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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.
261

Characterization of fracture roughness and its role in modelling the stress-flow behaviour of fractured rock /

Briggins, David Rodney, January 1992 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland. / Typescript. Bibliography: leaves 128-136. Also available online.
262

Deformation and fracture of polycrystalline lithium fluoride

Scott, William Doane. January 1961 (has links)
Thesis (Ph. D. in Engineering)--University of California, Berkeley, Sept. 1961. / Bibliography: l. 74-78.
263

Nonlinear dynamics and contact fracture mechanics of high frequency percussive drilling

Ajibose, Olusegun K. January 2009 (has links)
Thesis (Ph.D.)--Aberdeen University, 2009. / Title from web page (viewed on Mar. 26, 2010). Includes bibliographical references.
264

Towards a generative model of natural motion /

Liu, Cheng-Yun Karen, January 2005 (has links)
Thesis (Ph. D.)--University of Washington, 2005. / Vita. Includes bibliographical references (p. 117-124).
265

The effect of rate of shear on the residual strength of soil

Tika, Theodora Michael. January 1989 (has links)
Thesis (doctoral)--University of London, 1989.
266

Governing parameters for stress-dependent soil-water characteristics, conjunctive flow and slope stability /

Ho, Mei Yung. January 2007 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2007. / Includes bibliographical references (leaves 175-183). Also available in electronic version.
267

Discrete element modeling of rock fracture behavior fracture toughness and time-dependent fracture growth /

Park, Namsu, January 1900 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.
268

Mathematical modelling of droplets climbing an oscillating plane

Bradshaw, Joel January 2016 (has links)
Recent experiments [P. Brunet, J. Eggers, and R. Deegan, Phys. Rev. Lett. 99, 114501 (2007)] have shown that a liquid droplet on an inclined plane can be made to move uphill by sufficiently strong, vertical oscillations. In order to investigate this counterintuitive phenomenon we will derive three different models that qualitatively reproduce the main features of the experiment. For the first model the liquid's inertia and viscosity are assumed negligible, so that the motion of the droplet is dominated by the applied acceleration due to the oscillation of the plate, gravity and surface tension and that the droplet is thin. We explain how the leading order motion of the droplet can be separated into a spreading mode and a swaying mode. For a linear contact line law, the maximum rise velocity occurs when the frequencies of oscillation of the two modes are in phase. We show that, both with and without contact angle hysteresis, the droplet can climb uphill and also that, for certain contact line laws, the motion of the droplet can produce footprints similar to experimental results. We show that if the two modes are out of phase when there is no contact angle hysteresis, the inclusion of hysteresis can force them into phase. This in turn increases the rise velocity of the droplet and can, in some cases, cause a sliding droplet to climb. For the second model we use a two-dimensional flow where the Reynolds number is assumed large enough for viscosity to be neglected. We show that the leading order motion of the droplet can be separated into the same two modes and the net motion of the droplet is an oscillatory function of the frequency. For increasingly non-wetting droplets we discover that the rise velocity begins to oscillate very rapidly as a function of the static contact angle. What we also discover is that the change in the free surface of the droplet is actually a wave travelling travelling across the droplet, and the amount of modes present coincide with the rapid change in the rise velocity. Using a cubic contact line law and contact angle hysteresis we observe a droplet that can climb uphill for parameter values similar to that of the experiment. With the addition of a time dependent term within the contact line law we show that it is possible to obtain a multi-valued relationship between the velocity of the contact line and the respective contact angles, reproducing experimental observations seen for unsteady, moving contact lines. For the third model we again assume that the liquid's viscosity is negligible, similar to model 2, only now for a three-dimensional, thin droplet. For very small amplitudes the motion of the droplet is a combination of a swaying mode and a spreading mode that interact causing a net motion of the droplet. This motion is found to be an oscillatory function of the driving frequency and the magnitude of the peak rise velocity is proportional to one over the frequency squared. By examining the velocity of the centre of the droplet and the displacement of the contact line we see that the absolute maximums of both of these, over one period of oscillation, contain natural frequencies, which are evenly spaced with respect to the square root of the frequency of the oscillation.
269

A Study of Modifications to Quantum Mechanics

Lewis, Zachary 05 March 2013 (has links)
In this work, the consequences of several modifications to quantum mechanics are examined. These modifications, motivated by string theory, fall into two categories: ones in which the canonical commutation relations between position and momentum are deformed and ones in which the space of states used are vector spaces over Galois fields instead of complex Hilbert spaces. The particular deformation of the canonical commutation relations used leads to a minimum value of the uncertainty in position which is interpreted as a minimum length scale. Both harmonic and anharmonic oscillators are studied in this framework with normalizable, positive energy eigenstates found in both cases. The quantum uncertainty relations and classical counterparts to these states are discussed. Creating modified quantum theories by replacing the Hilbert spaces of canonical quantum mechanics with vector spaces defined over several finite, Galois fields is accomplished. Correlation functions are calculated in these theories and the maximum values are shown to not behave as would be expected by the standard, Bell-like, bounding inequality theorems. The interpretations and implications of these theories are discussed. / Ph. D.
270

Drag Coefficients for Magnetically Accelerated Spheres

Liang, Jann-Wuu 01 August 1966 (has links)
The objective of this study was to determine the correlation of the drag coefficient of an accelerating sphere in the liquid medium over a range of Reynolds number from 0.1 to 100, 000. A magnetic accelerator was used to obtain an acceleration for the sphere, the data was recorded using a photograph and a digital computer was used to reduce the data.

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