Digital Commons Network^™

Transitioning From The Consolidated Framework For Implementation Research (Cfir) To The Updated Cfir For Quantitative Measurement Of Influences On Implementation Outcomes In A Faith-Based Walking Intervention, Ruth P. Saunders, Sarah Wilcox Phd, A. Caroline Rudisill, Andrew T. Kaczynski, Jasmin Parker-Brown

Faculty Publications

Background Our research team has used the highly cited Consolidated Framework for Implementation Research (CFIR) a priori throughout the research process to better understand influences on implementation outcomes of an organizational change innovation to promote physical activity and healthy eating in faith-based settings. CFIR has recently been updated to include substantial changes in some domains and constructs, and our research team is preparing to carry out a new implementation study of an evidence-based innovation in churches. The purpose of this paper is to describe the process we undertook to map CFIR domains, constructs, and quantitative measures from our earlier studies …

Explaining Variability In Employee Perceptions Of Hr Practices In Strategic Hrm Research: An Integrative Review And Future Outlook, Jeske Van Beurden, Susanne Beijer, Kaifeng Jiang, Karina Van De Voorde, Anthony Nyberg

Faculty Publications

Employee perceptions of human resource (HR) practices have become a central focus in strategic human resource management(HRM) research due to their impact on individual and organizational outcomes. Recent studies highlight the importance of un-derstanding how these perceptions are formed, what they encompass, and why they vary across employees. This special issue ofHuman Resource Management aims to advance this evolving area of research by focusing on variability in employee perceptionsof HR practices. We review the current literature on employee perceptions of HR practices, including (1) theoretical and concep-tual clarity of the employee perceptions of HR practices construct, (2) antecedents of these …

Comprehensive, Multidisciplinary Care For Fragile X-Associated Tremor/Ataxia Syndrome, James A. Bourgeois, Andrea Schneider, Jessica Klusek Ph.D., Ccc-Slp, Thomas R. Christensen, Ellie Levin, Kendall Gardner, Ariel A. Jacobi, Randy J. Hagerman

Faculty Publications

Objective: 

The authors reviewed the pathophysiology, clinical genetics, phenotype, and comprehensive clinical management of Fragile X-associated Tremor/Ataxia Syndrome (FXTAS), a neurodegenerative disorder affecting FMR1 premutation carriers (55–200 CCG repeats).

Participants: 

A multispecialty and multidisciplinary team of authors with backgrounds in psychiatry, pediatrics, clinical psychology, speech and language pathology, and neurosciences.

Evidence: 

Review of English language sources on the clinical phenomenology, genetics, pathophysiology, and clinical management of FXTAS from 2001 (the original report) through 2025, with emphasis on the general medical, psychiatric, and neurological features of FXTAS and its multispecialty and multidisciplinary clinical management.

Consensus process:

All authors contributed to the …

Primary School Physical Activity Culture In The Uk: Findings From A Four-Month Rapid Ethnography In Three Schools, Robert Walker, Lydia Emm-Collison, Danielle House, Simoona Kent-Saisch, Ruth Salway, Alice Porter, Abi Howard, Tom Reid, Michael Beets Med, Mph, Phd, Frank De Vocht, Russell Jago

Faculty Publications

Introduction: Physical activity is fundamental for children’s health and well-being, yet most children are not active enough. School-based interventions aiming to increase children’s physical activity have largely been ineffective, perhaps due to a lack of consideration of the unique culture within each school. The aim of this paper is to understand the key aspects of physical activity culture in English primary schools using the organizational culture framework.

Methods: A four-month rapid ethnography study was conducted within three primary schools in Bristol, UK, between March and July 2024. The findings draw on observations, interviews, documentary data, photo elicitation, informal conversations and …

Examining The Relationships Between Students’ Achievement Goals And Their Academic Achievement In An Oer-Based Course: A Person-Centered Approach, Hengtao Tang Ph.D., Yan Yang, Yu Bao

Faculty Publications

Open Educational Resources (OER) have emerged as a cost-effective alternative to traditional commercial textbooks in higher education, towards the goal of alleviating college students’ financial burden of educational expenses. However, mixed findings about the influences of the integration of OER on student learning are present. To address the gap, this study investigated whether student motivation in OER served as a latent factor that impacts their academic achievement in online asynchronous courses offered in public universities. Particularly, this study (N = 247) implemented an advanced person-centered approach—stepwise latent class analysis—to profile student achievement goals in an OER-based course and examined their …

