resit Unal, Charles B. Keating Jan 2024

Engineering Management And Industrial Engineering Industry And Educational Workforce Development Strategy, Robert J. Gies, Resit Unal, Charles B. Keating

Engineering Management & Systems Engineering Faculty Publications

This paper provides an overview of the development and resulting product of a collaborative industry-academia engineering management and industrial engineering workforce development strategy. In the spring of 2017, Old Dominion University's (ODU) Engineering Management and Systems Engineering Department (EMSE) approached Newport News Shipbuilding (NNS) with a concept to develop an educational initiative to support the preparation and development of the future workforce. The concept came to fruition over the next two years as a certification program in Engineering Systems and Industrial Engineering for NNS working professionals. This paper examines the primary aspects of the development of the certification program. Emphasis …

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System Of Systems Engineering: A Literature Review And Research Frontiers, Charles B. Keating, Polinpapilinho F. Katina, James C. Pyne Jan 2024

System Of Systems Engineering: A Literature Review And Research Frontiers, Charles B. Keating, Polinpapilinho F. Katina, James C. Pyne

Engineering Management & Systems Engineering Faculty Publications

System of Systems Engineering (SoSE) has existed and been developing for well over 2 decades. The time is appropriate to take a reflective look at the past and examine the future evolution of this nascent field. To address this challenge, this paper is focused on two primary objectives. First, a literature review of the SoSE field is conducted. This literature review (1) organizes the SoSE body of knowledge and provides a synthesis of major crosscutting themes, and (2) provides a scholarly critique and identifies gaps in the current state of the SoSE field. The second objective is focused on providing …

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Navigating The Complexities Of Engineering Management: Insights Into Metrics, Measurements, And Pitfalls, Charles Daniels Jan 2024

Navigating The Complexities Of Engineering Management: Insights Into Metrics, Measurements, And Pitfalls, Charles Daniels

Engineering Management & Systems Engineering Faculty Publications

In the realm of Engineering Management, the reliance on metrics and measurements stands as a cornerstone for effective decision-making processes. These quantitative tools offer insights into performance dynamics and facilitate informed strategic choices. However, the uncritical application of metrics devoid of profound domain expertise presents significant challenges. This abstract explores the pitfalls inherent in utilizing metrics and measurements within Engineering Management without comprehensive understanding, emphasizing the potential consequences and proposing strategies for navigating this complex terrain.

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Exploring Hedonic And Utilitarian Aspects Through Perceived Warmth In Human-Designed Vs. Ai-Generated Fashion, Dooyoung Choi, Ha Kyung Lee Jan 2024

Exploring Hedonic And Utilitarian Aspects Through Perceived Warmth In Human-Designed Vs. Ai-Generated Fashion, Dooyoung Choi, Ha Kyung Lee

Educational Leadership & Workforce Development Faculty Publications

Among various ways in which artificial intelligence (AI) is used in the fashion industry, its utilization in design has sparked public discussion about the potential replacement of human designers by AI. Along with this critical question, it is imminent to examine how consumers would respond to designs by AI. The purpose of this study is to explore consumers’ perceptions toward a fashion product labeled as generated by an AI system, comparing it to the same product labeled as designed by a human designer. Specifically, drawing from existing literature, we examine if the design source affects consumers’ perceptions of a product …

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Smart Learning Development Model Of Indonesian Higher Education, Jajat Sudrajat, Widodo Samyono Jan 2024

Smart Learning Development Model Of Indonesian Higher Education, Jajat Sudrajat, Widodo Samyono

Mathematics & Statistics Faculty Publications

This research aims to provide input to the Entrepreneurship Study Program to improve the learning process in the context of accelerating National Entrepreneurship so that it can be implemented in 59 Entrepreneurship Study Programs that are members of the apski.net, as a follow-up to the Focus Group Discussion with members of APSKI and KEMENKOPEKM. The research method used in this study is the Research and Development (R&D) method through a case study of the intelligent learning process in the Entrepreneurship Study Program, Bina Nusantara University (Binus). The result of this research is that the Entrepreneurship Study Program can brand entrepreneurship …

