• Title/Summary/Keyword: Noise measures

Search Result 462, Processing Time 0.025 seconds

Characteristics of Conventional Railroad Noise (재래식 철도소음 특성)

  • Kang, Daejoon;Lee, Wooseok;Lee, Jaewon;Hong, Junki
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.15 no.5 s.98
    • /
    • pp.511-518
    • /
    • 2005
  • The railroad noise has been considered as one of environment pollution and complaints about it have been increasing every year. Therefore, the establishment of railroad noise monitoring network is necessary. It will be designed for monitoring railroad noise, storing data of railroad noise continuously and providing the fundamental knowledge for the measures of railroad noise. For this, we investigated the actual condition and status of railroad noise according to distance around Daejeon, Daegu, Gwangju, and Busan. This paper shows the basic data that will be used for predicting the noise level near railroad in the environmental impact assessment.

A Study on the Vertical SPL of Railway Noise by Noise Barrier (방음벽 설치에 따른 철도소음의 수직음압레벨 분포특성에 관한 연구)

  • 윤해동;윤희경;김재수
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2002.05a
    • /
    • pp.1099-1103
    • /
    • 2002
  • With rapidly industrial development, a railway has become of a main traffic means. But, the railway noise has caused much annoyance for the residents living nearby railway tracks. Therefore, in our country, for established of quite dwelling environment. execute regulation standard of railway noise from January 1. 2000. Efficiency soundproofing measures, however, are very difficult because of the lack of basic data and insufficiency of the existing research. In this point. this study attempts to survey the vertical sound pressure level of railway noise in by existence of noise harrier And this study intends to get the basic data for establishment of a efficient noise barrier about railway noise.

  • PDF

Noise & Vibration Evaluation and Analysis for Propeller Fan System of Air Conditioner Outdoor Unit (에어컨 실외기 프로펠러 홴계의 진동소음 평가 및 해석)

  • Park, Deug-Yong;Mo, Jin-Yong;Lee, Jin-Kyo;Koo, Hyoung-Mo;Choi, Weon-Seok
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2000.06a
    • /
    • pp.1405-1409
    • /
    • 2000
  • The electro-magnetic noise generated from fan-driving motor is one of important items in view of abnormal noise which affect the quality of air conditioner noise. The electro-magnetic noise of the outdoor unit is identified by the serial experiments for related parts, whose effects are verified to give proper measures for reduced noise level. The weight of fan appears to be the most important factor, and the stiffness of the frame, such as motor bracket is shown to be important also.

  • PDF

What are measures to reduce interior noise for KTX in tunnel with concrete track? (콘크리트 궤도 터널 주행 시 KTX차량의 실내소음 저감방안은 무엇인가?)

  • Kim J.C.;Koh H.I.;Lee C.W.
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2006.05a
    • /
    • pp.29-30
    • /
    • 2006
  • The interior noise of KTX in tunnel has become an issue since the commercial operating in April 2004. The analysis of the interior noise of KTX in tunnel with concrete track shows sharply increased noise level in the range of 80Hz that is the natural frequency of the KTX carbody. We know that the booming noise inside KTX in tunnel with concrete track is generated by noise outside gangway and rolling noise at the carbody natural frequency. In this Study noise reduction methods are discussed on the basis of the comparison of the KTX and KHST noise characteristics. Alternatively, the effect of the modified mud-flap on the interior noise is introduced.

  • PDF

Effects of the Types of Noise and Signal-to-Noise Ratios on Speech Intelligibility in Dysarthria (소음 유형과 신호대잡음비가 마비말장애인의 말명료도에 미치는 영향)

