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Articles 211 - 240 of 1383
Full-Text Articles in Physical Sciences and Mathematics
Artificial Intelligence (Ai) And Augmented Reality (Ar): Disambiguated In The Telemedicine / Telehealth Sphere, Sharon L. Burton
Artificial Intelligence (Ai) And Augmented Reality (Ar): Disambiguated In The Telemedicine / Telehealth Sphere, Sharon L. Burton
Publications
The world is navigating through unfamiliar and incomprehensible times – COVID-19, international economic crisis, and crumbling healthcare systems. The United States (US) healthcare industry is grappling with an increased workload and advancing digitization technological concerns. The failure of organizations to offer suitable cybersecurity controls within the critical infrastructure leads to advanced persistent threat (APT) that could have incapacitating effects on organizations. A keen understanding of cybersecurity is vital for leaders and the need is referenced in US policy that advances a national unity of effort to strengthen and maintain secure, functioning, and resilient critical infrastructure. Akin to the Presidential Policy …
The Economic Value Of America’S Estuaries: 2021 Report, Tracy Rouleau, Charles S. Colgan, Jefferey Adkins, Castelletto Anthony, Dirlam Patty, Shannon Lyons, Hilary Stevens
The Economic Value Of America’S Estuaries: 2021 Report, Tracy Rouleau, Charles S. Colgan, Jefferey Adkins, Castelletto Anthony, Dirlam Patty, Shannon Lyons, Hilary Stevens
Publications
This study builds on the work completed in 2009, “The Economic and Market Value of Coasts and Estuaries: What’s At Stake?,” a report by NOAA in collaboration with the Center for the Blue Economy and the Ocean Foundation, at the request of Restore America’s Estuaries. Like the 2009 study, the 2021 update uses the same data sources (Census, Bureau of Labor Statistics, Bureau of Economic Analysis and NOAA), and looks in detail at the same five major sectors of the U.S. economy (fisheries, energy infrastructure, marine transportation, real estate, and recreation) from 2009-2018.
The 2021 update includes the economic …
Inferring The Evolution Of A Large Earthquake From Its Acoustic Impacts On The Ionosphere, P. A. Inchin, J. B. Snively, M. D. Zettergren, Y. Kaneko, A. Komjathy
Inferring The Evolution Of A Large Earthquake From Its Acoustic Impacts On The Ionosphere, P. A. Inchin, J. B. Snively, M. D. Zettergren, Y. Kaneko, A. Komjathy
Publications
We investigate the possibility to constrain the evolution of the 2016 M7.8 Kaikoura earthquake evolution based on Global Positioning System signal-derived ionospheric total electron content (TEC) perturbations, that represent plasma responses to infrasonic acoustic waves (IAWs) generated by surface motion. This earthquake exhibited unusual complexity and some first-order aspects of its evolution remain unclear; for example, how and when the Papatea fault (PF) and the corresponding large surface deformation occurred. For various earthquake models, a seismic wave propagation code is used to simulate time-dependent surface deformations, which then excite IAWs in a 3D compressible nonlinear atmospheric model, coupled with a …
Atmospheric Tomography Using The Nordic Meteor Radar Cluster And Chilean Observation Network De Meteor Radars: Network Details And 3dvar Retrieval, Gunter Stober, Alan Liu, Zishun Qiao, Alexander Kozlovsky, Masaki Tsutsumi, Chris Hall, Satonori Nozawa, Mark Lester, Evgenia Belova, Johan Kero, Patrick J. Espy, Robert E. Hibbins, Nicholas Mitchell
Atmospheric Tomography Using The Nordic Meteor Radar Cluster And Chilean Observation Network De Meteor Radars: Network Details And 3dvar Retrieval, Gunter Stober, Alan Liu, Zishun Qiao, Alexander Kozlovsky, Masaki Tsutsumi, Chris Hall, Satonori Nozawa, Mark Lester, Evgenia Belova, Johan Kero, Patrick J. Espy, Robert E. Hibbins, Nicholas Mitchell
