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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.
321

Motion and wave load analyses of large offshore structures and special vessels in waves

Wu, Xiong-Jian January 1990 (has links)
Predictions of the environmental loading and induced motional and structural responses are among the most important aspects in the overall design process of offshore structures and ships. In this thesis, attention is focused on the wave loads and excited bodily motion responses of large offshore structures and special vessels. With the aim of improving the existing theoretical methods to provide techniques of theoretical effectiveness, computational efficiency, and engineering practicality in marine and offshore applications, the thesis concentrates upon describing fundamental and essential aspects in the physical phenomenon associated with wave-structure interactions and deriving new methods and techniques to analyse offshore structures and unconventional ships of practical interest. The total wave force arising from such a wave-structural interaction is assumed to be a simple superposition of the potential and the viscous flow force components. The linear potential forces are solved by the Green function integral equation whilst the viscous forces are estimated based on the Morison's damping formula. Forms of the Green function integral equation and the associated Green function are given systematically for various practical cases. The relevant two-dimensional versions are then derived by a transformation procedure. Techniques are developed to solve the integral equation numerically including the interior integral formulation and, in particular, to tackle the mathematical difficulties at irregular frequencies. In applying the integral equations to solve problems with various offshore structures and special vessels, some modified, improved or simplified methods are proposed. At first, simplified method is derived for predictions of the surge, sway and yaw motions of elongated bodies of full sectional geometry or structures with shallow draft. Then, a new shallow draft theory is described for both three- and two-dimensional cases with inclusion of the finite draft effect. Furthermore, a three-dimensional strip method is formulated where the end effects of the body are fully taken into account. Finally, an approximation to the horizontal mean drift forces of multi-column offshore structures are presented. Some new findings are also discussed including the multiple resonances occurring in the motions of multi-hulled marine structures due to the wave-body interaction, the mutual cancellation effect of the diffraction and the radiation forces arising from a full shaped slender body, and so on. Further to those verification studies for individual methods developed, more comprehensive example investigations are given related to two industrial applications. One is a derrick barge semi-submersible with zero forward speed; and the other, a SWATH ship with considerable speed. By correlation of all the proposed approaches with available analytical, numerical and experimental data, the thesis tries to demonstrate a principle that as long as principal physical aspects in the wave-structure interaction problem are properly treated, an appropriately modified or simplified method works, performs well and, sometimes, even better.
322

Kadomtsev-Petviashvili type differential systems : their symmetries and an application to solitary wave propagation in nonuniform channels

David, Daniel January 1987 (has links)
No description available.
323

Targeting of stones and identification of stone fragmentation in shock wave lithotripsy /

Owen, Neil R., January 2007 (has links)
Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (leaves 73-87).
324

Development and verification of a mathematical model to investigate the effects of earth-surface-based multipath reflections at a differential global positioning system ground reference site

Aloi, Daniel Nicholas. January 1999 (has links)
Thesis (Ph. D.)--Ohio University, August, 1999. / Title from PDF t.p.
325

H.F. radio wave attenuation in the ionosphere

George, Peter Leslie. January 1968 (has links) (PDF)
Thesis (M.Sc.)--University of Adelaide, Dept. of Physics, 1969. / Candidate's reply (16 leaves) in pocket.
326

Silicon-based laterally waveguide-coupled square microcavity channel add-drop filters /

Fong, Chung Yan. January 2004 (has links)
Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2004. / Includes bibliographical references (leaves 98-103). Also available in electronic version. Access restricted to campus users.
327

Axiomatic approach to radiation reaction of scalar point particles in curved spacetime /

Quinn, Theodore C. January 2000 (has links)
Thesis (Ph. D.)--University of Chicago, Dept. of Physics. / Includes bibliographical references. Also available on the Internet.
328

Quantum dynamics on adaptive grids the moving boundary truncation method /

Pettey, Lucas Richard, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.
329

Report on the Office of Naval Research Shallow Water Acoustics Workshop, April 24-26, 1991 /

Frisk, George V. January 1900 (has links)
"January 1992." / "Technical report." "Funding was provided by the Office of Naval Research through Contract no. N00014-91-J-1776." Includes bibliographical references (p. 7).
330

Report on the Office of Naval Research USA-China Conference on Shallow Water Acoustics, December 18-21, 1995

Chiu, Ching-Sang. Denner, Warren W. January 1997 (has links)
"January 1997." Thesis (Ph. D.)--Naval Postgraduate School, 1996. / "Prepared for: Office of Naval Research, Arlington, VA 22217-5660."

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