  • Lee, Young-Mee;Sim, Hyun-Sub;Sung, Jee-Eun
    • Phonetics and Speech Sciences
    • /
    • v.3 no.4
    • /
    • pp.117-124
    • /
    • 2011
  • This study investigated the effects of the types of noise and signal to noise ratios (SNRs) on speech intelligibility of an adult with dysartrhia. Speech intelligibility was judged by 48 naive listeners using a word transcription task. Repeated measures design was used with the types of noise (multi-talker babble/environmental noise) and SNRs (0, +10 dB, +20 dB) as within-subject factors. The dependent measure was the percentage of correctly transcribed words. Results revealed that two main effects were statistically significant. Listeners performed significantly worse in the multi-talker babble condition than the environmental noise condition, and they performed significantly better at higher levels of SNRs. The current results suggested that the multi-talker babble and lower level of SNRs decreased the speech intelligibility of adults with dysarthria, and speech-language pathologists should consider environmental factors such as the types of noise and SNRs in evaluating speech intelligibility of adults with dysarthria.

  • PDF

Application of Air-Borne Noise Path Analysis to a real vehicle (실차에 대한 공기기인 소음경로분석법 적응)

  • Kim, Yoon-Jae;Jeong, Won-Tae;Song, Moon-Seong;Kang, Yeon-June;Kim, Hong-Bin
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2006.11a
    • /
    • pp.699-702
    • /
    • 2006
  • Noise Path Analysis is commonly used method to analysis noise transmission characteristics of a system. To analysis transfer paths of a system, it is necessary to know operating forces at each transfer path. The method to find out operating forces is divided into two methods. The one is a direct method which measures operating forces directly and the other is an indirect method which estimates operating forces mathematically. However, the indirect method is more commonly used because of the difficulty of measurement. This paper is focused on the indirect method and air-borne noise of a vehicle. Noise Path Analysis for Air-Borne Noise is applied to a real vehicle.

  • PDF

Noise Management Process for Big Scale Concrete Pouring in Urban Area (도심지 대규모 콘크리트 타설시 소음관리 사례)

  • An, Jang-Ho;Lee, Joo-Ho;Lee, Jun-Seo;Kim, Il-Min
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2012.04a
    • /
    • pp.787-790
    • /
    • 2012
  • In downtown, construction noise related claims are the most important issues. Sometimes noise related claims halt the construction process. Therefore, Introduction of noise reduction measures is common to construction process with a loud noise. This case is about concrete pouring for mat foundation of super tall building. Concrete pouring process using High Pressure Pumping machine causes high noise level in the vicinity of area. And large number of transit-mixer truck cause traffic congestion. This paper introduces effort and process to prevention of construction noise claims on massive scale concrete pouring.

  • PDF

Railroad Noise and its Impact (철도소음과 그 영향)

  • 강대준
    • Journal of KSNVE
    • /
    • v.7 no.5
    • /
    • pp.827-836
    • /
    • 1997
  • To suggest the standard of railroad noise and its measures and grasp its status 15 open sites of the Jungang. Taeback and Youngdong line in which the background noise level is very low and the railroad is at grade and 7 urban sites of the Kyungboo and Honam line were selected and the sound level which 373 trains passing through the former and 271 trains passing through the latter emitted was investigated. The community response of railroad noise was surveyed for apartment near wayside. Noise reduction of wall for apartment at the wayside was investigated. The prediction of electric train subway noise is derived for the environment impact assessment.

  • PDF

Evaluation and countermeasure for Environmental Noise during Plant Commissioning Process in Thermal Power Plant (화력발전소 시운전시 인근에 미치는 소음영향 및 대책)

  • Kim, Yeon-Whan;Koo, Jae-Raeyang;Kim, Hee-Soo;Bae, Yong-Chae;Lee, Hyun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2001.11b
    • /
    • pp.897-902
    • /
    • 2001
  • This paper describes the evaluation of noise influence for residental and boundary areas in 75MW thermal power plant. It includes the measurements of noise level around the boundary area of the plant, identification of noise propagating path, and discussion on the measures. Noise assessments are carried out based on the ISO 3744, ISO 9613-1 and ISO 9613-2 to predict the noise distribution of specific locations from the noise sources such as power transformers, flash vent-pipe, I.D.fan, and stack. It is identified the vent-pipe of flash tank in thermal power plant as the root cause of the environmental noise during the plant commissioning process.

  • PDF