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Latent Space Dynamics Learning For Stiff Collisional-Radiative Models, Xuping Xie, Qi Tang, Xianzhu Tang Jan 2024

Latent Space Dynamics Learning For Stiff Collisional-Radiative Models, Xuping Xie, Qi Tang, Xianzhu Tang

Mathematics & Statistics Faculty Publications

In this work, we propose a data-driven method to discover the latent space and learn the corresponding latent dynamics for a collisional-radiative (CR) model in radiative plasma simulations. The CR model, consisting of high-dimensional stiff ordinary differential equations, must be solved at each grid point in the configuration space, leading to significant computational costs in plasma simulations. Our method employs a physics-assisted autoencoder to extract a low-dimensional latent representation of the original CR system. A flow map neural network is then used to learn the latent dynamics. Once trained, the reduced surrogate model predicts the entire latent dynamics given only …

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Cats, Dogs, And Roll Waves, John Adam Jan 2024

Cats, Dogs, And Roll Waves, John Adam

Mathematics & Statistics Faculty Publications

This article discusses the phenomenon of roll waves, which are shock-like patterns separated by smooth profiles that occur in flood waves. The author mentions that in a steady-state situation, the drag forces on the water in the channel are balanced by the down-slope gravitational force. The article also includes questions for readers to estimate the speed and length of the roll waves, as well as determine the stability of the flow. The author provides additional information about the Chezy formula, an empirical equation used in fluid mechanics to estimate the mean flow velocity of open channel flow.

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Open-Access Publishing In Special Education And Related Fields, Esther R. Lindström, Jesse I. Fleming, Danika Pfeiffer, Tamara Kalandadze, Bryan G. Cook Jan 2024

Open-Access Publishing In Special Education And Related Fields, Esther R. Lindström, Jesse I. Fleming, Danika Pfeiffer, Tamara Kalandadze, Bryan G. Cook

Speech-Language Pathology Faculty Publications

Open access to research findings, syntheses of research, and papers providing guidance on implementing research-based practices is critical for informing policy and practice in special education and related fields. Yet most published articles are behind paywalls and cannot be accessed freely by many practitioners, policymakers, individuals with disabilities and their families, and other interested parties. In this article, we describe the benefits of open-access publishing for researchers and research consumers, as well as different types of open-access publishing–with a particular focus on self-archiving or green open-access publishing. Self-archiving makes papers freely available, with little time burden and no monetary cost …

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Tapped In: The Rise Of Mobile Malware, Chrystofuer Davenport Jan 2024

Tapped In: The Rise Of Mobile Malware, Chrystofuer Davenport

Cybersecurity Undergraduate Research Showcase

As the world of technology continues to evolve and become more advanced with our life, so do the dangers and threats that are determined to hinder that development. Malware continues to be a danger to internet surfers or people with access to technology. At first it was an issue that existed only with computers but since the evolution of smartphones in the early twenty-first century, mobile devices have been a target for multiple malware viruses. It’s important to be aware of what different viruses are capable of doing and how to avoid them when they are encountered. Even though computers …

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Charge Lifetime Improvement Of The Continuous Electron Beam Accelerator Facility Photogun With A Biased Anode, J. T. Yoskowitz, G. A. Krafft, G. Palacios-Serrano, S.A.K. Wijethunga, J. Grames, J. Hansknecht, C. Hernandez-Garcia, M. Poelker, M. L. Stutzman, R. Suleiman, C. A. Valerio-Lizarraga, S. B. Van Der Geer Jan 2024

Charge Lifetime Improvement Of The Continuous Electron Beam Accelerator Facility Photogun With A Biased Anode, J. T. Yoskowitz, G. A. Krafft, G. Palacios-Serrano, S.A.K. Wijethunga, J. Grames, J. Hansknecht, C. Hernandez-Garcia, M. Poelker, M. L. Stutzman, R. Suleiman, C. A. Valerio-Lizarraga, S. B. Van Der Geer

