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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Interpretation of equatorial current meter data as internal waves

Blumenthal, Martin Benno January 1987 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric and Planetary Sciences, and Woods Hole Oceanographic Institution, 1987. / Bibliography: v. 2, leaves 376-381. / by Martin Benno Blumenthal. / Ph.D.
62

Fuel-cell propulsion for small manned submersibles.

Haddock, James Max January 1979 (has links)
Thesis (Ocean.E)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1979. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Includes bibliographical references. / Ocean.E
63

Identification of chemoautotrophic microorganisms from a diffuse flow hydrothermal vent at EPR 9° north using ¹³C DNA stable isotope probing and catalyzed activated reporter deposition-fluorescence in situ hybridization

Richberg, Kevin Patrick January 2010 (has links)
Thesis (S.M.)--Joint Program in Biological Oceanography (Massachusetts Institute of Technology, Dept. of Biology; and the Woods Hole Oceanographic Institution), 2010. / Cataloged from PDF version of thesis. / Includes bibliographical references (p. 47-54). / At deep-sea hydrothermal vents chemolithoautotrophic microbes mediate the transfer of geothermal chemical energy to higher trophic levels. To better understand these underlying processes and the organisms catalyzing them, this research used DNA Stable Isotope Probing (SIP) combined with Catalyzed Activated Reporter Deposition-Fluorescence in situ Hybridization (CARD-FISH) to identify the microorganisms chemoautotrophically supporting the food web at a diffuse flow hydrothermal vent. Both anaerobic and aerobic shipboard incubations containing various augmented electron donor and acceptor species showed that Epsilonproteobacteria were the dominant chemoautotrophs with greater than 70% of the cells counted within the first 24 hours. 13C DNA SIP identified unique organisms not previously characterized from low temperature diffuse flow venting: green sulfur bacteria (Chlorobi-like organisms) possibly utilizing photoautotrophy, aerobic Lutibacter litoralis-like organisms growing under anaerobic conditions, and Epsilonproteobacterial Thioreductor sp. at temperatures above maximum known tolerances. This research illustrates both the promise and pitfalls of the SIP technique applied to hydrothermal systems, concluding that timing of the incubation experiments is the critical step in eliminating undesired 13C labeling. These results set the stage for a more thorough future examination of diffuse flow microorganisms by presenting interesting questions that second generation experiments could be designed to answer. / by Kevin Patrick Richberg. / S.M.
64

Scale closure in upper ocean optical properties : from single particles to ocean color

Green, Rebecca E. (Rebecca Erin), 1972- January 2002 (has links)
Thesis (Ph.D.)--Joint Program in Biological Oceanography (Massachusetts Institute of Technology, Dept. of Biology, and the Woods Hole Oceanographic Institution), 2002. / Includes bibliographical references. / Predictions of chlorophyll concentration from satellite ocean color are an indicator of phytoplankton primary productivity, with implications for foodweb structure, fisheries, and the global carbon cycle. Current models describing the relationship between optical properties and chlorophyll do not account for much of the optical variability observed in natural waters, because of the presence of seawater constituents that do not covary with phytoplankton pigment concentration. In an attempt to better understand variability in these models, the contributions of seawater constituents to ocean optical properties were investigated. A combination of Mie theory and flow cytometry was used to determine the diameter, complex refractive index (n+n'i), and optical cross-sections of individual particles, based on a method developed in the laboratory using phytoplankton cultures. Individual particle measurements were used to interpret variability in concurrently measured bulk optical properties in New England continental shelf waters in two seasons. The summed contribution to scattering of individual particles in the size range of 0.1-50 Cpm accounted for approximately the entire scattering coefficient measured independently using bulk methods. In surface waters in both seasons, the large diameters and n' of eukaryotic phytoplankton caused them to be the main particle contributors to both absorption and scattering. Minerals were the main contributor to backscattering, bb, in the spring, whereas in the summer both minerals and detritus contributed to bb. Synechococcus and heterotrophic bacteria were less important optically, contributing <11% each to attenuation in either season. / (cont.) The role of seawater constituents in determining remote sensing reflectance, Rrs, was determined using radiative transfer theory. Seasonal differences in the spectral shape of Rrs were contributed to approximately equally by eukaryotic phytoplankton absorption, dissolved absorption, and non-phytoplankton bb. A higher inverse wavelength dependence of non-phytoplankton bb in the summer was caused by the contribution of small detritus, in contrast to larger minerals in the spring. Measurements of bb and Rrs were compared to values from bio-optical models based on chlorophyll concentration. Differences in measured and modeled bb and Rrs were caused by higher dissolved absorption and higher backscattering efficiencies and scattering by non-phytoplankton than were assumed by the model. / by Rebecca E. Green. / Ph.D.
65

