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Show Me! Do Videos Make A Difference In An Asynchronous Online Course?, John Griffith, Emily Faulconer Jul 2022

Show Me! Do Videos Make A Difference In An Asynchronous Online Course?, John Griffith, Emily Faulconer

Publications

This study attempted to determine if placing videos in an asynchronous course influenced the learning experience. Data were examined for an introductory college statistics course comparing results pre and post implementation of videos in support of discussions, assignments, homework, quizzes, and exams. Frequency of external tutoring was significantly reduced (40%) for the course sections that included embedded videos. This finding supports the idea that videos reduced the amount of friction or extraneous cognitive load experienced by students since using tutoring resources external to the course requires additional time and effort on the part of students and tutors. A significant majority …


Climatology Of Deep O+ Dropouts In The Night-Time F-Region In Solar Minimum Measured By A Langmuir Probe Onboard The International Space Station, Shantanab Debchoudhury, Aroh Barjatya, Joseh I. Minow, Victoria N. Coffey, Linda N. Parker Jul 2022

Climatology Of Deep O+ Dropouts In The Night-Time F-Region In Solar Minimum Measured By A Langmuir Probe Onboard The International Space Station, Shantanab Debchoudhury, Aroh Barjatya, Joseh I. Minow, Victoria N. Coffey, Linda N. Parker

Publications

The Floating Potential Measurement Unit (FPMU) onboard the International Space Station includes a Wide sweeping Langmuir Probe (WLP) that has been operating in the F-region of the ionosphere at ∼400 km since 2006. While traditional Langmuir probe estimates include critical plasma parameters like electron density and temperature, we have also extracted the O+ percentage from the total ion constituents. This O+ composition dataset from the recent minimum in the Solar Cycle 24 reveals orbits with dropouts in O+ to below 80% of the total background ion density at ISS orbital altitudes. The observed O+ percentages during these dropouts are much …


Career Advancement Of Women In Engineering Disciplines At Two-Year Degree Institutions: Documenting Challenges And Potential Solutions To Raise Inclusivity, Kimberly Luthi Jun 2022

Career Advancement Of Women In Engineering Disciplines At Two-Year Degree Institutions: Documenting Challenges And Potential Solutions To Raise Inclusivity, Kimberly Luthi

Publications

Institutions of higher education that offer two-year degrees have student-centered missions with support structures to address the unique needs of a diverse student body [14]. Many two-year degree institution types are open access and have institutional priorities focused on increasing diversity and inclusive practices among both the students and faculty [1]. Although the inclusion of women traditionally underrepresented in STEM disciplines in higher education settings is a national concern, the advancement of women at institutions that offer support networks and institutional practices such as two-year degree institutions contribute to women’s advancement and diversity in the talent pipeline. This research study …


Equity In Engineering Education: The Experiences Of Non-Traditional Students In Introductory Engineering Courses With Peer Learning Support, Kimberly T. Luthi, Mohua Kar Jun 2022

Equity In Engineering Education: The Experiences Of Non-Traditional Students In Introductory Engineering Courses With Peer Learning Support, Kimberly T. Luthi, Mohua Kar

Publications

This paper seeks to examine one aspect of the pilot research study entitled, “Engagement in Engineering Pathways: An Initiative to Retain Non-Traditional Students in Engineering” funded by the National Science Foundation Improving Undergraduate STEM Education grant program (Award No. 1712008). This three-year study examines the effect of the use of Peer-Led Team Learning (PLTL) on students’ academic performance, STEM experiences, and persistence in engineering programs [2]. The data collected is from May 2018- May 2020. The present study population is undergraduate engineering students at a multi-campus, federally designated Hispanic-serving, public, two-year college in the southeastern U.S. This paper will specifically …


Building Undergraduate Research In A Fully Online Engineering Program, Robert Deters, Brent Terwilliger, Emily Faulconer, Kelly A. George Jun 2022

Building Undergraduate Research In A Fully Online Engineering Program, Robert Deters, Brent Terwilliger, Emily Faulconer, Kelly A. George

