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Detection, classification and localization of seabed objects with a virtual time reversal mirror
(Massachusetts Institute of Technology, 2009)
The work presented in this thesis addresses the problem of the detection, classification and localization of seabed objects in shallow water environments using a time reversal approach in a bistatic configuration. The ...
Quantification of the spatial and temporal evolution of stratified shear instabilities at high Reynolds number using quantitative acoustic scattering techniques
(Massachusetts Institute of Technology, 2015)
The spatial and temporal evolution of stratified shear instabilities is quantified in a highly stratified and energetic estuary. The measurements are made using high-resolution acoustic backscatter from an array composed ...
Physical control of the distributions of a key Arctic copepod in the Northeast Chukchi Sea
(Massachusetts Institute of Technology, 2015)
The copepod Calanus glacialis is one of the most important zooplankton taxa in the Arctic shelf seas where it serves as a key grazer, predator, and food source. Its summer distribution and abundance has direct effects on ...
Sparse Bayesian information filters for localization and mapping
(Massachusetts Institute of Technology, 2008)
This thesis formulates an estimation framework for Simultaneous Localization and Mapping (SLAM) that addresses the problem of scalability in large environments. We describe an estimation-theoretic algorithm that achieves ...
Modeling and frequency tracking of marine mammal whistle calls
(Massachusetts Institute of Technology, 2009)
Marine mammal whistle calls present an attractive medium for covert underwater communications. High quality models of the whistle calls are needed in order to synthesize natural-sounding whistles with embedded information. ...
Stochastic acoustic ray tracing with dynamically orthogonal equations
(Massachusetts Institute of Technology, 2020)
Developing accurate and computationally efficient models for ocean acoustics is inherently challenging due to several factors including the complex physical processes and the need to provide results on a large range of ...
Design considerations for engineering Autonomous Underwater Vehicles
(Massachusetts Institute of Technology, 2007)
Autonomous Underwater Vehicles (AUVs) have been established as a viable tool for Oceanographic Sciences. Being untethered and independent, AUVs fill the gap in Ocean Exploration left by the existing manned submersible and ...
Variable buoyancy system metric
(Massachusetts Institute of Technology, 2009)
Over the past 20 years, underwater vehicle technology has undergone drastic improvements, and vehicles are quickly gaining popularity as a tool for numerous oceanographic tasks. Systems used on the vehicle to alter buoyancy, ...
Signal absorption-based range estimator for undersea swarms
(Massachusetts Institute of Technology, 2020)
Robotic swarms are becoming increasingly complex on the surface and in air due to highspeed and reliable communication links, Global Positioning Satellites (GPS), and visual support to relative navigation. However, the ...
Automated open circuit scuba diver detection with low cost passive sonar and machine learning
(Massachusetts Institute of Technology, 2019)
This thesis evaluates automated open-circuit scuba diver detection using low-cost passive sonar and machine learning. Previous automated passive sonar scuba diver detection systems required matching the frequency of diver ...