XLI. Acoustical observations.—IV

Xli. Gas-electrode for General Use

Multi-spectral acoustical imaging

Visualization of object through acoustic waves is generally called as acoustical imaging. This concept contain noise source localization, ultrasonic non-destructive testing, medical ultrasound, underwater sonars, etc. In these conventional imaging techniques, frequency information has not yet utilized effectively, though shape, material and even structure behind the surface reflect on the frequ...

XLI. A map of lensing-induced B-modes

The secondary cosmic microwave background (CMB) B-modes stem from the post-decoupling distortion of the polarization E-modes due to the gravitational lensing effect of large-scale structures. These lensing-induced B-modes constitute both a valuable probe of the dark matter distribution and an important contaminant for the extraction of the primary CMB B-modes from inflation. Planck provides acc...

Fast wideband acoustical holography.

Patch near-field acoustical holography methods like statistically optimized near-field acoustical holography and equivalent source method are limited to relatively low frequencies, where the average array-element spacing is less than half of the acoustic wavelength, while beamforming provides useful resolution only at medium-to-high frequencies. With adequate array design, both methods can be u...

Acoustical Standards News.

American National Standards (ANSI Standards) developed by Accredited Standards Committees S1, S2, S3, S3/SC 1, and S12 in the areas of acoustics, mechanical vibration and shock, bioacoustics, animal bioacoustics, and noise, respectively, are published by the Acoustical Society of America (ASA). In addition to these standards, ASA publishes a catalog of Acoustical American National Standards. To...