• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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• pp.598-603
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• 2002

The floor impact noise in apartment buildings has been known as the most sensitively recognized environmental noise. Therefore. inhabitants perceptual evaluation of floor impact noises was investigated by a questionnaire survey. It was found that the respondents perceive the floor impact noises from the upper nor as a constant noise level. However, if there is any child on the upper floor. the respondents felt Its noise as a harshly grating level. It was also found that the larger the respondents house is. the higher their wanted level of noise isolation is. Moreover, it was revealed that the main source of the floor impact noise from the upper floor is a child at the age from six to seven. The results could be used as fundamental data for the research on impact sources and new regulations that fit to Korean perceptual aspects and characteristics.

• 한국소음진동공학회논문집
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• 제16권8호
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• pp.789-796
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• 2006

The characteristics of the four standard floor impact sources (impact ball, bang machine, tapping machine, modified tapping machine) and a human impact source (jumping children) were investigated. First, the mechanical impedance of each source were evaluated. Then, the impact force exposure level of each source were measured. The results showed that fundamental frequency and impedance produced by the impact ball are the most similar to those of the human impact source. The frequency characteristics of the impact ball were most similar to those of jumping children. Consequently, the impact ball more accurately reproduces human impact compared to the other standard impact sources. Therefore, the impact ball should be considered as the reliable impactor in evaluating floor impact noise.

• 한국소음진동공학회논문집
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• 제24권6호
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• pp.483-492
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• 2014

Uncomfortable feelings of occupants by indoor floor impact noise in a residential building are not accurately represented by the floor impact noise from a standard impact source. It is due to the characteristics of standard impact sources, which are different from the impact forces produced by occupants. It varies significantly by impact source, and it is not easy to be replicated for testing. As a result, the indoor floor impact noise under different acoustic conditions cannot be directly compared. Using frequency response function(FRF), which represents the input-output relationships of a dynamic system, it is possible to examine the characteristics of the system. Especially, FRF can predict the response of a linear dynamic system subjected to various excitation. To determine the relationship between impact force and the corresponding response of dynamic system in residential building, the acceleration response of a concrete slab and the floor impact noise in the living room, produced by bang-machine and rubber-ball excitation, were measured. The test results are compared to the estimates based on FRF and impact force spectrum.

• 한국소음진동공학회논문집
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• 제14권8호
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• pp.661-667
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• 2004

The characteristics of noise and vibration by a heavy impact source was studied. The triggering method was used for increasing the reliability and stability to measure the level of sound pressure. sound intensity and vibration acceleration. A simple finite element model and a rigid body analysis method were suggested to calculate the natural frequencies of the multi-layer floor system. The results show that the resilient materials decrease the natural frequency of the reinforced concrete slab, make a resonance with dominant driving frequency in the low frequency region, and increase the vibration and noise level. A simple finite element model and rigid body models was suggested to calculate the natural frequencies of the floor systems.

• 한국음향학회지
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• 제42권6호
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• pp.584-593
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• 2023

본 연구는 실제 생활시 주거 건물에서 발생하는 바닥충격음과 유사한 반복적인 충격원을 개발하려 시도하고, 이렇게 개발되는 새로운 충격원에 대응하는 평가 방법을 찾기 위해 수행되었다. 새로운 충격원을 개발해야 하는 필요성은 실제 주거 건물에서의 바닥충격음과 관련된 문제가 주로 어린이의 뛰는 소리에서 비롯되기 때문이다. 그러나 바닥충격음을 측정하고 평가하는 데 사용된 표준 충격원은 단일 충격 형태로, 실제 생활에서 문제가 되는 충격원과는 다른 특성을 가진다. 연구를 위해 18개의 평가 항목을 도출하였으며, 항목에 대한 설문조사 및 청취실험을 통해 바닥충격음을 평가하는 데 적용 가능한 항목으로 심리적 영향(신경쓰임, 화가 남), 일상 생활 방해(수면 방해, 휴식 방해) 및 생리적 영향(혈압 상승) 항목을 제시하였다. 이들 항목은 개별적으로 활용될 수 있으며, 바닥충격음 평가의 유형에 따라 선택적으로 활용할 수도 있다. 이를 통해 실험실에서 청취 실험의 포괄적인 평가나 바닥충격음과 관련된 주거 환경에서의 소음 평가를 더 체계적으로 수행할 수 있을 것이다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.804-807
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• 2005

The characteristics of the standard floor impact sources and the human impact source were investigated. First, the mechanical impedance of the each source was evaluated. Second, the impact force exposure levels and impact sounds level driven by the each source were measured. The results showed that the mechanical impedance and impact force exposure level of the impact ball are the most similar to those of the human impact source among the standard impact sources.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.172-176
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• 2000

A series of preliminary experiments were carried out to quantify the annoyance are noisiness caused by floor impact noise. From the results of the experiments. the heavy impact source was found to be felt louder and noisier than the light impact source. Measurements of noise were also conducted by a diagnostic system based on the model(the model consists of the autocorrelators and the cross-correlation for signals arriving at two ear entrants) of the human auditory-brain system. Physical factors in the model were calculated by use of the ACF(autocorrelation function) and IACF(interaural cross correlation function) of binaural signals. From the ACF/IACF analysis, it was found that perceived loudness of floor impact noise could be represented by the factors of the ACF/IACF model.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 추계학술대회논문집
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• pp.441-446
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• 2008

The source transfer receiver model ('Source $\times$ Transfer = Response' model) which is widely used by NVH development process of vehicle/transport/machinery to analyze effectively and manage efficiently the structural dynamic behavior is also applicable to construction structure. If the evaluation assessment of the vibration level does not meet the target level, there are two methods, one is source treatment or replacement and the other is the reduction treatment on the transfer structure. In case of source treatment, it is done by source supplier and so, the latter is more practical method to reduce the vibration level. In this study, in order to get the accurate Transfer FE model(floor structure FE model), Experimental modal analysis of part of floor structure and FEM modal analysis of full floor structure are performed, then updating of FE model is performed after correlation analysis between these two results and finally, the modal model and FRF are compared between FE and Experimental results.

• 소음진동
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• 제2권1호
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• pp.21-31
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• 1992

In the previous paper, we report a practical floor impact sound level prediction method for a heavyweight impact source(Tire), soft impact source such as children jumping and running. According to these results, the calculated value and the measured value correspond comparatively well, regardless of differences in the floor structures. And the floor impact sound for a heavyweight impact source, soft source was strongly influenced by structural factors such as floor slab stiffness and peripheral support conditions. But the floor impact sound for a light impact source (Tapping machine), hard impact source was influenced by resilient layers, composed of multi-layer in floor structures. Thus, In this paper, 4 actual floor structures, all with differing resilient layers, were calculated using impedance method. When these calculation values were compared with the measured values, approximately all the values fell with one rank of the sound insulation grade, reference curve(L curve) by the JIS standard. So, a sample of measured values and calculated values from floor structures is presented to show the accuracy and appropriateness of the impedance method in domestic.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.371-371
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• 2006

The purpose of this study is to provide a fundamental data for efficient and economical reduction method and predict ion method of floor impact noise. In order to get the useful results, the measurement on the vibration transmission characteristics of standard test building with four rooms by using heavy and light-weighed impact source were carried out. In this measurement various conditions such as the change of test structure construction, the pick-up sensor location, the excitation posit ion, and the resilient material types were applied to get the vibration characteristics transmitted from excitation room to adjacent rooms.