• 한국음향학회지
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• 제30권1호
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• pp.17-21
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• 2011

수중에서 음향신호를 측정할 때에 청음기 주위에서의 유동에 의해 발생하는 초저주파 대역 자체소음을 저감시키기 위해 청음기 주위에 다공성 발포재를 씌우는 기법의 효과를 해상 실험을 통해 고찰하였다. 두께가 다른 10 ppi 폴리우레탄 발포재를 이용하여 실험한 결과, 2-10 Hz 대역에서 발포재의 두께가 1 cm일 때에는 최대 20 dB 그리고 발포재의 두께가 3 cm인 경우에는 최대 28 dB의 자체소음 저감 효과가 있음을 확인하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1989년도 춘계학술대회 논문집
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• pp.114-117
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• 1989

An infrasonic wide band transducer fabricated by polytetrafluoroethylene(PTFE)is studied experimentally. The sensitivity of the transducer depends largely on the surface charge of the Electret and is typically between-50 and -62[dBV] for a sound-pressure level of 1[ubar]. The sensitivity of the transducer does not decay over periods of the order of years at room temperature. The frequency response is within 1.5[dB] from 1 to 6,000[Hz] and within 12[dB] from 0.05[Hz] to 1[Hz] respectively. The resonance frequency of the element is 510 [Hz]. We conjectures that the element is applicable to accustics, communication system, seismological observation and other similar filed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 하계종합학술대회 논문집
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• pp.367-369
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• 1989

An infrasonic wide band transducer fabricated by polyvinylidenefluoride[PVDF] is studied experimentally. The sensitivity of transducer is fixed -53[dB] at frequency range from $10^{-2}$[Hz] to 2[Hz] and fixed -42[dB] range from 10[Hz] to 400[Hz] respectively. The resonance frequency of the element is 14[Hz], which is accord with the mechanical resonance frequency 25.5 [Hz]. We conjecture that the element is applicable to acoustics, communication system,seismological observation and other similiar fields.