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Articles 121 - 150 of 1382
Full-Text Articles in Physical Sciences and Mathematics
Rethinking Integrated Computer Science Instruction: A Cross-Context And Expansive Approach In Elementary Classrooms, Umar Shehzad, Jody E. Clarke-Midura, Kimberly Beck, Jessica F. Shumway, Mimi M. Recker
Rethinking Integrated Computer Science Instruction: A Cross-Context And Expansive Approach In Elementary Classrooms, Umar Shehzad, Jody E. Clarke-Midura, Kimberly Beck, Jessica F. Shumway, Mimi M. Recker
Publications
This study examines how a rural-serving school district aimed to provide elementary level computer science (CS) by offering instruction during students’ computer lab, a class taught by paraprofessional educators with limited background in computing. As part of a research practice partnership, cross-context mathematics and CS lessons were co-designed to expansively frame and highlight connections across – as opposed to integration within – the two subjects. Findings indicate that the paraprofessionals teaching the lessons generally reported positive experiences and understanding of content; however, those less comfortable with the content reported lower student interest. Further, most students who engaged with the lessons …
Differences In Pathogenesis-Related Protein Expression And Polyphenolic Compound Accumulation Reveal Insights Into Tomato-Pythium Aphanidermatum Interaction, Seham A. Soliman, Abdulaziz A. Al-Askar, Sherien Sobhy, Marwa A. Samy, Esraa Hamdy, Omaima A. Sharaf, Yiming Su, Said I. Behiry, Ahmed Abdelkhalek
Differences In Pathogenesis-Related Protein Expression And Polyphenolic Compound Accumulation Reveal Insights Into Tomato-Pythium Aphanidermatum Interaction, Seham A. Soliman, Abdulaziz A. Al-Askar, Sherien Sobhy, Marwa A. Samy, Esraa Hamdy, Omaima A. Sharaf, Yiming Su, Said I. Behiry, Ahmed Abdelkhalek
Publications
Plant diseases significantly reduce crop yields, threatening food security and agricultural sustainability. Fungi are the most destructive type of phytopathogen, and they are responsible for major yield losses in some of the most crucial crops grown across the world. In this study, a fungus isolate was detected from infected tomato plants and molecularly identified as Pythium aphanidermatum (GenBank accession number MW725032). This fungus caused damping-off disease and was shown to be pathogenic. Moreover, the expression of five pathogenesis-related genes, namely PR-1, PR-2, PR-3, PR-4, and PR-5, was quantitatively evaluated under the inoculation of tomato with …
Gravity Waves Emitted From Kelvin-Helmholtz Instabilities, Alan Z. Liu, Wenjun Dong, David C. Fritts, Thomas S. Lunda, Han-Li Liu
Gravity Waves Emitted From Kelvin-Helmholtz Instabilities, Alan Z. Liu, Wenjun Dong, David C. Fritts, Thomas S. Lunda, Han-Li Liu
Publications
Fritts, Wang, Lund, and Thorpe (2022, https://doi.org/10.1017/jfm.2021.1085) and Fritts, Wang, Thorpe, and Lund (2022, https://doi.org/10.1017/jfm.2021.1086) described a 3-dimensional direct numerical simulation of interacting Kelvin-Helmholtz instability (KHI) billows and resulting tube and knot (T&K) dynamics that arise at a stratified shear layer defined by an idealized, large-amplitude inertia-gravity wave. Using similar initial conditions, we performed a high-resolution compressible simulation to explore the emission of GWs by these dynamics. The simulation confirms that such shear can induce strong KHI with large horizontal scales and billow depths that readily emit GWs having high frequencies, small horizontal wavelengths, and large vertical group velocities. The …
Sustainable Atos - Flying To Net Zero, Eva Maleviti, Bettina Mrusek
Sustainable Atos - Flying To Net Zero, Eva Maleviti, Bettina Mrusek
Publications
Pathways to Net Zero- Targets
Improve fuel-efficiency by an average of 2% per year - 2020 to 2030
Reduction in total carbon dioxide emissions to net-zero by 2050.
