• Title/Summary/Keyword: measurement Noise

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Application of Sound Intensity Camera for the Noise Source Analysis (소음원 규명을 위한 음향 인텐시티 카메라 응용)

  • Lee, Chang-Myung;Bae, Young-Wook
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2009.10a
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    • pp.229-230
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    • 2009
  • A method is suggested for the noise source identification using the sound intensity method. The suggested method does not need to install the grid using wire or thread during the sound intensity measurement for the noise source identification. It utilizes a camera to show the grid on the screen not installing the real grid for the sound intensity method.

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Psophometeric Noise Voltage of Telecommunication Lines and Test methods (통신회선의 잡음전압 기준 및 측정법)

  • Hwang, Jong-Sun;Kim, Yeong-Min;Lee, Kyoung-Wook;Kim, Jae-Joon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11b
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    • pp.617-620
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    • 2001
  • The protection of communication lines against harmful effects from electricity lines is very important with the rapid development of communications network. This paper is introduced the reference of noise voltage and the test methods of foreign countries. Further we will also present study measurement equipment for telecommunications noise voltage and circuit noise phenomenon.

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Psophometeric Noise Voltage of Telecommunication Lines and Test methods (통신회선의 잡음전압 기준 및 측정법)

  • 황종선;김영민;이경욱;김재준
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11a
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    • pp.617-620
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    • 2001
  • The protection of communication lines against harmful effects from electricity lines is very important with the rapid development of communications network. This paper is introduced the reference of noise voltage and the test methods of foreign coutnreis. Further we will also present study measurement equipment for telecommunications noise voltage and circuit noise phenomenon.

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Welding Residual Stress Measurement by Barkhausen Noise Method (Barkhausen noise를 이용한 용접 잔류응력 측정)

  • Lee, S.S.;Ahn, B.Y.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.10 no.1
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    • pp.91-95
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    • 1990
  • Welding residual stress was measured by Barkhausen noise method. The calibration experiment was done for the quantitative analysis. The specimen for the calibration experiment must has the same thermo-mechanical history as the actual material to be tested. The Barkhausen noise were analysed by the pulse-height distribution. The results show that the distribution and magnitude of welding residual stress from Barkhausen noise method are in good agreement with those from blind hole method.

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Measurement and Control of Abnormal Sound for Refrigerator (냉장고의 이상소음에 관한 사례연구)

  • 주재만;김중래;이동현
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.05a
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    • pp.380-384
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    • 2001
  • The household reftigerator's noise which is closely related with resident environment can hardly be evaluated its sound quality using the Korean Standards. Radiation characteristics of compressor noise consist of tonal noise in low frequency range and, or narrow band noise in high frequency range. In this study, measuring method for detecting the abnormal and low-level noise in high frequency band is presented, and control method for its reduction is proposed. After installing wall which is similar to living condition, we determined a major concerning frequency band of noise. It can be found the directivity of high frequency noise radiated from compressor by using experiment and analysis. According to isolation of noise transfer path, remarkable noise reduction is achieved.

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A Study on a Method to Apply to Domestic Railway Vehicles in Prediction of Railway Noise Using a Noise Map (소음지도를 이용한 철도소음 예측 시 국내 철도차량 적용 방안 연구)

  • Park, Chan-Youn;Park, In-Sun;Oh, Jong-Hwa;Park, Sang-Kyu
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2008.04a
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    • pp.882-888
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    • 2008
  • The increase in logistics and the emergence of high speed vehicles are aggravating the noise problem, and disturbing large numbers of people. Therefore, growing attention is being paid to the creation and utilization of a noise map in order to grasp and predict the influence of noise, and to establish a policy that effectively reduces noise. However, so far there has been little progress in developing a predictive formula for railway noise, and a noise prediction program suitable for the domestic environment. Therefore, there is a need for a method to apply the overseas prediction formula to domestic railway vehicles. This study evaluated the prediction method, the result of which is similar to that of a real measurement, using a noise map. It also employed a commercial software program, SoundPlan, to predict noise.

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A Study on Development and Application of Noise Estimation System for Floor Noise in Apartment Buildings (공동주택 층간소음의 소음 발생 위치 추정 시스템 개발 및 적용에 관한 연구)

  • Yun, Gee-Hyei;Kim, Sang-Yong
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2019.11a
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    • pp.203-204
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    • 2019
  • Recently, the number of conflicts and complaints related to noise between floors is increasing every year. It is essential to acquisition objective noise data in order to resolve legal disputes over floor noise. However, specialized equipment for noise acquisition is difficult for ordinary apartment dwellers to use. In addition, in order to solve the problem of inter-layer noise, it is most effective to locate and remove the noise. Therefore, this study proposes a floor noise monitoring system for the measurement of floor noise and estimation of the noise source that can be measured without a professional device.

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Interval estimate of physiological fluctuation of peak latency of ERP waveform based on a limited number of single sweep records

  • Nishida, Shigeto;Nakamura, Masatoshi;Suwazono, Shugo;Honda, Manabu;Nagamine, Takashi;Shibasaki, Hiroshi
    • 제어로봇시스템학회:학술대회논문집
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    • 1994.10a
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    • pp.1.1-5
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    • 1994
  • In the single sweep record of event-related potential (ERP), the peak latency of P300, which is one of the most prominent positive peaks in the ERP record, might fluctuate according to the recording conditions. The fluctuation of the peak latency (measurement fluctuation) is the summation of the fluctuation caused by physiological factor (physiological fluctuation) and one by noise of background EEG (noise fluctuation). We propsed a method for estimating the interval of the physiological fluctuation based on a limited number of single sweep records. The noise fluctuation was estimated by using the relationship between the signal-to-noise (SN) ratio and the noise fluctuation based on the P300 model and the background EEG model. The interval estimate of the physiological fluctuation were obtained by subtracting the interval estimate of the noise fluctuation from that of the measurement fluctuation. The proposed method was tested by using simulation data of ERP and applied to actual ERP and data of normal subjects, and gave satisfactory results.

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