Publications

This paper describes the creation and implementation of the support network of the Research Scholars Program at the Worldwide campus of Embry-Riddle Aeronautical University. Funded by an NSF IUSE grant, the purpose of this new program is to increase the opportunity for online engineering and engineering technology students to participate in undergraduate research. Studies have shown that participation in research can have an important impact on students, though online students are likely underrepresented in undergraduate research. The Research Scholars Program uses existing support systems of the campus while also building new components. These new components developed for this project are …


Modeling Studies Of Gravity Wave Dynamics In Highly Structured Environments: Reflection, Trapping, Instability, Momentum Transport, Secondary Gravity Waves, And Induced Flow Responses, Wenjun Dong, David C. Fritts, Michael P. Hickey, Alan Z. Liu, Thomas S. Lund, Shaodong Zhang, Yanying Yan, Fan Yang Jun 2022

Modeling Studies Of Gravity Wave Dynamics In Highly Structured Environments: Reflection, Trapping, Instability, Momentum Transport, Secondary Gravity Waves, And Induced Flow Responses, Wenjun Dong, David C. Fritts, Michael P. Hickey, Alan Z. Liu, Thomas S. Lund, Shaodong Zhang, Yanying Yan, Fan Yang

Publications

A compressible numerical model is applied for three-dimensional (3-D) gravity wave (GW) packets undergoing momentum deposition, self-acceleration (SA), breaking, and secondary GW (SGW) generation in the presence of highly-structured environments enabling thermal and/or Doppler ducts, such as a mesospheric inversion layer (MIL), tidal wind (TW), or combination of MIL and TW. Simulations reveal that ducts can strongly modulate GW dynamics. Responses modeled here include reflection, trapping, suppressed transmission, strong local instabilities, reduced SGW generations, higher altitude SGW responses, and induced large-scale flows. Instabilities that arise in ducts experience strong dissipation after they emerge, while trapped smaller-amplitude and smaller-scale GWs can …


Predicting The Impact Of Covid-19 On Air Transportation Volumes, Dothang Truong Jun 2022

Predicting The Impact Of Covid-19 On Air Transportation Volumes, Dothang Truong

Publications

COVID-19 has significant impacts on air transportation. This paper aims to predict domestic and international transportation volumes during the pandemic. Daily trips by distance are novel variables in the prediction. Additionally, COVID-19 severity, vaccination, and economic index are other predictors. Artificial Neural Networks and Monte Carlo simulations were used to develop and validate the predictive models using data from various sources in 2021. The findings confirm the importance of daily trips by distance and vaccination as significant predictors. Airlines can use the models to predict air transportation volumes and formulate appropriate strategies to meet the air travel demand and improve …


Numerical Implementation And Validation Of A Viscoelastic-Plastic Material Model For Predicting Curing Induced Residual Stresses In Adhesive Bonded Joints, Akshat Agha, Fadi Abu-Farha Jun 2022

Numerical Implementation And Validation Of A Viscoelastic-Plastic Material Model For Predicting Curing Induced Residual Stresses In Adhesive Bonded Joints, Akshat Agha, Fadi Abu-Farha

Publications

One of the main challenges in the joining of multi-material components is the assessment of the nature and magnitude of the residual stresses developing in the adhesive bond during the heat curing manufacturing process. Numerical modeling of these residual stresses can provide insights for making informed decisions related to (i) material substrate properties; (ii) adhesive properties i.e., low, medium, or high stiffness; (iii) bondline geometry i.e., bondline width and bead thickness; (iv) curing cycle characteristics; and (v) fixation design i.e., type, spacing, the number of joints. This work presents a cure history-dependent viscoelastic-plastic material description for the modeling of adhesive …


"A Conceptual Framework For Measuring Criminal Justice Success In Responding To Violence Against Women Act (Vawa) Crimes: Final Results And Recommendations", Sarah Goan, Kris Lugo-Graulich, Susy Hawes, Hannah Brintlinger Mph, Susan Smith Howley Jun 2022

"A Conceptual Framework For Measuring Criminal Justice Success In Responding To Violence Against Women Act (Vawa) Crimes: Final Results And Recommendations", Sarah Goan, Kris Lugo-Graulich, Susy Hawes, Hannah Brintlinger Mph, Susan Smith Howley

