Now showing items 600-619 of 982

    • Non-linear dynamic intertwining of rods with self-contact 

      Goyal, Sachin; Perkins, N. C.; Lee, Christopher L. (2007-10)
      Twisted marine cables on the sea floor can form highly contorted three-dimensional loops that resemble tangles. Such tangles or ‘hockles’ are topologically equivalent to the plectomenes that form in supercoiled DNA ...
    • Non-Rayleigh acoustic scattering characteristics of individual fish and zooplankton 

      Stanton, Timothy K.; Chu, Dezhang; Reeder, D. Benjamin (IEEE, 2004-04)
      It has long been known that the statistical properties of acoustic echoes from individual fish can have non-Rayleigh characteristics. The statistical properties of echoes from zooplankton are generally less understood. In ...
    • Non-Rayleigh scattering by a randomly oriented elongated scatterer 

      Bhatia, Saurav (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2012-08)
      The echo statistics of a randomly rough, randomly oriented prolate spheroid that is randomly located in a beampattern are investigated from physics-based principles both analytically and by Monte Carlo methods. This is ...
    • Nonlinear generation and loss of infragravity wave energy 

      Henderson, Stephen M.; Guza, R. T.; Elgar, Steve; Herbers, T. H. C.; Bowen, A. J. (American Geophysical Union, 2006-12-08)
      Nonlinear energy transfers with sea and swell (frequencies 0.05–0.40 Hz) were responsible for much of the generation and loss of infragravity wave energy (frequencies 0.005–0.050 Hz) observed under moderate- and low-energy ...
    • North Atlantic right whales (Eubalaena glacialis) ignore ships but respond to alerting stimuli 

      Nowacek, Douglas P.; Johnson, Mark P.; Tyack, Peter L. (Royal Society, 2003-12-03)
      North Atlantic right whales were extensively hunted during the whaling era and have not recovered. One of the primary factors inhibiting their recovery is anthropogenic mortality caused by ship strikes. To assess risk ...
    • The North Pacific Acoustic Laboratory deep-water acoustic propagation experiments in the Philippine Sea 

      Worcester, Peter F.; Dzieciuch, Matthew A.; Mercer, James A.; Andrew, Rex K.; Dushaw, Brian D.; Baggeroer, Arthur B.; Heaney, Kevin D.; D'Spain, Gerald L.; Colosi, John A.; Stephen, Ralph A.; Kemp, John N.; Howe, Bruce M.; Van Uffelen, Lora J.; Wage, Kathleen E. (Acoustical Society of America, 2013-10)
      A series of experiments conducted in the Philippine Sea during 2009–2011 investigated deep-water acoustic propagation and ambient noise in this oceanographically and geologically complex region: (i) the 2009 North Pacific ...
    • A note about Gaussian statistics on a sphere 

      Chave, Alan D. (Oxford University Press, 2015-07)
      The statistics of directional data on a sphere can be modelled either using the Fisher distribution that is conditioned on the magnitude being unity, in which case the sample space is confined to the unit sphere, or using ...
    • A novel trigger-based method for hydrothermal vents prospecting using an autonomous underwater robot 

      Ferri, Gabriele; Jakuba, Michael V.; Yoerger, Dana R. (2010-04)
      In this paper we address the problem of localizing active hydrothermal vents on the seafloor using an Autonomous Underwater Vehicle (AUV). The plumes emitted by hydrothermal vents are the result of thermal and chemical ...
    • Numerical and experimental analysis of initial water impact of an air-dropped REMUS AUV 

      Roe, Stephen Michael (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2005-02)
      The initial water impact of a free-falling object is primarily related to the fluid forces on the wetted surface of the object. The shape-dependent added-mass coefficients express the fluid forces integrated over the body, ...
    • Numerical modeling of an estuary : a comprehensive skill assessment 

      Warner, John C.; Geyer, W. Rockwell; Lerczak, James A. (American Geophysical Union, 2005-05-04)
      Numerical simulations of the Hudson River estuary using a terrain-following, three-dimensional model (Regional Ocean Modeling System, ROMS) are compared with an extensive set of timeseries and spatially resolved measurements ...
    • Numerical simulations of the flow and sediment transport regimes surrounding a short cylinder 