Social Network Determinants Of Cigarette Forgoing And Quit-Related Conversations In A 15-Day Ecological Momentary Assessment Study In Mexico And The Us, Lizeth Cruz-Jiménez, Kevin A. Carson, Jim Thrasher Ph.D., Ma, Ms, Katia Gallegos-Carrillo, Dèsirée Vidaña-Pérez, Diego F. Leal

Faculty Publications

Introduction

Methods

New Avenues For |Δb=2| Processes Beyond Neutron-Antineutron Oscillations, Arnau Basi Beneito, Svjetlana Fajfer, Alexey A. Petrov

Faculty Publications

We explore baryon-number-violating (|∆B| = 2) processes beyond the well-known neutron-antineutron (n-n̄) oscillations, focusing on the Λ-Λ̄ system. The presence of a strange quark in the Λ baryon introduces a new set of six-quark operators roughly of the form (uds)², which are different from the (udd)² operators responsible for n-n̄ oscillations. Using the Standard Model Effective Field Theory (SMEFT), we classify all dimension-9 operators that cause |∆B| = 2  transitions and study their UV completions mediated by exotic scalar fields with trilinear interactions. We demonstrate that …

Roadmap: Integrating Artificial Intelligence In Structural Health Monitoring Systems, Simon Laflamme, Erik Blasch, Flippo Ubertini, Zheng Liu, John Wertz, Christine Knott, Matthew Cherry, Eric Lindgren, Fu-Kuo Chang, Amrita Kumar, Jack Poole, Keith Worden, Austin Downey, Jie Wei, Patrick F. Musgrave, Adrian S. Wong, Guiseppe Quaranta, Marco Martino Rosso, Giuseppe Carlo Marano, Yu Chen, Et. Al.

Faculty Publications

Advances in computing and machine learning (ML) methods have led to a rapid rise in artificial intelligence (AI) research and applications in many fields. AI research benefitted from advances in computation hardware, collection and distribution of large data sets, and proliferation of software techniques. AI techniques include ML for provable results, deep learning for data exploration, reinforcement learning for control, and active learning for adaptive systems. Likewise, AI algorithms can handle large amounts of data, construct unknown representations, and provide a direct link between data and classification for decision making. These unmatched capabilities have been seen as a path to …

Efficient Energy-Stable Discontinuous Galerkin Schemefor The Non-Isothermal Cahn–Hilliard–Navier–Stokestwo-Phase Fluid Flow System, Guang-An Zou, Meiting Wang, Kejia Pan, Yin Yang, Xiaofeng Yang

Faculty Publications

In this article, we propose a novel numerical framework for the non-isothermal Cahn–Hilliard–Navier–Stokes two-phase flow system, which couples the incompressible Navier–Stokes equations, the Cahn–Hilliard phase-field equation, and the heat transport equation to capture temperature-dependent two-phase flow dynamics. The pro-posed scheme achieves three major advances: (i) unconditional energy stability through a combined scalar auxiliary variable (SAV) and zero-energy-contribution (ZEC) approach, (ii) linearity and full decoupling of all variables while using a second-order temporal discretization, and (iii) efficient implementation via discontinuous Galerkin (DG) spa-tial discretization together with a second-order projection method for the Navier–Stokes equations. We rigorously prove the unconditional energy stability …

Congruence Properties Modulo Prime Powers For A Class Of Partition Functions, Matthew Boylan, Swati .

Faculty Publications

Let p be prime, and let p_[1,p](n) denote the function whose generating function is

∏ _n≥1 (1 − qⁿ)⁻¹ (1 − q^pn)⁻¹.

This function and its generalizations p_[c^r,d^m](n) are the subject of study in several recent papers. Let ℓ ≥ 5, let j ≥ 1, and let p ∈ {2, 3, 5}. In this paper, we prove that the generating function for p_[1,p](n) in the progression β_{p,ℓ,j …}

Ulk4 And Cdkn2a Polymorphisms Influence The Risk Of Developing Monoclonal Gammopathy Of Undetermined Significance, José Manuuel Sánchez-Maldonado, Angelica Macauda, Antonio José Cabrera-Serrano, Hauke Thomsen, Murat Güler, Rob Ter Horst, Bethany Van Guelpen, Pavel Vodicka, Stefano Landi, Subhayan Chattopadhyay, Pelin Ünal, Lucía Ruiz-Durán, Delphine Casabonne, Hartmut Goldschmidt, Istemi Serin, María Carretero-Fernández, Elena Cabezudo, Fernando Reyes-Zurita, Alyssa I. Clay-Gilmour, Et. Al.