Publications
Ground-based remote sensing of atmospheric parameters is often limited to single station observations of vertical profiles at a certain geographic location. This can be a limiting factor to investigating gravity wave dynamics. In this study we present a new retrieval algorithm for multi-static meteor radar networks to obtain tomographic 3D wind fields within a pre-defined domain area. The algorithm is part of the Agile Software for Gravity wAve Regional Dynamics (ASGARD) called 5 3DVAR, and based on the optimal estimation technique and Bayesian statistics. The performance of the 3DVAR retrieval is demonstrated using two meteor radar networks, the Nordic Meteor …
Ieee Access Special Section Editorial: Software-Defined Networks For Energy Internet And Smart Grid Communication, Mubashir Husain Rehmani, Alan Davy, Brendan Jennings, Zeeshan Kaleem, Akhilesh S. Thyagaturu, Hassnaa Moustafa, Al-Sakib Khan Pathan
Ieee Access Special Section Editorial: Software-Defined Networks For Energy Internet And Smart Grid Communication, Mubashir Husain Rehmani, Alan Davy, Brendan Jennings, Zeeshan Kaleem, Akhilesh S. Thyagaturu, Hassnaa Moustafa, Al-Sakib Khan Pathan
Publications
A new network paradigm of software-defined networks (SDNs) is being widely adapted to efficiently monitor and manage the communication networks with a global perspective. SDN has a key networking feature that separates control and data plane. Today, due to its inherent benefits, SDN has been widely applied to various networking domains, including data centers, 5G Access and Core network functions, wide area network (WAN), enterprise, optical networks, underwater sensor networks (UWSNs), energy Internet (EI), and smart grid (SG).
Improving Access And Health Outcomes Through Carepartners And Medaccess Programs, Elora Way, Becky Wurwarg
Improving Access And Health Outcomes Through Carepartners And Medaccess Programs, Elora Way, Becky Wurwarg
Publications
Access to Care, a division of MaineHealth, works to ensure that Maine residents have access to comprehensive and affordable healthcare that improves community wellbeing. In 2020, as part of its ongoing commitment to evaluating the effectiveness of its programs, Access to Care partnered with the University of Southern Maine’s Data Innovation Project to conduct a multi-year retrospective evaluation of its two longest-running initiatives, CarePartners and MedAccess. Established in 2001, CarePartners coordinates donated healthcare services for low-income, uninsured residents across six Maine counties by connecting participants with case managers, primary care providers, and pharmacy benefits. Between 2016 and 2019, 4,426 individuals …
Cross Domain Iw Threats To Sof Maritime Missions: Implications For U.S. Sof, Gary C. Kessler, Diane M. Zorri
Cross Domain Iw Threats To Sof Maritime Missions: Implications For U.S. Sof, Gary C. Kessler, Diane M. Zorri
Publications
As cyber vulnerabilities proliferate with the expansion of connected devices, wherein security is often forsaken for ease of use, Special Operations Forces (SOF) cannot escape the obvious, massive risk that they are assuming by incorporating emerging technologies into their toolkits. This is especially true in the maritime sector where SOF operates nearshore in littoral zones. As SOF—in support to the U.S. Navy— increasingly operate in these contested maritime environments, they will gradually encounter more hostile actors looking to exploit digital vulnerabilities. As such, this monograph comes at a perfect time as the world becomes more interconnected but also more vulnerable.
