by Tam Chi Yung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 66-67). / by Tam Chi Yung. / Contents --- p.i / List of Figures --- p.iii / Acknowledgement --- p.iv / Abstract --- p.v / Chapter Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Open systems and quasinormal modes --- p.1 / Chapter 1.2 --- Gravitational waves --- p.3 / Chapter Chapter 2. --- Green's Function Formalism --- p.6 / Chapter 2.1 --- Introduction --- p.6 / Chapter 2.2 --- Constructing the Green's function --- p.7 / Chapter 2.3 --- The norm --- p.9 / Chapter 2.4 --- Completeness --- p.11 / Chapter Chapter 3. --- Potentials With No Tail --- p.13 / Chapter 3.1 --- Introduction --- p.13 / Chapter 3.2 --- Completeness --- p.14 / Chapter 3.2.1 --- Proof --- p.14 / Chapter 3.2.2 --- Examples --- p.16 / Chapter 3.3 --- The two-component approach --- p.20 / Chapter 3.3.1 --- Formalism --- p.21 / Chapter 3.3.2 --- Comparison of different expansion schemes --- p.23 / Chapter 3.3.3 --- Linear Space --- p.29 / Chapter 3.4 --- Perturbation theory --- p.31 / Chapter 3.4.1 --- Formalism --- p.31 / Chapter 3.4.2 --- Examples --- p.33 / Chapter 3.5 --- Conclusion --- p.35 / Chapter Chapter 4. --- Potentials With Exponential Tails --- p.36 / Chapter 4.1 --- Introduction --- p.36 / Chapter 4.2 --- Single exponential tail --- p.37 / Chapter 4.3 --- Asymptotics of QNM's --- p.40 / Chapter 4.4 --- The Born series --- p.43 / Chapter 4.5 --- Poschl-Teller potential --- p.44 / Chapter 4.5.1 --- Analytic solutions --- p.44 / Chapter 4.5.2 --- The norm --- p.46 / Chapter 4.6 --- The problem of cut-off --- p.48 / Chapter 4.7 --- An effective numerical scheme --- p.49 / Chapter 4.8 --- Conclusion --- p.53 / Chapter Chapter 5. --- Logarithmic Perturbation --- p.54 / Chapter 5.1 --- Introduction --- p.54 / Chapter 5.2 --- Formalism --- p.54 / Chapter 5.3 --- Examples --- p.57 / Chapter 5.4 --- Conclusion --- p.59 / Chapter Chapter 6. --- Conclusion --- p.60 / Appendix A. Asymptotic behaviour of the Green's function --- p.61 / Appendix B. Derivation of the equation (4.16) --- p.63 / Appendix C. Different definitions of the norm --- p.64 / Bibliography --- p.66

We prove two results; first, we show that a boundary value problem for the semilinear wave equation with smooth, asymptotically linear nonlinearity and sinusoidal smooth forcing along a characteristic cannot have a continuous solution. Thereafter, we show that if the sinusoidal forcing is not isolated to a characteristic of the wave equation, then the problem has a continuous solution.

Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 126-131). Available also in a digital version from Dissertation Abstracts.

No description available.

Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 140-146). Available also in a digital version from Dissertation Abstracts.

No description available.

