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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.
131

Mie's scattering: a morphology-dependent resonance approach. / 米氏散射--以形態關聯共振分析之 / Mie's scattering: a morphology-dependent resonance approach. / Mi shi san she--yi xing tai guan lian gong zhen fen xi zhi

January 2000 (has links)
Ng Sheung Wah = 米氏散射--以形態關聯共振分析之 / 伍尚華. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves [112]-114). / Text in English; abstracts in English and Chinese. / Ng Sheung Wah = Mi shi san she--yi xing tai guan lian gong zhen fen xi zhi / Wu Shanghua. / Abstract --- p.i / Acknowledgements --- p.iii / Contents --- p.iv / List of Figures --- p.vii / List of Tables --- p.xii / Chapter Chapter 1. --- Introduction --- p.1 / Chapter Chapter 2. --- MDR Expansion of Scattering Matrix --- p.7 / Chapter 2.1 --- Introduction --- p.7 / Chapter 2.2 --- Definition of Scattering Matrix --- p.8 / Chapter 2.3 --- Expansion of St with MDR's --- p.9 / Chapter 2.4 --- The Scattering Matrix in Mie's Theory for Uniform Dielectric Spheres --- p.12 / Chapter 2.5 --- Convergence of the Series --- p.15 / Chapter 2.6 --- Contributions of Different MDR's in Cross Section --- p.19 / Chapter Chapter 3. --- Numerical Method for MDR's --- p.27 / Chapter 3.1 --- Multipole Expansion --- p.27 / Chapter 3.2 --- Green's Theorem --- p.29 / Chapter 3.3 --- Translational Matrix --- p.31 / Chapter 3.4 --- Rotational Matrix --- p.36 / Chapter 3.5 --- Transfer Matrix to the Outside --- p.39 / Chapter 3.6 --- Diagonalization --- p.40 / Chapter Chapter 4. --- Degenerate Perturbation for MDR --- p.44 / Chapter 4.1 --- Introduction --- p.44 / Chapter 4.2 --- Perturbation Theory for Degenerate Systems --- p.44 / Chapter Chapter 5. --- Microdroplets with multiple inclusions: Experiments --- p.52 / Chapter 5.1 --- Introduction --- p.52 / Chapter 5.2 --- Method --- p.52 / Chapter Chapter 6. --- Formalism for Scattering from Inhomogeneous Spheres --- p.61 / Chapter 6.1 --- The Green's Function Formalism --- p.61 / Chapter 6.2 --- MDR Expansion of Dyadic Green's Function --- p.62 / Chapter 6.3 --- Cross Section Calculation --- p.64 / Chapter Chapter 7. --- Simulation of the Multiple Scattering Experiment --- p.66 / Chapter 7.1 --- Introduction --- p.66 / Chapter 7.2 --- Method --- p.67 / Chapter Chapter 8. --- Numerical Results of Multiple Scattering --- p.69 / Chapter 8.1 --- Introduction --- p.69 / Chapter 8.2 --- Comparisons of the Experimental and Simulation Result --- p.69 / Chapter 8.2.1 --- General Trend --- p.69 / Chapter 8.2.2 --- Position of the Resonance --- p.70 / Chapter 8.2.3 --- Width of the Resonance --- p.71 / Chapter Chapter 9. --- Scaling Behaviours of the Perturbation in MDR's --- p.83 / Chapter 9.1 --- Introduction --- p.83 / Chapter 9.2 --- Scaling Behaviours of MDR's shifts --- p.84 / Chapter 9.3 --- Analytical Approach to the Scaling Behaviours --- p.84 / Chapter 9.3.1 --- Average Shifts --- p.85 / Chapter 9.3.2 --- """slope"" of the Shifts" --- p.87 / Chapter 9.3.3 --- Spreading of the shifts --- p.87 / Chapter Chapter 10. --- Conclusion --- p.96 / Appendix A. Transverse Dyadic Green's Function Expansion --- p.98 / Appendix B. Calculation of the Self-Energy Matrix to First Order --- p.101 / Appendix C. Computer Code for Diagonalization of Δmm --- p.103 / Bibliography --- p.112
132

Complex source point beam expansions for some electromagnetic radiation and scattering problems

Tap, Koray, January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 204-208).
133

Time domain modeling of electromagnetic radiation with application to ultrafast electronic and wireless communication

Remley, Catherine A. 16 March 1999 (has links)
Graduation date: 1999
134

Propagation of an electromagnetic wave along a helix surrounded by a resistance sheath

January 1952 (has links)
Andreas Tonning. / "May 13, 1952." / Bibliography: p. 11. / Army Signal Corps Contract No. DA36-039 sc-100 Project No. 8-102B-0. Dept. of the Army Project No. 3-99-10-022.
135

