Acoustic microcavitation: Its active and passive acoustic detection

Passive Acoustic Monitoring Bioacoustical Monitoring in Terrestrial Environments Counting Critters in the Sea Using Active Acoustics Passive Acoustic Monitoring for Estimating Animal Density and More Passive Acoustic Monitoring for Estimating Animal Density 35 PASSIVE ACOUSTIC MONITORING FOR ESTIMATING ANIMAL DENSITY

Active-passive gradient shielding for MRI acoustic noise reduction.

An important source of MRI acoustic noise-magnet cryostat warm-bore vibrations caused by eddy-current-induced forces-can be mitigated by a passive metal shield mounted on the outside of a vibration-isolated, vacuum-enclosed shielded gradient set. Finite-element (FE) calculations for a z-gradient indicate that a 2-mm-thick Cu layer wrapped on the gradient assembly can decrease mechanical power d...

Using paired visual and passive acoustic surveys to estimate passive acoustic detection parameters for harbor porpoise abundance estimates.

Passive acoustic monitoring is a promising approach for monitoring long-term trends in harbor porpoise (Phocoena phocoena) abundance. Before passive acoustic monitoring can be implemented to estimate harbor porpoise abundance, information about the detectability of harbor porpoise is needed to convert recorded numbers of echolocation clicks to harbor porpoise densities. In the present study, pa...

Passive acoustic detection of deep-diving beaked whales.

Beaked whales can remain submerged for an hour or more and are difficult to sight when they come to the surface to breathe. Passive acoustic detection (PAD) not only complements traditional visual-based methods for detecting these species but also can be more effective because beaked whales produce clicks regularly to echolocate on prey during deep foraging dives. The effectiveness of PAD for b...

Effects of subsampling of passive acoustic recordings on acoustic metrics.

Passive acoustic monitoring is an important tool in marine mammal studies. However, logistics and finances frequently constrain the number and servicing schedules of acoustic recorders, requiring a trade-off between deployment periods and sampling continuity, i.e., the implementation of a subsampling scheme. Optimizing such schemes to each project's specific research questions is desirable. Thi...