Control Over Skies: Survivability, Coverage, And Mobility Laws For Hierarchical Aerial Base Stations, Vishal Sharma, Navuday Sharma, Mubashir Husain Rehmani, Haris Pervaiz
Control Over Skies: Survivability, Coverage, And Mobility Laws For Hierarchical Aerial Base Stations, Vishal Sharma, Navuday Sharma, Mubashir Husain Rehmani, Haris Pervaiz
Publications
Aerial Base Stations (ABSs) have gained significant importance in the next generation of wireless networks for accommodating mobile ground users and flash crowds with high convenience and quality. However, to achieve an efficient ABS network, many factors pertaining to ABS flight, governing laws and information transmissions must be studied. In this article, multi-drone communications are studied in three major aspects, survivability, coverage, and mobility laws, which optimize the multitier ABS network to avoid issues related to inter-cell interference, deficient energy, frequent handovers, and lifetime. The article includes simulation results of hierarchical ABS allocations for handling a set of users over …
Cyber Supply Chain Risk Management: Implications For The Sof Future Operating Environment, J. Philip Craiger, Laurie Lindamood-Craiger, Diane M. Zorri
Cyber Supply Chain Risk Management: Implications For The Sof Future Operating Environment, J. Philip Craiger, Laurie Lindamood-Craiger, Diane M. Zorri
Publications
The emerging Cyber Supply Chain Risk Management (C-SCRM) concept assists at all levels of the supply chain in managing and mitigating risks, and the authors define C-SCRM as the process of identifying, assessing, and mitigating the risks associated with the distributed and interconnected nature of information and operational technology products and service supply chains. As Special Operations Forces increasingly rely on sophisticated hardware and software products, this quick, well-researched monograph provides a detailed accounting of C-SCRM associated laws, regulations, instructions, tools, and strategies meant to mitigate vulnerabilities and risks—and how we might best manage the evolving and ever-changing array of …
Cyber Security Framework For Vehicular Network Based On A Hierarchical Game, Hichem Sedjelmaci, Imane Horiya Brahmi, Nirwan Ansari, Mubashir Husain Rehmani
Cyber Security Framework For Vehicular Network Based On A Hierarchical Game, Hichem Sedjelmaci, Imane Horiya Brahmi, Nirwan Ansari, Mubashir Husain Rehmani
Publications
The growth of electronic devices in connected vehicles and their connections to the untrusted network, present unprecedented exposure to attacks. Therefore, a reliable and efficient cyber security framework is mandatory to protect vehicular networks against the cyber attackers. Thereby, we propose a cyber defense framework based on a hierarchical cooperative game to secure legitimate vehicles from attacks. In the proposed hierarchical game, there are two kinds of players, the head agent and secondary agents that cooperate between each other to detect, predict and react efficiently against suspected attacks. The Intrusion Detection System (IDS), Intrusion Prediction System (IPS), and Intrusion Reaction …
Aspirations Incubator: 2017–2023 Interim Evaluation Report, Sarah Goan, Elora Way, Alexa Plotkin
Aspirations Incubator: 2017–2023 Interim Evaluation Report, Sarah Goan, Elora Way, Alexa Plotkin
Publications
The Emanuel & Pauline A. Lerner Foundation’s Aspirations Incubator (AI) is a six-year pilot initiative invested in strategic capacity building for six youth development organizations in rural Maine. Grounded in the Trekkers Youth Programming Principles, the Aspirations Incubator invests targeted resources to provide long-term, comprehensive relationship-based programming to youth. This structured yet flexible program model aims to increase resiliency and introduce new opportunities to cohorts of young people starting in 7th grade and continuing through high school graduation. To document the potential impact and effectiveness of this unique model, the Lerner Foundation contracted with the Data Innovation Project to conduct …
Investigation On Spectral Characteristics Of Gravity Waves In The Mlt Using Lidar Observations At Andes, Kai Ming Huang, Hang Liu, Alan Z. Liu, Shao Dong Zhang, Chun Ming Huang, Yun Gong, Wu Han Ning
Investigation On Spectral Characteristics Of Gravity Waves In The Mlt Using Lidar Observations At Andes, Kai Ming Huang, Hang Liu, Alan Z. Liu, Shao Dong Zhang, Chun Ming Huang, Yun Gong, Wu Han Ning
Publications
Based on observations from lidar at Andes, we study the features of gravity wave activities and their spectra in the mesosphere and lower thermosphere (MLT). Case analysis shows that a quasimonochromatic inertia–gravity wave (IGW) dominates the perturbation fields, with clearly downward phase progression in the wind and temperature fields. Statistical investigation shows that the dominant waves in the MLT over Andes have the typical temporal and spatial scales of IGWs and show the preferential propagation in the meridional direction relative to in the zonal direction. The preferential propagation direction causes larger spectral peak and steeper spectral slope in the meridional …