Physics Faculty Publications

GaAs photocathodes in dc high-voltage photoguns are highly susceptible to ion back-bombardment, which reduces the photocathode quantum efficiency and limits the useful operating lifetime for producing polarized electron beams. This paper demonstrates that applying a small positive bias to the photogun anode can significantly suppress ion back-bombardment and increase charge lifetime. This technique was studied extensively using the Continuous Electron Beam Accelerator Facility photogun, where highly polarized electron beams created using a strained-superlattice GaAs/GaAsP photocathode were used and charge lifetimes improved by almost a factor of 2. A new simulation code ionator was developed to model ion production and tracking …

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Automatic Hemorrhage Segmentation In Brain Ct Scans Using Curriculum-Based Semi-Supervised Learning, Solayman H. Emon, Tzu-Liang (Bill) Tseng, Michael Pokojovy, Peter Mccaffrey, Scott Moen, Md Fashiar Rahman Jan 2024

Automatic Hemorrhage Segmentation In Brain Ct Scans Using Curriculum-Based Semi-Supervised Learning, Solayman H. Emon, Tzu-Liang (Bill) Tseng, Michael Pokojovy, Peter Mccaffrey, Scott Moen, Md Fashiar Rahman

Mathematics & Statistics Faculty Publications

One of the major neuropathological consequences of traumatic brain injury (TBI) is intracranial hemorrhage (ICH), which requires swift diagnosis to avert perilous outcomes. We present a new automatic hemorrhage segmentation technique via curriculum-based semi-supervised learning. It employs a pre-trained lightweight encoder-decoder framework (MobileNetV2) on labeled and unlabeled data. The model integrates consistency regularization for improved generalization, offering steady predictions from original and augmented versions of unlabeled data. The training procedure employs curriculum learning to progressively train the model at diverse complexity levels. We utilize the PhysioNet dataset to train and evaluate the proposed approach. The performance results surpass those of …

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Inexact Fixed-Point Proximity Algorithm For The ℓ₀ Sparse Regularization Problem, Ronglong Fang, Yuesheng Xu, Mingsong Yan Jan 2024

Inexact Fixed-Point Proximity Algorithm For The ℓ₀ Sparse Regularization Problem, Ronglong Fang, Yuesheng Xu, Mingsong Yan

Mathematics & Statistics Faculty Publications

We study inexact fixed-point proximity algorithms for solving a class of sparse regularization problems involving the ℓ₀ norm. Specifically, the ℓ₀ model has an objective function that is the sum of a convex fidelity term and a Moreau envelope of the ℓ₀ norm regularization term. Such an ℓ₀ model is non-convex. Existing exact algorithms for solving the problems require the availability of closed-form formulas for the proximity operator of convex functions involved in the objective function. When such formulas are not available, numerical computation of the proximity operator becomes inevitable. This leads to inexact iteration algorithms. We investigate in this …

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Addressing Spectral Bias Of Deep Neural Networks By Multi-Grade Deep Learning, Ronglong Fang, Yuesheng Xu Jan 2024

Addressing Spectral Bias Of Deep Neural Networks By Multi-Grade Deep Learning, Ronglong Fang, Yuesheng Xu

Mathematics & Statistics Faculty Publications

Deep neural networks (DNNs) have showcased their remarkable precision in approximating smooth functions. However, they suffer from the spectral bias, wherein DNNs typically exhibit a tendency to prioritize the learning of lower-frequency components of a function, struggling to effectively capture its high-frequency features. This paper is to address this issue. Notice that a function having only low frequency components may be well-represented by a shallow neural network (SNN), a network having only a few layers. By observing that composition of low frequency functions can effectively approximate a high-frequency function, we propose to learn a function containing high-frequency components by composing …

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Sscm: A Secured Approach To Supply Chain Management Using Blowfish Optimization, Shitharth Selvarajan, Hariprasath Manoharan, Alaa O. Khadidos, Achyut Shankar, Adil O. Khadidos, Wattana Viriyasitavat, Li Da Xu Jan 2024