Publications

The Office on Violence Against Women (OVW), established under the Violence Against Women Act of 1994, leads national efforts to prevent and respond to domestic violence, dating violence, sexual assault, and stalking through 19 grant programs that strengthen victim services and enhance offender accountability. These programs include four formula grants distributed to states and fifteen discretionary programs for which OVW defines eligibility, goals, and deliverables. Grantees submit biannual progress reports containing quantitative and qualitative data that are later compiled into biennial Reports to Congress. While these reports effectively capture outputs such as numbers of victims served, trainings conducted, and partnerships …


Statistical Characteristics Of High-Frequency Gravity Waves Observed By An Airglow Imager At Andes Lidar Observatory, Alan Z. Liu, Bing Cao May 2022

Statistical Characteristics Of High-Frequency Gravity Waves Observed By An Airglow Imager At Andes Lidar Observatory, Alan Z. Liu, Bing Cao

Publications

The long-term statistical characteristics of high-frequency quasi-monochromatic gravity waves are presented using multi-year airglow images observed at Andes Lidar Observatory (ALO, 30.3° S, 70.7° W) in northern Chile. The distribution of primary gravity wave parameters including horizontal wavelength, vertical wavelength, intrinsic wave speed, and intrinsic wave period are obtained and are in the ranges of 20–30 km, 15–25 km, 50–100 m s−1, and 5–10 min, respectively. The duration of persistent gravity wave events captured by the imager approximately follows an exponential distribution with an average duration of 7–9 min. The waves tend to propagate against the local background winds and …


Deconstructing Tiktok Videos On Mental Health: Cross-Sectional, Descriptive Content Analysis, Corey H. Basch, Lorie Donelle Phd, Rn, Fcan, Joseph Fera, Christie Jaime May 2022

Deconstructing Tiktok Videos On Mental Health: Cross-Sectional, Descriptive Content Analysis, Corey H. Basch, Lorie Donelle Phd, Rn, Fcan, Joseph Fera, Christie Jaime

Publications

BACKGROUND: Social media platforms that are based on the creation of visual media, such as TikTok, are increasingly popular with adolescents. Online social media networks provide valuable opportunities to connect with each other to share experiences and strategies for health and wellness. OBJECTIVE: The aim of this study was to describe the content of the hashtag #mentalhealth on TikTok. METHODS: This cross-sectional, descriptive content analysis study included 100 videos with the hashtag #mentalhealth on TikTok. All videos that included the hashtag #mentalhealth were analyzed and coded for the presence of content categories. Additionally, the comments to each video were viewed …


Mesosphere And Lower Thermosphere Changes Associated With The 2 July 2019 Total Eclipse In South America Over The Andes Lidar Observatory, Cerro Pachon, Chile, A. Liu, F. Vargas, G. Swenson, C. Segura, P. Vega, J. Fuentes, D. Pautet, M. Taylor, Y. Zhao, Y. Morton, H. Bourne May 2022

Mesosphere And Lower Thermosphere Changes Associated With The 2 July 2019 Total Eclipse In South America Over The Andes Lidar Observatory, Cerro Pachon, Chile, A. Liu, F. Vargas, G. Swenson, C. Segura, P. Vega, J. Fuentes, D. Pautet, M. Taylor, Y. Zhao, Y. Morton, H. Bourne

Publications

This article presents the results of a week of observations around the 2 July 2019, total Chilean eclipse. The eclipse occurred between 19:22 and 21:46 UTC, with complete sun disc obscuration at 20:38–20:40 UTC (16:38–16:40 LT) over the Andes Lidar Observatory (ALO) at (30.3°S, 70.7°W). Observations were carried out using ALO instrumentation with the goal to observe possible eclipse-induced effects on the mesosphere and lower thermosphere region (MLT; 75–105 km altitude). To complement our data set, we have also utilized TIMED/SABER temperatures and ionosonde electron density measurements taken at the University of La Serena's Juan Soldado Observatory. Observed events include …


Student Understanding Of Kinematics: A Qualitative Assessment, Andrew Cashman, Tom O'Mahony May 2022

Student Understanding Of Kinematics: A Qualitative Assessment, Andrew Cashman, Tom O'Mahony