After 2026 carbon allowances will be zero for EU.
An Exploration Of Computational Text Analysis Of Co-Design Discourse In A Research-Practice Partnership, Mei Tan, Victor R. Lee
An Exploration Of Computational Text Analysis Of Co-Design Discourse In A Research-Practice Partnership, Mei Tan, Victor R. Lee
Publications
In combination with contextualized human interpretation, computational text analysis offers a quantitative approach to interrogating the nature of participation and social positioning in discourse. Using meeting transcript data from the development of a co-design research-practice partnership, we examine the roles and forms of participation that contribute to an effective collaboration between a multileveled school system and researcher partners. We apply computational methods to explore the language of co-design and multi-stakeholder perspectives in support of educational improvement science efforts and our theoretical understanding of partnership roles. Results indicate participation patterns align with documented roles in co- design partnerships and highlight the …
Geometry And Coding: Introducing An Interactive And Integrated Mathematics-Computer Science Unit, Kimberly Beck, Jessica F. Shumway
Geometry And Coding: Introducing An Interactive And Integrated Mathematics-Computer Science Unit, Kimberly Beck, Jessica F. Shumway
Publications
As part of a collaborative project between Utah State University, the Cache County School District, and Stanford, instructional units were designed for fifth-grade students. These units integrated math concepts of geometrical shapes and computer science concepts of sequences, conditionals, and loops. One component of the unit was implemented in math classrooms by math teachers, and the other component was implemented in computer labs. This presentation will focus on the math unit as presented at the National Council of Teachers of Mathematics (NCTM-V).
Analysis Of Energy Transfer Among Background Flow, Gravity Waves And Turbulence In The Mesopause Region In The Process Of Gravity Wave Breaking From A High-Resolution Atmospheric Model, Fan Yang, Alan Z. Liu, Christopher J. Heale, Jonathan B. Snively, Wenjun Dong, Thomas Lund
Analysis Of Energy Transfer Among Background Flow, Gravity Waves And Turbulence In The Mesopause Region In The Process Of Gravity Wave Breaking From A High-Resolution Atmospheric Model, Fan Yang, Alan Z. Liu, Christopher J. Heale, Jonathan B. Snively, Wenjun Dong, Thomas Lund
Publications
We conducted an analysis of the process of GW breaking from an energy perspective using the output from a high-resolution compressible atmospheric model. The investigation focused on the energy conversion and transfer that occur during the GW breaking. The total change in kinetic energy and the amount of energy converted to internal energy and potential energy within a selected region were calculated. Prior to GW breaking, part of the potential energy is converted into kinetic energy, most of which is transported out of the chosen region. After the GW breaks and turbulence develops, part of the potential energy is converted …
Analysis Of Energy Transfer Among Background Flow, Gravity Waves And Turbulence In The Mesopause Region In The Process Of Gravity Wave Breaking From A High-Resolution Atmospheric Model, Alan Z. Liu, Fan Yang, Christopher James Heale, Jonathan Brian Snively, Wenjun Dong, Thomas Lund
Analysis Of Energy Transfer Among Background Flow, Gravity Waves And Turbulence In The Mesopause Region In The Process Of Gravity Wave Breaking From A High-Resolution Atmospheric Model, Alan Z. Liu, Fan Yang, Christopher James Heale, Jonathan Brian Snively, Wenjun Dong, Thomas Lund
Publications
We conducted an analysis of the process of GW breaking from an energy perspective using the output from a high-resolution compressible atmospheric model. The investigation focused on the energy conversion and transfer that occur during the GW breaking. The total change in kinetic energy and the amount of energy converted to internal energy and potential energy within a selected region were calculated.
