Background: The basic requirements for monitoring anesthetized patients during surgery are assessing cardiac and respiratory function. Esophageal stethoscopes have been developed for this purpose, but these devices may not provide clear heart and lung sound due to existence of various noises in operating rooms. In addition, the stethoscope is not applicable for continues monitoring, and it is u...

SUMMARY In the field of seismic interferometry, cross-correlations are used to extract Green’s function from ambient noise data. By applying a single station variation method, using autocorrelations, we in principle able retrieve zero-offset reflections stratified Earth. These valuable as they do not require an active source and, being zero-offset, better constrained space than passive earthqua...