Publications

In engineering, kinematics is widely regarded as a fundamental topic with the literature agreeing that students possess a wide range in understanding of the topic. This study aims to take a second-order approach by understanding and exploring the qualitatively different ways in which students approach solving kinematics problems. Phenomenography was used to collect data through ten semi-structured interviews with early-stage mechanical engineering students. Following data analysis, four distinct categories of students’ approaches were identified; unstructured, framing the problem, strategic, and conceptual. It was found that these categories could be arranged in a hierarchy and were also supported by secondary epistemic …


Insights From The Field: Project Execution Success And Failure, Tracey M. Richardson, James W. Marion Jr, Vittal S. Anantatmula, James R. Gibson May 2022

Insights From The Field: Project Execution Success And Failure, Tracey M. Richardson, James W. Marion Jr, Vittal S. Anantatmula, James R. Gibson

Publications

Project execution plays a decisive role in project success, but past research did not focus on the project manager’s perspective of what needs to be accomplished to achieve success. In this study, the authors used qualitative techniques to look for reoccurring themes related to 44project managers’ responses to interview questions associated with successful project execution and failed project execution. The study found that despite the project management profession growth, professional associations’ efforts, and their professional development endeavors, project management execution seems to be concerned with what has happened versus what is happening in a project. This study provides a conceptual …


Mapping And Making Meaning From Undergraduate Student Engagement In High-Impact Educational Practices, Bridget G. Trogden, Cazembe Kennedy, Nathan K. Biyani May 2022

Mapping And Making Meaning From Undergraduate Student Engagement In High-Impact Educational Practices, Bridget G. Trogden, Cazembe Kennedy, Nathan K. Biyani

Publications

Institutions of higher education often have multiple entry points for first-time and transfer college students to engage in high-impact educational practices (HIPs), well documented to advance student learning outcomes. Some students may seek out repeated opportunities while others engage very little or not at all in activities such as student-faculty research, study abroad, internships, first-year cohort programs, service-learning, and the like. When institutions maintain decentralized data and records on students’ participation, obtaining a true understanding of the "who, what, when, and where" of HIPs can be difficult. In this paper, we present an institutional strategy for longitudinal collection of data …


A Monte Carlo Method For Evaluating Empirical Gyrochronology Models And Its Application To Wide Binary Benchmarks, Tomomi Otani, Ted Von Hippel, Derek Buzasi, Terry Oswalt, Alexander Stone-Martinez, Patrice Majewski May 2022

A Monte Carlo Method For Evaluating Empirical Gyrochronology Models And Its Application To Wide Binary Benchmarks, Tomomi Otani, Ted Von Hippel, Derek Buzasi, Terry Oswalt, Alexander Stone-Martinez, Patrice Majewski

Publications

No abstract provided.


Numeric Forced Rank: A Lightweight Method For Comparison And Decision-Making, Erin Gannon, Barbara Chaparro Apr 2022

Numeric Forced Rank: A Lightweight Method For Comparison And Decision-Making, Erin Gannon, Barbara Chaparro

Publications

Comparing products, features, brands, or ideas relative to one another is a common goal in user experience (UX) and market research. While Likert-type scales and ordinal stack ranks are often employed as prioritization methods, they are subject to several psychometric shortcomings. We introduce the numeric forced rank, a lightweight approach that overcomes some of the limitations of standard methods and allows researchers to collect absolute ratings, relative preferences, and subjective comments using a single scale. The approach is optimal for UX and market research, but is also easily employed as a structured decision-making exercise outside of consumer research. We describe …


Challenges In Kinetic-Kinematic Driven Musculoskeletal Subject-Specific Infant Modeling, Yeram Lim, Victor Huayamave, Tamara Chambers, Christine Walck, Safeer Siddicky, Erin Mannen Apr 2022

Challenges In Kinetic-Kinematic Driven Musculoskeletal Subject-Specific Infant Modeling, Yeram Lim, Victor Huayamave, Tamara Chambers, Christine Walck, Safeer Siddicky, Erin Mannen

Publications

Musculoskeletal computational models provide a non-invasive approach to investigate human movement biomechanics. These models could be particularly useful for pediatric applications where in vivo and in vitro biomechanical parameters are difficult or impossible to examine using physical experiments alone. The objective was to develop a novel musculoskeletal subject-specific infant model to investigate hip joint biomechanics during cyclic leg movements. Experimental motion-capture marker data of a supine-lying 2-month-old infant were placed on a generic GAIT 2392 OpenSim model. After scaling the model using body segment anthropometric measurements and joint center locations, inverse kinematics and dynamics were used to estimate hip ranges …


