Ultrafast laser techniques have opened up a tremendous research opportunity in studying the interaction of short pulses of light with matter. With discovering of the picosecond photoconducting hertzian dipoles and high-brightness THz beams characterized with an ultrafast detector, we have seen more and more applications of ultrafast light in noninvasive imaging. Standard methods, when applied t...

Edge illumination (EI) is an x-ray phase-contrast imaging technique, exploiting sensitivity to x-ray refraction to visualize features, which are often not detected by conventional absorption-based radiography. The method does not require a high degree of spatial coherence and is achromatic and, therefore, can be implemented with both synchrotron radiation and commercial x-ray tubes. Using diffe...

Lefkada and Corfu old towns are located in the western part of Greece, Ionian Sea. Their proximity to Hellenic subduction zone (HSZ) is reason for their intense seismicity. The main goal this study was estimation geotechnical characteristics subsurface, with contribution applied geophysical techniques. Therefore, seismic refraction tomography (SRT) multichannel analysis surface waves (MASW) wer...

A RECENT seismic refraction profile1 in 2,800 fm. (5.1 km.) at latitude 34° 00' N, longitude 66° 30' W, in the Atlantic Ocean proved that basement rocks having a velocity of 7.58 km/sec. for compressional waves were covered by 1.37 km. of sediment. We tentatively identified this velocity with either the P n velocities used in earthquake seismology for the ultra basic layer immediately beneath t...

PURPOSE To investigate the effects of age, eye refraction, and disc area on topographic parameters of the optic nerve head in normal volunteers, using the Heidelberg Retina Tomograph. METHODS Seventy-seven eyes of 77 normal volunteers were examined by scanning laser tomography. The topographic parameters analyzed were disc area, cup area, cup/disc area ratio, rim area, cup volume, rim volume,...

introduction: occurrence of landslides depends on several factors such as the composition and structure of earth materials, rainfall level, temperature, groundwater regime and cover crops. landslides are a main natural hazard in iran, because of its special geological conditions and its mountainous active tectonic regime. linear civil structures, such as roads, highways and railways, face serio...

Spectral Domain Optical Coherence Tomography System Development for In Vivo Ophthalmic Imaging by Mingtao Zhao Department of Biomedical Engineering Duke University Date:____September 17, 2009____________ Approved: ___________________________ Joseph A. Izatt, Supervisor ___________________________ David J. Brady ___________________________ Vo-Dinh Tuan ___________________________ Adam P. Wax ___...

This paper considers the joint use of two popular geophysical methods (fracture-induced electromagnetic radiation and seismic refraction tomography) to assess stress-state in underground mine-workings. Such a combination indirect allows identification zones increased stress rock along axis mine-workings, intense weakening or disintegration massif above roof The measurements longitudinal compres...

We present a simple closed-form expression for the reflectivity horn a multilayer which includes the effects of absorption, refraction, surface and substrate reflections but neglects dynamical effects. This expression reproduces the exact dynamical calculation except for the regions near the critical angle and for intense Bragg reflections. The expression is generalized to include cumulative in...