• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.13 no.1
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• pp.3-9
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• 2003

In an apartment building, the impact sound from upstairs has been regarded as a main source of noise causing discontentment among occupants. To set the optimum design for sound insulation. it is nesessary to suggest the useful tools or technique that predict the floor impact sound. The purpose of this study is to investigate the applicability of the theory of sound radiation. We measured the vibration acceleration levels on the interior structures and predicted the sound pressure level of the room by using them. The result show that the predicted value, in general, were in good agreement with the measured values within 5∼10% in error rate.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.255-260
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• 2003

The regulation for floor impact sound level is expected to be amended to 50㏈(L$\_$i, Fmax, AW/) and below in heavy-weight impact sound and 58㏈(L'$\_$n, AW/) and below in light-weight impact sound in Korea. The purpose of this paper is to analyze the influence factors of floor impact sound levels in apartments. The influence factors were air pressure of bang machine, height of microphones, data acquisition rate, etc. The air pressure range of bang machine were from 2.2 Pa to 2.6 Fa. Five microphones were installed at a height of 0.5m, 0.7m, 0.9m, 1.2m, 1.5m or 1.7m from floor level. The floor impact sound level was varied about 1-3㏈(L$\_$i, Fmax, AW/) in heavy-weight impact sound according to the influence factors.

• The Journal of the Acoustical Society of Korea
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• v.40 no.6
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• pp.607-614
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• 2021

Research on elevator noise has mainly focused on the cause of its occurrence and measures to reduce it. There is still insufficient research on how to accurately measure and evaluate elevator noise. There is a measurement method established as an international standard for the measurement method, but it is also difficult to apply to high-rise apartments, and there are many cases that do not closely reflect the characteristics of elevator noise. In order to solve this problem, a study was conducted to improve the elevator noise measurement method in the current standard. In this study, the characteristics of elevator noise were closely identified. Through frequency analysis of the elevator noise and other equipment, it was verified that the elevator noise is noise with different characteristics from other equipment. Elevator noise was compared with heavy floor impact noise, which is a representative structural transmission noise, as structural transmission noise. Elevator noise was compared with heavy floor impact noise, which is a representative structural transmission noise, as structural transmission noise. The correlation between bang machine and rubber ball was found to be very high at 0.9 level. As a result, it was verified that the mid-low frequency band of the elevator noise is the main structural transmission noise and cannot be evaluated together with other equipment.

• Explosives and Blasting
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• v.25 no.1
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• pp.1-14
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• 2007

A blasting noise generated by blasting work, which is a kind of shock-noise, influences the human body. A civil appeal due to blasting noise causes work discontinuance and downsizing of a blasting scale. Most of soundproof facilities for reducing a blasting noise is installed at each working spot by itself and the degree of a noise reduction is very low. The aim of this study is to recommend a technology on noise reduction considering the method and material of soundproof facilities. As the first study step to acquire basic data, investigations on the installation time, installation method, and material of the soundproof facilities have been done at about 20 tunnel work spots such as railroad tunnel, road tunnel, tunnel for electric power.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1992.10a
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• pp.147-152
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• 1992

본 연구에서는 같은 직경의 2개 원형구멍이 동축상에 있는 4변고정, 등반성 정사각형판의 자유진동특성을 충격진동실험과 유한요소 해서방법으로 원형 구멍직경의 변화에 다른 고유진동수와 무차원 진동수 매개변수를 구하고자 한다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.04a
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• pp.415-416
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• 2011

• Journal of KSNVE
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• v.12 no.2
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• pp.103-112
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• 2002

인간이 도구를 사용한 이래 진동과 충격의 인체 피폭은 점진적으로 증가되었으며, 산업 혁명의 부산물인 동력기관을 이용하는 육-해-공 운송수단의 20세기 발전은 인체진동 피폭의 급격한 증대를 수반하였다. 자동차를 포함한 운송수단은 21세기 우리생활의 필수품으로 확고한 자리를 잡을 것이 확실시된다. 우리 주변의 수많은 진동 발생원들과 이에 직간접적으로 노출되어있는 현대인의 생활은 진동에 대한 새로운 이해와 접근방법의 개척을 요구하여 새로운 공학분야를 잉태하였다.(중략)

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11b
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• pp.1353-1355
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• 2001

고도의 산업발달과 더불어 신뢰성 분야의 비중이 증대됨에 따라 진동 및 충격과 관련 시험방법 규격이 국내 및 해외 시장에서 절실히 요구되고 있는 실정이다. 우리나라는 현재 많은 한국산업표준(KS규격)을 보유하고 있으나, 국가규격인 KS규격과 ISO/IEC 등 국제규격과 차이점이 있어 제조업체의 경쟁력 약화의 요인으로 작용하고 있다. (중략)

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.626-630
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• 2006

This study investigates the effects of Interaural Cross-correlation(IACC) and its variation on annoyance of the heavy-weight impact sounds. Subjects evaluated the annoyance of the heavy-weight floor impact sounds recorded in rooms of apartments which have different sound insulation treatments; furnished and occupied conditions are characterized by the ACF/IACF factors. A paired comparison test was conducted using the impact sound sources whose IACC and variation of IACC values were different. It was found that IACC is inversely correlated with the scale value(r=-0.62) whereas the variation of IACC is not(r=-0.34). On the contrary, ${\Phi}(0)$ is highly correlated with scale value of annoyance and ${\Phi}(0)$ is need to be controlled as constant to find the effect of IACC on annoyance.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.468-473
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• 2002

The purpose of this study was to present the possible use of a new standard impactor, the rubber ball(so called, impact ball), and to assess its evaluation method as for heavy-weight impact in multi-story residential buildings, Several experiments were carried out to investigate the effect of the impact on noise propagation in reinforced concrete buildings. Then, the noise from the impact ball was psychoacoustically evaluated. The correlation between the L-value evaluation methods and auditory responses was also investigated. Results show that the ball noise is quite similar to the jumping noise. The noise level of ball is even higher than the bang machine noise, although it has much lower impact force. It was also found that L-indexing seems to bge inappropriate for evaluation of ball noise.