This paper contains a linear analysis of pulse shapes produced by a spatial and temporal delta-function disturbance of cyclotron-resonance-maser modes for the case where the initial equilibrium state is free of radiation. A pinch-point analysis based on the theory of Briggs and Bers is employed. Numerical and analytical techniques are developed for the straightforward calculation of pinch-point...

PURPOSE There is a continuing need to improve the prediction of hip fractures to identify those at highest risk, enabling cost-effective use of preventative therapies. METHODS The aim of this work was to validate an innovative imaging biomarker for hip fracture by modelling the shape and texture of the proximal femur assessed from dual energy X-ray absorptiometry (DXA) scans. Scans used were ...

The demands by the semiconductors industry for high levels of integration, lower costs and a growing need for complete system solutions has led to the emergence of ”System In Package” (SIP) solutions in which ”the package is the system”. Since SIP-microsystems have multiple thin and stacked layers manufactured using different processes and materials, internal (intrinsic and/or thermal) mismatch...

Motivated by recent developments in laser-induced spallation testing of thin film structures, we develop a spectral scheme for the simulation of dynamic failure of thin films. In this first study, we focus on the anti-plane shear (mode 3) loading case. The scheme relies on an exact spectral representation of the elastodynamic solutions in the substrate and in the film, and their combination thr...

The cracked Brazilian disc (CBD) specimen is widely used in order to determine mode-I/II and mixed-mode fracture toughness of a rock medium. In this study, the stress intensity factor (SIF) on the crack-tip in this specimen is calculated for various geometrical crack conditions using the extended-finite element method (X-FEM). This method is based upon the finite element method (FEM). In this m...

In this paper mathematical formulation for buckling analysis of a column and vibrationanalysis of a beam is presented. The beam and the column is assumed to be non-uniform and cracked.Using calculus of variations, the problem is expressed as an optimization problem. A technique ofoptimization is used for analysis of buckling load. Considering the similarity between the governingequation for buc...

the drawing of frequency-path (f-p) models of optical beams is an approach for nonlinearity analysis in nano-metrology systems and sensors based on the laser interferometers. in this paper, the frequency-path models of four nano-metrology laser interferometry systems are designed, analyzed and simulated, including conventional and modified two- and three-longitudinal-mode laser interferometers....

Meshfree Galerkin approximations in both two and three dimensions have been used in simulations of dynamic shear band propagation in an asymmetrically impact-loaded prenotched plate. Failure mode switching and failure mode transitions, which have been reported experimentally, are replicated in numerical computations. For intermediate impact speed (25 m=s < V 6 30 m=s), the numerical results sho...