Faculty Publications

Monoclonal gammopathy of undetermined significance (MGUS) is a necessary precursor condition to multiple myeloma (MM). Given the role of autophagy in modulating MM risk, we investigated whether genetic variation in autophagy-related genes influences susceptibility to MGUS. We analyzed the association of 34,042 common autophagy-related single nucleotide polymorphisms (SNPs) with MGUS across six independent cohorts, five from Europe and one from North America, comprising 2317 MGUS cases and 282,358 controls. We also assessed their impact on immune parameters, including absolute counts of 91 blood-derived immune cell subsets and 103 circulating immunological proteins. Meta-analysis revealed a genome-wide significant association between the ULK4 …

Impact Of Medicaid Enrollment Timing On Tumor Stage At Diagnosis And Survival In Breast, Colorectal, And Lung Cancer, Gabriel A. Benavidez, Stella Coker Watson Self Ph.D., Ms, Anthony Alberg Ph.D., M.P.H., Janice Probst, Jan Marie Eberth

Faculty Publications

Background: Medicaid-insured patients experience higher rates of late-stage cancer diagnosis and worse survival than non-Medicaid patients. The impact of Medicaid enrollment timing on cancer outcomes is less clear. This study examines the association between Medicaid enrollment and timing with tumor stage and cancer-specific survival for breast, colorectal, and lung cancers. Methods: We analyzed SEER-Medicaid linked data for 276,755 breast, 104,784 colorectal, and 101,058 lung cancer patients < 65 years of age. Patients were categorized as non-Medicaid enrollees, pre-diagnosis enrollees (≥12 months before), or post-diagnosis enrollees (≤12 months after). Multivariable logistic regression estimated odds ratios of late-stage diagnosis, and cause-specific Cox proportional hazards models were used to assess cancer-specific survival, adjusting for demographic and socioeconomic factors. Results: Compared to non-Medicaid enrollees, post-diagnosis enrollees had the highest odds of late-stage diagnosis (breast cancer: OR: 3.41; colorectal cancer: OR: 3.78; lung cancer: OR: 1.87). Pre-diagnosis enrollees also had increased odds, but the …

A Collostructional Approach To The Concealed Passive Construction In English, Rok Sim, Jungsoo Kim

Faculty Publications

This study investigates the English concealed passive construction (CPC), as in the car needs washing, using authentic corpus data. While previous research has explored certain aspects of the CPC, little attention has been given to strongly associated matrix verbs (or verb types) and interactions between matrix verbs (or verb types) and other elements of the construction. To address these issues, we apply three types of collostructional analysis, and our findings indicate that no single, straightforward pattern emerges with respect to real-life grammatical properties of the CPC. We then show that the well-known distinction between raising and control constructions, formalized …

Moderate-Temperature Hydrothermal Treatment Removes Detectable Dna And Antibiotic Resistance Genes From Municipal Sludge While Preserving Resource Value, R Sean Norman M.Sc., Ph.D., Mirza Isanovic, Gabrielle Kartzmark, Nicole Berge

Faculty Publications

Wastewater treatment plants (WWTPs) are key reservoirs of antibiotic resistance genes (ARGs), with municipal sludge containing high bacterial densities and diverse ARGs that may spread through land application. Hydrothermal treatment (HT) is a process that inactivates pathogens and stabilizes biomass, but its performance at moderate temperatures is less understood. We evaluated HT (100°C–250°C; 2–24 h) for degrading bacterial DNA and ARGs in dewatered municipal sludge. DNA was quantified by fluorometry, bacterial presence confirmed by 16S rRNA gene PCR, and ARGs profiled by qPCR targeting 84 clinically and environmentally relevant genes. HT up to 250°C produced modest carbon densification, high solids …

Moderate-Temperature Hydrothermal Treatment Removes Detectable Dna And Antibiotic Resistance Genes From Municipal Sludge While Preserving Resource Value, R. Sean Norman, Mirza Isanovic, Gabrielle Kartzmark, Nicole Berge

Faculty Publications

Wastewater treatment plants (WWTPs) are key reservoirs of antibiotic resistance genes (ARGs), with municipal sludge containing high bacterial densities and diverse ARGs that may spread through land application. Hydrothermal treatment (HT) is a process that inactivates pathogens and stabilizes biomass, but its performance at moderate temperatures is less understood. We evaluated HT (100°C–250°C; 2–24 h) for degrading bacterial DNA and ARGs in dewatered municipal sludge. DNA was quantified by fluorometry, bacterial presence confirmed by 16S rRNA gene PCR, and ARGs profiled by qPCR targeting 84 clinically and environmentally relevant genes. HT up to 250°C produced modest carbon densification, high solids …