Sscm: A Secured Approach To Supply Chain Management Using Blowfish Optimization, Shitharth Selvarajan, Hariprasath Manoharan, Alaa O. Khadidos, Achyut Shankar, Adil O. Khadidos, Wattana Viriyasitavat, Li Da Xu

Information Technology & Decision Sciences Faculty Publications

This study examines the importance of enterprise information systems that link several corporate organisations to share information about diverse products under high security settings. The primary goal of the proposed strategy is to create a direct link between product demand and production to minimise the impact of rising costs. The research motive to make a connection cannot be resolved without suitable data that shows both quantity and quality in each organisation unit. The suggested method is designed to deliver accurate data to authorised end users while preventing any data exposure to unauthorised users. Security cryptographic keys are utilised to create …

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Translational Neuroscience Contributes To Understanding Neurodevelopmental Outcomes Of Dostoyevsky's "Brothers Karamazov" With Treatment Implications, Stephen I. Deutsch, Jessica A. Burket, Jeffrey Elikan Jd, David R. Spiegel Jan 2024

Translational Neuroscience Contributes To Understanding Neurodevelopmental Outcomes Of Dostoyevsky's "Brothers Karamazov" With Treatment Implications, Stephen I. Deutsch, Jessica A. Burket, Jeffrey Elikan Jd, David R. Spiegel

Department Psychiatry & Behavioral Science Faculty Publications

Dostoyevsky's novels raise profound ethical, moral, philosophical and theological issues and, as a result, both he and his novels serve as fertile subjects of scholarly inquiry across a variety of academic disciplines. In particular, major characters in "The Brothers Karamazov" lend themselves to classical psychodynamic formulations, such as the influence of adverse childhood experiences on adult social and occupational outcomes, which in the case of Dmitry, the eldest son of Fyodor Pavlovich Karamazov, are considered in exquisitely fine detail. Prosecutor and defense attorney provide differing interpretations of how early traumas, largely due to paternal neglect and abuse, affected Dmitry's adult …

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Energy Harvesting Face Mask Using A Thermoelectric Generator For Powering Wearable Health Monitoring Sensors, Ugur Erturun, Cansu Yalim, James E. West Jan 2024

Energy Harvesting Face Mask Using A Thermoelectric Generator For Powering Wearable Health Monitoring Sensors, Ugur Erturun, Cansu Yalim, James E. West

Engineering Management & Systems Engineering Faculty Publications

A wearable energy harvester (EH) incorporating a face mask with a thermoelectric generator is demonstrated. The function of this device is to generate electrical power from the heat produced by the human body, particularly breath, with the specific aim of powering wearable sensor applications. A prototype was built using a commercially available N95 face mask, a thermoelectric generator, and a heatsink. The performance of this EH device was assessed using experimental and numerical methodologies. The experimentally tested power output of the prototype was found to be ≈100 µW, with a corresponding power density of ≈30 µW/cm3, for a temperature difference …

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Asem 4.0/5.0 - Evolving The Engineering Management Profession Through Industry 4.0/5.0 Collaborative Networks, T. Steven Cotter, Faisal Mahmud, Ziniya Zahedi Jan 2024

Asem 4.0/5.0 - Evolving The Engineering Management Profession Through Industry 4.0/5.0 Collaborative Networks, T. Steven Cotter, Faisal Mahmud, Ziniya Zahedi

Engineering Management & Systems Engineering Faculty Publications

The American Society for Engineering Management was created and matured under Industry 3.0 automation. The emergence of Industry 4.0 and 5.0 are forcing all organizational sectors to rethink their long-term strategy with respect to emerging horizontal/vertical cyber-physical systems integration. This leaves open the question of the directions in which ASEM should evolve into the 21st century. This paper reports an initial mapping of Industry 4.0 and 5.0 technologies and initiatives as goal-oriented, long-term strategic collaborative networks. The research method began with the Boston Consulting Group nine technologies of Industry 4.0 (2015) and the Industry 5.0 technologies within its human-centric, sustainability, …

