Application of the estimation of farfield radiation patterns from nearfield particle velocity to 3-D sound source.

Given the unsurpassed sound sensitivity of mosquitoes among arthropods and the sound source power required for long-range hearing, we investigated the distance over which female mosquitoes detect species-specific cues in the sound of station-keeping mating swarms. A common misunderstanding, that mosquitoes cannot hear at long range because their hearing organs are ‘particle-velocity’ receptors, has clouded the fact that particle velocity is an intrinsic component of sound whatever the distance to the sound source. We exposed free-flying Anopheles coluzzii females to pre-recorded sounds of male An. coluzzii and An. gambiae s.s. swarms over a range of natural sound levels. Sound levels tested were related to equivalent distances between the female and the swarm for a given number of males, enabling us to infer distances over which females might hear large male swarms. We show that females do not respond to swarm sound up to 48 dB sound pressure level (SPL) and that louder SPLs are not ecologically relevant for a swarm. Considering that swarms are the only mosquito sound source that would be loud enough to be heard at long range, we conclude that inter-mosquito acoustic communication is restricted to close-range pair interactions. We also showed that the sensitivity to sound in free-flying males is much enhanced compared to that of tethered ones.

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Herring Behaviour in the Dark: Responses to Stationary and Continuously Vibrating Obstacles

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400019494 ◽

1985 ◽

Vol 65 (4) ◽

pp. 1031-1049 ◽

Cited By ~ 29

Author(s):

J. H. S. Blaxter ◽

R. S. Batty

Keyword(s):

Particle Velocity ◽

Lateral Line ◽

Sound Source ◽

Sound Pressure ◽

Visual Stimuli ◽

Avoidance Behaviour ◽

Infra Red ◽

Stationary Obstacles

The behaviour of herring subjected to stationary and vibrating obstacles in their swimming path was recorded in daylight and darkness using an infra-red sensitive TV system. The herring avoided stationary obstacles using visual stimuli and usually collided with such obstacles in darkness. They showed strong avoidance to a continuously vibrating sound source in darkness but the speed of turning was relatively slow and there was no evidence for habituation. As they approached the source they usually responded when the sound pressure reached 10–20 Pa, about 70 dB above the threshold. Particle velocity within the lateral line canals was calculated and was 40–60 dB above threshold. Herring seem to be able to adapt their avoidance behaviour to suit the urgency of the situation.

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Sound Source Identification Based on Acoustic Source Quantification by Measuring the Particle Velocity Directly

Lecture Notes in Electrical Engineering - Proceedings of the FISITA 2012 World Automotive Congress ◽

10.1007/978-3-642-33832-8_22 ◽

2012 ◽

pp. 279-289

Author(s):

Byung Hyun Kim ◽

Tae Jin Shin ◽

Sang Kwon Lee

Keyword(s):

Particle Velocity ◽

Sound Source ◽

Source Identification ◽

Acoustic Source ◽

Sound Source Identification

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Role of pinnae and head movements in localizing pure tones 1The authors would like to thank Mr. Remi Humbert for implementing the experiment in Turbo Pascal and for his further assistance.

Swiss Journal of Psychology ◽

10.1024//1421-0185.58.3.170 ◽

1999 ◽

Vol 58 (3) ◽

pp. 170-179 ◽

Cited By ~ 4

Author(s):

Barbara S. Muller ◽

Pierre Bovet

Keyword(s):

Sound Source ◽

Head Movement ◽

Movement Analysis ◽

Head Movements ◽

Sound Sources ◽

Localization Accuracy ◽

Sound Effects ◽

Posterior Quadrant ◽

Localization Performance ◽

Pure Tones

Twelve blindfolded subjects localized two different pure tones, randomly played by eight sound sources in the horizontal plane. Either subjects could get information supplied by their pinnae (external ear) and their head movements or not. We found that pinnae, as well as head movements, had a marked influence on auditory localization performance with this type of sound. Effects of pinnae and head movements seemed to be additive; the absence of one or the other factor provoked the same loss of localization accuracy and even much the same error pattern. Head movement analysis showed that subjects turn their face towards the emitting sound source, except for sources exactly in the front or exactly in the rear, which are identified by turning the head to both sides. The head movement amplitude increased smoothly as the sound source moved from the anterior to the posterior quadrant.

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