Prior to GW breaking, part of the potential energy is converted into kinetic energy, most of which is transported out of the chosen region. After the GW breaks and turbulence develops, part of the potential energy is converted …
The U.S. Integrated Ocean Observing System (Ioos): A Prototype User Valuation, Charles S. Colgan, Castelletto Anthony
The U.S. Integrated Ocean Observing System (Ioos): A Prototype User Valuation, Charles S. Colgan, Castelletto Anthony
Publications
The Integrated Ocean Observing System of the United States provides a large variety of oceanographic and related data at no charge through 11 Regional Associations. Since the data is distributed without price it is difficult to determine the economic value of the data. That value is useful in explaining and justifying the investment in ocean observing. This study applies discrete choice modeling to determine valuation of the data for users of data through the RA websites. The study found annual values of $190 to $220 million, and these estimates are considered highly conservative. A guide for replication of the valuation …
Clumpy Wind Studies And The Nondetection Of A Cyclotron Line In Oao 1657–415, Pragati Pradhan, Carlo Ferrigno, Biswajit Paul, Enrico Bozzo, Ileyk El Mellah, David P. Huenemoerder, James F. Steiner, Victoria Grinberg, Felix Furst, Chandreyee Maitra, Patrizia Romano, Peter Kretschmar, Jamie Kennea, Deepto Chakrabarty
Clumpy Wind Studies And The Nondetection Of A Cyclotron Line In Oao 1657–415, Pragati Pradhan, Carlo Ferrigno, Biswajit Paul, Enrico Bozzo, Ileyk El Mellah, David P. Huenemoerder, James F. Steiner, Victoria Grinberg, Felix Furst, Chandreyee Maitra, Patrizia Romano, Peter Kretschmar, Jamie Kennea, Deepto Chakrabarty
Publications
Winds of massive stars are suspected to be inhomogeneous (or clumpy), which biases the measures of their mass-loss rates. In high-mass X-ray binaries (HMXBs), the compact object can be used as an orbiting X-ray point source to probe the wind and constrain its clumpiness. We perform a spectrotiming analysis of the HMXB OAO 1657–415 with nonsimultaneous NuSTAR and NICER observations. We compute the hardness ratio from the energy-resolved light curves, and, using an adaptive rebinning technique, we thus select appropriate time segments to search for rapid spectral variations on timescales of a few hundred to thousands of seconds. The column …
Periodicities And Plasma Density Structure Of Jupiter’S Dawnside Magnetosphere, Xuanye Ma, A.A. Schok, P.A. Delamere, B. Mino, P.A. Damiano, B. Zhang, A. Sciola
Periodicities And Plasma Density Structure Of Jupiter’S Dawnside Magnetosphere, Xuanye Ma, A.A. Schok, P.A. Delamere, B. Mino, P.A. Damiano, B. Zhang, A. Sciola
Publications
The ability to quantify variations in magnetic field topology and density within Jupiter’s magnetosphere is an important step in understanding the overall structure and dynamics. The Juno spacecraft has provided a rich data set in the dawnside magnetosphere. The recent Grid Agnostic MHD for Extended Research Applications (GAMERA) global simulation study by Zhang et al. (2021) showed a highly structured plasmadisc with closed magnetic field lines mapping between the outer dawn-tail flank and the high latitude polar region. To test these model predictions, we examined Juno’s magnetic field data and electron/energetic particle data to categorize portions of orbits 1-15 into …
Gravity Wave Drag Parameterizations For Earth’S Atmosphere, Christopher J. Heale, Christopher G. Kruse, Jadwiga H. Richter, M. Joan Alexander, Julio T. Bacmeister, Junhong Wei
Gravity Wave Drag Parameterizations For Earth’S Atmosphere, Christopher J. Heale, Christopher G. Kruse, Jadwiga H. Richter, M. Joan Alexander, Julio T. Bacmeister, Junhong Wei
Publications
Atmospheric gravity waves (GWs), or buoyancy waves, transport momentum and energy through Earth’s atmosphere. GWs are important at nearly all levels of the atmosphere, though, the momentum they transport is particularly important in general circulation of the middle and upper atmosphere. Primary sources of atmospheric GWs are flow over mountains, moist convection, and imbalances in jet/frontal systems. Secondary GWs can also be generated as a result of dissipation of a primary GWs. Gravity waves typically have horizontal wavelengths of 10’s to 100’s of kilometers, though, they can have scales of 1’s to 1000’s of kilometers as well. Current effective resolutions …
