Ocean acoustic interferometry (OAI) is a technique which relates the cross-correlations from a line of active sources to two receivers within a waveguide, and the time domain Green’s function between said receivers. Within this paper, three specific OAI source geometries are briefly introduced and explained. Experimental OAI data were collected during the SW06 (Shallow Water ’06) sea trials dur...

Ocean acoustic interferometry refers to an approach whereby signals recorded from a line of sources are used to infer the Green's function between two receivers. An approximation of the time domain Green's function is obtained by summing, over all source positions (stacking), the cross-correlations between the receivers. Within this paper a stationary phase argument is used to describe the rela...

For health monitoring of a building, we need to separate the response of the building to an earthquake from the imprint of soil-structure coupling and from wave propagation below the base of the building. Seismic interferometry based on deconvolution, where we deconvolve the wave fields recorded at different floors, is a technique to extract this building response and thus estimate velocity of ...

Measurement of the phenomena associated with hypervelocity boundary layer transition requires the development of high-speed detection techniques. Two reasons for the current search for a reliable non-intrusive optical technique include: 1) high-enthalpy facilities suffer from a harsh environment in the test section after the test time, 2) optical diagnostics tend to achieve higher sampling rate...

The phrase virtual source refers to two different techniques in this dissertation. In the first half of the dissertation, it refers to interferometry and in the second half it uses the concept of the synthetic aperture technique. In interferometry, a receiver is converted to a “virtual source”. In the synthetic aperture technique, a large “virtual source” is constructed by adding small sources....

The paper analyzes the effects of filling times and interval time on acoustic emission characteristics coda wave layered cemented tailings backfill under uniaxial compression and, to a certain extent, enriches study in this field. work aims monitor early warning with different layering factors during deformation damage by changing law ultrasonic signals. By conducting tests, emission, tests bac...