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Using GL no scattering full wave modeling and inversion, we create a GLHUA pre cloak electromagnetic (EM) material in the virtual sphere that makes the sphere is invisible. The invisible sphere is called GLHUA sphere. In GLHUA sphere, the Pre cloak relative parameter is not less than 1; the parameters and their derivative are continuous across the boundary r=R2 and the parameters are going to infinity at origin r=0. The phase velocity of EM wave in the sphere is less than light speed and going to zero at origin. The EM wave field excited in the outside of the sphere can not be disturbed by GLHUA sphere. By GL full wave method, we rigorously proved the incident EM wave field excited in outside of GLHUA sphere and propagation through the sphere without any scattering by the sphere, the total EM field in outside of the sphere equal to the incident wave field. Moreover, we prove that in GLHUA sphere with the pre cloak material, when r is going to origin, EM wave field propagation in GLHUA sphere is going to zero. All copyright and patent of the GLHUA EM cloaks,GLHUA sphere and GL modeling and inversion methods are reserved by authors in GL Geophysical Laboratory.

Thesis advisor,Michael R. Gorman

Knowledge of the elastic properties of composite materials can be an invaluable tool for both the quality assurance of manufacturing techniques and design verification. Recent advancements in ultrasonic velocity measurements have demonstrated the ability to recover elastic properties in anisotropic laminates. A simplified experimental setup was investigated to recover the elastic properties based on the flexural wave propagation in anisotropic laminates. The initial objective of this thesis was to verify flexural wave propagation in composite laminates through the comparison of experimental and theoretical phase velocities. In the second part of this thesis, the experimental phase velocities were used to calculate the elastic properties of the material by inverting the governing equations. The initial method used to recover elastic constants was successful in the recovery of a partial set of the bending and extensional stiffnesses. The inability to recover all bending stiffnesses dictated the investigation of a second method. This method used an iterative method based on a nonlinear Newton's method to recover the bending stiffnesses. This method did not converge due to ill conditioning of the solution matrix. Although this method did not converge, it is believed that other more robust methods suggested herein would converge to the proper solution.

To create a suite of computer codes (programs) that accurately model wave propagation and scattering in shallow water, to quantify the effects of poroelastic, stratified sediment and elastic mode conversion on wave propagation in shallow water at frequencies ranging from 10 Hz to several hundred kHz. To relate these effects to sonar system behavior and efficient design of sonar capable of finding buried/semi-buried/proud mines in shallow water environments, in the presence of poroelastic sediment and bubble layers. To understand the fundamental linear and nonlinear physics of wave propagation in poroelastic sediment with bubbles. To continue development and testing of K-space Integral Equation codes (K-SIE), finite difference time domain codes (FDTD), and Hybrid Parabolic marching/Finite difference (HP-MFD) and Hybrid Integral Equation/Finite Difference (HIEFD) methods for fast and accurate scattering and inverse scattering of objects buried in sediment with poroelastic (Biot) properties and containing bubble populations. To develop a Java-based, interactive, web site http://borup.aim.utah.edu [41] to make pseudo-analytic, FDTD, Integral Equation, and HIEFD and HP-MFD calculation methods in 3D and 2D, available to other researchers over the web.

To create a suite of computer codes (programs) that accurately model wave propagation and scattering in shallow water, to quantify the effects of poroelastic, stratified sediment and elastic mode conversion on wave propagation in shallow water at frequencies ranging from 10 Hz to several hundred kHz. To relate these effects to sonar system behavior and efficient design of sonar capable of finding buried/semi-buried/proud mines in shallow water environments, in the presence of poroelastic sediment and bubble layers. To understand the fundamental linear and nonlinear physics of wave propagation in poroelastic sediment with bubbles. To continue development and testing of K-space Integral Equation codes (K-SIE), finite difference time domain codes (FDTD), and Hybrid Parabolic marching/Finite difference (HP-MFD) and Hybrid Integral Equation/Finite Difference (HIEFD) methods for fast and accurate scattering and inverse scattering of objects buried in sediment with poroelastic (Biot) properties and containing bubble populations. To develop a Java-based, interactive, web site http://borup.aim.utah.edu [41] to make pseudo-analytic, FDTD, Integral Equation, and HIEFD and HP-MFD calculation methods in 3D and 2D, available to other researchers over the web.

Knowledge of the elastic properties of composite materials can be an invaluable tool for both the quality assurance of manufacturing techniques and design verification. Recent advances in ultrasonic velocity measurements have demonstrated the ability to recover elastic properties in anisotropic laminates. A simplified experimental setup was investigated to recover the elastic properties based upon the flexural wave propagation in anisotropic laminates. The initial objective of this thesis was to verify flexural wave propagation in composite laminates through the comparison of experimental and theoretical phase velocities. In the second part of this thesis, the experimental phase velocities were used to calculate the elastic properties of the material by inverting the governing equations. The initial method used to recover elastic constants was successful in the recovery of a partial set of the bending and extensional stiffnesses. The inability to recover all bending stiffnesses dictated the investigation of a second method. This method used an iterative method based upon a nonlinear Newton's method to recover the bending stiffnesses. This method did not converge due to the ill conditioning of the solution matrix. Although this method did not converge, it is believed that more robust methods suggest herein would converge to the proper solution.

The long-term goal is to create codes accurately model wave propagation and scattering in shallow water, and to quantify effects of poroelastic, stratified sediment and elastic mode conversion. Also to relate these effects to sonar system behaviour and optimization-based inversion of sediment acoustic and elastic properties.