Characterizing Atmospheric Turbulence With The Lunar Step Response Method, Patrick D. Carattini, Caleb J. Stilp, Katelyn M. Atkinson, Stephen C. Cain

Faculty Publications

Most methods that astronomers use to characterize the strength of atmospheric turbulence in and around their observatories use differential image motion monitors observing a star to provide the necessary data for the measurement. With the Moon becoming a greater national priority, the need to characterize atmospheric paths between observatories on Earth and the Moon is potentially going to grow in the future. To this end, the differential image motion monitor is not an ideal instrument for characterizing turbulence along paths between observatories and the Moon as the bright Moon makes it difficult to detect and locate stars in its vicinity. …

Rural–Urban Differences In Cognitive Outcomes Among Older Adults: The Roles Of Falls And Depressive Symptoms, Ayse Malatyali, Tom Cidav, Lisa A.K. Wiese, Jian Zou, Monique J. Brown Ph.D., Mph, Junfeng Ma, Breno S. Diniz, Ladda Thiamwong

Faculty Publications

Background: Older adults with Alzheimer’s Disease and Related Dementias (ADRD) experience a higher risk of falls. However, research lacks evidence on the effect of fall exposure on cognitive impairment and dementia. We investigated the association of falls and depressive symptoms with cognitive impairment and dementia in a nationally representative sample. Methods: We analyzed data from 6221 participants (age ≥ 65) in the Health and Retirement Study (HRS) from the 2018–2020 waves, using Multinomial logistic regression models. Measures included the HRS health status questionnaire, HRS cognition scale, and the Center for Epidemiological Studies Depression scale. Results: Prevalence of fall exposure across …

Rural–Urban Differences In Cognitive Outcomes Among Older Adults: The Roles Of Falls And Depressive Symptoms, Ayse Malatyali, Tom Cidav, Lisa A.K. Wiese, Jian Zou, Monique J. Brown Ph.D., Mph, Junfeng Ma, Breno S. Diniz, Ladda Thiamwong

Faculty Publications

Background: Older adults with Alzheimer’s Disease and Related Dementias (ADRD) experience a higher risk of falls. However, research lacks evidence on the effect of fall exposure on cognitive impairment and dementia. We investigated the association of falls and depressive symptoms with cognitive impairment and dementia in a nationally representative sample. Methods: We analyzed data from 6221 participants (age ≥ 65) in the Health and Retirement Study (HRS) from the 2018–2020 waves, using Multinomial logistic regression models. Measures included the HRS health status questionnaire, HRS cognition scale, and the Center for Epidemiological Studies Depression scale. Results: Prevalence of fall exposure across …

Main-Chain Ion-Pair Polybenzimidazole Membranes Enabling Reduced-Temperature Ht-Pemfc Operation (Down To 120°C), Huina Lin, Brian C. Benicewicz

Faculty Publications

Proton exchange membrane (PEM) fuel cells are promising for clean and efficient energy conversion across diverse applications. High-temperature PEM fuel cells (HT-PEMFCs) using phosphoric acid (PA)-doped polybenzimidazole (PBI) can operate up to 200°C, but at lower temperatures, water-induced PA loss often leads to performance degradation and reduced durability. In this work, we present a new class of main-chain ion-pair PBI membranes by integrating the imidazolium-biphosphate ion-pair units directly into the PBI backbone. This design results in membranes with high acid content, stronger acid-polymer interactions and stabilized acid retention. In single-cell tests, the Im⁺-PBI15-3 wt.% exhibits peak power densities …

Generation Of Inner Core Anisotropy By Anisotropic Thermal Conductivity Of Iron Crystals, Prajna Paramita Das, Bruce Buffett, Daniel A. Frost

Faculty Publications

Seismic anisotropy in the Earth’s inner core refers to the observation that seismic waves travel faster along the Earth’s rotation axis than in the equatorial plane, a feature inferred from decades of global seismological observations. This directional dependence of wave speeds provides important clues about the structure, composition and dynamics of the inner core. Here we explore a coupled thermo-mechanical mechanism for the generation of inner core anisotropy, focusing on the effects of anisotropic thermal conductivity in iron crystals as the inner core cools. We propose that the higher thermal conductivity of iron along the crystallographic c-axis compared with …

Cognitive And Emotional Conflict Control Among Children Affected By Parental Hiv/Aids In China, Huihui Wang, Juan Liu, Danfeng Wen, Wan Zhao, Xiaoming Li Ph.D., Junfeng Zhao

Faculty Publications

Background: Children affected by parental HIV/AIDS constitute a particularly vulnerable population, often facing heightened risks in psychosocial adaptation due to family disruption, social stigma, and resource deprivation. However, the characteristics of their executive functions, particularly the core component of conflict monitoring, remain unclear.

