• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2013.04a
• /
• pp.766-767
• /
• 2013

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2005.11a
• /
• pp.389-389
• /
• 2005

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2006.11a
• /
• pp.631-635
• /
• 2006

In this study, simplified methods on measurement and evaluation of heavy-wight impact sound was proposed due to provide easy quality control method to construction engineers. The simplified methods include using of rubber impact ball instead of bang machine, reduced number of measuring and impact positions which is prescribed as over 4 points, using of hand-held sound level meter as a frequency analyser and prediction equation for $L_{i.Fmax.AW}$, single number rating, using $L_{Amax}$, and $L_{Lmax}$ at each frequency band. The results showed that a method of boundary driving and boundary measuring is the most similar to the current rating method.

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

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.18 no.5
• /
• pp.533-540
• /
• 2008

In this study, a new slab system where a part of precast slab is connected each other by viscoelastic material is proposed and numerical analysis is performed to evaluate the effect of the connection between the material and PC slab on the vibration and noise control. Substructuring is introduced to develop the equation of motion for the slab system. In addition, the optimal properties of viscoelastic material are investigated. For the performance evaluation of the new slab system, the sound power and acceleration responses of the slab are compared with those of two way slab and one way slab, respectively. Numerical analysis results show that the sound power of the new slab system can be reduced by viscoelastic material significantly.

• The Journal of the Acoustical Society of Korea
• /
• v.19 no.1
• /
• pp.73-77
• /
• 2000

It is necessary to express and evaluate annoyances, caused by noises, as a comparable quantity for establishing an efficient, economic and user-oriented noise control plan. In particular, cares should be taken for impact noises, since their dynamic properties are different from those of steady-state noises. A series of preliminary experiments were carried out to quantify the annoyances caused by floor impact noises. Results suggests that the characteristics of an impact source was more important factor than the properties of a floor structure for determining loudness and noisiness of subjects. Also, the heavy impact source was found to be felt louder and noisier by 5-6dB than the light impact source.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2001.05a
• /
• pp.1077-1082
• /
• 2001

기존의 타이어를 사용한 중량충격음에 대한 차음성능 평가방법의 타당성을 살펴보기 위하여 청감실험에 의한 감성적 반응결과와 L등급 및 Leq에 의한 평가 결과를 비교 분석하였다. 동일한 바닥충격원에 대한 분석결과 L등급평가 보다 Leq에 의한 평가가 청감실험의 반응에 잘 대응하는 것으로 나타났다. 또한, Zwicker parameters 중 Loudness와 Unbiased Annoyance는 청감실험과 가장 유사한 경향을 보였다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2006.05a
• /
• pp.1252-1255
• /
• 2006

The government has enforced Housing Performance Grade Indication System (Article 21, Paragraph 2 of Housing Act) starting January 2006 for the purpose of giving users in hope of toying an apartment opportunities to select housing based on personal preferences by providing information on housing performance at the time of tenant recruitment announcement as well as securing desirable environment (comfort) by encouraging construction companies to build housing of the indicated performance level. The acoustic performance indication items include three items such as floor impact isolation performance(light weight impact sound, heavy weight impact sound), bathroom noise and insulation performance of boundary walls between households. This paper explains the background, the basis of creation and evaluation method focused on the acoustic environment performance helping for the developer of technique and a staff in charge of construction business who cope with this system.

• Journal of KSNVE
• /
• v.11 no.3
• /
• pp.443-448
• /
• 2001

The subjective unwantedness felt from the noise sources in living environment has been evaluated by investigating the limit of perceptual loudness of the noise. The noise limits were selected by the subjects. And the noises were analyzed to find out whether there is any correlation with Zwicker parameters and ACF/IACF factors. It seemed that the loudness of noise from vacuum cleaner does not affect its perceives noisiness. Traffic noise also seems to be less influential in annoyance rating. It was resealed that floor impact noise generated by bang machine is the most irritating noise that can be heard in residential buildings.

• IEMEK Journal of Embedded Systems and Applications
• /
• v.17 no.1
• /
• pp.9-17
• /
• 2022

As the COVID-19 pandemic situation worsens, the time spent indoors increases, and the exposure to indoor environmental pollution such as indoor air pollution and noise also increases, causing problems such as deterioration of human health, stress, and discord between neighbors. This paper designs and implements a system that measures and monitors indoor air quality and noise, which are representative evaluation criteria of the indoor environment. The system proposed in this paper consists of a particulate matter measurement subsystem that measures and corrects the concentration of particulate matters to monitor indoor air quality, and a noise measurement subsystem that detects changes in sound and converts it to a sound pressure level. The concentration of indoor particulate matters is measured using a laser-based light scattering method, and an error caused by temperature and humidity is compensated in this paper. For indoor noise measurement, the voltage measured through a microphone is basically measured, Fourier transform is performed to classify it by frequency, and then A-weighting is performed to correct loudness equality. Then, the RMS value is obtained, high-frequency noise is removed by performing time-weighting, and then SPL is obtained. Finally, the equivalent noise level for 1 minute and 5 minutes are calculated to show the indoor noise level. In order to classify noise into direct impact sound and air transmission noise, a piezo vibration sensors is mounted to determine the presence or absence of direct impact transmitted through the wall. For performance evaluation, the error of particulate matter measurement is analyzed through TSI's AM510 instrument. and compare the noise error with CEM's noise measurement system.