Investigating The Impacts Of Crash Prediction Models On Quantifying Safety Effectiveness Of Adaptive Signal Control Systems, Weimin Jin, Mashrur Chowdhury, Sakib Mahmud Khan, Patrick Gerard
Investigating The Impacts Of Crash Prediction Models On Quantifying Safety Effectiveness Of Adaptive Signal Control Systems, Weimin Jin, Mashrur Chowdhury, Sakib Mahmud Khan, Patrick Gerard
Publications
Introduction: Adaptive Signal Control System (ASCS) can improve both operational and safety benefits at signalized corridors. Methods: This paper develops a series of models accounting for model forms and possible predictors and implements these models in Empirical Bayes (EB) and Fully Bayesian (FB) frameworks for ASCS safety evaluation studies. Different models are validated in terms of the ability to reduce the potential bias and variance of prediction and improve the safety effectiveness estimation accuracy using real-world crash data from non-ASCS sites. This paper then develops the safety effectiveness of ASCS at six different corridors with a total of 65 signalized …
Parking Recommender System Privacy Preservation Through Anonymization And Differential Privacy, Yasir Saleem Shaikh, Mubashir Husain Rehmani, Noel Crespi, Roberto Minerva
Parking Recommender System Privacy Preservation Through Anonymization And Differential Privacy, Yasir Saleem Shaikh, Mubashir Husain Rehmani, Noel Crespi, Roberto Minerva
Publications
Recent advancements in the Internet of Things (IoT) have enabled the development of smart parking systems that use services of third-party parking recommender system to provide recommendations of personalized parking spot to users based on their past experience. However, the indiscriminate sharing of users’ data with an untrusted (or semitrusted) parking recommender system may breach the privacy because users’ behavior and mobility patterns could be inferred by analyzing their past history. Therefore, in this article, we present two solutions that preserve privacy of users in parking recommender systems while analyzing the past parking history using k-anonymity (anonymization) and differential privacy …
Knowledge Network Embedding Of Transcriptomic Data From Spaceflown Mice Uncovers Signs And Symptoms Associated With Terrestrial Diseases, Amber M. Paul, Charlotte A. Nelson, Ana Uriarte Acuna, Ryan T. Scott, Atul J. Butte, Egle Cekanaviciute, Sergio E. Baranzini
Knowledge Network Embedding Of Transcriptomic Data From Spaceflown Mice Uncovers Signs And Symptoms Associated With Terrestrial Diseases, Amber M. Paul, Charlotte A. Nelson, Ana Uriarte Acuna, Ryan T. Scott, Atul J. Butte, Egle Cekanaviciute, Sergio E. Baranzini
Publications
There has long been an interest in understanding how the hazards from spaceflight may trigger or exacerbate human diseases. With the goal of advancing our knowledge on physiological changes during space travel, NASA GeneLab provides an open-source repository of multi-omics data from real and simulated spaceflight studies. Alone, this data enables identification of biological changes during spaceflight, but cannot infer how that may impact an astronaut at the phenotypic level. To bridge this gap, Scalable Precision Medicine Oriented Knowledge Engine (SPOKE), a heterogeneous knowledge graph connecting biological and clinical data from over 30 databases, was used in combination with GeneLab …
The Causal Topology Of Neutral 4-Manifolds With Null Boundary, Nikos Georgiou, Brendan Guilfoyle
The Causal Topology Of Neutral 4-Manifolds With Null Boundary, Nikos Georgiou, Brendan Guilfoyle
Publications
This paper considers aspects of 4-manifold topology from the point of view of the null cone of a neutral metric, a point of view we call neutral causal topology. In particular, we construct and investigate neutral 4-manifolds with null boundaries that arise from canonical 3- and 4-dimensional settings. A null hypersurface is foliated by its normal and, in the neutral case, inherits a pair of totally null planes at each point. This paper focuses on these plane bundles in a number of classical settings The first construction is the conformal compactification of flat neutral 4- space into the 4-ball. The …
Semantics Of The Black-Box: Can Knowledge Graphs Help Make Deep Learning Systems More Interpretable And Explainable?, Manas Gaur, Keyur Faldu, Amit Sheth
Semantics Of The Black-Box: Can Knowledge Graphs Help Make Deep Learning Systems More Interpretable And Explainable?, Manas Gaur, Keyur Faldu, Amit Sheth
Publications
The recent series of innovations in deep learning (DL) have shown enormous potential to impact individuals and society, both positively and negatively. The DL models utilizing massive computing power and enormous datasets have significantly outperformed prior historical benchmarks on increasingly difficult, well-defined research tasks across technology domains such as computer vision, natural language processing, signal processing, and human-computer interactions. However, the Black-Box nature of DL models and their over-reliance on massive amounts of data condensed into labels and dense representations poses challenges for interpretability and explainability of the system. Furthermore, DLs have not yet been proven in their ability to …