The Replacement Rule For Nonlinear Shallow Water Waves, A. Ludu, Z. Zong Apr 2022

The Replacement Rule For Nonlinear Shallow Water Waves, A. Ludu, Z. Zong

Publications

When a (1 + 1)-dimensional nonlinear PDE in real function η(x, t) admits localized traveling solutions we can consider L to be the average width of the envelope, A the average value of the amplitude of the envelope, and V the group velocity of such a solution. The replacement rule (RR or nonlinear dispersion relation) procedure is able to provide a simple qualitative relation between these three parameters, without actually solve the equation. Examples are provided from KdV, C-H and BBM equations, but the procedure appears to be almost universally valid for such (1 + 1)-dimensional nonlinear PDE and their …


Retention Of Qualified Cybersecurity Professionals: A Qualitative Study, Andrew Ishmael, Leila Halawi Apr 2022

Retention Of Qualified Cybersecurity Professionals: A Qualitative Study, Andrew Ishmael, Leila Halawi

Publications

The current endeavors to retain cybersecurity professionals are not enough to sustain the needs of the U.S. workforce. The researchers aim to explore retention strategies for qualified cybersecurity professionals supporting U.S. government contracts at a leading global security company. The researchers interviewed a sample of qualified cybersecurity professionals supporting U.S. government contracts to get essential information on retention in the cybersecurity profession. The researchers proposed four distinct pillars to make up the strategic framework for retaining qualified cybersecurity professionals.


Improving White Dwarfs As Chronometers With Gaia Parallaxes And Spectroscopic Metallicities, Adam Moss, Ted Von Hippel, Elliot Robinson, Kareem El-Badry, David C. Stenning, David Van Dyk, Morgan Fouesneau, Coryn A.L. Bailer-Jones, Elizabeth Jeffery, Jimmy Sargent, Isabelle Kloc, Natalie Moticska Apr 2022

Improving White Dwarfs As Chronometers With Gaia Parallaxes And Spectroscopic Metallicities, Adam Moss, Ted Von Hippel, Elliot Robinson, Kareem El-Badry, David C. Stenning, David Van Dyk, Morgan Fouesneau, Coryn A.L. Bailer-Jones, Elizabeth Jeffery, Jimmy Sargent, Isabelle Kloc, Natalie Moticska

Publications

White dwarfs (WDs) offer unrealized potential in solving two problems in astrophysics: stellar age accuracy and precision. WD cooling ages can be inferred from surface temperatures and radii, which can be constrained with precision by high-quality photometry and parallaxes. Accurate and precise Gaia parallaxes along with photometric surveys provide information to derive cooling and total ages for vast numbers of WDs. Here we analyze 1372 WDs found in wide binaries with main-sequence (MS) companions and report on the cooling and total age precision attainable in these WD+MS systems. The total age of a WD can be further constrained if its …


Using Small Uas For Stem Education: Introducing Robotics And Mechatronics With Drones, Christian Janke, Kimberly Luthi, Stefan Kleinke, Yuetong Lin Apr 2022

Using Small Uas For Stem Education: Introducing Robotics And Mechatronics With Drones, Christian Janke, Kimberly Luthi, Stefan Kleinke, Yuetong Lin

Publications

Several global developments point to importance of STEM-related education and studies. Every industry sector faces challenges in the recruiting of qualified personnel, due to retiring employees and general economic growth. Also, several domains, foremost automotive and aviation are undergoing a tremendous shift towards electrification to achieve sustainability. Hence, sparking the interest in STEM studies, education and vocational training cannot start early enough. This paper introduces the benefits of the educational use of sUAS by identifying core benefits in the three domains of learning – cognitive, affective, psycho-motor. Preliminary data and survey results from from several science, technology, engineering and math …


Service-Learning In Undergraduate General Chemistry: A Review, Emily Faulconer, C. J. Y. Kam Apr 2022

Service-Learning In Undergraduate General Chemistry: A Review, Emily Faulconer, C. J. Y. Kam

