• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 1997년도 추계학술대회논문집; 한국과학기술회관; 6 Nov. 1997
• /
• pp.222-226
• /
• 1997

The reproducibility of measured level is a prior condition for the reliable assessment of the sound insulation performance. To review the reproducibility of impact sound level, 20 floors were selected in highrise apartment house, and then impact sound levels of two kinds of typical floors were measured with 10 times in each receiving point. The impact sound insulation class values were derived with a standard tapping machine and bang machine. Inspection of the result showed that smaller scale of the room caused to lower the reproducibility and that the higher values of standard deviation in lower frequency caused to deteriorate the reliability of assesment. Thus to enhance the reproducibility of the impact sound insulation class, greater allowable deviation of measured level is required in lower frequency than in higher one.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2002년도 춘계학술대회논문집
• /
• pp.719-723
• /
• 2002

The purpose of this study is to suggest the correlation of single-number ratings for sound insulation by floor impact. As a assessment method of impact sound insulation. we selected the IIC contour of ISO, A weighted sound level. Inverse A-weighting curve and L-Index of japanese industrial standard. And we estimated the single-number ratings by application the measured data of impact sound level to each method. The results showed that the coefficients of determination between each two single-number ratings were very high (more than 0.9169). And In the condition of same assessment method, the coefficient of determination for light-weight impact sound was higher than that for heavy-weight impact sound.

• 한국음향학회지
• /
• 제9권4호
• /
• pp.5-17
• /
• 1990

국내 설정에 적합한 차음성능기준 및 등급화 방안을 설정하기 위하여 그 기초 연구단계로서 주민반응조사 및 차음성능수준을 측정하고, 차음성능 평가치와 생활감과의 상관관계를 분석 외국의 기존 평가기준곡선 적응가능성을 검토하였다. 분석결과 ISO에 의한 평가방법보다는 JIS에 의한 평가방법이 국내 공동주택의 경우에는 보다 합리적임을 파악하였고, 표준충격원은 경량 및 중량충격원을 사용하는 것이 타당하다고 판단된다. 또한 측정시 문제가 되는 63Hz 중심 주파수대역을 측정범위에서 제외하여도 차음성능 지수상의 오차는 무시할 수 있었다.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2002년도 추계학술대회논문집
• /
• pp.486-491
• /
• 2002

Auditory experiments based on subjective responses were undertaken for the standard heavy and light weight impact noise. Relations between noise levels and subjective evaluations were also investigated. As a result, it was shown that the noise class was rated with the range of sensible satisfaction by investigating the various social responses for the floor impact noise. The rate classification for the heavy weight impact noise is suggested as a design guide for concrete slabs which satisfy the residents' requirements in various sound insulation capacities of multistory residential buildings.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2004년도 추계학술대회논문집
• /
• pp.93-96
• /
• 2004

In the case of the front door of the apartment, which functions as an entrance, the study about noise has been less active than corridor type plane in the past, since stair room type plane was generalized. Hence, this study shows the survey about residents' thoughts of noise transmission through the front door, and after researching sound insulation of the present apartments, we figured out what the problem is. Moreover, we did an efficiency test as developing the front door, which increases sound insulation. As a result, it turned out that residents think that the noise transmission through the front door is as serious as floor impact noise, and also, the efficiency of the front door is as poor as STC 22-30. Therefore, in the developed front door, we should improve the efficiency to the level of STCSS. It will be a good way preparing for a demand of residents.

• Journal of Biosystems Engineering
• /
• 제40권3호
• /
• pp.159-164
• /
• 2015

Purpose: Recently, environmental pollution and safety problems in agricultural production have become important issues. Initially, bio-production machines focused on high production efficiency rather than workers' safety and comfort, but this trend slowly has changed as time went on. Methods: This study was carried out to identify sound efficiently and reliably for noise reduction by using a combine cabin model. Ethylene propylene diene monomer (M-class) rubber (EPDM) was applied to improve noise reduction performance from parts connected directly to the front, rear, left side, and bottom side of the cabin. Results: As a result, an average noise reduction of 1.85 dB was achieved in the normal hearing range between 500 Hz to 2 kHz. Conclusions: Reducing the cabin noise levels can reduce a worker's fatigue, improve working environment, and contribute to future low-noise and high-quality cabin environment.

• 한국화재소방학회논문지
• /
• 제31권3호
• /
• pp.63-72
• /
• 2017

본 논문에서는 저압용 10회로 분전반을 전기공업협동조합(KEMC) 2102-610 규정에 근거하여 제작하였다. 또한, 개발된 10회로 분전반의 특성 평가를 실시하여 안전성을 확보하고자 한다. 개발된 10회로 분전반은 내식성, 절연 재료의 특성, 자외선 복사의 내성, 기계적 충격 등에 적합하도록 설계되었다. 개발된 분전반은 외함의 보호 등급, 감전방지와 보호회로, 개폐 장치와 구성품, 내부 전기 회로와 연결부, 외부 도체의 단자, 절연 특성, 온도 상승 시험, 열저항 등이 적합하도록 제작하였다. 개발된 10회로 분전반은 단상 회로와 3상 회로 등으로 구분되어 있다. 분기된 각각의 차단기 부하측에 센서 모듈을 설치하여 부하의 전선로에서 발생되는 누설전류의 크기를 실시간 측정할 수 있다. 그리고 부하의 용도 및 목적 등에 따라 회로를 증설할 수 있고, 각각의 부하 상태 역시 실시간 부하 관리 및 점검이 가능하다. 개발된 10회로 분전반의 온도 상승 시험을 실시한 곳은 인입 접속부, 주회로 및 분기회로 모선, 모선지지물 등 18 개소이다. 온도가 가장 높게 측정된 곳은 분기회로 모선용 MCCB 전원측 접속부의 R-phase으로 $65.3^{\circ}C$, 부하측은 T-phase으로 $61.6^{\circ}C$로 기록되었다. 그리고 내열 실험 장치를 이용하여 MCCB를 $180^{\circ}C$에서 6시간 동안 열적 스트레스를 인가하였을 때 작동 손잡이의 변형이 확인되었고, 트립 상태로 이동한 것이 확인되었다.