The Impact Of Covid-19 On Volunteering:Results Of A Survey Of Maine Non-Profits, Sarah Goan
The Impact Of Covid-19 On Volunteering:Results Of A Survey Of Maine Non-Profits, Sarah Goan
Publications
In response to the disruptions caused by the COVID-19 pandemic, particularly within the nonprofit sector that relies heavily on volunteers, Volunteer Maine sought to assess how volunteer capacity had been affected and what types of support organizations needed to rebuild. To accomplish this, the organization partnered with DIP and SRC to design and administer a statewide survey of nonprofit organizations. The purpose of the study was to understand the pandemic’s impact on the volunteer base, document organizational adjustments to changing conditions, identify innovative responses, and determine how Volunteer Maine and its affiliates could best assist in community recovery efforts. The …
How To Draft An Sop?, Emily Faulconer
How To Draft An Sop?, Emily Faulconer
Publications
ERAU offers resources to support SOP development.
We can streamline efforts by learning from the past.
• Do not write an SOP for an individual process or action, it should be a part of the larger process.
• Disregard the first sentence if the material is so dangerous that it needs its own SOP created.
• If you are having trouble, stop and ask for assistance. The process can become frustrating.
• Be specific (what size container, slow/fast pour, what speed to mix at).
• Do not refer to other checklists if at all possible, multiple SOPs/checklists can cause errors/mistakes. …
Fracking Florida, Emily Faulconer
Fracking Florida, Emily Faulconer
Publications
- Traditional Hydraulic Fracturing
- Why Frack?
- Why it’s Controversial
- Acid Fracking
- What’s in the Wastewater?
- Ethylene Glycol
- 2-Butoxyethanol
- Benzene
- So Where Does the Wastewater Go?
- “Halliburton Loophole”
- Drilling in Florida
- Timeline of Events at Collier-Hogan Well
- Lease Termination & Permit Revocation
- Frack Fluid used at Collier-Hogan Well
- Groundwater Monitoring Wells
- FDEP Tested 142 Analytes
- House Bills 71 & 157: Fracturing Chemical Usage Disclosure Act
- Proposed Sabal Trail Pipeline
- Hands Across the Sand” Rally
- My $0.02
Cyber Insurance Effects On Cyber Hygiene: Does The Homeostatic Effect Apply?, Wendi M. Kappers, Aaron Glassman, Michael S. Wills
Cyber Insurance Effects On Cyber Hygiene: Does The Homeostatic Effect Apply?, Wendi M. Kappers, Aaron Glassman, Michael S. Wills
Publications
A theoretical framework and research strategy is proposed to gain insight into perceptions and decisions as to how SMBs make decisions regarding cybersecurity hygiene measures, which could lead to betterinformed decisions regarding insurance as part of an ISA program, as well as have a bearing on policy structures and pricing for such insurance. This is because the definition of “cybersecurity hygiene habits”(CHH) as a task appears to vary within the industry and makes the practice hard to measure and evaluate. Research suggests that there may be a poorly understood connection between CHHs undertaken by organizations and their perceptions and/or adoption …
"Who Can Help Me?'': Knowledge Infused Matching Of Support Seekers And Support Providers During Covid-19 On Reddit, Manas Gaur, Kaushik Roy, Aditya Sharma, Biplav Srivastava, Amit Sheth
"Who Can Help Me?'': Knowledge Infused Matching Of Support Seekers And Support Providers During Covid-19 On Reddit, Manas Gaur, Kaushik Roy, Aditya Sharma, Biplav Srivastava, Amit Sheth
Publications
During the ongoing COVID-19 crisis, subreddits on Reddit, such as r/Coronavirus saw a rapid growth in user's requests for help (support seekers - SSs) including individuals with varying professions and experiences with diverse perspectives on care (support providers - SPs). Currently, knowledgeable human moderators match an SS with a user with relevant experience, i.e, an SP on these subreddits. This unscalable process defers timely care. We present a medical knowledge-infused approach to efficient matching of SS and SPs validated by experts for the users affected by anxiety and depression, in the context of with COVID-19. After matching, each SP to …
Transitioning To An Active Learning Environment For Calculus At The University Of Florida, Darryl Chamberlain, Amy Grady, Scott Keeran, Kevin Knudson, Ian Manly, Melissa Shabazz, Corey Stone
Transitioning To An Active Learning Environment For Calculus At The University Of Florida, Darryl Chamberlain, Amy Grady, Scott Keeran, Kevin Knudson, Ian Manly, Melissa Shabazz, Corey Stone
Publications
In this note, we describe a large-scale transition to an active learning format in first-semester calculus at the University of Florida. Student performance and attitudes are compared across traditional lecture and flipped sections.