Publications

Background: Service-learning is gaining recognition as a valuable pedagogy for students to gain both academic and psychosocial benefits. This high-impact practice allows students to achieve course learning objectives while contributing to their community's needs. A review from 2007 revealed a lack of research focused on the topic in the prior decade, despite the interest that was shown by the American Chemical Society in 2000. Purpose: This review of recent case studies on the topic provides future researchers and practitioners with an understanding of the current state of service-learning in undergraduate chemistry courses. Methodology/Approach: To create a representative sample of recent …


Dataset On Student Experiences And Perceptions Of Emergency Remote Teaching (Ert) In An Irish University, Gearóid Ó' Súilleabháin, Tom Farrelly, Seán Lacey Apr 2022

Dataset On Student Experiences And Perceptions Of Emergency Remote Teaching (Ert) In An Irish University, Gearóid Ó' Súilleabháin, Tom Farrelly, Seán Lacey

Publications

This paper presents a dataset from a survey of student experiences and perceptions of Emergency Remote Teaching (ERT) during the COVID-19 pandemic in the Munster Technological University, a new higher education institute in the south-west of Ireland formed from the recent merger of two older institutes of technology. Data were collected throughout the month of May 2021 using the online survey tool Typeform with the survey itself being promoted with the student body primarily via email, social media and the university's Learning Management System. There were a total of 1703 responses (approx. 11% response rate which maps to less than …


Discovery Of Quasi-Periodic Oscillations In The Persistent X-Ray Emission Of Accreting Binary X-Ray Pulsar Lmc X-4, Ketan Rikame, Biswajit Paul, Pragati Pradhan, K.T. Paul Mar 2022

Discovery Of Quasi-Periodic Oscillations In The Persistent X-Ray Emission Of Accreting Binary X-Ray Pulsar Lmc X-4, Ketan Rikame, Biswajit Paul, Pragati Pradhan, K.T. Paul

Publications

We report the discovery of quasi-periodic oscillations (QPOs) in the high-mass X-ray binary (HMXB) pulsar LMC X-4 in its non-flaring (persistent) state using observations with XMM–Newton. In addition to the 74 mHz coherent pulsations, the persistent emission light curve shows a QPO feature in the frequency range of 20–30 mHz. Quasi-periodic flares have been previously observed from LMC X-4 in observations made with Rossi X-ray Timing Explorer (RXTE). However, this is the first time QPOs have been observed in the persistent emission observations of LMC X-4. QPOs in X-ray binaries are generally thought to be related to the rotation of …


Using Machine Learning In Estimating Changing Bed Shear Over A Flume Test Box, Ghada S. Ellithy, Siddharth S. Parida Mar 2022

Using Machine Learning In Estimating Changing Bed Shear Over A Flume Test Box, Ghada S. Ellithy, Siddharth S. Parida

Publications

A dam or levee breach caused by overflow erosion is difficult to evaluate during an overtopping event due to difficulty in accessibility and quickly changing conditions. However, for assessment of risk associated with breach time and ensuing downstream consequences, the erosion rate of embankment soils during this process needs to be evaluated. Soil erosion and water depth measurements were taken during flume tests using a Shallow Water Lidar (SWL) system scans. The tests were conducted in a 1-m-wide tilting flume on three cleans and gravel soil mixes with a median grain size D50of 2, 5,and 20 mm. The box measured …


Accreting On The Edge: A Luminosity-Dependent Cyclotron Line In The Be/X-Ray Binary 2s 1553-542 Accompanied By Accretion Regimes Transition, C. Malacaria, Y. Bhargava, Joel B. Coley, L. Ducci, Pragati Pradhan, R. Ballhausen, F. Fuerst, N. Islam, G. K. Jaisawal, P. Jenke, P. Kretschmar, I. Kreykenbohm, K. Pottschmidt, E. Sokolova-Lapa, R. Staubert, J. Wilms, C.A. Wilson-Hodge, Michael T. Wolff Mar 2022