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Montana As Place Of (Un)Belonging: Landscape, Identity, And The American West In Bella Vista (2014), Najmeh Moradiyan-Rizi Jan 2024

Montana As Place Of (Un)Belonging: Landscape, Identity, And The American West In Bella Vista (2014), Najmeh Moradiyan-Rizi

Communication & Theatre Arts Faculty Publications

The American West is not just a geographical terrain but a mythical construct that occupies a powerful place in the popular imagination thanks to myriad literary and artistic works that have presented the region through specific archetypes emphasizing its vast ruggedness, white masculinity, and unique Americanness. In recent decades, revisionist scholarly and artistic works, however, have attempted to offer more nuanced perspectives on the region challenging its assumed homogenous history and fixed and stable identity. In particular, women filmmakers have recast the region through multifaceted representations underlining its complexity, diversity, and transnational dimensions. This article analyzes Vera Brunner-Sung’s film Bella …

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Undergraduate Research On 5g Propagation Analysis In Naval Ship Environment, Otilia Popescu, Dimitrie Popescu, Murat Kuzlu Jan 2024

Undergraduate Research On 5g Propagation Analysis In Naval Ship Environment, Otilia Popescu, Dimitrie Popescu, Murat Kuzlu

Engineering Management & Systems Engineering Faculty Publications

Wireless communication systems have experienced rapid advancements over the last decade, with 5G systems becoming the regular standards and 6G systems being under development. However, the naval ship environment still requires more study due to the special indoor characteristics of the spaces below the deck, where the metal structures strongly impact the propagation characteristics, being prone to signal degradation, dead spots, and unreliable connectivity. This paper presents the research work conducted by a team of undergraduate students from Electrical and Computer Engineering (ECE) and Electrical Engineering Technology (EET) majors. The work was a partnership between Old Dominion University engineering programs …

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Selecting And Evaluating Key Mds-Updrs Activities Using Wearable Devices For Parkinson's Disease Self-Assessment, Yuting Zhao, Xulong Wang, Xiyang Peng, Ziheng Li, Fengtao Nan, Menghui Zhuo, Jun Qi, Yun Yang, Zhong Zhao, Lida Xu, Po Yang Jan 2024

Selecting And Evaluating Key Mds-Updrs Activities Using Wearable Devices For Parkinson's Disease Self-Assessment, Yuting Zhao, Xulong Wang, Xiyang Peng, Ziheng Li, Fengtao Nan, Menghui Zhuo, Jun Qi, Yun Yang, Zhong Zhao, Lida Xu, Po Yang

Information Technology & Decision Sciences Faculty Publications

Parkinson's disease (PD) is a complex neurodegenerative disease in the elderly. This disease has no cure, but assessing these motor symptoms will help slow down that progression. Inertial sensing-based wearable devices (ISWDs) such as mobile phones and smartwatches have been widely employed to analyse the condition of PD patients. However, most studies purely focused on a single activity or symptom, which may ignore the correlation between activities and complementary characteristics. In this paper, a novel technical pipeline is proposed for fine-grained classification of PD severity grades, which identify the most representative activities. We also propose a multi-activities combination scheme based …

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Dihydroethidium-Derived Fluorescence In Electrically Stressed Cells Indicates Intracellular Microenvironment Modifications Independent Of Ros, Esin B. Sözer, Iurii Semenov, P. Thomas Vernier Jan 2024

Dihydroethidium-Derived Fluorescence In Electrically Stressed Cells Indicates Intracellular Microenvironment Modifications Independent Of Ros, Esin B. Sözer, Iurii Semenov, P. Thomas Vernier