Cybersecurity Leaders: Knowledge Driving Human Capital Development, Sharon L. Burton
Cybersecurity Leaders: Knowledge Driving Human Capital Development, Sharon L. Burton
Publications
Cybersecurity leaders must be able to use critical reading and thinking skills, exercise judgment when policies are not distinct and precise, and have the knowledge, skills, and abilities to tailor technical and planning data to diverse customers’ levels of understanding. Ninety-three percent of cybersecurity leaders do not report directly to the chief operating officer. While status differences influence interactions amid groups, attackers are smarter. With the aim of protecting organizations and reducing risk, knowledge about security must increase. Understanding voids are costly and increased breach chances are imminent. Burning questions exist. What are needed technological learnings for cybersecurity leaders to …
Gravity Waves, Na Lidar, Yafang Guo, Alan Z. Liu
Gravity Waves, Na Lidar, Yafang Guo, Alan Z. Liu
Publications
Vertical energy transports due to dissipating gravity waves in the mesopause region (85–100 km) are analyzed using over 400 h of observational data obtained from a narrow-band sodium wind-temperature lidar located at Andes Lidar Observatory (ALO), Cerro Pachón (30.25°S, 70.73°W), Chile. Sensible heat flux is directly estimated using measured temperature and vertical wind; energy flux is estimated from the vertical wavenumber and frequency spectra of temperature perturbations; and enthalpy flux is derived based on its relationship with sensible heat and energy fluxes. Sensible heat flux is mostly downward throughout the region. Enthalpy flux exhibits an annual oscillation with maximum downward …
Seasonal Variation Of Vertical Heat And Energy Fluxes Due To Dissipating Gravity Waves In The Mesopause Region Over The Andes, Yafang Guo, Alan Z. Liu
Seasonal Variation Of Vertical Heat And Energy Fluxes Due To Dissipating Gravity Waves In The Mesopause Region Over The Andes, Yafang Guo, Alan Z. Liu
Publications
Vertical energy transports due to dissipating gravity waves in the mesopause region (85–100 km) are analyzed using over 400 h of observational data obtained from a narrow-band sodium wind-temperature lidar located at Andes Lidar Observatory (ALO), Cerro Pachón (30.25°S, 70.73°W), Chile. Sensible heat flux is directly estimated using measured temperature and vertical wind; energy flux is estimated from the vertical wavenumber and frequency spectra of temperature perturbations; and enthalpy flux is derived based on its relationship with sensible heat and energy fluxes. Sensible heat flux is mostly downward throughout the region. Enthalpy flux exhibits an annual oscillation with maximum downward …
Nearly 30,000 Late-Type Main-Sequence Stars With Stellar Age From Lamost Dr5, Jiajun Zhang, Terry D. Oswalt, Jingkun Zhao, Xilong Liang, Xianhao Ye, Gang Zhao
Nearly 30,000 Late-Type Main-Sequence Stars With Stellar Age From Lamost Dr5, Jiajun Zhang, Terry D. Oswalt, Jingkun Zhao, Xilong Liang, Xianhao Ye, Gang Zhao
Publications
We construct a sample of nearly 30,000 main-sequence stars with 4500K < Teff < 5000K and stellar ages estimated by the chromospheric activity−age relation. This sample is used to determine the age distribution in the R − Z plane of the Galaxy, where R is the projected Galactocentric distance in the disk midplane and Z is the height above the disk midplane. As |Z| increases, the percentage of old stars becomes larger. It is known that scale-height of Galactic disk increases as R increases, which is called flare. A mild flare from R ∼ 8.0 to 9.0 kpc in stellar age distribution is found. We also find that the velocity dispersion increases with age as confirmed by previous studies. Finally we present spiral-shaped structures in Z − υZ phase space in three stellar age bins. The spiral is clearly seen in the age bin of [0, 1] Gyr, which suggests that a vertical perturbation to the disk probably took place within the last ∼ 1.0 Gyr.