Chesapeake Bay Watershed Residents’ And Farmers’ Concerns And Perceptions Of Water Quality, Edem Avemegah, Jessica D. Ulrich-Schad
Chesapeake Bay Watershed Residents’ And Farmers’ Concerns And Perceptions Of Water Quality, Edem Avemegah, Jessica D. Ulrich-Schad
Publications
Poor water quality is an issue in the Chesapeake Bay Watershed (CBW). In this rapidly urbanizing landscape, both farmers and non-farm residents contribute to nutrient pollution of rivers and streams. Understanding these important stakeholders’ views of water quality problems and how to address them is essential for creating an economically thriving and environmentally beneficial agricultural system that all residents depend upon. To understand key stakeholders’ views on water quality both locally and regionally, researchers from Utah State University and the Pennsylvania State University surveyed residents of the CBW and agricultural producers of the southern part of the CBW (Maryland, Delaware, …
Chesapeake Bay Watershed Residents’ And Farmers’ Views On Urban And Suburban Growth, Edem Avemegah, Jessica D. Ulrich-Schad
Chesapeake Bay Watershed Residents’ And Farmers’ Views On Urban And Suburban Growth, Edem Avemegah, Jessica D. Ulrich-Schad
Publications
What the future of agriculture in the Chesapeake Bay Watershed (CBW) will look like is uncertain due to issues such as the loss of farmland to sprawling suburban development. In this rapidly urbanizing landscape, tension can also arise between farmers and their non-farm neighbors due to their proximity to each other. Understanding the concerns of these stakeholders regarding the urban and suburban growth and the potential problems that are likely to occur with farmers being in close contact with their non-farm neighbors is a good step in ensuring an economically thriving and environmentally beneficial agricultural system that all residents depend …
Red Wolf Multispecies Justice Publication 2023, Eskar, Elizabeth Bennett, Finley Schad, Alex Baldwin, Oluwaseyifunmi Adejugbe, Mufti Nadimul Quamar Ahmed, Maisie Schad, Sadie Braddock, Azra Soyer, Melih Soyer, Anne-Laure Blanche, Zubair Barkat, Amol K, Sarah Ann Woodbury, Kirsten Vinyeta
Red Wolf Multispecies Justice Publication 2023, Eskar, Elizabeth Bennett, Finley Schad, Alex Baldwin, Oluwaseyifunmi Adejugbe, Mufti Nadimul Quamar Ahmed, Maisie Schad, Sadie Braddock, Azra Soyer, Melih Soyer, Anne-Laure Blanche, Zubair Barkat, Amol K, Sarah Ann Woodbury, Kirsten Vinyeta
Publications
Our understanding of multispecies justice is still solidifying. In spring 2023, a group of Utah State University undergraduate and graduate students attended a course by Dr.Kirsten Vinyeta on Multispecies Justice and Indigenous Approaches to the Environment. Throughout this course, we studied the works of scholars and writers from a variety of social locations and identities who challenge Western theoretical frameworks in social science.
This publication celebrates our intellectual struggle with this emerging field and opens a forum for conversations about justice for humans and additional species. This issue features various writings, reflections, and photos from students taking the Multispecies Justice …
Air Traffic Management Principles: A Case Study On How To Create A Sustainable System, Eva Maleviti
Air Traffic Management Principles: A Case Study On How To Create A Sustainable System, Eva Maleviti
Publications
BEYOND ENVIRONMENTAL SUSTAINABILITY
- Emissions, SAF, CORSIA, Design
- Economic growth and development
- Sustainability should go beyond environment
- Non-technology approaches for sustainability and Net-Zero targets
- What about social sustainability and people?
In the total share of aviation emissions (1GT CO2) 3% is 3Mt CO2. Small share but very significant contribution.