Methods: The present study compared the performance of children affected by parental HIV/AIDS (n=32) to a control group (n=32) on a cognitive conflict and emotional conflict face-word Stroop task.

Results: The results of the cognitive Stroop task demonstrated that both groups showed better performance in congruent stimuli compared to incongruent stimuli (86.20% vs.67.30%; 568.43ms vs.586.04ms). In the …

Impediments To Transforming The Healthcare Delivery System: Shifting The Paradigm From Provider Centric To Patient Centric, Elizabeth A. Regan, Manasa Devi Chinta

Faculty Publications

Introduction: 

Stated aims for digital healthcare transformation frequently cite goals for better coordinated patient-centric systems. However, despite advances in medical science, digital technologies, health policies, and billions of dollars invested over the past 25 years, most healthcare providers are far from fully realizing the demonstrated benefits of today's digital technologies for improving patient care. Sharing information across healthcare systems remains challenging. Problems with fragmentation, quality, inequities, and rising costs of care delivery persist. A recent study of 1,026 U.S. hospital systems found that only 15.8 percent achieved a digital maturity level needed to provide digitally enabled healthcare services to better …

Hybrid Cnn–Gru-Based Demand–Supply Forecasting To Enhance Sustainability In Renewable-Integrated Smart Grids, Süleyman Emre Eyimaya, Necmi Altin

Faculty Publications

The rapid integration of renewable energy sources in smart grids has introduced significant uncertainty in both power generation and consumption patterns, posing challenges to environmental, economic, and operational sustainability. Accurate short-term forecasting of energy demand and supply is essential for achieving optimal scheduling, grid stability, and resilient operation in renewable-integrated power systems. This study proposes a hybrid deep learning framework combining Convolutional Neural Networks (CNN) and Gated Recurrent Units (GRU) for intelligent joint demand–supply forecasting in smart grids. The model was developed and implemented in MATLAB using real-world datasets comprising electricity consumption, photovoltaic (PV) generation, temperature, and irradiance variables. Comparative …

Influence Of Pulse Width On Energy Deposition And Temperature In Nanosecond-Pulsed Discharges, Christopher B. Reuter, Joshua B. Sinrud, Tanvir I. Farouk, Nicholas S. Dewey, Dmitri Kaganovich

Faculty Publications

Nanosecond-pulsed discharges are a promising method to enhance combustion but can generate significant levels of electromagnetic interference (EMI). Modifying the discharge pulse width is an unexplored option to reduce EMI, but few studies have examined how changing the pulse width affects discharge parameters such as energy and temperature. This study addresses this issue by systematically investigating how the pulse width affects the energy per pulse, breakdown time, rotational temperature, and vibrational temperature in air across different frequencies, flow velocities, and gap distances in a plasma-assisted flow tube. It is observed that the pulse width has a substantial impact on the …

Potential Impacts Of Climate Interventions On Marine Ecosystems, Kelsey E. Roberts, Tyler Rohr, Morgan R. Raven, Michael S. Diamond, Daniele Visioni, Ben Kravitz, Ryan Heneghan, Colleen M. Petrik, Daniele Bianchi, Kelly Ortega-Cisneros, Monica A. Morrison, Vanessa Van Heerden, Nicola A. Wiseman, Gouri Anil, Zachary J. Cannizzo, Marta Coll, Joshua Coupe, Ryan Freedman, Kristen Krumhardt, Lester Kwiatkowski, Nicole S. Lovenduski, Jessica Y. Luo, Holly C. Olivarez, Alan Robock, Jeroen Steenbeek, Cheryl S. Harrison

Faculty Publications

Rising global temperatures pose significant risks to marine ecosystems, biodiversity, and fisheries. Recent comprehensive assessments suggest that large-scale mitigation efforts to limit warming are falling short, and all feasible future climate projections, including those that represent optimistic emissions reductions, exceed the Paris Agreement's 1.5°C or 2° warming targets during this century. While avoiding further CO2 emissions remains the most effective way to prevent environmental destabilization, interest is growing in climate interventions—deliberate, large-scale manipulations of the environment aimed at reducing global warming. These include carbon dioxide removal (CDR) to reduce atmospheric CO2 concentrations over time, and solar radiation modification (SRM), which …