Seasonal Variability of Water Mass Properties in Bass Strait: Three-dimensional oceanographic modelling studies

Sandery, Paul Anthony, paul.sandery@flinders.edu.au January 2007 (has links)
The climatology of the seasonal cycle of water mass variation and transformation in Bass Strait, south-eastern Australia, is studied using a high resolution three-dimensional sigma-coordinate hydrodynamic model coupled with data from observations and previous studies. Model forcing consists of the principal tidal constituents from the Australian National Tidal Centre and long-term monthly mean atmospheric forcing fields from NCEP reanalysis. The initial density field is established using temperature and salinity means and annual and semi-annual harmonics from the CARS2000 hydrographic atlas. This is also used to prescribe incoming water mass properties at model open-sea boundaries with seasonal variation. Far-field forcing is included with open-sea boundary parameterisation of residual sea-level representing both the South Australian Current and the East Australian Current. Lagrangian and Eulerian tracer methods are used to derive transport timescales, such as age, residence times and flushing times. These are used to examine and summarise model predictions and as a diagnostic tool in sensitivity studies. Currents, sea-level and water mass properties in the model compare favourably with previous studies and observations, despite limitations in the model and in the data used for comparison. The seasonal cycle, in model results, is characterised by formation of a shallow (< 20 m) saltier surface-layer in late spring to summer and subsequent downward mixing and erosion of the salinity field in autumn to winter with water mass from the west. This leaves behind water mass with positive age and salinity anomalies in areas of low flushing. In late winter-early spring most parts of this water mass leave the Strait interior. These areas are thought to be related to the source water of the Bass Strait Cascade. The residual circulation in all model experiments is shown to be related to seasonal-mean sea-level anomalies, arising from both barotropic and baroclinic adjustment, both in and surrounding the Strait.
66

Implementation and validation of a virtual buoy network for the island of Oahu utilizing nested third generation wind wave models /

Hansen, Demont. January 2005 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references (leaves 57-59). Also available via World Wide Web.
67

Studies to improve estimation of the electromagnetic bias in radar altimetry /

Smith, Justin Dewitt. January 1999 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Electrical and Computer Engineering, 1999. / Includes bibliographical references (p. 139-141).
68

The development of a deep-towed gravity meter, and its use in marine geophysical surveys of offshore Southern California and an airborn laser altimeter survey of Long Valley, California /

Ridgway, Jeffrey R., January 1997 (has links)
Thesis (Ph. D.)--University of California, San Diego, 1997. / Vita. Includes bibliographical references.
69

Implementing METOC transformation : applying autonomous agents /

Vorrath, Jonathan J. January 2004 (has links) (PDF)
Thesis (M.S. in Meteorology and Physical Oceanography)--Naval Postgraduate School, Sept. 2004. / Thesis Advisor(s): Carlyle Wash. Includes bibliographical references (p. 49). Also available online.
70

An analysis of Lemmings : a swarming approach to mine countermeasures in the VSW/SZ/BZ

Weber, Timothy R. January 1995 (has links) (PDF)
Thesis (M.S. in Mathematics) Naval Postgraduate School, December 1995. / "December 1995." Thesis advisor(s): Carlos Borges, Bard K. Mansager. Includes bibliographical references. Also available online.

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