Chesapeake Bay Watershed Residents’ And Farmers’ Views On Water Quality, Edem Avemegah, Jessica D. Ulrich-Schad
Chesapeake Bay Watershed Residents’ And Farmers’ Views On Water Quality, Edem Avemegah, Jessica D. Ulrich-Schad
Publications
Poor water quality is an issue in the Chesapeake Bay Watershed (CBW). In this rapidly urbanizing landscape, both farmers and non-farm residents contribute to nutrient pollution of rivers and streams. Understanding these important stakeholders’ views of water quality problems and how to address them is essential for creating an economically thriving and environmentally beneficial agricultural system that all residents depend upon. To understand stakeholder views on water quality both locally and regionally, researchers from Utah State University and the Pennsylvania State University surveyed residents of the CBW and agricultural producers of the southern part of the CBW (Maryland, Delaware, and …
The Evolution Of Ai On The Commercial Flight Deck: Finding Balance Between Efficiency And Safety While Maintaining The Integrity Of Operator Trust, Mark Miller, Sam Holley, Leila Halawi
The Evolution Of Ai On The Commercial Flight Deck: Finding Balance Between Efficiency And Safety While Maintaining The Integrity Of Operator Trust, Mark Miller, Sam Holley, Leila Halawi
Publications
As artificial intelligence (AI) seeks to improve modern society, the commercial aviation industry offers a significant opportunity. Although many parts of commercial aviation including maintenance, the ramp, and air traffic control show promise to integrate AI, the highly computerized digital flight deck (DFD) could be challenging. The researchers seek to understand what role AI could provide going forward by assessing AI evolution on the commercial flight deck over the past 50 years. A modified SHELL diagram is used to complete a Human Factors (HF) analysis of the early use for AI on the commercial flight deck through introduction of the …
Dynamic Function Learning Through Control Of Ensemble Systems, Wei Zhang, Vignesh Narayanan, Jr-Shin Li
Dynamic Function Learning Through Control Of Ensemble Systems, Wei Zhang, Vignesh Narayanan, Jr-Shin Li
Publications
Learning tasks involving function approximation are preva- lent in numerous domains of science and engineering. The underlying idea is to design a learning algorithm that gener- ates a sequence of functions converging to the desired target function with arbitrary accuracy by using the available data samples. In this paper, we present a novel interpretation of iterative function learning through the lens of ensemble dy- namical systems, with an emphasis on establishing the equiv- alence between convergence of function learning algorithms and asymptotic behavior of ensemble systems. In particular, given a set of observation data in a function learning task, we …
Cooperative Deep Q -Learning Framework For Environments Providing Image Feedback, Krishnan Raghavan, Vignesh Narayanan, Sarangapani Jagannathan
Cooperative Deep Q -Learning Framework For Environments Providing Image Feedback, Krishnan Raghavan, Vignesh Narayanan, Sarangapani Jagannathan
Publications
In this article, we address two key challenges in deep reinforcement learning (DRL) setting, sample inefficiency, and slow learning, with a dual-neural network (NN)-driven learning approach. In the proposed approach, we use two deep NNs with independent initialization to robustly approximate the action-value function in the presence of image inputs. In particular, we develop a temporal difference (TD) error-driven learning (EDL) approach, where we introduce a set of linear transformations of the TD error to directly update the parameters of each layer in the deep NN. We demonstrate theoretically that the cost minimized by the EDL regime is an approximation …
Moment-Based Reinforcement Learning For Ensemble Control, Yao-Chi Yu, Vignesh Narayanan, Jr-Shin Li
Moment-Based Reinforcement Learning For Ensemble Control, Yao-Chi Yu, Vignesh Narayanan, Jr-Shin Li
Publications