by Chan Kam Wai Clifford. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 105-108). / Text in English; abstracts in English and Chinese. / by Chan Kam Wai Clifford. / Abstract --- p.i / Acknowledgements --- p.iii / Contents --- p.iv / List of Figures --- p.vii / Chapter Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Motivations of the Project --- p.1 / Chapter 1.2 --- Historical Background --- p.1 / Chapter 1.3 --- Objective and Outline of Thesis --- p.3 / Chapter Chapter 2. --- Reviews on One-dimensional Dynamical Cavity --- p.4 / Chapter 2.1 --- Formalism --- p.4 / Chapter 2.2 --- Methods of Solution --- p.6 / Chapter 2.2.1 --- Phase Construction (R function) --- p.6 / Chapter 2.2.2 --- Instantaneous Mode Expansion --- p.12 / Chapter 2.2.3 --- Transformation Method --- p.15 / Chapter 2.3 --- Numerical Results --- p.15 / Chapter 2.3.1 --- Some Results using R function --- p.16 / Chapter 2.3.2 --- Some Results using Instantaneous Mode Decomposition --- p.24 / Chapter 2.3.3 --- Remarks on the Numerical Scheme used in Transformation Method --- p.28 / Chapter 2.3.4 --- "Comparisons of Results obtained by Phase Construction, In- stantaneous Mode Decomposition and Transformation" --- p.28 / Chapter 2.4 --- Conclusion --- p.30 / Chapter Chapter 3. --- Fixed-point Analysis for the One-dimensional Cavity --- p.31 / Chapter 3.1 --- Introduction --- p.31 / Chapter 3.2 --- What are the fixed-points? --- p.32 / Chapter 3.3 --- Characteristics of Fixed-points --- p.36 / Chapter 3.4 --- Fixed-points and Geometric Resonance --- p.39 / Chapter Chapter 4. --- Electromagnetic Field in an Undulating Spherical Cavity --- p.44 / Chapter 4.1 --- Classical Electromagnetic field theory --- p.44 / Chapter 4.2 --- Boundary Conditions --- p.46 / Chapter 4.3 --- The Motion of Cavity Surface --- p.47 / Chapter Chapter 5. --- Methods of Solution and Results to the Spherical Cavity --- p.48 / Chapter 5.1 --- Introduction --- p.48 / Chapter 5.2 --- Mode Decomposition and Transformation Method revisited --- p.49 / Chapter 5.2.1 --- Mode Decomposition --- p.49 / Chapter 5.2.2 --- Transformation Method --- p.50 / Chapter 5.2.3 --- Remarks on the use of Instantaneous Mode Expansion and Transformation Method --- p.51 / Chapter 5.3 --- The Ge(z) function --- p.52 / Chapter 5.3.1 --- The Ge(z) function as a solution of the scalar wave equation --- p.52 / Chapter 5.3.2 --- Numerical Results --- p.54 / Chapter 5.4 --- The Me(z) function --- p.60 / Chapter 5.4.1 --- Formalism --- p.60 / Chapter 5.4.2 --- Comparison of Me(z) with Ge(z) --- p.62 / Chapter 5.4.3 --- Numerical Results --- p.63 / Chapter 5.5 --- Conclusions and Discussions --- p.93 / Chapter 5.5.1 --- Geometric Resonances --- p.93 / Chapter 5.5.2 --- Harmonic Resonances --- p.94 / Chapter Chapter 6. --- Conclusion --- p.95 / Appendix A. Electromagnetic Field in Spherical Cavity --- p.97 / Chapter A.1 --- Field Strength --- p.97 / Chapter A.2 --- Field Energy --- p.98 / "Appendix B. Construction of Ψe(r,t) by G(z)" --- p.100 / Appendix C. The Arbitrary Part GH(z) of Ψe(r，t) --- p.103 / Bibliography --- p.105

The fractal dimension of measured ocean wave profiles is found to be in the range of 1.5-1.8. This non-integer dimension indicates the fractal nature of the waves. Standard formulations to analyze waves are based on a differential approach. Since fractals are non-differentiable, this formulation fails for waves with fractal characteristics. Integral solutions for long waves that are valid for a non-differentiable fractal surfaces are developed. Field observations show a positive correlation between the fractal dimension and the degree of nonlinearity of the waves, wave steepness, and breaking waves. Solutions are developed for a variety of linear cases. As waves propagate shoreward and become more nonlinear, the fractal dimension increases. The linear solutions are unable to reproduce the change in fractal dimension evident in the ocean data. However, the linear solutions do demonstrate a finite speed of propagation. The correlation of the fractal dimension with the nonlinearity of the waves suggests using a nonlinear wave equation. We first confirm the nonlinear behavior of the waves using the finite difference method with continuous function as the initial condition. Next, we solve the system using a Runge-Kutta method to integrate the characteristics of the nonlinear wave equation. For small times, the finite difference and Runge-Kutta solutions are similar. At longer times, however, the Runge-Kutta solution shows the leading edge of the wave extending beyond the base of the wave corresponding to over-steepening and breaking. A simple long wave solution on multi-step bottom is developed in order to calculate the reflection coefficient for a sloping beach. Multiple reflections and transmissions are allowed at each step, and the resulting reflection coefficient is calculated. The reflection coefficient is also calculated for model with thousands of small steps where the waves are reflected and transmitted once over each step. The effect of depth-limited breaking waves is also considered. / Graduation date: 2003

Thesis (Ph. D.)--University of Oregon, 2001. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 122-123). Also available for download via the World Wide Web; free to University of Oregon users.

Thesis (Ph. D.)--University of Texas at Austin, 2003. / Vita. Includes bibliographical references. Available also from UMI Company.