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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.
1

Experimental evaluation of mechanical anisotropy in the Waterloo quartzite

Ren, Nae-kan. January 1979 (has links)
Thesis (M.S.)--University of Wisconsin--Madison. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 110-115).
2

Disk ray theory in transversely isotropic media

Yedlin, Mathew Jacob January 1978 (has links)
The first motion approximation has been used to calculate synthetic seisnograms in transversely isotropic, linear, elastic media. To achieve this end the equations of motion have been solved in a geometrical optics regime. Formally, this has been accomplished by the use of asymptotic propagator matrices. This formalism is important, since the phase of the JWKB reflection coefficient can be easily calculated by consideration of the radiation condition. Calculation of this reflection coefficient has shown that the turning point behaviour is identical to that obtained for an isotropic medium. The similarity of the turning point behaviour is a direct consequence of the physical result that at a turning point the phase and group velocities are in the same direction. To understand the results of the first motion approximation applied to a simple upper mantle model, it is first necessary to understand the basic physics of transversely isotropic media. This has been achieved by examination of the dispersion relation arising from Newton*s Laws for an elastic solid. From the dispersion relation, it has been demonstrated how the Green's Function can be constructed using elementary projective geometry. Subsequently, the nature of the Green's Function has been analyzed. The analysis of the Green's Function (wave surface) is important because it facilitates comprehension of any dynamical results. The synthetic seismograms were calculated using ray parameter versus distance curves. These curves were obtained by integration of the ray equations derived form the dispersion relations. A Gaussian-Kantorovich method was utilized to perform the required integration. This hybrid integration technique proved to be extremely fast and accurate. When the resulting p-delta curve was used to calculate the synthetic seismogram, the main effect of the anisotropic model considered was a kinematic one - the main arrivals were earlier than those for an isotropic model. / Science, Faculty of / Physics and Astronomy, Department of / Graduate
3

Muon detector array to discriminate gamma-ray eas at mountainaltitude

梁淦章, Leung, Kam-cheung. January 1995 (has links)
published_or_final_version / Physics / Master / Master of Philosophy
4

Core-mantle boundary heterogeneity

Restivo, Andrea January 2001 (has links)
No description available.
5

Microwave spectroscopic studies of cobalt chromium thin films

Jackson, Matthew January 1997 (has links)
No description available.
6

Target tracking onboard an autonomous underwater vehicle: determining optimal towed array heading in an anisotropic noise field

Parra-Orlandoni, Maria Alejandra. 09 1900 (has links)
In order to overcome the challenges that an anisotropic noise field poses for underwater target tracking, we conduct an onboard estimation of the horizontal noise directionality in the real-time processing suite of an autonomous underwater vehicle (AUV) towing a horizontal line array. The estimation of the noise directionality is a precursor to another adaptive behavior: optimizing tracking capability of a towed array by choosing a particular heading that minimizes the detection level in the target's direction. In each distinct simulated anisotropic noise field, the AUV successfully calculates the optimal towed array headings based on the real-time estimation of the horizontal noise directionality. The findings reveal a clear advantage over the conventional broadside beam tracking method, with some limitations due predominantly to the noise field itself. / Contract number: N62271-97-G-0026
7

Dynamic mechanical anisotropy of polyethylene terephthalate.

January 1975 (has links)
Tsui Sai Ming. / Thesis (M.Phil.)--Chinese University of Hong Kong. / Bibliography: leaves i-ii.
8

Step induced magnetic anisptropy of Fe/W(100) /

Mireles, Hector Córdova, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 112-115). Available also in a digital version from Dissertation Abstracts.
9

Synthetic approaches to one-dimensional nanostructures /

Mayers, Brian T. January 2003 (has links)
Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (leaves 182-201).
10

Multiscale representation of polycrystalline inelasticity

McGinty, Robert Davis 08 1900 (has links)
No description available.

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