      Hatton, Kimberly A.; Foster, Diane L.; Traykovski, Peter A.; Smith, Heather D. (IEEE, 2007-01)
      The 3-D flow field and bed stress surrounding a short cylinder in response to combined wave and mean-flow forcing events is examined. Model simulations are performed with a 3-D nonhydrostatic computational fluid dynamics ...
    • The numerical synthesis and inversion of acoustic fields using the Hankel transform with application to the estimation of the plane wave reflection coefficient of the ocean bottom 

      Mook, Douglas Robert (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1983-01)
      The plane wave reflection coefficient is an important geometry independent mean of specifying the acoustic response of a horizontally stratified ocean bottom. It is an integral step in the inversion of acoustic field ...
    • Oblique internal hydraulic jumps at a stratified estuary mouth 

      Honegger, David A.; Haller, Merrick C.; Geyer, W. Rockwell; Farquharson, Gordon (American Meteorological Society, 2017-01-04)
      Observations and analyses of two tidally recurring, oblique, internal hydraulic jumps at a stratified estuary mouth (Columbia River, Oregon/Washington) are presented. These hydraulic features have not previously been studied ...
    • Observation and inversion of seismo-acoustic waves in a complex Artic ice environment 

      Miller, Bruce E. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1990-09)
      The propagation of low frequency seismo-acoustic waves in the Arctic Ocean ice canopy is examined through the analysis of hydrophone and geophone data sets collected in 1987 at an ice camp designated PRUDEX in the Beaufort ...
    • Observationally constrained modeling of sound in curved ocean internal waves: Examination of deep ducting and surface ducting at short range 

      Duda, Timothy F.; Lin, Ying-Tsong; Reeder, D. Benjamin (Acoustical Society of America, 2011-09)
      A study of 400 Hz sound focusing and ducting effects in a packet of curved nonlinear internal waves in shallow water is presented. Sound propagation roughly along the crests of the waves is simulated with a three-dimensional ...
    • Observations and a model of undertow over the inner continental shelf 

      Lentz, Steven J.; Fewings, Melanie R.; Howd, Peter A.; Fredericks, Janet J.; Hathaway, Kent (American Meteorological Society, 2008-11)
      Onshore volume transport (Stokes drift) due to surface gravity waves propagating toward the beach can result in a compensating Eulerian offshore flow in the surf zone referred to as undertow. Observed offshore flows indicate ...
    • Observations and model simulations of wave-current interaction on the inner shelf 

      Hopkins, Julia; Elgar, Steve; Raubenheimer, Britt (John Wiley & Sons, 2016-01-10)
      Wave directions and mean currents observed for two 1 month long periods in 7 and 2 m water depths along 11 km of the southern shoreline of Martha's Vineyard, MA, have strong tidal modulations. Wave directions are modulated ...
    • Observations and modeling of a tidal inlet dye tracer plume 

      Feddersen, Falk; Olabarrieta, Maitane; Guza, R. T.; Winters, Dylan; Raubenheimer, Britt; Elgar, Steve (John Wiley & Sons, 2016-10-24)
      A 9 km long tracer plume was created by continuously releasing Rhodamine WT dye for 2.2 h during ebb tide within the southern edge of the main tidal channel at New River Inlet, NC on 7 May 2012, with highly obliquely ...
    • Observations and modeling of sand transport in a wave dominated environment 

      Traykovski, Peter A. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1998-05)
      Observations of bedforms, suspended sediment and water velocities were used to examine sediment transport processes at the sandy LE0-15 site located off the New Jersey coast. The bedforms were observed during storms using ...
    • Observations and modeling of wave-acceleration-induced sediment transport in the surfzone 

      Hoefel, Fernanda Gemael (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2004-02)
      Onshore sediment transport and sandbar migration are important to the morphological evolution of beaches, but are not understood well. Here, a new model that accounts for accelerations of wave-orbital velocities predicts ...