Fredholm-Regularity Of Holomorphic Discs In Plane Bundles Over Compact Surfaces, Brendan Guilfoyle, Wilhelm Klingenberg
Fredholm-Regularity Of Holomorphic Discs In Plane Bundles Over Compact Surfaces, Brendan Guilfoyle, Wilhelm Klingenberg
Publications
We study the space of holomorphic discs with boundary on a surface in a real 2-dimensional vector bundle over a compact 2-manifold. We prove that, if the ambient 4-manifold admits a fibre-preserving transitive holomorphic action, then a section with a single complex point has C2,α-close sections such that any (non-multiply covered) holomorphic disc with boundary in these sections are Fredholm regular. Fredholm regularity is also established when the complex surface is neutral K¨ahler, the action is both holomorphic and symplectic, and the section is Lagrangian with a single complex point.
The Dynamics Of Nonlinear Atmospheric Acoustic-Gravity Waves Generated By Tsunamis Over Realistic Bathymetry, P. A. Inchin, C. J. Heale, J. B. Snively, M. D. Zettergren
The Dynamics Of Nonlinear Atmospheric Acoustic-Gravity Waves Generated By Tsunamis Over Realistic Bathymetry, P. A. Inchin, C. J. Heale, J. B. Snively, M. D. Zettergren
Publications
The investigation of atmospheric tsunamigenic acoustic and gravity wave (TAGW) dynamics, from the ocean surface to the thermosphere, is performed through the numerical computations of the 3D compressible nonlinear Navier-Stokes equations. Tsunami propagation is first simulated using a nonlinear shallow water model, which incorporates instantaneous or temporal evolutions of initial tsunami distributions (ITD). Ocean surface dynamics are then imposed as a boundary condition to excite TAGWs into the atmosphere from the ground level. We perform a case study of a large tsunami associated with the 2011 M9.1 Tohuku-Oki earthquake and parametric studies with simplified and demonstrative bathymetry and ITD. Our …
Kelvin-Helmholtz Billow Interactions And Instabilities In The Mesosphere Over The Andes Lidar Observatory: 1. Observations, J. H. Hecht, R. L. Walterscheid, A. Z. Liu, D. C. Fritts, L. J. Gelinas, R. J. Rudy
Kelvin-Helmholtz Billow Interactions And Instabilities In The Mesosphere Over The Andes Lidar Observatory: 1. Observations, J. H. Hecht, R. L. Walterscheid, A. Z. Liu, D. C. Fritts, L. J. Gelinas, R. J. Rudy
Publications
A very high spatial resolution (∼25 m pixel at 90 km altitude) OH airglow imager was installed at the Andes Lidar Observatory on Cerro Pachón, Chile, in February 2016. This instrument was collocated with a Na wind-temperature lidar. On 1 March 2016, the lidar data showed that the atmosphere was dynamically unstable before 0100 UT and thus conducive to the formation of Kelvin-Helmholtz instabilities (KHIs). The imager revealed the presence of a KHI and an apparent atmospheric gravity wave (AGW) propagating approximately perpendicular to the plane of primary KHI motions. The AGW appears to have induced modulations of the shear …