Bioelectrics Publications

Intracellular reactive oxygen species (ROS) generation is widely suggested as a trigger for biological consequences of electric field exposures, such as those in electroporation applications. ROS are linked with membrane barrier function degradation, genetic damage, and complex events like immunological cell death. Dihydroethidium (DHE) is commonly used to monitor ROS in cells. DHE is linked to intracellular ROS by a primary oxidation product, Ethidium (Eth+), that shows increased fluorescence upon binding to polynucleotides. We observed changes in DHE-derived fluorescence in Chinese hamster ovary (CHO) cells post 300-ns electric pulse exposures, comparing them to tert-butyl-hydroperoxide (t-BHP) induced oxidative stress. …

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Synergistic Effects Of Nanosecond Pulsed Plasma And Electric Field On Inactivation Of Pancreatic Cancer Cells In Vitro, Edwin A. Oshin, Zobia Minhas, Ruben M. L. Colunga Biancatelli, John D. Catravas, Richard Heller, Siqi Guo, Chunqi Jiang Jan 2024

Synergistic Effects Of Nanosecond Pulsed Plasma And Electric Field On Inactivation Of Pancreatic Cancer Cells In Vitro, Edwin A. Oshin, Zobia Minhas, Ruben M. L. Colunga Biancatelli, John D. Catravas, Richard Heller, Siqi Guo, Chunqi Jiang

Bioelectrics Publications

Nanosecond pulsed atmospheric pressure plasma jets (ns-APPJs) produce reactive plasma species, including charged particles and reactive oxygen and nitrogen species (RONS), which can induce oxidative stress in biological cells. Nanosecond pulsed electric field (nsPEF) has also been found to cause permeabilization of cell membranes and induce apoptosis or cell death. Combining the treatment of ns-APPJ and nsPEF may enhance the effectiveness of cancer cell inactivation with only moderate doses of both treatments. Employing ns-APPJ powered by 9 kV, 200 ns pulses at 2 kHz and 60-nsPEF of 50 kV/cm at 1 Hz, the synergistic effects on pancreatic cancer cells (Pan02) …

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Submarine Groundwater Discharge At A Mega-Tidal Beach, Raymond D. Craddock, Aaron A. Mohammed, Joseph J. Tamborski, Barret L. Kurylyk Jan 2024

Submarine Groundwater Discharge At A Mega-Tidal Beach, Raymond D. Craddock, Aaron A. Mohammed, Joseph J. Tamborski, Barret L. Kurylyk

OES Faculty Publications

Tidally influenced groundwater systems in coastal environments represent important mixing zones of fresh groundwater and circulating seawater, manifesting as submarine groundwater discharge (SGD). Water circulation induced by tidal pumping enhances the exchange of chemicals between aquifers and coastal waters and thereby influences the biogeochemistry of coastal zones. Here, we report the results of an SGD field study conducted at a steep, mega-tidal sand and gravel beach along the Canadian coast of the Bay of Fundy, a region with the world's highest tides (semi-diurnal tidal ranges exceeding 10 m). Several physical and geochemical measurement techniques were employed to document the spatiotemporal …

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A Comparison Of Adenosine Triphosphate With Other Metrics Of Microbial Biomass In A Gradient From The North Atlantic To The Chesapeake Bay, Alexander B. Bochdansky, Amber A. Beecher, Joshua R. Calderon, Alison N. Stouffer, Nyjaee N. Washington Jan 2024

A Comparison Of Adenosine Triphosphate With Other Metrics Of Microbial Biomass In A Gradient From The North Atlantic To The Chesapeake Bay, Alexander B. Bochdansky, Amber A. Beecher, Joshua R. Calderon, Alison N. Stouffer, Nyjaee N. Washington

OES Faculty Publications

A new, simplified protocol for determining particulate adenosine triphosphate (ATP) levels allows for the assessment of microbial biomass distribution in aquatic systems at a high temporal and spatial resolution. A comparison of ATP data with related variables, such as particulate carbon, nitrogen, chlorophyll, and turbidity in pelagic samples, yielded significant and strong correlations in a gradient from the tributaries of the Chesapeake Bay (sigma-t = 8) to the open North Atlantic (sigma-t = 29). Correlations varied between ATP and biomass depending on the microscopic method employed. Despite the much greater effort involved, biomass determined by microscopy correlated poorly with other …