Matric algebra of electromagnetic waves

January 1948 (has links)
N.G. Parke, III. / "June 30, 1948." / Includes bibliographical references. / Army Signal Corps Contract No. W-36-039 sc-32037.
136

Wave-packet dynamics in slowly perturbed crystals : gradient corrections and Berry-phase effects /

Sundaram, Ganesh, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 62-68). Available also in a digital version from Dissertation Abstracts.
137

The design of broadband radar absorbing surfaces

Go, Han Suk. January 1990 (has links) (PDF)
Thesis (M.S. in System Engineering in Electronic Warfare)--Naval Postgraduate School, September 1990. / Thesis Advisor(s): Atwater, H.A. Second Reader: Janaswamy, R. "September 1990." Description based on title screen as viewed on December 29, 2009. DTIC Identifier(s): Radar absorbing materials, radar cross sections, radiation absorbers, lossy dielectrics. Author(s) subject terms: Wave absorber, dielectric material. Includes bibliographical references (p. 55-56). Also available in print.
138

A model for multi-wave beam-plasma interaction

Evstatiev, Evstati Georgiev 28 August 2008 (has links)
Not available / text
139

Simulation and inversion of borehole electromagnetic measurements for the estimation of petrophysical properties in the presence of mud-filtrate invasion

Salazar Luna, Jesús Mauricio, 1974- 29 August 2008 (has links)
Acoustic, electromagnetic (EM), and nuclear open-hole measurements are affected by fluids saturating near-wellbore porous and permeable rock formations, including hydrocarbons, water, and mud filtrate. Fluid invasion effects can be quantified and advantageously used to estimate petrophysical properties of the invaded rock formations. This dissertation incorporates the physics of water-base mud- (WBM) and oil-base mud- (OBM) filtrate invasion to the simulation and inversion of borehole EM measurements. We assume vertical boreholes penetrating clastic hydrocarbon- or water-bearing formations subject to either WBM- or OBM-filtrate invasion. The simulation of EM measurements in the presence of mud-filtrate invasion considers three different approaches: (1) piston-like invasion profiles, where we solely consider invaded- (flushed) and virgin- (uncontaminated) zones, (2) two-phase immiscible displacement and salt mixing between the invading WBM filtrate and connate water, and (3) invasion of single or multi-component OBM-filtrate into a formation saturated with multiple hydrocarbon components wherein the individual components are first-contact miscible. The last two approaches honor the physics of mudcake growth as well as the petrophysical properties that govern the process of multi-phase, multi-component fluid-flow displacement and include the presence of irreducible, capillary-bound and movable water. Electromagnetic measurements are simulated from spatial distributions of electrical resistivity calculated from the simulations of mud-filtrate invasion using clean- or shaly-sand water-saturationresistivity models. Inversion of petrophysical properties is posed as the nonlinear minimization of quadratic objective functions that quantify the misfit between EM measurements and their simulations. In the case of WBM piston-like invasion profiles in water-bearing formations, combined inversion of array-induction resistivity and spontaneous potential (SP) measurements yields connate water electrical resistivity and Archie’s cementation exponent. Permeability is calculated from the inversion of array-induction resistivity measurements assuming immiscible fluid-flow displacement of WBM into hydrocarbonbearing formations. Accurate reconstructions of layer-by-layer permeability are primarily constrained by the availability of a-priori information about time of invasion, rate of mud-filtrate invasion, overbalance pressure, capillary pressure, and relative permeability. This dissertation also quantifies the influence of petrophysical and fluid properties on borehole resistivity measurements acquired in the presence of compositional mixing of OBM filtrate invading partially hydrocarbon-saturated rock formations. Numerical simulations of OBM-filtrate invasion are performed with an adaptive-implicit compositional formulation that allows one to quantify the effects of additional components of mud-filtrate and native fluids on EM measurements. Perturbations of petrophysical and fluid properties enable the quantification of rock wettability changes due to OBM-filtrate invasion and their effect on the simulated induction resistivity measurements. Finally, simulations of induction resistivity measurements in the presence of OBM are compared to the corresponding measurements in the presence of WBMfiltrate invasion. The latter analysis allows us to estimate a realistic flow rate of OBMfiltrate invasion that is responsible for the variation of induction resistivity measurements as a function of their radial length of response. The combined simulation of the physics of mud-filtrate invasion and EM measurements provides reliable estimates of true formation resistivity and hence of water saturation, thereby improving the assessment of in-place hydrocarbons reserves. / text
140

Polarization transfer of electromagnetic waves in inhomogeneous magnetized plasma

鄭恢俊, Cheng, Fai-tsun. January 1976 (has links)
published_or_final_version / Physics / Doctoral / Doctor of Philosophy

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