Accreting On The Edge: A Luminosity-Dependent Cyclotron Line In The Be/X-Ray Binary 2s 1553-542 Accompanied By Accretion Regimes Transition, C. Malacaria, Y. Bhargava, Joel B. Coley, L. Ducci, Pragati Pradhan, R. Ballhausen, F. Fuerst, N. Islam, G. K. Jaisawal, P. Jenke, P. Kretschmar, I. Kreykenbohm, K. Pottschmidt, E. Sokolova-Lapa, R. Staubert, J. Wilms, C.A. Wilson-Hodge, Michael T. Wolff

Publications

Accreting X-ray pulsars undergo luminous X-ray outbursts during which the luminosity-dependent spectral and timing features of the neutron star’s emission can be analyzed in detail, thus shedding light on the accretion regime at work. We took advantage of a monitoring campaign that was performed with NuSTAR, Swift/XRT, AstroSat and NICER to follow the Be/X-ray Binary 2S 1553-542 along one of its rare outbursts, and thus trace its spectral and timing evolution. We report the discovery of a luminosity-dependent cyclotron line energy for the first time in this source. The pulse profiles and pulsed fraction also show variability along the outburst, …


Oxygen Ion Escape At Venus Associated With Three-Dimensional Kelvin-Helmholtz Instability, Tong Dang, Xuanye Ma, Jiuhou Le, Binzheng Zhang, Tielong Zhang, Zhonghua Yao, John Lyon, Sudong Xiao, Maodong Yan, Oliver Brambles, Kareem Sorathia Mar 2022

Oxygen Ion Escape At Venus Associated With Three-Dimensional Kelvin-Helmholtz Instability, Tong Dang, Xuanye Ma, Jiuhou Le, Binzheng Zhang, Tielong Zhang, Zhonghua Yao, John Lyon, Sudong Xiao, Maodong Yan, Oliver Brambles, Kareem Sorathia

Publications

How oxygens escape from Venus has long been a fundamental but controversial topic in the planetary research. Among various key mechanisms, the Kelvin-Helmholtz instability (KHI) has been suggested to play an important role in the oxygen ion escape from Venus. Limited by either scarce in-situ observations or simplified theoretical estimations, the mystery of oxygen ion escape process associated with KHI is still unsettled. Here we present the first three-dimensional configuration of KHI at Venus with a global multifluid magnetohydrodynamics model, showing a significantly fine structure and evolution of the KHI. KHI mainly occurred at the low latitude boundary layer if …


Remote Elementary Education (Part 2): Grade-Level Comparative Analysis With Control, Stefan Kleinke, David Cross Mar 2022

Remote Elementary Education (Part 2): Grade-Level Comparative Analysis With Control, Stefan Kleinke, David Cross

Publications

Purpose – The purpose of this two-part research was to investigate the effect of remote learning on student progress in elementary education. Part 2, presented in this paper, is a follow-up study to examine how student progression in the two pandemic-induced environments compared to the pre-pandemic conditions. Design/methodology/approach – The authors expanded the quantitative, quasi-experimental factorial design of the authors’ initial study with additional ex-post-facto standardized test score data from before the pandemic to enhance the group comparison with a control: the conventional pre-pandemic classroom environment. Thus, the authors were able to examine in which ways the two pandemic-induced learning …


Simulation Of Infrasonic Acoustic Wave Imprints On Airglow Layers During The 2016 M7.8 Kaikoura Earthquake, P. A. Inchin, J. Aguilar Guerrero, J. B. Snively, Y. Kaneko Mar 2022

Simulation Of Infrasonic Acoustic Wave Imprints On Airglow Layers During The 2016 M7.8 Kaikoura Earthquake, P. A. Inchin, J. Aguilar Guerrero, J. B. Snively, Y. Kaneko

Publications

Simulations of hypothesized but unobserved mesopause airglow (MA) disturbances generated by infrasonic acoustic waves (IAWs) during the 2016 M7.8 Kaikoura earthquake are performed. Realistic surface displacements are calculated in a forward seismic wave propagation model and incorporated into a 3-D nonlinear compressible neutral atmosphere model as a source of IAWs at the surface-air interface. Inchin et al. (2021), https://doi.org/10.1029/2020av000260 previously showed that Global Positioning System-based total electron content (TEC) observations can be used to constrain the finite-fault kinematics of the Kaikoura earthquake. However, due to limitations of Global Navigation Satellite System network coverage and coalescence of nonlinear IAW fronts, they …