Problems involving controlling the collective behavior of a population of structurally similar dynamical systems, the so-called ensemble control, arise in diverse emerging applications and pose a grand challenge in systems science and control engineering. Owing to the severely under-actuated nature and the difficulty of placing large-scale sensor networks, ensemble systems are limited to being actuated and monitored at the population level. Moreover, mathematical models describing the dynamics of ensemble systems are often elusive. Therefore, it is essential to design broadcast controls that excite the entire population in such a way that the heterogeneity in system dynamics are robustly compensated. In …
Co-Designing Elementary-Level Computer Science And Mathematics Lessons: An Expansive Framing Approach, Umar Shehzad, Jody Clarke-Midura, Kimberly Beck, Jessica Shumway, Mimi Recker
Co-Designing Elementary-Level Computer Science And Mathematics Lessons: An Expansive Framing Approach, Umar Shehzad, Jody Clarke-Midura, Kimberly Beck, Jessica Shumway, Mimi Recker
Publications
This study examines how a rural-serving school district aimed to provide elementary-level computer science (CS) by offering instruction during students’ computer lab time. As part of a research-practice partnership, cross-context mathematics and CS lessons were co-designed to expansively frame and highlight connections across – as opposed to integration within – the two subjects. Findings indicated that most students who engaged with the lessons across the lab and classroom contexts reported finding the lessons interesting, seeing connections to their mathematics classes, and understanding the programming. In contrast, a three-level logistic regression model showed that students who only learned about mathematics connections …
The Gdpr And Uk Gdpr And Its Impact On Us Academic Institutions, Leila Halawi, Alpesh Makwana
The Gdpr And Uk Gdpr And Its Impact On Us Academic Institutions, Leila Halawi, Alpesh Makwana
Publications
This research paper delves into the implications of the General Data Protection Regulation (GDPR) and the United Kingdom (UK) GDPR on academic institutions, shedding light on their significance for organizations and educational establishments handling data from individuals in the European Union (EU) and the UK. Non-compliance with these regulations can lead to substantial penalties. The study focuses specifically on US Higher Education and presents actionable measures that institutions can adopt to enhance compliance, fortify data protection, and safeguard the privacy of individuals.
Design Of An Internal Osculating Waverider Intake, Mark E. Noftz, Andrew J. Shuck, Joseph S. Jewell, Jonathan Poggie, Andrew N. Bustard, Thomas J. Juliano, Nicholas J. Bisek
Design Of An Internal Osculating Waverider Intake, Mark E. Noftz, Andrew J. Shuck, Joseph S. Jewell, Jonathan Poggie, Andrew N. Bustard, Thomas J. Juliano, Nicholas J. Bisek
Publications
The design of an inward-turning, high-speed, three-dimensional streamline traced intake is presented from osculating axisymmetric theory. To satisfy the osculating intake design criteria, a stitched Busemann diffuser and Internal Conical Flow-A solution is used as the basic isentropic compressive streamline. This new contour provides efficient compression, high flow uniformity, and straight leading edge shocks of equal strength. Additionally, a novel method for constructing the inlet cowl is presented. The combined process leads to a new method of high-speed intake design. A generic shape-transitioned intake is constructed and named the Indiana Inlet for the Indiana universities that contributed to the project. …
Assessing Arrest & Traffic Stop Patterns In Portland, Me, Jack Mcdevitt Ph.D., George Shaler Mph, Sarah Krichels Goan Mpp, Stephen Abeyta, Carlos Cuevas Phd
Assessing Arrest & Traffic Stop Patterns In Portland, Me, Jack Mcdevitt Ph.D., George Shaler Mph, Sarah Krichels Goan Mpp, Stephen Abeyta, Carlos Cuevas Phd
Publications
This project examined the available arrest and traffic citation data from Portland Police Department to determine if there is any evidence of disproportionate enforcement activities in the city.