Complex Spin Structure In Co-Trimer-Chain Li2Co3Se4O12, Jie Xing, Feng Ye, Daniel Duong, Sai Mu, Max T. Pan, Rongying Jin

Faculty Publications

Complex magnetic materials are extremely attractive for revealing unconventional spin states and novel magnetic excitations. Here, we report the structural, thermodynamic, and magnetic properties of a novel magnetic material Li₂Co₃Se₄O₁₂based on x-ray and neutron diffraction, specific heat, magnetization, and x-ray photoelectron spectroscopy measurements. X-ray and neutron diffraction refinements reveal two Co sites Co (1) and Co (2) even though both are in the octahedral environment. While they are not connected along the b and c directions, these octahedra are edge-shared forming the Co (2) – Co (1) – Co (2) trimer chain …

Ecology And Life History Of Baleen Whales Inform Climate Change Vulnerabilities And Priorities For Future Monitoring, Lesley H. Thorne, Erin L. Meyer-Gutbrod

Faculty Publications

Baleen whales are key consumers in marine habitats that serve as vectors of nutrients, but their populations have been slow to recover from past commercial whaling due to their low reproductive rates and ongoing anthropogenic threats. Climate impacts have become central to the demography and habitat use of baleen whales, and conservation efforts must account for these impacts to be effective. However, knowledge of baleen whale climate responses is lacking, and current survey effort is insufficient to capture changes in migration and habitat use for many species. Due to their unique combination of ecological and life history characteristics, baleen whales …

Impact Of Suaahara, An Integrated Nutrition Programme, On Maternal And Child Nutrition At Scale In Nepal, Edward A. Frongillo Jr. Ph.D., Shalini Suresh, Deependra K. Thapa, Kenda Cunningham, Pooja Pandey Rana, Ramesh P. Adhikari, Subir Kole, Bhim Pun, Indra Kshetri, Debendra P. Adhikari, Rolf Klemm

Faculty Publications

Suaahara was an innovative, complex, multi-sectoral, large-scale, nutrition programme in Nepal to increase exposure to nutrition-related information and services, improve nutrition-related knowledge and practices among pregnant women and mothers of infants and young children, and improve their nutrition. This study evaluated the effectiveness of Suaahara to improve nutrition and nutrition-related practices by comparing changes over 10 years between intervention and comparison districts. The samples of households at baseline in 2012 and endline in 2022 were 2040 and 2480, respectively, from 120 old wards. The impact was estimated using intent-to-treat regression models in which survey year, arm and their interaction were …

Transfer Learning Neural Networks For Nuclear Forensic Image Morphology Using Image Splitting Techniques, Niko A. Petrocelli, Lee C. Lambert, Brett J. Borghetti, Abigail A. Bickley

Faculty Publications

Manual morphological analysis of actinide particles from scanning electron microscope (SEM) imagery is a critical component of nuclear forensics but is prone to significant inter-analyst variability. To address this challenge, this work develops and evaluates an automated classification method using deep learning. We introduce a methodology based on partitioning 1906 SEM images, representing 13 classes of uranium compounds, into smaller patches for analysis. Three convolutional neural network (CNN) architectures of increasing complexity were compared: a custom baseline CNN, a simple transfer learning model using ResNet50v1, and a complex model featuring hierarchical feature extraction and a spatial attention mechanism built upon …

Dynamic Magnetic Null Behavior In Planar Ion Diodes: Particle-In-Cell Analysis Of Field Oscillations And Ion Beam Dynamics, Jesse C. Foster, Stephen B. Swanekamp, Paul F. Ottinger

Faculty Publications

Particle-in-cell simulations of a 1.75 MV, 375 kA, and 50 ns planar pinched-beam diode reveal that the strongest gigahertz-frequency oscillations in electric field and ion current arise from the dynamic motion of the magnetic null near the anode tip. These oscillations, which appear when the ion transit time becomes comparable to the local field-variation timescale, periodically expand the effective anode–cathode gap and generate bursts of over-accelerated ions. The resulting ion energy spectrum broadens substantially near the null while maintaining excellent beam uniformity along the anode. The simulations, therefore, demonstrate a direct physical linkage between ion transit time instability and magnetic …