A5070425262- Underwater Acoustics Research
- Oceanographic and Atmospheric Processes
- Underwater Vehicles and Communication Systems
- Marine animal studies overview
- Reservoir Engineering and Simulation Methods
- Seismic Imaging and Inversion Techniques
- Marine and environmental studies
- Global Energy and Sustainability Research
- Tropical and Extratropical Cyclones Research
- Particle accelerators and beam dynamics
- Seismic Waves and Analysis
- Fusion materials and technologies
- Orbital Angular Momentum in Optics
- Nuclear and radioactivity studies
- Geological and Geophysical Studies
- Methane Hydrates and Related Phenomena
Georgia Institute of Technology
1997-2025
Ocean acoustic tomography (OAT) methods aim at estimating variations of sound speed profiles (SSP) based on measurements between multiple source-receiver pairs (e.g., eigenray travel times). This study investigates the estimation range-dependent SSPs in upper ocean over short ranges (<5 km) using classical ray-based OAT formulation as well iterative or adaptive formulations (i.e., when sources and receivers configuration can evolve across successive iterations this inverse problem). A...
This study evaluates the impact of ocean model vertical resolution in representing three-dimensional (3D) sound speed variability used for acoustic predictions upper ocean. Sound propagation is investigated two configurations same regional circulation De Soto Canyon northern Gulf Mexico. Both employ a submesoscale-permitting horizontal 0.5 km but differ resolution, featuring 30 or 200 terrain-following layers. The higher found to better represent oceanographic features, such as submesoscale...
A generative deep learning framework is introduced for ray-based ocean acoustic tomography (OAT), an inverse problem estimating sound speed profiles (SSP) based on arrival-times measurements between multiple transducers, which typically ill-posed. This relies a robust low-dimensional parametrization of the expected SSP variations using variational autoencoder and linear dynamical model as further regularization. was tested simulated by regional with submesoscale permitting horizontal...
This work demonstrates the feasibility of using autonomous surface vehicles equipped with a shallow towed acoustic module (TAM) to survey spatial variability low-frequency propagation across complex bathymetry, such as Atlantis II seamounts in Northwest Atlantic. The abrupt seamount topography is found significantly influence TAM's recordings chirp transmissions (500–600 Hz band) from bottom-moored source ∼30 km by notably causing blockage in-plane paths and reverberation arrivals displaying...
The effects of topographically generated lee waves on acoustic propagation near the Atlantis II seamount in New England Seamount area are investigated using Coastal and Regional Ocean Community model. Submesoscale permitting ocean circulation simulations were conducted to model formation characteristics waves, analyze their hydrographic impact sound speed profiles, assess influence sonic layer duct (SLAD) propagation. Lee significantly alter affecting deep channel depth. These alterations...
This work investigates how vertical resolution affects the prediction of ocean sound speed through a suite regional simulations covering DeSoto Canyon in Gulf Mexico. Simulations have identical horizontal 0.5 km, partially resolving submesoscale dynamics, and from 30 to 200 terrain-following layers. The focus is on mesoscale eddies modeled speeds vary whenever more baroclinic modes are resolved. While domain-averaged profiles do not differ substantively, standard deviation increases for...
Abstract This study investigates the complex interactions between North Atlantic Current (NAC) and New England Seamount chain, focusing on Atlantis II seamount. Employing a high‐resolution submesoscale permitting regional ocean circulation model nested within basin‐wide simulation, it explores three distinct periods, each 2 weeks long, showcasing varied deep mesoscale circulations around The analysis includes Eulerian statistics Lagrangian particle tracing experiments to explore transport...
A concept is presented for a fusion neutron source based tritium production reactor called the Tokamak Tritium Production Reactor (TTPR), which could meet U.S. needs replenishment of weapons during first half next century. The TTPR on physics and technology that either exists or being developed will be tested under integrated, prototypical conditions in International Thermonuclear Experimental (ITER). can provide 2 kg/yr operating at power level 500 to 1000 MW plant factor 10 25%. No...
Inverse problems describe the task of recovering an underlying signal interest given observables. Typically, observables are related via some non-linear forward model applied to unknown signal. Inverting can be computationally expensive, as it often involves computing and inverting a linearization at series estimates. Rather than physics-based model, we instead train surrogate (emulator) leverage modern auto-grad libraries solve for input within classical optimization framework. Current...
Acoustic vortex beams have garnered recent interest as an avenue to improve underwater acoustic communication bandwidth and speed. Design deployment of these systems in ocean environments at operational ranges has yet be demonstrated due the challenging dynamic nature environment. This manuscript presents methods model time series vortex-based signals using ray tracing algorithms. The are used assess effects Doppler, turbulence, positional error, range-dependent environmental parameters on...
This study investigates the impact of three-dimensional (3-D) bathymetry and sound speed variability on propagation, utilizing 3-D ray tracing compared to simple two-dimensional (Nx2-D) within New England seamount chain, focusing Atlantis II area. The research has three main objectives. First, it examines differences between 2-D acoustic propagation modeling bathymetric reflections. Second, evaluates physical oceanographic effects versus modeling, employing a high-resolution regional ocean...
Accurately modeling acoustic propagation in dynamic ocean environments exhibiting sub-mesoscale variability is challenging. Such require high-resolution circulation model to accurately predict local sound speed at sub-mesoscales. This study focuses on rendition of the De Soto canyon area, located Gulf Mexico. Predicted profiles were found times exhibit very strong vertical gradients (e.g. with sharp “elbows”) reflecting small-scale variations layer properties. If used as raw inputs for...
Accurate knowledge of the spatial and temporal evolution three-dimensional ocean sound speed profile (SSP) is crucial for underwater source localization. Ocean acoustic tomography (OAT) methods aim at reconstructing SSPs variations based on measurements between multiple source-receiver pairs (e.g., eigenrays arrival times). This study investigates estimation range-dependent using a classical model-based OAT method (i.e., ray-based tomography), various configurations receiver autonomous...
Accurate numerical simulations of underwater acoustic propagation in a dynamic ocean—and its associated uncertainty—require using realistic environmental parameters as inputs and especially high-fidelity representation the expected spatio-temporal variability ocean sound speed volume interest. In areas characterized by strong temperature salinity variations (e.g., with long-living mesoscale eddies Gulf Mexico), approximate simulation 3D sound-speed field requires predictive oceanographic...