Digitized by Kansas Correctional Industries

Surface integral equation (SIE) method with the kernel of layered medium Green's function (LMGF) is investigated in details from several fundamental aspects. A novel implementation of discrete complex image method (DCIM) is developed to accelerate the evaluation of Sommerfeld integrals and especially improve the far field accuracy of the conventional one. To achieve a broadband simulation of thin layered structure such as microstrip antennas, the mixed-form thin-stratified medium fast-multipole algorithm (MF-TSM-FMA) is developed by applying contour deformation and combining the multipole expansion and plane wave expansion into a single multilevel tree. The low frequency breakdown of the integral operator is further studied and remedied by using the loop-tree decomposition and the augmented electric field integral equation (A-EFIE), both in the context of layered medium integration kernel. All these methods are based on the EFIE for the perfect electric conductor (PEC) and hence can be applied in antenna and circuit applications. To model general dielectric or magnetic objects, the layered medium Green's function based on pilot vector potential approach is generalized for both electric and magnetic current sources. The matrix representation is further derived and the corresponding general SIE is setup. Finally, this SIE is accelerated with the DCIM and applied in quantum optics, such as the calculation of spontaneous emission enhancement of a quantum emitter embedded in a layered structure and in the presence of nano scatterers. / published_or_final_version / Electrical and Electronic Engineering / Doctoral / Doctor of Philosophy

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Call number: LD2668 .T4 1966 K92 / Master of Science

In this parametric inverse problem, we consider a lossless dielectric slab excited by a transient plane wave. The scattered electric field from the slab is presented in the ray-optic and the complex-resonance forms. Our interest is to extract the complex-resonances of the system in order to identify the parameters that describe the scatterer. We review the signal processing procedure and the identification procedure employed to identity the poles of the system. We investigate the effect of noise on identification and determine the maximum amount of noise one can impose on the system. In addition, we study the effect of data truncation on our identification procedure. We also discuss the parameters that dictate the minimum record required for successful identification. Finally, we demonstrate some similarities in effect of noise and truncation on our identification process.

No description available.

Thesis (Ph. D.)--University of Washington, 1990. / Vita. Includes bibliographical references (leaves [100]-106).

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In the past forty years, much work has been done in the area of multiple scattering effects on the propagation of electromagnetic waves in a random particulate medium. This work is important to wave propagation in the atmosphere, the planetary sphere, and the ocean. Current research is aimed at high frequencies (gigahertz to terahertz). At these frequencies, multiple scattering effects become very important since the wavelength reduces to the size of a particle. The purpose of this thesis is to augment the Twersky theory of multiple scattering in a random particulate medium. Most applications of Twersky’s work use a far-field approximation and a point-particle assumption. At high frequencies, particle sizes may be large relative to a wavelength; therefore, the point-particle assumption is inaccurate. Under a low-density approximation, this thesis introduces a scattering operator, which defines closed equations for the fields due to multiple scattering. The low-density approximation holds for many media (e.g. clouds and rain). The scattering operator may be solved for various particle shapes, eliminating the need for the point-particle assumption. / Master of Science

This research presents two switching techniques using SOT and SLACK, as complementary sequencing rules, to show that they are practical procedures to control a job shop. These two approaches are: - Static switching of the complementary rules. - Dynamic switching of the complementary rules. This study also presents questions which arise in creating different switching rules or procedures for an interactive scheduling system. It is also developed a normalized objective function to measure the balance of the best properties produced by SOT (low flow time) and SLACK (low tardiness). It should be noted that even though such a system could be viewed as complex and expensive,it is not. Computational requirement will be slightly increased, but no more data is required than is expected for a typical scheduling procedure. Finally, a procedure to calculate the upper and lower limits is presented for dynamic switching procedures. / Master of Science