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A Proxy System Modeling Approach To Combining Tree-Ring And Sediment-Based Paleotempestological Records, Elizabeth J. Wallace, Sylvia Dee, Joshua Bregy, Kerry A. Emanuel Jan 2024

A Proxy System Modeling Approach To Combining Tree-Ring And Sediment-Based Paleotempestological Records, Elizabeth J. Wallace, Sylvia Dee, Joshua Bregy, Kerry A. Emanuel

OES Faculty Publications

The short and biased observational record of tropical cyclones (TCs) limits scientific understanding of how these destructive storms respond to climate forcing. Paleohurricane records use natural archives (tree rings, coarse-grained sediment) to reconstruct TC properties (frequency and intensity of rainfall, wind) over the past few hundreds to thousands of years. However, different sensitivities and sampling biases in the various paleohurricane proxies restrict our ability to compile these records into regional or basin-scale TC estimates. Here we test how well pseudo tree-ring records of paleohurricanes capture TC rainfall and occurrence. Using a large set of statistically downscaled storms forced with the …

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Contrasting Nitrogen Dynamics Across The Mid-Atlantic Bight Shelfbreak Front: Insights From Nitrate Dual Isotopes And Nitrifier Gene Abundance, Yifan Zhu, Margaret R. Mulholland, Corday R. Selden, Dennis J. Mcgillicuddy Jr., Josie Mottram, P. Dreux Chappell, Weifang Gordon Zhang, Julie Granger, Katherine E. Crider, Meredith G. Meyer, Peter W. Bernhardt, Hilde Oliver, Sophie Clayton Jan 2024

Contrasting Nitrogen Dynamics Across The Mid-Atlantic Bight Shelfbreak Front: Insights From Nitrate Dual Isotopes And Nitrifier Gene Abundance, Yifan Zhu, Margaret R. Mulholland, Corday R. Selden, Dennis J. Mcgillicuddy Jr., Josie Mottram, P. Dreux Chappell, Weifang Gordon Zhang, Julie Granger, Katherine E. Crider, Meredith G. Meyer, Peter W. Bernhardt, Hilde Oliver, Sophie Clayton

OES Faculty Publications

Observations and model studies suggest that front dynamics can enhance phytoplankton productivity. This study tested whether frontal systems also increase the abundance of nitrifying microbes and nitrogen recycling during repeat sampling transects across the Mid‐Atlantic Bight shelfbreak in July 2019. We measured ammonium concentrations, nitrate dual isotopes (δ15N, δ18O), and ammonia monooxygenase subunit A (amoA) genes of ammonia‐oxidizing archaea (AOA) and bacteria (AOB). In subsurface shelf waters, ammonium concentrations exceeded 2 μmol L−1, due to a temporary imbalance in regeneration from sinking particles and subsequent nitrification. The inverse correlation between nitrate δ15 …

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Widespread Crab Burrows Enhance Greenhouse Gas Emissions From Coastal Blue Carbon Ecosystems, Kai Xiao, Yuchen Wu, Feng Pan, Yingrong Huang, Hebo Peng, Meiqing Lu, Yan Zhang, Hailong Li, Yan Zheng, Chunmiao Zheng, Yan Liu, Nengwan Chen, Leilei Xiao, Guangxuan Han, Yasong Li, Pei Xin, Ruili Li, Bochao Xu, Faming Wang, Joseph J. Tamborski, Alicia M. Wilson, Daniel M. Alongi, Isaac R. Santos Jan 2024

Widespread Crab Burrows Enhance Greenhouse Gas Emissions From Coastal Blue Carbon Ecosystems, Kai Xiao, Yuchen Wu, Feng Pan, Yingrong Huang, Hebo Peng, Meiqing Lu, Yan Zhang, Hailong Li, Yan Zheng, Chunmiao Zheng, Yan Liu, Nengwan Chen, Leilei Xiao, Guangxuan Han, Yasong Li, Pei Xin, Ruili Li, Bochao Xu, Faming Wang, Joseph J. Tamborski, Alicia M. Wilson, Daniel M. Alongi, Isaac R. Santos

