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Kim, Kab Bae;Jang, Jae-Kil
- Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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- 2013.04a
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- pp.739-744
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- 2013
The aim of this study is to evaluate the noise level from the machines used for tunnel construction and to analyze the noise exposure level of workers engaged in tunneling works. The sound level meter and noise dosimeters was used for the monitoring of noise in the tunneling work sites. The average noise from jumbo drill was 113.0 dE(A), the noise from pay loader was 92.4 dB(A), the noise from backhoe was 99.9 dB(A) and the noise from shotcrete machine was 94.3 dE(A). The tunneling workers were exposed to 66.9~94.9 dB(A) of noise and other workers exposed to less than 90 dB(A) of noise. Jumbo drill operators were exposed to to 82.5~84.2 dB(A) of noise, backhoe operators were exposed to 70.2~94.9 dB(A) of noise, shotcrete machine operators were exposed to 68.2~74.7 dB(A) of noise and pay loader operators were exposed to 59.2~81.3 dE(A) of noise.
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Maslov, Viatcheslav L.;Soloveitchik, Leonid I.
- Proceedings of the Acoustical Society of Korea Conference
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- 1994.06a
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- pp.860-863
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- 1994
Main sources of increased vibrations and air noise on ship are main and auxiliary engines and ship ducts. The various ways of transfer of vibration energy and air noise in passenger cabin of a vessel require, in general case, of various methods of attenuation. The transfer of vibration energy from engines through a support requires, alongside with shock-absorbers, availability active shock-absorbers. The transfer of vibration energy and hydrodynamic noise on ship ducts requires availability, alongside with flexible muffler, active mufflers. The availability of air noise from working equipment can require, along with absorbent covers, of space systems of active noise control. In the given article it is spoken about the unified approach to formation of the block-diagram of active noise and vibration control. The complex approach permits to receive additional efficiency in reduction of noise in passenger cabin of vessels.
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김재열;곽이구;송경석;안재신;이창선;윤성운
- Proceedings of the Korean Society of Precision Engineering Conference
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- 2003.06a
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- pp.942-945
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- 2003
Noise cause is dividing to fluid noise by exhaust flow of fan and vibration noise by rotational vibration of motor. Until now, measuring method has been used to measure vibration by the accelerometer, this method has been not measured for the vibration in some parts of brush and commutator because of motor construction. This research was purposed on the accurate analysis. using laser vibration analyzer, of noise cause against the difficult part in old times. By using this measured data, we would like to use for the design of silent motor.
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Jung, Young-Seok;Yoon, Sung-Won
- Journal of Korean Association for Spatial Structures
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- v.17 no.1
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- pp.93-100
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- 2017
With increasing number construction of high-rise building which has about 40 to 60 floors there have been many kinds of problem which related with usage from vibration. To predict response acceleration, it is important to assess correct natural frequency. However, due to the noise of MEMS sensor, it is difficult to measure dynamic characteristic such as natural frequency when measuring ambient vibration using MEMS sensor within cell phone. Therefore, a comparative analysis on vibration measuring applications was performed after measuring ambient vibration of 2 skyscrappers which have height between 133.5~244.3m that are located in Seoul and Observation tower using I-jishin APP with noise reduction function of MEMS sensor in order to verify the effectiveness of low noise type vibration measurement APP.
https://doi.org/10.9712/KASS.2017.17.1.093 인용 PDF KSCI