We investigate the application of artificial neural networks (ANNs) to the classification of spectra from impact-echo signals. In this paper we provide analyses from simulated signals and the second part paper details results of lab experiments. The data set for this research consists of sonic and ultrasonic impact-echo signal spectra obtained from 100 3D-finite element models. These spectra, a...

In 4D printing research, different types of complex structure folding and unfolding have been investigated. However, research on cross-folding of origami structures (defined as a folding structure with at least two overlapping folds) has not been reported. This research focuses on the investigation of cross-folding structures using multi-material components along different axes and different ho...

ÐWe analyse the development of shear bands in axisymmetric, thermomechanical deformations of a circular tungsten heavy alloy (WHA) rod impacting at normal incidence a smooth rigid target. The rod's material is modeled either as a mixture of Fe±Ni±W particles interspread randomly among the W-particles or as a homogeneous alloy. For comparison purposes we also analyse deformations of a pure W and...

let be a locally compact non?abelian group and be a compact subgroup of also let be a ?invariant measure on the homogeneous space . in this article, we extend the linear operator as a bounded surjective linear operator for all ?spaces with . as an application of this extension, we show that each frame for determines a frame for and each frame for arises from a frame in via the linear operator .

In the existing finite element head models (FEHMs) that are constructed from medical images, head tissues are usually segmented into a number of components according to the interior anatomical structure of the head. Each component is represented by a homogenous material model. There are a number of disadvantages in the segmentation-based finite element head models. Therefore, we developed a non...

In this paper we examine modeling and metamodeling for metadata. We illustrate the need of metamodeling through three examples where metadata sets are used to efficiently process internal functions. We show that several levels of metamodeling are required in order to efficiently support essential functions provided by these systems. We argue that extensible metadata managers should support (i) ...

Membranous lipodystrophy is characterized by the presence of microcysts lined by amorphous, eosinophilic material with an arabesque appearance. We experienced a case of a 72-year-old man who had dark brownish, pruritic papules on the arms, legs, and back. Histopathologic examination of a biopsied lesion showed homogeneous, eosinophilic material in the papillary dermis, as well as membranous lip...

When a (frequency–domain) boundary value problem involving a homogeneous linear material is solved to assess the validity of the Post constraint, a conflict arises between the fundamental differential equations of electromagnetism in the chosen material and a näive application of the usual boundary conditions. It is shown here that the conflict vanishes when the boundary conditions are properly...

A rate-dependent model is used to represent the bridging forces acting across a 'ber-bridged slit crack in a homogeneous anisotropic elastic material, with the potential to characterize the inelastic behavior of bridged cracks in composites. The basic equilibrium equations are presented and solved, using a series of Chebychev polynomials and a suitable approximation numerical scheme. An example...