A Portable TV-Holography (ESPI) System for QNDE

Quantitative nondestructive evaluation of structures is achieved by this remote sensing technique which measures the deformation vector components of a surface in all 3 dimensions. Traditional techniques involve predominantly the application of strain gauges for the two in-plane deformation vector components. This technique unfortunately only reveals the in-plane deformation between two distinct points where the strain gauge is glued onto the surface. Interferometric techniques on the other hand are most common to measure the out-of-plane deformation component. Conventional film or thermoplastic holography is one of the most sensitive among those techniques measuring out-of-plane deformations in the micron and submicron range. One major disadvantage of this technique is the low time-resolution due to the fact that it involves the processing of photographic or thermoplastic film.</p

Bilateral sagittal split osteotomies (BSSO) versus mandibular distraction osteogenesis: which is better?

In recent years, Laser Speckle Pattern Interferometry(SPI) and its development have enabled surface deformation of structure components and materials to be accurately examined. SPI is a very useful method for measuring in-plane components of displacement. In measuring thermal expansion coefficient, the various problems are occurred, and the measuring limitation is existed. In this study, INCONEL 601 and Tantalum were used as specimen material. Specimens were heated to the high temperature(1000 °C) by electric current