OES Faculty Publications

Fiddler crabs, as coastal ecosystem engineers, play a crucial role in enhancing biodiversity and accelerating the flow of material and energy. Here we show how widespread crab burrows modify the carbon sequestration capacity of different habitats across a large climatic gradient. The process of crab burrowing results in the reallocation of sediment organic carbon and humus. Crab burrows can increase more greenhouse gases emissions compared to the sediment matrix (CO2: by 17-30%; CH4: by 49-141%). Straightforward calculations indicate that these increased emissions could offset 35-134% of sediment carbon burial in these two ecosystems. This research highlights the complex interactions between …

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Mechanics Of Pure Bending And Eccentric Buckling In High-Strain Composite Structures, Jimesh D. Bhagatji, Oleksandr G. Kravchenko, Sharanabasaweshwara Asundi Jan 2024

Mechanics Of Pure Bending And Eccentric Buckling In High-Strain Composite Structures, Jimesh D. Bhagatji, Oleksandr G. Kravchenko, Sharanabasaweshwara Asundi

Mechanical & Aerospace Engineering Faculty Publications

To maximize the capabilities of nano- and micro-class satellites, which are limited by their size, weight, and power, advancements in deployable mechanisms with a high deployable surface area to packaging volume ratio are necessary. Without progress in understanding the mechanics of high-strain materials and structures, the development of compact deployable mechanisms for this class of satellites would be difficult. This paper presents fabrication, experimental testing, and progressive failure modeling to study the deformation of an ultra-thin composite beam. The research study examines the deformation modes of a post-deployed boom under repetitive pure bending loads using a four-point bending setup and …

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Comprehensive Static And Dynamic Modeling Of A Magnetic Suspension And Balance System, Colin P. Britcher, Caleb Hull, David Cox, Mark Schoenenberger Jan 2024

Comprehensive Static And Dynamic Modeling Of A Magnetic Suspension And Balance System, Colin P. Britcher, Caleb Hull, David Cox, Mark Schoenenberger

Mechanical & Aerospace Engineering Faculty Publications

Magnetic Suspension and Balance Systems (MSBS) are inherently complex multi-degree-of-freedom dynamic systems. Comprehensive, high-fidelity dynamic models are increasingly important due to the application of model-based controllers as well as demands for unsteady aerodynamic data derived from post-test system identification. This paper reviews some aspects of the development of a dynamic model of the NASA/ODU 6-inch MSBS.

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Restoration Of Strength In Polyamide Woven Glass Fiber Organosheets By Hot Pressing, Mohammad Nazmus Saquib, Edwing Chaparro-Chavez, Christopher Morris, Kuthan Çelebi, Diego Pedrazzoli, Mingfu Zhang, Sergii G. Kravchenko, Oleksandr G. Kravchenko Jan 2024

Restoration Of Strength In Polyamide Woven Glass Fiber Organosheets By Hot Pressing, Mohammad Nazmus Saquib, Edwing Chaparro-Chavez, Christopher Morris, Kuthan Çelebi, Diego Pedrazzoli, Mingfu Zhang, Sergii G. Kravchenko, Oleksandr G. Kravchenko

Mechanical & Aerospace Engineering Faculty Publications

Thermoplastic composite organosheets (OSs) are increasingly recognized as a viable solution for automotive and aerospace structures, offering a range of benefits including cost-effectiveness through high-rate production, lightweight design, impact resistance, formability, and recyclability. This study examines the impact response, post-impact strength evaluation, and hot-pressing repair effectiveness of woven glass fiber nylon composite OSs across varying impact energy levels. Experimental investigations involved subjecting composite specimens to impact at varying energy levels using a drop-tower test rig, followed by compression-after-impact (CAI) tests. The results underscore the exceptional damage tolerance and improved residual compressive strength of the OSs compared to traditional thermoset composites. …

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