Now showing items 497-516 of 982

    • The load/deflection behavior of pretensioned cable/pulley transmission mechanisms 

      Snow, Edward R. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1993-12)
      Mechanical transmission mechanisms enable a designer to match the abilities (e .g. velocity, torque capacity) of an actuator to the needs of an application. Unfortunately the mechanical limitations of the transmission ...
    • LOCOMOOR : a LOw-COst MOORing for the measurement of internal solitary waves 

      Lord, Jeffrey; Irish, James D.; Duda, Timothy F.; Kemp, John N. (2000-05-09)
      In order to supplement the ASIAEX field effort to measure the temporal and spatial structure of the internal solitary wave field in relationship to acoustic propagation and scattering studies, an array of low-cost ...
    • Long distance passive localization of vocalizing sei whales using an acoustic normal mode approach 

      Newhall, Arthur E.; Lin, Ying-Tsong; Lynch, James F.; Baumgartner, Mark F.; Gawarkiewicz, Glen G. (Acoustical Society of America, 2012-02)
      During a 2 day period in mid-September 2006, more than 200, unconfirmed but identifiable, sei whale (Balaenoptera borealis) calls were collected as incidental data during a multidisciplinary oceanography and acoustics ...
    • Long-baseline acoustic navigation for under-ice autonomous underwater vehicle operations 

      Jakuba, Michael V.; Roman, Christopher N.; Singh, Hanumant; Murphy, Christopher A.; Kunz, Clayton G.; Willis, Claire; Sato, Taichi; Sohn, Robert A. (2008-05-19)
      The recent Arctic GAkkel Vents Expedition (AGAVE) to the Arctic Ocean’s Gakkel Ridge (July/August 2007) aboard the Swedish ice-breaker I/B Oden employed autonomous underwater vehicles (AUVs) for water-column and ocean ...
    • Long-path quantum cascade laser–based sensor for methane measurements 

      Michel, Anna P. M.; Miller, David J.; Sun, Kang; Tao, Lei; Stanton, Levi; Zondlo, Mark A. (American Meteorological Society, 2016-11-01)
      A long-path methane (CH4) sensor was developed and field deployed using an 8-μm quantum cascade laser. The high optical power (40 mW) of the laser allowed for path-integrated measurements of ambient CH4 at total pathlengths ...
    • Loose-tube neutral tether fiber optic termination procedure 

      Bowen, Martin F. (Woods Hole Oceanographic Institution, 2001-06)
      Neutral tethers for unmanned underwater vehicles may contain a bundle of single-mode, optical fibers that are protected inside flexible stainless steel tubing. To date the author knows of no commercially available systems ...
    • Lossy compression and real-time geovisualization for ultra-low bandwidth telemetry from untethered underwater vehicles 

      Murphy, Christopher A. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2008-09)
      Oceanographic applications of robotics are as varied as the undersea environment itself. As underwater robotics moves toward the study of dynamic processes with multiple vehicles, there is an increasing need to distill ...
    • Low complexity lossless compression of underwater sound recordings 

      Johnson, Mark P.; Partan, James W.; Hurst, Thomas P. (Acoustical Society of America, 2013-03)
      Autonomous listening devices are increasingly used to study vocal aquatic animals, and there is a constant need to record longer or with greater bandwidth, requiring efficient use of memory and battery power. Real-time ...
    • Low-frequency bottom backscattering data analysis using multiple constraints beamforming 

      Li, Dan (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1995-05)
      The data analysis of a deep-sea bottom backscattering experiment, carried out over a sediment pond on the western flank of the Mid-Atlantic Ridge in July 1993 with a 250- 650 Hz chirp source and a vertical receiving array ...
    • Low-frequency broadband sound source localization using an adaptive normal mode back-propagation approach in a shallow-water ocean 

      Lin, Ying-Tsong; Newhall, Arthur E.; Lynch, James F. (Acoustical Society of America, 2012-02)
      A variety of localization methods with normal mode theory have been established for localizing low frequency (below a few hundred Hz), broadband signals in a shallow water environment. Gauss-Markov inverse theory is employed ...
    • Magnetotelluric data, stable distributions and impropriety: an existential combination 

      Chave, Alan D. (Oxford University Press, 2014-05-30)
      The robust statistical model of a Gaussian core contaminated by outlying data that underlies robust estimation of the magnetotelluric (MT) response function has been re-examined. The residuals from robust estimators are ...
    • Maintaining precision calibrations with optimal copper spheres 

      Foote, Kenneth G. (Acoustical Society of America, 1983-03)
      Effects of variations in quantities influencing the backscattering cross sections of solid elastic spheres are studied through a particular case. This is that of the 60‐mm‐diam copper sphere, which is being used worldwide ...
    • Mantle dynamics beneath the East Pacific Rise at 17°S : insights from the Mantle Electromagnetic and Tomography (MELT) experiment 

      Baba, Kiyoshi; Chave, Alan D.; Evans, Rob L.; Hirth, Greg; Mackie, Randall L. (American Geophysical Union, 2006-02-17)
      The electromagnetic data from the Mantle Electromagnetic and Tomography (MELT) experiment are inverted for a two-dimensional transversely anisotropic conductivity structure that incorporates a correction for three-dimensional ...
    • Map building fusing acoustic and visual information using autonomous underwater vehicles 

      Kunz, Clayton G.; Singh, Hanumant (2012-10)
      We present a system for automatically building 3-D maps of underwater terrain fusing visual data from a single camera with range data from multibeam sonar. The six-degree of freedom location of the camera relative to the ...
    • Mapping multiple gas/odor sources in an uncontrolled indoor environment using a Bayesian occupancy grid mapping based method 

      Ferri, Gabriele; Jakuba, Michael V.; Mondini, Alessio; Mattoli, Virgilio; Mazzolai, Barbara; Yoerger, Dana R.; Dario, Paolo (2011-06)
      In this paper we address the problem of autonomously localizing multiple gas/odor sources in an indoor environment without a strong airflow. To do this, a robot iteratively creates an occupancy grid map. The produced map ...
    • Marine animal sound classification 

      Fristrup, Kurt M.; Watkins, William A. (Woods Hole Oceanographic Institution, 1993-10)
      Software was developed to measure characteristics of marine animal sounds (AcouStat). These measurements proved effective for classifying sounds in several contexts: identifying species, quantifying the repertoire of a ...
    • Mass coral mortality under local amplification of 2°C ocean warming 

      DeCarlo, Thomas M.; Cohen, Anne L.; Wong, George T. F.; Davis, Kristen A.; Lohmann, George P.; Soong, Keryea (Nature Publishing Group, 2017-03-23)
      A 2°C increase in global temperature above pre-industrial levels is considered a reasonable target for avoiding the most devastating impacts of anthropogenic climate change. In June 2015, sea surface temperature (SST) of ...
    • A matched field processing approach to long range acoustic navigation 

      Deffenbaugh, Max (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1994-02)
      This thesis presents the design and simulation of an acoustic listen-only navigation system for use in a time-varying high-multipath environment. The system uses a ray tracing model of sound propagation in a horizontally ...
    • Maximizing AUV slow speed performance 

      LeBas, Phillip J. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1997-09)
      A review of the Odyssey IIB autonomous underwater vehicle shows that energy costs associated with vehicle controls can be reduced and operational flexibility improved with relatively simple, low cost improvements. Because ...
    • Maximum likelihood time-domain beamforming using simulated annealing 

      Xu, Kevin (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1999-09)
      An algorithm is developed for underwater acoustic signal processing with an array of hydrophones. With various acoustic signals coming from different directions, the maximum likelihood approach is used to estimate the ...