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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.
21

Modeling ice streams /

Sargent, Aitbala. January 2009 (has links)
Thesis (Ph.D.) in Computer Science--University of Maine, 2009. / Includes vita. Includes bibliographical references (leaves 127-135).
22

New techniques for the investigation of deformation mechanisms in flow of fine-grained ice Ih /

McDaniel, Shannon M. January 2005 (has links)
Thesis (Ph. D.)--University of Washington, 2005. / On t.p. "h" is subscript. Vita. Includes bibliographical references (leaves 113-125).
23

Transpolar sea ice drift in the vicinity of the Yermak Plateau as observed by ARCTEMIZ 86 buoys /

Hoffman, Paul J. January 1990 (has links) (PDF)
Thesis (M.S. in Meteorology and Physical Oceanography)--Naval Postgraduate School, March 1990. / Thesis Advisor(s): Gascard, Jean-Claude. Second Reader: Bourke, Robert H. "March 1990." Description based on signature page August 25, 2009. DTIC Descriptor(s): Sea Ice, Tidal Currents, Ocean Tides, Optimization, Ocean Waves, Morphology, Motion, Theses, Vortices, Drift, Surface Properties, Resonance, Convergence, Trajectories, Ocean Bottom Topography, Currents, Diurnal Variations, Grinding, Buoys, Arctic Ocean, Polar Regions, Plateaus, Velocity, Stations. Author(s) subject terms: Transpolar Drift, Sea Ice, ARCTEMIZ 86, Yermak Plateau, Diurnal Tidal Currents. Includes bibliographical references (p. 88-89). Also available online.
24

A Theoretical and Experimental Study of the Evolution of Surface Ice

Unduche, Fisaha Solomon 24 January 2012 (has links)
The theory of the formation of surface ice is not fully understood, yet its presence on water surface affects the operation of many different kinds of hydraulic structures. It is known that when the water surface temperature reaches supercooling ice particles are formed at the water surface. If the intensity of turbulence is low these ice particles will be suspended on the surface forming a surface ice. Herein, an experimental study that incorporates the effect of depth, velocity, roughness and air temperature is carried out in a counter-rotating flume to investigate the formation of surface ice in relation to these parameters. The experimental result is supported by a mathematical model based on the theory of formation of surface ice. A mathematical model is developed based on a comprehensive theory and is solved using Matlab. The mathematical model integrates the effect of the heat balance on the water surface with the degree of turbulent mixing and the rate of growth of surface ice. The two calibrating parameters for the model are the magnitude of the initial seeding and the surface heat loss coefficient. The developed mathematical model is calibrated for the different types of surface ice formations for the data obtained from the experiment. The experimental analysis shows that there are four main types of surface ice formations and their formation is mainly dependent on the degree of turbulence. It is also found that the types of these ice formations are dependent on the minimum supercooling temperature at an average depth. Moreover, it is demonstrated that skim ice particles are those ice particles that nucleate on the water surface during low to medium turbulent intensities and can have four different types of shapes, namely needle shapes, finger shapes, hexagonal shapes and irregular shapes. The sizes and relative quantities of these ice particles on the water surface are also dependent on the degree of turbulence.
25

A Theoretical and Experimental Study of the Evolution of Surface Ice

Unduche, Fisaha Solomon 24 January 2012 (has links)
The theory of the formation of surface ice is not fully understood, yet its presence on water surface affects the operation of many different kinds of hydraulic structures. It is known that when the water surface temperature reaches supercooling ice particles are formed at the water surface. If the intensity of turbulence is low these ice particles will be suspended on the surface forming a surface ice. Herein, an experimental study that incorporates the effect of depth, velocity, roughness and air temperature is carried out in a counter-rotating flume to investigate the formation of surface ice in relation to these parameters. The experimental result is supported by a mathematical model based on the theory of formation of surface ice. A mathematical model is developed based on a comprehensive theory and is solved using Matlab. The mathematical model integrates the effect of the heat balance on the water surface with the degree of turbulent mixing and the rate of growth of surface ice. The two calibrating parameters for the model are the magnitude of the initial seeding and the surface heat loss coefficient. The developed mathematical model is calibrated for the different types of surface ice formations for the data obtained from the experiment. The experimental analysis shows that there are four main types of surface ice formations and their formation is mainly dependent on the degree of turbulence. It is also found that the types of these ice formations are dependent on the minimum supercooling temperature at an average depth. Moreover, it is demonstrated that skim ice particles are those ice particles that nucleate on the water surface during low to medium turbulent intensities and can have four different types of shapes, namely needle shapes, finger shapes, hexagonal shapes and irregular shapes. The sizes and relative quantities of these ice particles on the water surface are also dependent on the degree of turbulence.
26

Determination of sea ice surface elevation with laser and radar altimetry and comparison with ice thickness data sets in the Arctic and Antarctic = Bestimmung der Oberflächenhöhe von Meereis mit Laser- und Radaraltimetrie und Vergleich mit Eisdickendatensätzen in der Arktis und Antarktis /

Göbell, Sibylle. January 2007 (has links)
Univ., Diss.--Bremen, 2007.
27

Helicopter electromagnetic sea ice thickness estimation : an induction method in the centimetre scale = Meereisdickenbestimmung mittels Hubschrauberelektromagnetik : ein Induktionsverfahren im Zentimeterbereich /

Pfaffling, Andreas. January 2007 (has links)
Univ., Diss.--Bremen, 2006. / Enth. außerdem 4 Papers.
28

The flow history of Siple Dome and Ice Streams C and D, West Antarctica : inferences from geophysical measurements and ice flow models /

Nereson, Nadine A. January 1998 (has links)
Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (p. [182]-192).
29

P-wave anisotropy in the high polar ice of East Antarctica

Blankenship, Donald D. January 1982 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1982. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 106-110).
30

The design and construction of an under ice vehicle

Hosig, Dale Nicholas. January 1960 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1960. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaf 58).

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