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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

On the dispersion relations of internal waves of the ocean

Jordon, Joseph Bell. January 1981 (has links)
Thesis (M.S.)--University of California, Santa Cruz, 1981. / Typescript. Includes bibliographical references.
62

The kinematics of breaking waves in the surf zone

Olsen, Alfred James. January 1977 (has links)
Thesis (M.S.)--Naval Postgraduate School, 1977. / Includes bibliographical references (leaves 74-75).
63

Interpretation of equatorial current meter data as internal waves

Blumenthal, Martin Benno. January 1900 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1987. / "January 1987." Includes bibliographical references (p. 376-381).
64

Breaking wave turbulence in the surf zone /

Sweeny, Margaret E. January 2005 (has links) (PDF)
Thesis (M.S. in Applied Science (Physical Oceanography))--Naval Postgraduate School, June 2005. / Thesis Advisor(s): Timothy P. Stanton. Includes bibliographical references (p. 51). Also available online.
65

The effect of breaking waves on a coupled model of wind and ocean surface waves /

Kukulka, Tobias. January 2006 (has links)
Thesis (Ph. D.)--University of Rhode Island, 2006. / Typescript. Includes bibliographical references (leaves 178-183).
66

Estimation of planetary wave parameters from the data of the 1981 Ocean Acoustic Tomography Experiment /

Chiu, Ching-Sang. January 1900 (has links)
Thesis (D.S.)--Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1985. / "October 1985." Includes bibliographical references (p. 251-255).
67

Time-domain solution for second-order wave diffraction

Cheung, Kwok Fa January 1991 (has links)
A numerical method based on potential flow theory is developed for simulating transient, second-order interactions of ocean waves with large fixed bodies of arbitrary shape in two and three dimensions. The physical problem is represented by a mathematical model composed of a fluid domain bounded by the body surface, the still water surface, the seabed, and a control surface truncating the infinite fluid region. The nonlinear free surface boundary conditions defined on the instantaneous free surface are expanded about the still water level by a Stokes expansion procedure. The flow potential to second order is thereby defined with respect to a time-independent boundary which includes the still water surface, and its solution involves a numerical discretization of an integral equation. With the potential separated into incident and scattered components, the Sommerfeld radiation condition applied to the scattered potential is modified to incorporate a time-dependent celerity to account for the transient and second-order effects. The free surface boundary conditions and the radiation condition are then satisfied to second order by a numerical integration in time. An alternative second-order solution is derived based on a different expansion procedure in which the nonlinear free surface boundary conditions and an integral equation defined on the instantaneous free surface are both expanded by a Taylor series, and terms up to second order are retained. The two approaches give rise to identical first-order problems, but give rise to second-order problems which are apparently different. The discrepancy arises from the second-order integral equation in which additional second-order terms are retained. The physical interpretations and limitations of these terms are explored and their effects on the evaluations of wave forces are assessed. Applications of the present method are made to studies of regular wave diffraction around a fully submerged and a semi-submerged circular cylinder in two dimensions, and around a bottom-mounted surface-piercing circular cylinder in three dimensions. The stability and numerical accuracy of the proposed solution and the treatment of the radiation condition to second order are examined. Comparisons of computed wave forces and runup are made with previous theoretical and experimental results and these indicate favourable agreement. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate
68

Microscale pressure fluctuations measured within the lower atmospheric boundary layer

Elliott, James Arthur January 1970 (has links)
An instrument was developed to measure the static pressure fluctuations within the turbulent flow of the atmospheric boundary layer. This instrument was used to measure some of the properties of pressure fluctuations over a flat boundary and over water waves and has provided the first reliable pressure data within a turbulent boundary layer. For all observations over a flat boundary the root-mean-square pressure produced by the boundary layer turbulence was about 2.6 times the mean stress. The spectra had a power law behaviour with a mean slope of -1.7 for scales above the peak of the vertical velocity spectrum. Pressure fluctuations were approximately spherical in shape, and propagated downstream at a rate equal to the 'local' mean wind. Above the boundary, the large scale pressure fluctuations were approximately in phase with the downstream velocity fluctuations; at small scales there was a large phase difference (≃135°). These phase differences were interpreted to be the result of the large pressure producing scales interacting with the earth's surface, while the small scales were 'free' of the surface. Pressure forces resulted in an energy flux out of the downstream velocity fluctuations of about 0.45 of the total energy source for the turbulence within the band of 0.05 < kz < 20. The pressure term in the net energy budget was found to be about 1/10 of the energy feeding term. Pressure measurements near wind generated waves showed a large spectral hump at the wave frequencies. The amplitude of this hump increased, and its vertical rate of decay decreased, as the mean wind speed increased. The phase difference between pressure and waves during active generation was found to be about 135°, pressure lagging waves. This did not change vertically. / Science, Faculty of / Physics and Astronomy, Department of / Graduate
69

The wave field on a shelf resulting from point source generation, with application to tsunamis

King, David Randall January 1978 (has links)
Studies were made to determine the wave field of long surface gravity waves generated on a shelf by a localized source, such as might occur in tsunami generation. Beth analytical and experimental aspects of the problem are investigated. An analytical model is constructed, which examines the field of small amplitude shallow water waves propagating on a shelf of uniform depth. The shelf region is separated from a deep water region of uniform depth by a linear vertical step. The problem is solved on a rotating coordinate system, although the more precise results are obtained for wave frequencies much greater than the inertial frequency for the case of non-rotation. Both exact solutions and asymptotic solutions in the far-field are found for point source excitation. The case of zero-rotation is investigated for both time-harmonic and impulse excitation. The experimental model examines the field of shallow water waves generated under conditions chosen to simulate the analytical model for the case of non-rotation. The resulting field is composed of cylindrical direct and reflected waves and of a plane lateral wave which arises under conditions of total reflection. Have speeds are found which are in agreement with those predicted by ray theory and geometrical optics. Wave amplitudes of the direct and reflected waves behave as cylindrical waves with frictional damping. The lateral wave amplitude decays in accordance with the -1.5 power of the ray optics pathlength of the lateral wave in the deep water, with damping due to friction. Agreement of theory with observation is overall very good. The results are applied to the problem of tsunami generation on a shelf under simple geometrical conditions. Arrival-times of the various field constituents at various points along the shoreline (the inner edge of the shelf) are calculated and the lead time of the lateral wave arrival over the direct wave is determined. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Unknown
70

Low-frequency vorticity waves over strong topography

Gratton, Yves January 1983 (has links)
This thesis addresses the general problem of vorticity waves propagating over steeply sloping topography, in the presence of stratification and rotation. From the inviscid unforced long-wave equations for a two-layer fluid on an f-plane, it is shown that, as long as the ratio of the upper to lower layer depths is small, semi-enclosed and enclosed basins can sustain low-frequency, short scale, surface-intensified motions. Simple analytical solutions are to be found only if the upper to lower layer depths ratio is small. Then, we obtain a set of equations which describes a barotropic wave which forces a baroclinic response through topographic coupling. Two bottom profiles are considered: linear and parabolic. Solutions are found with and without the small slope approximation. It is shown that the small slope approximation underestimates all the parameters of low-frequency topographic waves, even when the slope is small. The theory is compared with observations from the Strait of Georgia and with a numerical model of the Saint Lawrence estuary. It is found that, for bathymetric profiles similar to those of the Strait of Georgia (linear) and the Saint Lawrence (parabolic), bur model provides a better fit to the topography, leads to surface-intensified motions and produces cross-channel velocities very similar to those observed in situ. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

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