The SGBEM-FEM alternating method is compared with the recently popularized XFEM, for analyzing mixed-mode fracture and fatigue growth of 3D nonplanar cracks in complex solid and structural geometries. A large set of 3D examples with different degrees of complexity is analyzed by the SGBEM-FEM alternating method, and the numerical results are compared with those obtained by XFEM available in the...

ACKNOWLEDGMENTS First of all, I would like to give my most sincere thanks to my advisor Professor Punam K. and Ryan Amelon for their help on my research. In the end, I want to thank all the faculty, staff and students of The Iowa Institute for Biomedical Imaging and Electrical and Computer Engineering for their improving lectures and kind help. iii ABSTRACT The finite element method (FEM) has b...

A new method of migration using the finite element method (FEM) and the finite difference method (FDM) is jointly used in the spatial domain. It has been applied to solve a time relay 2D wave equation. By using the semi-discretization technique of FEM in the spatial domain, the origin problem can be written as a coupled system of lower dimensions partial differential equations (PDEs) that conti...

Finite volume methods (FVM) and finite element methods (FEM) are popular tools to solve the parabolic partial differential equation describing the propagation of the electrical impulse in the heart muscle. This report demonstrates that these formulations are indeed equivalent provided that (1) linear elements are used for the FEM, and (2) the mass matrix is lumped. As a consequence, exact local...

The purpose of this paper is to present an adaptive FEM-BEM coupling method that is valid for both twoand three-dimensional elasto-plastic analyses. The method takes care of the evolution of the elastic and plastic regions. It eliminates the cumbersome of a trial and error process in the identification of the FEM and BEM sub-domains in the standard FEM-BEM coupling approaches. The method estima...

Polynomial extensions play a vital role in analysis of the p and h-p FEM as well as spectral element method. In this paper, we construct explicitly polynomial extensions on a triangle T and a square S, which lift a polynomial defined on a side Γ or on whole boundary of T or S. The continuity of these extension operators from H 1 2 00(Γ) to H (T ) or H(S) and from H 1 2 (∂T ) to H(T ) or from H ...

The replacement of steam catapults with electromagnetic ones is becoming an overwhelming trend in aircraft launch systems. The Electromagnetic Aircraft Launch System (EMALS) offers significant benefits to the aircraft, ship, personnel, and operational capabilities. EMALS has such advantages as high thrust, good controllability, reusable, etc., as a launching motor, a double-side plate Permanent...

A simultaneous two-parameter single sensor based on weakly tilted Fibre Bragg Grating (TFBG), embedded in a 1 mm glass fibre/epoxy composite plate, is demonstrated to measure independently the temperature and strain variations induced material by exposure heating lamps. The spectrum of TFBGs composed several peaks that can be used for different sensing purposes. Here, shifting Ghost are conside...

In Electro- (EEG) and Magnetoencephalography (MEG), one important requirement of source reconstruction is the forward model. The continuous Galerkin finite element method (CG-FEM) has become one of the dominant approaches for solving the forward problem over the last decades. Recently, a discontinuous Galerkin FEM (DG-FEM) EEG forward approach has been proposed as an alternative to CG-FEM (Engw...

The two best-known methods for calculating highfrequency winding loss in round-wire windings—the Dowell method and the Ferreira method—give significantly different results at high frequency. We apply 2-D finite-element method (FEM) simulations to evaluate the accuracy of each method for predicting proximity-effect losses. We find that both methods can have substantial errors, exceeding 60%. The...