We carry out a nondestructive study of injection-mold weld lines in an acrylonitrile butadiene styrene (ABS) thermoplastic electrical receptacle plate. Terahertz techniques show morphological features at the and reveal terahertz birefringence properties localized around welds, indicating frozen-in molecular orientation stress proximate to welds. Surface acoustic microscopy corroborates welds sh...

Silicon (Si) films were obtained through aluminothermic reduction of the quartz (SiO 2 ) substrates, where surface in contact with deposited aluminum (Al) layer has been converted to film Si during high-temperature annealing following reaction. X-ray diffraction (XRD) patterns and Raman spectra show dominating peaks corresponding elemental films. Energy dispersive spectroscopy (EDS), as well XR...

Horizontal black surfaces are usually very attractive to polarotactic aquatic insects, since they generally reXect highly and horizontally polarized light, and thus imitate water surfaces. We monitored highly polarizing black burnt-up stubble-Welds, but surprisingly never found aquatic insects or their carcasses in the ash, although Xying polarotactic insects were abundant in the area, which we...

This work applies 64,765 simulated seismic ground motions to four models each of 6or 20-story, steel special moment-resisting frame buildings. We consider two vector intensity measures and categorize the building response as “collapsed,” “unrepairable,” or “repairable.” We then propose regression models to predict the building responses from the intensity measures. The best models for “collapse...

final step of rail manufacturing is cold rolling straightening process and it hassignificant effects on mechanical properties, straightness, flatness and development of residualstresses. measurement of residual stresses after straightening process is obligated by railmanufacturing standards. in the present investigation, an attempt has been made to evaluateresidual stresses after straightening ...

A high frequency ultrasound imaging technique was applied for quality control of several kinds of projection welds originating from automotive production. The projection welds were formed between V-shaped surfaces of solid components and zinc-coated steel sheets. Acoustic images were obtained both in high resolution and in express regime. Detailed three-dimensional data cubes were acquired usin...

Safety levels at highway – rail level crossing locations continue to be a major concern at most of developing countries. Basically more than half of these accidents occur at public crossings, where active warning devices are in place and functioning properly. In most cases, accidents occurred when road users ignored the gates and passed through them or if they stopped on the tracks before the g...