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The hypersonic effect is a phenomenon reported in a controversial scientific study by Tsutomu Oohashi et al., [3] which claims that, although humans cannot ...
Ultrasound is sound waves with frequencies higher than 20,000 Hz. Ultrasound is not different from audible sound in its physical properties, but cannot be heard by humans. Ultrasound devices operate with frequencies from 20 kHz up to several gigahertz. Medical ultrasound is commonly used for diagnostics and treatment.
Ultrasound is used to evaluate fat thickness, rib eye area, and intramuscular fat in living animals. [48] It is also used to evaluate the health and characteristics of unborn calves. Ultrasound technology provides a means for cattle producers to obtain information that can be used to improve the breeding and husbandry of cattle.
They are emitted by animals such as bats and rodents, and have been extensively studied in rats and mice. As opposed to sonic vocalizations, ultrasonic vocalizations cannot be detected by the human ear. USVs serve as social signals, [2] and are categorized according to their frequency.
Sound from ultrasound is the name given here to the generation of audible sound from modulated ultrasound without using an active receiver. This happens when the modulated ultrasound passes through a nonlinear medium which acts, intentionally or unintentionally, as a demodulator .
Some organisms, such as elephants, [15] can register frequencies between 0 and 20 Hz (infrasound), and others, such as bats, can recognize frequencies above 20,000 Hz (ultrasound) to echolocate. [14] [16] Researchers use different weights to account for noise frequency with intensity, as humans do not perceive sound at the same loudness level. [12]
Electronic pest control is the name given to any of several types of electrically powered devices designed to repel or eliminate pests, usually rodents or insects. Since these devices are not regulated under the Federal Insecticide, Fungicide, and Rodenticide Act in the United States, the EPA does not require the same kind of efficacy testing that it does for chemical pesticides.
Hearing range describes the frequency range that can be heard by humans or other animals, though it can also refer to the range of levels. The human range is commonly given as 20 to 20,000 Hz, although there is considerable variation between individuals, especially at high frequencies, and a gradual loss of sensitivity to higher frequencies ...