A damage detection algorithm based on the proper orthogonal decomposition technique is presented for health monitoring of structures. The proper orthogonal modes are employed as dynamical invariants to filter out the influence of operational/environmental variations on the dynamic response of the structure. Finite element model of a carbon/epoxy composite plate is used to generate vibration dat...

The vascularity of ii hearts with endomyocardialfibrosis, which were part of a larger series of I47 heartsfrom patients dying at the Mulago Hospital, Kampala, Uganda, have been studied by injection, microradiographic, and histological techniques. A complete range of pathological types of endomyocardial fibrotic hearts were studied. Every heart showed some pericarditis and small scars scattered ...

The objective of this study is to create building damage hazard zonation area using fuzzy kohonen clustering network (FKCN) for physical parameter data clustering and inverse distance weighting (IDW) for data interpolation in Banda Aceh city, Indonesia. IDW algorithm is used alongside FKCN because of its simplicity. The physical parameter in this study consists of lithology, topographic zone an...

This paper develops a two-stage stochastic program and solution procedure to optimize the selection of seismic retrofit strategies to increase the resilience of electric power systems to earthquake hazards. The model explicitly considers the range of earthquake events that are possible and, for each, an approximation to the distribution of damage that is experienced. This is important because e...

In this paper, quantitative evaluation of ultrasonic Cscan images through estimation of their Fractal Dimension (FD) is discussed. Necessary algorithm for evaluation of FD of any 2-D digitized image is implemented by developing a computer code. For the evaluation purpose several C-scan images of the Kevlar composite impacted by high speed bullet and glass fibre composite having flaw in the form...

We simulate the propagation of a planar crack in a quasi-two dimensional fuse model, confining the crack between two horizontal plates. We investigate the effect on the roughness of microcrack nucleation ahead of the main crack and study the structure of the damage zone. The two dimensional geometry introduces a characteristic length in the problem, limiting the crack roughness. The damage ahea...

[1] We investigate the development of fracture distributions as a function of displacement to determine whether damage around small and large faults is governed by the same process. Based on our own field work combined with data from the literature, we find that (1) isolated single faults with small displacements have macrofracture densities that decay as r, where r is distance from the fault p...

Positron Annihilation Doppler Broadening Spectroscopy (PADBS) is a characterization technique that is sensitive to damage of radiation in polymers. A damage zone or defect will be created due to the irradiation of Polyallyl diglycol carbonate (CR-39) with α-particles. It is convenient to study this defect caused by α-particle energies using both PADBS and track diameter measurements. An abrupt ...

We have analyzed by transmission electron microscopy silicon and GaAs crystals polished with sandpapers of different grain size. The surface damage induced a crystal permanent convex curvature with a radius of the order of a few meters. The curvature is due to a compressive strain generated in the damaged zone of the sample. Contrary to what was reported in the literature, the only defects dete...

Abstract Metallic materials exhibit pronounced strain localization during damage and failure, posing a challenge in mechanics when predicting the change size of zone. In this study, uniaxial tensile tests were carried out to observe changes zone loading aluminum low-carbon steel. The initial final states two metallic deformation compared. shrank gradually with increase load, which agrees existi...