Ultrasonic techniques have been used for many years for the inspection of rail. These measurements can detect the presence of a wide variety of defects but there are practical difficulties with the technology. While large transverse cracks of the type likely to cause catastrophic failure can be detected, the large, critical defects can be masked by large numbers of small, surface defects along ...

A welded structure must be inspected to guarantee that the weld quality meets the design requirements to assure safety and reliability. However, X-ray image analyses and defect recognition with the computer vision techniques are very complex. Most difficulties lie in finding the small, irregular defects in poor contrast images which requires pre processing to image, extract, and classify featur...

An application of machine vision, incorporating neural networks, which aims to fully automate real-time radiographic inspection in welding processes is described. The current methodology adopted comprises two distinct stages the segmentation of the weld from the background content of the radiographic image, and the segmentation of suspect defect areas inside the weld region itself. In the first...

Management of long bone defects occurring in accidents or war injuries is a difficult problem, From 1978 to 1986, 11 patients were treated for long bone defects of the humerus ( 10 cases) and radius (one case), using free vascularized fibular transfer by microsurgical technique .The patients were followed for 4 months and in all of them, selective angiography and scanning revealed exellent...

Mathematical models and associated numerical techniques have been developed to investigate the complicated transport phenomena in spot hybrid laser-MIG keyhole welding. A continuum formulation is used to handle solid phase, liquid phase, and the mushy zone during the melting and solidification processes. The volume of fluid (VOF) method is employed to handle free surfaces, and the enthalpy meth...

Evaluation of the low cycle fatigue life by the small specimen test technique (SSTT) and some other properties (metallographical structure and Vickers hardness) for the TIG (tungsten inert gas) weld of F82H IEA-heat were carried out. The TIG-weld was distinguished into seven regions with different metallographical structure and hardness, which were the base metal (BM) region (region with almost...