Two Substellar Survivor Candidates; One Found And One Missing, T. Von Hippel, N. Walters, J. Farihi, T.R. Marsh, E. Breedt, P.W. Cauley, J.J. Hermes
Two Substellar Survivor Candidates; One Found And One Missing, T. Von Hippel, N. Walters, J. Farihi, T.R. Marsh, E. Breedt, P.W. Cauley, J.J. Hermes
Publications
This study presents observations of two possible substellar survivors of post-main sequence engulfment, currently orbiting white dwarf stars. Infrared and optical spectroscopy of GD 1400 reveal a 9.98 h orbital period, where the benchmark brown dwarf has ��2 = 68 ± 8 MJup, ��eff ≈ 2100 K, and a cooling age under 1 Gyr. A substellar mass in the lower range of allowed values is favoured by the gravitational redshift of the primary. Synthetic brown dwarf spectra are able to reproduce the observed CO bands, but lines below the bandhead are notably overpredicted. The known infrared excess towards PG 0010+281 …
One-Parameter Darboux-Deformed Fibonacci Numbers, Stefani C. Mancas, H. C. Rosu
One-Parameter Darboux-Deformed Fibonacci Numbers, Stefani C. Mancas, H. C. Rosu
Publications
One-parameter Darboux deformations are effected for the simple ODE satisfied by the continuous generalizations of the Fibonacci sequence recently discussed by Faraoni and Atieh [Symmetry 13, 200 (2021)], who promoted a formal analogy with the Friedmann equation in the FLRW homogeneous cosmology. The method allows the introduction of deformations of the continuous Fibonacci sequences, hence of Darboux-deformed Fibonacci (non integer) numbers. Considering the same ODE as a parametric oscillator equation, the Ermakov-Lewis invariants for these sequences are also discussed.
On A Guiding Of Whistler-Mode Waves By Density Gradients, Anatoly V. Streltsov
On A Guiding Of Whistler-Mode Waves By Density Gradients, Anatoly V. Streltsov
Publications
Observations from satellites demonstrate that in the magnetosphere, VLF whistler-mode waves are frequently detected in the narrow transition regions, where the plasma density changes its magnitude over a short distance across the ambient magnetic field. These observations suggest that the small-scale, isolated density gradients can guide the VLF whistler-mode waves along the field. We investigate the guiding of the whistler-mode waves by the transverse density gradients with a size much less than the characteristic perpendicular size of the wave. We found analytical solutions describing these waves in the plasma with a sharp density discontinuity between two homogeneous regions, and confirm …
Wavenumbers 3 And 4 Quasi 2-Day Wave Activities Observed By Multiple Meteor Radars In The Two Hemispheres During Austral Summer, Hao Cheng, Kai Ming Huang, Alan Z. Liu, Shao Dong Zhang, Chun Ming Huang, Yun Gong
Wavenumbers 3 And 4 Quasi 2-Day Wave Activities Observed By Multiple Meteor Radars In The Two Hemispheres During Austral Summer, Hao Cheng, Kai Ming Huang, Alan Z. Liu, Shao Dong Zhang, Chun Ming Huang, Yun Gong
Publications
Combining observations from three meteor radars in the Northern Hemisphere (NH) and a meteor radar in the Southern Hemisphere (SH) and reanalysis data, we present successive wavenumbers 3 and 4 (W3 and W4) quasi 2 day wave activities in austral summer. In the mesosphere and lower thermosphere, the wave exhibits two burst activities. The W3 dominates the first burst, while the W4 is the predominate mode in the second burst. The mode transition arises in the late January and is completed around the end of January. The W3 and W4 have the nearly same dominate period of about 46 hr …
Coupling Evidence From Lower Atmosphere To Mesosphere And Ionosphere Through Quasi 27-Day Oscillation, Alan Z. Liu, Kaiming Huang, Hao Cheng, Shaodong Zhang, Chunming Huang, Yun Gong, Gang Chen
Coupling Evidence From Lower Atmosphere To Mesosphere And Ionosphere Through Quasi 27-Day Oscillation, Alan Z. Liu, Kaiming Huang, Hao Cheng, Shaodong Zhang, Chunming Huang, Yun Gong, Gang Chen
Publications
Using meteor radar, radiosonde and digisonde observations and MERRA-2 reanalysis data from 12 August to 31 October 2006, we report a dynamical coupling from the tropical lower atmosphere to the mesosphere and ionospheric F2 region through a quasi 27-day intraseasonal oscillation (ISO). It is interesting that the quasi 27-day ISO is active in the troposphere and stratopause and mesopause regions, exhibiting a three-layer structure. In the mesosphere and lower thermosphere (MLT), the amplitude in the zonal wind increases from about 4 ms at 90 km to 15 ms at 100 km, which is different from previous observations that ISOs generally …